Adding upstream version 6.1.76.upstream/6.1.76

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

1 files changed, 916 insertions, 0 deletions

diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c
new file mode 100644
index 000000000..dca1abe36
--- /dev/null
+++ b/drivers/tty/serial/8250/8250_exar.c
@@ -0,0 +1,916 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Probe module for 8250/16550-type Exar chips PCI serial ports.
+ *
+ *  Based on drivers/tty/serial/8250/8250_pci.c,
+ *
+ *  Copyright (C) 2017 Sudip Mukherjee, All Rights Reserved.
+ */
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/property.h>
+#include <linux/serial_core.h>
+#include <linux/serial_reg.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/tty.h>
+#include <linux/8250_pci.h>
+#include <linux/delay.h>
+
+#include <asm/byteorder.h>
+
+#include "8250.h"
+
+#define PCI_DEVICE_ID_ACCESSIO_COM_2S		0x1052
+#define PCI_DEVICE_ID_ACCESSIO_COM_4S		0x105d
+#define PCI_DEVICE_ID_ACCESSIO_COM_8S		0x106c
+#define PCI_DEVICE_ID_ACCESSIO_COM232_8		0x10a8
+#define PCI_DEVICE_ID_ACCESSIO_COM_2SM		0x10d2
+#define PCI_DEVICE_ID_ACCESSIO_COM_4SM		0x10db
+#define PCI_DEVICE_ID_ACCESSIO_COM_8SM		0x10ea
+
+#define PCI_DEVICE_ID_COMMTECH_4224PCI335	0x0002
+#define PCI_DEVICE_ID_COMMTECH_4222PCI335	0x0004
+#define PCI_DEVICE_ID_COMMTECH_2324PCI335	0x000a
+#define PCI_DEVICE_ID_COMMTECH_2328PCI335	0x000b
+#define PCI_DEVICE_ID_COMMTECH_4224PCIE		0x0020
+#define PCI_DEVICE_ID_COMMTECH_4228PCIE		0x0021
+#define PCI_DEVICE_ID_COMMTECH_4222PCIE		0x0022
+
+#define PCI_DEVICE_ID_EXAR_XR17V4358		0x4358
+#define PCI_DEVICE_ID_EXAR_XR17V8358		0x8358
+
+#define PCI_SUBDEVICE_ID_USR_2980		0x0128
+#define PCI_SUBDEVICE_ID_USR_2981		0x0129
+
+#define PCI_DEVICE_ID_SEALEVEL_710xC		0x1001
+#define PCI_DEVICE_ID_SEALEVEL_720xC		0x1002
+#define PCI_DEVICE_ID_SEALEVEL_740xC		0x1004
+#define PCI_DEVICE_ID_SEALEVEL_780xC		0x1008
+#define PCI_DEVICE_ID_SEALEVEL_716xC		0x1010
+
+#define UART_EXAR_INT0		0x80
+#define UART_EXAR_8XMODE	0x88	/* 8X sampling rate select */
+#define UART_EXAR_SLEEP		0x8b	/* Sleep mode */
+#define UART_EXAR_DVID		0x8d	/* Device identification */
+
+#define UART_EXAR_FCTR		0x08	/* Feature Control Register */
+#define UART_FCTR_EXAR_IRDA	0x10	/* IrDa data encode select */
+#define UART_FCTR_EXAR_485	0x20	/* Auto 485 half duplex dir ctl */
+#define UART_FCTR_EXAR_TRGA	0x00	/* FIFO trigger table A */
+#define UART_FCTR_EXAR_TRGB	0x60	/* FIFO trigger table B */
+#define UART_FCTR_EXAR_TRGC	0x80	/* FIFO trigger table C */
+#define UART_FCTR_EXAR_TRGD	0xc0	/* FIFO trigger table D programmable */
+
+#define UART_EXAR_TXTRG		0x0a	/* Tx FIFO trigger level write-only */
+#define UART_EXAR_RXTRG		0x0b	/* Rx FIFO trigger level write-only */
+
+#define UART_EXAR_MPIOINT_7_0	0x8f	/* MPIOINT[7:0] */
