[PATCH v2 2/2] gpio: add driver for stmpe io-expander
Marc Kleine-Budde
mkl at pengutronix.de
Tue Sep 4 04:29:13 EDT 2012
On 09/03/2012 01:03 PM, Steffen Trumtrar wrote:
> Signed-off-by: Steffen Trumtrar <s.trumtrar at pengutronix.de>
> ---
> drivers/Kconfig | 1 +
> drivers/gpio/Kconfig | 9 +++
> drivers/gpio/Makefile | 2 +
> drivers/gpio/gpio-stmpe.c | 162 +++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 174 insertions(+)
> create mode 100644 drivers/gpio/Kconfig
> create mode 100644 drivers/gpio/Makefile
> create mode 100644 drivers/gpio/gpio-stmpe.c
>
> diff --git a/drivers/Kconfig b/drivers/Kconfig
> index 883b0e7..adf8fcd 100644
> --- a/drivers/Kconfig
> +++ b/drivers/Kconfig
> @@ -18,5 +18,6 @@ source "drivers/input/Kconfig"
> source "drivers/watchdog/Kconfig"
> source "drivers/pwm/Kconfig"
> source "drivers/dma/Kconfig"
> +source "drivers/gpio/Kconfig"
>
> endmenu
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> new file mode 100644
> index 0000000..acfd4ef
> --- /dev/null
> +++ b/drivers/gpio/Kconfig
> @@ -0,0 +1,9 @@
> +menu "GPIO "
> +
> +config STMPE_GPIO
> + depends on I2C
> + depends on GPIOLIB
> + select I2C_STMPE
> + bool "STMPE GPIO Expander"
> +
> +endmenu
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> new file mode 100644
> index 0000000..da1bc21
> --- /dev/null
> +++ b/drivers/gpio/Makefile
> @@ -0,0 +1,2 @@
> +obj-y += gpio.o
> +obj-$(CONFIG_STMPE_GPIO) += gpio-stmpe.o
> diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c
> new file mode 100644
> index 0000000..74547d9
> --- /dev/null
> +++ b/drivers/gpio/gpio-stmpe.c
> @@ -0,0 +1,162 @@
> +/*
> + * Copyright (C) 2012 Pengutronix
> + * Steffen Trumtrar <s.trumtrar at 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.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + */
> +
> +#include <common.h>
> +#include <errno.h>
> +#include <io.h>
> +#include <gpio.h>
> +#include <init.h>
> +#include <mfd/stmpe-i2c.h>
> +
> +#define GPIO_BASE 0x80
> +#define GPIO_SET (GPIO_BASE + 0x02)
> +#define GPIO_CLR (GPIO_BASE + 0x04)
> +#define GPIO_MP (GPIO_BASE + 0x06)
> +#define GPIO_SET_DIR (GPIO_BASE + 0x08)
> +#define GPIO_ED (GPIO_BASE + 0x0a)
> +#define GPIO_RE (GPIO_BASE + 0x0c)
> +#define GPIO_FE (GPIO_BASE + 0x0e)
> +#define GPIO_PULL_UP (GPIO_BASE + 0x10)
> +#define GPIO_AF (GPIO_BASE + 0x12)
> +#define GPIO_LT (GPIO_BASE + 0x16)
> +
> +#define OFFSET(gpio) (0xff & (1 << (gpio)) ? 1 : 0)
> +
> +extern void __iomem *stmpe_gpio_base[];
> +extern int stmpe_gpio_count;
Are these two used?
> +
> +struct stmpe_gpio_chip {
> + void __iomem *base;
^^^^^^^^^^^^^^^^^^
Where is it used? An i2c device doesn't have iomem?
