gpio: add driver for MAX7300 I2C GPIO extender (e952805d) · Commits · e / devices / android_kernel_xiaomi_sm6125

drivers/gpio/Kconfig

+12 −1

Original line number	Diff line number	Diff line
		@@ -65,6 +65,9 @@ config GPIO_SYSFS

		# put expanders in the right section, in alphabetical order

		config GPIO_MAX730X
		tristate

		comment "Memory mapped GPIO expanders:"

		config GPIO_PL061
		@@ -87,6 +90,13 @@ config GPIO_VR41XX

		comment "I2C GPIO expanders:"

		config GPIO_MAX7300
		tristate "Maxim MAX7300 GPIO expander"
		depends on I2C
		select GPIO_MAX730X
		help
		GPIO driver for Maxim MAX7301 I2C-based GPIO expander.

		config GPIO_MAX732X
		tristate "MAX7319, MAX7320-7327 I2C Port Expanders"
		depends on I2C
		@@ -226,8 +236,9 @@ comment "SPI GPIO expanders:"
		config GPIO_MAX7301
		tristate "Maxim MAX7301 GPIO expander"
		depends on SPI_MASTER
		select GPIO_MAX730X
		help
		gpio driver for Maxim MAX7301 SPI GPIO expander.
		GPIO driver for Maxim MAX7301 SPI-based GPIO expander.

		config GPIO_MCP23S08
		tristate "Microchip MCP23S08 I/O expander"

drivers/gpio/Makefile

+2 −0

Original line number	Diff line number	Diff line
		@@ -7,6 +7,8 @@ obj-$(CONFIG_GPIOLIB) += gpiolib.o
		obj-$(CONFIG_GPIO_ADP5520) += adp5520-gpio.o
		obj-$(CONFIG_GPIO_ADP5588) += adp5588-gpio.o
		obj-$(CONFIG_GPIO_LANGWELL) += langwell_gpio.o
		obj-$(CONFIG_GPIO_MAX730X) += max730x.o
		obj-$(CONFIG_GPIO_MAX7300) += max7300.o
		obj-$(CONFIG_GPIO_MAX7301) += max7301.o
		obj-$(CONFIG_GPIO_MAX732X) += max732x.o
		obj-$(CONFIG_GPIO_MC33880) += mc33880.o

drivers/gpio/max7300.c

0 → 100644

+94 −0

Original line number	Diff line number	Diff line
		/*
		* drivers/gpio/max7300.c
		*
		* Copyright (C) 2009 Wolfram Sang, Pengutronix
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*
		* Check max730x.c for further details.
		*/

		#include <linux/module.h>
		#include <linux/init.h>
		#include <linux/platform_device.h>
		#include <linux/mutex.h>
		#include <linux/i2c.h>
		#include <linux/spi/max7301.h>

		static int max7300_i2c_write(struct device *dev, unsigned int reg,
		unsigned int val)
		{
		struct i2c_client *client = to_i2c_client(dev);

		return i2c_smbus_write_byte_data(client, reg, val);
		}

		static int max7300_i2c_read(struct device *dev, unsigned int reg)
		{
		struct i2c_client *client = to_i2c_client(dev);

		return i2c_smbus_read_byte_data(client, reg);
		}

		static int __devinit max7300_probe(struct i2c_client *client,
		const struct i2c_device_id *id)
		{
		struct max7301 *ts;
		int ret;

		if (!i2c_check_functionality(client->adapter,
		I2C_FUNC_SMBUS_BYTE_DATA))
		return -EIO;

		ts = kzalloc(sizeof(struct max7301), GFP_KERNEL);
		if (!ts)
		return -ENOMEM;

		ts->read = max7300_i2c_read;
		ts->write = max7300_i2c_write;
		ts->dev = &client->dev;

		ret = __max730x_probe(ts);
		if (ret)
		kfree(ts);
		return ret;
		}

		static int __devexit max7300_remove(struct i2c_client *client)
		{
		return __max730x_remove(&client->dev);
		}

		static const struct i2c_device_id max7300_id[] = {
		{ "max7300", 0 },
		{ }
		};
		MODULE_DEVICE_TABLE(i2c, max7300_id);

		static struct i2c_driver max7300_driver = {
		.driver = {
		.name = "max7300",
		.owner = THIS_MODULE,
		},
		.probe = max7300_probe,
		.remove = __devexit_p(max7300_remove),
		.id_table = max7300_id,
		};

		static int __init max7300_init(void)
		{
		return i2c_add_driver(&max7300_driver);
		}
		subsys_initcall(max7300_init);

		static void __exit max7300_exit(void)
		{
		i2c_del_driver(&max7300_driver);
		}
		module_exit(max7300_exit);

