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    Subject[PATCH 2/3 V2] gpio: add STMPE811 gpio controller support
    Date
    This one adds a driver for STMPE811 GPIO controller. STMPE811 is a
    multifunction device. Hence this driver depends on stmpe811_core
    driver for core functionalities. The gpio chip is registered to
    gpiolib. Interrupts are currently not supported.

    Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
    ---
    V2 changes:
    * include subsystem headers since they are now removed from the mfd
    core header file

    drivers/gpio/Kconfig | 10 ++
    drivers/gpio/Makefile | 1 +
    drivers/gpio/stmpe811_gpio.c | 238 ++++++++++++++++++++++++++++++++++++++++++
    3 files changed, 249 insertions(+), 0 deletions(-)
    create mode 100644 drivers/gpio/stmpe811_gpio.c

    diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
    index 724038d..38307e5 100644
    --- a/drivers/gpio/Kconfig
    +++ b/drivers/gpio/Kconfig
    @@ -249,6 +249,16 @@ config GPIO_ADP5588
    To compile this driver as a module, choose M here: the module will be
    called adp5588-gpio.

    +config GPIO_STMPE811
    + tristate "STMPE811 I2C MFD GPIO expander"
    + depends on I2C
    + depends on MFD_STMPE811
    + help
    + This option enables support for 8 GPIOs found
    + on STMicroelectronics STMPE811 multifunction devices.
    + To compile this driver as a module, choose M here: the module will be
    + called stmpe811_gpio.
    +
    comment "PCI GPIO expanders:"

