Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

17 files changed, 6725 insertions, 0 deletions

diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig
new file mode 100644
index 000000000..64012cda4
--- /dev/null
+++ b/drivers/auxdisplay/Kconfig
@@ -0,0 +1,519 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# For a description of the syntax of this configuration file,
+# see Documentation/kbuild/kconfig-language.rst.
+#
+# Auxiliary display drivers configuration.
+#
+
+menuconfig AUXDISPLAY
+	bool "Auxiliary Display support"
+	help
+	  Say Y here to get to see options for auxiliary display drivers.
+	  This option alone does not add any kernel code.
+
+	  If you say N, all options in this submenu will be skipped and disabled.
+
+if AUXDISPLAY
+
+config CHARLCD
+	tristate "Character LCD core support" if COMPILE_TEST
+	help
+	  This is the base system for character-based LCD displays.
+	  It makes no sense to have this alone, you select your display driver
+	  and if it needs the charlcd core, it will select it automatically.
+	  This is some character LCD core interface that multiple drivers can
+	  use.
+
+config LINEDISP
+	tristate "Character line display core support" if COMPILE_TEST
+	help
+	  This is the core support for single-line character displays, to be
+	  selected by drivers that use it.
+
+config HD44780_COMMON
+	tristate "Common functions for HD44780 (and compatibles) LCD displays" if COMPILE_TEST
+	select CHARLCD
+	help
+	  This is a module with the common symbols for HD44780 (and compatibles)
+	  displays. This is the code that multiple other modules use. It is not
+	  useful alone. If you have some sort of HD44780 compatible display,
+	  you very likely use this. It is selected automatically by selecting
+	  your concrete display.
+
+config HD44780
+	tristate "HD44780 Character LCD support"
+	depends on GPIOLIB || COMPILE_TEST
+	select HD44780_COMMON
+	help
+	  Enable support for Character LCDs using a HD44780 controller.
+	  The LCD is accessible through the /dev/lcd char device (10, 156).
+	  This code can either be compiled as a module, or linked into the
+	  kernel and started at boot.
+	  If you don't understand what all this is about, say N.
+
+config KS0108
+	tristate "KS0108 LCD Controller"
+	depends on PARPORT_PC
+	default n
+	help
+	  If you have a LCD controlled by one or more KS0108
+	  controllers, say Y. You will need also another more specific
+	  driver for your LCD.
+
+	  Depends on Parallel Port support. If you say Y at
+	  parport, you will be able to compile this as a module (M)
+	  and built-in as well (Y).
+
+	  To compile this as a module, choose M here:
+	  the module will be called ks0108.
+
+	  If unsure, say N.
+
+config KS0108_PORT
+	hex "Parallel port where the LCD is connected"
+	depends on KS0108
+	default 0x378
+	help
+	  The address of the parallel port where the LCD is connected.
+
+	  The first  standard parallel port address is 0x378.
+	  The second standard parallel port address is 0x278.
+	  The third  standard parallel port address is 0x3BC.
+
+	  You can specify a different address if you need.
+
+	  If you don't know what I'm talking about, load the parport module,
+	  and execute "dmesg" or "cat /proc/ioports". You can see there how
+	  many parallel ports are present and which address each one has.
+
+	  Usually you only need to use 0x378.
+
+	  If you compile this as a module, you can still override this
+	  using the module parameters.
+
+config KS0108_DELAY
+	int "Delay between each control writing (microseconds)"
+	depends on KS0108
+	default "2"
+	help
+	  Amount of time the ks0108 should wait between each control write
+	  to the parallel port.
+
+	  If your LCD seems to miss random writings, increment this.
+
+	  If you don't know what I'm talking about, ignore it.
+
+	  If you compile this as a module, you can still override this
+	  value using the module parameters.
+
+config CFAG12864B
+	tristate "CFAG12864B LCD"
+	depends on X86
+	depends on FB
+	depends on KS0108
+	select FB_SYS_FILLRECT
+	select FB_SYS_COPYAREA
+	select FB_SYS_IMAGEBLIT
+	select FB_SYS_FOPS
+	default n
+	help
+	  If you have a Crystalfontz 128x64 2-color LCD, cfag12864b Series,
+	  say Y. You also need the ks0108 LCD Controller driver.
+
+	  For help about how to wire your LCD to the parallel port,
+	  check Documentation/admin-guide/auxdisplay/cfag12864b.rst
+
+	  Depends on the x86 arch and the framebuffer support.
+
+	  The LCD framebuffer driver can be attached to a console.
+	  It will work fine. However, you can't attach it to the fbdev driver
+	  of the xorg server.
+
+	  To compile this as a module, choose M here:
+	  the modules will be called cfag12864b and cfag12864bfb.
+
+	  If unsure, say N.
+
+config CFAG12864B_RATE
+	int "Refresh rate (hertz)"
+	depends on CFAG12864B
+	default "20"
+	help
+	  Refresh rate of the LCD.
+
+	  As the LCD is not memory mapped, the driver has to make the work by
+	  software. This means you should be careful setting this value higher.
+	  If your CPUs are really slow or you feel the system is slowed down,
+	  decrease the value.
+
+	  Be careful modifying this value to a very high value:
+	  You can freeze the computer, or the LCD maybe can't draw as fast as you
+	  are requesting.
+
+	  If you don't know what I'm talking about, ignore it.
+
+	  If you compile this as a module, you can still override this
+	  value using the module parameters.
+
+config IMG_ASCII_LCD
+	tristate "Imagination Technologies ASCII LCD Display"
+	depends on HAS_IOMEM
+	default y if MIPS_MALTA
+	select MFD_SYSCON
+	select LINEDISP
+	help
+	  Enable this to support the simple ASCII LCD displays found on
+	  development boards such as the MIPS Boston, MIPS Malta & MIPS SEAD3
+	  from Imagination Technologies.
+
+config HT16K33
+	tristate "Holtek Ht16K33 LED controller with keyscan"
+	depends on FB && I2C && INPUT
+	select FB_SYS_FOPS
+	select FB_SYS_FILLRECT
+	select FB_SYS_COPYAREA
+	select FB_SYS_IMAGEBLIT
+	select INPUT_MATRIXKMAP
+	select FB_BACKLIGHT
+	select NEW_LEDS
+	select LEDS_CLASS
+	select LINEDISP
+	help
+	  Say yes here to add support for Holtek HT16K33, RAM mapping 16*8
+	  LED controller driver with keyscan.
+
+config LCD2S
+	tristate "lcd2s 20x4 character display over I2C console"
+	depends on I2C
+	select CHARLCD
+	help
+	  This is a driver that lets you use the lcd2s 20x4 character display
+	  from Modtronix engineering as a console output device. The display
+	  is a simple single color character display. You have to connect it
+	  to an I2C bus.
+
+config ARM_CHARLCD
+	bool "ARM Ltd. Character LCD Driver"
+	depends on PLAT_VERSATILE
+	help
+	  This is a driver for the character LCD found on the ARM Ltd.
+	  Versatile and RealView Platform Baseboards. It doesn't do
+	  very much more than display the text "ARM Linux" on the first
+	  line and the Linux version on the second line, but that's
+	  still useful.
+
+menuconfig PARPORT_PANEL
+	tristate "Parallel port LCD/Keypad Panel support"
+	depends on PARPORT
+	select HD44780_COMMON
+	help
+	  Say Y here if you have an HD44780 or KS-0074 LCD connected to your
+	  parallel port. This driver also features 4 and 6-key keypads. The LCD
+	  is accessible through the /dev/lcd char device (10, 156), and the
+	  keypad through /dev/keypad (10, 185). This code can either be
+	  compiled as a module, or linked into the kernel and started at boot.
+	  If you don't understand what all this is about, say N.
+
+if PARPORT_PANEL
+
+config PANEL_PARPORT
+	int "Default parallel port number (0=LPT1)"
+	range 0 255
+	default "0"
+	help
+	  This is the index of the parallel port the panel is connected to. One
+	  driver instance only supports one parallel port, so if your keypad
+	  and LCD are connected to two separate ports, you have to start two
+	  modules with different arguments. Numbering starts with '0' for LPT1,
+	  and so on.
+
+config PANEL_PROFILE
+	int "Default panel profile (0-5, 0=custom)"
+	range 0 5
+	default "5"
+	help
+	  To ease configuration, the driver supports different configuration
+	  profiles for past and recent wirings. These profiles can also be
+	  used to define an approximative configuration, completed by a few
+	  other options. Here are the profiles :
+
+	    0 = custom (see further)
+	    1 = 2x16 parallel LCD, old keypad
+	    2 = 2x16 serial LCD (KS-0074), new keypad
+	    3 = 2x16 parallel LCD (Hantronix), no keypad
+	    4 = 2x16 parallel LCD (Nexcom NSA1045) with Nexcom's keypad
+	    5 = 2x40 parallel LCD (old one), with old keypad
+
+	  Custom configurations allow you to define how your display is
+	  wired to the parallel port, and how it works. This is only intended
+	  for experts.
+
+config PANEL_KEYPAD
+	depends on PANEL_PROFILE="0"
+	int "Keypad type (0=none, 1=old 6 keys, 2=new 6 keys, 3=Nexcom 4 keys)"
+	range 0 3
+	default 0
+	help
+	  This enables and configures a keypad connected to the parallel port.
+	  The keys will be read from character device 10,185. Valid values are :
+
+	    0 : do not enable this driver
+	    1 : old 6 keys keypad
+	    2 : new 6 keys keypad, as used on the server at www.ant-computing.com
+	    3 : Nexcom NSA1045's 4 keys keypad
+
+	  New profiles can be described in the driver source. The driver also
+	  supports simultaneous keys pressed when the keypad supports them.
+
+config PANEL_LCD
+	depends on PANEL_PROFILE="0"
+	int "LCD type (0=none, 1=custom, 2=old //, 3=ks0074, 4=hantronix, 5=Nexcom)"
+	range 0 5
+	default 0
+	help
+	   This enables and configures an LCD connected to the parallel port.
+	   The driver includes an interpreter for escape codes starting with
+	   '\e[L' which are specific to the LCD, and a few ANSI codes. The
+	   driver will be registered as character device 10,156, usually
+	   under the name '/dev/lcd'. There are a total of 6 supported types :
+
+	     0 : do not enable the driver
+	     1 : custom configuration and wiring (see further)
+	     2 : 2x16 & 2x40 parallel LCD (old wiring)
+	     3 : 2x16 serial LCD (KS-0074 based)
+	     4 : 2x16 parallel LCD (Hantronix wiring)
+	     5 : 2x16 parallel LCD (Nexcom wiring)
+
+	   When type '1' is specified, other options will appear to configure
+	   more precise aspects (wiring, dimensions, protocol, ...). Please note
+	   that those values changed from the 2.4 driver for better consistency.
+
+config PANEL_LCD_HEIGHT
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1"
+	int "Number of lines on the LCD (1-2)"
+	range 1 2
+	default 2
+	help
+	  This is the number of visible character lines on the LCD in custom profile.
+	  It can either be 1 or 2.
+
+config PANEL_LCD_WIDTH
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1"
+	int "Number of characters per line on the LCD (1-40)"
+	range 1 40
+	default 40
+	help
+	  This is the number of characters per line on the LCD in custom profile.
+	  Common values are 16,20,24,40.
+
+config PANEL_LCD_BWIDTH
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1"
+	int "Internal LCD line width (1-40, 40 by default)"
+	range 1 40
+	default 40
+	help
+	  Most LCDs use a standard controller which supports hardware lines of 40
+	  characters, although sometimes only 16, 20 or 24 of them are really wired
+	  to the terminal. This results in some non-visible but addressable characters,
+	  and is the case for most parallel LCDs. Other LCDs, and some serial ones,
+	  however, use the same line width internally as what is visible. The KS0074
+	  for example, uses 16 characters per line for 16 visible characters per line.
+
+	  This option lets you configure the value used by your LCD in 'custom' profile.
+	  If you don't know, put '40' here.
+
+config PANEL_LCD_HWIDTH
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1"
+	int "Hardware LCD line width (1-64, 64 by default)"
+	range 1 64
+	default 64
+	help
+	  Most LCDs use a single address bit to differentiate line 0 and line 1. Since
+	  some of them need to be able to address 40 chars with the lower bits, they
+	  often use the immediately superior power of 2, which is 64, to address the
+	  next line.
+
+	  If you don't know what your LCD uses, in doubt let 16 here for a 2x16, and
+	  64 here for a 2x40.
+
+config PANEL_LCD_CHARSET
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1"
+	int "LCD character set (0=normal, 1=KS0074)"
+	range 0 1
+	default 0
+	help
+	  Some controllers such as the KS0074 use a somewhat strange character set
+	  where many symbols are at unusual places. The driver knows how to map
+	  'standard' ASCII characters to the character sets used by these controllers.
+	  Valid values are :
+
+	     0 : normal (untranslated) character set
+	     1 : KS0074 character set
+
+	  If you don't know, use the normal one (0).
+
+config PANEL_LCD_PROTO
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1"
+	int "LCD communication mode (0=parallel 8 bits, 1=serial)"
+	range 0 1
+	default 0
+	help
+	  This driver now supports any serial or parallel LCD wired to a parallel
+	  port. But before assigning signals, the driver needs to know if it will
+	  be driving a serial LCD or a parallel one. Serial LCDs only use 2 wires
+	  (SDA/SCL), while parallel ones use 2 or 3 wires for the control signals
+	  (E, RS, sometimes RW), and 4 or 8 for the data. Use 0 here for a 8 bits
+	  parallel LCD, and 1 for a serial LCD.
+
+config PANEL_LCD_PIN_E
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1" && PANEL_LCD_PROTO="0"
+	int "Parallel port pin number & polarity connected to the LCD E signal (-17...17) "
+	range -17 17
+	default 14
+	help
+	  This describes the number of the parallel port pin to which the LCD 'E'
+	  signal has been connected. It can be :
+
+	          0 : no connection (eg: connected to ground)
+	      1..17 : directly connected to any of these pins on the DB25 plug
+	    -1..-17 : connected to the same pin through an inverter (eg: transistor).
+
+	  Default for the 'E' pin in custom profile is '14' (AUTOFEED).
+
+config PANEL_LCD_PIN_RS
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1" && PANEL_LCD_PROTO="0"
+	int "Parallel port pin number & polarity connected to the LCD RS signal (-17...17) "
+	range -17 17
+	default 17
+	help
+	  This describes the number of the parallel port pin to which the LCD 'RS'
+	  signal has been connected. It can be :
+
+	          0 : no connection (eg: connected to ground)
+	      1..17 : directly connected to any of these pins on the DB25 plug
+	    -1..-17 : connected to the same pin through an inverter (eg: transistor).
+
+	  Default for the 'RS' pin in custom profile is '17' (SELECT IN).
+
+config PANEL_LCD_PIN_RW
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1" && PANEL_LCD_PROTO="0"
+	int "Parallel port pin number & polarity connected to the LCD RW signal (-17...17) "
+	range -17 17
+	default 16
+	help
+	  This describes the number of the parallel port pin to which the LCD 'RW'
+	  signal has been connected. It can be :
+
+	          0 : no connection (eg: connected to ground)
+	      1..17 : directly connected to any of these pins on the DB25 plug
+	    -1..-17 : connected to the same pin through an inverter (eg: transistor).
+
+	  Default for the 'RW' pin in custom profile is '16' (INIT).
+
+config PANEL_LCD_PIN_SCL
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1" && PANEL_LCD_PROTO!="0"
+	int "Parallel port pin number & polarity connected to the LCD SCL signal (-17...17) "
+	range -17 17
+	default 1
+	help
+	  This describes the number of the parallel port pin to which the serial
+	  LCD 'SCL' signal has been connected. It can be :
+
+	          0 : no connection (eg: connected to ground)
+	      1..17 : directly connected to any of these pins on the DB25 plug
+	    -1..-17 : connected to the same pin through an inverter (eg: transistor).
+
+	  Default for the 'SCL' pin in custom profile is '1' (STROBE).
+
+config PANEL_LCD_PIN_SDA
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1" && PANEL_LCD_PROTO!="0"
+	int "Parallel port pin number & polarity connected to the LCD SDA signal (-17...17) "
+	range -17 17
+	default 2
+	help
+	  This describes the number of the parallel port pin to which the serial
+	  LCD 'SDA' signal has been connected. It can be :
+
+	          0 : no connection (eg: connected to ground)
+	      1..17 : directly connected to any of these pins on the DB25 plug
+	    -1..-17 : connected to the same pin through an inverter (eg: transistor).
+
+	  Default for the 'SDA' pin in custom profile is '2' (D0).
+
+config PANEL_LCD_PIN_BL
+	depends on PANEL_PROFILE="0" && PANEL_LCD="1"
+	int "Parallel port pin number & polarity connected to the LCD backlight signal (-17...17) "
+	range -17 17
+	default 0
+	help
+	  This describes the number of the parallel port pin to which the LCD 'BL' signal
+	  has been connected. It can be :
+
+	          0 : no connection (eg: connected to ground)
+	      1..17 : directly connected to any of these pins on the DB25 plug
+	    -1..-17 : connected to the same pin through an inverter (eg: transistor).
+
+	  Default for the 'BL' pin in custom profile is '0' (uncontrolled).
+
+endif # PARPORT_PANEL
+
+config PANEL_CHANGE_MESSAGE
+	bool "Change LCD initialization message ?"
+	depends on CHARLCD
+	default "n"
+	help
+	  This allows you to replace the boot message indicating the kernel version
+	  and the driver version with a custom message. This is useful on appliances
+	  where a simple 'Starting system' message can be enough to stop a customer
+	  from worrying.
+
+	  If you say 'Y' here, you'll be able to choose a message yourself. Otherwise,
+	  say 'N' and keep the default message with the version.
+
+config PANEL_BOOT_MESSAGE
+	depends on PANEL_CHANGE_MESSAGE="y"
+	string "New initialization message"
+	default ""
+	help
+	  This allows you to replace the boot message indicating the kernel version
+	  and the driver version with a custom message. This is useful on appliances
+	  where a simple 'Starting system' message can be enough to stop a customer
+	  from worrying.
+
+	  An empty message will only clear the display at driver init time. Any other
+	  printf()-formatted message is valid with newline and escape codes.
+
+choice
+	prompt "Backlight initial state"
+	default CHARLCD_BL_FLASH
+	help
+	  Select the initial backlight state on boot or module load.
+
+	  Previously, there was no option for this: the backlight flashed
+	  briefly on init. Now you can also turn it off/on.
+
+	config CHARLCD_BL_OFF
+		bool "Off"
+		help
+		  Backlight is initially turned off
+
+	config CHARLCD_BL_ON
+		bool "On"
+		help
+		  Backlight is initially turned on
+
+	config CHARLCD_BL_FLASH
+		bool "Flash"
+		help
+		  Backlight is flashed briefly on init
+
+endchoice
+
+endif # AUXDISPLAY
+
+config PANEL
+	tristate "Parallel port LCD/Keypad Panel support (OLD OPTION)"
+	depends on PARPORT
+	select AUXDISPLAY
+	select PARPORT_PANEL
diff --git a/drivers/auxdisplay/Makefile b/drivers/auxdisplay/Makefile
new file mode 100644
index 000000000..6968ed4d3
--- /dev/null
+++ b/drivers/auxdisplay/Makefile
@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the kernel auxiliary displays device drivers.
+#
+
+obj-$(CONFIG_CHARLCD)		+= charlcd.o
+obj-$(CONFIG_HD44780_COMMON)	+= hd44780_common.o
+obj-$(CONFIG_ARM_CHARLCD)	+= arm-charlcd.o
+obj-$(CONFIG_KS0108)		+= ks0108.o
+obj-$(CONFIG_CFAG12864B)	+= cfag12864b.o cfag12864bfb.o
+obj-$(CONFIG_IMG_ASCII_LCD)	+= img-ascii-lcd.o
+obj-$(CONFIG_HD44780)		+= hd44780.o
+obj-$(CONFIG_HT16K33)		+= ht16k33.o
+obj-$(CONFIG_PARPORT_PANEL)	+= panel.o
+obj-$(CONFIG_LCD2S)		+= lcd2s.o
+obj-$(CONFIG_LINEDISP)		+= line-display.o
diff --git a/drivers/auxdisplay/arm-charlcd.c b/drivers/auxdisplay/arm-charlcd.c
new file mode 100644
index 000000000..0b1c99cca
--- /dev/null
+++ b/drivers/auxdisplay/arm-charlcd.c
@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the on-board character LCD found on some ARM reference boards
+ * This is basically an Hitachi HD44780 LCD with a custom IP block to drive it
+ * https://en.wikipedia.org/wiki/HD44780_Character_LCD
+ * Currently it will just display the text "ARM Linux" and the linux version
+ *
+ * Author: Linus Walleij <triad@df.lth.se>
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <generated/utsrelease.h>
+
+#define DRIVERNAME "arm-charlcd"
+#define CHARLCD_TIMEOUT (msecs_to_jiffies(1000))
+
+/* Offsets to registers */
+#define CHAR_COM	0x00U
+#define CHAR_DAT	0x04U
+#define CHAR_RD		0x08U
+#define CHAR_RAW	0x0CU
+#define CHAR_MASK	0x10U
+#define CHAR_STAT	0x14U
+
+#define CHAR_RAW_CLEAR	0x00000000U
+#define CHAR_RAW_VALID	0x00000100U
+
+/* Hitachi HD44780 display commands */
+#define HD_CLEAR			0x01U
+#define HD_HOME				0x02U
+#define HD_ENTRYMODE			0x04U
+#define HD_ENTRYMODE_INCREMENT		0x02U
+#define HD_ENTRYMODE_SHIFT		0x01U
+#define HD_DISPCTRL			0x08U
+#define HD_DISPCTRL_ON			0x04U
+#define HD_DISPCTRL_CURSOR_ON		0x02U
+#define HD_DISPCTRL_CURSOR_BLINK	0x01U
+#define HD_CRSR_SHIFT			0x10U
+#define HD_CRSR_SHIFT_DISPLAY		0x08U
+#define HD_CRSR_SHIFT_DISPLAY_RIGHT	0x04U
+#define HD_FUNCSET			0x20U
+#define HD_FUNCSET_8BIT			0x10U
+#define HD_FUNCSET_2_LINES		0x08U
+#define HD_FUNCSET_FONT_5X10		0x04U
+#define HD_SET_CGRAM			0x40U
+#define HD_SET_DDRAM			0x80U
+#define HD_BUSY_FLAG			0x80U
+
+/**
+ * struct charlcd - Private data structure
+ * @dev: a pointer back to containing device
+ * @phybase: the offset to the controller in physical memory
+ * @physize: the size of the physical page
+ * @virtbase: the offset to the controller in virtual memory
+ * @irq: reserved interrupt number
+ * @complete: completion structure for the last LCD command
+ * @init_work: delayed work structure to initialize the display on boot
+ */
+struct charlcd {
+	struct device *dev;
+	u32 phybase;
+	u32 physize;
+	void __iomem *virtbase;
+	int irq;
+	struct completion complete;
+	struct delayed_work init_work;
+};
+
+static irqreturn_t charlcd_interrupt(int irq, void *data)
+{
+	struct charlcd *lcd = data;
+	u8 status;
+
+	status = readl(lcd->virtbase + CHAR_STAT) & 0x01;
+	/* Clear IRQ */
+	writel(CHAR_RAW_CLEAR, lcd->virtbase + CHAR_RAW);
+	if (status)
+		complete(&lcd->complete);
+	else
+		dev_info(lcd->dev, "Spurious IRQ (%02x)\n", status);
+	return IRQ_HANDLED;
+}
+
+
+static void charlcd_wait_complete_irq(struct charlcd *lcd)
+{
+	int ret;
+
+	ret = wait_for_completion_interruptible_timeout(&lcd->complete,
+							CHARLCD_TIMEOUT);
+	/* Disable IRQ after completion */
+	writel(0x00, lcd->virtbase + CHAR_MASK);
+
+	if (ret < 0) {
+		dev_err(lcd->dev,
+			"wait_for_completion_interruptible_timeout() "
+			"returned %d waiting for ready\n", ret);
+		return;
+	}
+
+	if (ret == 0) {
+		dev_err(lcd->dev, "charlcd controller timed out "
+			"waiting for ready\n");
+		return;
+	}
+}
+
+static u8 charlcd_4bit_read_char(struct charlcd *lcd)
+{
+	u8 data;
+	u32 val;
+	int i;
+
+	/* If we can, use an IRQ to wait for the data, else poll */
+	if (lcd->irq >= 0)
+		charlcd_wait_complete_irq(lcd);
+	else {
+		i = 0;
+		val = 0;
+		while (!(val & CHAR_RAW_VALID) && i < 10) {
+			udelay(100);
+			val = readl(lcd->virtbase + CHAR_RAW);
+			i++;
+		}
+
+		writel(CHAR_RAW_CLEAR, lcd->virtbase + CHAR_RAW);
+	}
+	msleep(1);
+
+	/* Read the 4 high bits of the data */
+	data = readl(lcd->virtbase + CHAR_RD) & 0xf0;
+
+	/*
+	 * The second read for the low bits does not trigger an IRQ
+	 * so in this case we have to poll for the 4 lower bits
+	 */
+	i = 0;
+	val = 0;
+	while (!(val & CHAR_RAW_VALID) && i < 10) {
+		udelay(100);
+		val = readl(lcd->virtbase + CHAR_RAW);
+		i++;
+	}
+	writel(CHAR_RAW_CLEAR, lcd->virtbase + CHAR_RAW);
+	msleep(1);
+
+	/* Read the 4 low bits of the data */
+	data |= (readl(lcd->virtbase + CHAR_RD) >> 4) & 0x0f;
+
+	return data;
+}
+
+static bool charlcd_4bit_read_bf(struct charlcd *lcd)
+{
+	if (lcd->irq >= 0) {
+		/*
+		 * If we'll use IRQs to wait for the busyflag, clear any
+		 * pending flag and enable IRQ
+		 */
+		writel(CHAR_RAW_CLEAR, lcd->virtbase + CHAR_RAW);
+		init_completion(&lcd->complete);
+		writel(0x01, lcd->virtbase + CHAR_MASK);
+	}
+	readl(lcd->virtbase + CHAR_COM);
+	return charlcd_4bit_read_char(lcd) & HD_BUSY_FLAG ? true : false;
+}
+
+static void charlcd_4bit_wait_busy(struct charlcd *lcd)
+{
+	int retries = 50;
+
+	udelay(100);
+	while (charlcd_4bit_read_bf(lcd) && retries)
+		retries--;
+	if (!retries)
+		dev_err(lcd->dev, "timeout waiting for busyflag\n");
+}
+
+static void charlcd_4bit_command(struct charlcd *lcd, u8 cmd)
+{
+	u32 cmdlo = (cmd << 4) & 0xf0;
+	u32 cmdhi = (cmd & 0xf0);
+
+	writel(cmdhi, lcd->virtbase + CHAR_COM);
+	udelay(10);
+	writel(cmdlo, lcd->virtbase + CHAR_COM);
+	charlcd_4bit_wait_busy(lcd);
+}
+
+static void charlcd_4bit_char(struct charlcd *lcd, u8 ch)
+{
+	u32 chlo = (ch << 4) & 0xf0;
+	u32 chhi = (ch & 0xf0);
+
+	writel(chhi, lcd->virtbase + CHAR_DAT);
+	udelay(10);
+	writel(chlo, lcd->virtbase + CHAR_DAT);
+	charlcd_4bit_wait_busy(lcd);
+}
+
+static void charlcd_4bit_print(struct charlcd *lcd, int line, const char *str)
+{
+	u8 offset;
+	int i;
+
+	/*
+	 * We support line 0, 1
+	 * Line 1 runs from 0x00..0x27
+	 * Line 2 runs from 0x28..0x4f
+	 */
+	if (line == 0)
+		offset = 0;
+	else if (line == 1)
+		offset = 0x28;
+	else
+		return;
+
+	/* Set offset */
+	charlcd_4bit_command(lcd, HD_SET_DDRAM | offset);
+
+	/* Send string */
+	for (i = 0; i < strlen(str) && i < 0x28; i++)
+		charlcd_4bit_char(lcd, str[i]);
+}
+
+static void charlcd_4bit_init(struct charlcd *lcd)
+{
+	/* These commands cannot be checked with the busy flag */
+	writel(HD_FUNCSET | HD_FUNCSET_8BIT, lcd->virtbase + CHAR_COM);
+	msleep(5);
+	writel(HD_FUNCSET | HD_FUNCSET_8BIT, lcd->virtbase + CHAR_COM);
+	udelay(100);
+	writel(HD_FUNCSET | HD_FUNCSET_8BIT, lcd->virtbase + CHAR_COM);
+	udelay(100);
+	/* Go to 4bit mode */
+	writel(HD_FUNCSET, lcd->virtbase + CHAR_COM);
+	udelay(100);
+	/*
+	 * 4bit mode, 2 lines, 5x8 font, after this the number of lines
+	 * and the font cannot be changed until the next initialization sequence
+	 */
+	charlcd_4bit_command(lcd, HD_FUNCSET | HD_FUNCSET_2_LINES);
+	charlcd_4bit_command(lcd, HD_DISPCTRL | HD_DISPCTRL_ON);
+	charlcd_4bit_command(lcd, HD_ENTRYMODE | HD_ENTRYMODE_INCREMENT);
+	charlcd_4bit_command(lcd, HD_CLEAR);
+	charlcd_4bit_command(lcd, HD_HOME);
+	/* Put something useful in the display */
+	charlcd_4bit_print(lcd, 0, "ARM Linux");
+	charlcd_4bit_print(lcd, 1, UTS_RELEASE);
+}
+
+static void charlcd_init_work(struct work_struct *work)
+{
+	struct charlcd *lcd =
+		container_of(work, struct charlcd, init_work.work);
+
+	charlcd_4bit_init(lcd);
+}
+
+static int __init charlcd_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct charlcd *lcd;
+	struct resource *res;
+
+	lcd = kzalloc(sizeof(struct charlcd), GFP_KERNEL);
+	if (!lcd)
+		return -ENOMEM;
+
+	lcd->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		ret = -ENOENT;
+		goto out_no_resource;
+	}
+	lcd->phybase = res->start;
+	lcd->physize = resource_size(res);
+
+	if (request_mem_region(lcd->phybase, lcd->physize,
+			       DRIVERNAME) == NULL) {
+		ret = -EBUSY;
+		goto out_no_memregion;
+	}
+
+	lcd->virtbase = ioremap(lcd->phybase, lcd->physize);
+	if (!lcd->virtbase) {
+		ret = -ENOMEM;
+		goto out_no_memregion;
+	}
+
+	lcd->irq = platform_get_irq(pdev, 0);
+	/* If no IRQ is supplied, we'll survive without it */
+	if (lcd->irq >= 0) {
+		if (request_irq(lcd->irq, charlcd_interrupt, 0,
+				DRIVERNAME, lcd)) {
+			ret = -EIO;
+			goto out_no_irq;
+		}
+	}
+
+	platform_set_drvdata(pdev, lcd);
+
+	/*
+	 * Initialize the display in a delayed work, because
+	 * it is VERY slow and would slow down the boot of the system.