		MODULE_AUTHOR("Wolfram Sang");
		MODULE_LICENSE("GPL v2");
		MODULE_DESCRIPTION("MAX7300 GPIO-Expander");

drivers/gpio/max7301.c

+34 −259

Original line number	Diff line number	Diff line
		/**
		/*
		* drivers/gpio/max7301.c
		*
		* Copyright (C) 2006 Juergen Beisert, Pengutronix
		* Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
		* Copyright (C) 2009 Wolfram Sang, Pengutronix
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*
		* The Maxim's MAX7301 device is an SPI driven GPIO expander. There are
		* 28 GPIOs. 8 of them can trigger an interrupt. See datasheet for more
		* details
		* Note:
		* - DIN must be stable at the rising edge of clock.
		* - when writing:
		* - always clock in 16 clocks at once
		* - at DIN: D15 first, D0 last
		* - D0..D7 = databyte, D8..D14 = commandbyte
		* - D15 = low -> write command
		* - when reading
		* - always clock in 16 clocks at once
		* - at DIN: D15 first, D0 last
		* - D0..D7 = dummy, D8..D14 = register address
		* - D15 = high -> read command
		* - raise CS and assert it again
		* - always clock in 16 clocks at once
		* - at DOUT: D15 first, D0 last
		* - D0..D7 contains the data from the first cycle
		*
		* The driver exports a standard gpiochip interface
		* Check max730x.c for further details.
		*/

		#include <linux/module.h>
		#include <linux/init.h>
		#include <linux/platform_device.h>
		#include <linux/mutex.h>
		#include <linux/spi/spi.h>
		#include <linux/spi/max7301.h>
		#include <linux/gpio.h>

		#define DRIVER_NAME "max7301"

		/*
		* Pin configurations, see MAX7301 datasheet page 6
		*/
		#define PIN_CONFIG_MASK 0x03
		#define PIN_CONFIG_IN_PULLUP 0x03
		#define PIN_CONFIG_IN_WO_PULLUP 0x02
		#define PIN_CONFIG_OUT 0x01

		#define PIN_NUMBER 28


		/*
		* Some registers must be read back to modify.
		* To save time we cache them here in memory
		*/
		struct max7301 {
		struct mutex lock;
		u8 port_config[8]; /* field 0 is unused */
		u32 out_level; /* cached output levels */
		struct gpio_chip chip;
		struct spi_device *spi;
		};

		/**
		* max7301_write - Write a new register content
		* @spi: The SPI device
		* @reg: Register offset
		* @val: Value to write
		*
		* A write to the MAX7301 means one message with one transfer
		*
		* Returns 0 if successful or a negative value on error
		*/
		static int max7301_write(struct spi_device *spi, unsigned int reg, unsigned int val)
		/* A write to the MAX7301 means one message with one transfer */
		static int max7301_spi_write(struct device *dev, unsigned int reg,
		unsigned int val)
		{
		struct spi_device *spi = to_spi_device(dev);
		u16 word = ((reg & 0x7F) << 8) \| (val & 0xFF);

		return spi_write(spi, (const u8 *)&word, sizeof(word));
		}

		/**
		* max7301_read - Read back register content
		* @spi: The SPI device
		* @reg: Register offset
		*
		* A read from the MAX7301 means two transfers; here, one message each
		*
		* Returns positive 8 bit value from device if successful or a
		* negative value on error
		*/
		static int max7301_read(struct spi_device *spi, unsigned int reg)
		/* A read from the MAX7301 means two transfers; here, one message each */

		static int max7301_spi_read(struct device *dev, unsigned int reg)
		{
		int ret;
		u16 word;
		struct spi_device *spi = to_spi_device(dev);

		word = 0x8000 \| (reg << 8);
		ret = spi_write(spi, (const u8 *)&word, sizeof(word));
		@@ -108,125 +51,13 @@ static int max7301_read(struct spi_device *spi, unsigned int reg)
		return word & 0xff;
		}

		static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);
		u8 *config;
		int ret;

		/* First 4 pins are unused in the controller */
		offset += 4;

		config = &ts->port_config[offset >> 2];

		mutex_lock(&ts->lock);

