drivers/gpio/gpio-wm831x.c - kernel/common.git - Git at Google

 /*
  * gpiolib support for Wolfson WM831x PMICs
  *
  * Copyright 2009 Wolfson Microelectronics PLC.
  *
  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  *
  *  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/kernel.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/gpio.h>
 #include <linux/mfd/core.h>
 #include <linux/platform_device.h>
 #include <linux/seq_file.h>

 #include <linux/mfd/wm831x/core.h>
 #include <linux/mfd/wm831x/pdata.h>
 #include <linux/mfd/wm831x/gpio.h>
 #include <linux/mfd/wm831x/irq.h>

 struct wm831x_gpio {
 	struct wm831x *wm831x;
 	struct gpio_chip gpio_chip;
 };

 static inline struct wm831x_gpio *to_wm831x_gpio(struct gpio_chip *chip)
 {
 	return container_of(chip, struct wm831x_gpio, gpio_chip);
 }

 static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 {
 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int val = WM831X_GPN_DIR;

 	if (wm831x->has_gpio_ena)
 		val |= WM831X_GPN_TRI;

 	return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
 			       WM831X_GPN_DIR | WM831X_GPN_TRI |
 			       WM831X_GPN_FN_MASK, val);
 }

 static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int ret;

 	ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL);
 	if (ret < 0)
 		return ret;

 	if (ret & 1 << offset)
 		return 1;
 	else
 		return 0;
 }

 static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;

 	wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,
 			value << offset);
 }

 static int wm831x_gpio_direction_out(struct gpio_chip *chip,
 				     unsigned offset, int value)
 {
 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int val = 0;
 	int ret;

 	if (wm831x->has_gpio_ena)
 		val |= WM831X_GPN_TRI;

 	ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
 			      WM831X_GPN_DIR | WM831X_GPN_TRI |
 			      WM831X_GPN_FN_MASK, val);
 	if (ret < 0)
 		return ret;

 	/* Can only set GPIO state once it's in output mode */
 	wm831x_gpio_set(chip, offset, value);

 	return 0;
 }

 static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;

 	return irq_create_mapping(wm831x->irq_domain,
 				  WM831X_IRQ_GPIO_1 + offset);
 }

 static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
 				    unsigned debounce)
 {
 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int reg = WM831X_GPIO1_CONTROL + offset;
 	int ret, fn;

 	ret = wm831x_reg_read(wm831x, reg);
 	if (ret < 0)
 		return ret;

 	switch (ret & WM831X_GPN_FN_MASK) {
 	case 0:
 	case 1:
 		break;
 	default:
 		/* Not in GPIO mode */
 		return -EBUSY;
 	}

 	if (debounce >= 32 && debounce <= 64)
 		fn = 0;
 	else if (debounce >= 4000 && debounce <= 8000)
 		fn = 1;
 	else
 		return -EINVAL;

 	return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
 }

 #ifdef CONFIG_DEBUG_FS
 static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 {
 	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
 	struct wm831x *wm831x = wm831x_gpio->wm831x;
 	int i, tristated;

 	for (i = 0; i < chip->ngpio; i++) {
 		int gpio = i + chip->base;
 		int reg;
 		const char *label, *pull, *powerdomain;

 		/* We report the GPIO even if it's not requested since
 		 * we're also reporting things like alternate
 		 * functions which apply even when the GPIO is not in
 		 * use as a GPIO.
 		 */
 		label = gpiochip_is_requested(chip, i);
 		if (!label)
 			label = "Unrequested";

 		seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);

 		reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i);
 		if (reg < 0) {
 			dev_err(wm831x->dev,
 				"GPIO control %d read failed: %d\n",
 				gpio, reg);
 			seq_printf(s, "\n");
 			continue;
 		}

 		switch (reg & WM831X_GPN_PULL_MASK) {
 		case WM831X_GPIO_PULL_NONE:
 			pull = "nopull";
 			break;
 		case WM831X_GPIO_PULL_DOWN:
 			pull = "pulldown";
 			break;
 		case WM831X_GPIO_PULL_UP:
 			pull = "pullup";
 			break;
 		default:
 			pull = "INVALID PULL";
 			break;
 		}

