/* * 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/driver.h> #include <linux/platform_device.h> #include <linux/pm_runtime.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 int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset) { struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip); struct arizona *arizona = arizona_gpio->arizona; bool persistent = gpiochip_line_is_persistent(chip, offset); bool change; int ret; ret = regmap_update_bits_check(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, ARIZONA_GPN_DIR, ARIZONA_GPN_DIR, &change); if (ret < 0) return ret; if (change && persistent) { pm_runtime_mark_last_busy(chip->parent); pm_runtime_put_autosuspend(chip->parent); } return 0; } static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset) { struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip); struct arizona *arizona = arizona_gpio->arizona; unsigned int reg, val; int ret; reg = ARIZONA_GPIO1_CTRL + offset; ret = regmap_read(arizona->regmap, reg, &val); if (ret < 0) return ret; /* Resume to read actual registers for input pins */ if (val & ARIZONA_GPN_DIR) { ret = pm_runtime_get_sync(chip->parent); if (ret < 0) { dev_err(chip->parent, "Failed to resume: %d\n", ret); return ret; } /* Register is cached, drop it to ensure a physical read */ ret = regcache_drop_region(arizona->regmap, reg, reg); if (ret < 0) { dev_err(chip->parent, "Failed to drop cache: %d\n", ret); return ret; } ret = regmap_read(arizona->regmap, reg, &val); if (ret < 0) return ret; pm_runtime_mark_last_busy(chip->parent); pm_runtime_put_autosuspend(chip->parent); } 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 = gpiochip_get_data(chip); struct arizona *arizona = arizona_gpio->arizona; bool persistent = gpiochip_line_is_persistent(chip, offset); unsigned int val; int ret; ret = regmap_read(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, &val); if (ret < 0) return ret; if ((val & ARIZONA_GPN_DIR) && persistent) { ret = pm_runtime_get_sync(chip->parent); if (ret < 0) { dev_err(chip->parent, "Failed to resume: %d\n", ret); return ret; } } 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 = gpiochip_get_data(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 const 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.parent = &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: case WM8998: case WM1814: arizona_gpio->gpio_chip.ngpio = 5; break; case WM1831: case CS47L24: arizona_gpio->gpio_chip.ngpio = 2; 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; pm_runtime_enable(&pdev->dev); ret = devm_gpiochip_add_data(&pdev->dev, &arizona_gpio->gpio_chip, arizona_gpio); if (ret < 0) { dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret); return ret; } return 0; } static struct platform_driver arizona_gpio_driver = { .driver.name = "arizona-gpio", .probe = arizona_gpio_probe, }; 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");