drivers/gpio/gpio-sch311x.c - kernel/msm-4.9 - Gitiles

 /*
  * GPIO driver for the SMSC SCH311x Super-I/O chips
  *
  * Copyright (C) 2013 Bruno Randolf <br1@einfach.org>
  *
  * SuperIO functions and chip detection:
  * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
 #include <linux/bitops.h>
 #include <linux/io.h>

 #define DRV_NAME			"gpio-sch311x"

 #define SCH311X_GPIO_CONF_OUT		0x00
 #define SCH311X_GPIO_CONF_IN		0x01
 #define SCH311X_GPIO_CONF_INVERT	0x02
 #define SCH311X_GPIO_CONF_OPEN_DRAIN	0x80

 #define SIO_CONFIG_KEY_ENTER		0x55
 #define SIO_CONFIG_KEY_EXIT		0xaa

 #define GP1				0x4b

 static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };

 static struct platform_device *sch311x_gpio_pdev;

 struct sch311x_pdev_data {		/* platform device data */
 	unsigned short runtime_reg;	/* runtime register base address */
 };

 struct sch311x_gpio_block {		/* one GPIO block runtime data */
 	struct gpio_chip chip;
 	unsigned short data_reg;	/* from definition below */
 	unsigned short *config_regs;	/* pointer to definition below */
 	unsigned short runtime_reg;	/* runtime register */
 	spinlock_t lock;		/* lock for this GPIO block */
 };

 struct sch311x_gpio_priv {		/* driver private data */
 	struct sch311x_gpio_block blocks[6];
 };

 struct sch311x_gpio_block_def {		/* register address definitions */
 	unsigned short data_reg;
 	unsigned short config_regs[8];
 	unsigned short base;
 };

 /* Note: some GPIOs are not available, these are marked with 0x00 */

 static struct sch311x_gpio_block_def sch311x_gpio_blocks[] = {
 	{
 		.data_reg = 0x4b,	/* GP1 */
 		.config_regs = {0x23, 0x24, 0x25, 0x26, 0x27, 0x29, 0x2a, 0x2b},
 		.base = 10,
 	},
 	{
 		.data_reg = 0x4c,	/* GP2 */
 		.config_regs = {0x00, 0x2c, 0x2d, 0x00, 0x00, 0x00, 0x00, 0x32},
 		.base = 20,
 	},
 	{
 		.data_reg = 0x4d,	/* GP3 */
 		.config_regs = {0x33, 0x34, 0x35, 0x36, 0x37, 0x00, 0x39, 0x3a},
 		.base = 30,
 	},
 	{
 		.data_reg = 0x4e,	/* GP4 */
 		.config_regs = {0x3b, 0x00, 0x3d, 0x00, 0x6e, 0x6f, 0x72, 0x73},
 		.base = 40,
 	},
 	{
 		.data_reg = 0x4f,	/* GP5 */
 		.config_regs = {0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46},
 		.base = 50,
 	},
 	{
 		.data_reg = 0x50,	/* GP6 */
 		.config_regs = {0x47, 0x48, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59},
 		.base = 60,
 	},
 };

 /*
  *	Super-IO functions
  */

 static inline int sch311x_sio_enter(int sio_config_port)
 {
 	/* Don't step on other drivers' I/O space by accident. */
 	if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
 		pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
 		       sio_config_port);
 		return -EBUSY;
 	}

 	outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
 	return 0;
 }

 static inline void sch311x_sio_exit(int sio_config_port)
 {
 	outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
 	release_region(sio_config_port, 2);
 }

 static inline int sch311x_sio_inb(int sio_config_port, int reg)
 {
 	outb(reg, sio_config_port);
 	return inb(sio_config_port + 1);
 }

 static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
 {
 	outb(reg, sio_config_port);
 	outb(val, sio_config_port + 1);
 }


