diff options
Diffstat (limited to 'kernel/drivers/gpio/gpio-tps6586x.c')
-rw-r--r-- | kernel/drivers/gpio/gpio-tps6586x.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-tps6586x.c b/kernel/drivers/gpio/gpio-tps6586x.c new file mode 100644 index 000000000..9c9238e83 --- /dev/null +++ b/kernel/drivers/gpio/gpio-tps6586x.c @@ -0,0 +1,166 @@ +/* + * TI TPS6586x GPIO driver + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * Author: Laxman dewangan <ldewangan@nvidia.com> + * + * Based on tps6586x.c + * Copyright (c) 2010 CompuLab Ltd. + * Mike Rapoport <mike@compulab.co.il> + * + * 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/errno.h> +#include <linux/gpio.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mfd/tps6586x.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +/* GPIO control registers */ +#define TPS6586X_GPIOSET1 0x5d +#define TPS6586X_GPIOSET2 0x5e + +struct tps6586x_gpio { + struct gpio_chip gpio_chip; + struct device *parent; +}; + +static inline struct tps6586x_gpio *to_tps6586x_gpio(struct gpio_chip *chip) +{ + return container_of(chip, struct tps6586x_gpio, gpio_chip); +} + +static int tps6586x_gpio_get(struct gpio_chip *gc, unsigned offset) +{ + struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc); + uint8_t val; + int ret; + + ret = tps6586x_read(tps6586x_gpio->parent, TPS6586X_GPIOSET2, &val); + if (ret) + return ret; + + return !!(val & (1 << offset)); +} + +static void tps6586x_gpio_set(struct gpio_chip *gc, unsigned offset, + int value) +{ + struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc); + + tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET2, + value << offset, 1 << offset); +} + +static int tps6586x_gpio_output(struct gpio_chip *gc, unsigned offset, + int value) +{ + struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc); + uint8_t val, mask; + + tps6586x_gpio_set(gc, offset, value); + + val = 0x1 << (offset * 2); + mask = 0x3 << (offset * 2); + + return tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET1, + val, mask); +} + +static int tps6586x_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc); + + return tps6586x_irq_get_virq(tps6586x_gpio->parent, + TPS6586X_INT_PLDO_0 + offset); +} + +static int tps6586x_gpio_probe(struct platform_device *pdev) +{ + struct tps6586x_platform_data *pdata; + struct tps6586x_gpio *tps6586x_gpio; + int ret; + + pdata = dev_get_platdata(pdev->dev.parent); + tps6586x_gpio = devm_kzalloc(&pdev->dev, + sizeof(*tps6586x_gpio), GFP_KERNEL); + if (!tps6586x_gpio) + return -ENOMEM; + + tps6586x_gpio->parent = pdev->dev.parent; + + tps6586x_gpio->gpio_chip.owner = THIS_MODULE; + tps6586x_gpio->gpio_chip.label = pdev->name; + tps6586x_gpio->gpio_chip.dev = &pdev->dev; + tps6586x_gpio->gpio_chip.ngpio = 4; + tps6586x_gpio->gpio_chip.can_sleep = true; + + /* FIXME: add handling of GPIOs as dedicated inputs */ + tps6586x_gpio->gpio_chip.direction_output = tps6586x_gpio_output; + tps6586x_gpio->gpio_chip.set = tps6586x_gpio_set; + tps6586x_gpio->gpio_chip.get = tps6586x_gpio_get; + tps6586x_gpio->gpio_chip.to_irq = tps6586x_gpio_to_irq; + +#ifdef CONFIG_OF_GPIO + tps6586x_gpio->gpio_chip.of_node = pdev->dev.parent->of_node; +#endif + if (pdata && pdata->gpio_base) + tps6586x_gpio->gpio_chip.base = pdata->gpio_base; + else + tps6586x_gpio->gpio_chip.base = -1; + + ret = gpiochip_add(&tps6586x_gpio->gpio_chip); + if (ret < 0) { + dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, tps6586x_gpio); + + return ret; +} + +static int tps6586x_gpio_remove(struct platform_device *pdev) +{ + struct tps6586x_gpio *tps6586x_gpio = platform_get_drvdata(pdev); + + gpiochip_remove(&tps6586x_gpio->gpio_chip); + return 0; +} + +static struct platform_driver tps6586x_gpio_driver = { + .driver.name = "tps6586x-gpio", + .driver.owner = THIS_MODULE, + .probe = tps6586x_gpio_probe, + .remove = tps6586x_gpio_remove, +}; + +static int __init tps6586x_gpio_init(void) +{ + return platform_driver_register(&tps6586x_gpio_driver); +} +subsys_initcall(tps6586x_gpio_init); + +static void __exit tps6586x_gpio_exit(void) +{ + platform_driver_unregister(&tps6586x_gpio_driver); +} +module_exit(tps6586x_gpio_exit); + +MODULE_ALIAS("platform:tps6586x-gpio"); +MODULE_DESCRIPTION("GPIO interface for TPS6586X PMIC"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_LICENSE("GPL"); |