drivers/mfd/tc35892.c - kernel/skids - Git at Google

 /*
  * Copyright (C) ST-Ericsson SA 2010
  *
  * License Terms: GNU General Public License, version 2
  * Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
  * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
  */

 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/tc35892.h>

 /**
  * tc35892_reg_read() - read a single TC35892 register
  * @tc35892:	Device to read from
  * @reg:	Register to read
  */
 int tc35892_reg_read(struct tc35892 *tc35892, u8 reg)
 {
 	int ret;

 	ret = i2c_smbus_read_byte_data(tc35892->i2c, reg);
 	if (ret < 0)
 		dev_err(tc35892->dev, "failed to read reg %#x: %d\n",
 			reg, ret);

 	return ret;
 }
 EXPORT_SYMBOL_GPL(tc35892_reg_read);

 /**
  * tc35892_reg_read() - write a single TC35892 register
  * @tc35892:	Device to write to
  * @reg:	Register to read
  * @data:	Value to write
  */
 int tc35892_reg_write(struct tc35892 *tc35892, u8 reg, u8 data)
 {
 	int ret;

 	ret = i2c_smbus_write_byte_data(tc35892->i2c, reg, data);
 	if (ret < 0)
 		dev_err(tc35892->dev, "failed to write reg %#x: %d\n",
 			reg, ret);

 	return ret;
 }
 EXPORT_SYMBOL_GPL(tc35892_reg_write);

 /**
  * tc35892_block_read() - read multiple TC35892 registers
  * @tc35892:	Device to read from
  * @reg:	First register
  * @length:	Number of registers
  * @values:	Buffer to write to
  */
 int tc35892_block_read(struct tc35892 *tc35892, u8 reg, u8 length, u8 *values)
 {
 	int ret;

 	ret = i2c_smbus_read_i2c_block_data(tc35892->i2c, reg, length, values);
 	if (ret < 0)
 		dev_err(tc35892->dev, "failed to read regs %#x: %d\n",
 			reg, ret);

 	return ret;
 }
 EXPORT_SYMBOL_GPL(tc35892_block_read);

 /**
  * tc35892_block_write() - write multiple TC35892 registers
  * @tc35892:	Device to write to
  * @reg:	First register
  * @length:	Number of registers
  * @values:	Values to write
  */
 int tc35892_block_write(struct tc35892 *tc35892, u8 reg, u8 length,
 			const u8 *values)
 {
 	int ret;

 	ret = i2c_smbus_write_i2c_block_data(tc35892->i2c, reg, length,
 					     values);
 	if (ret < 0)
 		dev_err(tc35892->dev, "failed to write regs %#x: %d\n",
 			reg, ret);

 	return ret;
 }
 EXPORT_SYMBOL_GPL(tc35892_block_write);

 /**
  * tc35892_set_bits() - set the value of a bitfield in a TC35892 register
  * @tc35892:	Device to write to
  * @reg:	Register to write
  * @mask:	Mask of bits to set
  * @values:	Value to set
  */
 int tc35892_set_bits(struct tc35892 *tc35892, u8 reg, u8 mask, u8 val)
 {
 	int ret;

 	mutex_lock(&tc35892->lock);

 	ret = tc35892_reg_read(tc35892, reg);
 	if (ret < 0)
 		goto out;

 	ret &= ~mask;
 	ret |= val;

 	ret = tc35892_reg_write(tc35892, reg, ret);

 out:
 	mutex_unlock(&tc35892->lock);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(tc35892_set_bits);

 static struct resource gpio_resources[] = {
 	{
 		.start	= TC35892_INT_GPIIRQ,
 		.end	= TC35892_INT_GPIIRQ,
 		.flags	= IORESOURCE_IRQ,
 	},
 };

 static struct mfd_cell tc35892_devs[] = {
 	{
 		.name		= "tc35892-gpio",
 		.num_resources	= ARRAY_SIZE(gpio_resources),
 		.resources	= &gpio_resources[0],
 	},
 };