 /*
  *	GPIO functions
  */

 static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
 {
 	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

 	if (block->config_regs[offset] == 0) /* GPIO is not available */
 		return -ENODEV;

 	if (!request_region(block->runtime_reg + block->config_regs[offset],
 			    1, DRV_NAME)) {
 		dev_err(chip->parent, "Failed to request region 0x%04x.\n",
 			block->runtime_reg + block->config_regs[offset]);
 		return -EBUSY;
 	}
 	return 0;
 }

 static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
 {
 	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

 	if (block->config_regs[offset] == 0) /* GPIO is not available */
 		return;

 	release_region(block->runtime_reg + block->config_regs[offset], 1);
 }

 static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
 	struct sch311x_gpio_block *block = gpiochip_get_data(chip);
 	unsigned char data;

 	spin_lock(&block->lock);
 	data = inb(block->runtime_reg + block->data_reg);
 	spin_unlock(&block->lock);

 	return !!(data & BIT(offset));
 }

 static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
 			       unsigned offset, int value)
 {
 	unsigned char data = inb(block->runtime_reg + block->data_reg);
 	if (value)
 		data |= BIT(offset);
 	else
 		data &= ~BIT(offset);
 	outb(data, block->runtime_reg + block->data_reg);
 }

 static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
 			     int value)
 {
 	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

 	spin_lock(&block->lock);
 	 __sch311x_gpio_set(block, offset, value);
 	spin_unlock(&block->lock);
 }

 static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 {
 	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

 	spin_lock(&block->lock);
 	outb(SCH311X_GPIO_CONF_IN, block->runtime_reg +
 	     block->config_regs[offset]);
 	spin_unlock(&block->lock);

 	return 0;
 }

 static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
 				      int value)
 {
 	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

 	spin_lock(&block->lock);

 	outb(SCH311X_GPIO_CONF_OUT, block->runtime_reg +
 	     block->config_regs[offset]);

 	__sch311x_gpio_set(block, offset, value);

 	spin_unlock(&block->lock);
 	return 0;
 }

 static int sch311x_gpio_probe(struct platform_device *pdev)
 {
 	struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
 	struct sch311x_gpio_priv *priv;
 	struct sch311x_gpio_block *block;
 	int err, i;

 	/* we can register all GPIO data registers at once */
 	if (!request_region(pdata->runtime_reg + GP1, 6, DRV_NAME)) {
 		dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
 			pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
 		return -EBUSY;
 	}

 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, priv);

 	for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
 		block = &priv->blocks[i];

 		spin_lock_init(&block->lock);

 		block->chip.label = DRV_NAME;
 		block->chip.owner = THIS_MODULE;
 		block->chip.request = sch311x_gpio_request;
 		block->chip.free = sch311x_gpio_free;
 		block->chip.direction_input = sch311x_gpio_direction_in;
 		block->chip.direction_output = sch311x_gpio_direction_out;
 		block->chip.get = sch311x_gpio_get;
 		block->chip.set = sch311x_gpio_set;
 		block->chip.ngpio = 8;
 		block->chip.parent = &pdev->dev;
 		block->chip.base = sch311x_gpio_blocks[i].base;
 		block->config_regs = sch311x_gpio_blocks[i].config_regs;
 		block->data_reg = sch311x_gpio_blocks[i].data_reg;
 		block->runtime_reg = pdata->runtime_reg;

 		err = gpiochip_add_data(&block->chip, block);
 		if (err < 0) {
 			dev_err(&pdev->dev,
 				"Could not register gpiochip, %d\n", err);
 			goto exit_err;
 		}
 		dev_info(&pdev->dev,
 			 "SMSC SCH311x GPIO block %d registered.\n", i);
 	}

 	return 0;

 exit_err:
 	release_region(pdata->runtime_reg + GP1, 6);
 	/* release already registered chips */
 	for (--i; i >= 0; i--)
 		gpiochip_remove(&priv->blocks[i].chip);
 	return err;
 }

 static int sch311x_gpio_remove(struct platform_device *pdev)
 {
 	struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
 	struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
 	int i;

 	release_region(pdata->runtime_reg + GP1, 6);

 	for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
 		gpiochip_remove(&priv->blocks[i].chip);
 		dev_info(&pdev->dev,
 			 "SMSC SCH311x GPIO block %d unregistered.\n", i);
 	}
 	return 0;
 }

 static struct platform_driver sch311x_gpio_driver = {
 	.driver.name	= DRV_NAME,
 	.driver.owner	= THIS_MODULE,
 	.probe		= sch311x_gpio_probe,
 	.remove		= sch311x_gpio_remove,
 };


 /*
  *	Init & exit routines
  */

 static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
 {
 	int err = 0, reg;
 	unsigned short base_addr;
 	unsigned char dev_id;

 	err = sch311x_sio_enter(sio_config_port);
 	if (err)
 		return err;

 	/* Check device ID. */
 	reg = sch311x_sio_inb(sio_config_port, 0x20);
 	switch (reg) {
 	case 0x7c: /* SCH3112 */
 		dev_id = 2;
 		break;
 	case 0x7d: /* SCH3114 */
 		dev_id = 4;
 		break;
 	case 0x7f: /* SCH3116 */
 		dev_id = 6;
 		break;
 	default:
 		err = -ENODEV;
 		goto exit;
 	}