> + struct gpio_chip chip;
> + void *ci;
why is this a void, not struct stmpe_client_info *
> +};
> +
> +static void stmpe_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value)
> +{
> + struct stmpe_gpio_chip *stmpegpio = container_of(chip, struct stmpe_gpio_chip, chip);
> + struct stmpe_client_info *ci = (struct stmpe_client_info *)stmpegpio->ci;
> + int ret;
> + u8 val;
> +
> + ci->read_reg(ci->stmpe, GPIO_MP + OFFSET(gpio), &val);
> +
> + val |= 1 << (gpio % 8);
> +
> + if (value)
> + ret = ci->write_reg(ci->stmpe, GPIO_SET + OFFSET(gpio), val);
> + else
> + ret = ci->write_reg(ci->stmpe, GPIO_CLR + OFFSET(gpio), val);
> +
> + if (ret)
> + dev_err(chip->dev, "write failed!\n");
> +}
> +
> +static int stmpe_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
> +{
> + struct stmpe_gpio_chip *stmpegpio = container_of(chip, struct stmpe_gpio_chip, chip);
> + struct stmpe_client_info *ci = (struct stmpe_client_info *)stmpegpio->ci;
> + int ret;
> + u8 val;
> +
> + ci->read_reg(ci->stmpe, GPIO_SET_DIR + OFFSET(gpio), &val);
> + val &= ~(1 << (gpio % 8));
> + ret = ci->write_reg(ci->stmpe, GPIO_SET_DIR + OFFSET(gpio), val);
> +
> + if (ret)
> + dev_err(chip->dev, "couldn't change direction. Write failed!\n");
> +
> + return 0;
> +}
> +
> +static int stmpe_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int value)
> +{
> + struct stmpe_gpio_chip *stmpegpio = container_of(chip, struct stmpe_gpio_chip, chip);
> + struct stmpe_client_info *ci = (struct stmpe_client_info *)stmpegpio->ci;
> + int ret;
> + u8 val;
> +
> + ci->read_reg(ci->stmpe, GPIO_SET_DIR + OFFSET(gpio), &val);
> + val |= 1 << (gpio % 8);
> + ret = ci->write_reg(ci->stmpe, GPIO_SET_DIR + OFFSET(gpio), val);
> +
> + stmpe_gpio_set_value(chip, gpio, value);
> +
> + if (ret)
> + dev_err(chip->dev, "couldn't change direction. Write failed!\n");
> +
> + return 0;
> +}
> +
> +static int stmpe_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
> +{
> + struct stmpe_gpio_chip *stmpegpio = container_of(chip, struct stmpe_gpio_chip, chip);
> + struct stmpe_client_info *ci = (struct stmpe_client_info *)stmpegpio->ci;
> + u8 val;
> + int ret;
> +
> + ret = ci->read_reg(ci->stmpe, GPIO_MP + OFFSET(gpio), &val);
> +
> + if (ret)
> + dev_err(chip->dev, "read failed\n");
> +
> + return val & (1 << (gpio % 8)) ? 1 : 0;
> +}
> +
> +static struct gpio_ops stmpe_gpio_ops = {
> + .direction_input = stmpe_gpio_direction_input,
> + .direction_output = stmpe_gpio_direction_output,
> + .get = stmpe_gpio_get_value,
> + .set = stmpe_gpio_set_value,
> +};
> +
> +static int stmpe_gpio_probe(struct device_d *dev)
> +{
> + struct stmpe_gpio_chip *stmpegpio;
> + struct stmpe_client_info *ci;
> +
> + stmpegpio = xzalloc(sizeof(*stmpegpio));
> +
> + stmpegpio->base = dev_request_mem_region(dev, 0);
> + stmpegpio->chip.ops = &stmpe_gpio_ops;
> + stmpegpio->ci = dev->platform_data;
> +
> + ci = (struct stmpe_client_info *)stmpegpio->ci;
> +
> + if (ci->stmpe->pdata->gpio_base)
> + stmpegpio->chip.base = ci->stmpe->pdata->gpio_base;
> + else
> + stmpegpio->chip.base = -1;
> +
> + stmpegpio->chip.ngpio = 16;
> + stmpegpio->chip.dev = dev;
> +
> + gpiochip_add(&stmpegpio->chip);
> +
> + dev_info(dev, "probed stmpe gpiochip%d with base %d\n", dev->id, stmpegpio->chip.base);
> + return 0;
> +}
> +
> +static struct driver_d stmpe_gpio_driver = {
> + .name = "stmpe-gpio",
> + .probe = stmpe_gpio_probe,
> +};
> +
> +static int stmpe_gpio_add(void)
> +{
> + register_driver(&stmpe_gpio_driver);
> + return 0;
return register_driver(&stmpe_gpio_driver);
> +}
> +coredevice_initcall(stmpe_gpio_add);
>
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
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