+	 */
+	INIT_DELAYED_WORK(&lcd->init_work, charlcd_init_work);
+	schedule_delayed_work(&lcd->init_work, 0);
+
+	dev_info(&pdev->dev, "initialized ARM character LCD at %08x\n",
+		lcd->phybase);
+
+	return 0;
+
+out_no_irq:
+	iounmap(lcd->virtbase);
+out_no_memregion:
+	release_mem_region(lcd->phybase, SZ_4K);
+out_no_resource:
+	kfree(lcd);
+	return ret;
+}
+
+static int charlcd_suspend(struct device *dev)
+{
+	struct charlcd *lcd = dev_get_drvdata(dev);
+
+	/* Power the display off */
+	charlcd_4bit_command(lcd, HD_DISPCTRL);
+	return 0;
+}
+
+static int charlcd_resume(struct device *dev)
+{
+	struct charlcd *lcd = dev_get_drvdata(dev);
+
+	/* Turn the display back on */
+	charlcd_4bit_command(lcd, HD_DISPCTRL | HD_DISPCTRL_ON);
+	return 0;
+}
+
+static const struct dev_pm_ops charlcd_pm_ops = {
+	.suspend = charlcd_suspend,
+	.resume = charlcd_resume,
+};
+
+static const struct of_device_id charlcd_match[] = {
+	{ .compatible = "arm,versatile-lcd", },
+	{}
+};
+
+static struct platform_driver charlcd_driver = {
+	.driver = {
+		.name = DRIVERNAME,
+		.pm = &charlcd_pm_ops,
+		.suppress_bind_attrs = true,
+		.of_match_table = of_match_ptr(charlcd_match),
+	},
+};
+builtin_platform_driver_probe(charlcd_driver, charlcd_probe);
diff --git a/drivers/auxdisplay/cfag12864b.c b/drivers/auxdisplay/cfag12864b.c
new file mode 100644
index 000000000..6526aa51f
--- /dev/null
+++ b/drivers/auxdisplay/cfag12864b.c
@@ -0,0 +1,380 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *    Filename: cfag12864b.c
+ *     Version: 0.1.0
+ * Description: cfag12864b LCD driver
+ *     Depends: ks0108
+ *
+ *      Author: Copyright (C) Miguel Ojeda <ojeda@kernel.org>
+ *        Date: 2006-10-31
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/cdev.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/workqueue.h>
+#include <linux/ks0108.h>
+#include <linux/cfag12864b.h>
+
+
+#define CFAG12864B_NAME "cfag12864b"
+
+/*
+ * Module Parameters
+ */
+
+static unsigned int cfag12864b_rate = CONFIG_CFAG12864B_RATE;
+module_param(cfag12864b_rate, uint, 0444);
+MODULE_PARM_DESC(cfag12864b_rate,
+	"Refresh rate (hertz)");
+
+unsigned int cfag12864b_getrate(void)
+{
+	return cfag12864b_rate;
+}
+
+/*
+ * cfag12864b Commands
+ *
+ *	E = Enable signal
+ *		Every time E switch from low to high,
+ *		cfag12864b/ks0108 reads the command/data.
+ *
+ *	CS1 = First ks0108controller.
+ *		If high, the first ks0108 controller receives commands/data.
+ *
+ *	CS2 = Second ks0108 controller
+ *		If high, the second ks0108 controller receives commands/data.
+ *
+ *	DI = Data/Instruction
+ *		If low, cfag12864b will expect commands.
+ *		If high, cfag12864b will expect data.
+ *
+ */
+
+#define bit(n) (((unsigned char)1)<<(n))
+
+#define CFAG12864B_BIT_E	(0)
+#define CFAG12864B_BIT_CS1	(2)
+#define CFAG12864B_BIT_CS2	(1)
+#define CFAG12864B_BIT_DI	(3)
+
+static unsigned char cfag12864b_state;
+
+static void cfag12864b_set(void)
+{
+	ks0108_writecontrol(cfag12864b_state);
+}
+
+static void cfag12864b_setbit(unsigned char state, unsigned char n)
+{
+	if (state)
+		cfag12864b_state |= bit(n);
+	else
+		cfag12864b_state &= ~bit(n);
+}
+
+static void cfag12864b_e(unsigned char state)
+{
+	cfag12864b_setbit(state, CFAG12864B_BIT_E);
+	cfag12864b_set();
+}
+
+static void cfag12864b_cs1(unsigned char state)
+{
+	cfag12864b_setbit(state, CFAG12864B_BIT_CS1);
+}
+
+static void cfag12864b_cs2(unsigned char state)
+{
+	cfag12864b_setbit(state, CFAG12864B_BIT_CS2);
+}
+
+static void cfag12864b_di(unsigned char state)
+{
+	cfag12864b_setbit(state, CFAG12864B_BIT_DI);
+}
+
+static void cfag12864b_setcontrollers(unsigned char first,
+	unsigned char second)
+{
+	if (first)
+		cfag12864b_cs1(0);
+	else
+		cfag12864b_cs1(1);
+
+	if (second)
+		cfag12864b_cs2(0);
+	else
+		cfag12864b_cs2(1);
+}
+
+static void cfag12864b_controller(unsigned char which)
+{
+	if (which == 0)
+		cfag12864b_setcontrollers(1, 0);
+	else if (which == 1)
+		cfag12864b_setcontrollers(0, 1);
+}
+
+static void cfag12864b_displaystate(unsigned char state)
+{
+	cfag12864b_di(0);
+	cfag12864b_e(1);
+	ks0108_displaystate(state);
+	cfag12864b_e(0);
+}
+
+static void cfag12864b_address(unsigned char address)
+{
+	cfag12864b_di(0);
+	cfag12864b_e(1);
+	ks0108_address(address);
+	cfag12864b_e(0);
+}
+
+static void cfag12864b_page(unsigned char page)
+{
+	cfag12864b_di(0);
+	cfag12864b_e(1);
+	ks0108_page(page);
+	cfag12864b_e(0);
+}
+
+static void cfag12864b_startline(unsigned char startline)
+{
+	cfag12864b_di(0);
+	cfag12864b_e(1);
+	ks0108_startline(startline);
+	cfag12864b_e(0);
+}
+
+static void cfag12864b_writebyte(unsigned char byte)
+{
+	cfag12864b_di(1);
+	cfag12864b_e(1);
+	ks0108_writedata(byte);
+	cfag12864b_e(0);
+}
+
+static void cfag12864b_nop(void)
+{
+	cfag12864b_startline(0);
+}
+
+/*
+ * cfag12864b Internal Commands
+ */
+
+static void cfag12864b_on(void)
+{
+	cfag12864b_setcontrollers(1, 1);
+	cfag12864b_displaystate(1);
+}
+
+static void cfag12864b_off(void)
+{
+	cfag12864b_setcontrollers(1, 1);
+	cfag12864b_displaystate(0);
+}
+
+static void cfag12864b_clear(void)
+{
+	unsigned char i, j;
+
+	cfag12864b_setcontrollers(1, 1);
+	for (i = 0; i < CFAG12864B_PAGES; i++) {
+		cfag12864b_page(i);
+		cfag12864b_address(0);
+		for (j = 0; j < CFAG12864B_ADDRESSES; j++)
+			cfag12864b_writebyte(0);
+	}
+}
+
+/*
+ * Update work
+ */
+
+unsigned char *cfag12864b_buffer;
+static unsigned char *cfag12864b_cache;
+static DEFINE_MUTEX(cfag12864b_mutex);
+static unsigned char cfag12864b_updating;
+static void cfag12864b_update(struct work_struct *delayed_work);
+static struct workqueue_struct *cfag12864b_workqueue;
+static DECLARE_DELAYED_WORK(cfag12864b_work, cfag12864b_update);
+
+static void cfag12864b_queue(void)
+{
+	queue_delayed_work(cfag12864b_workqueue, &cfag12864b_work,
+		HZ / cfag12864b_rate);
+}
+
+unsigned char cfag12864b_enable(void)
+{
+	unsigned char ret;
+
+	mutex_lock(&cfag12864b_mutex);
+
+	if (!cfag12864b_updating) {
+		cfag12864b_updating = 1;
+		cfag12864b_queue();
+		ret = 0;
+	} else
+		ret = 1;
+
+	mutex_unlock(&cfag12864b_mutex);
+
+	return ret;
+}
+
+void cfag12864b_disable(void)
+{
+	mutex_lock(&cfag12864b_mutex);
+
+	if (cfag12864b_updating) {
+		cfag12864b_updating = 0;
+		cancel_delayed_work(&cfag12864b_work);
+		flush_workqueue(cfag12864b_workqueue);
+	}
+
+	mutex_unlock(&cfag12864b_mutex);
+}
+
+unsigned char cfag12864b_isenabled(void)
+{
+	return cfag12864b_updating;
+}
+
+static void cfag12864b_update(struct work_struct *work)
+{
+	unsigned char c;
+	unsigned short i, j, k, b;
+
+	if (memcmp(cfag12864b_cache, cfag12864b_buffer, CFAG12864B_SIZE)) {
+		for (i = 0; i < CFAG12864B_CONTROLLERS; i++) {
+			cfag12864b_controller(i);
+			cfag12864b_nop();
+			for (j = 0; j < CFAG12864B_PAGES; j++) {
+				cfag12864b_page(j);
+				cfag12864b_nop();
+				cfag12864b_address(0);
+				cfag12864b_nop();
+				for (k = 0; k < CFAG12864B_ADDRESSES; k++) {
+					for (c = 0, b = 0; b < 8; b++)
+						if (cfag12864b_buffer
+							[i * CFAG12864B_ADDRESSES / 8
+							+ k / 8 + (j * 8 + b) *
+							CFAG12864B_WIDTH / 8]
+							& bit(k % 8))
+							c |= bit(b);
+					cfag12864b_writebyte(c);
+				}
+			}
+		}
+
+		memcpy(cfag12864b_cache, cfag12864b_buffer, CFAG12864B_SIZE);
+	}
+
+	if (cfag12864b_updating)
+		cfag12864b_queue();
+}
+
+/*
+ * cfag12864b Exported Symbols
+ */
+
+EXPORT_SYMBOL_GPL(cfag12864b_buffer);
+EXPORT_SYMBOL_GPL(cfag12864b_getrate);
+EXPORT_SYMBOL_GPL(cfag12864b_enable);
+EXPORT_SYMBOL_GPL(cfag12864b_disable);
+EXPORT_SYMBOL_GPL(cfag12864b_isenabled);
+
+/*
+ * Is the module inited?
+ */
+
+static unsigned char cfag12864b_inited;
+unsigned char cfag12864b_isinited(void)
+{
+	return cfag12864b_inited;
+}
+EXPORT_SYMBOL_GPL(cfag12864b_isinited);
+
+/*
+ * Module Init & Exit
+ */
+
+static int __init cfag12864b_init(void)
+{
+	int ret = -EINVAL;
+
+	/* ks0108_init() must be called first */
+	if (!ks0108_isinited()) {
+		printk(KERN_ERR CFAG12864B_NAME ": ERROR: "
+			"ks0108 is not initialized\n");
+		goto none;
+	}
+	BUILD_BUG_ON(PAGE_SIZE < CFAG12864B_SIZE);
+
+	cfag12864b_buffer = (unsigned char *) get_zeroed_page(GFP_KERNEL);
+	if (cfag12864b_buffer == NULL) {
+		printk(KERN_ERR CFAG12864B_NAME ": ERROR: "
+			"can't get a free page\n");
+		ret = -ENOMEM;
+		goto none;
+	}
+
+	cfag12864b_cache = kmalloc(CFAG12864B_SIZE,
+				   GFP_KERNEL);
+	if (cfag12864b_cache == NULL) {
+		printk(KERN_ERR CFAG12864B_NAME ": ERROR: "
+			"can't alloc cache buffer (%i bytes)\n",
+			CFAG12864B_SIZE);
+		ret = -ENOMEM;
+		goto bufferalloced;
+	}
+
+	cfag12864b_workqueue = create_singlethread_workqueue(CFAG12864B_NAME);
+	if (cfag12864b_workqueue == NULL)
+		goto cachealloced;
+
+	cfag12864b_clear();
+	cfag12864b_on();
+
+	cfag12864b_inited = 1;
+	return 0;
+
+cachealloced:
+	kfree(cfag12864b_cache);
+
+bufferalloced:
+	free_page((unsigned long) cfag12864b_buffer);
+
+none:
+	return ret;
+}
+
+static void __exit cfag12864b_exit(void)
+{
+	cfag12864b_disable();
+	cfag12864b_off();
+	destroy_workqueue(cfag12864b_workqueue);
+	kfree(cfag12864b_cache);
+	free_page((unsigned long) cfag12864b_buffer);
+}
+
+module_init(cfag12864b_init);
+module_exit(cfag12864b_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Miguel Ojeda <ojeda@kernel.org>");
+MODULE_DESCRIPTION("cfag12864b LCD driver");
diff --git a/drivers/auxdisplay/cfag12864bfb.c b/drivers/auxdisplay/cfag12864bfb.c
new file mode 100644
index 000000000..729845bcc
--- /dev/null
+++ b/drivers/auxdisplay/cfag12864bfb.c
@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *    Filename: cfag12864bfb.c
+ *     Version: 0.1.0
+ * Description: cfag12864b LCD framebuffer driver
+ *     Depends: cfag12864b
+ *
+ *      Author: Copyright (C) Miguel Ojeda <ojeda@kernel.org>
+ *        Date: 2006-10-31
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/mm.h>
+#include <linux/platform_device.h>
+#include <linux/cfag12864b.h>
+
+#define CFAG12864BFB_NAME "cfag12864bfb"
+
+static const struct fb_fix_screeninfo cfag12864bfb_fix = {
+	.id = "cfag12864b",
+	.type = FB_TYPE_PACKED_PIXELS,
+	.visual = FB_VISUAL_MONO10,
+	.xpanstep = 0,
+	.ypanstep = 0,
+	.ywrapstep = 0,
+	.line_length = CFAG12864B_WIDTH / 8,
+	.accel = FB_ACCEL_NONE,
+};
+
+static const struct fb_var_screeninfo cfag12864bfb_var = {
+	.xres = CFAG12864B_WIDTH,
+	.yres = CFAG12864B_HEIGHT,
+	.xres_virtual = CFAG12864B_WIDTH,
+	.yres_virtual = CFAG12864B_HEIGHT,
+	.bits_per_pixel = 1,
+	.red = { 0, 1, 0 },
+	.green = { 0, 1, 0 },
+	.blue = { 0, 1, 0 },
+	.left_margin = 0,
+	.right_margin = 0,
+	.upper_margin = 0,
+	.lower_margin = 0,
+	.vmode = FB_VMODE_NONINTERLACED,
+};
+
+static int cfag12864bfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
+{
+	struct page *pages = virt_to_page(cfag12864b_buffer);
+
+	return vm_map_pages_zero(vma, &pages, 1);
+}
+
+static const struct fb_ops cfag12864bfb_ops = {
+	.owner = THIS_MODULE,
+	.fb_read = fb_sys_read,
+	.fb_write = fb_sys_write,
+	.fb_fillrect = sys_fillrect,
+	.fb_copyarea = sys_copyarea,
+	.fb_imageblit = sys_imageblit,
+	.fb_mmap = cfag12864bfb_mmap,
+};
+
+static int cfag12864bfb_probe(struct platform_device *device)
+{
+	int ret = -EINVAL;
+	struct fb_info *info = framebuffer_alloc(0, &device->dev);
+
+	if (!info)
+		goto none;
+
+	info->screen_buffer = cfag12864b_buffer;
+	info->screen_size = CFAG12864B_SIZE;
+	info->fbops = &cfag12864bfb_ops;
+	info->fix = cfag12864bfb_fix;
+	info->var = cfag12864bfb_var;
+	info->pseudo_palette = NULL;
+	info->par = NULL;
+
+	if (register_framebuffer(info) < 0)
+		goto fballoced;
+
+	platform_set_drvdata(device, info);
+
+	fb_info(info, "%s frame buffer device\n", info->fix.id);
+
+	return 0;
+
+fballoced:
+	framebuffer_release(info);
+
+none:
+	return ret;
+}
+
+static int cfag12864bfb_remove(struct platform_device *device)
+{
+	struct fb_info *info = platform_get_drvdata(device);
+
+	if (info) {
+		unregister_framebuffer(info);
+		framebuffer_release(info);
+	}
+
+	return 0;
+}
+
+static struct platform_driver cfag12864bfb_driver = {
+	.probe	= cfag12864bfb_probe,
+	.remove = cfag12864bfb_remove,
+	.driver = {
+		.name	= CFAG12864BFB_NAME,
+	},
+};
+
+static struct platform_device *cfag12864bfb_device;
+
+static int __init cfag12864bfb_init(void)
+{
+	int ret = -EINVAL;
+
+	/* cfag12864b_init() must be called first */
+	if (!cfag12864b_isinited()) {
+		printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
+			"cfag12864b is not initialized\n");
+		goto none;
+	}
+
+	if (cfag12864b_enable()) {
+		printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
+			"can't enable cfag12864b refreshing (being used)\n");
+		return -ENODEV;
+	}
+
+	ret = platform_driver_register(&cfag12864bfb_driver);
+
+	if (!ret) {
+		cfag12864bfb_device =
+			platform_device_alloc(CFAG12864BFB_NAME, 0);
+
+		if (cfag12864bfb_device)
+			ret = platform_device_add(cfag12864bfb_device);
+		else
+			ret = -ENOMEM;
+
+		if (ret) {
+			platform_device_put(cfag12864bfb_device);
+			platform_driver_unregister(&cfag12864bfb_driver);
+		}
+	}
+
+none:
+	return ret;
+}
+
+static void __exit cfag12864bfb_exit(void)
+{
+	platform_device_unregister(cfag12864bfb_device);
+	platform_driver_unregister(&cfag12864bfb_driver);
+	cfag12864b_disable();
+}
+
+module_init(cfag12864bfb_init);
+module_exit(cfag12864bfb_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Miguel Ojeda <ojeda@kernel.org>");
+MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
new file mode 100644
index 000000000..6d309e497
--- /dev/null
+++ b/drivers/auxdisplay/charlcd.c
@@ -0,0 +1,681 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ */
+
+#include <linux/atomic.h>
+#include <linux/ctype.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/workqueue.h>
+
+#include <generated/utsrelease.h>
+
+#include "charlcd.h"
+
+/* Keep the backlight on this many seconds for each flash */
+#define LCD_BL_TEMPO_PERIOD	4
+
+#define LCD_ESCAPE_LEN		24	/* Max chars for LCD escape command */
+#define LCD_ESCAPE_CHAR		27	/* Use char 27 for escape command */
+
+struct charlcd_priv {
+	struct charlcd lcd;
+
+	struct delayed_work bl_work;
+	struct mutex bl_tempo_lock;	/* Protects access to bl_tempo */
+	bool bl_tempo;
+
+	bool must_clear;
+
+	/* contains the LCD config state */
+	unsigned long flags;
+
+	/* Current escape sequence and it's length or -1 if outside */
+	struct {
+		char buf[LCD_ESCAPE_LEN + 1];
+		int len;
+	} esc_seq;
+
+	unsigned long long drvdata[];
+};
+
+#define charlcd_to_priv(p)	container_of(p, struct charlcd_priv, lcd)
+
+/* Device single-open policy control */
+static atomic_t charlcd_available = ATOMIC_INIT(1);
+
+/* turn the backlight on or off */
+void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct charlcd_priv *priv = charlcd_to_priv(lcd);
+
+	if (!lcd->ops->backlight)
+		return;
+
+	mutex_lock(&priv->bl_tempo_lock);
+	if (!priv->bl_tempo)
+		lcd->ops->backlight(lcd, on);
+	mutex_unlock(&priv->bl_tempo_lock);
+}
+EXPORT_SYMBOL_GPL(charlcd_backlight);
+
+static void charlcd_bl_off(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct charlcd_priv *priv =
+		container_of(dwork, struct charlcd_priv, bl_work);
+
+	mutex_lock(&priv->bl_tempo_lock);
+	if (priv->bl_tempo) {
+		priv->bl_tempo = false;
+		if (!(priv->flags & LCD_FLAG_L))
+			priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF);
+	}
+	mutex_unlock(&priv->bl_tempo_lock);
+}
+
+/* turn the backlight on for a little while */
+void charlcd_poke(struct charlcd *lcd)
+{
+	struct charlcd_priv *priv = charlcd_to_priv(lcd);
+
+	if (!lcd->ops->backlight)
+		return;
+
+	cancel_delayed_work_sync(&priv->bl_work);
+
+	mutex_lock(&priv->bl_tempo_lock);
+	if (!priv->bl_tempo && !(priv->flags & LCD_FLAG_L))
+		lcd->ops->backlight(lcd, CHARLCD_ON);
+	priv->bl_tempo = true;
+	schedule_delayed_work(&priv->bl_work, LCD_BL_TEMPO_PERIOD * HZ);
+	mutex_unlock(&priv->bl_tempo_lock);
+}
+EXPORT_SYMBOL_GPL(charlcd_poke);
+
+static void charlcd_home(struct charlcd *lcd)
+{
+	lcd->addr.x = 0;
+	lcd->addr.y = 0;
+	lcd->ops->home(lcd);
+}
+
+static void charlcd_print(struct charlcd *lcd, char c)
+{
+	if (lcd->addr.x >= lcd->width)
+		return;
+
+	if (lcd->char_conv)
+		c = lcd->char_conv[(unsigned char)c];
+
+	if (!lcd->ops->print(lcd, c))
+		lcd->addr.x++;
+
+	/* prevents the cursor from wrapping onto the next line */
+	if (lcd->addr.x == lcd->width)
+		lcd->ops->gotoxy(lcd, lcd->addr.x - 1, lcd->addr.y);
+}
+
+static void charlcd_clear_display(struct charlcd *lcd)
+{
+	lcd->ops->clear_display(lcd);
+	lcd->addr.x = 0;
+	lcd->addr.y = 0;
+}
+
+/*
+ * Parses a movement command of the form "(.*);", where the group can be
+ * any number of subcommands of the form "(x|y)[0-9]+".
+ *
+ * Returns whether the command is valid. The position arguments are
+ * only written if the parsing was successful.
+ *
+ * For instance:
+ *   - ";"          returns (<original x>, <original y>).
+ *   - "x1;"        returns (1, <original y>).
+ *   - "y2x1;"      returns (1, 2).
+ *   - "x12y34x56;" returns (56, 34).
+ *   - ""           fails.
+ *   - "x"          fails.
+ *   - "x;"         fails.
+ *   - "x1"         fails.
+ *   - "xy12;"      fails.
+ *   - "x12yy12;"   fails.
+ *   - "xx"         fails.
+ */
+static bool parse_xy(const char *s, unsigned long *x, unsigned long *y)
+{
+	unsigned long new_x = *x;
+	unsigned long new_y = *y;
+	char *p;
+
+	for (;;) {
+		if (!*s)
+			return false;
+
+		if (*s == ';')
+			break;
+
+		if (*s == 'x') {
+			new_x = simple_strtoul(s + 1, &p, 10);
+			if (p == s + 1)
+				return false;
+			s = p;
+		} else if (*s == 'y') {
+			new_y = simple_strtoul(s + 1, &p, 10);
+			if (p == s + 1)
+				return false;
+			s = p;
+		} else {
+			return false;
+		}
+	}
+
+	*x = new_x;
+	*y = new_y;
+	return true;
+}
+
+/*
+ * These are the file operation function for user access to /dev/lcd
+ * This function can also be called from inside the kernel, by
+ * setting file and ppos to NULL.