+#define UART_EXAR_MPIOLVL_7_0	0x90	/* MPIOLVL[7:0] */
+#define UART_EXAR_MPIO3T_7_0	0x91	/* MPIO3T[7:0] */
+#define UART_EXAR_MPIOINV_7_0	0x92	/* MPIOINV[7:0] */
+#define UART_EXAR_MPIOSEL_7_0	0x93	/* MPIOSEL[7:0] */
+#define UART_EXAR_MPIOOD_7_0	0x94	/* MPIOOD[7:0] */
+#define UART_EXAR_MPIOINT_15_8	0x95	/* MPIOINT[15:8] */
+#define UART_EXAR_MPIOLVL_15_8	0x96	/* MPIOLVL[15:8] */
+#define UART_EXAR_MPIO3T_15_8	0x97	/* MPIO3T[15:8] */
+#define UART_EXAR_MPIOINV_15_8	0x98	/* MPIOINV[15:8] */
+#define UART_EXAR_MPIOSEL_15_8	0x99	/* MPIOSEL[15:8] */
+#define UART_EXAR_MPIOOD_15_8	0x9a	/* MPIOOD[15:8] */
+
+#define UART_EXAR_RS485_DLY(x)	((x) << 4)
+
+/*
+ * IOT2040 MPIO wiring semantics:
+ *
+ * MPIO		Port	Function
+ * ----		----	--------
+ * 0		2 	Mode bit 0
+ * 1		2	Mode bit 1
+ * 2		2	Terminate bus
+ * 3		-	<reserved>
+ * 4		3	Mode bit 0
+ * 5		3	Mode bit 1
+ * 6		3	Terminate bus
+ * 7		-	<reserved>
+ * 8		2	Enable
+ * 9		3	Enable
+ * 10		-	Red LED
+ * 11..15	-	<unused>
+ */
+
+/* IOT2040 MPIOs 0..7 */
+#define IOT2040_UART_MODE_RS232		0x01
+#define IOT2040_UART_MODE_RS485		0x02
+#define IOT2040_UART_MODE_RS422		0x03
+#define IOT2040_UART_TERMINATE_BUS	0x04
+
+#define IOT2040_UART1_MASK		0x0f
+#define IOT2040_UART2_SHIFT		4
+
+#define IOT2040_UARTS_DEFAULT_MODE	0x11	/* both RS232 */
+#define IOT2040_UARTS_GPIO_LO_MODE	0x88	/* reserved pins as input */
+
+/* IOT2040 MPIOs 8..15 */
+#define IOT2040_UARTS_ENABLE		0x03
+#define IOT2040_UARTS_GPIO_HI_MODE	0xF8	/* enable & LED as outputs */
+
+struct exar8250;
+
+struct exar8250_platform {
+	int (*rs485_config)(struct uart_port *port, struct ktermios *termios,
+			    struct serial_rs485 *rs485);
+	const struct serial_rs485 *rs485_supported;
+	int (*register_gpio)(struct pci_dev *, struct uart_8250_port *);
+	void (*unregister_gpio)(struct uart_8250_port *);
+};
+
+/**
+ * struct exar8250_board - board information
+ * @num_ports: number of serial ports
+ * @reg_shift: describes UART register mapping in PCI memory
+ * @setup: quirk run at ->probe() stage
+ * @exit: quirk run at ->remove() stage
+ */
+struct exar8250_board {
+	unsigned int num_ports;
+	unsigned int reg_shift;
+	int	(*setup)(struct exar8250 *, struct pci_dev *,
+			 struct uart_8250_port *, int);
+	void	(*exit)(struct pci_dev *pcidev);
+};
+
+struct exar8250 {
+	unsigned int		nr;
+	struct exar8250_board	*board;
+	void __iomem		*virt;
+	int			line[];
+};
+
+static void exar_pm(struct uart_port *port, unsigned int state, unsigned int old)
+{
+	/*
+	 * Exar UARTs have a SLEEP register that enables or disables each UART
+	 * to enter sleep mode separately. On the XR17V35x the register
+	 * is accessible to each UART at the UART_EXAR_SLEEP offset, but
+	 * the UART channel may only write to the corresponding bit.