 		switch (i + 1) {
 		case 1 ... 3:
 		case 7 ... 9:
 			if (reg & WM831X_GPN_PWR_DOM)
 				powerdomain = "VPMIC";
 			else
 				powerdomain = "DBVDD";
 			break;

 		case 4 ... 6:
 		case 10 ... 12:
 			if (reg & WM831X_GPN_PWR_DOM)
 				powerdomain = "SYSVDD";
 			else
 				powerdomain = "DBVDD";
 			break;

 		case 13 ... 16:
 			powerdomain = "TPVDD";
 			break;

 		default:
 			BUG();
 			break;
 		}

 		tristated = reg & WM831X_GPN_TRI;
 		if (wm831x->has_gpio_ena)
 			tristated = !tristated;

 		seq_printf(s, " %s %s %s %s%s\n"
 			   "                                  %s%s (0x%4x)\n",
 			   reg & WM831X_GPN_DIR ? "in" : "out",
 			   wm831x_gpio_get(chip, i) ? "high" : "low",
 			   pull,
 			   powerdomain,
 			   reg & WM831X_GPN_POL ? "" : " inverted",
 			   reg & WM831X_GPN_OD ? "open-drain" : "CMOS",
 			   tristated ? " tristated" : "",
 			   reg);
 	}
 }
 #else
 #define wm831x_gpio_dbg_show NULL
 #endif

 static struct gpio_chip template_chip = {
 	.label			= "wm831x",
 	.owner			= THIS_MODULE,
 	.direction_input	= wm831x_gpio_direction_in,
 	.get			= wm831x_gpio_get,
 	.direction_output	= wm831x_gpio_direction_out,
 	.set			= wm831x_gpio_set,
 	.to_irq			= wm831x_gpio_to_irq,
 	.set_debounce		= wm831x_gpio_set_debounce,
 	.dbg_show		= wm831x_gpio_dbg_show,
 	.can_sleep		= true,
 };

 static int wm831x_gpio_probe(struct platform_device *pdev)
 {
 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
 	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
 	struct wm831x_gpio *wm831x_gpio;
 	int ret;

 	wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio),
 				   GFP_KERNEL);
 	if (wm831x_gpio == NULL)
 		return -ENOMEM;

 	wm831x_gpio->wm831x = wm831x;
 	wm831x_gpio->gpio_chip = template_chip;
 	wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio;
 	wm831x_gpio->gpio_chip.dev = &pdev->dev;
 	if (pdata && pdata->gpio_base)
 		wm831x_gpio->gpio_chip.base = pdata->gpio_base;
 	else
 		wm831x_gpio->gpio_chip.base = -1;

 	ret = gpiochip_add(&wm831x_gpio->gpio_chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
 		return ret;
 	}

 	platform_set_drvdata(pdev, wm831x_gpio);

 	return ret;
 }

 static int wm831x_gpio_remove(struct platform_device *pdev)
 {
 	struct wm831x_gpio *wm831x_gpio = platform_get_drvdata(pdev);

 	gpiochip_remove(&wm831x_gpio->gpio_chip);
 	return 0;
 }

 static struct platform_driver wm831x_gpio_driver = {
 	.driver.name	= "wm831x-gpio",
 	.driver.owner	= THIS_MODULE,
 	.probe		= wm831x_gpio_probe,
 	.remove		= wm831x_gpio_remove,
 };

 static int __init wm831x_gpio_init(void)
 {
 	return platform_driver_register(&wm831x_gpio_driver);
 }
 subsys_initcall(wm831x_gpio_init);

 static void __exit wm831x_gpio_exit(void)
 {
 	platform_driver_unregister(&wm831x_gpio_driver);
 }
 module_exit(wm831x_gpio_exit);