 static irqreturn_t tc35892_irq(int irq, void *data)
 {
 	struct tc35892 *tc35892 = data;
 	int status;

 	status = tc35892_reg_read(tc35892, TC35892_IRQST);
 	if (status < 0)
 		return IRQ_NONE;

 	while (status) {
 		int bit = __ffs(status);

 		handle_nested_irq(tc35892->irq_base + bit);
 		status &= ~(1 << bit);
 	}

 	/*
 	 * A dummy read or write (to any register) appears to be necessary to
 	 * have the last interrupt clear (for example, GPIO IC write) take
 	 * effect.
 	 */
 	tc35892_reg_read(tc35892, TC35892_IRQST);

 	return IRQ_HANDLED;
 }

 static void tc35892_irq_dummy(unsigned int irq)
 {
 	/* No mask/unmask at this level */
 }

 static struct irq_chip tc35892_irq_chip = {
 	.name	= "tc35892",
 	.mask	= tc35892_irq_dummy,
 	.unmask	= tc35892_irq_dummy,
 };

 static int tc35892_irq_init(struct tc35892 *tc35892)
 {
 	int base = tc35892->irq_base;
 	int irq;

 	for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
 		set_irq_chip_data(irq, tc35892);
 		set_irq_chip_and_handler(irq, &tc35892_irq_chip,
 					 handle_edge_irq);
 		set_irq_nested_thread(irq, 1);
 #ifdef CONFIG_ARM
 		set_irq_flags(irq, IRQF_VALID);
 #else
 		set_irq_noprobe(irq);
 #endif
 	}

 	return 0;
 }

 static void tc35892_irq_remove(struct tc35892 *tc35892)
 {
 	int base = tc35892->irq_base;
 	int irq;

 	for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
 #ifdef CONFIG_ARM
 		set_irq_flags(irq, 0);
 #endif
 		set_irq_chip_and_handler(irq, NULL, NULL);
 		set_irq_chip_data(irq, NULL);
 	}
 }

 static int tc35892_chip_init(struct tc35892 *tc35892)
 {
 	int manf, ver, ret;

 	manf = tc35892_reg_read(tc35892, TC35892_MANFCODE);
 	if (manf < 0)
 		return manf;

 	ver = tc35892_reg_read(tc35892, TC35892_VERSION);
 	if (ver < 0)
 		return ver;

 	if (manf != TC35892_MANFCODE_MAGIC) {
 		dev_err(tc35892->dev, "unknown manufacturer: %#x\n", manf);
 		return -EINVAL;
 	}

 	dev_info(tc35892->dev, "manufacturer: %#x, version: %#x\n", manf, ver);

 	/* Put everything except the IRQ module into reset */
 	ret = tc35892_reg_write(tc35892, TC35892_RSTCTRL,
 				TC35892_RSTCTRL_TIMRST
 				| TC35892_RSTCTRL_ROTRST
 				| TC35892_RSTCTRL_KBDRST
 				| TC35892_RSTCTRL_GPIRST);
 	if (ret < 0)
 		return ret;

 	/* Clear the reset interrupt. */
 	return tc35892_reg_write(tc35892, TC35892_RSTINTCLR, 0x1);
 }

 static int __devinit tc35892_probe(struct i2c_client *i2c,
 				   const struct i2c_device_id *id)
 {
 	struct tc35892_platform_data *pdata = i2c->dev.platform_data;
 	struct tc35892 *tc35892;
 	int ret;

 	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
 				     | I2C_FUNC_SMBUS_I2C_BLOCK))
 		return -EIO;

 	tc35892 = kzalloc(sizeof(struct tc35892), GFP_KERNEL);
 	if (!tc35892)
 		return -ENOMEM;

 	mutex_init(&tc35892->lock);

 	tc35892->dev = &i2c->dev;
 	tc35892->i2c = i2c;
 	tc35892->pdata = pdata;
 	tc35892->irq_base = pdata->irq_base;
 	tc35892->num_gpio = id->driver_data;

 	i2c_set_clientdata(i2c, tc35892);

 	ret = tc35892_chip_init(tc35892);
 	if (ret)
 		goto out_free;

