drivers/gpio/gpio-as3720.c - kernel/tegra - Git at Google

 /*
  * as3720-gpio.c  --  gpiolib support for ams AS3720 PMICs
  *
  * Copyright 2012 ams
  *
  * Author: Bernhard Breinbauer <bernhard.breinbauer@ams.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/slab.h>
 #include <linux/kernel.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/as3720.h>

 struct as3720_gpio {
 	struct as3720 *as3720;
 	struct gpio_chip gpio_chip;
 };

 static inline struct as3720_gpio *to_as3720_gpio(struct gpio_chip *chip)
 {
 	return container_of(chip, struct as3720_gpio, gpio_chip);
 }

 static int as3720_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 {
 	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
 	struct as3720 *as3720 = as3720_gpio->as3720;

 	return as3720_set_bits(as3720, AS3720_GPIO0_CONTROL_REG + offset,
 			       AS3720_GPIO_MODE_MASK,
 			       AS3720_GPIO_MODE_INPUT);
 }

 static int as3720_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
 	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
 	struct as3720 *as3720 = as3720_gpio->as3720;
 	int ret;
 	u32 val;

 	ret = as3720_reg_read(as3720, AS3720_GPIO_SIGNAL_IN_REG, &val);
 	if (ret < 0)
 		return ret;

 	if (val & (AS3720_GPIO1_SIGNAL_MASK << offset))
 		return 1;
 	else
 		return 0;
 }

 static int as3720_gpio_direction_out(struct gpio_chip *chip,
 				     unsigned offset, int value)
 {
 	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
 	struct as3720 *as3720 = as3720_gpio->as3720;

 	return as3720_set_bits(as3720, AS3720_GPIO0_CONTROL_REG + offset,
 			       AS3720_GPIO_MODE_MASK,
 			       AS3720_GPIO_MODE_OUTPUT_VDDH);
 }

 static void as3720_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
 	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
 	struct as3720 *as3720 = as3720_gpio->as3720;

 	as3720_set_bits(as3720, AS3720_GPIO_SIGNAL_OUT_REG, 1 << offset,
 			value << offset);
 }

 static int as3720_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
 	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
 	struct as3720 *as3720 = as3720_gpio->as3720;

 	if (!as3720->irq_base)
 		return -EINVAL;

 	return as3720->irq_base + AS3720_GPIO_IRQ_BASE + offset;
 }

 static int as3720_gpio_set_config(struct as3720_gpio *as3720_gpio,
 	struct as3720_gpio_config *gpio_cfg)
 {
 	int ret = 0;
 	u8 val = 0;
 	int gpio = gpio_cfg->gpio;
 	struct as3720 *as3720 = as3720_gpio->as3720;
 	if ((gpio < AS3720_GPIO0) || (gpio > AS3720_GPIO7))
 		return -EINVAL;

 	/* .invert + .iosf + .mode */
 	/* set up write of the GPIOX control register */
 	val = (gpio_cfg->iosf & AS3720_GPIO_IOSF_MASK) +
 		(gpio_cfg->mode & AS3720_GPIO_MODE_MASK);
 	if (gpio_cfg->invert)
 		val += (AS3720_GPIO_INV & AS3720_GPIO_INV_MASK);

 	ret = as3720_reg_write(as3720, AS3720_GPIO0_CONTROL_REG + gpio, val);
 	if (ret != 0) {
 		printk(KERN_INFO "AS3720_GPIO%d_CTRL_REG write err, ret: %d\n",
 			gpio, ret);
 		return ret;
 	}