+ *
+ */
+
+static inline int handle_lcd_special_code(struct charlcd *lcd)
+{
+	struct charlcd_priv *priv = charlcd_to_priv(lcd);
+
+	/* LCD special codes */
+
+	int processed = 0;
+
+	char *esc = priv->esc_seq.buf + 2;
+	int oldflags = priv->flags;
+
+	/* check for display mode flags */
+	switch (*esc) {
+	case 'D':	/* Display ON */
+		priv->flags |= LCD_FLAG_D;
+		if (priv->flags != oldflags)
+			lcd->ops->display(lcd, CHARLCD_ON);
+
+		processed = 1;
+		break;
+	case 'd':	/* Display OFF */
+		priv->flags &= ~LCD_FLAG_D;
+		if (priv->flags != oldflags)
+			lcd->ops->display(lcd, CHARLCD_OFF);
+
+		processed = 1;
+		break;
+	case 'C':	/* Cursor ON */
+		priv->flags |= LCD_FLAG_C;
+		if (priv->flags != oldflags)
+			lcd->ops->cursor(lcd, CHARLCD_ON);
+
+		processed = 1;
+		break;
+	case 'c':	/* Cursor OFF */
+		priv->flags &= ~LCD_FLAG_C;
+		if (priv->flags != oldflags)
+			lcd->ops->cursor(lcd, CHARLCD_OFF);
+
+		processed = 1;
+		break;
+	case 'B':	/* Blink ON */
+		priv->flags |= LCD_FLAG_B;
+		if (priv->flags != oldflags)
+			lcd->ops->blink(lcd, CHARLCD_ON);
+
+		processed = 1;
+		break;
+	case 'b':	/* Blink OFF */
+		priv->flags &= ~LCD_FLAG_B;
+		if (priv->flags != oldflags)
+			lcd->ops->blink(lcd, CHARLCD_OFF);
+
+		processed = 1;
+		break;
+	case '+':	/* Back light ON */
+		priv->flags |= LCD_FLAG_L;
+		if (priv->flags != oldflags)
+			charlcd_backlight(lcd, CHARLCD_ON);
+
+		processed = 1;
+		break;
+	case '-':	/* Back light OFF */
+		priv->flags &= ~LCD_FLAG_L;
+		if (priv->flags != oldflags)
+			charlcd_backlight(lcd, CHARLCD_OFF);
+
+		processed = 1;
+		break;
+	case '*':	/* Flash back light */
+		charlcd_poke(lcd);
+		processed = 1;
+		break;
+	case 'f':	/* Small Font */
+		priv->flags &= ~LCD_FLAG_F;
+		if (priv->flags != oldflags)
+			lcd->ops->fontsize(lcd, CHARLCD_FONTSIZE_SMALL);
+
+		processed = 1;
+		break;
+	case 'F':	/* Large Font */
+		priv->flags |= LCD_FLAG_F;
+		if (priv->flags != oldflags)
+			lcd->ops->fontsize(lcd, CHARLCD_FONTSIZE_LARGE);
+
+		processed = 1;
+		break;
+	case 'n':	/* One Line */
+		priv->flags &= ~LCD_FLAG_N;
+		if (priv->flags != oldflags)
+			lcd->ops->lines(lcd, CHARLCD_LINES_1);
+
+		processed = 1;
+		break;
+	case 'N':	/* Two Lines */
+		priv->flags |= LCD_FLAG_N;
+		if (priv->flags != oldflags)
+			lcd->ops->lines(lcd, CHARLCD_LINES_2);
+
+		processed = 1;
+		break;
+	case 'l':	/* Shift Cursor Left */
+		if (lcd->addr.x > 0) {
+			if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_LEFT))
+				lcd->addr.x--;
+		}
+
+		processed = 1;
+		break;
+	case 'r':	/* shift cursor right */
+		if (lcd->addr.x < lcd->width) {
+			if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_RIGHT))
+				lcd->addr.x++;
+		}
+
+		processed = 1;
+		break;
+	case 'L':	/* shift display left */
+		lcd->ops->shift_display(lcd, CHARLCD_SHIFT_LEFT);
+		processed = 1;
+		break;
+	case 'R':	/* shift display right */
+		lcd->ops->shift_display(lcd, CHARLCD_SHIFT_RIGHT);
+		processed = 1;
+		break;
+	case 'k': {	/* kill end of line */
+		int x, xs, ys;
+
+		xs = lcd->addr.x;
+		ys = lcd->addr.y;
+		for (x = lcd->addr.x; x < lcd->width; x++)
+			lcd->ops->print(lcd, ' ');
+
+		/* restore cursor position */
+		lcd->addr.x = xs;
+		lcd->addr.y = ys;
+		lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
+		processed = 1;
+		break;
+	}
+	case 'I':	/* reinitialize display */
+		lcd->ops->init_display(lcd);
+		priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
+			LCD_FLAG_C | LCD_FLAG_B;
+		processed = 1;
+		break;
+	case 'G':
+		if (lcd->ops->redefine_char)
+			processed = lcd->ops->redefine_char(lcd, esc);
+		else
+			processed = 1;
+		break;
+
+	case 'x':	/* gotoxy : LxXXX[yYYY]; */
+	case 'y':	/* gotoxy : LyYYY[xXXX]; */
+		if (priv->esc_seq.buf[priv->esc_seq.len - 1] != ';')
+			break;
+
+		/* If the command is valid, move to the new address */
+		if (parse_xy(esc, &lcd->addr.x, &lcd->addr.y))
+			lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
+
+		/* Regardless of its validity, mark as processed */
+		processed = 1;
+		break;
+	}
+
+	return processed;
+}
+
+static void charlcd_write_char(struct charlcd *lcd, char c)
+{
+	struct charlcd_priv *priv = charlcd_to_priv(lcd);
+
+	/* first, we'll test if we're in escape mode */
+	if ((c != '\n') && priv->esc_seq.len >= 0) {
+		/* yes, let's add this char to the buffer */
+		priv->esc_seq.buf[priv->esc_seq.len++] = c;
+		priv->esc_seq.buf[priv->esc_seq.len] = '\0';
+	} else {
+		/* aborts any previous escape sequence */
+		priv->esc_seq.len = -1;
+
+		switch (c) {
+		case LCD_ESCAPE_CHAR:
+			/* start of an escape sequence */
+			priv->esc_seq.len = 0;
+			priv->esc_seq.buf[priv->esc_seq.len] = '\0';
+			break;
+		case '\b':
+			/* go back one char and clear it */
+			if (lcd->addr.x > 0) {
+				/* back one char */
+				if (!lcd->ops->shift_cursor(lcd,
+							CHARLCD_SHIFT_LEFT))
+					lcd->addr.x--;
+			}
+			/* replace with a space */
+			charlcd_print(lcd, ' ');
+			/* back one char again */
+			if (!lcd->ops->shift_cursor(lcd, CHARLCD_SHIFT_LEFT))
+				lcd->addr.x--;
+
+			break;
+		case '\f':
+			/* quickly clear the display */
+			charlcd_clear_display(lcd);
+			break;
+		case '\n':
+			/*
+			 * flush the remainder of the current line and
+			 * go to the beginning of the next line
+			 */
+			for (; lcd->addr.x < lcd->width; lcd->addr.x++)
+				lcd->ops->print(lcd, ' ');
+
+			lcd->addr.x = 0;
+			lcd->addr.y = (lcd->addr.y + 1) % lcd->height;
+			lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
+			break;
+		case '\r':
+			/* go to the beginning of the same line */
+			lcd->addr.x = 0;
+			lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
+			break;
+		case '\t':
+			/* print a space instead of the tab */
+			charlcd_print(lcd, ' ');
+			break;
+		default:
+			/* simply print this char */
+			charlcd_print(lcd, c);
+			break;
+		}
+	}
+
+	/*
+	 * now we'll see if we're in an escape mode and if the current
+	 * escape sequence can be understood.
+	 */
+	if (priv->esc_seq.len >= 2) {
+		int processed = 0;
+
+		if (!strcmp(priv->esc_seq.buf, "[2J")) {
+			/* clear the display */
+			charlcd_clear_display(lcd);
+			processed = 1;
+		} else if (!strcmp(priv->esc_seq.buf, "[H")) {
+			/* cursor to home */
+			charlcd_home(lcd);
+			processed = 1;
+		}
+		/* codes starting with ^[[L */
+		else if ((priv->esc_seq.len >= 3) &&
+			 (priv->esc_seq.buf[0] == '[') &&
+			 (priv->esc_seq.buf[1] == 'L')) {
+			processed = handle_lcd_special_code(lcd);
+		}
+
+		/* LCD special escape codes */
+		/*
+		 * flush the escape sequence if it's been processed
+		 * or if it is getting too long.
+		 */
+		if (processed || (priv->esc_seq.len >= LCD_ESCAPE_LEN))
+			priv->esc_seq.len = -1;
+	} /* escape codes */
+}
+
+static struct charlcd *the_charlcd;
+
+static ssize_t charlcd_write(struct file *file, const char __user *buf,
+			     size_t count, loff_t *ppos)
+{
+	const char __user *tmp = buf;
+	char c;
+
+	for (; count-- > 0; (*ppos)++, tmp++) {
+		if (((count + 1) & 0x1f) == 0) {
+			/*
+			 * charlcd_write() is invoked as a VFS->write() callback
+			 * and as such it is always invoked from preemptible
+			 * context and may sleep.
+			 */
+			cond_resched();
+		}
+
+		if (get_user(c, tmp))
+			return -EFAULT;
+
+		charlcd_write_char(the_charlcd, c);
+	}
+
+	return tmp - buf;
+}
+
+static int charlcd_open(struct inode *inode, struct file *file)
+{
+	struct charlcd_priv *priv = charlcd_to_priv(the_charlcd);
+	int ret;
+
+	ret = -EBUSY;
+	if (!atomic_dec_and_test(&charlcd_available))
+		goto fail;	/* open only once at a time */
+
+	ret = -EPERM;
+	if (file->f_mode & FMODE_READ)	/* device is write-only */
+		goto fail;
+
+	if (priv->must_clear) {
+		priv->lcd.ops->clear_display(&priv->lcd);
+		priv->must_clear = false;
+		priv->lcd.addr.x = 0;
+		priv->lcd.addr.y = 0;
+	}
+	return nonseekable_open(inode, file);
+
+ fail:
+	atomic_inc(&charlcd_available);
+	return ret;
+}
+
+static int charlcd_release(struct inode *inode, struct file *file)
+{
+	atomic_inc(&charlcd_available);
+	return 0;
+}
+
+static const struct file_operations charlcd_fops = {
+	.write   = charlcd_write,
+	.open    = charlcd_open,
+	.release = charlcd_release,
+	.llseek  = no_llseek,
+};
+
+static struct miscdevice charlcd_dev = {
+	.minor	= LCD_MINOR,
+	.name	= "lcd",
+	.fops	= &charlcd_fops,
+};
+
+static void charlcd_puts(struct charlcd *lcd, const char *s)
+{
+	const char *tmp = s;
+	int count = strlen(s);
+
+	for (; count-- > 0; tmp++) {
+		if (((count + 1) & 0x1f) == 0)
+			cond_resched();
+
+		charlcd_write_char(lcd, *tmp);
+	}
+}
+
+#ifdef CONFIG_PANEL_BOOT_MESSAGE
+#define LCD_INIT_TEXT CONFIG_PANEL_BOOT_MESSAGE
+#else
+#define LCD_INIT_TEXT "Linux-" UTS_RELEASE "\n"
+#endif
+
+#ifdef CONFIG_CHARLCD_BL_ON
+#define LCD_INIT_BL "\x1b[L+"
+#elif defined(CONFIG_CHARLCD_BL_FLASH)
+#define LCD_INIT_BL "\x1b[L*"
+#else
+#define LCD_INIT_BL "\x1b[L-"
+#endif
+
+/* initialize the LCD driver */
+static int charlcd_init(struct charlcd *lcd)
+{
+	struct charlcd_priv *priv = charlcd_to_priv(lcd);
+	int ret;
+
+	priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
+		      LCD_FLAG_C | LCD_FLAG_B;
+	if (lcd->ops->backlight) {
+		mutex_init(&priv->bl_tempo_lock);
+		INIT_DELAYED_WORK(&priv->bl_work, charlcd_bl_off);
+	}
+
+	/*
+	 * before this line, we must NOT send anything to the display.
+	 * Since charlcd_init_display() needs to write data, we have to
+	 * enable mark the LCD initialized just before.
+	 */
+	if (WARN_ON(!lcd->ops->init_display))
+		return -EINVAL;
+
+	ret = lcd->ops->init_display(lcd);
+	if (ret)
+		return ret;
+
+	/* display a short message */
+	charlcd_puts(lcd, "\x1b[Lc\x1b[Lb" LCD_INIT_BL LCD_INIT_TEXT);
+
+	/* clear the display on the next device opening */
+	priv->must_clear = true;
+	charlcd_home(lcd);
+	return 0;
+}
+
+struct charlcd *charlcd_alloc(void)
+{
+	struct charlcd_priv *priv;
+	struct charlcd *lcd;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return NULL;
+
+	priv->esc_seq.len = -1;
+
+	lcd = &priv->lcd;
+
+	return lcd;
+}
+EXPORT_SYMBOL_GPL(charlcd_alloc);
+
+void charlcd_free(struct charlcd *lcd)
+{
+	kfree(charlcd_to_priv(lcd));
+}
+EXPORT_SYMBOL_GPL(charlcd_free);
+
+static int panel_notify_sys(struct notifier_block *this, unsigned long code,
+			    void *unused)
+{
+	struct charlcd *lcd = the_charlcd;
+
+	switch (code) {
+	case SYS_DOWN:
+		charlcd_puts(lcd,
+			     "\x0cReloading\nSystem...\x1b[Lc\x1b[Lb\x1b[L+");
+		break;
+	case SYS_HALT:
+		charlcd_puts(lcd, "\x0cSystem Halted.\x1b[Lc\x1b[Lb\x1b[L+");
+		break;
+	case SYS_POWER_OFF:
+		charlcd_puts(lcd, "\x0cPower off.\x1b[Lc\x1b[Lb\x1b[L+");
+		break;
+	default:
+		break;
+	}
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block panel_notifier = {
+	.notifier_call = panel_notify_sys,
+};
+
+int charlcd_register(struct charlcd *lcd)
+{
+	int ret;
+
+	ret = charlcd_init(lcd);
+	if (ret)
+		return ret;
+
+	ret = misc_register(&charlcd_dev);
+	if (ret)
+		return ret;
+
+	the_charlcd = lcd;
+	register_reboot_notifier(&panel_notifier);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(charlcd_register);
+
+int charlcd_unregister(struct charlcd *lcd)
+{
+	struct charlcd_priv *priv = charlcd_to_priv(lcd);
+
+	unregister_reboot_notifier(&panel_notifier);
+	charlcd_puts(lcd, "\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-");
+	misc_deregister(&charlcd_dev);
+	the_charlcd = NULL;
+	if (lcd->ops->backlight) {
+		cancel_delayed_work_sync(&priv->bl_work);
+		priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(charlcd_unregister);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/auxdisplay/charlcd.h b/drivers/auxdisplay/charlcd.h
new file mode 100644
index 000000000..eed80063a
--- /dev/null
+++ b/drivers/auxdisplay/charlcd.h
@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ */
+
+#ifndef _CHARLCD_H
+#define _CHARLCD_H
+
+#define LCD_FLAG_B		0x0004	/* Blink on */
+#define LCD_FLAG_C		0x0008	/* Cursor on */
+#define LCD_FLAG_D		0x0010	/* Display on */
+#define LCD_FLAG_F		0x0020	/* Large font mode */
+#define LCD_FLAG_N		0x0040	/* 2-rows mode */
+#define LCD_FLAG_L		0x0080	/* Backlight enabled */
+
+enum charlcd_onoff {
+	CHARLCD_OFF = 0,
+	CHARLCD_ON,
+};
+
+enum charlcd_shift_dir {
+	CHARLCD_SHIFT_LEFT,
+	CHARLCD_SHIFT_RIGHT,
+};
+
+enum charlcd_fontsize {
+	CHARLCD_FONTSIZE_SMALL,
+	CHARLCD_FONTSIZE_LARGE,
+};
+
+enum charlcd_lines {
+	CHARLCD_LINES_1,
+	CHARLCD_LINES_2,
+};
+
+struct charlcd {
+	const struct charlcd_ops *ops;
+	const unsigned char *char_conv;	/* Optional */
+
+	int height;
+	int width;
+
+	/* Contains the LCD X and Y offset */
+	struct {
+		unsigned long x;
+		unsigned long y;
+	} addr;
+
+	void *drvdata;
+};
+
+/**
+ * struct charlcd_ops - Functions used by charlcd. Drivers have to implement
+ * these.
+ * @backlight: Turn backlight on or off. Optional.
+ * @print: Print one character to the display at current cursor position.
+ * The buffered cursor position is advanced by charlcd. The cursor should not
+ * wrap to the next line at the end of a line.
+ * @gotoxy: Set cursor to x, y. The x and y values to set the cursor to are
+ * previously set in addr.x and addr.y by charlcd.
+ * @home: Set cursor to 0, 0. The values in addr.x and addr.y are set to 0, 0 by
+ * charlcd prior to calling this function.
+ * @clear_display: Clear the whole display and set the cursor to 0, 0. The
+ * values in addr.x and addr.y are set to 0, 0 by charlcd after to calling this
+ * function.
+ * @init_display: Initialize the display.
+ * @shift_cursor: Shift cursor left or right one position.
+ * @shift_display: Shift whole display content left or right.
+ * @display: Turn display on or off.
+ * @cursor: Turn cursor on or off.
+ * @blink: Turn cursor blink on or off.
+ * @lines: One or two lines.
+ * @redefine_char: Redefine the actual pixel matrix of character.
+ */
+struct charlcd_ops {
+	void (*backlight)(struct charlcd *lcd, enum charlcd_onoff on);
+	int (*print)(struct charlcd *lcd, int c);
+	int (*gotoxy)(struct charlcd *lcd, unsigned int x, unsigned int y);
+	int (*home)(struct charlcd *lcd);
+	int (*clear_display)(struct charlcd *lcd);
+	int (*init_display)(struct charlcd *lcd);
+	int (*shift_cursor)(struct charlcd *lcd, enum charlcd_shift_dir dir);
+	int (*shift_display)(struct charlcd *lcd, enum charlcd_shift_dir dir);
+	int (*display)(struct charlcd *lcd, enum charlcd_onoff on);
+	int (*cursor)(struct charlcd *lcd, enum charlcd_onoff on);
+	int (*blink)(struct charlcd *lcd, enum charlcd_onoff on);
+	int (*fontsize)(struct charlcd *lcd, enum charlcd_fontsize size);
+	int (*lines)(struct charlcd *lcd, enum charlcd_lines lines);
+	int (*redefine_char)(struct charlcd *lcd, char *esc);
+};
+
+void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on);
+struct charlcd *charlcd_alloc(void);
+void charlcd_free(struct charlcd *lcd);
+
+int charlcd_register(struct charlcd *lcd);
+int charlcd_unregister(struct charlcd *lcd);
+
+void charlcd_poke(struct charlcd *lcd);
+
+#endif /* CHARLCD_H */
diff --git a/drivers/auxdisplay/hd44780.c b/drivers/auxdisplay/hd44780.c
new file mode 100644
index 000000000..d56a5d508
--- /dev/null
+++ b/drivers/auxdisplay/hd44780.c
@@ -0,0 +1,353 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * HD44780 Character LCD driver for Linux
+ *
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+
+#include "charlcd.h"
+#include "hd44780_common.h"
+
+enum hd44780_pin {
+	/* Order does matter due to writing to GPIO array subsets! */
+	PIN_DATA0,	/* Optional */
+	PIN_DATA1,	/* Optional */
+	PIN_DATA2,	/* Optional */
+	PIN_DATA3,	/* Optional */
+	PIN_DATA4,
+	PIN_DATA5,
+	PIN_DATA6,
+	PIN_DATA7,
+	PIN_CTRL_RS,
+	PIN_CTRL_RW,	/* Optional */
+	PIN_CTRL_E,
+	PIN_CTRL_BL,   /* Optional */
+	PIN_NUM
+};
+
+struct hd44780 {
+	struct gpio_desc *pins[PIN_NUM];
+};
+
+static void hd44780_backlight(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+	struct hd44780 *hd = hdc->hd44780;
+
+	if (hd->pins[PIN_CTRL_BL])
+		gpiod_set_value_cansleep(hd->pins[PIN_CTRL_BL], on);
+}
+
+static void hd44780_strobe_gpio(struct hd44780 *hd)
+{
+	/* Maintain the data during 20 us before the strobe */
+	udelay(20);
+
+	gpiod_set_value_cansleep(hd->pins[PIN_CTRL_E], 1);
+
+	/* Maintain the strobe during 40 us */
+	udelay(40);
+
+	gpiod_set_value_cansleep(hd->pins[PIN_CTRL_E], 0);
+}
+
+/* write to an LCD panel register in 8 bit GPIO mode */
+static void hd44780_write_gpio8(struct hd44780 *hd, u8 val, unsigned int rs)
+{
+	DECLARE_BITMAP(values, 10); /* for DATA[0-7], RS, RW */
+	unsigned int n;
+
+	values[0] = val;
+	__assign_bit(8, values, rs);
+	n = hd->pins[PIN_CTRL_RW] ? 10 : 9;
+
+	/* Present the data to the port */
+	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA0], NULL, values);
+
+	hd44780_strobe_gpio(hd);
+}
+
+/* write to an LCD panel register in 4 bit GPIO mode */
+static void hd44780_write_gpio4(struct hd44780 *hd, u8 val, unsigned int rs)
+{
+	DECLARE_BITMAP(values, 6); /* for DATA[4-7], RS, RW */
+	unsigned int n;
+
+	/* High nibble + RS, RW */
+	values[0] = val >> 4;
+	__assign_bit(4, values, rs);
+	n = hd->pins[PIN_CTRL_RW] ? 6 : 5;
+
+	/* Present the data to the port */
+	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4], NULL, values);
+
+	hd44780_strobe_gpio(hd);
+
+	/* Low nibble */
+	values[0] &= ~0x0fUL;
+	values[0] |= val & 0x0f;
+
+	/* Present the data to the port */
+	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4], NULL, values);
+
+	hd44780_strobe_gpio(hd);
+}
+
+/* Send a command to the LCD panel in 8 bit GPIO mode */
+static void hd44780_write_cmd_gpio8(struct hd44780_common *hdc, int cmd)
+{
+	struct hd44780 *hd = hdc->hd44780;
+
+	hd44780_write_gpio8(hd, cmd, 0);
+
+	/* The shortest command takes at least 120 us */
+	udelay(120);
+}
+
+/* Send data to the LCD panel in 8 bit GPIO mode */
+static void hd44780_write_data_gpio8(struct hd44780_common *hdc, int data)
+{
+	struct hd44780 *hd = hdc->hd44780;
+
+	hd44780_write_gpio8(hd, data, 1);
+
+	/* The shortest data takes at least 45 us */
+	udelay(45);
+}
+
+static const struct charlcd_ops hd44780_ops_gpio8 = {
+	.backlight	= hd44780_backlight,
+	.print		= hd44780_common_print,
+	.gotoxy		= hd44780_common_gotoxy,
+	.home		= hd44780_common_home,
+	.clear_display	= hd44780_common_clear_display,
+	.init_display	= hd44780_common_init_display,
+	.shift_cursor	= hd44780_common_shift_cursor,
+	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
+	.cursor		= hd44780_common_cursor,
+	.blink		= hd44780_common_blink,
+	.fontsize	= hd44780_common_fontsize,
+	.lines		= hd44780_common_lines,
+	.redefine_char	= hd44780_common_redefine_char,
+};
+
+/* Send a command to the LCD panel in 4 bit GPIO mode */
+static void hd44780_write_cmd_gpio4(struct hd44780_common *hdc, int cmd)
+{
+	struct hd44780 *hd = hdc->hd44780;
+
+	hd44780_write_gpio4(hd, cmd, 0);
+
+	/* The shortest command takes at least 120 us */
+	udelay(120);
+}
+
+/* Send 4-bits of a command to the LCD panel in raw 4 bit GPIO mode */
+static void hd44780_write_cmd_raw_gpio4(struct hd44780_common *hdc, int cmd)
+{
+	DECLARE_BITMAP(values, 6); /* for DATA[4-7], RS, RW */
+	struct hd44780 *hd = hdc->hd44780;
+	unsigned int n;
+
+	/* Command nibble + RS, RW */
+	values[0] = cmd & 0x0f;
+	n = hd->pins[PIN_CTRL_RW] ? 6 : 5;
+
+	/* Present the data to the port */
+	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4], NULL, values);
+
+	hd44780_strobe_gpio(hd);
+}
+
+/* Send data to the LCD panel in 4 bit GPIO mode */
+static void hd44780_write_data_gpio4(struct hd44780_common *hdc, int data)
+{
+	struct hd44780 *hd = hdc->hd44780;
+
+	hd44780_write_gpio4(hd, data, 1);
+
+	/* The shortest data takes at least 45 us */
+	udelay(45);
+}
+
+static const struct charlcd_ops hd44780_ops_gpio4 = {
+	.backlight	= hd44780_backlight,
+	.print		= hd44780_common_print,
+	.gotoxy		= hd44780_common_gotoxy,
+	.home		= hd44780_common_home,
+	.clear_display	= hd44780_common_clear_display,
+	.init_display	= hd44780_common_init_display,
+	.shift_cursor	= hd44780_common_shift_cursor,
+	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
+	.cursor		= hd44780_common_cursor,
+	.blink		= hd44780_common_blink,
+	.fontsize	= hd44780_common_fontsize,
+	.lines		= hd44780_common_lines,
+	.redefine_char	= hd44780_common_redefine_char,
+};
+
+static int hd44780_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	unsigned int i, base;
+	struct charlcd *lcd;
+	struct hd44780_common *hdc;
+	struct hd44780 *hd;
+	int ifwidth, ret = -ENOMEM;
+
+	/* Required pins */
+	ifwidth = gpiod_count(dev, "data");
+	if (ifwidth < 0)
+		return ifwidth;
+
+	switch (ifwidth) {
+	case 4:
+		base = PIN_DATA4;
+		break;
+	case 8:
+		base = PIN_DATA0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	hdc = hd44780_common_alloc();
+	if (!hdc)
+		return -ENOMEM;
+
+	lcd = charlcd_alloc();
+	if (!lcd)
+		goto fail1;
+
+	hd = kzalloc(sizeof(struct hd44780), GFP_KERNEL);
+	if (!hd)
+		goto fail2;
+
+	hdc->hd44780 = hd;
+	lcd->drvdata = hdc;
+	for (i = 0; i < ifwidth; i++) {
+		hd->pins[base + i] = devm_gpiod_get_index(dev, "data", i,
+							  GPIOD_OUT_LOW);
+		if (IS_ERR(hd->pins[base + i])) {
+			ret = PTR_ERR(hd->pins[base + i]);
+			goto fail3;
+		}
+	}
+
+	hd->pins[PIN_CTRL_E] = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(hd->pins[PIN_CTRL_E])) {
+		ret = PTR_ERR(hd->pins[PIN_CTRL_E]);
+		goto fail3;
+	}
+
+	hd->pins[PIN_CTRL_RS] = devm_gpiod_get(dev, "rs", GPIOD_OUT_HIGH);
+	if (IS_ERR(hd->pins[PIN_CTRL_RS])) {
+		ret = PTR_ERR(hd->pins[PIN_CTRL_RS]);
+		goto fail3;
+	}
+
+	/* Optional pins */
+	hd->pins[PIN_CTRL_RW] = devm_gpiod_get_optional(dev, "rw",
+							GPIOD_OUT_LOW);
+	if (IS_ERR(hd->pins[PIN_CTRL_RW])) {
+		ret = PTR_ERR(hd->pins[PIN_CTRL_RW]);
+		goto fail3;
+	}
+
+	hd->pins[PIN_CTRL_BL] = devm_gpiod_get_optional(dev, "backlight",
+							GPIOD_OUT_LOW);
+	if (IS_ERR(hd->pins[PIN_CTRL_BL])) {
+		ret = PTR_ERR(hd->pins[PIN_CTRL_BL]);
+		goto fail3;
+	}
+
+	/* Required properties */
+	ret = device_property_read_u32(dev, "display-height-chars",
+				       &lcd->height);
+	if (ret)
+		goto fail3;
+	ret = device_property_read_u32(dev, "display-width-chars", &lcd->width);
+	if (ret)
+		goto fail3;
+
+	/*
+	 * On displays with more than two rows, the internal buffer width is
+	 * usually equal to the display width
+	 */
+	if (lcd->height > 2)
+		hdc->bwidth = lcd->width;
+
+	/* Optional properties */
+	device_property_read_u32(dev, "internal-buffer-width", &hdc->bwidth);
+
+	hdc->ifwidth = ifwidth;
+	if (ifwidth == 8) {
+		lcd->ops = &hd44780_ops_gpio8;
+		hdc->write_data = hd44780_write_data_gpio8;
+		hdc->write_cmd = hd44780_write_cmd_gpio8;
+	} else {
+		lcd->ops = &hd44780_ops_gpio4;
+		hdc->write_data = hd44780_write_data_gpio4;
+		hdc->write_cmd = hd44780_write_cmd_gpio4;
+		hdc->write_cmd_raw4 = hd44780_write_cmd_raw_gpio4;
+	}
+
+	ret = charlcd_register(lcd);
+	if (ret)
+		goto fail3;
+
+	platform_set_drvdata(pdev, lcd);
+	return 0;
+
+fail3:
+	kfree(hd);
+fail2:
+	kfree(lcd);
+fail1:
+	kfree(hdc);
+	return ret;
+}
+
+static int hd44780_remove(struct platform_device *pdev)
+{
+	struct charlcd *lcd = platform_get_drvdata(pdev);
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	charlcd_unregister(lcd);
+	kfree(hdc->hd44780);
+	kfree(lcd->drvdata);
+
+	kfree(lcd);
+	return 0;
+}
+
+static const struct of_device_id hd44780_of_match[] = {
+	{ .compatible = "hit,hd44780" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, hd44780_of_match);
+
+static struct platform_driver hd44780_driver = {
+	.probe = hd44780_probe,
+	.remove = hd44780_remove,
+	.driver		= {
+		.name	= "hd44780",
+		.of_match_table = hd44780_of_match,
+	},
+};
+
+module_platform_driver(hd44780_driver);
+MODULE_DESCRIPTION("HD44780 Character LCD driver");
+MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/auxdisplay/hd44780_common.c b/drivers/auxdisplay/hd44780_common.c
new file mode 100644
index 000000000..7cbf375b0
--- /dev/null
+++ b/drivers/auxdisplay/hd44780_common.c
@@ -0,0 +1,369 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include "charlcd.h"
+#include "hd44780_common.h"
+
+/* LCD commands */
+#define LCD_CMD_DISPLAY_CLEAR	0x01	/* Clear entire display */
+
+#define LCD_CMD_ENTRY_MODE	0x04	/* Set entry mode */
+#define LCD_CMD_CURSOR_INC	0x02	/* Increment cursor */
+
+#define LCD_CMD_DISPLAY_CTRL	0x08	/* Display control */
+#define LCD_CMD_DISPLAY_ON	0x04	/* Set display on */
+#define LCD_CMD_CURSOR_ON	0x02	/* Set cursor on */
+#define LCD_CMD_BLINK_ON	0x01	/* Set blink on */
+
+#define LCD_CMD_SHIFT		0x10	/* Shift cursor/display */
+#define LCD_CMD_DISPLAY_SHIFT	0x08	/* Shift display instead of cursor */
+#define LCD_CMD_SHIFT_RIGHT	0x04	/* Shift display/cursor to the right */
+
+#define LCD_CMD_FUNCTION_SET	0x20	/* Set function */
+#define LCD_CMD_DATA_LEN_8BITS	0x10	/* Set data length to 8 bits */
+#define LCD_CMD_TWO_LINES	0x08	/* Set to two display lines */
+#define LCD_CMD_FONT_5X10_DOTS	0x04	/* Set char font to 5x10 dots */
+
+#define LCD_CMD_SET_CGRAM_ADDR	0x40	/* Set char generator RAM address */
+
+#define LCD_CMD_SET_DDRAM_ADDR	0x80	/* Set display data RAM address */
+
+/* sleeps that many milliseconds with a reschedule */
+static void long_sleep(int ms)
+{
+	schedule_timeout_interruptible(msecs_to_jiffies(ms));
+}
+
+int hd44780_common_print(struct charlcd *lcd, int c)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (lcd->addr.x < hdc->bwidth) {
+		hdc->write_data(hdc, c);
+		return 0;
+	}
+
+	return 1;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_print);
+
+int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+	unsigned int addr;
+
+	/*
+	 * we force the cursor to stay at the end of the
+	 * line if it wants to go farther
+	 */
+	addr = x < hdc->bwidth ? x & (hdc->hwidth - 1) : hdc->bwidth - 1;
+	if (y & 1)
+		addr += hdc->hwidth;
+	if (y & 2)
+		addr += hdc->bwidth;
+	hdc->write_cmd(hdc, LCD_CMD_SET_DDRAM_ADDR | addr);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_gotoxy);
+
+int hd44780_common_home(struct charlcd *lcd)
+{
+	return hd44780_common_gotoxy(lcd, 0, 0);
+}
+EXPORT_SYMBOL_GPL(hd44780_common_home);
+
+/* clears the display and resets X/Y */
+int hd44780_common_clear_display(struct charlcd *lcd)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);
+	/* datasheet says to wait 1,64 milliseconds */
+	long_sleep(2);
+
+	/*
+	 * The Hitachi HD44780 controller (and compatible ones) reset the DDRAM
+	 * address when executing the DISPLAY_CLEAR command, thus the
+	 * following call is not required. However, other controllers do not
+	 * (e.g. NewHaven NHD-0220DZW-AG5), thus move the cursor to home
+	 * unconditionally to support both.