 	/* Select logical device A (runtime registers) */
 	sch311x_sio_outb(sio_config_port, 0x07, 0x0a);

 	/* Check if Logical Device Register is currently active */
 	if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
 		pr_info("Seems that LDN 0x0a is not active...\n");

 	/* Get the base address of the runtime registers */
 	base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
 			   sch311x_sio_inb(sio_config_port, 0x61);
 	if (!base_addr) {
 		pr_err("Base address not set\n");
 		err = -ENODEV;
 		goto exit;
 	}
 	*addr = base_addr;

 	pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);

 exit:
 	sch311x_sio_exit(sio_config_port);
 	return err;
 }

 static int __init sch311x_gpio_pdev_add(const unsigned short addr)
 {
 	struct sch311x_pdev_data pdata;
 	int err;

 	pdata.runtime_reg = addr;

 	sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
 	if (!sch311x_gpio_pdev)
 		return -ENOMEM;

 	err = platform_device_add_data(sch311x_gpio_pdev,
 				       &pdata, sizeof(pdata));
 	if (err) {
 		pr_err(DRV_NAME "Platform data allocation failed\n");
 		goto err;
 	}

 	err = platform_device_add(sch311x_gpio_pdev);
 	if (err) {
 		pr_err(DRV_NAME "Device addition failed\n");
 		goto err;
 	}
 	return 0;

 err:
 	platform_device_put(sch311x_gpio_pdev);
 	return err;
 }

 static int __init sch311x_gpio_init(void)
 {
 	int err, i;
 	unsigned short addr = 0;

 	for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
 		if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
 			break;

 	if (!addr)
 		return -ENODEV;

 	err = platform_driver_register(&sch311x_gpio_driver);
 	if (err)
 		return err;

 	err = sch311x_gpio_pdev_add(addr);
 	if (err)
 		goto unreg_platform_driver;

 	return 0;

 unreg_platform_driver:
 	platform_driver_unregister(&sch311x_gpio_driver);
 	return err;
 }

 static void __exit sch311x_gpio_exit(void)
 {
 	platform_device_unregister(sch311x_gpio_pdev);
 	platform_driver_unregister(&sch311x_gpio_driver);
 }

 module_init(sch311x_gpio_init);
 module_exit(sch311x_gpio_exit);

 MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
 MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:gpio-sch311x");
	/*
	* GPIO driver for the SMSC SCH311x Super-I/O chips
	*
	* Copyright (C) 2013 Bruno Randolf <br1@einfach.org>
	*
	* SuperIO functions and chip detection:
	* (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/gpio.h>
	#include <linux/bitops.h>
	#include <linux/io.h>

	#define DRV_NAME "gpio-sch311x"

	#define SCH311X_GPIO_CONF_OUT 0x00
	#define SCH311X_GPIO_CONF_IN 0x01
	#define SCH311X_GPIO_CONF_INVERT 0x02
	#define SCH311X_GPIO_CONF_OPEN_DRAIN 0x80

	#define SIO_CONFIG_KEY_ENTER 0x55
	#define SIO_CONFIG_KEY_EXIT 0xaa

	#define GP1 0x4b

	static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };

	static struct platform_device *sch311x_gpio_pdev;

	struct sch311x_pdev_data { /* platform device data */
	unsigned short runtime_reg; /* runtime register base address */
	};

	struct sch311x_gpio_block { /* one GPIO block runtime data */
	struct gpio_chip chip;
	unsigned short data_reg; /* from definition below */
	unsigned short config_regs; / pointer to definition below */
	unsigned short runtime_reg; /* runtime register */
	spinlock_t lock; /* lock for this GPIO block */
	};

	struct sch311x_gpio_priv { /* driver private data */
	struct sch311x_gpio_block blocks[6];
	};

	struct sch311x_gpio_block_def { /* register address definitions */
	unsigned short data_reg;
	unsigned short config_regs[8];
	unsigned short base;
	};