 	/* if GPIO is configured as an output, set initial output state */
 	if ((gpio_cfg->mode == AS3720_GPIO_MODE_OUTPUT_VDDH) ||
 		(gpio_cfg->mode == AS3720_GPIO_MODE_OUTPUT_VDDL)) {
 		/*GPIO0 -> bit 0, ..., GPIO7 -> bit 7, output_state = 0 or 1*/
 		val = (gpio_cfg->output_state ^ gpio_cfg->invert) << gpio;
 		ret = as3720_set_bits(as3720, AS3720_GPIO_SIGNAL_OUT_REG,
 				1 << gpio, val);
 	}

 	return ret;
 }

 static int as3720_gpio_init_regs(struct as3720_gpio *as3720_gpio,
 		struct as3720_platform_data *pdata)
 {
 	int ret;
 	int i;
 	for (i = 0; i < pdata->num_gpio_cfgs; i++) {
 		ret = as3720_gpio_set_config(as3720_gpio,
 			&pdata->gpio_cfgs[i]);
 		if (ret < 0) {
 			dev_err(as3720_gpio->as3720->dev,
 				"Failed to set gpio config\n");
 			return ret;
 		}
 	}

 	return 0;
 }

 #ifdef CONFIG_DEBUG_FS
 static void as3720_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 {
 	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
 	struct as3720 *as3720 = as3720_gpio->as3720;
 	int i;

 	for (i = 0; i < chip->ngpio; i++) {
 		int gpio = i + chip->base;
 		u32 reg;
 		int ret;
 		const char *label, *pull, *direction;

 		/* 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);

 		ret = as3720_reg_read(as3720,
 			AS3720_GPIO0_CONTROL_REG + i, &reg);
 		if (ret < 0) {
 			dev_err(as3720->dev,
 				"GPIO control %d read failed: %d\n",
 				gpio, ret);
 			seq_printf(s, "\n");
 			continue;
 		}

 		switch (reg & AS3720_GPIO_MODE_MASK) {
 		case AS3720_GPIO_MODE_INPUT:
 			direction = "in";
 			pull = "nopull";
 			break;
 		case AS3720_GPIO_MODE_OUTPUT_VDDH:
 			direction = "out";
 			pull = "push and pull";
 			break;
 		case AS3720_GPIO_MODE_IO_OPEN_DRAIN:
 			direction = "io";
 			pull = "nopull";
 			break;
 		case AS3720_GPIO_MODE_INPUT_W_PULLUP:
 			direction = "in";
 			pull = "pullup";
 			break;
 		case AS3720_GPIO_MODE_INPUT_W_PULLDOWN:
 			direction = "in";
 			pull = "pulldown";
 			break;
 		case AS3720_GPIO_MODE_IO_OPEN_DRAIN_PULLUP:
 			direction = "io";
 			pull = "pullup";
 			break;
 		case AS3720_GPIO_MODE_OUTPUT_VDDL:
 			direction = "out";
 			pull = "push and pull";
 			break;
 		default:
 			direction = "INVALID DIRECTION/MODE";
 			pull = "INVALID PULL";
 			break;
 		}

 		seq_printf(s, " %s %s %s\n"
 			   "                                  %s (0x%4x)\n",
 			   direction,
 			   as3720_gpio_get(chip, i) ? "high" : "low",
 			   pull,
 			   reg & AS3720_GPIO_INV_MASK ? " inverted" : "",
 			   reg);
 	}
 }
 #else
 #define as3720_gpio_dbg_show NULL
 #endif

 static struct gpio_chip as3720_gpio_chip = {
 	.label			= "as3720",
 	.owner			= THIS_MODULE,
 	.direction_input	= as3720_gpio_direction_in,
 	.get			= as3720_gpio_get,
 	.direction_output	= as3720_gpio_direction_out,
 	.set			= as3720_gpio_set,
 	.to_irq			= as3720_gpio_to_irq,
 	.dbg_show		= as3720_gpio_dbg_show,
 	.can_sleep		= 1,
 };

 static int as3720_gpio_probe(struct platform_device *pdev)
 {
 	struct as3720 *as3720 =  dev_get_drvdata(pdev->dev.parent);
 	struct as3720_platform_data *pdata = dev_get_platdata(pdev->dev.parent);
 	struct as3720_gpio *as3720_gpio;
 	int ret;