 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 MODULE_DESCRIPTION("GPIO interface for WM831x PMICs");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:wm831x-gpio");
	/*
	* gpiolib support for Wolfson WM831x PMICs
	*
	* Copyright 2009 Wolfson Microelectronics PLC.
	*
	* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
	*
	* 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/kernel.h>
	#include <linux/slab.h>
	#include <linux/module.h>
	#include <linux/gpio.h>
	#include <linux/mfd/core.h>
	#include <linux/platform_device.h>
	#include <linux/seq_file.h>

	#include <linux/mfd/wm831x/core.h>
	#include <linux/mfd/wm831x/pdata.h>
	#include <linux/mfd/wm831x/gpio.h>
	#include <linux/mfd/wm831x/irq.h>

	struct wm831x_gpio {
	struct wm831x *wm831x;
	struct gpio_chip gpio_chip;
	};

	static inline struct wm831x_gpio to_wm831x_gpio(struct gpio_chip chip)
	{
	return container_of(chip, struct wm831x_gpio, gpio_chip);
	}

	static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
	{
	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
	struct wm831x *wm831x = wm831x_gpio->wm831x;
	int val = WM831X_GPN_DIR;

	if (wm831x->has_gpio_ena)
	val \|= WM831X_GPN_TRI;

	return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
	WM831X_GPN_DIR \| WM831X_GPN_TRI \|
	WM831X_GPN_FN_MASK, val);
	}

	static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
	{
	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
	struct wm831x *wm831x = wm831x_gpio->wm831x;
	int ret;

	ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL);
	if (ret < 0)
	return ret;

	if (ret & 1 << offset)
	return 1;
	else
	return 0;
	}

	static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
	{
	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
	struct wm831x *wm831x = wm831x_gpio->wm831x;

	wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,
	value << offset);
	}

	static int wm831x_gpio_direction_out(struct gpio_chip *chip,
	unsigned offset, int value)
	{
	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
	struct wm831x *wm831x = wm831x_gpio->wm831x;
	int val = 0;
	int ret;

	if (wm831x->has_gpio_ena)
	val \|= WM831X_GPN_TRI;

	ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
	WM831X_GPN_DIR \| WM831X_GPN_TRI \|
	WM831X_GPN_FN_MASK, val);
	if (ret < 0)
	return ret;

	/* Can only set GPIO state once it's in output mode */
	wm831x_gpio_set(chip, offset, value);

	return 0;
	}

	static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
	{
	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
	struct wm831x *wm831x = wm831x_gpio->wm831x;

	return irq_create_mapping(wm831x->irq_domain,
	WM831X_IRQ_GPIO_1 + offset);
	}

	static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
	unsigned debounce)
	{
	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
	struct wm831x *wm831x = wm831x_gpio->wm831x;
	int reg = WM831X_GPIO1_CONTROL + offset;
	int ret, fn;

	ret = wm831x_reg_read(wm831x, reg);
	if (ret < 0)
	return ret;

	switch (ret & WM831X_GPN_FN_MASK) {
	case 0:
	case 1:
	break;
	default:
	/* Not in GPIO mode */
	return -EBUSY;
	}

	if (debounce >= 32 && debounce <= 64)
	fn = 0;
	else if (debounce >= 4000 && debounce <= 8000)
	fn = 1;
	else
	return -EINVAL;

	return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
	}

	#ifdef CONFIG_DEBUG_FS
	static void wm831x_gpio_dbg_show(struct seq_file s, struct gpio_chip chip)
	{
	struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
	struct wm831x *wm831x = wm831x_gpio->wm831x;
	int i, tristated;

	for (i = 0; i < chip->ngpio; i++) {
	int gpio = i + chip->base;
	int reg;
	const char label, pull, *powerdomain;