 	ret = tc35892_irq_init(tc35892);
 	if (ret)
 		goto out_free;

 	ret = request_threaded_irq(tc35892->i2c->irq, NULL, tc35892_irq,
 				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 				   "tc35892", tc35892);
 	if (ret) {
 		dev_err(tc35892->dev, "failed to request IRQ: %d\n", ret);
 		goto out_removeirq;
 	}

 	ret = mfd_add_devices(tc35892->dev, -1, tc35892_devs,
 			      ARRAY_SIZE(tc35892_devs), NULL,
 			      tc35892->irq_base);
 	if (ret) {
 		dev_err(tc35892->dev, "failed to add children\n");
 		goto out_freeirq;
 	}

 	return 0;

 out_freeirq:
 	free_irq(tc35892->i2c->irq, tc35892);
 out_removeirq:
 	tc35892_irq_remove(tc35892);
 out_free:
 	kfree(tc35892);
 	return ret;
 }

 static int __devexit tc35892_remove(struct i2c_client *client)
 {
 	struct tc35892 *tc35892 = i2c_get_clientdata(client);

 	mfd_remove_devices(tc35892->dev);

 	free_irq(tc35892->i2c->irq, tc35892);
 	tc35892_irq_remove(tc35892);

 	kfree(tc35892);

 	return 0;
 }

 static const struct i2c_device_id tc35892_id[] = {
 	{ "tc35892", 24 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, tc35892_id);

 static struct i2c_driver tc35892_driver = {
 	.driver.name	= "tc35892",
 	.driver.owner	= THIS_MODULE,
 	.probe		= tc35892_probe,
 	.remove		= __devexit_p(tc35892_remove),
 	.id_table	= tc35892_id,
 };

 static int __init tc35892_init(void)
 {
 	return i2c_add_driver(&tc35892_driver);
 }
 subsys_initcall(tc35892_init);

 static void __exit tc35892_exit(void)
 {
 	i2c_del_driver(&tc35892_driver);
 }
 module_exit(tc35892_exit);

 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("TC35892 MFD core driver");
 MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");
	/*
	* Copyright (C) ST-Ericsson SA 2010
	*
	* License Terms: GNU General Public License, version 2
	* Author: Hanumath Prasad <hanumath.prasad@stericsson.com> for ST-Ericsson
	* Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
	*/

	#include <linux/module.h>
	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/slab.h>
	#include <linux/i2c.h>
	#include <linux/mfd/core.h>
	#include <linux/mfd/tc35892.h>

	/**
	* tc35892_reg_read() - read a single TC35892 register
	* @tc35892: Device to read from
	* @reg: Register to read
	*/
	int tc35892_reg_read(struct tc35892 *tc35892, u8 reg)
	{
	int ret;

	ret = i2c_smbus_read_byte_data(tc35892->i2c, reg);
	if (ret < 0)
	dev_err(tc35892->dev, "failed to read reg %#x: %d\n",
	reg, ret);

	return ret;
	}
	EXPORT_SYMBOL_GPL(tc35892_reg_read);

	/**
	* tc35892_reg_read() - write a single TC35892 register
	* @tc35892: Device to write to
	* @reg: Register to read
	* @data: Value to write
	*/
	int tc35892_reg_write(struct tc35892 *tc35892, u8 reg, u8 data)
	{
	int ret;

	ret = i2c_smbus_write_byte_data(tc35892->i2c, reg, data);
	if (ret < 0)
	dev_err(tc35892->dev, "failed to write reg %#x: %d\n",
	reg, ret);

	return ret;
	}
	EXPORT_SYMBOL_GPL(tc35892_reg_write);

	/**
	* tc35892_block_read() - read multiple TC35892 registers
	* @tc35892: Device to read from
	* @reg: First register
	* @length: Number of registers
	* @values: Buffer to write to
	*/
	int tc35892_block_read(struct tc35892 tc35892, u8 reg, u8 length, u8 values)
	{
	int ret;

	ret = i2c_smbus_read_i2c_block_data(tc35892->i2c, reg, length, values);
	if (ret < 0)
	dev_err(tc35892->dev, "failed to read regs %#x: %d\n",
	reg, ret);

	return ret;
	}
	EXPORT_SYMBOL_GPL(tc35892_block_read);