		/* Standard GPIO API doesn't support pull-ups, has to be extended.
		* Hard-coding no pollup for now. */
		config = (config & ~(3 << (offset & 3))) \| (1 << (offset & 3));

		ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);

		mutex_unlock(&ts->lock);

		return ret;
		}

		static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
		{
		if (value) {
		ts->out_level \|= 1 << offset;
		return max7301_write(ts->spi, 0x20 + offset, 0x01);
		} else {
		ts->out_level &= ~(1 << offset);
		return max7301_write(ts->spi, 0x20 + offset, 0x00);
		}
		}

		static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
		int value)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);
		u8 *config;
		int ret;

		/* First 4 pins are unused in the controller */
		offset += 4;

		config = &ts->port_config[offset >> 2];

		mutex_lock(&ts->lock);

		config = (config & ~(3 << (offset & 3))) \| (1 << (offset & 3));

		ret = __max7301_set(ts, offset, value);

		if (!ret)
		ret = max7301_write(ts->spi, 0x08 + (offset >> 2), *config);

		mutex_unlock(&ts->lock);

		return ret;
		}

		static int max7301_get(struct gpio_chip *chip, unsigned offset)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);
		int config, level = -EINVAL;

		/* First 4 pins are unused in the controller */
		offset += 4;

		mutex_lock(&ts->lock);

		config = (ts->port_config[offset >> 2] >> ((offset & 3) * 2)) & 3;

		switch (config) {
		case 1:
		/* Output: return cached level */
		level = !!(ts->out_level & (1 << offset));
		break;
		case 2:
		case 3:
		/* Input: read out */
		level = max7301_read(ts->spi, 0x20 + offset) & 0x01;
		}
		mutex_unlock(&ts->lock);

		return level;
		}

		static void max7301_set(struct gpio_chip *chip, unsigned offset, int value)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);

		/* First 4 pins are unused in the controller */
		offset += 4;

		mutex_lock(&ts->lock);

		__max7301_set(ts, offset, value);

		mutex_unlock(&ts->lock);
		}

		static int __devinit max7301_probe(struct spi_device *spi)
		{
		struct max7301 *ts;
		struct max7301_platform_data *pdata;
		int i, ret;

		pdata = spi->dev.platform_data;
		if (!pdata \|\| !pdata->base) {
		dev_dbg(&spi->dev, "incorrect or missing platform data\n");
		return -EINVAL;
		}
		int ret;

		/*
		* bits_per_word cannot be configured in platform data
		*/
		/* bits_per_word cannot be configured in platform data */
		spi->bits_per_word = 16;

		ret = spi_setup(spi);
		if (ret < 0)
		return ret;
		@@ -235,90 +66,35 @@ static int __devinit max7301_probe(struct spi_device *spi)
		if (!ts)
		return -ENOMEM;

		mutex_init(&ts->lock);

		dev_set_drvdata(&spi->dev, ts);

		/* Power up the chip and disable IRQ output */
		max7301_write(spi, 0x04, 0x01);
		ts->read = max7301_spi_read;
		ts->write = max7301_spi_write;
		ts->dev = &spi->dev;

		ts->spi = spi;

		ts->chip.label = DRIVER_NAME,

		ts->chip.direction_input = max7301_direction_input;
		ts->chip.get = max7301_get;
		ts->chip.direction_output = max7301_direction_output;
		ts->chip.set = max7301_set;

		ts->chip.base = pdata->base;
		ts->chip.ngpio = PIN_NUMBER;
		ts->chip.can_sleep = 1;
		ts->chip.dev = &spi->dev;
		ts->chip.owner = THIS_MODULE;

		/*
		* tristate all pins in hardware and cache the
		* register values for later use.
		*/
		for (i = 1; i < 8; i++) {
		int j;
		/* 0xAA means input with internal pullup disabled */
		max7301_write(spi, 0x08 + i, 0xAA);
		ts->port_config[i] = 0xAA;
		for (j = 0; j < 4; j++) {
		int offset = (i - 1) * 4 + j;
		ret = max7301_direction_input(&ts->chip, offset);
		ret = __max730x_probe(ts);
		if (ret)
		goto exit_destroy;
		}
		}

		ret = gpiochip_add(&ts->chip);
		if (ret)
		goto exit_destroy;

		return ret;

		exit_destroy:
		dev_set_drvdata(&spi->dev, NULL);
		mutex_destroy(&ts->lock);
		kfree(ts);
		return ret;
		}

		static int __devexit max7301_remove(struct spi_device *spi)
		{
		struct max7301 *ts;
		int ret;

		ts = dev_get_drvdata(&spi->dev);
		if (ts == NULL)
		return -ENODEV;

		dev_set_drvdata(&spi->dev, NULL);