+	 */
+	return hd44780_common_home(lcd);
+}
+EXPORT_SYMBOL_GPL(hd44780_common_clear_display);
+
+int hd44780_common_init_display(struct charlcd *lcd)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
+	u8 init;
+
+	if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
+		return -EINVAL;
+
+	hdc->hd44780_common_flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) |
+		LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;
+
+	long_sleep(20);		/* wait 20 ms after power-up for the paranoid */
+
+	/*
+	 * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
+	 * the LCD is in 8-bit mode afterwards
+	 */
+	init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
+	if (hdc->ifwidth == 4) {
+		init >>= 4;
+		write_cmd_raw = hdc->write_cmd_raw4;
+	} else {
+		write_cmd_raw = hdc->write_cmd;
+	}
+	write_cmd_raw(hdc, init);
+	long_sleep(10);
+	write_cmd_raw(hdc, init);
+	long_sleep(10);
+	write_cmd_raw(hdc, init);
+	long_sleep(10);
+
+	if (hdc->ifwidth == 4) {
+		/* Switch to 4-bit mode, 1 line, small fonts */
+		hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
+		long_sleep(10);
+	}
+
+	/* set font height and lines number */
+	hdc->write_cmd(hdc,
+		LCD_CMD_FUNCTION_SET |
+		((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_F) ?
+			LCD_CMD_FONT_5X10_DOTS : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_N) ?
+			LCD_CMD_TWO_LINES : 0));
+	long_sleep(10);
+
+	/* display off, cursor off, blink off */
+	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
+	long_sleep(10);
+
+	hdc->write_cmd(hdc,
+		LCD_CMD_DISPLAY_CTRL |	/* set display mode */
+		((hdc->hd44780_common_flags & LCD_FLAG_D) ?
+			LCD_CMD_DISPLAY_ON : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_C) ?
+			LCD_CMD_CURSOR_ON : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_B) ?
+			LCD_CMD_BLINK_ON : 0));
+
+	charlcd_backlight(lcd,
+			(hdc->hd44780_common_flags & LCD_FLAG_L) ? 1 : 0);
+
+	long_sleep(10);
+
+	/* entry mode set : increment, cursor shifting */
+	hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
+
+	hd44780_common_clear_display(lcd);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_init_display);
+
+int hd44780_common_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (dir == CHARLCD_SHIFT_LEFT) {
+		/* back one char if not at end of line */
+		if (lcd->addr.x < hdc->bwidth)
+			hdc->write_cmd(hdc, LCD_CMD_SHIFT);
+	} else if (dir == CHARLCD_SHIFT_RIGHT) {
+		/* allow the cursor to pass the end of the line */
+		if (lcd->addr.x < (hdc->bwidth - 1))
+			hdc->write_cmd(hdc,
+					LCD_CMD_SHIFT | LCD_CMD_SHIFT_RIGHT);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor);
+
+int hd44780_common_shift_display(struct charlcd *lcd,
+		enum charlcd_shift_dir dir)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (dir == CHARLCD_SHIFT_LEFT)
+		hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
+	else if (dir == CHARLCD_SHIFT_RIGHT)
+		hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
+			LCD_CMD_SHIFT_RIGHT);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_shift_display);
+
+static void hd44780_common_set_mode(struct hd44780_common *hdc)
+{
+	hdc->write_cmd(hdc,
+		LCD_CMD_DISPLAY_CTRL |
+		((hdc->hd44780_common_flags & LCD_FLAG_D) ?
+			LCD_CMD_DISPLAY_ON : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_C) ?
+			LCD_CMD_CURSOR_ON : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_B) ?
+			LCD_CMD_BLINK_ON : 0));
+}
+
+int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (on == CHARLCD_ON)
+		hdc->hd44780_common_flags |= LCD_FLAG_D;
+	else
+		hdc->hd44780_common_flags &= ~LCD_FLAG_D;
+
+	hd44780_common_set_mode(hdc);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_display);
+
+int hd44780_common_cursor(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (on == CHARLCD_ON)
+		hdc->hd44780_common_flags |= LCD_FLAG_C;
+	else
+		hdc->hd44780_common_flags &= ~LCD_FLAG_C;
+
+	hd44780_common_set_mode(hdc);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_cursor);
+
+int hd44780_common_blink(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (on == CHARLCD_ON)
+		hdc->hd44780_common_flags |= LCD_FLAG_B;
+	else
+		hdc->hd44780_common_flags &= ~LCD_FLAG_B;
+
+	hd44780_common_set_mode(hdc);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_blink);
+
+static void hd44780_common_set_function(struct hd44780_common *hdc)
+{
+	hdc->write_cmd(hdc,
+		LCD_CMD_FUNCTION_SET |
+		((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_F) ?
+			LCD_CMD_FONT_5X10_DOTS : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_N) ?
+			LCD_CMD_TWO_LINES : 0));
+}
+
+int hd44780_common_fontsize(struct charlcd *lcd, enum charlcd_fontsize size)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (size == CHARLCD_FONTSIZE_LARGE)
+		hdc->hd44780_common_flags |= LCD_FLAG_F;
+	else
+		hdc->hd44780_common_flags &= ~LCD_FLAG_F;
+
+	hd44780_common_set_function(hdc);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_fontsize);
+
+int hd44780_common_lines(struct charlcd *lcd, enum charlcd_lines lines)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (lines == CHARLCD_LINES_2)
+		hdc->hd44780_common_flags |= LCD_FLAG_N;
+	else
+		hdc->hd44780_common_flags &= ~LCD_FLAG_N;
+
+	hd44780_common_set_function(hdc);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_lines);
+
+int hd44780_common_redefine_char(struct charlcd *lcd, char *esc)
+{
+	/* Generator : LGcxxxxx...xx; must have <c> between '0'
+	 * and '7', representing the numerical ASCII code of the
+	 * redefined character, and <xx...xx> a sequence of 16
+	 * hex digits representing 8 bytes for each character.
+	 * Most LCDs will only use 5 lower bits of the 7 first
+	 * bytes.
+	 */
+
+	struct hd44780_common *hdc = lcd->drvdata;
+	unsigned char cgbytes[8];
+	unsigned char cgaddr;
+	int cgoffset;
+	int shift;
+	char value;
+	int addr;
+
+	if (!strchr(esc, ';'))
+		return 0;
+
+	esc++;
+
+	cgaddr = *(esc++) - '0';
+	if (cgaddr > 7)
+		return 1;
+
+	cgoffset = 0;
+	shift = 0;
+	value = 0;
+	while (*esc && cgoffset < 8) {
+		int half;
+
+		shift ^= 4;
+		half = hex_to_bin(*esc++);
+		if (half < 0)
+			continue;
+
+		value |= half << shift;
+		if (shift == 0) {
+			cgbytes[cgoffset++] = value;
+			value = 0;
+		}
+	}
+
+	hdc->write_cmd(hdc, LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
+	for (addr = 0; addr < cgoffset; addr++)
+		hdc->write_data(hdc, cgbytes[addr]);
+
+	/* ensures that we stop writing to CGRAM */
+	lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
+	return 1;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_redefine_char);
+
+struct hd44780_common *hd44780_common_alloc(void)
+{
+	struct hd44780_common *hd;
+
+	hd = kzalloc(sizeof(*hd), GFP_KERNEL);
+	if (!hd)
+		return NULL;
+
+	hd->ifwidth = 8;
+	hd->bwidth = DEFAULT_LCD_BWIDTH;
+	hd->hwidth = DEFAULT_LCD_HWIDTH;
+	return hd;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_alloc);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/auxdisplay/hd44780_common.h b/drivers/auxdisplay/hd44780_common.h
new file mode 100644
index 000000000..a16aa8c29
--- /dev/null
+++ b/drivers/auxdisplay/hd44780_common.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#define DEFAULT_LCD_BWIDTH      40
+#define DEFAULT_LCD_HWIDTH      64
+
+struct hd44780_common {
+	int ifwidth;			/* 4-bit or 8-bit (default) */
+	int bwidth;			/* Default set by hd44780_alloc() */
+	int hwidth;			/* Default set by hd44780_alloc() */
+	unsigned long hd44780_common_flags;
+	void (*write_data)(struct hd44780_common *hdc, int data);
+	void (*write_cmd)(struct hd44780_common *hdc, int cmd);
+	/* write_cmd_raw4 is for 4-bit connected displays only */
+	void (*write_cmd_raw4)(struct hd44780_common *hdc, int cmd);
+	void *hd44780;
+};
+
+int hd44780_common_print(struct charlcd *lcd, int c);
+int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y);
+int hd44780_common_home(struct charlcd *lcd);
+int hd44780_common_clear_display(struct charlcd *lcd);
+int hd44780_common_init_display(struct charlcd *lcd);
+int hd44780_common_shift_cursor(struct charlcd *lcd,
+		enum charlcd_shift_dir dir);
+int hd44780_common_shift_display(struct charlcd *lcd,
+		enum charlcd_shift_dir dir);
+int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on);
+int hd44780_common_cursor(struct charlcd *lcd, enum charlcd_onoff on);
+int hd44780_common_blink(struct charlcd *lcd, enum charlcd_onoff on);
+int hd44780_common_fontsize(struct charlcd *lcd, enum charlcd_fontsize size);
+int hd44780_common_lines(struct charlcd *lcd, enum charlcd_lines lines);
+int hd44780_common_redefine_char(struct charlcd *lcd, char *esc);
+struct hd44780_common *hd44780_common_alloc(void);
diff --git a/drivers/auxdisplay/ht16k33.c b/drivers/auxdisplay/ht16k33.c
new file mode 100644
index 000000000..3a2d88387
--- /dev/null
+++ b/drivers/auxdisplay/ht16k33.c
@@ -0,0 +1,834 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * HT16K33 driver
+ *
+ * Author: Robin van der Gracht <robin@protonic.nl>
+ *
+ * Copyright: (C) 2016 Protonic Holland.
+ * Copyright (C) 2021 Glider bv
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/i2c.h>
+#include <linux/property.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+#include <linux/input.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/leds.h>
+#include <linux/workqueue.h>
+#include <linux/mm.h>
+
+#include <linux/map_to_7segment.h>
+#include <linux/map_to_14segment.h>
+
+#include <asm/unaligned.h>
+
+#include "line-display.h"
+
+/* Registers */
+#define REG_SYSTEM_SETUP		0x20
+#define REG_SYSTEM_SETUP_OSC_ON		BIT(0)
+
+#define REG_DISPLAY_SETUP		0x80
+#define REG_DISPLAY_SETUP_ON		BIT(0)
+#define REG_DISPLAY_SETUP_BLINK_OFF	(0 << 1)
+#define REG_DISPLAY_SETUP_BLINK_2HZ	(1 << 1)
+#define REG_DISPLAY_SETUP_BLINK_1HZ	(2 << 1)
+#define REG_DISPLAY_SETUP_BLINK_0HZ5	(3 << 1)
+
+#define REG_ROWINT_SET			0xA0
+#define REG_ROWINT_SET_INT_EN		BIT(0)
+#define REG_ROWINT_SET_INT_ACT_HIGH	BIT(1)
+
+#define REG_BRIGHTNESS			0xE0
+
+/* Defines */
+#define DRIVER_NAME			"ht16k33"
+
+#define MIN_BRIGHTNESS			0x1
+#define MAX_BRIGHTNESS			0x10
+
+#define HT16K33_MATRIX_LED_MAX_COLS	8
+#define HT16K33_MATRIX_LED_MAX_ROWS	16
+#define HT16K33_MATRIX_KEYPAD_MAX_COLS	3
+#define HT16K33_MATRIX_KEYPAD_MAX_ROWS	12
+
+#define BYTES_PER_ROW		(HT16K33_MATRIX_LED_MAX_ROWS / 8)
+#define HT16K33_FB_SIZE		(HT16K33_MATRIX_LED_MAX_COLS * BYTES_PER_ROW)
+
+enum display_type {
+	DISP_MATRIX = 0,
+	DISP_QUAD_7SEG,
+	DISP_QUAD_14SEG,
+};
+
+struct ht16k33_keypad {
+	struct i2c_client *client;
+	struct input_dev *dev;
+	uint32_t cols;
+	uint32_t rows;
+	uint32_t row_shift;
+	uint32_t debounce_ms;
+	uint16_t last_key_state[HT16K33_MATRIX_KEYPAD_MAX_COLS];
+
+	wait_queue_head_t wait;
+	bool stopped;
+};
+
+struct ht16k33_fbdev {
+	struct fb_info *info;
+	uint32_t refresh_rate;
+	uint8_t *buffer;
+	uint8_t *cache;
+};
+
+struct ht16k33_seg {
+	struct linedisp linedisp;
+	union {
+		struct seg7_conversion_map seg7;
+		struct seg14_conversion_map seg14;
+	} map;
+	unsigned int map_size;
+	char curr[4];
+};
+
+struct ht16k33_priv {
+	struct i2c_client *client;
+	struct delayed_work work;
+	struct led_classdev led;
+	struct ht16k33_keypad keypad;
+	union {
+		struct ht16k33_fbdev fbdev;
+		struct ht16k33_seg seg;
+	};
+	enum display_type type;
+	uint8_t blink;
+};
+
+static const struct fb_fix_screeninfo ht16k33_fb_fix = {
+	.id		= DRIVER_NAME,
+	.type		= FB_TYPE_PACKED_PIXELS,
+	.visual		= FB_VISUAL_MONO10,
+	.xpanstep	= 0,
+	.ypanstep	= 0,
+	.ywrapstep	= 0,
+	.line_length	= HT16K33_MATRIX_LED_MAX_ROWS,
+	.accel		= FB_ACCEL_NONE,
+};
+
+static const struct fb_var_screeninfo ht16k33_fb_var = {
+	.xres = HT16K33_MATRIX_LED_MAX_ROWS,
+	.yres = HT16K33_MATRIX_LED_MAX_COLS,
+	.xres_virtual = HT16K33_MATRIX_LED_MAX_ROWS,
+	.yres_virtual = HT16K33_MATRIX_LED_MAX_COLS,
+	.bits_per_pixel = 1,
+	.red = { 0, 1, 0 },
+	.green = { 0, 1, 0 },
+	.blue = { 0, 1, 0 },
+	.left_margin = 0,
+	.right_margin = 0,
+	.upper_margin = 0,
+	.lower_margin = 0,
+	.vmode = FB_VMODE_NONINTERLACED,
+};
+
+static const SEG7_DEFAULT_MAP(initial_map_seg7);
+static const SEG14_DEFAULT_MAP(initial_map_seg14);
+
+static ssize_t map_seg_show(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	struct ht16k33_priv *priv = dev_get_drvdata(dev);
+
+	memcpy(buf, &priv->seg.map, priv->seg.map_size);
+	return priv->seg.map_size;
+}
+
+static ssize_t map_seg_store(struct device *dev, struct device_attribute *attr,
+			     const char *buf, size_t cnt)
+{
+	struct ht16k33_priv *priv = dev_get_drvdata(dev);
+
+	if (cnt != priv->seg.map_size)
+		return -EINVAL;
+
+	memcpy(&priv->seg.map, buf, cnt);
+	return cnt;
+}
+
+static DEVICE_ATTR(map_seg7, 0644, map_seg_show, map_seg_store);
+static DEVICE_ATTR(map_seg14, 0644, map_seg_show, map_seg_store);
+
+static int ht16k33_display_on(struct ht16k33_priv *priv)
+{
+	uint8_t data = REG_DISPLAY_SETUP | REG_DISPLAY_SETUP_ON | priv->blink;
+
+	return i2c_smbus_write_byte(priv->client, data);
+}
+
+static int ht16k33_display_off(struct ht16k33_priv *priv)
+{
+	return i2c_smbus_write_byte(priv->client, REG_DISPLAY_SETUP);
+}
+
+static int ht16k33_brightness_set(struct ht16k33_priv *priv,
+				  unsigned int brightness)
+{
+	int err;
+
+	if (brightness == 0) {
+		priv->blink = REG_DISPLAY_SETUP_BLINK_OFF;
+		return ht16k33_display_off(priv);
+	}
+
+	err = ht16k33_display_on(priv);
+	if (err)
+		return err;
+
+	return i2c_smbus_write_byte(priv->client,
+				    REG_BRIGHTNESS | (brightness - 1));
+}
+
+static int ht16k33_brightness_set_blocking(struct led_classdev *led_cdev,
+					   enum led_brightness brightness)
+{
+	struct ht16k33_priv *priv = container_of(led_cdev, struct ht16k33_priv,
+						 led);
+
+	return ht16k33_brightness_set(priv, brightness);
+}
+
+static int ht16k33_blink_set(struct led_classdev *led_cdev,
+			     unsigned long *delay_on, unsigned long *delay_off)
+{
+	struct ht16k33_priv *priv = container_of(led_cdev, struct ht16k33_priv,
+						 led);
+	unsigned int delay;
+	uint8_t blink;
+	int err;
+
+	if (!*delay_on && !*delay_off) {
+		blink = REG_DISPLAY_SETUP_BLINK_1HZ;
+		delay = 1000;
+	} else if (*delay_on <= 750) {
+		blink = REG_DISPLAY_SETUP_BLINK_2HZ;
+		delay = 500;
+	} else if (*delay_on <= 1500) {
+		blink = REG_DISPLAY_SETUP_BLINK_1HZ;
+		delay = 1000;
+	} else {
+		blink = REG_DISPLAY_SETUP_BLINK_0HZ5;
+		delay = 2000;
+	}
+
+	err = i2c_smbus_write_byte(priv->client,
+				   REG_DISPLAY_SETUP | REG_DISPLAY_SETUP_ON |
+				   blink);
+	if (err)
+		return err;
+
+	priv->blink = blink;
+	*delay_on = *delay_off = delay;
+	return 0;
+}
+
+static void ht16k33_fb_queue(struct ht16k33_priv *priv)
+{
+	struct ht16k33_fbdev *fbdev = &priv->fbdev;
+
+	schedule_delayed_work(&priv->work, HZ / fbdev->refresh_rate);
+}
+
+/*
+ * This gets the fb data from cache and copies it to ht16k33 display RAM
+ */
+static void ht16k33_fb_update(struct work_struct *work)
+{
+	struct ht16k33_priv *priv = container_of(work, struct ht16k33_priv,
+						 work.work);
+	struct ht16k33_fbdev *fbdev = &priv->fbdev;
+
+	uint8_t *p1, *p2;
+	int len, pos = 0, first = -1;
+
+	p1 = fbdev->cache;
+	p2 = fbdev->buffer;
+
+	/* Search for the first byte with changes */
+	while (pos < HT16K33_FB_SIZE && first < 0) {
+		if (*(p1++) - *(p2++))
+			first = pos;
+		pos++;
+	}
+
+	/* No changes found */
+	if (first < 0)
+		goto requeue;
+
+	len = HT16K33_FB_SIZE - first;
+	p1 = fbdev->cache + HT16K33_FB_SIZE - 1;
+	p2 = fbdev->buffer + HT16K33_FB_SIZE - 1;
+
+	/* Determine i2c transfer length */
+	while (len > 1) {
+		if (*(p1--) - *(p2--))
+			break;
+		len--;
+	}
+
+	p1 = fbdev->cache + first;
+	p2 = fbdev->buffer + first;
+	if (!i2c_smbus_write_i2c_block_data(priv->client, first, len, p2))
+		memcpy(p1, p2, len);
+requeue:
+	ht16k33_fb_queue(priv);
+}
+
+static int ht16k33_initialize(struct ht16k33_priv *priv)
+{
+	uint8_t data[HT16K33_FB_SIZE];
+	uint8_t byte;
+	int err;
+
+	/* Clear RAM (8 * 16 bits) */
+	memset(data, 0, sizeof(data));
+	err = i2c_smbus_write_block_data(priv->client, 0, sizeof(data), data);
+	if (err)
+		return err;
+
+	/* Turn on internal oscillator */
+	byte = REG_SYSTEM_SETUP_OSC_ON | REG_SYSTEM_SETUP;
+	err = i2c_smbus_write_byte(priv->client, byte);
+	if (err)
+		return err;
+
+	/* Configure INT pin */
+	byte = REG_ROWINT_SET | REG_ROWINT_SET_INT_ACT_HIGH;
+	if (priv->client->irq > 0)
+		byte |= REG_ROWINT_SET_INT_EN;
+	return i2c_smbus_write_byte(priv->client, byte);
+}
+
+static int ht16k33_bl_update_status(struct backlight_device *bl)
+{
+	int brightness = bl->props.brightness;
+	struct ht16k33_priv *priv = bl_get_data(bl);
+
+	if (bl->props.power != FB_BLANK_UNBLANK ||
+	    bl->props.fb_blank != FB_BLANK_UNBLANK ||
+	    bl->props.state & BL_CORE_FBBLANK)
+		brightness = 0;
+
+	return ht16k33_brightness_set(priv, brightness);
+}
+
+static int ht16k33_bl_check_fb(struct backlight_device *bl, struct fb_info *fi)
+{
+	struct ht16k33_priv *priv = bl_get_data(bl);
+
+	return (fi == NULL) || (fi->par == priv);
+}
+
+static const struct backlight_ops ht16k33_bl_ops = {
+	.update_status	= ht16k33_bl_update_status,
+	.check_fb	= ht16k33_bl_check_fb,
+};
+
+/*
+ * Blank events will be passed to the actual device handling the backlight when
+ * we return zero here.
+ */
+static int ht16k33_blank(int blank, struct fb_info *info)
+{
+	return 0;
+}
+
+static int ht16k33_mmap(struct fb_info *info, struct vm_area_struct *vma)
+{
+	struct ht16k33_priv *priv = info->par;
+	struct page *pages = virt_to_page(priv->fbdev.buffer);
+
+	return vm_map_pages_zero(vma, &pages, 1);
+}
+
+static const struct fb_ops ht16k33_fb_ops = {
+	.owner = THIS_MODULE,
+	.fb_read = fb_sys_read,
+	.fb_write = fb_sys_write,
+	.fb_blank = ht16k33_blank,
+	.fb_fillrect = sys_fillrect,
+	.fb_copyarea = sys_copyarea,
+	.fb_imageblit = sys_imageblit,
+	.fb_mmap = ht16k33_mmap,
+};
+
+/*
+ * This gets the keys from keypad and reports it to input subsystem.
+ * Returns true if a key is pressed.