	/* We report the GPIO even if it's not requested since
	* we're also reporting things like alternate
	* functions which apply even when the GPIO is not in
	* use as a GPIO.
	*/
	label = gpiochip_is_requested(chip, i);
	if (!label)
	label = "Unrequested";

	seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);

	reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i);
	if (reg < 0) {
	dev_err(wm831x->dev,
	"GPIO control %d read failed: %d\n",
	gpio, reg);
	seq_printf(s, "\n");
	continue;
	}

	switch (reg & WM831X_GPN_PULL_MASK) {
	case WM831X_GPIO_PULL_NONE:
	pull = "nopull";
	break;
	case WM831X_GPIO_PULL_DOWN:
	pull = "pulldown";
	break;
	case WM831X_GPIO_PULL_UP:
	pull = "pullup";
	break;
	default:
	pull = "INVALID PULL";
	break;
	}

	switch (i + 1) {
	case 1 ... 3:
	case 7 ... 9:
	if (reg & WM831X_GPN_PWR_DOM)
	powerdomain = "VPMIC";
	else
	powerdomain = "DBVDD";
	break;

	case 4 ... 6:
	case 10 ... 12:
	if (reg & WM831X_GPN_PWR_DOM)
	powerdomain = "SYSVDD";
	else
	powerdomain = "DBVDD";
	break;

	case 13 ... 16:
	powerdomain = "TPVDD";
	break;

	default:
	BUG();
	break;
	}

	tristated = reg & WM831X_GPN_TRI;
	if (wm831x->has_gpio_ena)
	tristated = !tristated;

	seq_printf(s, " %s %s %s %s%s\n"
	" %s%s (0x%4x)\n",
	reg & WM831X_GPN_DIR ? "in" : "out",
	wm831x_gpio_get(chip, i) ? "high" : "low",
	pull,
	powerdomain,
	reg & WM831X_GPN_POL ? "" : " inverted",
	reg & WM831X_GPN_OD ? "open-drain" : "CMOS",
	tristated ? " tristated" : "",
	reg);
	}
	}
	#else
	#define wm831x_gpio_dbg_show NULL
	#endif

	static struct gpio_chip template_chip = {
	.label = "wm831x",
	.owner = THIS_MODULE,
	.direction_input = wm831x_gpio_direction_in,
	.get = wm831x_gpio_get,
	.direction_output = wm831x_gpio_direction_out,
	.set = wm831x_gpio_set,
	.to_irq = wm831x_gpio_to_irq,
	.set_debounce = wm831x_gpio_set_debounce,
	.dbg_show = wm831x_gpio_dbg_show,
	.can_sleep = true,
	};

	static int wm831x_gpio_probe(struct platform_device *pdev)
	{
	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
	struct wm831x_gpio *wm831x_gpio;
	int ret;

	wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio),
	GFP_KERNEL);
	if (wm831x_gpio == NULL)
	return -ENOMEM;

	wm831x_gpio->wm831x = wm831x;
	wm831x_gpio->gpio_chip = template_chip;
	wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio;
	wm831x_gpio->gpio_chip.dev = &pdev->dev;
	if (pdata && pdata->gpio_base)
	wm831x_gpio->gpio_chip.base = pdata->gpio_base;
	else
	wm831x_gpio->gpio_chip.base = -1;

	ret = gpiochip_add(&wm831x_gpio->gpio_chip);
	if (ret < 0) {
	dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
	return ret;
	}

	platform_set_drvdata(pdev, wm831x_gpio);

	return ret;
	}

	static int wm831x_gpio_remove(struct platform_device *pdev)
	{
	struct wm831x_gpio *wm831x_gpio = platform_get_drvdata(pdev);

	gpiochip_remove(&wm831x_gpio->gpio_chip);
	return 0;
	}

	static struct platform_driver wm831x_gpio_driver = {
	.driver.name = "wm831x-gpio",
	.driver.owner = THIS_MODULE,
	.probe = wm831x_gpio_probe,
	.remove = wm831x_gpio_remove,
	};

	static int __init wm831x_gpio_init(void)
	{
	return platform_driver_register(&wm831x_gpio_driver);
	}
	subsys_initcall(wm831x_gpio_init);

	static void __exit wm831x_gpio_exit(void)
	{
	platform_driver_unregister(&wm831x_gpio_driver);
	}
	module_exit(wm831x_gpio_exit);

	MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
	MODULE_DESCRIPTION("GPIO interface for WM831x PMICs");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:wm831x-gpio");