	/* Note: some GPIOs are not available, these are marked with 0x00 */

	static struct sch311x_gpio_block_def sch311x_gpio_blocks[] = {
	{
	.data_reg = 0x4b, /* GP1 */
	.config_regs = {0x23, 0x24, 0x25, 0x26, 0x27, 0x29, 0x2a, 0x2b},
	.base = 10,
	},
	{
	.data_reg = 0x4c, /* GP2 */
	.config_regs = {0x00, 0x2c, 0x2d, 0x00, 0x00, 0x00, 0x00, 0x32},
	.base = 20,
	},
	{
	.data_reg = 0x4d, /* GP3 */
	.config_regs = {0x33, 0x34, 0x35, 0x36, 0x37, 0x00, 0x39, 0x3a},
	.base = 30,
	},
	{
	.data_reg = 0x4e, /* GP4 */
	.config_regs = {0x3b, 0x00, 0x3d, 0x00, 0x6e, 0x6f, 0x72, 0x73},
	.base = 40,
	},
	{
	.data_reg = 0x4f, /* GP5 */
	.config_regs = {0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46},
	.base = 50,
	},
	{
	.data_reg = 0x50, /* GP6 */
	.config_regs = {0x47, 0x48, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59},
	.base = 60,
	},
	};

	/*
	* Super-IO functions
	*/

	static inline int sch311x_sio_enter(int sio_config_port)
	{
	/* Don't step on other drivers' I/O space by accident. */
	if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
	pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
	sio_config_port);
	return -EBUSY;
	}

	outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
	return 0;
	}

	static inline void sch311x_sio_exit(int sio_config_port)
	{
	outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
	release_region(sio_config_port, 2);
	}

	static inline int sch311x_sio_inb(int sio_config_port, int reg)
	{
	outb(reg, sio_config_port);
	return inb(sio_config_port + 1);
	}

	static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
	{
	outb(reg, sio_config_port);
	outb(val, sio_config_port + 1);
	}


	/*
	* GPIO functions
	*/

	static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
	{
	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

	if (block->config_regs[offset] == 0) /* GPIO is not available */
	return -ENODEV;

	if (!request_region(block->runtime_reg + block->config_regs[offset],
	1, DRV_NAME)) {
	dev_err(chip->parent, "Failed to request region 0x%04x.\n",
	block->runtime_reg + block->config_regs[offset]);
	return -EBUSY;
	}
	return 0;
	}

	static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
	{
	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

	if (block->config_regs[offset] == 0) /* GPIO is not available */
	return;

	release_region(block->runtime_reg + block->config_regs[offset], 1);
	}

	static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
	{
	struct sch311x_gpio_block *block = gpiochip_get_data(chip);
	unsigned char data;

	spin_lock(&block->lock);
	data = inb(block->runtime_reg + block->data_reg);
	spin_unlock(&block->lock);

	return !!(data & BIT(offset));
	}

	static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
	unsigned offset, int value)
	{
	unsigned char data = inb(block->runtime_reg + block->data_reg);
	if (value)
	data \|= BIT(offset);
	else
	data &= ~BIT(offset);
	outb(data, block->runtime_reg + block->data_reg);
	}

	static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
	int value)
	{
	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

	spin_lock(&block->lock);
	__sch311x_gpio_set(block, offset, value);
	spin_unlock(&block->lock);
	}

	static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
	{
	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

	spin_lock(&block->lock);
	outb(SCH311X_GPIO_CONF_IN, block->runtime_reg +
	block->config_regs[offset]);
	spin_unlock(&block->lock);

	return 0;
	}

	static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
	int value)
	{
	struct sch311x_gpio_block *block = gpiochip_get_data(chip);

	spin_lock(&block->lock);

	outb(SCH311X_GPIO_CONF_OUT, block->runtime_reg +
	block->config_regs[offset]);

	__sch311x_gpio_set(block, offset, value);

	spin_unlock(&block->lock);
	return 0;
	}

	static int sch311x_gpio_probe(struct platform_device *pdev)
	{
	struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
	struct sch311x_gpio_priv *priv;
	struct sch311x_gpio_block *block;
	int err, i;

	/* we can register all GPIO data registers at once */
	if (!request_region(pdata->runtime_reg + GP1, 6, DRV_NAME)) {
	dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
	pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
	return -EBUSY;
	}