+ */
+static bool ht16k33_keypad_scan(struct ht16k33_keypad *keypad)
+{
+	const unsigned short *keycodes = keypad->dev->keycode;
+	u16 new_state[HT16K33_MATRIX_KEYPAD_MAX_COLS];
+	__le16 data[HT16K33_MATRIX_KEYPAD_MAX_COLS];
+	unsigned long bits_changed;
+	int row, col, code;
+	int rc;
+	bool pressed = false;
+
+	rc = i2c_smbus_read_i2c_block_data(keypad->client, 0x40,
+					   sizeof(data), (u8 *)data);
+	if (rc != sizeof(data)) {
+		dev_err(&keypad->client->dev,
+			"Failed to read key data, rc=%d\n", rc);
+		return false;
+	}
+
+	for (col = 0; col < keypad->cols; col++) {
+		new_state[col] = le16_to_cpu(data[col]);
+		if (new_state[col])
+			pressed = true;
+		bits_changed = keypad->last_key_state[col] ^ new_state[col];
+
+		for_each_set_bit(row, &bits_changed, BITS_PER_LONG) {
+			code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
+			input_event(keypad->dev, EV_MSC, MSC_SCAN, code);
+			input_report_key(keypad->dev, keycodes[code],
+					 new_state[col] & BIT(row));
+		}
+	}
+	input_sync(keypad->dev);
+	memcpy(keypad->last_key_state, new_state, sizeof(u16) * keypad->cols);
+
+	return pressed;
+}
+
+static irqreturn_t ht16k33_keypad_irq_thread(int irq, void *dev)
+{
+	struct ht16k33_keypad *keypad = dev;
+
+	do {
+		wait_event_timeout(keypad->wait, keypad->stopped,
+				    msecs_to_jiffies(keypad->debounce_ms));
+		if (keypad->stopped)
+			break;
+	} while (ht16k33_keypad_scan(keypad));
+
+	return IRQ_HANDLED;
+}
+
+static int ht16k33_keypad_start(struct input_dev *dev)
+{
+	struct ht16k33_keypad *keypad = input_get_drvdata(dev);
+
+	keypad->stopped = false;
+	mb();
+	enable_irq(keypad->client->irq);
+
+	return 0;
+}
+
+static void ht16k33_keypad_stop(struct input_dev *dev)
+{
+	struct ht16k33_keypad *keypad = input_get_drvdata(dev);
+
+	keypad->stopped = true;
+	mb();
+	wake_up(&keypad->wait);
+	disable_irq(keypad->client->irq);
+}
+
+static void ht16k33_linedisp_update(struct linedisp *linedisp)
+{
+	struct ht16k33_priv *priv = container_of(linedisp, struct ht16k33_priv,
+						 seg.linedisp);
+
+	schedule_delayed_work(&priv->work, 0);
+}
+
+static void ht16k33_seg7_update(struct work_struct *work)
+{
+	struct ht16k33_priv *priv = container_of(work, struct ht16k33_priv,
+						 work.work);
+	struct ht16k33_seg *seg = &priv->seg;
+	char *s = seg->curr;
+	uint8_t buf[9];
+
+	buf[0] = map_to_seg7(&seg->map.seg7, *s++);
+	buf[1] = 0;
+	buf[2] = map_to_seg7(&seg->map.seg7, *s++);
+	buf[3] = 0;
+	buf[4] = 0;
+	buf[5] = 0;
+	buf[6] = map_to_seg7(&seg->map.seg7, *s++);
+	buf[7] = 0;
+	buf[8] = map_to_seg7(&seg->map.seg7, *s++);
+
+	i2c_smbus_write_i2c_block_data(priv->client, 0, ARRAY_SIZE(buf), buf);
+}
+
+static void ht16k33_seg14_update(struct work_struct *work)
+{
+	struct ht16k33_priv *priv = container_of(work, struct ht16k33_priv,
+						 work.work);
+	struct ht16k33_seg *seg = &priv->seg;
+	char *s = seg->curr;
+	uint8_t buf[8];
+
+	put_unaligned_le16(map_to_seg14(&seg->map.seg14, *s++), buf);
+	put_unaligned_le16(map_to_seg14(&seg->map.seg14, *s++), buf + 2);
+	put_unaligned_le16(map_to_seg14(&seg->map.seg14, *s++), buf + 4);
+	put_unaligned_le16(map_to_seg14(&seg->map.seg14, *s++), buf + 6);
+
+	i2c_smbus_write_i2c_block_data(priv->client, 0, ARRAY_SIZE(buf), buf);
+}
+
+static int ht16k33_led_probe(struct device *dev, struct led_classdev *led,
+			     unsigned int brightness)
+{
+	struct led_init_data init_data = {};
+	int err;
+
+	/* The LED is optional */
+	init_data.fwnode = device_get_named_child_node(dev, "led");
+	if (!init_data.fwnode)
+		return 0;
+
+	init_data.devicename = "auxdisplay";
+	init_data.devname_mandatory = true;
+
+	led->brightness_set_blocking = ht16k33_brightness_set_blocking;
+	led->blink_set = ht16k33_blink_set;
+	led->flags = LED_CORE_SUSPENDRESUME;
+	led->brightness = brightness;
+	led->max_brightness = MAX_BRIGHTNESS;
+
+	err = devm_led_classdev_register_ext(dev, led, &init_data);
+	if (err)
+		dev_err(dev, "Failed to register LED\n");
+
+	return err;
+}
+
+static int ht16k33_keypad_probe(struct i2c_client *client,
+				struct ht16k33_keypad *keypad)
+{
+	struct device *dev = &client->dev;
+	u32 rows = HT16K33_MATRIX_KEYPAD_MAX_ROWS;
+	u32 cols = HT16K33_MATRIX_KEYPAD_MAX_COLS;
+	int err;
+
+	keypad->client = client;
+	init_waitqueue_head(&keypad->wait);
+
+	keypad->dev = devm_input_allocate_device(dev);
+	if (!keypad->dev)
+		return -ENOMEM;
+
+	input_set_drvdata(keypad->dev, keypad);
+
+	keypad->dev->name = DRIVER_NAME"-keypad";
+	keypad->dev->id.bustype = BUS_I2C;
+	keypad->dev->open = ht16k33_keypad_start;
+	keypad->dev->close = ht16k33_keypad_stop;
+
+	if (!device_property_read_bool(dev, "linux,no-autorepeat"))
+		__set_bit(EV_REP, keypad->dev->evbit);
+
+	err = device_property_read_u32(dev, "debounce-delay-ms",
+				       &keypad->debounce_ms);
+	if (err) {
+		dev_err(dev, "key debounce delay not specified\n");
+		return err;
+	}
+
+	err = matrix_keypad_parse_properties(dev, &rows, &cols);
+	if (err)
+		return err;
+	if (rows > HT16K33_MATRIX_KEYPAD_MAX_ROWS ||
+	    cols > HT16K33_MATRIX_KEYPAD_MAX_COLS) {
+		dev_err(dev, "%u rows or %u cols out of range in DT\n", rows,
+			cols);
+		return -ERANGE;
+	}
+
+	keypad->rows = rows;
+	keypad->cols = cols;
+	keypad->row_shift = get_count_order(cols);
+
+	err = matrix_keypad_build_keymap(NULL, NULL, rows, cols, NULL,
+					 keypad->dev);
+	if (err) {
+		dev_err(dev, "failed to build keymap\n");
+		return err;
+	}
+
+	err = devm_request_threaded_irq(dev, client->irq, NULL,
+					ht16k33_keypad_irq_thread,
+					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+					DRIVER_NAME, keypad);
+	if (err) {
+		dev_err(dev, "irq request failed %d, error %d\n", client->irq,
+			err);
+		return err;
+	}
+
+	ht16k33_keypad_stop(keypad->dev);
+
+	return input_register_device(keypad->dev);
+}
+
+static int ht16k33_fbdev_probe(struct device *dev, struct ht16k33_priv *priv,
+			       uint32_t brightness)
+{
+	struct ht16k33_fbdev *fbdev = &priv->fbdev;
+	struct backlight_device *bl = NULL;
+	int err;
+
+	if (priv->led.dev) {
+		err = ht16k33_brightness_set(priv, brightness);
+		if (err)
+			return err;
+	} else {
+		/* backwards compatibility with DT lacking an led subnode */
+		struct backlight_properties bl_props;
+
+		memset(&bl_props, 0, sizeof(struct backlight_properties));
+		bl_props.type = BACKLIGHT_RAW;
+		bl_props.max_brightness = MAX_BRIGHTNESS;
+
+		bl = devm_backlight_device_register(dev, DRIVER_NAME"-bl", dev,
+						    priv, &ht16k33_bl_ops,
+						    &bl_props);
+		if (IS_ERR(bl)) {
+			dev_err(dev, "failed to register backlight\n");
+			return PTR_ERR(bl);
+		}
+
+		bl->props.brightness = brightness;
+		ht16k33_bl_update_status(bl);
+	}
+
+	/* Framebuffer (2 bytes per column) */
+	BUILD_BUG_ON(PAGE_SIZE < HT16K33_FB_SIZE);
+	fbdev->buffer = (unsigned char *) get_zeroed_page(GFP_KERNEL);
+	if (!fbdev->buffer)
+		return -ENOMEM;
+
+	fbdev->cache = devm_kmalloc(dev, HT16K33_FB_SIZE, GFP_KERNEL);
+	if (!fbdev->cache) {
+		err = -ENOMEM;
+		goto err_fbdev_buffer;
+	}
+
+	fbdev->info = framebuffer_alloc(0, dev);
+	if (!fbdev->info) {
+		err = -ENOMEM;
+		goto err_fbdev_buffer;
+	}
+
+	err = device_property_read_u32(dev, "refresh-rate-hz",
+				       &fbdev->refresh_rate);
+	if (err) {
+		dev_err(dev, "refresh rate not specified\n");
+		goto err_fbdev_info;
+	}
+	fb_bl_default_curve(fbdev->info, 0, MIN_BRIGHTNESS, MAX_BRIGHTNESS);
+
+	INIT_DELAYED_WORK(&priv->work, ht16k33_fb_update);
+	fbdev->info->fbops = &ht16k33_fb_ops;
+	fbdev->info->screen_buffer = fbdev->buffer;
+	fbdev->info->screen_size = HT16K33_FB_SIZE;
+	fbdev->info->fix = ht16k33_fb_fix;
+	fbdev->info->var = ht16k33_fb_var;
+	fbdev->info->bl_dev = bl;
+	fbdev->info->pseudo_palette = NULL;
+	fbdev->info->par = priv;
+
+	err = register_framebuffer(fbdev->info);
+	if (err)
+		goto err_fbdev_info;
+
+	ht16k33_fb_queue(priv);
+	return 0;
+
+err_fbdev_info:
+	framebuffer_release(fbdev->info);
+err_fbdev_buffer:
+	free_page((unsigned long) fbdev->buffer);
+
+	return err;
+}
+
+static int ht16k33_seg_probe(struct device *dev, struct ht16k33_priv *priv,
+			     uint32_t brightness)
+{
+	struct ht16k33_seg *seg = &priv->seg;
+	int err;
+
+	err = ht16k33_brightness_set(priv, brightness);
+	if (err)
+		return err;
+
+	switch (priv->type) {
+	case DISP_MATRIX:
+		/* not handled here */
+		err = -EINVAL;
+		break;
+
+	case DISP_QUAD_7SEG:
+		INIT_DELAYED_WORK(&priv->work, ht16k33_seg7_update);
+		seg->map.seg7 = initial_map_seg7;
+		seg->map_size = sizeof(seg->map.seg7);
+		err = device_create_file(dev, &dev_attr_map_seg7);
+		break;
+
+	case DISP_QUAD_14SEG:
+		INIT_DELAYED_WORK(&priv->work, ht16k33_seg14_update);
+		seg->map.seg14 = initial_map_seg14;
+		seg->map_size = sizeof(seg->map.seg14);
+		err = device_create_file(dev, &dev_attr_map_seg14);
+		break;
+	}
+	if (err)
+		return err;
+
+	err = linedisp_register(&seg->linedisp, dev, 4, seg->curr,
+				ht16k33_linedisp_update);
+	if (err)
+		goto err_remove_map_file;
+
+	return 0;
+
+err_remove_map_file:
+	device_remove_file(dev, &dev_attr_map_seg7);
+	device_remove_file(dev, &dev_attr_map_seg14);
+	return err;
+}
+
+static int ht16k33_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	const struct of_device_id *id;
+	struct ht16k33_priv *priv;
+	uint32_t dft_brightness;
+	int err;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(dev, "i2c_check_functionality error\n");
+		return -EIO;
+	}
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->client = client;
+	id = i2c_of_match_device(dev->driver->of_match_table, client);
+	if (id)
+		priv->type = (uintptr_t)id->data;
+	i2c_set_clientdata(client, priv);
+
+	err = ht16k33_initialize(priv);
+	if (err)
+		return err;
+
+	err = device_property_read_u32(dev, "default-brightness-level",
+				       &dft_brightness);
+	if (err) {
+		dft_brightness = MAX_BRIGHTNESS;
+	} else if (dft_brightness > MAX_BRIGHTNESS) {
+		dev_warn(dev,
+			 "invalid default brightness level: %u, using %u\n",
+			 dft_brightness, MAX_BRIGHTNESS);
+		dft_brightness = MAX_BRIGHTNESS;
+	}
+
+	/* LED */
+	err = ht16k33_led_probe(dev, &priv->led, dft_brightness);
+	if (err)
+		return err;
+
+	/* Keypad */
+	if (client->irq > 0) {
+		err = ht16k33_keypad_probe(client, &priv->keypad);
+		if (err)
+			return err;
+	}
+
+	switch (priv->type) {
+	case DISP_MATRIX:
+		/* Frame Buffer Display */
+		err = ht16k33_fbdev_probe(dev, priv, dft_brightness);
+		break;
+
+	case DISP_QUAD_7SEG:
+	case DISP_QUAD_14SEG:
+		/* Segment Display */
+		err = ht16k33_seg_probe(dev, priv, dft_brightness);
+		break;
+	}
+	return err;
+}
+
+static void ht16k33_remove(struct i2c_client *client)
+{
+	struct ht16k33_priv *priv = i2c_get_clientdata(client);
+	struct ht16k33_fbdev *fbdev = &priv->fbdev;
+
+	cancel_delayed_work_sync(&priv->work);
+
+	switch (priv->type) {
+	case DISP_MATRIX:
+		unregister_framebuffer(fbdev->info);
+		framebuffer_release(fbdev->info);
+		free_page((unsigned long)fbdev->buffer);
+		break;
+
+	case DISP_QUAD_7SEG:
+	case DISP_QUAD_14SEG:
+		linedisp_unregister(&priv->seg.linedisp);
+		device_remove_file(&client->dev, &dev_attr_map_seg7);
+		device_remove_file(&client->dev, &dev_attr_map_seg14);
+		break;
+	}
+}
+
+static const struct i2c_device_id ht16k33_i2c_match[] = {
+	{ "ht16k33", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ht16k33_i2c_match);
+
+static const struct of_device_id ht16k33_of_match[] = {
+	{
+		/* 0.56" 4-Digit 7-Segment FeatherWing Display (Red) */
+		.compatible = "adafruit,3108", .data = (void *)DISP_QUAD_7SEG,
+	}, {
+		/* 0.54" Quad Alphanumeric FeatherWing Display (Red) */
+		.compatible = "adafruit,3130", .data = (void *)DISP_QUAD_14SEG,
+	}, {
+		/* Generic, assumed Dot-Matrix Display */
+		.compatible = "holtek,ht16k33", .data = (void *)DISP_MATRIX,
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ht16k33_of_match);
+
+static struct i2c_driver ht16k33_driver = {
+	.probe		= ht16k33_probe,
+	.remove		= ht16k33_remove,
+	.driver		= {
+		.name		= DRIVER_NAME,
+		.of_match_table	= ht16k33_of_match,
+	},
+	.id_table = ht16k33_i2c_match,
+};
+module_i2c_driver(ht16k33_driver);
+
+MODULE_DESCRIPTION("Holtek HT16K33 driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Robin van der Gracht <robin@protonic.nl>");
diff --git a/drivers/auxdisplay/img-ascii-lcd.c b/drivers/auxdisplay/img-ascii-lcd.c
new file mode 100644
index 000000000..fa23e415f
--- /dev/null
+++ b/drivers/auxdisplay/img-ascii-lcd.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Imagination Technologies
+ * Author: Paul Burton <paul.burton@mips.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "line-display.h"
+
+struct img_ascii_lcd_ctx;
+
+/**
+ * struct img_ascii_lcd_config - Configuration information about an LCD model
+ * @num_chars: the number of characters the LCD can display
+ * @external_regmap: true if registers are in a system controller, else false
+ * @update: function called to update the LCD
+ */
+struct img_ascii_lcd_config {
+	unsigned int num_chars;
+	bool external_regmap;
+	void (*update)(struct linedisp *linedisp);
+};
+
+/**
+ * struct img_ascii_lcd_ctx - Private data structure
+ * @base: the base address of the LCD registers
+ * @regmap: the regmap through which LCD registers are accessed
+ * @offset: the offset within regmap to the start of the LCD registers
+ * @cfg: pointer to the LCD model configuration
+ * @linedisp: line display structure
+ * @curr: the string currently displayed on the LCD
+ */
+struct img_ascii_lcd_ctx {
+	union {
+		void __iomem *base;
+		struct regmap *regmap;
+	};
+	u32 offset;
+	const struct img_ascii_lcd_config *cfg;
+	struct linedisp linedisp;
+	char curr[] __aligned(8);
+};
+
+/*
+ * MIPS Boston development board
+ */
+
+static void boston_update(struct linedisp *linedisp)
+{
+	struct img_ascii_lcd_ctx *ctx =
+		container_of(linedisp, struct img_ascii_lcd_ctx, linedisp);
+	ulong val;
+
+#if BITS_PER_LONG == 64
+	val = *((u64 *)&ctx->curr[0]);
+	__raw_writeq(val, ctx->base);
+#elif BITS_PER_LONG == 32
+	val = *((u32 *)&ctx->curr[0]);
+	__raw_writel(val, ctx->base);
+	val = *((u32 *)&ctx->curr[4]);
+	__raw_writel(val, ctx->base + 4);
+#else
+# error Not 32 or 64 bit
+#endif
+}
+
+static struct img_ascii_lcd_config boston_config = {
+	.num_chars = 8,
+	.update = boston_update,
+};
+
+/*
+ * MIPS Malta development board
+ */
+
+static void malta_update(struct linedisp *linedisp)
+{
+	struct img_ascii_lcd_ctx *ctx =
+		container_of(linedisp, struct img_ascii_lcd_ctx, linedisp);
+	unsigned int i;
+	int err = 0;
+
+	for (i = 0; i < linedisp->num_chars; i++) {
+		err = regmap_write(ctx->regmap,
+				   ctx->offset + (i * 8), ctx->curr[i]);
+		if (err)
+			break;
+	}
+
+	if (unlikely(err))
+		pr_err_ratelimited("Failed to update LCD display: %d\n", err);
+}
+
+static struct img_ascii_lcd_config malta_config = {
+	.num_chars = 8,
+	.external_regmap = true,
+	.update = malta_update,
+};
+
+/*
+ * MIPS SEAD3 development board
+ */
+
+enum {
+	SEAD3_REG_LCD_CTRL		= 0x00,
+#define SEAD3_REG_LCD_CTRL_SETDRAM	BIT(7)
+	SEAD3_REG_LCD_DATA		= 0x08,
+	SEAD3_REG_CPLD_STATUS		= 0x10,
+#define SEAD3_REG_CPLD_STATUS_BUSY	BIT(0)
+	SEAD3_REG_CPLD_DATA		= 0x18,
+#define SEAD3_REG_CPLD_DATA_BUSY	BIT(7)
+};
+
+static int sead3_wait_sm_idle(struct img_ascii_lcd_ctx *ctx)
+{
+	unsigned int status;
+	int err;
+
+	do {
+		err = regmap_read(ctx->regmap,
+				  ctx->offset + SEAD3_REG_CPLD_STATUS,
+				  &status);
+		if (err)
+			return err;
+	} while (status & SEAD3_REG_CPLD_STATUS_BUSY);
+
+	return 0;
+
+}
+
+static int sead3_wait_lcd_idle(struct img_ascii_lcd_ctx *ctx)
+{
+	unsigned int cpld_data;
+	int err;
+
+	err = sead3_wait_sm_idle(ctx);
+	if (err)
+		return err;
+
+	do {
+		err = regmap_read(ctx->regmap,
+				  ctx->offset + SEAD3_REG_LCD_CTRL,
+				  &cpld_data);
+		if (err)
+			return err;
+
+		err = sead3_wait_sm_idle(ctx);
+		if (err)
+			return err;
+
+		err = regmap_read(ctx->regmap,
+				  ctx->offset + SEAD3_REG_CPLD_DATA,
+				  &cpld_data);
+		if (err)
+			return err;
+	} while (cpld_data & SEAD3_REG_CPLD_DATA_BUSY);
+
+	return 0;
+}
+
+static void sead3_update(struct linedisp *linedisp)
+{
+	struct img_ascii_lcd_ctx *ctx =
+		container_of(linedisp, struct img_ascii_lcd_ctx, linedisp);
+	unsigned int i;
+	int err = 0;
+
+	for (i = 0; i < linedisp->num_chars; i++) {
+		err = sead3_wait_lcd_idle(ctx);
+		if (err)
+			break;
+
+		err = regmap_write(ctx->regmap,
+				   ctx->offset + SEAD3_REG_LCD_CTRL,
+				   SEAD3_REG_LCD_CTRL_SETDRAM | i);
+		if (err)
+			break;
+
+		err = sead3_wait_lcd_idle(ctx);
+		if (err)
+			break;
+
+		err = regmap_write(ctx->regmap,
+				   ctx->offset + SEAD3_REG_LCD_DATA,
+				   ctx->curr[i]);
+		if (err)
+			break;
+	}
+
+	if (unlikely(err))
+		pr_err_ratelimited("Failed to update LCD display: %d\n", err);
+}
+
+static struct img_ascii_lcd_config sead3_config = {
+	.num_chars = 16,
+	.external_regmap = true,
+	.update = sead3_update,
+};
+
+static const struct of_device_id img_ascii_lcd_matches[] = {
+	{ .compatible = "img,boston-lcd", .data = &boston_config },
+	{ .compatible = "mti,malta-lcd", .data = &malta_config },
+	{ .compatible = "mti,sead3-lcd", .data = &sead3_config },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, img_ascii_lcd_matches);
+
+/**
+ * img_ascii_lcd_probe() - probe an LCD display device
+ * @pdev: the LCD platform device
+ *
+ * Probe an LCD display device, ensuring that we have the required resources in
+ * order to access the LCD & setting up private data as well as sysfs files.
+ *
+ * Return: 0 on success, else -ERRNO
+ */
+static int img_ascii_lcd_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	const struct img_ascii_lcd_config *cfg;
+	struct device *dev = &pdev->dev;
+	struct img_ascii_lcd_ctx *ctx;
+	int err;
+
+	match = of_match_device(img_ascii_lcd_matches, dev);
+	if (!match)
+		return -ENODEV;
+
+	cfg = match->data;
+	ctx = devm_kzalloc(dev, sizeof(*ctx) + cfg->num_chars, GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	if (cfg->external_regmap) {
+		ctx->regmap = syscon_node_to_regmap(dev->parent->of_node);
+		if (IS_ERR(ctx->regmap))
+			return PTR_ERR(ctx->regmap);
+
+		if (of_property_read_u32(dev->of_node, "offset", &ctx->offset))
+			return -EINVAL;
+	} else {
+		ctx->base = devm_platform_ioremap_resource(pdev, 0);
+		if (IS_ERR(ctx->base))
+			return PTR_ERR(ctx->base);
+	}
+
+	err = linedisp_register(&ctx->linedisp, dev, cfg->num_chars, ctx->curr,
+				cfg->update);
+	if (err)
+		return err;
+
+	/* for backwards compatibility */
+	err = compat_only_sysfs_link_entry_to_kobj(&dev->kobj,
+						   &ctx->linedisp.dev.kobj,
+						   "message", NULL);
+	if (err)
+		goto err_unregister;
+
+	platform_set_drvdata(pdev, ctx);
+	return 0;
+
+err_unregister:
+	linedisp_unregister(&ctx->linedisp);
+	return err;
+}
+
+/**
+ * img_ascii_lcd_remove() - remove an LCD display device
+ * @pdev: the LCD platform device
+ *
+ * Remove an LCD display device, freeing private resources & ensuring that the
+ * driver stops using the LCD display registers.
+ *
+ * Return: 0
+ */
+static int img_ascii_lcd_remove(struct platform_device *pdev)
+{
+	struct img_ascii_lcd_ctx *ctx = platform_get_drvdata(pdev);
+
+	sysfs_remove_link(&pdev->dev.kobj, "message");
+	linedisp_unregister(&ctx->linedisp);
+	return 0;
+}
+
+static struct platform_driver img_ascii_lcd_driver = {
+	.driver = {
+		.name		= "img-ascii-lcd",
+		.of_match_table	= img_ascii_lcd_matches,
+	},
+	.probe	= img_ascii_lcd_probe,
+	.remove	= img_ascii_lcd_remove,
+};
+module_platform_driver(img_ascii_lcd_driver);
+
+MODULE_DESCRIPTION("Imagination Technologies ASCII LCD Display");
+MODULE_AUTHOR("Paul Burton <paul.burton@mips.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/auxdisplay/ks0108.c b/drivers/auxdisplay/ks0108.c
new file mode 100644
index 000000000..234f9dbe6
--- /dev/null
+++ b/drivers/auxdisplay/ks0108.c
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *    Filename: ks0108.c
+ *     Version: 0.1.0
+ * Description: ks0108 LCD Controller driver
+ *     Depends: parport
+ *
+ *      Author: Copyright (C) Miguel Ojeda <ojeda@kernel.org>
+ *        Date: 2006-10-31
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/parport.h>
+#include <linux/ks0108.h>
+
+#define KS0108_NAME "ks0108"
+
+/*
+ * Module Parameters
+ */
+
+static unsigned int ks0108_port = CONFIG_KS0108_PORT;
+module_param(ks0108_port, uint, 0444);
+MODULE_PARM_DESC(ks0108_port, "Parallel port where the LCD is connected");
+
+static unsigned int ks0108_delay = CONFIG_KS0108_DELAY;
+module_param(ks0108_delay, uint, 0444);
+MODULE_PARM_DESC(ks0108_delay, "Delay between each control writing (microseconds)");
+
+/*
+ * Device
+ */
+
+static struct parport *ks0108_parport;
+static struct pardevice *ks0108_pardevice;
+
+/*
+ * ks0108 Exported Commands (don't lock)
+ *
+ *   You _should_ lock in the top driver: This functions _should not_
+ *   get race conditions in any way. Locking for each byte here would be
+ *   so slow and useless.
+ *
+ *   There are not bit definitions because they are not flags,
+ *   just arbitrary combinations defined by the documentation for each
+ *   function in the ks0108 LCD controller. If you want to know what means
+ *   a specific combination, look at the function's name.
+ *
+ *   The ks0108_writecontrol bits need to be reverted ^(0,1,3) because
+ *   the parallel port also revert them using a "not" logic gate.
+ */
+
+#define bit(n) (((unsigned char)1)<<(n))
+
+void ks0108_writedata(unsigned char byte)
+{
+	parport_write_data(ks0108_parport, byte);
+}
+
+void ks0108_writecontrol(unsigned char byte)
+{
+	udelay(ks0108_delay);
+	parport_write_control(ks0108_parport, byte ^ (bit(0) | bit(1) | bit(3)));
+}
+
+void ks0108_displaystate(unsigned char state)
+{
+	ks0108_writedata((state ? bit(0) : 0) | bit(1) | bit(2) | bit(3) | bit(4) | bit(5));
+}
+
+void ks0108_startline(unsigned char startline)
+{
+	ks0108_writedata(min_t(unsigned char, startline, 63) | bit(6) |
+			 bit(7));
+}
+
+void ks0108_address(unsigned char address)
+{
+	ks0108_writedata(min_t(unsigned char, address, 63) | bit(6));
+}
+
+void ks0108_page(unsigned char page)
+{
+	ks0108_writedata(min_t(unsigned char, page, 7) | bit(3) | bit(4) |
+			 bit(5) | bit(7));
+}
+
+EXPORT_SYMBOL_GPL(ks0108_writedata);
+EXPORT_SYMBOL_GPL(ks0108_writecontrol);
+EXPORT_SYMBOL_GPL(ks0108_displaystate);
+EXPORT_SYMBOL_GPL(ks0108_startline);
+EXPORT_SYMBOL_GPL(ks0108_address);
+EXPORT_SYMBOL_GPL(ks0108_page);
+
+/*
+ * Is the module inited?
+ */
+
+static unsigned char ks0108_inited;
+unsigned char ks0108_isinited(void)
+{
+	return ks0108_inited;
+}
+EXPORT_SYMBOL_GPL(ks0108_isinited);
+
+static void ks0108_parport_attach(struct parport *port)
+{
+	struct pardev_cb ks0108_cb;
+
+	if (port->base != ks0108_port)
+		return;
+
+	memset(&ks0108_cb, 0, sizeof(ks0108_cb));
+	ks0108_cb.flags = PARPORT_DEV_EXCL;
+	ks0108_pardevice = parport_register_dev_model(port, KS0108_NAME,
+						      &ks0108_cb, 0);
+	if (!ks0108_pardevice) {
+		pr_err("ERROR: parport didn't register new device\n");
+		return;
+	}
+	if (parport_claim(ks0108_pardevice)) {
+		pr_err("could not claim access to parport %i. Aborting.\n",
+		       ks0108_port);
+		goto err_unreg_device;
+	}
+
+	ks0108_parport = port;
+	ks0108_inited = 1;
+	return;
+
+err_unreg_device:
+	parport_unregister_device(ks0108_pardevice);
+	ks0108_pardevice = NULL;
+}
+
+static void ks0108_parport_detach(struct parport *port)
+{
+	if (port->base != ks0108_port)
+		return;
+
+	if (!ks0108_pardevice) {
+		pr_err("%s: already unregistered.\n", KS0108_NAME);
+		return;
+	}
+
+	parport_release(ks0108_pardevice);
+	parport_unregister_device(ks0108_pardevice);
+	ks0108_pardevice = NULL;
+	ks0108_parport = NULL;
+}
+
+/*
+ * Module Init & Exit
+ */
+
+static struct parport_driver ks0108_parport_driver = {
+	.name = "ks0108",
+	.match_port = ks0108_parport_attach,
+	.detach = ks0108_parport_detach,
+	.devmodel = true,
+};
+module_parport_driver(ks0108_parport_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Miguel Ojeda <ojeda@kernel.org>");
+MODULE_DESCRIPTION("ks0108 LCD Controller driver");
+
diff --git a/drivers/auxdisplay/lcd2s.c b/drivers/auxdisplay/lcd2s.c
new file mode 100644
index 000000000..6422be0df
--- /dev/null
+++ b/drivers/auxdisplay/lcd2s.c
@@ -0,0 +1,376 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Console driver for LCD2S 4x20 character displays connected through i2c.