		/* Power down the chip and disable IRQ output */
		max7301_write(spi, 0x04, 0x00);

		ret = gpiochip_remove(&ts->chip);
		if (!ret) {
		mutex_destroy(&ts->lock);
		kfree(ts);
		} else
		dev_err(&spi->dev, "Failed to remove the GPIO controller: %d\n",
		ret);

		return ret;
		return __max730x_remove(&spi->dev);
		}

		static const struct spi_device_id max7301_id[] = {
		{ "max7301", 0 },
		{ }
		};
		MODULE_DEVICE_TABLE(spi, max7301_id);

		static struct spi_driver max7301_driver = {
		.driver = {
		.name = DRIVER_NAME,
		.name = "max7301",
		.owner = THIS_MODULE,
		},
		.probe = max7301_probe,
		.remove = __devexit_p(max7301_remove),
		.id_table = max7301_id,
		};

		static int __init max7301_init(void)
		@@ -336,7 +112,6 @@ static void __exit max7301_exit(void)
		}
		module_exit(max7301_exit);

		MODULE_AUTHOR("Juergen Beisert");
		MODULE_AUTHOR("Juergen Beisert, Wolfram Sang");
		MODULE_LICENSE("GPL v2");
		MODULE_DESCRIPTION("MAX7301 SPI based GPIO-Expander");
		MODULE_ALIAS("spi:" DRIVER_NAME);
		MODULE_DESCRIPTION("MAX7301 GPIO-Expander");

drivers/gpio/max730x.c

0 → 100644

+244 −0

Original line number	Diff line number	Diff line
		/**
		* drivers/gpio/max7301.c
		*
		* Copyright (C) 2006 Juergen Beisert, Pengutronix
		* Copyright (C) 2008 Guennadi Liakhovetski, Pengutronix
		* Copyright (C) 2009 Wolfram Sang, Pengutronix
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 as
		* published by the Free Software Foundation.
		*
		* The Maxim MAX7300/1 device is an I2C/SPI driven GPIO expander. There are
		* 28 GPIOs. 8 of them can trigger an interrupt. See datasheet for more
		* details
		* Note:
		* - DIN must be stable at the rising edge of clock.
		* - when writing:
		* - always clock in 16 clocks at once
		* - at DIN: D15 first, D0 last
		* - D0..D7 = databyte, D8..D14 = commandbyte
		* - D15 = low -> write command
		* - when reading
		* - always clock in 16 clocks at once
		* - at DIN: D15 first, D0 last
		* - D0..D7 = dummy, D8..D14 = register address
		* - D15 = high -> read command
		* - raise CS and assert it again
		* - always clock in 16 clocks at once
		* - at DOUT: D15 first, D0 last
		* - D0..D7 contains the data from the first cycle
		*
		* The driver exports a standard gpiochip interface
		*/

		#include <linux/module.h>
		#include <linux/init.h>
		#include <linux/platform_device.h>
		#include <linux/mutex.h>
		#include <linux/spi/max7301.h>
		#include <linux/gpio.h>

		/*
		* Pin configurations, see MAX7301 datasheet page 6
		*/
		#define PIN_CONFIG_MASK 0x03
		#define PIN_CONFIG_IN_PULLUP 0x03
		#define PIN_CONFIG_IN_WO_PULLUP 0x02
		#define PIN_CONFIG_OUT 0x01

		#define PIN_NUMBER 28

		static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);
		u8 *config;
		u8 offset_bits;
		int ret;

		/* First 4 pins are unused in the controller */
		offset += 4;
		offset_bits = (offset & 3) << 1;

		config = &ts->port_config[offset >> 2];

		mutex_lock(&ts->lock);

		/* Standard GPIO API doesn't support pull-ups, has to be extended.
		* Hard-coding no pollup for now. */
		config = (config & ~(PIN_CONFIG_MASK << offset_bits))
		\| (PIN_CONFIG_IN_WO_PULLUP << offset_bits);

		ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);

		mutex_unlock(&ts->lock);

		return ret;
		}

		static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
		{
		if (value) {
		ts->out_level \|= 1 << offset;
		return ts->write(ts->dev, 0x20 + offset, 0x01);
		} else {
		ts->out_level &= ~(1 << offset);
		return ts->write(ts->dev, 0x20 + offset, 0x00);
		}
		}

		static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
		int value)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);
		u8 *config;
		u8 offset_bits;
		int ret;

		/* First 4 pins are unused in the controller */
		offset += 4;
		offset_bits = (offset & 3) << 1;

		config = &ts->port_config[offset >> 2];

		mutex_lock(&ts->lock);

		config = (config & ~(PIN_CONFIG_MASK << offset_bits))
		\| (PIN_CONFIG_OUT << offset_bits);

		ret = __max7301_set(ts, offset, value);

		if (!ret)
		ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);

		mutex_unlock(&ts->lock);

		return ret;
		}

		static int max7301_get(struct gpio_chip *chip, unsigned offset)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);
		int config, level = -EINVAL;

		/* First 4 pins are unused in the controller */
		offset += 4;

		mutex_lock(&ts->lock);

		config = (ts->port_config[offset >> 2] >> ((offset & 3) << 1))
		& PIN_CONFIG_MASK;

		switch (config) {
		case PIN_CONFIG_OUT:
		/* Output: return cached level */
		level = !!(ts->out_level & (1 << offset));
		break;
		case PIN_CONFIG_IN_WO_PULLUP:
		case PIN_CONFIG_IN_PULLUP:
		/* Input: read out */
		level = ts->read(ts->dev, 0x20 + offset) & 0x01;
		}
		mutex_unlock(&ts->lock);

		return level;
		}

		static void max7301_set(struct gpio_chip *chip, unsigned offset, int value)
		{
		struct max7301 *ts = container_of(chip, struct max7301, chip);

		/* First 4 pins are unused in the controller */
		offset += 4;

		mutex_lock(&ts->lock);

		__max7301_set(ts, offset, value);

		mutex_unlock(&ts->lock);
		}

		int __devinit __max730x_probe(struct max7301 *ts)
		{
		struct device *dev = ts->dev;
		struct max7301_platform_data *pdata;
		int i, ret;

		pdata = dev->platform_data;
		if (!pdata \|\| !pdata->base) {
		dev_err(dev, "incorrect or missing platform data\n");
		return -EINVAL;
		}

		mutex_init(&ts->lock);
		dev_set_drvdata(dev, ts);

		/* Power up the chip and disable IRQ output */
		ts->write(dev, 0x04, 0x01);

		ts->chip.label = dev->driver->name;

		ts->chip.direction_input = max7301_direction_input;
		ts->chip.get = max7301_get;
		ts->chip.direction_output = max7301_direction_output;
		ts->chip.set = max7301_set;

		ts->chip.base = pdata->base;
		ts->chip.ngpio = PIN_NUMBER;
		ts->chip.can_sleep = 1;
		ts->chip.dev = dev;
		ts->chip.owner = THIS_MODULE;

		/*
		* tristate all pins in hardware and cache the
		* register values for later use.
		*/
		for (i = 1; i < 8; i++) {
		int j;
		/* 0xAA means input with internal pullup disabled */
		ts->write(dev, 0x08 + i, 0xAA);
		ts->port_config[i] = 0xAA;
		for (j = 0; j < 4; j++) {
		int offset = (i - 1) * 4 + j;
		ret = max7301_direction_input(&ts->chip, offset);
		if (ret)
		goto exit_destroy;
		}
		}

		ret = gpiochip_add(&ts->chip);
		if (ret)
		goto exit_destroy;

		return ret;

		exit_destroy:
		dev_set_drvdata(dev, NULL);
		mutex_destroy(&ts->lock);
		return ret;
		}
		EXPORT_SYMBOL_GPL(__max730x_probe);

		int __devexit __max730x_remove(struct device *dev)
		{
		struct max7301 *ts = dev_get_drvdata(dev);
		int ret;

		if (ts == NULL)
		return -ENODEV;

		dev_set_drvdata(dev, NULL);

		/* Power down the chip and disable IRQ output */
		ts->write(dev, 0x04, 0x00);

		ret = gpiochip_remove(&ts->chip);
		if (!ret) {
		mutex_destroy(&ts->lock);
		kfree(ts);
		} else
		dev_err(dev, "Failed to remove GPIO controller: %d\n", ret);

		return ret;
		}
		EXPORT_SYMBOL_GPL(__max730x_remove);