	/**
	* tc35892_block_write() - write multiple TC35892 registers
	* @tc35892: Device to write to
	* @reg: First register
	* @length: Number of registers
	* @values: Values to write
	*/
	int tc35892_block_write(struct tc35892 *tc35892, u8 reg, u8 length,
	const u8 *values)
	{
	int ret;

	ret = i2c_smbus_write_i2c_block_data(tc35892->i2c, reg, length,
	values);
	if (ret < 0)
	dev_err(tc35892->dev, "failed to write regs %#x: %d\n",
	reg, ret);

	return ret;
	}
	EXPORT_SYMBOL_GPL(tc35892_block_write);

	/**
	* tc35892_set_bits() - set the value of a bitfield in a TC35892 register
	* @tc35892: Device to write to
	* @reg: Register to write
	* @mask: Mask of bits to set
	* @values: Value to set
	*/
	int tc35892_set_bits(struct tc35892 *tc35892, u8 reg, u8 mask, u8 val)
	{
	int ret;

	mutex_lock(&tc35892->lock);

	ret = tc35892_reg_read(tc35892, reg);
	if (ret < 0)
	goto out;

	ret &= ~mask;
	ret \|= val;

	ret = tc35892_reg_write(tc35892, reg, ret);

	out:
	mutex_unlock(&tc35892->lock);
	return ret;
	}
	EXPORT_SYMBOL_GPL(tc35892_set_bits);

	static struct resource gpio_resources[] = {
	{
	.start = TC35892_INT_GPIIRQ,
	.end = TC35892_INT_GPIIRQ,
	.flags = IORESOURCE_IRQ,
	},
	};

	static struct mfd_cell tc35892_devs[] = {
	{
	.name = "tc35892-gpio",
	.num_resources = ARRAY_SIZE(gpio_resources),
	.resources = &gpio_resources[0],
	},
	};

	static irqreturn_t tc35892_irq(int irq, void *data)
	{
	struct tc35892 *tc35892 = data;
	int status;

	status = tc35892_reg_read(tc35892, TC35892_IRQST);
	if (status < 0)
	return IRQ_NONE;

	while (status) {
	int bit = __ffs(status);

	handle_nested_irq(tc35892->irq_base + bit);
	status &= ~(1 << bit);
	}

	/*
	* A dummy read or write (to any register) appears to be necessary to
	* have the last interrupt clear (for example, GPIO IC write) take
	* effect.
	*/
	tc35892_reg_read(tc35892, TC35892_IRQST);

	return IRQ_HANDLED;
	}

	static void tc35892_irq_dummy(unsigned int irq)
	{
	/* No mask/unmask at this level */
	}

	static struct irq_chip tc35892_irq_chip = {
	.name = "tc35892",
	.mask = tc35892_irq_dummy,
	.unmask = tc35892_irq_dummy,
	};

	static int tc35892_irq_init(struct tc35892 *tc35892)
	{
	int base = tc35892->irq_base;
	int irq;

	for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
	set_irq_chip_data(irq, tc35892);
	set_irq_chip_and_handler(irq, &tc35892_irq_chip,
	handle_edge_irq);
	set_irq_nested_thread(irq, 1);
	#ifdef CONFIG_ARM
	set_irq_flags(irq, IRQF_VALID);
	#else
	set_irq_noprobe(irq);
	#endif
	}

	return 0;
	}

	static void tc35892_irq_remove(struct tc35892 *tc35892)
	{
	int base = tc35892->irq_base;
	int irq;

	for (irq = base; irq < base + TC35892_NR_INTERNAL_IRQS; irq++) {
	#ifdef CONFIG_ARM
	set_irq_flags(irq, 0);
	#endif
	set_irq_chip_and_handler(irq, NULL, NULL);
	set_irq_chip_data(irq, NULL);
	}
	}