+ *  The display also has a SPI interface, but the driver does not support
+ *  this yet.
+ *
+ *  This is a driver allowing you to use a LCD2S 4x20 from Modtronix
+ *  engineering as auxdisplay character device.
+ *
+ *  (C) 2019 by Lemonage Software GmbH
+ *  Author: Lars Pöschel <poeschel@lemonage.de>
+ *  All rights reserved.
+ */
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+
+#include "charlcd.h"
+
+#define LCD2S_CMD_CUR_MOVES_FWD		0x09
+#define LCD2S_CMD_CUR_BLINK_OFF		0x10
+#define LCD2S_CMD_CUR_UL_OFF		0x11
+#define LCD2S_CMD_DISPLAY_OFF		0x12
+#define LCD2S_CMD_CUR_BLINK_ON		0x18
+#define LCD2S_CMD_CUR_UL_ON		0x19
+#define LCD2S_CMD_DISPLAY_ON		0x1a
+#define LCD2S_CMD_BACKLIGHT_OFF		0x20
+#define LCD2S_CMD_BACKLIGHT_ON		0x28
+#define LCD2S_CMD_WRITE			0x80
+#define LCD2S_CMD_MOV_CUR_RIGHT		0x83
+#define LCD2S_CMD_MOV_CUR_LEFT		0x84
+#define LCD2S_CMD_SHIFT_RIGHT		0x85
+#define LCD2S_CMD_SHIFT_LEFT		0x86
+#define LCD2S_CMD_SHIFT_UP		0x87
+#define LCD2S_CMD_SHIFT_DOWN		0x88
+#define LCD2S_CMD_CUR_ADDR		0x89
+#define LCD2S_CMD_CUR_POS		0x8a
+#define LCD2S_CMD_CUR_RESET		0x8b
+#define LCD2S_CMD_CLEAR			0x8c
+#define LCD2S_CMD_DEF_CUSTOM_CHAR	0x92
+#define LCD2S_CMD_READ_STATUS		0xd0
+
+#define LCD2S_CHARACTER_SIZE		8
+
+#define LCD2S_STATUS_BUF_MASK		0x7f
+
+struct lcd2s_data {
+	struct i2c_client *i2c;
+	struct charlcd *charlcd;
+};
+
+static s32 lcd2s_wait_buf_free(const struct i2c_client *client, int count)
+{
+	s32 status;
+
+	status = i2c_smbus_read_byte_data(client, LCD2S_CMD_READ_STATUS);
+	if (status < 0)
+		return status;
+
+	while ((status & LCD2S_STATUS_BUF_MASK) < count) {
+		mdelay(1);
+		status = i2c_smbus_read_byte_data(client,
+						  LCD2S_CMD_READ_STATUS);
+		if (status < 0)
+			return status;
+	}
+	return 0;
+}
+
+static int lcd2s_i2c_master_send(const struct i2c_client *client,
+				 const char *buf, int count)
+{
+	s32 status;
+
+	status = lcd2s_wait_buf_free(client, count);
+	if (status < 0)
+		return status;
+
+	return i2c_master_send(client, buf, count);
+}
+
+static int lcd2s_i2c_smbus_write_byte(const struct i2c_client *client, u8 value)
+{
+	s32 status;
+
+	status = lcd2s_wait_buf_free(client, 1);
+	if (status < 0)
+		return status;
+
+	return i2c_smbus_write_byte(client, value);
+}
+
+static int lcd2s_print(struct charlcd *lcd, int c)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+	u8 buf[2] = { LCD2S_CMD_WRITE, c };
+
+	lcd2s_i2c_master_send(lcd2s->i2c, buf, sizeof(buf));
+	return 0;
+}
+
+static int lcd2s_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+	u8 buf[3] = { LCD2S_CMD_CUR_POS, y + 1, x + 1 };
+
+	lcd2s_i2c_master_send(lcd2s->i2c, buf, sizeof(buf));
+
+	return 0;
+}
+
+static int lcd2s_home(struct charlcd *lcd)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_RESET);
+	return 0;
+}
+
+static int lcd2s_init_display(struct charlcd *lcd)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	/* turn everything off, but display on */
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_DISPLAY_ON);
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_BACKLIGHT_OFF);
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_MOVES_FWD);
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_BLINK_OFF);
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_UL_OFF);
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CLEAR);
+
+	return 0;
+}
+
+static int lcd2s_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	if (dir == CHARLCD_SHIFT_LEFT)
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_MOV_CUR_LEFT);
+	else
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_MOV_CUR_RIGHT);
+
+	return 0;
+}
+
+static int lcd2s_shift_display(struct charlcd *lcd, enum charlcd_shift_dir dir)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	if (dir == CHARLCD_SHIFT_LEFT)
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_SHIFT_LEFT);
+	else
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_SHIFT_RIGHT);
+
+	return 0;
+}
+
+static void lcd2s_backlight(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	if (on)
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_BACKLIGHT_ON);
+	else
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_BACKLIGHT_OFF);
+}
+
+static int lcd2s_display(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	if (on)
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_DISPLAY_ON);
+	else
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_DISPLAY_OFF);
+
+	return 0;
+}
+
+static int lcd2s_cursor(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	if (on)
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_UL_ON);
+	else
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_UL_OFF);
+
+	return 0;
+}
+
+static int lcd2s_blink(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	if (on)
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_BLINK_ON);
+	else
+		lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CUR_BLINK_OFF);
+
+	return 0;
+}
+
+static int lcd2s_fontsize(struct charlcd *lcd, enum charlcd_fontsize size)
+{
+	return 0;
+}
+
+static int lcd2s_lines(struct charlcd *lcd, enum charlcd_lines lines)
+{
+	return 0;
+}
+
+/*
+ * Generator: LGcxxxxx...xx; must have <c> between '0' and '7',
+ * representing the numerical ASCII code of the redefined character,
+ * and <xx...xx> a sequence of 16 hex digits representing 8 bytes
+ * for each character. Most LCDs will only use 5 lower bits of
+ * the 7 first bytes.
+ */
+static int lcd2s_redefine_char(struct charlcd *lcd, char *esc)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+	u8 buf[LCD2S_CHARACTER_SIZE + 2] = { LCD2S_CMD_DEF_CUSTOM_CHAR };
+	u8 value;
+	int shift, i;
+
+	if (!strchr(esc, ';'))
+		return 0;
+
+	esc++;
+
+	buf[1] = *(esc++) - '0';
+	if (buf[1] > 7)
+		return 1;
+
+	i = 2;
+	shift = 0;
+	value = 0;
+	while (*esc && i < LCD2S_CHARACTER_SIZE + 2) {
+		int half;
+
+		shift ^= 4;
+		half = hex_to_bin(*esc++);
+		if (half < 0)
+			continue;
+
+		value |= half << shift;
+		if (shift == 0) {
+			buf[i++] = value;
+			value = 0;
+		}
+	}
+
+	lcd2s_i2c_master_send(lcd2s->i2c, buf, sizeof(buf));
+	return 1;
+}
+
+static int lcd2s_clear_display(struct charlcd *lcd)
+{
+	struct lcd2s_data *lcd2s = lcd->drvdata;
+
+	/* This implicitly sets cursor to first row and column */
+	lcd2s_i2c_smbus_write_byte(lcd2s->i2c, LCD2S_CMD_CLEAR);
+	return 0;
+}
+
+static const struct charlcd_ops lcd2s_ops = {
+	.print		= lcd2s_print,
+	.backlight	= lcd2s_backlight,
+	.gotoxy		= lcd2s_gotoxy,
+	.home		= lcd2s_home,
+	.clear_display	= lcd2s_clear_display,
+	.init_display	= lcd2s_init_display,
+	.shift_cursor	= lcd2s_shift_cursor,
+	.shift_display	= lcd2s_shift_display,
+	.display	= lcd2s_display,
+	.cursor		= lcd2s_cursor,
+	.blink		= lcd2s_blink,
+	.fontsize	= lcd2s_fontsize,
+	.lines		= lcd2s_lines,
+	.redefine_char	= lcd2s_redefine_char,
+};
+
+static int lcd2s_i2c_probe(struct i2c_client *i2c)
+{
+	struct charlcd *lcd;
+	struct lcd2s_data *lcd2s;
+	int err;
+
+	if (!i2c_check_functionality(i2c->adapter,
+			I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
+			I2C_FUNC_SMBUS_WRITE_BLOCK_DATA))
+		return -EIO;
+
+	lcd2s = devm_kzalloc(&i2c->dev, sizeof(*lcd2s), GFP_KERNEL);
+	if (!lcd2s)
+		return -ENOMEM;
+
+	/* Test, if the display is responding */
+	err = lcd2s_i2c_smbus_write_byte(i2c, LCD2S_CMD_DISPLAY_OFF);
+	if (err < 0)
+		return err;
+
+	lcd = charlcd_alloc();
+	if (!lcd)
+		return -ENOMEM;
+
+	lcd->drvdata = lcd2s;
+	lcd2s->i2c = i2c;
+	lcd2s->charlcd = lcd;
+
+	/* Required properties */
+	err = device_property_read_u32(&i2c->dev, "display-height-chars",
+			&lcd->height);
+	if (err)
+		goto fail1;
+
+	err = device_property_read_u32(&i2c->dev, "display-width-chars",
+			&lcd->width);
+	if (err)
+		goto fail1;
+
+	lcd->ops = &lcd2s_ops;
+
+	err = charlcd_register(lcd2s->charlcd);
+	if (err)
+		goto fail1;
+
+	i2c_set_clientdata(i2c, lcd2s);
+	return 0;
+
+fail1:
+	charlcd_free(lcd2s->charlcd);
+	return err;
+}
+
+static void lcd2s_i2c_remove(struct i2c_client *i2c)
+{
+	struct lcd2s_data *lcd2s = i2c_get_clientdata(i2c);
+
+	charlcd_unregister(lcd2s->charlcd);
+	charlcd_free(lcd2s->charlcd);
+}
+
+static const struct i2c_device_id lcd2s_i2c_id[] = {
+	{ "lcd2s", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, lcd2s_i2c_id);
+
+static const struct of_device_id lcd2s_of_table[] = {
+	{ .compatible = "modtronix,lcd2s" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, lcd2s_of_table);
+
+static struct i2c_driver lcd2s_i2c_driver = {
+	.driver = {
+		.name = "lcd2s",
+		.of_match_table = lcd2s_of_table,
+	},
+	.probe = lcd2s_i2c_probe,
+	.remove = lcd2s_i2c_remove,
+	.id_table = lcd2s_i2c_id,
+};
+module_i2c_driver(lcd2s_i2c_driver);
+
+MODULE_DESCRIPTION("LCD2S character display driver");
+MODULE_AUTHOR("Lars Poeschel");
+MODULE_LICENSE("GPL");
diff --git a/drivers/auxdisplay/line-display.c b/drivers/auxdisplay/line-display.c
new file mode 100644
index 000000000..03e7f104a
--- /dev/null
+++ b/drivers/auxdisplay/line-display.c
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Character line display core support
+ *
+ * Copyright (C) 2016 Imagination Technologies
+ * Author: Paul Burton <paul.burton@mips.com>
+ *
+ * Copyright (C) 2021 Glider bv
+ */
+
+#include <generated/utsrelease.h>
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/timer.h>
+
+#include "line-display.h"
+
+#define DEFAULT_SCROLL_RATE	(HZ / 2)
+
+/**
+ * linedisp_scroll() - scroll the display by a character
+ * @t: really a pointer to the private data structure
+ *
+ * Scroll the current message along the display by one character, rearming the
+ * timer if required.
+ */
+static void linedisp_scroll(struct timer_list *t)
+{
+	struct linedisp *linedisp = from_timer(linedisp, t, timer);
+	unsigned int i, ch = linedisp->scroll_pos;
+	unsigned int num_chars = linedisp->num_chars;
+
+	/* update the current message string */
+	for (i = 0; i < num_chars;) {
+		/* copy as many characters from the string as possible */
+		for (; i < num_chars && ch < linedisp->message_len; i++, ch++)
+			linedisp->buf[i] = linedisp->message[ch];
+
+		/* wrap around to the start of the string */
+		ch = 0;
+	}
+
+	/* update the display */
+	linedisp->update(linedisp);
+
+	/* move on to the next character */
+	linedisp->scroll_pos++;
+	linedisp->scroll_pos %= linedisp->message_len;
+
+	/* rearm the timer */
+	if (linedisp->message_len > num_chars && linedisp->scroll_rate)
+		mod_timer(&linedisp->timer, jiffies + linedisp->scroll_rate);
+}
+
+/**
+ * linedisp_display() - set the message to be displayed
+ * @linedisp: pointer to the private data structure
+ * @msg: the message to display
+ * @count: length of msg, or -1
+ *
+ * Display a new message @msg on the display. @msg can be longer than the
+ * number of characters the display can display, in which case it will begin
+ * scrolling across the display.
+ *
+ * Return: 0 on success, -ENOMEM on memory allocation failure
+ */
+static int linedisp_display(struct linedisp *linedisp, const char *msg,
+			    ssize_t count)
+{
+	char *new_msg;
+
+	/* stop the scroll timer */
+	del_timer_sync(&linedisp->timer);
+
+	if (count == -1)
+		count = strlen(msg);
+
+	/* if the string ends with a newline, trim it */
+	if (msg[count - 1] == '\n')
+		count--;
+
+	if (!count) {
+		/* Clear the display */
+		kfree(linedisp->message);
+		linedisp->message = NULL;
+		linedisp->message_len = 0;
+		memset(linedisp->buf, ' ', linedisp->num_chars);
+		linedisp->update(linedisp);
+		return 0;
+	}
+
+	new_msg = kmemdup_nul(msg, count, GFP_KERNEL);
+	if (!new_msg)
+		return -ENOMEM;
+
+	kfree(linedisp->message);
+
+	linedisp->message = new_msg;
+	linedisp->message_len = count;
+	linedisp->scroll_pos = 0;
+
+	/* update the display */
+	linedisp_scroll(&linedisp->timer);
+
+	return 0;
+}
+
+/**
+ * message_show() - read message via sysfs
+ * @dev: the display device
+ * @attr: the display message attribute
+ * @buf: the buffer to read the message into
+ *
+ * Read the current message being displayed or scrolled across the display into
+ * @buf, for reads from sysfs.
+ *
+ * Return: the number of characters written to @buf
+ */
+static ssize_t message_show(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	struct linedisp *linedisp = container_of(dev, struct linedisp, dev);
+
+	return sysfs_emit(buf, "%s\n", linedisp->message);
+}
+
+/**
+ * message_store() - write a new message via sysfs
+ * @dev: the display device
+ * @attr: the display message attribute
+ * @buf: the buffer containing the new message
+ * @count: the size of the message in @buf
+ *
+ * Write a new message to display or scroll across the display from sysfs.
+ *
+ * Return: the size of the message on success, else -ERRNO
+ */
+static ssize_t message_store(struct device *dev, struct device_attribute *attr,
+			     const char *buf, size_t count)
+{
+	struct linedisp *linedisp = container_of(dev, struct linedisp, dev);
+	int err;
+
+	err = linedisp_display(linedisp, buf, count);
+	return err ?: count;
+}
+
+static DEVICE_ATTR_RW(message);
+
+static ssize_t scroll_step_ms_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct linedisp *linedisp = container_of(dev, struct linedisp, dev);
+
+	return sysfs_emit(buf, "%u\n", jiffies_to_msecs(linedisp->scroll_rate));
+}
+
+static ssize_t scroll_step_ms_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	struct linedisp *linedisp = container_of(dev, struct linedisp, dev);
+	unsigned int ms;
+
+	if (kstrtouint(buf, 10, &ms) != 0)
+		return -EINVAL;
+
+	linedisp->scroll_rate = msecs_to_jiffies(ms);
+	if (linedisp->message && linedisp->message_len > linedisp->num_chars) {
+		del_timer_sync(&linedisp->timer);
+		if (linedisp->scroll_rate)
+			linedisp_scroll(&linedisp->timer);
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR_RW(scroll_step_ms);
+
+static struct attribute *linedisp_attrs[] = {
+	&dev_attr_message.attr,
+	&dev_attr_scroll_step_ms.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(linedisp);
+
+static const struct device_type linedisp_type = {
+	.groups	= linedisp_groups,
+};
+
+/**
+ * linedisp_register - register a character line display
+ * @linedisp: pointer to character line display structure
+ * @parent: parent device
+ * @num_chars: the number of characters that can be displayed
+ * @buf: pointer to a buffer that can hold @num_chars characters
+ * @update: Function called to update the display.  This must not sleep!
+ *
+ * Return: zero on success, else a negative error code.
+ */
+int linedisp_register(struct linedisp *linedisp, struct device *parent,
+		      unsigned int num_chars, char *buf,
+		      void (*update)(struct linedisp *linedisp))
+{
+	static atomic_t linedisp_id = ATOMIC_INIT(-1);
+	int err;
+
+	memset(linedisp, 0, sizeof(*linedisp));
+	linedisp->dev.parent = parent;
+	linedisp->dev.type = &linedisp_type;
+	linedisp->update = update;
+	linedisp->buf = buf;
+	linedisp->num_chars = num_chars;
+	linedisp->scroll_rate = DEFAULT_SCROLL_RATE;
+
+	device_initialize(&linedisp->dev);
+	dev_set_name(&linedisp->dev, "linedisp.%lu",
+		     (unsigned long)atomic_inc_return(&linedisp_id));
+
+	/* initialise a timer for scrolling the message */
+	timer_setup(&linedisp->timer, linedisp_scroll, 0);
+
+	err = device_add(&linedisp->dev);
+	if (err)
+		goto out_del_timer;
+
+	/* display a default message */
+	err = linedisp_display(linedisp, "Linux " UTS_RELEASE "       ", -1);
+	if (err)
+		goto out_del_dev;
+
+	return 0;
+
+out_del_dev:
+	device_del(&linedisp->dev);
+out_del_timer:
+	del_timer_sync(&linedisp->timer);
+	put_device(&linedisp->dev);
+	return err;
+}
+EXPORT_SYMBOL_GPL(linedisp_register);
+
+/**
+ * linedisp_unregister - unregister a character line display
+ * @linedisp: pointer to character line display structure registered previously
+ *	      with linedisp_register()
+ */
+void linedisp_unregister(struct linedisp *linedisp)
+{
+	device_del(&linedisp->dev);
+	del_timer_sync(&linedisp->timer);
+	kfree(linedisp->message);
+	put_device(&linedisp->dev);
+}
+EXPORT_SYMBOL_GPL(linedisp_unregister);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/auxdisplay/line-display.h b/drivers/auxdisplay/line-display.h
new file mode 100644
index 000000000..0f5891d34
--- /dev/null
+++ b/drivers/auxdisplay/line-display.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Character line display core support
+ *
+ * Copyright (C) 2016 Imagination Technologies
+ * Author: Paul Burton <paul.burton@mips.com>
+ *
+ * Copyright (C) 2021 Glider bv
+ */
+
+#ifndef _LINEDISP_H
+#define _LINEDISP_H
+
+/**
+ * struct linedisp - character line display private data structure
+ * @dev: the line display device
+ * @timer: timer used to implement scrolling
+ * @update: function called to update the display
+ * @buf: pointer to the buffer for the string currently displayed
+ * @message: the full message to display or scroll on the display
+ * @num_chars: the number of characters that can be displayed
+ * @message_len: the length of the @message string
+ * @scroll_pos: index of the first character of @message currently displayed
+ * @scroll_rate: scroll interval in jiffies
+ */
+struct linedisp {
+	struct device dev;
+	struct timer_list timer;
+	void (*update)(struct linedisp *linedisp);
+	char *buf;
+	char *message;
+	unsigned int num_chars;
+	unsigned int message_len;
+	unsigned int scroll_pos;
+	unsigned int scroll_rate;
+};
+
+int linedisp_register(struct linedisp *linedisp, struct device *parent,
+		      unsigned int num_chars, char *buf,
+		      void (*update)(struct linedisp *linedisp));
+void linedisp_unregister(struct linedisp *linedisp);
+
+#endif /* LINEDISP_H */
diff --git a/drivers/auxdisplay/panel.c b/drivers/auxdisplay/panel.c
new file mode 100644
index 000000000..eba04c0de
--- /dev/null
+++ b/drivers/auxdisplay/panel.c
@@ -0,0 +1,1739 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Front panel driver for Linux
+ * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
+ * Copyright (C) 2016-2017 Glider bvba
+ *
+ * This code drives an LCD module (/dev/lcd), and a keypad (/dev/keypad)
+ * connected to a parallel printer port.
+ *
+ * The LCD module may either be an HD44780-like 8-bit parallel LCD, or a 1-bit
+ * serial module compatible with Samsung's KS0074. The pins may be connected in
+ * any combination, everything is programmable.
+ *
+ * The keypad consists in a matrix of push buttons connecting input pins to
+ * data output pins or to the ground. The combinations have to be hard-coded
+ * in the driver, though several profiles exist and adding new ones is easy.
+ *
+ * Several profiles are provided for commonly found LCD+keypad modules on the
+ * market, such as those found in Nexcom's appliances.
+ *
+ * FIXME:
+ *      - the initialization/deinitialization process is very dirty and should
+ *        be rewritten. It may even be buggy.
+ *
+ * TODO:
+ *	- document 24 keys keyboard (3 rows of 8 cols, 32 diodes + 2 inputs)
+ *      - make the LCD a part of a virtual screen of Vx*Vy
+ *	- make the inputs list smp-safe
+ *      - change the keyboard to a double mapping : signals -> key_id -> values
+ *        so that applications can change values without knowing signals
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/miscdevice.h>
+#include <linux/slab.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/parport.h>
+#include <linux/list.h>
+
+#include <linux/io.h>
+#include <linux/uaccess.h>
+
+#include "charlcd.h"
+#include "hd44780_common.h"
+
+#define LCD_MAXBYTES		256	/* max burst write */
+
+#define KEYPAD_BUFFER		64
+
+/* poll the keyboard this every second */
+#define INPUT_POLL_TIME		(HZ / 50)
+/* a key starts to repeat after this times INPUT_POLL_TIME */
+#define KEYPAD_REP_START	(10)
+/* a key repeats this times INPUT_POLL_TIME */
+#define KEYPAD_REP_DELAY	(2)
+
+/* converts an r_str() input to an active high, bits string : 000BAOSE */
+#define PNL_PINPUT(a)		((((unsigned char)(a)) ^ 0x7F) >> 3)
+
+#define PNL_PBUSY		0x80	/* inverted input, active low */
+#define PNL_PACK		0x40	/* direct input, active low */
+#define PNL_POUTPA		0x20	/* direct input, active high */
+#define PNL_PSELECD		0x10	/* direct input, active high */
+#define PNL_PERRORP		0x08	/* direct input, active low */
+
+#define PNL_PBIDIR		0x20	/* bi-directional ports */
+/* high to read data in or-ed with data out */
+#define PNL_PINTEN		0x10
+#define PNL_PSELECP		0x08	/* inverted output, active low */
+#define PNL_PINITP		0x04	/* direct output, active low */
+#define PNL_PAUTOLF		0x02	/* inverted output, active low */
+#define PNL_PSTROBE		0x01	/* inverted output */
+
+#define PNL_PD0			0x01
+#define PNL_PD1			0x02
+#define PNL_PD2			0x04
+#define PNL_PD3			0x08
+#define PNL_PD4			0x10
+#define PNL_PD5			0x20
+#define PNL_PD6			0x40
+#define PNL_PD7			0x80
+
+#define PIN_NONE		0
+#define PIN_STROBE		1
+#define PIN_D0			2
+#define PIN_D1			3
+#define PIN_D2			4
+#define PIN_D3			5
+#define PIN_D4			6
+#define PIN_D5			7
+#define PIN_D6			8
+#define PIN_D7			9
+#define PIN_AUTOLF		14
+#define PIN_INITP		16
+#define PIN_SELECP		17
+#define PIN_NOT_SET		127
+
+#define NOT_SET			-1
+
+/* macros to simplify use of the parallel port */
+#define r_ctr(x)        (parport_read_control((x)->port))
+#define r_dtr(x)        (parport_read_data((x)->port))
+#define r_str(x)        (parport_read_status((x)->port))
+#define w_ctr(x, y)     (parport_write_control((x)->port, (y)))
+#define w_dtr(x, y)     (parport_write_data((x)->port, (y)))
+
+/* this defines which bits are to be used and which ones to be ignored */
+/* logical or of the output bits involved in the scan matrix */
+static __u8 scan_mask_o;
+/* logical or of the input bits involved in the scan matrix */
+static __u8 scan_mask_i;
+
+enum input_type {
+	INPUT_TYPE_STD,
+	INPUT_TYPE_KBD,
+};
+
+enum input_state {
+	INPUT_ST_LOW,
+	INPUT_ST_RISING,
+	INPUT_ST_HIGH,
+	INPUT_ST_FALLING,
+};
+
+struct logical_input {
+	struct list_head list;
+	__u64 mask;
+	__u64 value;
+	enum input_type type;
+	enum input_state state;
+	__u8 rise_time, fall_time;
+	__u8 rise_timer, fall_timer, high_timer;
+
+	union {
+		struct {	/* valid when type == INPUT_TYPE_STD */
+			void (*press_fct)(int);
+			void (*release_fct)(int);
+			int press_data;
+			int release_data;
+		} std;
+		struct {	/* valid when type == INPUT_TYPE_KBD */
+			char press_str[sizeof(void *) + sizeof(int)] __nonstring;
+			char repeat_str[sizeof(void *) + sizeof(int)] __nonstring;
+			char release_str[sizeof(void *) + sizeof(int)] __nonstring;
+		} kbd;
+	} u;
+};
+
+static LIST_HEAD(logical_inputs);	/* list of all defined logical inputs */
+
+/* physical contacts history
+ * Physical contacts are a 45 bits string of 9 groups of 5 bits each.
+ * The 8 lower groups correspond to output bits 0 to 7, and the 9th group
+ * corresponds to the ground.
+ * Within each group, bits are stored in the same order as read on the port :
+ * BAPSE (busy=4, ack=3, paper empty=2, select=1, error=0).
+ * So, each __u64 is represented like this :
+ * 0000000000000000000BAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSE
+ * <-----unused------><gnd><d07><d06><d05><d04><d03><d02><d01><d00>
+ */
+
+/* what has just been read from the I/O ports */
+static __u64 phys_read;
+/* previous phys_read */
+static __u64 phys_read_prev;
+/* stabilized phys_read (phys_read|phys_read_prev) */
+static __u64 phys_curr;
+/* previous phys_curr */
+static __u64 phys_prev;
+/* 0 means that at least one logical signal needs be computed */
+static char inputs_stable;
+
+/* these variables are specific to the keypad */
+static struct {
+	bool enabled;
+} keypad;
+
+static char keypad_buffer[KEYPAD_BUFFER];
+static int keypad_buflen;
+static int keypad_start;
+static char keypressed;
+static wait_queue_head_t keypad_read_wait;
+
+/* lcd-specific variables */
+static struct {
+	bool enabled;
+	bool initialized;
+
+	int charset;
+	int proto;
+
+	/* TODO: use union here? */
+	struct {
+		int e;
+		int rs;
+		int rw;
+		int cl;
+		int da;
+		int bl;
+	} pins;
+
+	struct charlcd *charlcd;
+} lcd;
+
+/* Needed only for init */
+static int selected_lcd_type = NOT_SET;
+
+/*
+ * Bit masks to convert LCD signals to parallel port outputs.
+ * _d_ are values for data port, _c_ are for control port.