    config GPIO_CS5535
    diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
    index 51c3cdd..7b184aa 100644
    --- a/drivers/gpio/Makefile
    +++ b/drivers/gpio/Makefile
    @@ -31,3 +31,4 @@ obj-$(CONFIG_GPIO_WM8994) += wm8994-gpio.o
    obj-$(CONFIG_GPIO_SCH) += sch_gpio.o
    obj-$(CONFIG_GPIO_RDC321X) += rdc321x-gpio.o
    obj-$(CONFIG_GPIO_JANZ_TTL) += janz-ttl.o
    +obj-$(CONFIG_GPIO_STMPE811) += stmpe811_gpio.o
    diff --git a/drivers/gpio/stmpe811_gpio.c b/drivers/gpio/stmpe811_gpio.c
    new file mode 100644
    index 0000000..507fb5b
    --- /dev/null
    +++ b/drivers/gpio/stmpe811_gpio.c
    @@ -0,0 +1,238 @@
    +/*
    + * stmpe811_gpio.c -- gpiolib support for STMicroelectronics STMPE811 chip.
    + *
    + * (c)2010 Luotao Fu <l.fu@pengutronix.de>
    + *
    + * 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/module.h>
    +#include <linux/interrupt.h>
    +#include <linux/slab.h>
    +#include <linux/gpio.h>
    +#include <linux/platform_device.h>
    +#include <linux/i2c.h>
    +#include <linux/workqueue.h>
    +
    +#include <linux/mfd/stmpe811.h>
    +
    +#define STMPE811_GPIO_NAME "stmpe811-gpio"
    +
    +struct stmpe811_gpio {
    + struct stmpe811 *stm;
    + struct gpio_chip gpio;
    +};
    +
    +static inline struct stmpe811_gpio *to_stmpe811_gpio(struct gpio_chip *chip)
    +{
    + return container_of(chip, struct stmpe811_gpio, gpio);
    +}
    +
    +static int stmpe811_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
    +{
    + struct stmpe811_gpio *stm_gpio = to_stmpe811_gpio(chip);
    +
    + return stmpe811_reg_clear_bits(stm_gpio->stm,
    + STMPE811_REG_GPIO_DIR, BIT(offset));
    +}
    +
    +static int stmpe811_gpio_get(struct gpio_chip *chip, unsigned offset)
    +{
    + struct stmpe811_gpio *stm_gpio = to_stmpe811_gpio(chip);
    + uint8_t gpio_sta;
    + int ret;
    +
    + ret = stmpe811_reg_read(stm_gpio->stm,
    + STMPE811_REG_GPIO_MP_STA, &gpio_sta);
    + if (ret)
    + return ret;
    +
    + if (gpio_sta & BIT(offset))
    + return 1;
    + else
    + return 0;
    +}
    +
    +static inline int __stmpe811_gpio_set(struct stmpe811 *stm,
    + unsigned offset, int value)
    +{
    + int ret;
    +
    + if (value)
    + ret = stmpe811_reg_write(stm, STMPE811_REG_GPIO_SET_PIN,
    + BIT(offset));
    + else
    + ret = stmpe811_reg_write(stm, STMPE811_REG_GPIO_CLR_PIN,
    + BIT(offset));
    +
    + return ret;
    +}
    +
    +static int stmpe811_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
    + int value)
    +{
    + struct stmpe811_gpio *stm_gpio = to_stmpe811_gpio(chip);
    + struct stmpe811 *stm = stm_gpio->stm;
    + int ret;
    +
    + ret = stmpe811_reg_set_bits(stm, STMPE811_REG_GPIO_DIR, BIT(offset));
    + if (ret)
    + goto out;
    +
    + ret = __stmpe811_gpio_set(stm, offset, value);
    +out:
    + return ret;
    +}
    +
    +static void stmpe811_gpio_set(struct gpio_chip *chip, unsigned offset,
    + int value)
    +{
    + struct stmpe811_gpio *stm_gpio = to_stmpe811_gpio(chip);
    +
    + __stmpe811_gpio_set(stm_gpio->stm, offset, value);
    +}
    +
    +static int stmpe811_gpio_request(struct gpio_chip *chip, unsigned offset)
    +{
    + struct stmpe811_gpio *stm_gpio = to_stmpe811_gpio(chip);
    + struct stmpe811 *stm = stm_gpio->stm;
    +
    + if (offset > 3 && (stm->active_flag & STMPE811_USE_TS))
    + return 1;
    + else
    + return stmpe811_reg_set_bits(stm, STMPE811_REG_GPIO_AF,
    + BIT(offset));
    +}
    +
    +static struct gpio_chip gpio_chip = {
    + .label = STMPE811_GPIO_NAME,
    + .owner = THIS_MODULE,
    + .direction_input = stmpe811_gpio_direction_in,
    + .get = stmpe811_gpio_get,
    + .direction_output = stmpe811_gpio_direction_out,
    + .set = stmpe811_gpio_set,
    + .request = stmpe811_gpio_request,
    + .can_sleep = 1,
    +};
    +
    +static int __devinit stmpe811_gpio_probe(struct platform_device *pdev)
    +{
    + struct stmpe811 *stm = dev_get_drvdata(pdev->dev.parent);
    + struct stmpe811_platform_data *pdata = stm->pdata;
    + struct stmpe811_gpio_platform_data *gpio_pdata = NULL;
    + struct stmpe811_gpio *stm_gpio;
    +
    + int ret, tmp;
    +
    + stm_gpio = kzalloc(sizeof(*stm_gpio), GFP_KERNEL);
    + if (!stm_gpio)
    + return -ENOMEM;
    +
    + stm_gpio->stm = stm;
    + stm_gpio->gpio = gpio_chip;
    + stm_gpio->gpio.ngpio = 8;
    + stm_gpio->gpio.dev = &pdev->dev;
    +
    + if (pdata)
    + gpio_pdata = pdata->gpio_pdata;
    +
    + if (gpio_pdata && gpio_pdata->gpio_base)
    + stm_gpio->gpio.base = gpio_pdata->gpio_base;
    + else
    + stm_gpio->gpio.base = -1;
    +
    + ret = gpiochip_add(&stm_gpio->gpio);
    + if (ret < 0) {
    + dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
    + goto err_free_stmgpio;
    + }
    + /* enable clock supply */
    + ret = stmpe811_reg_clear_bits(stm, STMPE811_REG_SYS_CTRL2,
    + STMPE811_SYS_CTRL2_GPIO_OFF);
    + if (ret) {
    + dev_err(&pdev->dev, "Could not enable clock for gpio\n");
    + goto err_free_gpiochip;
    + }
    +
    + if (gpio_pdata && gpio_pdata->setup) {
    + ret = gpio_pdata->setup(stm);
    +
    + if (ret != 0) {
    + dev_err(&pdev->dev, "setup hook failed, %d\n",
    + ret);
    + goto err_free_gpiochip;
    + }
    + }
    +
    + dev_info(&pdev->dev, "registerd gpios %d..%d on a stmpe811\n",
    + stm_gpio->gpio.base,
    + stm_gpio->gpio.base + stm_gpio->gpio.ngpio - 1);
    + platform_set_drvdata(pdev, stm_gpio);
    +
    + return ret;
    +
    +err_free_gpiochip:
    + tmp = gpiochip_remove(&stm_gpio->gpio);
    + if (tmp) {
    + dev_err(&pdev->dev, "Could net remove gpio chip\n");
    + return ret;
    + }
    +err_free_stmgpio:
    + kfree(stm_gpio);
    + return ret;
    +}
    +
    +static int __devexit stmpe811_gpio_remove(struct platform_device *pdev)
    +{
    + struct stmpe811_gpio *stm_gpio = platform_get_drvdata(pdev);
    + struct stmpe811_platform_data *pdata = stm_gpio->stm->pdata;
    + struct stmpe811_gpio_platform_data *gpio_pdata = NULL;
    + int ret;
    +
    + if (pdata)
    + gpio_pdata = pdata->gpio_pdata;
    +
    + if (gpio_pdata && gpio_pdata->remove)
    + gpio_pdata->remove(stm_gpio->stm);
    +
    + /* disable clock supply */
    + stmpe811_reg_set_bits(stm_gpio->stm, STMPE811_REG_SYS_CTRL2,
    + STMPE811_SYS_CTRL2_GPIO_OFF);
    +
    + ret = gpiochip_remove(&stm_gpio->gpio);
    + if (ret == 0)
    + kfree(stm_gpio);
    +
    + return ret;
    +}
    +
    +static struct platform_driver stmpe811_gpio_driver = {
    + .driver.name = STMPE811_GPIO_NAME,
    + .driver.owner = THIS_MODULE,
    + .probe = stmpe811_gpio_probe,
    + .remove = __devexit_p(stmpe811_gpio_remove),
    +};
    +
    +static int __init stmpe811_gpio_init(void)
    +{
    + return platform_driver_register(&stmpe811_gpio_driver);
    +}
    +
    +subsys_initcall(stmpe811_gpio_init);
    +
    +static void __exit stmpe811_gpio_exit(void)
    +{
    + platform_driver_unregister(&stmpe811_gpio_driver);
    +}
    +
    +module_exit(stmpe811_gpio_exit);
    +
    +MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
    +MODULE_DESCRIPTION("GPIO interface for STMicroelectronics STMPE811");
    +MODULE_LICENSE("GPL");
    +MODULE_ALIAS("platform:" STMPE811_GPIO_NAME);
    --
    1.7.1


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      Last update: 2010-06-14 12:35    [W:0.036 / U:0.504 seconds]
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