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	platform_set_drvdata(pdev, priv);

	for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
	block = &priv->blocks[i];

	spin_lock_init(&block->lock);

	block->chip.label = DRV_NAME;
	block->chip.owner = THIS_MODULE;
	block->chip.request = sch311x_gpio_request;
	block->chip.free = sch311x_gpio_free;
	block->chip.direction_input = sch311x_gpio_direction_in;
	block->chip.direction_output = sch311x_gpio_direction_out;
	block->chip.get = sch311x_gpio_get;
	block->chip.set = sch311x_gpio_set;
	block->chip.ngpio = 8;
	block->chip.parent = &pdev->dev;
	block->chip.base = sch311x_gpio_blocks[i].base;
	block->config_regs = sch311x_gpio_blocks[i].config_regs;
	block->data_reg = sch311x_gpio_blocks[i].data_reg;
	block->runtime_reg = pdata->runtime_reg;

	err = gpiochip_add_data(&block->chip, block);
	if (err < 0) {
	dev_err(&pdev->dev,
	"Could not register gpiochip, %d\n", err);
	goto exit_err;
	}
	dev_info(&pdev->dev,
	"SMSC SCH311x GPIO block %d registered.\n", i);
	}

	return 0;

	exit_err:
	release_region(pdata->runtime_reg + GP1, 6);
	/* release already registered chips */
	for (--i; i >= 0; i--)
	gpiochip_remove(&priv->blocks[i].chip);
	return err;
	}

	static int sch311x_gpio_remove(struct platform_device *pdev)
	{
	struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
	struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
	int i;

	release_region(pdata->runtime_reg + GP1, 6);

	for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
	gpiochip_remove(&priv->blocks[i].chip);
	dev_info(&pdev->dev,
	"SMSC SCH311x GPIO block %d unregistered.\n", i);
	}
	return 0;
	}

	static struct platform_driver sch311x_gpio_driver = {
	.driver.name = DRV_NAME,
	.driver.owner = THIS_MODULE,
	.probe = sch311x_gpio_probe,
	.remove = sch311x_gpio_remove,
	};


	/*
	* Init & exit routines
	*/

	static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
	{
	int err = 0, reg;
	unsigned short base_addr;
	unsigned char dev_id;

	err = sch311x_sio_enter(sio_config_port);
	if (err)
	return err;

	/* Check device ID. */
	reg = sch311x_sio_inb(sio_config_port, 0x20);
	switch (reg) {
	case 0x7c: /* SCH3112 */
	dev_id = 2;
	break;
	case 0x7d: /* SCH3114 */
	dev_id = 4;
	break;
	case 0x7f: /* SCH3116 */
	dev_id = 6;
	break;
	default:
	err = -ENODEV;
	goto exit;
	}

	/* Select logical device A (runtime registers) */
	sch311x_sio_outb(sio_config_port, 0x07, 0x0a);

	/* Check if Logical Device Register is currently active */
	if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
	pr_info("Seems that LDN 0x0a is not active...\n");

	/* Get the base address of the runtime registers */
	base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) \|
	sch311x_sio_inb(sio_config_port, 0x61);
	if (!base_addr) {
	pr_err("Base address not set\n");
	err = -ENODEV;
	goto exit;
	}
	*addr = base_addr;

	pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);

	exit:
	sch311x_sio_exit(sio_config_port);
	return err;
	}

	static int __init sch311x_gpio_pdev_add(const unsigned short addr)
	{
	struct sch311x_pdev_data pdata;
	int err;

	pdata.runtime_reg = addr;

	sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
	if (!sch311x_gpio_pdev)
	return -ENOMEM;

	err = platform_device_add_data(sch311x_gpio_pdev,
	&pdata, sizeof(pdata));
	if (err) {
	pr_err(DRV_NAME "Platform data allocation failed\n");
	goto err;
	}

	err = platform_device_add(sch311x_gpio_pdev);
	if (err) {
	pr_err(DRV_NAME "Device addition failed\n");
	goto err;
	}
	return 0;

	err:
	platform_device_put(sch311x_gpio_pdev);
	return err;
	}

	static int __init sch311x_gpio_init(void)
	{
	int err, i;
	unsigned short addr = 0;

	for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
	if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
	break;

	if (!addr)
	return -ENODEV;

	err = platform_driver_register(&sch311x_gpio_driver);
	if (err)
	return err;

	err = sch311x_gpio_pdev_add(addr);
	if (err)
	goto unreg_platform_driver;

	return 0;

	unreg_platform_driver:
	platform_driver_unregister(&sch311x_gpio_driver);
	return err;
	}

	static void __exit sch311x_gpio_exit(void)
	{
	platform_device_unregister(sch311x_gpio_pdev);
	platform_driver_unregister(&sch311x_gpio_driver);
	}

	module_init(sch311x_gpio_init);
	module_exit(sch311x_gpio_exit);

	MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
	MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:gpio-sch311x");