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-rw-r--r--drivers/parisc/led.c555
1 files changed, 555 insertions, 0 deletions
diff --git a/drivers/parisc/led.c b/drivers/parisc/led.c
new file mode 100644
index 0000000000..1f75d24160
--- /dev/null
+++ b/drivers/parisc/led.c
@@ -0,0 +1,555 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Chassis LCD/LED driver for HP-PARISC workstations
+ *
+ * (c) Copyright 2000 Red Hat Software
+ * (c) Copyright 2000 Helge Deller <hdeller@redhat.com>
+ * (c) Copyright 2001 Randolph Chung <tausq@debian.org>
+ * (c) Copyright 2000-2023 Helge Deller <deller@gmx.de>
+ *
+ * The control of the LEDs and LCDs on PARISC machines has to be done
+ * completely in software.
+ *
+ * The LEDs can be configured at runtime in /sys/class/leds/
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/ioport.h>
+#include <linux/utsname.h>
+#include <linux/capability.h>
+#include <linux/delay.h>
+#include <linux/reboot.h>
+#include <linux/uaccess.h>
+#include <linux/leds.h>
+#include <linux/platform_device.h>
+
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/hardware.h>
+#include <asm/param.h> /* HZ */
+#include <asm/led.h>
+#include <asm/pdc.h>
+
+#define LED_HAS_LCD 1
+#define LED_HAS_LED 2
+
+static unsigned char led_type; /* bitmask of LED_HAS_XXX */
+static unsigned char lastleds; /* LED state from most recent update */
+static unsigned char lcd_new_text;
+static unsigned char lcd_text[20];
+static unsigned char lcd_text_default[20];
+static unsigned char lcd_no_led_support; /* KittyHawk doesn't support LED on its LCD */
+
+struct lcd_block {
+ unsigned char command; /* stores the command byte */
+ unsigned char on; /* value for turning LED on */
+ unsigned char off; /* value for turning LED off */
+};
+
+/* Structure returned by PDC_RETURN_CHASSIS_INFO */
+/* NOTE: we use unsigned long:16 two times, since the following member
+ lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */
+struct pdc_chassis_lcd_info_ret_block {
+ unsigned long model:16; /* DISPLAY_MODEL_XXXX */
+ unsigned long lcd_width:16; /* width of the LCD in chars (DISPLAY_MODEL_LCD only) */
+ unsigned long lcd_cmd_reg_addr; /* ptr to LCD cmd-register & data ptr for LED */
+ unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */
+ unsigned int min_cmd_delay; /* delay in uS after cmd-write (LCD only) */
+ unsigned char reset_cmd1; /* command #1 for writing LCD string (LCD only) */
+ unsigned char reset_cmd2; /* command #2 for writing LCD string (LCD only) */
+ unsigned char act_enable; /* 0 = no activity (LCD only) */
+ struct lcd_block heartbeat;
+ struct lcd_block disk_io;
+ struct lcd_block lan_rcv;
+ struct lcd_block lan_tx;
+ char _pad;
+};
+
+
+/* LCD_CMD and LCD_DATA for KittyHawk machines */
+#define KITTYHAWK_LCD_CMD F_EXTEND(0xf0190000UL)
+#define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD + 1)
+
+/* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's
+ * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */
+static struct pdc_chassis_lcd_info_ret_block
+lcd_info __attribute__((aligned(8))) =
+{
+ .model = DISPLAY_MODEL_NONE,
+ .lcd_width = 16,
+ .lcd_cmd_reg_addr = KITTYHAWK_LCD_CMD,
+ .lcd_data_reg_addr = KITTYHAWK_LCD_DATA,
+ .min_cmd_delay = 80,
+ .reset_cmd1 = 0x80,
+ .reset_cmd2 = 0xc0,
+};
+
+/* direct access to some of the lcd_info variables */
+#define LCD_CMD_REG lcd_info.lcd_cmd_reg_addr
+#define LCD_DATA_REG lcd_info.lcd_data_reg_addr
+#define LED_DATA_REG lcd_info.lcd_cmd_reg_addr /* LASI & ASP only */
+
+/* ptr to LCD/LED-specific function */
+static void (*led_func_ptr) (unsigned char);
+
+
+static void lcd_print_now(void)
+{
+ int i;
+ char *str = lcd_text;
+
+ if (lcd_info.model != DISPLAY_MODEL_LCD)
+ return;
+
+ if (!lcd_new_text)
+ return;
+ lcd_new_text = 0;
+
+ /* Set LCD Cursor to 1st character */
+ gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
+ udelay(lcd_info.min_cmd_delay);
+
+ /* Print the string */
+ for (i = 0; i < lcd_info.lcd_width; i++) {
+ gsc_writeb(*str ? *str++ : ' ', LCD_DATA_REG);
+ udelay(lcd_info.min_cmd_delay);
+ }
+}
+
+/**
+ * lcd_print()
+ *
+ * @str: string to show on the LCD. If NULL, print current string again.