+	 */
+	serial_port_out(port, UART_EXAR_SLEEP, state ? 0xff : 0);
+}
+
+/*
+ * XR17V35x UARTs have an extra fractional divisor register (DLD)
+ * Calculate divisor with extra 4-bit fractional portion
+ */
+static unsigned int xr17v35x_get_divisor(struct uart_port *p, unsigned int baud,
+					 unsigned int *frac)
+{
+	unsigned int quot_16;
+
+	quot_16 = DIV_ROUND_CLOSEST(p->uartclk, baud);
+	*frac = quot_16 & 0x0f;
+
+	return quot_16 >> 4;
+}
+
+static void xr17v35x_set_divisor(struct uart_port *p, unsigned int baud,
+				 unsigned int quot, unsigned int quot_frac)
+{
+	serial8250_do_set_divisor(p, baud, quot, quot_frac);
+
+	/* Preserve bits not related to baudrate; DLD[7:4]. */
+	quot_frac |= serial_port_in(p, 0x2) & 0xf0;
+	serial_port_out(p, 0x2, quot_frac);
+}
+
+static int xr17v35x_startup(struct uart_port *port)
+{
+	/*
+	 * First enable access to IER [7:5], ISR [5:4], FCR [5:4],
+	 * MCR [7:5] and MSR [7:0]
+	 */
+	serial_port_out(port, UART_XR_EFR, UART_EFR_ECB);
+
+	/*
+	 * Make sure all interrups are masked until initialization is
+	 * complete and the FIFOs are cleared
+	 */
+	serial_port_out(port, UART_IER, 0);
+
+	return serial8250_do_startup(port);
+}
+
+static void exar_shutdown(struct uart_port *port)
+{
+	bool tx_complete = false;
+	struct uart_8250_port *up = up_to_u8250p(port);
+	struct circ_buf *xmit = &port->state->xmit;
+	int i = 0;
+	u16 lsr;
+
+	do {
+		lsr = serial_in(up, UART_LSR);
+		if (lsr & (UART_LSR_TEMT | UART_LSR_THRE))
+			tx_complete = true;
+		else
+			tx_complete = false;
+		usleep_range(1000, 1100);
+	} while (!uart_circ_empty(xmit) && !tx_complete && i++ < 1000);
+
+	serial8250_do_shutdown(port);
+}
+
+static int default_setup(struct exar8250 *priv, struct pci_dev *pcidev,
+			 int idx, unsigned int offset,
+			 struct uart_8250_port *port)
+{
+	const struct exar8250_board *board = priv->board;
+	unsigned int bar = 0;
+	unsigned char status;
+
+	port->port.iotype = UPIO_MEM;
+	port->port.mapbase = pci_resource_start(pcidev, bar) + offset;
+	port->port.membase = priv->virt + offset;
+	port->port.regshift = board->reg_shift;
+
+	/*
+	 * XR17V35x UARTs have an extra divisor register, DLD that gets enabled
+	 * with when DLAB is set which will cause the device to incorrectly match
+	 * and assign port type to PORT_16650. The EFR for this UART is found
+	 * at offset 0x09. Instead check the Deice ID (DVID) register
+	 * for a 2, 4 or 8 port UART.
+	 */
+	status = readb(port->port.membase + UART_EXAR_DVID);
+	if (status == 0x82 || status == 0x84 || status == 0x88) {
+		port->port.type = PORT_XR17V35X;
+
+		port->port.get_divisor = xr17v35x_get_divisor;
+		port->port.set_divisor = xr17v35x_set_divisor;
+
+		port->port.startup = xr17v35x_startup;
+	} else {
+		port->port.type = PORT_XR17D15X;
+	}
+
+	port->port.pm = exar_pm;
+	port->port.shutdown = exar_shutdown;
+
+	return 0;
+}
+
+static int
+pci_fastcom335_setup(struct exar8250 *priv, struct pci_dev *pcidev,
+		     struct uart_8250_port *port, int idx)
+{
+	unsigned int offset = idx * 0x200;
+	unsigned int baud = 1843200;
+	u8 __iomem *p;
+	int err;
+
+	port->port.uartclk = baud * 16;
+
+	err = default_setup(priv, pcidev, idx, offset, port);
+	if (err)
+		return err;
+
+	p = port->port.membase;
+
+	writeb(0x00, p + UART_EXAR_8XMODE);
+	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
+	writeb(32, p + UART_EXAR_TXTRG);
+	writeb(32, p + UART_EXAR_RXTRG);
+
+	/*
+	 * Setup Multipurpose Input/Output pins.
+	 */
+	if (idx == 0) {
+		switch (pcidev->device) {
+		case PCI_DEVICE_ID_COMMTECH_4222PCI335:
+		case PCI_DEVICE_ID_COMMTECH_4224PCI335:
+			writeb(0x78, p + UART_EXAR_MPIOLVL_7_0);
+			writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
+			writeb(0x00, p + UART_EXAR_MPIOSEL_7_0);
+			break;
+		case PCI_DEVICE_ID_COMMTECH_2324PCI335:
+		case PCI_DEVICE_ID_COMMTECH_2328PCI335:
+			writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
+			writeb(0xc0, p + UART_EXAR_MPIOINV_7_0);
+			writeb(0xc0, p + UART_EXAR_MPIOSEL_7_0);
+			break;
+		}
+		writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
+		writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
+		writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
+	}
+
+	return 0;
+}
+
+static int
+pci_connect_tech_setup(struct exar8250 *priv, struct pci_dev *pcidev,
+		       struct uart_8250_port *port, int idx)
+{
+	unsigned int offset = idx * 0x200;
+	unsigned int baud = 1843200;
+
+	port->port.uartclk = baud * 16;
+	return default_setup(priv, pcidev, idx, offset, port);
+}
+
+static int
+pci_xr17c154_setup(struct exar8250 *priv, struct pci_dev *pcidev,
+		   struct uart_8250_port *port, int idx)
+{
+	unsigned int offset = idx * 0x200;
+	unsigned int baud = 921600;
+
+	port->port.uartclk = baud * 16;
+	return default_setup(priv, pcidev, idx, offset, port);
+}
+
+static void setup_gpio(struct pci_dev *pcidev, u8 __iomem *p)
+{
+	/*
+	 * The Commtech adapters required the MPIOs to be driven low. The Exar
+	 * devices will export them as GPIOs, so we pre-configure them safely
+	 * as inputs.
