diff options
Diffstat (limited to 'kernel/drivers/gpio/gpio-arizona.c')
-rw-r--r-- | kernel/drivers/gpio/gpio-arizona.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-arizona.c b/kernel/drivers/gpio/gpio-arizona.c new file mode 100644 index 000000000..052fbc8fd --- /dev/null +++ b/kernel/drivers/gpio/gpio-arizona.c @@ -0,0 +1,168 @@ +/* + * 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 = true, +}; + +static int arizona_gpio_probe(struct platform_device *pdev) +{ + struct arizona *arizona = dev_get_drvdata(pdev->dev.parent); + struct arizona_pdata *pdata = dev_get_platdata(arizona->dev); + struct arizona_gpio *arizona_gpio; + int ret; + + arizona_gpio = devm_kzalloc(&pdev->dev, sizeof(*arizona_gpio), + GFP_KERNEL); + if (!arizona_gpio) + return -ENOMEM; + + arizona_gpio->arizona = arizona; + arizona_gpio->gpio_chip = template_chip; + arizona_gpio->gpio_chip.dev = &pdev->dev; +#ifdef CONFIG_OF_GPIO + arizona_gpio->gpio_chip.of_node = arizona->dev->of_node; +#endif + + switch (arizona->type) { + case WM5102: + case WM5110: + case WM8280: + case WM8997: + 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 arizona_gpio_remove(struct platform_device *pdev) +{ + struct arizona_gpio *arizona_gpio = platform_get_drvdata(pdev); + + gpiochip_remove(&arizona_gpio->gpio_chip); + return 0; +} + +static struct platform_driver arizona_gpio_driver = { + .driver.name = "arizona-gpio", + .probe = arizona_gpio_probe, + .remove = 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"); |