+ *
+ * Displays the given string on the LCD-Display of newer machines.
+ */
+void lcd_print(const char *str)
+{
+ /* copy display string to buffer for procfs */
+ if (str)
+ strscpy(lcd_text, str, sizeof(lcd_text));
+ lcd_new_text = 1;
+
+ /* print now if LCD without any LEDs */
+ if (led_type == LED_HAS_LCD)
+ lcd_print_now();
+}
+
+#define LED_DATA 0x01 /* data to shift (0:on 1:off) */
+#define LED_STROBE 0x02 /* strobe to clock data */
+
+/**
+ * led_ASP_driver() - LED driver for the ASP controller chip
+ *
+ * @leds: bitmap representing the LED status
+ */
+static void led_ASP_driver(unsigned char leds)
+{
+ int i;
+
+ leds = ~leds;
+ for (i = 0; i < 8; i++) {
+ unsigned char value;
+ value = (leds & 0x80) >> 7;
+ gsc_writeb( value, LED_DATA_REG );
+ gsc_writeb( value | LED_STROBE, LED_DATA_REG );
+ leds <<= 1;
+ }
+}
+
+/**
+ * led_LASI_driver() - LED driver for the LASI controller chip
+ *
+ * @leds: bitmap representing the LED status
+ */
+static void led_LASI_driver(unsigned char leds)
+{
+ leds = ~leds;
+ gsc_writeb( leds, LED_DATA_REG );
+}
+
+/**
+ * led_LCD_driver() - LED & LCD driver for LCD chips
+ *
+ * @leds: bitmap representing the LED status
+ */
+static void led_LCD_driver(unsigned char leds)
+{
+ static const unsigned char mask[4] = {
+ LED_HEARTBEAT, LED_DISK_IO,
+ LED_LAN_RCV, LED_LAN_TX };
+
+ static struct lcd_block * const blockp[4] = {
+ &lcd_info.heartbeat,
+ &lcd_info.disk_io,
+ &lcd_info.lan_rcv,
+ &lcd_info.lan_tx
+ };
+ static unsigned char latest_leds;
+ int i;
+
+ for (i = 0; i < 4; ++i) {
+ if ((leds & mask[i]) == (latest_leds & mask[i]))
+ continue;
+
+ gsc_writeb( blockp[i]->command, LCD_CMD_REG );
+ udelay(lcd_info.min_cmd_delay);
+
+ gsc_writeb( leds & mask[i] ? blockp[i]->on :
+ blockp[i]->off, LCD_DATA_REG );
+ udelay(lcd_info.min_cmd_delay);
+ }
+ latest_leds = leds;
+
+ lcd_print_now();
+}
+
+
+/**
+ * lcd_system_halt()
+ *
+ * @nb: pointer to the notifier_block structure
+ * @event: the event (SYS_RESTART, SYS_HALT or SYS_POWER_OFF)
+ * @buf: pointer to a buffer (not used)
+ *
+ * Called by the reboot notifier chain at shutdown. Stops all
+ * LED/LCD activities.
