diff options
Diffstat (limited to 'drivers/gpio/gpio-palmas.c')
| -rw-r--r-- | drivers/gpio/gpio-palmas.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-palmas.c b/drivers/gpio/gpio-palmas.c new file mode 100644 index 0000000..e3a4e56 --- /dev/null +++ b/drivers/gpio/gpio-palmas.c @@ -0,0 +1,184 @@ +/* + * TI Palma series PMIC's GPIO driver. + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * + * Author: Laxman Dewangan <ldewangan@nvidia.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/gpio.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mfd/palmas.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +struct palmas_gpio { + struct gpio_chip gpio_chip; + struct palmas *palmas; +}; + +static inline struct palmas_gpio *to_palmas_gpio(struct gpio_chip *chip) +{ + return container_of(chip, struct palmas_gpio, gpio_chip); +} + +static int palmas_gpio_get(struct gpio_chip *gc, unsigned offset) +{ + struct palmas_gpio *pg = to_palmas_gpio(gc); + struct palmas *palmas = pg->palmas; + unsigned int val; + int ret; + + ret = palmas_read(palmas, PALMAS_GPIO_BASE, PALMAS_GPIO_DATA_IN, &val); + if (ret < 0) { + dev_err(gc->dev, "GPIO_DATA_IN read failed, err = %d\n", ret); + return ret; + } + return !!(val & BIT(offset)); +} + +static void palmas_gpio_set(struct gpio_chip *gc, unsigned offset, + int value) +{ + struct palmas_gpio *pg = to_palmas_gpio(gc); + struct palmas *palmas = pg->palmas; + int ret; + + if (value) + ret = palmas_write(palmas, PALMAS_GPIO_BASE, + PALMAS_GPIO_SET_DATA_OUT, BIT(offset)); + else + ret = palmas_write(palmas, PALMAS_GPIO_BASE, + PALMAS_GPIO_CLEAR_DATA_OUT, BIT(offset)); + if (ret < 0) + dev_err(gc->dev, "%s write failed, err = %d\n", + (value) ? "GPIO_SET_DATA_OUT" : "GPIO_CLEAR_DATA_OUT", + ret); +} + +static int palmas_gpio_output(struct gpio_chip *gc, unsigned offset, + int value) +{ + struct palmas_gpio *pg = to_palmas_gpio(gc); + struct palmas *palmas = pg->palmas; + int ret; + + /* Set the initial value */ + palmas_gpio_set(gc, offset, value); + + ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, + PALMAS_GPIO_DATA_DIR, BIT(offset), BIT(offset)); + if (ret < 0) + dev_err(gc->dev, "GPIO_DATA_DIR write failed, err = %d\n", ret); + return ret; +} + +static int palmas_gpio_input(struct gpio_chip *gc, unsigned offset) +{ + struct palmas_gpio *pg = to_palmas_gpio(gc); + struct palmas *palmas = pg->palmas; + int ret; + + ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, + PALMAS_GPIO_DATA_DIR, BIT(offset), 0); + if (ret < 0) + dev_err(gc->dev, "GPIO_DATA_DIR write failed, err = %d\n", ret); + return ret; +} + +static int palmas_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct palmas_gpio *pg = to_palmas_gpio(gc); + struct palmas *palmas = pg->palmas; + + return palmas_irq_get_virq(palmas, PALMAS_GPIO_0_IRQ + offset); +} + +static int palmas_gpio_probe(struct platform_device *pdev) +{ + struct palmas *palmas = dev_get_drvdata(pdev->dev.parent); + struct palmas_platform_data *palmas_pdata; + struct palmas_gpio *palmas_gpio; + int ret; + + palmas_gpio = devm_kzalloc(&pdev->dev, + sizeof(*palmas_gpio), GFP_KERNEL); + if (!palmas_gpio) { + dev_err(&pdev->dev, "Could not allocate palmas_gpio\n"); + return -ENOMEM; + } + + palmas_gpio->palmas = palmas; + palmas_gpio->gpio_chip.owner = THIS_MODULE; + palmas_gpio->gpio_chip.label = dev_name(&pdev->dev); + palmas_gpio->gpio_chip.ngpio = 8; + palmas_gpio->gpio_chip.can_sleep = 1; + palmas_gpio->gpio_chip.direction_input = palmas_gpio_input; + palmas_gpio->gpio_chip.direction_output = palmas_gpio_output; + palmas_gpio->gpio_chip.to_irq = palmas_gpio_to_irq; + palmas_gpio->gpio_chip.set = palmas_gpio_set; + palmas_gpio->gpio_chip.get = palmas_gpio_get; + palmas_gpio->gpio_chip.dev = &pdev->dev; +#ifdef CONFIG_OF_GPIO + palmas_gpio->gpio_chip.of_node = palmas->dev->of_node; +#endif + palmas_pdata = dev_get_platdata(palmas->dev); + if (palmas_pdata && palmas_pdata->gpio_base) + palmas_gpio->gpio_chip.base = palmas_pdata->gpio_base; + else + palmas_gpio->gpio_chip.base = -1; + + ret = gpiochip_add(&palmas_gpio->gpio_chip); + if (ret < 0) { + dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, palmas_gpio); + return ret; +} + +static int palmas_gpio_remove(struct platform_device *pdev) +{ + struct palmas_gpio *palmas_gpio = platform_get_drvdata(pdev); + + return gpiochip_remove(&palmas_gpio->gpio_chip); +} + +static struct platform_driver palmas_gpio_driver = { + .driver.name = "palmas-gpio", + .driver.owner = THIS_MODULE, + .probe = palmas_gpio_probe, + .remove = palmas_gpio_remove, +}; + +static int __init palmas_gpio_init(void) +{ + return platform_driver_register(&palmas_gpio_driver); +} +subsys_initcall(palmas_gpio_init); + +static void __exit palmas_gpio_exit(void) +{ + platform_driver_unregister(&palmas_gpio_driver); +} +module_exit(palmas_gpio_exit); + +MODULE_ALIAS("platform:palmas-gpio"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_DESCRIPTION("GPIO driver for TI Palmas series PMICs"); +MODULE_LICENSE("GPL v2"); |
