kernel-ark/drivers/gpio/gpio-arizona.c
Mark Brown 31ba56f274 gpiolib: Add support for Wolfson Microelectronics Arizona class devices
The Arizona class devices provide some GPIOs for use in the system. This
driver provides support for these via gpiolib. Currently interrupts are
not supported, normally the GPIOs are outputs only.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[Fold in WM5110 support patch]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-07-17 20:59:53 +02:00

164 lines
4.2 KiB
C

/*
* gpiolib support for Wolfson Arizona class devices
*
* Copyright 2012 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.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/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/mfd/arizona/core.h>
#include <linux/mfd/arizona/pdata.h>
#include <linux/mfd/arizona/registers.h>
struct arizona_gpio {
struct arizona *arizona;
struct gpio_chip gpio_chip;
};
static inline struct arizona_gpio *to_arizona_gpio(struct gpio_chip *chip)
{
return container_of(chip, struct arizona_gpio, gpio_chip);
}
static int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
{
struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
struct arizona *arizona = arizona_gpio->arizona;
return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
ARIZONA_GPN_DIR, ARIZONA_GPN_DIR);
}
static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
struct arizona *arizona = arizona_gpio->arizona;
unsigned int val;
int ret;
ret = regmap_read(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, &val);
if (ret < 0)
return ret;
if (val & ARIZONA_GPN_LVL)
return 1;
else
return 0;
}
static int arizona_gpio_direction_out(struct gpio_chip *chip,
unsigned offset, int value)
{
struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
struct arizona *arizona = arizona_gpio->arizona;
if (value)
value = ARIZONA_GPN_LVL;
return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
ARIZONA_GPN_DIR | ARIZONA_GPN_LVL, value);
}
static void arizona_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
struct arizona *arizona = arizona_gpio->arizona;
if (value)
value = ARIZONA_GPN_LVL;
regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
ARIZONA_GPN_LVL, value);
}
static struct gpio_chip template_chip = {
.label = "arizona",
.owner = THIS_MODULE,
.direction_input = arizona_gpio_direction_in,
.get = arizona_gpio_get,
.direction_output = arizona_gpio_direction_out,
.set = arizona_gpio_set,
.can_sleep = 1,
};
static int __devinit arizona_gpio_probe(struct platform_device *pdev)
{
struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
struct arizona_pdata *pdata = arizona->dev->platform_data;
struct arizona_gpio *arizona_gpio;
int ret;
arizona_gpio = devm_kzalloc(&pdev->dev, sizeof(*arizona_gpio),
GFP_KERNEL);
if (arizona_gpio == NULL)
return -ENOMEM;
arizona_gpio->arizona = arizona;
arizona_gpio->gpio_chip = template_chip;
arizona_gpio->gpio_chip.dev = &pdev->dev;
switch (arizona->type) {
case WM5102:
case WM5110:
arizona_gpio->gpio_chip.ngpio = 5;
break;
default:
dev_err(&pdev->dev, "Unknown chip variant %d\n",
arizona->type);
return -EINVAL;
}
if (pdata && pdata->gpio_base)
arizona_gpio->gpio_chip.base = pdata->gpio_base;
else
arizona_gpio->gpio_chip.base = -1;
ret = gpiochip_add(&arizona_gpio->gpio_chip);
if (ret < 0) {
dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
ret);
goto err;
}
platform_set_drvdata(pdev, arizona_gpio);
return ret;
err:
return ret;
}
static int __devexit arizona_gpio_remove(struct platform_device *pdev)
{
struct arizona_gpio *arizona_gpio = platform_get_drvdata(pdev);
return gpiochip_remove(&arizona_gpio->gpio_chip);
}
static struct platform_driver arizona_gpio_driver = {
.driver.name = "arizona-gpio",
.driver.owner = THIS_MODULE,
.probe = arizona_gpio_probe,
.remove = __devexit_p(arizona_gpio_remove),
};
module_platform_driver(arizona_gpio_driver);
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("GPIO interface for Arizona devices");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:arizona-gpio");