+ * [0] = signal OFF, [1] = signal ON, [2] = mask
+ */
+#define BIT_CLR		0
+#define BIT_SET		1
+#define BIT_MSK		2
+#define BIT_STATES	3
+/*
+ * one entry for each bit on the LCD
+ */
+#define LCD_BIT_E	0
+#define LCD_BIT_RS	1
+#define LCD_BIT_RW	2
+#define LCD_BIT_BL	3
+#define LCD_BIT_CL	4
+#define LCD_BIT_DA	5
+#define LCD_BITS	6
+
+/*
+ * each bit can be either connected to a DATA or CTRL port
+ */
+#define LCD_PORT_C	0
+#define LCD_PORT_D	1
+#define LCD_PORTS	2
+
+static unsigned char lcd_bits[LCD_PORTS][LCD_BITS][BIT_STATES];
+
+/*
+ * LCD protocols
+ */
+#define LCD_PROTO_PARALLEL      0
+#define LCD_PROTO_SERIAL        1
+#define LCD_PROTO_TI_DA8XX_LCD	2
+
+/*
+ * LCD character sets
+ */
+#define LCD_CHARSET_NORMAL      0
+#define LCD_CHARSET_KS0074      1
+
+/*
+ * LCD types
+ */
+#define LCD_TYPE_NONE		0
+#define LCD_TYPE_CUSTOM		1
+#define LCD_TYPE_OLD		2
+#define LCD_TYPE_KS0074		3
+#define LCD_TYPE_HANTRONIX	4
+#define LCD_TYPE_NEXCOM		5
+
+/*
+ * keypad types
+ */
+#define KEYPAD_TYPE_NONE	0
+#define KEYPAD_TYPE_OLD		1
+#define KEYPAD_TYPE_NEW		2
+#define KEYPAD_TYPE_NEXCOM	3
+
+/*
+ * panel profiles
+ */
+#define PANEL_PROFILE_CUSTOM	0
+#define PANEL_PROFILE_OLD	1
+#define PANEL_PROFILE_NEW	2
+#define PANEL_PROFILE_HANTRONIX	3
+#define PANEL_PROFILE_NEXCOM	4
+#define PANEL_PROFILE_LARGE	5
+
+/*
+ * Construct custom config from the kernel's configuration
+ */
+#define DEFAULT_PARPORT         0
+#define DEFAULT_PROFILE         PANEL_PROFILE_LARGE
+#define DEFAULT_KEYPAD_TYPE     KEYPAD_TYPE_OLD
+#define DEFAULT_LCD_TYPE        LCD_TYPE_OLD
+#define DEFAULT_LCD_HEIGHT      2
+#define DEFAULT_LCD_WIDTH       40
+#define DEFAULT_LCD_CHARSET     LCD_CHARSET_NORMAL
+#define DEFAULT_LCD_PROTO       LCD_PROTO_PARALLEL
+
+#define DEFAULT_LCD_PIN_E       PIN_AUTOLF
+#define DEFAULT_LCD_PIN_RS      PIN_SELECP
+#define DEFAULT_LCD_PIN_RW      PIN_INITP
+#define DEFAULT_LCD_PIN_SCL     PIN_STROBE
+#define DEFAULT_LCD_PIN_SDA     PIN_D0
+#define DEFAULT_LCD_PIN_BL      PIN_NOT_SET
+
+#ifdef CONFIG_PANEL_PARPORT
+#undef DEFAULT_PARPORT
+#define DEFAULT_PARPORT CONFIG_PANEL_PARPORT
+#endif
+
+#ifdef CONFIG_PANEL_PROFILE
+#undef DEFAULT_PROFILE
+#define DEFAULT_PROFILE CONFIG_PANEL_PROFILE
+#endif
+
+#if DEFAULT_PROFILE == 0	/* custom */
+#ifdef CONFIG_PANEL_KEYPAD
+#undef DEFAULT_KEYPAD_TYPE
+#define DEFAULT_KEYPAD_TYPE CONFIG_PANEL_KEYPAD
+#endif
+
+#ifdef CONFIG_PANEL_LCD
+#undef DEFAULT_LCD_TYPE
+#define DEFAULT_LCD_TYPE CONFIG_PANEL_LCD
+#endif
+
+#ifdef CONFIG_PANEL_LCD_HEIGHT
+#undef DEFAULT_LCD_HEIGHT
+#define DEFAULT_LCD_HEIGHT CONFIG_PANEL_LCD_HEIGHT
+#endif
+
+#ifdef CONFIG_PANEL_LCD_WIDTH
+#undef DEFAULT_LCD_WIDTH
+#define DEFAULT_LCD_WIDTH CONFIG_PANEL_LCD_WIDTH
+#endif
+
+#ifdef CONFIG_PANEL_LCD_BWIDTH
+#undef DEFAULT_LCD_BWIDTH
+#define DEFAULT_LCD_BWIDTH CONFIG_PANEL_LCD_BWIDTH
+#endif
+
+#ifdef CONFIG_PANEL_LCD_HWIDTH
+#undef DEFAULT_LCD_HWIDTH
+#define DEFAULT_LCD_HWIDTH CONFIG_PANEL_LCD_HWIDTH
+#endif
+
+#ifdef CONFIG_PANEL_LCD_CHARSET
+#undef DEFAULT_LCD_CHARSET
+#define DEFAULT_LCD_CHARSET CONFIG_PANEL_LCD_CHARSET
+#endif
+
+#ifdef CONFIG_PANEL_LCD_PROTO
+#undef DEFAULT_LCD_PROTO
+#define DEFAULT_LCD_PROTO CONFIG_PANEL_LCD_PROTO
+#endif
+
+#ifdef CONFIG_PANEL_LCD_PIN_E
+#undef DEFAULT_LCD_PIN_E
+#define DEFAULT_LCD_PIN_E CONFIG_PANEL_LCD_PIN_E
+#endif
+
+#ifdef CONFIG_PANEL_LCD_PIN_RS
+#undef DEFAULT_LCD_PIN_RS
+#define DEFAULT_LCD_PIN_RS CONFIG_PANEL_LCD_PIN_RS
+#endif
+
+#ifdef CONFIG_PANEL_LCD_PIN_RW
+#undef DEFAULT_LCD_PIN_RW
+#define DEFAULT_LCD_PIN_RW CONFIG_PANEL_LCD_PIN_RW
+#endif
+
+#ifdef CONFIG_PANEL_LCD_PIN_SCL
+#undef DEFAULT_LCD_PIN_SCL
+#define DEFAULT_LCD_PIN_SCL CONFIG_PANEL_LCD_PIN_SCL
+#endif
+
+#ifdef CONFIG_PANEL_LCD_PIN_SDA
+#undef DEFAULT_LCD_PIN_SDA
+#define DEFAULT_LCD_PIN_SDA CONFIG_PANEL_LCD_PIN_SDA
+#endif
+
+#ifdef CONFIG_PANEL_LCD_PIN_BL
+#undef DEFAULT_LCD_PIN_BL
+#define DEFAULT_LCD_PIN_BL CONFIG_PANEL_LCD_PIN_BL
+#endif
+
+#endif /* DEFAULT_PROFILE == 0 */
+
+/* global variables */
+
+/* Device single-open policy control */
+static atomic_t keypad_available = ATOMIC_INIT(1);
+
+static struct pardevice *pprt;
+
+static int keypad_initialized;
+
+static DEFINE_SPINLOCK(pprt_lock);
+static struct timer_list scan_timer;
+
+MODULE_DESCRIPTION("Generic parallel port LCD/Keypad driver");
+
+static int parport = DEFAULT_PARPORT;
+module_param(parport, int, 0000);
+MODULE_PARM_DESC(parport, "Parallel port index (0=lpt1, 1=lpt2, ...)");
+
+static int profile = DEFAULT_PROFILE;
+module_param(profile, int, 0000);
+MODULE_PARM_DESC(profile,
+		 "1=16x2 old kp; 2=serial 16x2, new kp; 3=16x2 hantronix; "
+		 "4=16x2 nexcom; default=40x2, old kp");
+
+static int keypad_type = NOT_SET;
+module_param(keypad_type, int, 0000);
+MODULE_PARM_DESC(keypad_type,
+		 "Keypad type: 0=none, 1=old 6 keys, 2=new 6+1 keys, 3=nexcom 4 keys");
+
+static int lcd_type = NOT_SET;
+module_param(lcd_type, int, 0000);
+MODULE_PARM_DESC(lcd_type,
+		 "LCD type: 0=none, 1=compiled-in, 2=old, 3=serial ks0074, 4=hantronix, 5=nexcom");
+
+static int lcd_height = NOT_SET;
+module_param(lcd_height, int, 0000);
+MODULE_PARM_DESC(lcd_height, "Number of lines on the LCD");
+
+static int lcd_width = NOT_SET;
+module_param(lcd_width, int, 0000);
+MODULE_PARM_DESC(lcd_width, "Number of columns on the LCD");
+
+static int lcd_bwidth = NOT_SET;	/* internal buffer width (usually 40) */
+module_param(lcd_bwidth, int, 0000);
+MODULE_PARM_DESC(lcd_bwidth, "Internal LCD line width (40)");
+
+static int lcd_hwidth = NOT_SET;	/* hardware buffer width (usually 64) */
+module_param(lcd_hwidth, int, 0000);
+MODULE_PARM_DESC(lcd_hwidth, "LCD line hardware address (64)");
+
+static int lcd_charset = NOT_SET;
+module_param(lcd_charset, int, 0000);
+MODULE_PARM_DESC(lcd_charset, "LCD character set: 0=standard, 1=KS0074");
+
+static int lcd_proto = NOT_SET;
+module_param(lcd_proto, int, 0000);
+MODULE_PARM_DESC(lcd_proto,
+		 "LCD communication: 0=parallel (//), 1=serial, 2=TI LCD Interface");
+
+/*
+ * These are the parallel port pins the LCD control signals are connected to.
+ * Set this to 0 if the signal is not used. Set it to its opposite value
+ * (negative) if the signal is negated. -MAXINT is used to indicate that the
+ * pin has not been explicitly specified.
+ *
+ * WARNING! no check will be performed about collisions with keypad !
+ */
+
+static int lcd_e_pin  = PIN_NOT_SET;
+module_param(lcd_e_pin, int, 0000);
+MODULE_PARM_DESC(lcd_e_pin,
+		 "# of the // port pin connected to LCD 'E' signal, with polarity (-17..17)");
+
+static int lcd_rs_pin = PIN_NOT_SET;
+module_param(lcd_rs_pin, int, 0000);
+MODULE_PARM_DESC(lcd_rs_pin,
+		 "# of the // port pin connected to LCD 'RS' signal, with polarity (-17..17)");
+
+static int lcd_rw_pin = PIN_NOT_SET;
+module_param(lcd_rw_pin, int, 0000);
+MODULE_PARM_DESC(lcd_rw_pin,
+		 "# of the // port pin connected to LCD 'RW' signal, with polarity (-17..17)");
+
+static int lcd_cl_pin = PIN_NOT_SET;
+module_param(lcd_cl_pin, int, 0000);
+MODULE_PARM_DESC(lcd_cl_pin,
+		 "# of the // port pin connected to serial LCD 'SCL' signal, with polarity (-17..17)");
+
+static int lcd_da_pin = PIN_NOT_SET;
+module_param(lcd_da_pin, int, 0000);
+MODULE_PARM_DESC(lcd_da_pin,
+		 "# of the // port pin connected to serial LCD 'SDA' signal, with polarity (-17..17)");
+
+static int lcd_bl_pin = PIN_NOT_SET;
+module_param(lcd_bl_pin, int, 0000);
+MODULE_PARM_DESC(lcd_bl_pin,
+		 "# of the // port pin connected to LCD backlight, with polarity (-17..17)");
+
+/* Deprecated module parameters - consider not using them anymore */
+
+static int lcd_enabled = NOT_SET;
+module_param(lcd_enabled, int, 0000);
+MODULE_PARM_DESC(lcd_enabled, "Deprecated option, use lcd_type instead");
+
+static int keypad_enabled = NOT_SET;
+module_param(keypad_enabled, int, 0000);
+MODULE_PARM_DESC(keypad_enabled, "Deprecated option, use keypad_type instead");
+
+/* for some LCD drivers (ks0074) we need a charset conversion table. */
+static const unsigned char lcd_char_conv_ks0074[256] = {
+	/*          0|8   1|9   2|A   3|B   4|C   5|D   6|E   7|F */
+	/* 0x00 */ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+	/* 0x08 */ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+	/* 0x10 */ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+	/* 0x18 */ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+	/* 0x20 */ 0x20, 0x21, 0x22, 0x23, 0xa2, 0x25, 0x26, 0x27,
+	/* 0x28 */ 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
+	/* 0x30 */ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
+	/* 0x38 */ 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
+	/* 0x40 */ 0xa0, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
+	/* 0x48 */ 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
+	/* 0x50 */ 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
+	/* 0x58 */ 0x58, 0x59, 0x5a, 0xfa, 0xfb, 0xfc, 0x1d, 0xc4,
+	/* 0x60 */ 0x96, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
+	/* 0x68 */ 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
+	/* 0x70 */ 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
+	/* 0x78 */ 0x78, 0x79, 0x7a, 0xfd, 0xfe, 0xff, 0xce, 0x20,
+	/* 0x80 */ 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
+	/* 0x88 */ 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
+	/* 0x90 */ 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
+	/* 0x98 */ 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
+	/* 0xA0 */ 0x20, 0x40, 0xb1, 0xa1, 0x24, 0xa3, 0xfe, 0x5f,
+	/* 0xA8 */ 0x22, 0xc8, 0x61, 0x14, 0x97, 0x2d, 0xad, 0x96,
+	/* 0xB0 */ 0x80, 0x8c, 0x82, 0x83, 0x27, 0x8f, 0x86, 0xdd,
+	/* 0xB8 */ 0x2c, 0x81, 0x6f, 0x15, 0x8b, 0x8a, 0x84, 0x60,
+	/* 0xC0 */ 0xe2, 0xe2, 0xe2, 0x5b, 0x5b, 0xae, 0xbc, 0xa9,
+	/* 0xC8 */ 0xc5, 0xbf, 0xc6, 0xf1, 0xe3, 0xe3, 0xe3, 0xe3,
+	/* 0xD0 */ 0x44, 0x5d, 0xa8, 0xe4, 0xec, 0xec, 0x5c, 0x78,
+	/* 0xD8 */ 0xab, 0xa6, 0xe5, 0x5e, 0x5e, 0xe6, 0xaa, 0xbe,
+	/* 0xE0 */ 0x7f, 0xe7, 0xaf, 0x7b, 0x7b, 0xaf, 0xbd, 0xc8,
+	/* 0xE8 */ 0xa4, 0xa5, 0xc7, 0xf6, 0xa7, 0xe8, 0x69, 0x69,
+	/* 0xF0 */ 0xed, 0x7d, 0xa8, 0xe4, 0xec, 0x5c, 0x5c, 0x25,
+	/* 0xF8 */ 0xac, 0xa6, 0xea, 0xef, 0x7e, 0xeb, 0xb2, 0x79,
+};
+
+static const char old_keypad_profile[][4][9] = {
+	{"S0", "Left\n", "Left\n", ""},
+	{"S1", "Down\n", "Down\n", ""},
+	{"S2", "Up\n", "Up\n", ""},
+	{"S3", "Right\n", "Right\n", ""},
+	{"S4", "Esc\n", "Esc\n", ""},
+	{"S5", "Ret\n", "Ret\n", ""},
+	{"", "", "", ""}
+};
+
+/* signals, press, repeat, release */
+static const char new_keypad_profile[][4][9] = {
+	{"S0", "Left\n", "Left\n", ""},
+	{"S1", "Down\n", "Down\n", ""},
+	{"S2", "Up\n", "Up\n", ""},
+	{"S3", "Right\n", "Right\n", ""},
+	{"S4s5", "", "Esc\n", "Esc\n"},
+	{"s4S5", "", "Ret\n", "Ret\n"},
+	{"S4S5", "Help\n", "", ""},
+	/* add new signals above this line */
+	{"", "", "", ""}
+};
+
+/* signals, press, repeat, release */
+static const char nexcom_keypad_profile[][4][9] = {
+	{"a-p-e-", "Down\n", "Down\n", ""},
+	{"a-p-E-", "Ret\n", "Ret\n", ""},
+	{"a-P-E-", "Esc\n", "Esc\n", ""},
+	{"a-P-e-", "Up\n", "Up\n", ""},
+	/* add new signals above this line */
+	{"", "", "", ""}
+};
+
+static const char (*keypad_profile)[4][9] = old_keypad_profile;
+
+static DECLARE_BITMAP(bits, LCD_BITS);
+
+static void lcd_get_bits(unsigned int port, int *val)
+{
+	unsigned int bit, state;
+
+	for (bit = 0; bit < LCD_BITS; bit++) {
+		state = test_bit(bit, bits) ? BIT_SET : BIT_CLR;
+		*val &= lcd_bits[port][bit][BIT_MSK];
+		*val |= lcd_bits[port][bit][state];
+	}
+}
+
+/* sets data port bits according to current signals values */
+static int set_data_bits(void)
+{
+	int val;
+
+	val = r_dtr(pprt);
+	lcd_get_bits(LCD_PORT_D, &val);
+	w_dtr(pprt, val);
+	return val;
+}
+
+/* sets ctrl port bits according to current signals values */
+static int set_ctrl_bits(void)
+{
+	int val;
+
+	val = r_ctr(pprt);
+	lcd_get_bits(LCD_PORT_C, &val);
+	w_ctr(pprt, val);
+	return val;
+}
+
+/* sets ctrl & data port bits according to current signals values */
+static void panel_set_bits(void)
+{
+	set_data_bits();
+	set_ctrl_bits();
+}
+
+/*
+ * Converts a parallel port pin (from -25 to 25) to data and control ports
+ * masks, and data and control port bits. The signal will be considered
+ * unconnected if it's on pin 0 or an invalid pin (<-25 or >25).
+ *
+ * Result will be used this way :
+ *   out(dport, in(dport) & d_val[2] | d_val[signal_state])
+ *   out(cport, in(cport) & c_val[2] | c_val[signal_state])
+ */
+static void pin_to_bits(int pin, unsigned char *d_val, unsigned char *c_val)
+{
+	int d_bit, c_bit, inv;
+
+	d_val[0] = 0;
+	c_val[0] = 0;
+	d_val[1] = 0;
+	c_val[1] = 0;
+	d_val[2] = 0xFF;
+	c_val[2] = 0xFF;
+
+	if (pin == 0)
+		return;
+
+	inv = (pin < 0);
+	if (inv)
+		pin = -pin;
+
+	d_bit = 0;
+	c_bit = 0;
+
+	switch (pin) {
+	case PIN_STROBE:	/* strobe, inverted */
+		c_bit = PNL_PSTROBE;
+		inv = !inv;
+		break;
+	case PIN_D0...PIN_D7:	/* D0 - D7 = 2 - 9 */
+		d_bit = 1 << (pin - 2);
+		break;
+	case PIN_AUTOLF:	/* autofeed, inverted */
+		c_bit = PNL_PAUTOLF;
+		inv = !inv;
+		break;
+	case PIN_INITP:		/* init, direct */
+		c_bit = PNL_PINITP;
+		break;
+	case PIN_SELECP:	/* select_in, inverted */
+		c_bit = PNL_PSELECP;
+		inv = !inv;
+		break;
+	default:		/* unknown pin, ignore */
+		break;
+	}
+
+	if (c_bit) {
+		c_val[2] &= ~c_bit;
+		c_val[!inv] = c_bit;
+	} else if (d_bit) {
+		d_val[2] &= ~d_bit;
+		d_val[!inv] = d_bit;
+	}
+}
+
+/*
+ * send a serial byte to the LCD panel. The caller is responsible for locking
+ * if needed.
+ */
+static void lcd_send_serial(int byte)
+{
+	int bit;
+
+	/*
+	 * the data bit is set on D0, and the clock on STROBE.
+	 * LCD reads D0 on STROBE's rising edge.
+	 */
+	for (bit = 0; bit < 8; bit++) {
+		clear_bit(LCD_BIT_CL, bits);	/* CLK low */
+		panel_set_bits();
+		if (byte & 1) {
+			set_bit(LCD_BIT_DA, bits);
+		} else {
+			clear_bit(LCD_BIT_DA, bits);
+		}
+
+		panel_set_bits();
+		udelay(2);  /* maintain the data during 2 us before CLK up */
+		set_bit(LCD_BIT_CL, bits);	/* CLK high */
+		panel_set_bits();
+		udelay(1);  /* maintain the strobe during 1 us */
+		byte >>= 1;
+	}
+}
+
+/* turn the backlight on or off */
+static void lcd_backlight(struct charlcd *charlcd, enum charlcd_onoff on)
+{
+	if (lcd.pins.bl == PIN_NONE)
+		return;
+
+	/* The backlight is activated by setting the AUTOFEED line to +5V  */
+	spin_lock_irq(&pprt_lock);
+	if (on)
+		set_bit(LCD_BIT_BL, bits);
+	else
+		clear_bit(LCD_BIT_BL, bits);
+	panel_set_bits();
+	spin_unlock_irq(&pprt_lock);
+}
+
+/* send a command to the LCD panel in serial mode */
+static void lcd_write_cmd_s(struct hd44780_common *hdc, int cmd)
+{
+	spin_lock_irq(&pprt_lock);
+	lcd_send_serial(0x1F);	/* R/W=W, RS=0 */
+	lcd_send_serial(cmd & 0x0F);
+	lcd_send_serial((cmd >> 4) & 0x0F);
+	udelay(40);		/* the shortest command takes at least 40 us */
+	spin_unlock_irq(&pprt_lock);
+}
+
+/* send data to the LCD panel in serial mode */
+static void lcd_write_data_s(struct hd44780_common *hdc, int data)
+{
+	spin_lock_irq(&pprt_lock);
+	lcd_send_serial(0x5F);	/* R/W=W, RS=1 */
+	lcd_send_serial(data & 0x0F);
+	lcd_send_serial((data >> 4) & 0x0F);
+	udelay(40);		/* the shortest data takes at least 40 us */
+	spin_unlock_irq(&pprt_lock);
+}
+
+/* send a command to the LCD panel in 8 bits parallel mode */
+static void lcd_write_cmd_p8(struct hd44780_common *hdc, int cmd)
+{
+	spin_lock_irq(&pprt_lock);
+	/* present the data to the data port */
+	w_dtr(pprt, cmd);
+	udelay(20);	/* maintain the data during 20 us before the strobe */
+
+	set_bit(LCD_BIT_E, bits);
+	clear_bit(LCD_BIT_RS, bits);
+	clear_bit(LCD_BIT_RW, bits);
+	set_ctrl_bits();
+
+	udelay(40);	/* maintain the strobe during 40 us */
+
+	clear_bit(LCD_BIT_E, bits);
+	set_ctrl_bits();
+
+	udelay(120);	/* the shortest command takes at least 120 us */
+	spin_unlock_irq(&pprt_lock);
+}
+
+/* send data to the LCD panel in 8 bits parallel mode */
+static void lcd_write_data_p8(struct hd44780_common *hdc, int data)
+{
+	spin_lock_irq(&pprt_lock);
+	/* present the data to the data port */
+	w_dtr(pprt, data);
+	udelay(20);	/* maintain the data during 20 us before the strobe */
+
+	set_bit(LCD_BIT_E, bits);
+	set_bit(LCD_BIT_RS, bits);
+	clear_bit(LCD_BIT_RW, bits);
+	set_ctrl_bits();
+
+	udelay(40);	/* maintain the strobe during 40 us */
+
+	clear_bit(LCD_BIT_E, bits);
+	set_ctrl_bits();
+
+	udelay(45);	/* the shortest data takes at least 45 us */
+	spin_unlock_irq(&pprt_lock);
+}
+
+/* send a command to the TI LCD panel */
+static void lcd_write_cmd_tilcd(struct hd44780_common *hdc, int cmd)
+{
+	spin_lock_irq(&pprt_lock);
+	/* present the data to the control port */
+	w_ctr(pprt, cmd);
+	udelay(60);
+	spin_unlock_irq(&pprt_lock);
+}
+
+/* send data to the TI LCD panel */
+static void lcd_write_data_tilcd(struct hd44780_common *hdc, int data)
+{
+	spin_lock_irq(&pprt_lock);
+	/* present the data to the data port */
+	w_dtr(pprt, data);
+	udelay(60);
+	spin_unlock_irq(&pprt_lock);
+}
+
+static const struct charlcd_ops charlcd_ops = {
+	.backlight	= lcd_backlight,
+	.print		= hd44780_common_print,
+	.gotoxy		= hd44780_common_gotoxy,
+	.home		= hd44780_common_home,
+	.clear_display	= hd44780_common_clear_display,
+	.init_display	= hd44780_common_init_display,
+	.shift_cursor	= hd44780_common_shift_cursor,
+	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
+	.cursor		= hd44780_common_cursor,
+	.blink		= hd44780_common_blink,
+	.fontsize	= hd44780_common_fontsize,
+	.lines		= hd44780_common_lines,
+	.redefine_char	= hd44780_common_redefine_char,
+};
+
+/* initialize the LCD driver */
+static void lcd_init(void)
+{
+	struct charlcd *charlcd;
+	struct hd44780_common *hdc;
+
+	hdc = hd44780_common_alloc();
+	if (!hdc)
+		return;
+
+	charlcd = charlcd_alloc();
+	if (!charlcd) {
+		kfree(hdc);
+		return;
+	}
+
+	hdc->hd44780 = &lcd;
+	charlcd->drvdata = hdc;
+
+	/*
+	 * Init lcd struct with load-time values to preserve exact
+	 * current functionality (at least for now).