 	as3720_gpio = devm_kzalloc(&pdev->dev,
 			sizeof(*as3720_gpio), GFP_KERNEL);
 	if (as3720_gpio == NULL) {
 		dev_err(&pdev->dev, "Memory allocaiton failure\n");
 		return -ENOMEM;
 	}

 	as3720_gpio->as3720 = as3720;
 	as3720_gpio->gpio_chip = as3720_gpio_chip;
 	as3720_gpio->gpio_chip.ngpio = AS3720_NUM_GPIO;
 	as3720_gpio->gpio_chip.dev = &pdev->dev;
 	if (pdata && pdata->gpio_base)
 		as3720_gpio->gpio_chip.base = pdata->gpio_base;
 	else
 		as3720_gpio->gpio_chip.base = -1;

 	platform_set_drvdata(pdev, as3720_gpio);

 	ret = as3720_gpio_init_regs(as3720_gpio, pdata);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "gpio_init_regs failed\n");
 		return ret;
 	}

 	ret = gpiochip_add(&as3720_gpio->gpio_chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
 			ret);
 		return ret;
 	}
 	return 0;
 }

 static int as3720_gpio_remove(struct platform_device *pdev)
 {
 	struct as3720_gpio *as3720_gpio = platform_get_drvdata(pdev);

 	return gpiochip_remove(&as3720_gpio->gpio_chip);
 }

 static struct platform_driver as3720_gpio_driver = {
 	.driver.name	= "as3720-gpio",
 	.driver.owner	= THIS_MODULE,
 	.probe		= as3720_gpio_probe,
 	.remove		= as3720_gpio_remove,
 };

 static int __init as3720_gpio_init(void)
 {
 	return platform_driver_register(&as3720_gpio_driver);
 }
 subsys_initcall(as3720_gpio_init);

 static void __exit as3720_gpio_exit(void)
 {
 	platform_driver_unregister(&as3720_gpio_driver);
 }
 module_exit(as3720_gpio_exit);

 MODULE_AUTHOR("Bernhard Breinbauer <bernhard.breinbauer@ams.com>");
 MODULE_DESCRIPTION("GPIO interface for AS3720 PMICs");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:as3720-gpio");
	/*
	* as3720-gpio.c -- gpiolib support for ams AS3720 PMICs
	*
	* Copyright 2012 ams
	*
	* Author: Bernhard Breinbauer <bernhard.breinbauer@ams.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/slab.h>
	#include <linux/kernel.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/as3720.h>

	struct as3720_gpio {
	struct as3720 *as3720;
	struct gpio_chip gpio_chip;
	};

	static inline struct as3720_gpio to_as3720_gpio(struct gpio_chip chip)
	{
	return container_of(chip, struct as3720_gpio, gpio_chip);
	}

	static int as3720_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
	{
	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
	struct as3720 *as3720 = as3720_gpio->as3720;

	return as3720_set_bits(as3720, AS3720_GPIO0_CONTROL_REG + offset,
	AS3720_GPIO_MODE_MASK,
	AS3720_GPIO_MODE_INPUT);
	}

	static int as3720_gpio_get(struct gpio_chip *chip, unsigned offset)
	{
	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
	struct as3720 *as3720 = as3720_gpio->as3720;
	int ret;
	u32 val;

	ret = as3720_reg_read(as3720, AS3720_GPIO_SIGNAL_IN_REG, &val);
	if (ret < 0)
	return ret;

	if (val & (AS3720_GPIO1_SIGNAL_MASK << offset))
	return 1;
	else
	return 0;
	}

	static int as3720_gpio_direction_out(struct gpio_chip *chip,
	unsigned offset, int value)
	{
	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
	struct as3720 *as3720 = as3720_gpio->as3720;

	return as3720_set_bits(as3720, AS3720_GPIO0_CONTROL_REG + offset,
	AS3720_GPIO_MODE_MASK,
	AS3720_GPIO_MODE_OUTPUT_VDDH);
	}

	static void as3720_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
	{
	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
	struct as3720 *as3720 = as3720_gpio->as3720;