	static int tc35892_chip_init(struct tc35892 *tc35892)
	{
	int manf, ver, ret;

	manf = tc35892_reg_read(tc35892, TC35892_MANFCODE);
	if (manf < 0)
	return manf;

	ver = tc35892_reg_read(tc35892, TC35892_VERSION);
	if (ver < 0)
	return ver;

	if (manf != TC35892_MANFCODE_MAGIC) {
	dev_err(tc35892->dev, "unknown manufacturer: %#x\n", manf);
	return -EINVAL;
	}

	dev_info(tc35892->dev, "manufacturer: %#x, version: %#x\n", manf, ver);

	/* Put everything except the IRQ module into reset */
	ret = tc35892_reg_write(tc35892, TC35892_RSTCTRL,
	TC35892_RSTCTRL_TIMRST
	\| TC35892_RSTCTRL_ROTRST
	\| TC35892_RSTCTRL_KBDRST
	\| TC35892_RSTCTRL_GPIRST);
	if (ret < 0)
	return ret;

	/* Clear the reset interrupt. */
	return tc35892_reg_write(tc35892, TC35892_RSTINTCLR, 0x1);
	}

	static int __devinit tc35892_probe(struct i2c_client *i2c,
	const struct i2c_device_id *id)
	{
	struct tc35892_platform_data *pdata = i2c->dev.platform_data;
	struct tc35892 *tc35892;
	int ret;

	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
	\| I2C_FUNC_SMBUS_I2C_BLOCK))
	return -EIO;

	tc35892 = kzalloc(sizeof(struct tc35892), GFP_KERNEL);
	if (!tc35892)
	return -ENOMEM;

	mutex_init(&tc35892->lock);

	tc35892->dev = &i2c->dev;
	tc35892->i2c = i2c;
	tc35892->pdata = pdata;
	tc35892->irq_base = pdata->irq_base;
	tc35892->num_gpio = id->driver_data;

	i2c_set_clientdata(i2c, tc35892);

	ret = tc35892_chip_init(tc35892);
	if (ret)
	goto out_free;

	ret = tc35892_irq_init(tc35892);
	if (ret)
	goto out_free;

	ret = request_threaded_irq(tc35892->i2c->irq, NULL, tc35892_irq,
	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
	"tc35892", tc35892);
	if (ret) {
	dev_err(tc35892->dev, "failed to request IRQ: %d\n", ret);
	goto out_removeirq;
	}

	ret = mfd_add_devices(tc35892->dev, -1, tc35892_devs,
	ARRAY_SIZE(tc35892_devs), NULL,
	tc35892->irq_base);
	if (ret) {
	dev_err(tc35892->dev, "failed to add children\n");
	goto out_freeirq;
	}

	return 0;

	out_freeirq:
	free_irq(tc35892->i2c->irq, tc35892);
	out_removeirq:
	tc35892_irq_remove(tc35892);
	out_free:
	kfree(tc35892);
	return ret;
	}

	static int __devexit tc35892_remove(struct i2c_client *client)
	{
	struct tc35892 *tc35892 = i2c_get_clientdata(client);

	mfd_remove_devices(tc35892->dev);

	free_irq(tc35892->i2c->irq, tc35892);
	tc35892_irq_remove(tc35892);

	kfree(tc35892);

	return 0;
	}

	static const struct i2c_device_id tc35892_id[] = {
	{ "tc35892", 24 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, tc35892_id);

	static struct i2c_driver tc35892_driver = {
	.driver.name = "tc35892",
	.driver.owner = THIS_MODULE,
	.probe = tc35892_probe,
	.remove = __devexit_p(tc35892_remove),
	.id_table = tc35892_id,
	};

	static int __init tc35892_init(void)
	{
	return i2c_add_driver(&tc35892_driver);
	}
	subsys_initcall(tc35892_init);

	static void __exit tc35892_exit(void)
	{
	i2c_del_driver(&tc35892_driver);
	}
	module_exit(tc35892_exit);

	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("TC35892 MFD core driver");
	MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");