+	 */
+	charlcd->height = lcd_height;
+	charlcd->width = lcd_width;
+	hdc->bwidth = lcd_bwidth;
+	hdc->hwidth = lcd_hwidth;
+
+	switch (selected_lcd_type) {
+	case LCD_TYPE_OLD:
+		/* parallel mode, 8 bits */
+		lcd.proto = LCD_PROTO_PARALLEL;
+		lcd.charset = LCD_CHARSET_NORMAL;
+		lcd.pins.e = PIN_STROBE;
+		lcd.pins.rs = PIN_AUTOLF;
+
+		charlcd->width = 40;
+		hdc->bwidth = 40;
+		hdc->hwidth = 64;
+		charlcd->height = 2;
+		break;
+	case LCD_TYPE_KS0074:
+		/* serial mode, ks0074 */
+		lcd.proto = LCD_PROTO_SERIAL;
+		lcd.charset = LCD_CHARSET_KS0074;
+		lcd.pins.bl = PIN_AUTOLF;
+		lcd.pins.cl = PIN_STROBE;
+		lcd.pins.da = PIN_D0;
+
+		charlcd->width = 16;
+		hdc->bwidth = 40;
+		hdc->hwidth = 16;
+		charlcd->height = 2;
+		break;
+	case LCD_TYPE_NEXCOM:
+		/* parallel mode, 8 bits, generic */
+		lcd.proto = LCD_PROTO_PARALLEL;
+		lcd.charset = LCD_CHARSET_NORMAL;
+		lcd.pins.e = PIN_AUTOLF;
+		lcd.pins.rs = PIN_SELECP;
+		lcd.pins.rw = PIN_INITP;
+
+		charlcd->width = 16;
+		hdc->bwidth = 40;
+		hdc->hwidth = 64;
+		charlcd->height = 2;
+		break;
+	case LCD_TYPE_CUSTOM:
+		/* customer-defined */
+		lcd.proto = DEFAULT_LCD_PROTO;
+		lcd.charset = DEFAULT_LCD_CHARSET;
+		/* default geometry will be set later */
+		break;
+	case LCD_TYPE_HANTRONIX:
+		/* parallel mode, 8 bits, hantronix-like */
+	default:
+		lcd.proto = LCD_PROTO_PARALLEL;
+		lcd.charset = LCD_CHARSET_NORMAL;
+		lcd.pins.e = PIN_STROBE;
+		lcd.pins.rs = PIN_SELECP;
+
+		charlcd->width = 16;
+		hdc->bwidth = 40;
+		hdc->hwidth = 64;
+		charlcd->height = 2;
+		break;
+	}
+
+	/* Overwrite with module params set on loading */
+	if (lcd_height != NOT_SET)
+		charlcd->height = lcd_height;
+	if (lcd_width != NOT_SET)
+		charlcd->width = lcd_width;
+	if (lcd_bwidth != NOT_SET)
+		hdc->bwidth = lcd_bwidth;
+	if (lcd_hwidth != NOT_SET)
+		hdc->hwidth = lcd_hwidth;
+	if (lcd_charset != NOT_SET)
+		lcd.charset = lcd_charset;
+	if (lcd_proto != NOT_SET)
+		lcd.proto = lcd_proto;
+	if (lcd_e_pin != PIN_NOT_SET)
+		lcd.pins.e = lcd_e_pin;
+	if (lcd_rs_pin != PIN_NOT_SET)
+		lcd.pins.rs = lcd_rs_pin;
+	if (lcd_rw_pin != PIN_NOT_SET)
+		lcd.pins.rw = lcd_rw_pin;
+	if (lcd_cl_pin != PIN_NOT_SET)
+		lcd.pins.cl = lcd_cl_pin;
+	if (lcd_da_pin != PIN_NOT_SET)
+		lcd.pins.da = lcd_da_pin;
+	if (lcd_bl_pin != PIN_NOT_SET)
+		lcd.pins.bl = lcd_bl_pin;
+
+	/* this is used to catch wrong and default values */
+	if (charlcd->width <= 0)
+		charlcd->width = DEFAULT_LCD_WIDTH;
+	if (hdc->bwidth <= 0)
+		hdc->bwidth = DEFAULT_LCD_BWIDTH;
+	if (hdc->hwidth <= 0)
+		hdc->hwidth = DEFAULT_LCD_HWIDTH;
+	if (charlcd->height <= 0)
+		charlcd->height = DEFAULT_LCD_HEIGHT;
+
+	if (lcd.proto == LCD_PROTO_SERIAL) {	/* SERIAL */
+		charlcd->ops = &charlcd_ops;
+		hdc->write_data = lcd_write_data_s;
+		hdc->write_cmd = lcd_write_cmd_s;
+
+		if (lcd.pins.cl == PIN_NOT_SET)
+			lcd.pins.cl = DEFAULT_LCD_PIN_SCL;
+		if (lcd.pins.da == PIN_NOT_SET)
+			lcd.pins.da = DEFAULT_LCD_PIN_SDA;
+
+	} else if (lcd.proto == LCD_PROTO_PARALLEL) {	/* PARALLEL */
+		charlcd->ops = &charlcd_ops;
+		hdc->write_data = lcd_write_data_p8;
+		hdc->write_cmd = lcd_write_cmd_p8;
+
+		if (lcd.pins.e == PIN_NOT_SET)
+			lcd.pins.e = DEFAULT_LCD_PIN_E;
+		if (lcd.pins.rs == PIN_NOT_SET)
+			lcd.pins.rs = DEFAULT_LCD_PIN_RS;
+		if (lcd.pins.rw == PIN_NOT_SET)
+			lcd.pins.rw = DEFAULT_LCD_PIN_RW;
+	} else {
+		charlcd->ops = &charlcd_ops;
+		hdc->write_data = lcd_write_data_tilcd;
+		hdc->write_cmd = lcd_write_cmd_tilcd;
+	}
+
+	if (lcd.pins.bl == PIN_NOT_SET)
+		lcd.pins.bl = DEFAULT_LCD_PIN_BL;
+
+	if (lcd.pins.e == PIN_NOT_SET)
+		lcd.pins.e = PIN_NONE;
+	if (lcd.pins.rs == PIN_NOT_SET)
+		lcd.pins.rs = PIN_NONE;
+	if (lcd.pins.rw == PIN_NOT_SET)
+		lcd.pins.rw = PIN_NONE;
+	if (lcd.pins.bl == PIN_NOT_SET)
+		lcd.pins.bl = PIN_NONE;
+	if (lcd.pins.cl == PIN_NOT_SET)
+		lcd.pins.cl = PIN_NONE;
+	if (lcd.pins.da == PIN_NOT_SET)
+		lcd.pins.da = PIN_NONE;
+
+	if (lcd.charset == NOT_SET)
+		lcd.charset = DEFAULT_LCD_CHARSET;
+
+	if (lcd.charset == LCD_CHARSET_KS0074)
+		charlcd->char_conv = lcd_char_conv_ks0074;
+	else
+		charlcd->char_conv = NULL;
+
+	pin_to_bits(lcd.pins.e, lcd_bits[LCD_PORT_D][LCD_BIT_E],
+		    lcd_bits[LCD_PORT_C][LCD_BIT_E]);
+	pin_to_bits(lcd.pins.rs, lcd_bits[LCD_PORT_D][LCD_BIT_RS],
+		    lcd_bits[LCD_PORT_C][LCD_BIT_RS]);
+	pin_to_bits(lcd.pins.rw, lcd_bits[LCD_PORT_D][LCD_BIT_RW],
+		    lcd_bits[LCD_PORT_C][LCD_BIT_RW]);
+	pin_to_bits(lcd.pins.bl, lcd_bits[LCD_PORT_D][LCD_BIT_BL],
+		    lcd_bits[LCD_PORT_C][LCD_BIT_BL]);
+	pin_to_bits(lcd.pins.cl, lcd_bits[LCD_PORT_D][LCD_BIT_CL],
+		    lcd_bits[LCD_PORT_C][LCD_BIT_CL]);
+	pin_to_bits(lcd.pins.da, lcd_bits[LCD_PORT_D][LCD_BIT_DA],
+		    lcd_bits[LCD_PORT_C][LCD_BIT_DA]);
+
+	lcd.charlcd = charlcd;
+	lcd.initialized = true;
+}
+
+/*
+ * These are the file operation function for user access to /dev/keypad
+ */
+
+static ssize_t keypad_read(struct file *file,
+			   char __user *buf, size_t count, loff_t *ppos)
+{
+	unsigned i = *ppos;
+	char __user *tmp = buf;
+
+	if (keypad_buflen == 0) {
+		if (file->f_flags & O_NONBLOCK)
+			return -EAGAIN;
+
+		if (wait_event_interruptible(keypad_read_wait,
+					     keypad_buflen != 0))
+			return -EINTR;
+	}
+
+	for (; count-- > 0 && (keypad_buflen > 0);
+	     ++i, ++tmp, --keypad_buflen) {
+		put_user(keypad_buffer[keypad_start], tmp);
+		keypad_start = (keypad_start + 1) % KEYPAD_BUFFER;
+	}
+	*ppos = i;
+
+	return tmp - buf;
+}
+
+static int keypad_open(struct inode *inode, struct file *file)
+{
+	int ret;
+
+	ret = -EBUSY;
+	if (!atomic_dec_and_test(&keypad_available))
+		goto fail;	/* open only once at a time */
+
+	ret = -EPERM;
+	if (file->f_mode & FMODE_WRITE)	/* device is read-only */
+		goto fail;
+
+	keypad_buflen = 0;	/* flush the buffer on opening */
+	return 0;
+ fail:
+	atomic_inc(&keypad_available);
+	return ret;
+}
+
+static int keypad_release(struct inode *inode, struct file *file)
+{
+	atomic_inc(&keypad_available);
+	return 0;
+}
+
+static const struct file_operations keypad_fops = {
+	.read    = keypad_read,		/* read */
+	.open    = keypad_open,		/* open */
+	.release = keypad_release,	/* close */
+	.llseek  = default_llseek,
+};
+
+static struct miscdevice keypad_dev = {
+	.minor	= KEYPAD_MINOR,
+	.name	= "keypad",
+	.fops	= &keypad_fops,
+};
+
+static void keypad_send_key(const char *string, int max_len)
+{
+	/* send the key to the device only if a process is attached to it. */
+	if (!atomic_read(&keypad_available)) {
+		while (max_len-- && keypad_buflen < KEYPAD_BUFFER && *string) {
+			keypad_buffer[(keypad_start + keypad_buflen++) %
+				      KEYPAD_BUFFER] = *string++;
+		}
+		wake_up_interruptible(&keypad_read_wait);
+	}
+}
+
+/* this function scans all the bits involving at least one logical signal,
+ * and puts the results in the bitfield "phys_read" (one bit per established
+ * contact), and sets "phys_read_prev" to "phys_read".
+ *
+ * Note: to debounce input signals, we will only consider as switched a signal
+ * which is stable across 2 measures. Signals which are different between two
+ * reads will be kept as they previously were in their logical form (phys_prev).
+ * A signal which has just switched will have a 1 in
+ * (phys_read ^ phys_read_prev).
+ */
+static void phys_scan_contacts(void)
+{
+	int bit, bitval;
+	char oldval;
+	char bitmask;
+	char gndmask;
+
+	phys_prev = phys_curr;
+	phys_read_prev = phys_read;
+	phys_read = 0;		/* flush all signals */
+
+	/* keep track of old value, with all outputs disabled */
+	oldval = r_dtr(pprt) | scan_mask_o;
+	/* activate all keyboard outputs (active low) */
+	w_dtr(pprt, oldval & ~scan_mask_o);
+
+	/* will have a 1 for each bit set to gnd */
+	bitmask = PNL_PINPUT(r_str(pprt)) & scan_mask_i;
+	/* disable all matrix signals */
+	w_dtr(pprt, oldval);
+
+	/* now that all outputs are cleared, the only active input bits are
+	 * directly connected to the ground
+	 */
+
+	/* 1 for each grounded input */
+	gndmask = PNL_PINPUT(r_str(pprt)) & scan_mask_i;
+
+	/* grounded inputs are signals 40-44 */
+	phys_read |= (__u64)gndmask << 40;
+
+	if (bitmask != gndmask) {
+		/*
+		 * since clearing the outputs changed some inputs, we know
+		 * that some input signals are currently tied to some outputs.
+		 * So we'll scan them.
+		 */
+		for (bit = 0; bit < 8; bit++) {
+			bitval = BIT(bit);
+
+			if (!(scan_mask_o & bitval))	/* skip unused bits */
+				continue;
+
+			w_dtr(pprt, oldval & ~bitval);	/* enable this output */
+			bitmask = PNL_PINPUT(r_str(pprt)) & ~gndmask;
+			phys_read |= (__u64)bitmask << (5 * bit);
+		}
+		w_dtr(pprt, oldval);	/* disable all outputs */
+	}
+	/*
+	 * this is easy: use old bits when they are flapping,
+	 * use new ones when stable
+	 */
+	phys_curr = (phys_prev & (phys_read ^ phys_read_prev)) |
+		    (phys_read & ~(phys_read ^ phys_read_prev));
+}
+
+static inline int input_state_high(struct logical_input *input)
+{
+#if 0
+	/* FIXME:
+	 * this is an invalid test. It tries to catch
+	 * transitions from single-key to multiple-key, but
+	 * doesn't take into account the contacts polarity.
+	 * The only solution to the problem is to parse keys
+	 * from the most complex to the simplest combinations,
+	 * and mark them as 'caught' once a combination
+	 * matches, then unmatch it for all other ones.
+	 */
+
+	/* try to catch dangerous transitions cases :
+	 * someone adds a bit, so this signal was a false
+	 * positive resulting from a transition. We should
+	 * invalidate the signal immediately and not call the
+	 * release function.
+	 * eg: 0 -(press A)-> A -(press B)-> AB : don't match A's release.
+	 */
+	if (((phys_prev & input->mask) == input->value) &&
+	    ((phys_curr & input->mask) >  input->value)) {
+		input->state = INPUT_ST_LOW; /* invalidate */
+		return 1;
+	}
+#endif
+
+	if ((phys_curr & input->mask) == input->value) {
+		if ((input->type == INPUT_TYPE_STD) &&
+		    (input->high_timer == 0)) {
+			input->high_timer++;
+			if (input->u.std.press_fct)
+				input->u.std.press_fct(input->u.std.press_data);
+		} else if (input->type == INPUT_TYPE_KBD) {
+			/* will turn on the light */
+			keypressed = 1;
+
+			if (input->high_timer == 0) {
+				char *press_str = input->u.kbd.press_str;
+
+				if (press_str[0]) {
+					int s = sizeof(input->u.kbd.press_str);
+
+					keypad_send_key(press_str, s);
+				}
+			}
+
+			if (input->u.kbd.repeat_str[0]) {
+				char *repeat_str = input->u.kbd.repeat_str;
+
+				if (input->high_timer >= KEYPAD_REP_START) {
+					int s = sizeof(input->u.kbd.repeat_str);
+
+					input->high_timer -= KEYPAD_REP_DELAY;
+					keypad_send_key(repeat_str, s);
+				}
+				/* we will need to come back here soon */
+				inputs_stable = 0;
+			}
+
+			if (input->high_timer < 255)
+				input->high_timer++;
+		}
+		return 1;
+	}
+
+	/* else signal falling down. Let's fall through. */
+	input->state = INPUT_ST_FALLING;
+	input->fall_timer = 0;
+
+	return 0;
+}
+
+static inline void input_state_falling(struct logical_input *input)
+{
+#if 0
+	/* FIXME !!! same comment as in input_state_high */
+	if (((phys_prev & input->mask) == input->value) &&
+	    ((phys_curr & input->mask) >  input->value)) {
+		input->state = INPUT_ST_LOW;	/* invalidate */
+		return;
+	}
+#endif
+
+	if ((phys_curr & input->mask) == input->value) {
+		if (input->type == INPUT_TYPE_KBD) {
+			/* will turn on the light */
+			keypressed = 1;
+
+			if (input->u.kbd.repeat_str[0]) {
+				char *repeat_str = input->u.kbd.repeat_str;
+
+				if (input->high_timer >= KEYPAD_REP_START) {
+					int s = sizeof(input->u.kbd.repeat_str);
+
+					input->high_timer -= KEYPAD_REP_DELAY;
+					keypad_send_key(repeat_str, s);
+				}
+				/* we will need to come back here soon */
+				inputs_stable = 0;
+			}
+
+			if (input->high_timer < 255)
+				input->high_timer++;
+		}
+		input->state = INPUT_ST_HIGH;
+	} else if (input->fall_timer >= input->fall_time) {
+		/* call release event */
+		if (input->type == INPUT_TYPE_STD) {
+			void (*release_fct)(int) = input->u.std.release_fct;
+
+			if (release_fct)
+				release_fct(input->u.std.release_data);
+		} else if (input->type == INPUT_TYPE_KBD) {
+			char *release_str = input->u.kbd.release_str;
+
+			if (release_str[0]) {
+				int s = sizeof(input->u.kbd.release_str);
+
+				keypad_send_key(release_str, s);
+			}
+		}
+
+		input->state = INPUT_ST_LOW;
+	} else {
+		input->fall_timer++;
+		inputs_stable = 0;
+	}
+}
+
+static void panel_process_inputs(void)
+{
+	struct logical_input *input;
+
+	keypressed = 0;
+	inputs_stable = 1;
+	list_for_each_entry(input, &logical_inputs, list) {
+		switch (input->state) {
+		case INPUT_ST_LOW:
+			if ((phys_curr & input->mask) != input->value)
+				break;
+			/* if all needed ones were already set previously,
+			 * this means that this logical signal has been
+			 * activated by the releasing of another combined
+			 * signal, so we don't want to match.
+			 * eg: AB -(release B)-> A -(release A)-> 0 :
+			 *     don't match A.
+			 */
+			if ((phys_prev & input->mask) == input->value)
+				break;
+			input->rise_timer = 0;
+			input->state = INPUT_ST_RISING;
+			fallthrough;
+		case INPUT_ST_RISING:
+			if ((phys_curr & input->mask) != input->value) {
+				input->state = INPUT_ST_LOW;
+				break;
+			}
+			if (input->rise_timer < input->rise_time) {
+				inputs_stable = 0;
+				input->rise_timer++;
+				break;
+			}
+			input->high_timer = 0;
+			input->state = INPUT_ST_HIGH;
+			fallthrough;
+		case INPUT_ST_HIGH:
+			if (input_state_high(input))
+				break;
+			fallthrough;
+		case INPUT_ST_FALLING:
+			input_state_falling(input);
+		}
+	}
+}
+
+static void panel_scan_timer(struct timer_list *unused)
+{
+	if (keypad.enabled && keypad_initialized) {
+		if (spin_trylock_irq(&pprt_lock)) {
+			phys_scan_contacts();
+
+			/* no need for the parport anymore */
+			spin_unlock_irq(&pprt_lock);
+		}
+
+		if (!inputs_stable || phys_curr != phys_prev)
+			panel_process_inputs();
+	}
+
+	if (keypressed && lcd.enabled && lcd.initialized)
+		charlcd_poke(lcd.charlcd);
+
+	mod_timer(&scan_timer, jiffies + INPUT_POLL_TIME);
+}
+
+static void init_scan_timer(void)
+{
+	if (scan_timer.function)
+		return;		/* already started */
+
+	timer_setup(&scan_timer, panel_scan_timer, 0);
+	scan_timer.expires = jiffies + INPUT_POLL_TIME;
+	add_timer(&scan_timer);
+}
+
+/* converts a name of the form "({BbAaPpSsEe}{01234567-})*" to a series of bits.
+ * if <omask> or <imask> are non-null, they will be or'ed with the bits
+ * corresponding to out and in bits respectively.
+ * returns 1 if ok, 0 if error (in which case, nothing is written).
+ */
+static u8 input_name2mask(const char *name, __u64 *mask, __u64 *value,
+			  u8 *imask, u8 *omask)
+{
+	const char sigtab[] = "EeSsPpAaBb";
+	u8 im, om;
+	__u64 m, v;
+
+	om = 0;
+	im = 0;
+	m = 0ULL;
+	v = 0ULL;
+	while (*name) {
+		int in, out, bit, neg;
+		const char *idx;
+
+		idx = strchr(sigtab, *name);
+		if (!idx)
+			return 0;	/* input name not found */
+
+		in = idx - sigtab;
+		neg = (in & 1);	/* odd (lower) names are negated */
+		in >>= 1;
+		im |= BIT(in);
+
+		name++;
+		if (*name >= '0' && *name <= '7') {
+			out = *name - '0';
+			om |= BIT(out);
+		} else if (*name == '-') {
+			out = 8;
+		} else {
+			return 0;	/* unknown bit name */
+		}
+
+		bit = (out * 5) + in;
+
+		m |= 1ULL << bit;
+		if (!neg)
+			v |= 1ULL << bit;
+		name++;
+	}
+	*mask = m;
+	*value = v;
+	if (imask)
+		*imask |= im;
+	if (omask)
+		*omask |= om;
+	return 1;
+}
+
+/* tries to bind a key to the signal name <name>. The key will send the
+ * strings <press>, <repeat>, <release> for these respective events.
+ * Returns the pointer to the new key if ok, NULL if the key could not be bound.
+ */
+static struct logical_input *panel_bind_key(const char *name, const char *press,
+					    const char *repeat,
+					    const char *release)
+{
+	struct logical_input *key;
+
+	key = kzalloc(sizeof(*key), GFP_KERNEL);
+	if (!key)
+		return NULL;
+
+	if (!input_name2mask(name, &key->mask, &key->value, &scan_mask_i,
+			     &scan_mask_o)) {
+		kfree(key);
+		return NULL;
+	}
+
+	key->type = INPUT_TYPE_KBD;
+	key->state = INPUT_ST_LOW;
+	key->rise_time = 1;
+	key->fall_time = 1;
+
+	strncpy(key->u.kbd.press_str, press, sizeof(key->u.kbd.press_str));
+	strncpy(key->u.kbd.repeat_str, repeat, sizeof(key->u.kbd.repeat_str));
+	strncpy(key->u.kbd.release_str, release,
+		sizeof(key->u.kbd.release_str));
+	list_add(&key->list, &logical_inputs);
+	return key;
+}
+
+#if 0
+/* tries to bind a callback function to the signal name <name>. The function
+ * <press_fct> will be called with the <press_data> arg when the signal is
+ * activated, and so on for <release_fct>/<release_data>
+ * Returns the pointer to the new signal if ok, NULL if the signal could not
+ * be bound.
+ */
+static struct logical_input *panel_bind_callback(char *name,
+						 void (*press_fct)(int),
+						 int press_data,
+						 void (*release_fct)(int),
+						 int release_data)
+{
+	struct logical_input *callback;
+
+	callback = kmalloc(sizeof(*callback), GFP_KERNEL);
+	if (!callback)
+		return NULL;
+
+	memset(callback, 0, sizeof(struct logical_input));
+	if (!input_name2mask(name, &callback->mask, &callback->value,
+			     &scan_mask_i, &scan_mask_o))
+		return NULL;
+
+	callback->type = INPUT_TYPE_STD;
+	callback->state = INPUT_ST_LOW;
+	callback->rise_time = 1;
+	callback->fall_time = 1;
+	callback->u.std.press_fct = press_fct;
+	callback->u.std.press_data = press_data;
+	callback->u.std.release_fct = release_fct;
+	callback->u.std.release_data = release_data;
+	list_add(&callback->list, &logical_inputs);
+	return callback;
+}
+#endif
+
+static void keypad_init(void)
+{
+	int keynum;
+
+	init_waitqueue_head(&keypad_read_wait);
+	keypad_buflen = 0;	/* flushes any eventual noisy keystroke */
+
+	/* Let's create all known keys */
+
+	for (keynum = 0; keypad_profile[keynum][0][0]; keynum++) {
+		panel_bind_key(keypad_profile[keynum][0],
+			       keypad_profile[keynum][1],
+			       keypad_profile[keynum][2],
+			       keypad_profile[keynum][3]);
+	}
+
+	init_scan_timer();
+	keypad_initialized = 1;
+}
+
+/**************************************************/
+/* device initialization                          */
+/**************************************************/
+
+static void panel_attach(struct parport *port)
+{
+	struct pardev_cb panel_cb;
+
+	if (port->number != parport)
+		return;
+
+	if (pprt) {
+		pr_err("%s: port->number=%d parport=%d, already registered!\n",
+		       __func__, port->number, parport);
+		return;
+	}
+
+	memset(&panel_cb, 0, sizeof(panel_cb));
+	panel_cb.private = &pprt;
+	/* panel_cb.flags = 0 should be PARPORT_DEV_EXCL? */
+
+	pprt = parport_register_dev_model(port, "panel", &panel_cb, 0);
+	if (!pprt) {
+		pr_err("%s: port->number=%d parport=%d, parport_register_device() failed\n",
+		       __func__, port->number, parport);
+		return;
+	}
+
+	if (parport_claim(pprt)) {
+		pr_err("could not claim access to parport%d. Aborting.\n",
+		       parport);
+		goto err_unreg_device;
+	}
+
+	/* must init LCD first, just in case an IRQ from the keypad is
+	 * generated at keypad init
+	 */
+	if (lcd.enabled) {
+		lcd_init();
+		if (!lcd.charlcd || charlcd_register(lcd.charlcd))
+			goto err_unreg_device;
+	}
+
+	if (keypad.enabled) {
+		keypad_init();
+		if (misc_register(&keypad_dev))
+			goto err_lcd_unreg;
+	}
+	return;
+
+err_lcd_unreg:
+	if (scan_timer.function)
+		del_timer_sync(&scan_timer);
+	if (lcd.enabled)
+		charlcd_unregister(lcd.charlcd);
+err_unreg_device:
+	kfree(lcd.charlcd);
+	lcd.charlcd = NULL;
+	parport_unregister_device(pprt);
+	pprt = NULL;
+}
+
+static void panel_detach(struct parport *port)
+{
+	if (port->number != parport)
+		return;
+
+	if (!pprt) {
+		pr_err("%s: port->number=%d parport=%d, nothing to unregister.\n",
+		       __func__, port->number, parport);
+		return;
+	}
+	if (scan_timer.function)
+		del_timer_sync(&scan_timer);
+
+	if (keypad.enabled) {
+		misc_deregister(&keypad_dev);
+		keypad_initialized = 0;
+	}
+
+	if (lcd.enabled) {
+		charlcd_unregister(lcd.charlcd);
+		lcd.initialized = false;
+		kfree(lcd.charlcd->drvdata);
+		kfree(lcd.charlcd);
+		lcd.charlcd = NULL;
+	}
+
+	/* TODO: free all input signals */
+	parport_release(pprt);
+	parport_unregister_device(pprt);
+	pprt = NULL;
+}
+
+static struct parport_driver panel_driver = {
+	.name = "panel",
+	.match_port = panel_attach,
+	.detach = panel_detach,
+	.devmodel = true,
+};
+
+/* init function */
+static int __init panel_init_module(void)
+{
+	int selected_keypad_type = NOT_SET, err;
+
+	/* take care of an eventual profile */
+	switch (profile) {
+	case PANEL_PROFILE_CUSTOM:
+		/* custom profile */
+		selected_keypad_type = DEFAULT_KEYPAD_TYPE;
+		selected_lcd_type = DEFAULT_LCD_TYPE;
+		break;
+	case PANEL_PROFILE_OLD:
+		/* 8 bits, 2*16, old keypad */
+		selected_keypad_type = KEYPAD_TYPE_OLD;
+		selected_lcd_type = LCD_TYPE_OLD;
+
+		/* TODO: This two are a little hacky, sort it out later */
+		if (lcd_width == NOT_SET)
+			lcd_width = 16;
+		if (lcd_hwidth == NOT_SET)
+			lcd_hwidth = 16;
+		break;
+	case PANEL_PROFILE_NEW:
+		/* serial, 2*16, new keypad */
+		selected_keypad_type = KEYPAD_TYPE_NEW;
+		selected_lcd_type = LCD_TYPE_KS0074;
+		break;
+	case PANEL_PROFILE_HANTRONIX:
+		/* 8 bits, 2*16 hantronix-like, no keypad */
+		selected_keypad_type = KEYPAD_TYPE_NONE;
+		selected_lcd_type = LCD_TYPE_HANTRONIX;
+		break;
+	case PANEL_PROFILE_NEXCOM:
+		/* generic 8 bits, 2*16, nexcom keypad, eg. Nexcom. */
+		selected_keypad_type = KEYPAD_TYPE_NEXCOM;
+		selected_lcd_type = LCD_TYPE_NEXCOM;
+		break;
+	case PANEL_PROFILE_LARGE:
+		/* 8 bits, 2*40, old keypad */
+		selected_keypad_type = KEYPAD_TYPE_OLD;
+		selected_lcd_type = LCD_TYPE_OLD;
+		break;
+	}
+
+	/*
+	 * Overwrite selection with module param values (both keypad and lcd),
+	 * where the deprecated params have lower prio.
+	 */
+	if (keypad_enabled != NOT_SET)
+		selected_keypad_type = keypad_enabled;
+	if (keypad_type != NOT_SET)
+		selected_keypad_type = keypad_type;
+
+	keypad.enabled = (selected_keypad_type > 0);
+
+	if (lcd_enabled != NOT_SET)
+		selected_lcd_type = lcd_enabled;
+	if (lcd_type != NOT_SET)
+		selected_lcd_type = lcd_type;
+
+	lcd.enabled = (selected_lcd_type > 0);
+
+	if (lcd.enabled) {
+		/*
+		 * Init lcd struct with load-time values to preserve exact
+		 * current functionality (at least for now).
+		 */
+		lcd.charset = lcd_charset;
+		lcd.proto = lcd_proto;
+		lcd.pins.e = lcd_e_pin;
+		lcd.pins.rs = lcd_rs_pin;
+		lcd.pins.rw = lcd_rw_pin;
+		lcd.pins.cl = lcd_cl_pin;
+		lcd.pins.da = lcd_da_pin;
+		lcd.pins.bl = lcd_bl_pin;
+	}
+
+	switch (selected_keypad_type) {
+	case KEYPAD_TYPE_OLD:
+		keypad_profile = old_keypad_profile;
+		break;
+	case KEYPAD_TYPE_NEW:
+		keypad_profile = new_keypad_profile;
+		break;
+	case KEYPAD_TYPE_NEXCOM:
+		keypad_profile = nexcom_keypad_profile;
+		break;
+	default:
+		keypad_profile = NULL;
+		break;
+	}
+
+	if (!lcd.enabled && !keypad.enabled) {
+		/* no device enabled, let's exit */
+		pr_err("panel driver disabled.\n");
+		return -ENODEV;
+	}
+
+	err = parport_register_driver(&panel_driver);
+	if (err) {
+		pr_err("could not register with parport. Aborting.\n");
+		return err;
+	}
+
+	if (pprt)
+		pr_info("panel driver registered on parport%d (io=0x%lx).\n",
+			parport, pprt->port->base);
+	else
+		pr_info("panel driver not yet registered\n");
+	return 0;
+}
+
+static void __exit panel_cleanup_module(void)
+{
+	parport_unregister_driver(&panel_driver);
+}
+
+module_init(panel_init_module);
+module_exit(panel_cleanup_module);
+MODULE_AUTHOR("Willy Tarreau");
+MODULE_LICENSE("GPL");