+ */
+static int lcd_system_halt(struct notifier_block *nb, unsigned long event, void *buf)
+{
+ const char *txt;
+
+ switch (event) {
+ case SYS_RESTART: txt = "SYSTEM RESTART";
+ break;
+ case SYS_HALT: txt = "SYSTEM HALT";
+ break;
+ case SYS_POWER_OFF: txt = "SYSTEM POWER OFF";
+ break;
+ default: return NOTIFY_DONE;
+ }
+
+ lcd_print(txt);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block lcd_system_halt_notifier = {
+ .notifier_call = lcd_system_halt,
+};
+
+static void set_led(struct led_classdev *led_cdev, enum led_brightness brightness);
+
+struct hppa_led {
+ struct led_classdev led_cdev;
+ unsigned char led_bit;
+};
+#define to_hppa_led(d) container_of(d, struct hppa_led, led_cdev)
+
+typedef void (*set_handler)(struct led_classdev *, enum led_brightness);
+struct led_type {
+ const char *name;
+ set_handler handler;
+ const char *default_trigger;
+};
+
+#define NUM_LEDS_PER_BOARD 8
+struct hppa_drvdata {
+ struct hppa_led leds[NUM_LEDS_PER_BOARD];
+};
+
+static void set_led(struct led_classdev *led_cdev, enum led_brightness brightness)
+{
+ struct hppa_led *p = to_hppa_led(led_cdev);
+ unsigned char led_bit = p->led_bit;
+
+ if (brightness == LED_OFF)
+ lastleds &= ~led_bit;
+ else
+ lastleds |= led_bit;
+
+ if (led_func_ptr)
+ led_func_ptr(lastleds);
+}
+
+
+static int hppa_led_generic_probe(struct platform_device *pdev,
+ struct led_type *types)
+{
+ struct hppa_drvdata *p;
+ int i, err;
+
+ p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ for (i = 0; i < NUM_LEDS_PER_BOARD; i++) {
+ struct led_classdev *lp = &p->leds[i].led_cdev;
+
+ p->leds[i].led_bit = BIT(i);
+ lp->name = types[i].name;
+ lp->brightness = LED_FULL;
+ lp->brightness_set = types[i].handler;
+ lp->default_trigger = types[i].default_trigger;
+ err = led_classdev_register(&pdev->dev, lp);
+ if (err) {
+ dev_err(&pdev->dev, "Could not register %s LED\n",
+ lp->name);
+ for (i--; i >= 0; i--)
+ led_classdev_unregister(&p->leds[i].led_cdev);
+ return err;
+ }
+ }
+
+ platform_set_drvdata(pdev, p);
+
+ return 0;
+}
+
+static int platform_led_remove(struct platform_device *pdev)
+{
+ struct hppa_drvdata *p = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < NUM_LEDS_PER_BOARD; i++)
+ led_classdev_unregister(&p->leds[i].led_cdev);
+
+ return 0;
+}
+
+static struct led_type mainboard_led_types[NUM_LEDS_PER_BOARD] = {
+ {
+ .name = "platform-lan-tx",
+ .handler = set_led,
+ .default_trigger = "tx",
+ },
+ {
+ .name = "platform-lan-rx",
+ .handler = set_led,
+ .default_trigger = "rx",
+ },
+ {
+ .name = "platform-disk",
+ .handler = set_led,
+ .default_trigger = "disk-activity",
+ },
+ {
+ .name = "platform-heartbeat",
+ .handler = set_led,
+ .default_trigger = "heartbeat",
+ },
+ {
+ .name = "platform-LED4",
+ .handler = set_led,
+ .default_trigger = "panic",
+ },
+ {
+ .name = "platform-LED5",
+ .handler = set_led,
+ .default_trigger = "panic",
+ },
+ {
+ .name = "platform-LED6",
+ .handler = set_led,
+ .default_trigger = "panic",
+ },
+ {
+ .name = "platform-LED7",
+ .handler = set_led,
+ .default_trigger = "panic",
+ },
+};
+
+static int platform_led_probe(struct platform_device *pdev)
+{
+ return hppa_led_generic_probe(pdev, mainboard_led_types);
+}
+
+MODULE_ALIAS("platform:platform-leds");
+
+static struct platform_driver hppa_mainboard_led_driver = {
+ .probe = platform_led_probe,
+ .remove = platform_led_remove,
+ .driver = {
+ .name = "platform-leds",
+ },
+};
+
+static struct platform_driver * const drivers[] = {
+ &hppa_mainboard_led_driver,
+};
+
+static struct platform_device platform_leds = {
+ .name = "platform-leds",
+};
+
+/**
+ * register_led_driver()
+ *
+ * @model: model type, one of the DISPLAY_MODEL_XXXX values
+ * @cmd_reg: physical address of cmd register for the LED/LCD
+ * @data_reg: physical address of data register for the LED/LCD
+ *
+ * Registers a chassis LED or LCD which should be driven by this driver.
+ * Only PDC-based, LASI- or ASP-style LEDs and LCDs are supported.