	as3720_set_bits(as3720, AS3720_GPIO_SIGNAL_OUT_REG, 1 << offset,
	value << offset);
	}

	static int as3720_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
	{
	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
	struct as3720 *as3720 = as3720_gpio->as3720;

	if (!as3720->irq_base)
	return -EINVAL;

	return as3720->irq_base + AS3720_GPIO_IRQ_BASE + offset;
	}

	static int as3720_gpio_set_config(struct as3720_gpio *as3720_gpio,
	struct as3720_gpio_config *gpio_cfg)
	{
	int ret = 0;
	u8 val = 0;
	int gpio = gpio_cfg->gpio;
	struct as3720 *as3720 = as3720_gpio->as3720;
	if ((gpio < AS3720_GPIO0) \|\| (gpio > AS3720_GPIO7))
	return -EINVAL;

	/* .invert + .iosf + .mode */
	/* set up write of the GPIOX control register */
	val = (gpio_cfg->iosf & AS3720_GPIO_IOSF_MASK) +
	(gpio_cfg->mode & AS3720_GPIO_MODE_MASK);
	if (gpio_cfg->invert)
	val += (AS3720_GPIO_INV & AS3720_GPIO_INV_MASK);

	ret = as3720_reg_write(as3720, AS3720_GPIO0_CONTROL_REG + gpio, val);
	if (ret != 0) {
	printk(KERN_INFO "AS3720_GPIO%d_CTRL_REG write err, ret: %d\n",
	gpio, ret);
	return ret;
	}

	/* if GPIO is configured as an output, set initial output state */
	if ((gpio_cfg->mode == AS3720_GPIO_MODE_OUTPUT_VDDH) \|\|
	(gpio_cfg->mode == AS3720_GPIO_MODE_OUTPUT_VDDL)) {
	/GPIO0 -> bit 0, ..., GPIO7 -> bit 7, output_state = 0 or 1/
	val = (gpio_cfg->output_state ^ gpio_cfg->invert) << gpio;
	ret = as3720_set_bits(as3720, AS3720_GPIO_SIGNAL_OUT_REG,
	1 << gpio, val);
	}

	return ret;
	}

	static int as3720_gpio_init_regs(struct as3720_gpio *as3720_gpio,
	struct as3720_platform_data *pdata)
	{
	int ret;
	int i;
	for (i = 0; i < pdata->num_gpio_cfgs; i++) {
	ret = as3720_gpio_set_config(as3720_gpio,
	&pdata->gpio_cfgs[i]);
	if (ret < 0) {
	dev_err(as3720_gpio->as3720->dev,
	"Failed to set gpio config\n");
	return ret;
	}
	}

	return 0;
	}

	#ifdef CONFIG_DEBUG_FS
	static void as3720_gpio_dbg_show(struct seq_file s, struct gpio_chip chip)
	{
	struct as3720_gpio *as3720_gpio = to_as3720_gpio(chip);
	struct as3720 *as3720 = as3720_gpio->as3720;
	int i;

	for (i = 0; i < chip->ngpio; i++) {
	int gpio = i + chip->base;
	u32 reg;
	int ret;
	const char label, pull, *direction;

	/* 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);

	ret = as3720_reg_read(as3720,
	AS3720_GPIO0_CONTROL_REG + i, &reg);
	if (ret < 0) {
	dev_err(as3720->dev,
	"GPIO control %d read failed: %d\n",
	gpio, ret);
	seq_printf(s, "\n");
	continue;
	}