+	 */
+
+	u8 dir = 0x00;
+
+	if  ((pcidev->vendor == PCI_VENDOR_ID_EXAR) &&
+		(pcidev->subsystem_vendor != PCI_VENDOR_ID_SEALEVEL)) {
+		// Configure GPIO as inputs for Commtech adapters
+		dir = 0xff;
+	} else {
+		// Configure GPIO as outputs for SeaLevel adapters
+		dir = 0x00;
+	}
+
+	writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
+	writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
+	writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
+	writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
+	writeb(dir,  p + UART_EXAR_MPIOSEL_7_0);
+	writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
+	writeb(0x00, p + UART_EXAR_MPIOINT_15_8);
+	writeb(0x00, p + UART_EXAR_MPIOLVL_15_8);
+	writeb(0x00, p + UART_EXAR_MPIO3T_15_8);
+	writeb(0x00, p + UART_EXAR_MPIOINV_15_8);
+	writeb(dir,  p + UART_EXAR_MPIOSEL_15_8);
+	writeb(0x00, p + UART_EXAR_MPIOOD_15_8);
+}
+
+static struct platform_device *__xr17v35x_register_gpio(struct pci_dev *pcidev,
+							const struct software_node *node)
+{
+	struct platform_device *pdev;
+
+	pdev = platform_device_alloc("gpio_exar", PLATFORM_DEVID_AUTO);
+	if (!pdev)
+		return NULL;
+
+	pdev->dev.parent = &pcidev->dev;
+	ACPI_COMPANION_SET(&pdev->dev, ACPI_COMPANION(&pcidev->dev));
+
+	if (device_add_software_node(&pdev->dev, node) < 0 ||
+	    platform_device_add(pdev) < 0) {
+		platform_device_put(pdev);
+		return NULL;
+	}
+
+	return pdev;
+}
+
+static void __xr17v35x_unregister_gpio(struct platform_device *pdev)
+{
+	device_remove_software_node(&pdev->dev);
+	platform_device_unregister(pdev);
+}
+
+static const struct property_entry exar_gpio_properties[] = {
+	PROPERTY_ENTRY_U32("exar,first-pin", 0),
+	PROPERTY_ENTRY_U32("ngpios", 16),
+	{ }
+};
+
+static const struct software_node exar_gpio_node = {
+	.properties = exar_gpio_properties,
+};
+
+static int xr17v35x_register_gpio(struct pci_dev *pcidev, struct uart_8250_port *port)
+{
+	if (pcidev->vendor == PCI_VENDOR_ID_EXAR)
+		port->port.private_data =
+			__xr17v35x_register_gpio(pcidev, &exar_gpio_node);
+
+	return 0;
+}
+
+static void xr17v35x_unregister_gpio(struct uart_8250_port *port)
+{
+	if (!port->port.private_data)
+		return;
+
+	__xr17v35x_unregister_gpio(port->port.private_data);
+	port->port.private_data = NULL;
+}
+
+static int generic_rs485_config(struct uart_port *port, struct ktermios *termios,
+				struct serial_rs485 *rs485)
+{
+	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
+	u8 __iomem *p = port->membase;
+	u8 value;
+
+	value = readb(p + UART_EXAR_FCTR);
+	if (is_rs485)
+		value |= UART_FCTR_EXAR_485;
+	else
+		value &= ~UART_FCTR_EXAR_485;
+
+	writeb(value, p + UART_EXAR_FCTR);
+
+	if (is_rs485)
+		writeb(UART_EXAR_RS485_DLY(4), p + UART_MSR);
+
+	return 0;
+}
+
+static const struct serial_rs485 generic_rs485_supported = {
+	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND,
+};
+
+static const struct exar8250_platform exar8250_default_platform = {
+	.register_gpio = xr17v35x_register_gpio,
+	.unregister_gpio = xr17v35x_unregister_gpio,
+	.rs485_config = generic_rs485_config,
+	.rs485_supported = &generic_rs485_supported,
+};
+
+static int iot2040_rs485_config(struct uart_port *port, struct ktermios *termios,
+				struct serial_rs485 *rs485)
+{
+	bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
+	u8 __iomem *p = port->membase;
+	u8 mask = IOT2040_UART1_MASK;
+	u8 mode, value;
+
+	if (is_rs485) {
+		if (rs485->flags & SER_RS485_RX_DURING_TX)
+			mode = IOT2040_UART_MODE_RS422;
+		else
+			mode = IOT2040_UART_MODE_RS485;
+
+		if (rs485->flags & SER_RS485_TERMINATE_BUS)
+			mode |= IOT2040_UART_TERMINATE_BUS;
+	} else {
+		mode = IOT2040_UART_MODE_RS232;
+	}
+
+	if (port->line == 3) {
+		mask <<= IOT2040_UART2_SHIFT;
+		mode <<= IOT2040_UART2_SHIFT;
+	}
+
+	value = readb(p + UART_EXAR_MPIOLVL_7_0);
+	value &= ~mask;
+	value |= mode;
+	writeb(value, p + UART_EXAR_MPIOLVL_7_0);
+
+	return generic_rs485_config(port, termios, rs485);
+}
+
+static const struct serial_rs485 iot2040_rs485_supported = {