+ */
+int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg)
+{
+ if (led_func_ptr || !data_reg)
+ return 1;
+
+ /* No LEDs when running in QEMU */
+ if (running_on_qemu)
+ return 1;
+
+ lcd_info.model = model; /* store the values */
+ LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg;
+
+ switch (lcd_info.model) {
+ case DISPLAY_MODEL_LCD:
+ LCD_DATA_REG = data_reg;
+ pr_info("led: LCD display at %#lx and %#lx\n",
+ LCD_CMD_REG , LCD_DATA_REG);
+ led_func_ptr = led_LCD_driver;
+ if (lcd_no_led_support)
+ led_type = LED_HAS_LCD;
+ else
+ led_type = LED_HAS_LCD | LED_HAS_LED;
+ break;
+
+ case DISPLAY_MODEL_LASI:
+ LED_DATA_REG = data_reg;
+ led_func_ptr = led_LASI_driver;
+ pr_info("led: LED display at %#lx\n", LED_DATA_REG);
+ led_type = LED_HAS_LED;
+ break;
+
+ case DISPLAY_MODEL_OLD_ASP:
+ LED_DATA_REG = data_reg;
+ led_func_ptr = led_ASP_driver;
+ pr_info("led: LED (ASP-style) display at %#lx\n",
+ LED_DATA_REG);
+ led_type = LED_HAS_LED;
+ break;
+
+ default:
+ pr_err("led: Unknown LCD/LED model type %d\n", lcd_info.model);
+ return 1;
+ }
+
+ platform_register_drivers(drivers, ARRAY_SIZE(drivers));
+
+ return register_reboot_notifier(&lcd_system_halt_notifier);
+}
+
+/**
+ * early_led_init()
+ *
+ * early_led_init() is called early in the bootup-process and asks the
+ * PDC for an usable chassis LCD or LED. If the PDC doesn't return any
+ * info, then a LED might be detected by the LASI or ASP drivers later.
+ * KittyHawk machines have often a buggy PDC, so that we explicitly check
+ * for those machines here.
+ */
+static int __init early_led_init(void)
+{
+ struct pdc_chassis_info chassis_info;
+ int ret;
+
+ snprintf(lcd_text_default, sizeof(lcd_text_default),
+ "Linux %s", init_utsname()->release);
+ strcpy(lcd_text, lcd_text_default);
+ lcd_new_text = 1;
+
+ /* Work around the buggy PDC of KittyHawk-machines */
+ switch (CPU_HVERSION) {
+ case 0x580: /* KittyHawk DC2-100 (K100) */
+ case 0x581: /* KittyHawk DC3-120 (K210) */
+ case 0x582: /* KittyHawk DC3 100 (K400) */
+ case 0x583: /* KittyHawk DC3 120 (K410) */
+ case 0x58B: /* KittyHawk DC2 100 (K200) */
+ pr_info("LCD on KittyHawk-Machine found.\n");
+ lcd_info.model = DISPLAY_MODEL_LCD;
+ /* KittyHawk has no LED support on its LCD, so skip LED detection */
+ lcd_no_led_support = 1;
+ goto found; /* use the preinitialized values of lcd_info */
+ }
+
+ /* initialize the struct, so that we can check for valid return values */
+ chassis_info.actcnt = chassis_info.maxcnt = 0;
+
+ ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
+ if (ret != PDC_OK) {
+not_found:
+ lcd_info.model = DISPLAY_MODEL_NONE;
+ return 1;
+ }
+
+ /* check the results. Some machines have a buggy PDC */
+ if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
+ goto not_found;
+
+ switch (lcd_info.model) {
+ case DISPLAY_MODEL_LCD: /* LCD display */
+ if (chassis_info.actcnt <
+ offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
+ goto not_found;
+ if (!lcd_info.act_enable) {
+ /* PDC tells LCD should not be used. */
+ goto not_found;
+ }
+ break;
+
+ case DISPLAY_MODEL_NONE: /* no LED or LCD available */
+ goto not_found;
+
+ case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */
+ if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
+ goto not_found;
+ break;
+
+ default:
+ pr_warn("PDC reported unknown LCD/LED model %d\n",
+ lcd_info.model);
+ goto not_found;
+ }
+
+found:
+ /* register the LCD/LED driver */
+ return register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
+}
+arch_initcall(early_led_init);
+
+/**
+ * register_led_regions()
+ *
+ * Register_led_regions() registers the LCD/LED regions for /procfs.
+ * At bootup - where the initialisation of the LCD/LED often happens
+ * not all internal structures of request_region() are properly set up,
+ * so that we delay the led-registration until after busdevices_init()
+ * has been executed.
+ */
+static void __init register_led_regions(void)
+{
+ switch (lcd_info.model) {
+ case DISPLAY_MODEL_LCD:
+ request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd");
+ request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
+ break;
+ case DISPLAY_MODEL_LASI:
+ case DISPLAY_MODEL_OLD_ASP:
+ request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
+ break;
+ }
+}
+
+static int __init startup_leds(void)
+{
+ if (platform_device_register(&platform_leds))
+ printk(KERN_INFO "LED: failed to register LEDs\n");
+ register_led_regions();
+ return 0;
+}
+device_initcall(startup_leds);