	switch (reg & AS3720_GPIO_MODE_MASK) {
	case AS3720_GPIO_MODE_INPUT:
	direction = "in";
	pull = "nopull";
	break;
	case AS3720_GPIO_MODE_OUTPUT_VDDH:
	direction = "out";
	pull = "push and pull";
	break;
	case AS3720_GPIO_MODE_IO_OPEN_DRAIN:
	direction = "io";
	pull = "nopull";
	break;
	case AS3720_GPIO_MODE_INPUT_W_PULLUP:
	direction = "in";
	pull = "pullup";
	break;
	case AS3720_GPIO_MODE_INPUT_W_PULLDOWN:
	direction = "in";
	pull = "pulldown";
	break;
	case AS3720_GPIO_MODE_IO_OPEN_DRAIN_PULLUP:
	direction = "io";
	pull = "pullup";
	break;
	case AS3720_GPIO_MODE_OUTPUT_VDDL:
	direction = "out";
	pull = "push and pull";
	break;
	default:
	direction = "INVALID DIRECTION/MODE";
	pull = "INVALID PULL";
	break;
	}

	seq_printf(s, " %s %s %s\n"
	" %s (0x%4x)\n",
	direction,
	as3720_gpio_get(chip, i) ? "high" : "low",
	pull,
	reg & AS3720_GPIO_INV_MASK ? " inverted" : "",
	reg);
	}
	}
	#else
	#define as3720_gpio_dbg_show NULL
	#endif

	static struct gpio_chip as3720_gpio_chip = {
	.label = "as3720",
	.owner = THIS_MODULE,
	.direction_input = as3720_gpio_direction_in,
	.get = as3720_gpio_get,
	.direction_output = as3720_gpio_direction_out,
	.set = as3720_gpio_set,
	.to_irq = as3720_gpio_to_irq,
	.dbg_show = as3720_gpio_dbg_show,
	.can_sleep = 1,
	};

	static int as3720_gpio_probe(struct platform_device *pdev)
	{
	struct as3720 *as3720 = dev_get_drvdata(pdev->dev.parent);
	struct as3720_platform_data *pdata = dev_get_platdata(pdev->dev.parent);
	struct as3720_gpio *as3720_gpio;
	int ret;

	as3720_gpio = devm_kzalloc(&pdev->dev,
	sizeof(*as3720_gpio), GFP_KERNEL);
	if (as3720_gpio == NULL) {
	dev_err(&pdev->dev, "Memory allocaiton failure\n");
	return -ENOMEM;
	}

	as3720_gpio->as3720 = as3720;
	as3720_gpio->gpio_chip = as3720_gpio_chip;
	as3720_gpio->gpio_chip.ngpio = AS3720_NUM_GPIO;
	as3720_gpio->gpio_chip.dev = &pdev->dev;
	if (pdata && pdata->gpio_base)
	as3720_gpio->gpio_chip.base = pdata->gpio_base;
	else
	as3720_gpio->gpio_chip.base = -1;

	platform_set_drvdata(pdev, as3720_gpio);

	ret = as3720_gpio_init_regs(as3720_gpio, pdata);
	if (ret < 0) {
	dev_err(&pdev->dev, "gpio_init_regs failed\n");
	return ret;
	}

	ret = gpiochip_add(&as3720_gpio->gpio_chip);
	if (ret < 0) {
	dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
	ret);
	return ret;
	}
	return 0;
	}

	static int as3720_gpio_remove(struct platform_device *pdev)
	{
	struct as3720_gpio *as3720_gpio = platform_get_drvdata(pdev);

	return gpiochip_remove(&as3720_gpio->gpio_chip);
	}

	static struct platform_driver as3720_gpio_driver = {
	.driver.name = "as3720-gpio",
	.driver.owner = THIS_MODULE,
	.probe = as3720_gpio_probe,
	.remove = as3720_gpio_remove,
	};

	static int __init as3720_gpio_init(void)
	{
	return platform_driver_register(&as3720_gpio_driver);
	}
	subsys_initcall(as3720_gpio_init);

	static void __exit as3720_gpio_exit(void)
	{
	platform_driver_unregister(&as3720_gpio_driver);
	}
	module_exit(as3720_gpio_exit);

	MODULE_AUTHOR("Bernhard Breinbauer <bernhard.breinbauer@ams.com>");
	MODULE_DESCRIPTION("GPIO interface for AS3720 PMICs");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:as3720-gpio");