+	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND |
+		 SER_RS485_RX_DURING_TX | SER_RS485_TERMINATE_BUS,
+};
+
+static const struct property_entry iot2040_gpio_properties[] = {
+	PROPERTY_ENTRY_U32("exar,first-pin", 10),
+	PROPERTY_ENTRY_U32("ngpios", 1),
+	{ }
+};
+
+static const struct software_node iot2040_gpio_node = {
+	.properties = iot2040_gpio_properties,
+};
+
+static int iot2040_register_gpio(struct pci_dev *pcidev,
+			      struct uart_8250_port *port)
+{
+	u8 __iomem *p = port->port.membase;
+
+	writeb(IOT2040_UARTS_DEFAULT_MODE, p + UART_EXAR_MPIOLVL_7_0);
+	writeb(IOT2040_UARTS_GPIO_LO_MODE, p + UART_EXAR_MPIOSEL_7_0);
+	writeb(IOT2040_UARTS_ENABLE, p + UART_EXAR_MPIOLVL_15_8);
+	writeb(IOT2040_UARTS_GPIO_HI_MODE, p + UART_EXAR_MPIOSEL_15_8);
+
+	port->port.private_data =
+		__xr17v35x_register_gpio(pcidev, &iot2040_gpio_node);
+
+	return 0;
+}
+
+static const struct exar8250_platform iot2040_platform = {
+	.rs485_config = iot2040_rs485_config,
+	.rs485_supported = &iot2040_rs485_supported,
+	.register_gpio = iot2040_register_gpio,
+	.unregister_gpio = xr17v35x_unregister_gpio,
+};
+
+/*
+ * For SIMATIC IOT2000, only IOT2040 and its variants have the Exar device,
+ * IOT2020 doesn't have. Therefore it is sufficient to match on the common
+ * board name after the device was found.
+ */
+static const struct dmi_system_id exar_platforms[] = {
+	{
+		.matches = {
+			DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
+		},
+		.driver_data = (void *)&iot2040_platform,
+	},
+	{}
+};
+
+static const struct exar8250_platform *exar_get_platform(void)
+{
+	const struct dmi_system_id *dmi_match;
+
+	dmi_match = dmi_first_match(exar_platforms);
+	if (dmi_match)
+		return dmi_match->driver_data;
+
+	return &exar8250_default_platform;
+}
+
+static int
+pci_xr17v35x_setup(struct exar8250 *priv, struct pci_dev *pcidev,
+		   struct uart_8250_port *port, int idx)
+{
+	const struct exar8250_platform *platform = exar_get_platform();
+	unsigned int offset = idx * 0x400;
+	unsigned int baud = 7812500;
+	u8 __iomem *p;
+	int ret;
+
+	port->port.uartclk = baud * 16;
+	port->port.rs485_config = platform->rs485_config;
+	port->port.rs485_supported = *(platform->rs485_supported);
+
+	/*
+	 * Setup the UART clock for the devices on expansion slot to
+	 * half the clock speed of the main chip (which is 125MHz)
+	 */
+	if (idx >= 8)
+		port->port.uartclk /= 2;
+
+	ret = default_setup(priv, pcidev, idx, offset, port);
+	if (ret)
+		return ret;
+
+	p = port->port.membase;
+
+	writeb(0x00, p + UART_EXAR_8XMODE);
+	writeb(UART_FCTR_EXAR_TRGD, p + UART_EXAR_FCTR);
+	writeb(128, p + UART_EXAR_TXTRG);
+	writeb(128, p + UART_EXAR_RXTRG);
+
+	if (idx == 0) {
+		/* Setup Multipurpose Input/Output pins. */
+		setup_gpio(pcidev, p);
+
+		ret = platform->register_gpio(pcidev, port);
+	}
+
+	return ret;
+}
+
+static void pci_xr17v35x_exit(struct pci_dev *pcidev)
+{
+	const struct exar8250_platform *platform = exar_get_platform();
+	struct exar8250 *priv = pci_get_drvdata(pcidev);
+	struct uart_8250_port *port = serial8250_get_port(priv->line[0]);
+
+	platform->unregister_gpio(port);
+}
+
+static inline void exar_misc_clear(struct exar8250 *priv)
+{
+	/* Clear all PCI interrupts by reading INT0. No effect on IIR */
+	readb(priv->virt + UART_EXAR_INT0);
+
+	/* Clear INT0 for Expansion Interface slave ports, too */
+	if (priv->board->num_ports > 8)
+		readb(priv->virt + 0x2000 + UART_EXAR_INT0);
+}
+
+/*
+ * These Exar UARTs have an extra interrupt indicator that could fire for a
+ * few interrupts that are not presented/cleared through IIR.  One of which is
+ * a wakeup interrupt when coming out of sleep.  These interrupts are only
+ * cleared by reading global INT0 or INT1 registers as interrupts are
+ * associated with channel 0. The INT[3:0] registers _are_ accessible from each
+ * channel's address space, but for the sake of bus efficiency we register a
+ * dedicated handler at the PCI device level to handle them.
+ */
+static irqreturn_t exar_misc_handler(int irq, void *data)
+{
+	exar_misc_clear(data);
+
+	return IRQ_HANDLED;
+}
+
+static int
+exar_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *ent)
+{
+	unsigned int nr_ports, i, bar = 0, maxnr;
+	struct exar8250_board *board;
+	struct uart_8250_port uart;
+	struct exar8250 *priv;
+	int rc;
+
+	board = (struct exar8250_board *)ent->driver_data;
+	if (!board)
+		return -EINVAL;
+
+	rc = pcim_enable_device(pcidev);
+	if (rc)
+		return rc;
+
+	maxnr = pci_resource_len(pcidev, bar) >> (board->reg_shift + 3);
+
+	if (pcidev->vendor == PCI_VENDOR_ID_ACCESSIO)
+		nr_ports = BIT(((pcidev->device & 0x38) >> 3) - 1);
+	else if (board->num_ports)
+		nr_ports = board->num_ports;
+	else if (pcidev->vendor == PCI_VENDOR_ID_SEALEVEL)
+		nr_ports = pcidev->device & 0xff;
+	else
+		nr_ports = pcidev->device & 0x0f;
+
+	priv = devm_kzalloc(&pcidev->dev, struct_size(priv, line, nr_ports), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->board = board;
+	priv->virt = pcim_iomap(pcidev, bar, 0);
+	if (!priv->virt)
+		return -ENOMEM;
+
+	pci_set_master(pcidev);
+
+	rc = pci_alloc_irq_vectors(pcidev, 1, 1, PCI_IRQ_ALL_TYPES);
+	if (rc < 0)
+		return rc;
+
+	memset(&uart, 0, sizeof(uart));
+	uart.port.flags = UPF_SHARE_IRQ | UPF_EXAR_EFR | UPF_FIXED_TYPE | UPF_FIXED_PORT;
+	uart.port.irq = pci_irq_vector(pcidev, 0);
+	uart.port.dev = &pcidev->dev;
+
+	rc = devm_request_irq(&pcidev->dev, uart.port.irq, exar_misc_handler,
+			 IRQF_SHARED, "exar_uart", priv);
+	if (rc)
+		return rc;
+
+	/* Clear interrupts */
+	exar_misc_clear(priv);
+
+	for (i = 0; i < nr_ports && i < maxnr; i++) {
+		rc = board->setup(priv, pcidev, &uart, i);
+		if (rc) {
+			dev_err(&pcidev->dev, "Failed to setup port %u\n", i);
+			break;
+		}
+
+		dev_dbg(&pcidev->dev, "Setup PCI port: port %lx, irq %d, type %d\n",
+			uart.port.iobase, uart.port.irq, uart.port.iotype);
+
+		priv->line[i] = serial8250_register_8250_port(&uart);
+		if (priv->line[i] < 0) {
+			dev_err(&pcidev->dev,
+				"Couldn't register serial port %lx, irq %d, type %d, error %d\n",
+				uart.port.iobase, uart.port.irq,
+				uart.port.iotype, priv->line[i]);
+			break;
+		}
+	}
+	priv->nr = i;
+	pci_set_drvdata(pcidev, priv);
+	return 0;
+}
+
+static void exar_pci_remove(struct pci_dev *pcidev)
+{
+	struct exar8250 *priv = pci_get_drvdata(pcidev);
+	unsigned int i;
+
+	for (i = 0; i < priv->nr; i++)
+		serial8250_unregister_port(priv->line[i]);
+
+	if (priv->board->exit)
+		priv->board->exit(pcidev);
+}
+
+static int __maybe_unused exar_suspend(struct device *dev)
+{
+	struct pci_dev *pcidev = to_pci_dev(dev);
+	struct exar8250 *priv = pci_get_drvdata(pcidev);
+	unsigned int i;
+
+	for (i = 0; i < priv->nr; i++)
+		if (priv->line[i] >= 0)
+			serial8250_suspend_port(priv->line[i]);
+
+	/* Ensure that every init quirk is properly torn down */
+	if (priv->board->exit)
+		priv->board->exit(pcidev);
+
+	return 0;
+}
+
+static int __maybe_unused exar_resume(struct device *dev)
+{
+	struct exar8250 *priv = dev_get_drvdata(dev);
+	unsigned int i;
+
+	exar_misc_clear(priv);
+
+	for (i = 0; i < priv->nr; i++)
+		if (priv->line[i] >= 0)
+			serial8250_resume_port(priv->line[i]);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(exar_pci_pm, exar_suspend, exar_resume);
+
+static const struct exar8250_board pbn_fastcom335_2 = {
+	.num_ports	= 2,
+	.setup		= pci_fastcom335_setup,
+};
+
+static const struct exar8250_board pbn_fastcom335_4 = {
+	.num_ports	= 4,
+	.setup		= pci_fastcom335_setup,
+};
+
+static const struct exar8250_board pbn_fastcom335_8 = {
+	.num_ports	= 8,
+	.setup		= pci_fastcom335_setup,
+};
+
+static const struct exar8250_board pbn_connect = {
+	.setup		= pci_connect_tech_setup,
+};
+
+static const struct exar8250_board pbn_exar_ibm_saturn = {
+	.num_ports	= 1,
+	.setup		= pci_xr17c154_setup,
+};
+
+static const struct exar8250_board pbn_exar_XR17C15x = {
+	.setup		= pci_xr17c154_setup,
+};
+
+static const struct exar8250_board pbn_exar_XR17V35x = {
+	.setup		= pci_xr17v35x_setup,
+	.exit		= pci_xr17v35x_exit,
+};
+
+static const struct exar8250_board pbn_fastcom35x_2 = {
+	.num_ports	= 2,
+	.setup		= pci_xr17v35x_setup,
+	.exit		= pci_xr17v35x_exit,
+};
+
+static const struct exar8250_board pbn_fastcom35x_4 = {
+	.num_ports	= 4,
+	.setup		= pci_xr17v35x_setup,
+	.exit		= pci_xr17v35x_exit,
+};
+
+static const struct exar8250_board pbn_fastcom35x_8 = {
+	.num_ports	= 8,
+	.setup		= pci_xr17v35x_setup,
+	.exit		= pci_xr17v35x_exit,
+};
+
+static const struct exar8250_board pbn_exar_XR17V4358 = {
+	.num_ports	= 12,
+	.setup		= pci_xr17v35x_setup,
+	.exit		= pci_xr17v35x_exit,
+};
+
+static const struct exar8250_board pbn_exar_XR17V8358 = {
+	.num_ports	= 16,
+	.setup		= pci_xr17v35x_setup,
+	.exit		= pci_xr17v35x_exit,
+};
+
+#define CONNECT_DEVICE(devid, sdevid, bd) {				\
+	PCI_DEVICE_SUB(							\
+		PCI_VENDOR_ID_EXAR,					\
+		PCI_DEVICE_ID_EXAR_##devid,				\
+		PCI_SUBVENDOR_ID_CONNECT_TECH,				\
+		PCI_SUBDEVICE_ID_CONNECT_TECH_PCI_##sdevid), 0, 0,	\
+		(kernel_ulong_t)&bd					\
+	}
+
+#define EXAR_DEVICE(vend, devid, bd) { PCI_DEVICE_DATA(vend, devid, &bd) }
+
+#define IBM_DEVICE(devid, sdevid, bd) {			\
+	PCI_DEVICE_SUB(					\
+		PCI_VENDOR_ID_EXAR,			\
+		PCI_DEVICE_ID_EXAR_##devid,		\
+		PCI_VENDOR_ID_IBM,			\
+		PCI_SUBDEVICE_ID_IBM_##sdevid), 0, 0,	\
+		(kernel_ulong_t)&bd			\
+	}
+
+#define USR_DEVICE(devid, sdevid, bd) {			\
+	PCI_DEVICE_SUB(					\
+		PCI_VENDOR_ID_USR,			\
+		PCI_DEVICE_ID_EXAR_##devid,		\
+		PCI_VENDOR_ID_EXAR,			\
+		PCI_SUBDEVICE_ID_USR_##sdevid), 0, 0,	\
+		(kernel_ulong_t)&bd			\
+	}
+
+static const struct pci_device_id exar_pci_tbl[] = {
+	EXAR_DEVICE(ACCESSIO, COM_2S, pbn_exar_XR17C15x),
+	EXAR_DEVICE(ACCESSIO, COM_4S, pbn_exar_XR17C15x),
+	EXAR_DEVICE(ACCESSIO, COM_8S, pbn_exar_XR17C15x),
+	EXAR_DEVICE(ACCESSIO, COM232_8, pbn_exar_XR17C15x),
+	EXAR_DEVICE(ACCESSIO, COM_2SM, pbn_exar_XR17C15x),
+	EXAR_DEVICE(ACCESSIO, COM_4SM, pbn_exar_XR17C15x),
+	EXAR_DEVICE(ACCESSIO, COM_8SM, pbn_exar_XR17C15x),
+
+	CONNECT_DEVICE(XR17C152, UART_2_232, pbn_connect),
+	CONNECT_DEVICE(XR17C154, UART_4_232, pbn_connect),
+	CONNECT_DEVICE(XR17C158, UART_8_232, pbn_connect),
+	CONNECT_DEVICE(XR17C152, UART_1_1, pbn_connect),
+	CONNECT_DEVICE(XR17C154, UART_2_2, pbn_connect),
+	CONNECT_DEVICE(XR17C158, UART_4_4, pbn_connect),
+	CONNECT_DEVICE(XR17C152, UART_2, pbn_connect),
+	CONNECT_DEVICE(XR17C154, UART_4, pbn_connect),
+	CONNECT_DEVICE(XR17C158, UART_8, pbn_connect),
+	CONNECT_DEVICE(XR17C152, UART_2_485, pbn_connect),
+	CONNECT_DEVICE(XR17C154, UART_4_485, pbn_connect),
+	CONNECT_DEVICE(XR17C158, UART_8_485, pbn_connect),
+
+	IBM_DEVICE(XR17C152, SATURN_SERIAL_ONE_PORT, pbn_exar_ibm_saturn),
+
+	/* USRobotics USR298x-OEM PCI Modems */
+	USR_DEVICE(XR17C152, 2980, pbn_exar_XR17C15x),
+	USR_DEVICE(XR17C152, 2981, pbn_exar_XR17C15x),
+
+	/* Exar Corp. XR17C15[248] Dual/Quad/Octal UART */
+	EXAR_DEVICE(EXAR, XR17C152, pbn_exar_XR17C15x),
+	EXAR_DEVICE(EXAR, XR17C154, pbn_exar_XR17C15x),
+	EXAR_DEVICE(EXAR, XR17C158, pbn_exar_XR17C15x),
+
+	/* Exar Corp. XR17V[48]35[248] Dual/Quad/Octal/Hexa PCIe UARTs */
+	EXAR_DEVICE(EXAR, XR17V352, pbn_exar_XR17V35x),
+	EXAR_DEVICE(EXAR, XR17V354, pbn_exar_XR17V35x),
+	EXAR_DEVICE(EXAR, XR17V358, pbn_exar_XR17V35x),
+	EXAR_DEVICE(EXAR, XR17V4358, pbn_exar_XR17V4358),
+	EXAR_DEVICE(EXAR, XR17V8358, pbn_exar_XR17V8358),
+	EXAR_DEVICE(COMMTECH, 4222PCIE, pbn_fastcom35x_2),
+	EXAR_DEVICE(COMMTECH, 4224PCIE, pbn_fastcom35x_4),
+	EXAR_DEVICE(COMMTECH, 4228PCIE, pbn_fastcom35x_8),
+
+	EXAR_DEVICE(COMMTECH, 4222PCI335, pbn_fastcom335_2),
+	EXAR_DEVICE(COMMTECH, 4224PCI335, pbn_fastcom335_4),
+	EXAR_DEVICE(COMMTECH, 2324PCI335, pbn_fastcom335_4),
+	EXAR_DEVICE(COMMTECH, 2328PCI335, pbn_fastcom335_8),
+
+	EXAR_DEVICE(SEALEVEL, 710xC, pbn_exar_XR17V35x),
+	EXAR_DEVICE(SEALEVEL, 720xC, pbn_exar_XR17V35x),
+	EXAR_DEVICE(SEALEVEL, 740xC, pbn_exar_XR17V35x),
+	EXAR_DEVICE(SEALEVEL, 780xC, pbn_exar_XR17V35x),
+	EXAR_DEVICE(SEALEVEL, 716xC, pbn_exar_XR17V35x),
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, exar_pci_tbl);
+
+static struct pci_driver exar_pci_driver = {
+	.name		= "exar_serial",
+	.probe		= exar_pci_probe,
+	.remove		= exar_pci_remove,
+	.driver         = {
+		.pm     = &exar_pci_pm,
+	},
+	.id_table	= exar_pci_tbl,
+};
+module_pci_driver(exar_pci_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Exar Serial Driver");
+MODULE_AUTHOR("Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>");