diff options
Diffstat (limited to 'drivers/gpio/gpio-lp873x.c')
| -rw-r--r-- | drivers/gpio/gpio-lp873x.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-lp873x.c b/drivers/gpio/gpio-lp873x.c new file mode 100644 index 000000000000..f10d49da1554 --- /dev/null +++ b/drivers/gpio/gpio-lp873x.c @@ -0,0 +1,193 @@ +/* + * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/ + * Keerthy <j-keerthy@ti.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether expressed or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License version 2 for more details. + * + * Based on the TPS65218 driver + */ + +#include <linux/gpio.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#include <linux/mfd/lp873x.h> + +#define BITS_PER_GPO 0x4 +#define LP873X_GPO_CTRL_OD 0x2 + +struct lp873x_gpio { + struct gpio_chip chip; + struct lp873x *lp873; +}; + +static int lp873x_gpio_get_direction(struct gpio_chip *chip, + unsigned int offset) +{ + /* This device is output only */ + return 0; +} + +static int lp873x_gpio_direction_input(struct gpio_chip *chip, + unsigned int offset) +{ + /* This device is output only */ + return -EINVAL; +} + +static int lp873x_gpio_direction_output(struct gpio_chip *chip, + unsigned int offset, int value) +{ + struct lp873x_gpio *gpio = gpiochip_get_data(chip); + + /* Set the initial value */ + return regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL, + BIT(offset * BITS_PER_GPO), + value ? BIT(offset * BITS_PER_GPO) : 0); +} + +static int lp873x_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + struct lp873x_gpio *gpio = gpiochip_get_data(chip); + int ret, val; + + ret = regmap_read(gpio->lp873->regmap, LP873X_REG_GPO_CTRL, &val); + if (ret < 0) + return ret; + + return val & BIT(offset * BITS_PER_GPO); +} + +static void lp873x_gpio_set(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct lp873x_gpio *gpio = gpiochip_get_data(chip); + + regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL, + BIT(offset * BITS_PER_GPO), + value ? BIT(offset * BITS_PER_GPO) : 0); +} + +static int lp873x_gpio_request(struct gpio_chip *gc, unsigned int offset) +{ + struct lp873x_gpio *gpio = gpiochip_get_data(gc); + int ret; + + switch (offset) { + case 0: + /* No MUX Set up Needed for GPO */ + break; + case 1: + /* Setup the CLKIN_PIN_SEL MUX to GPO2 */ + ret = regmap_update_bits(gpio->lp873->regmap, LP873X_REG_CONFIG, + LP873X_CONFIG_CLKIN_PIN_SEL, 0); + if (ret) + return ret; + + break; + default: + return -EINVAL; + } + + return 0; +} + +static int lp873x_gpio_set_single_ended(struct gpio_chip *gc, + unsigned int offset, + enum single_ended_mode mode) +{ + struct lp873x_gpio *gpio = gpiochip_get_data(gc); + + switch (mode) { + case LINE_MODE_OPEN_DRAIN: + return regmap_update_bits(gpio->lp873->regmap, + LP873X_REG_GPO_CTRL, + BIT(offset * BITS_PER_GPO + + LP873X_GPO_CTRL_OD), + BIT(offset * BITS_PER_GPO + + LP873X_GPO_CTRL_OD)); + case LINE_MODE_PUSH_PULL: + return regmap_update_bits(gpio->lp873->regmap, + LP873X_REG_GPO_CTRL, + BIT(offset * BITS_PER_GPO + + LP873X_GPO_CTRL_OD), 0); + default: + return -ENOTSUPP; + } +} + +static struct gpio_chip template_chip = { + .label = "lp873x-gpio", + .owner = THIS_MODULE, + .request = lp873x_gpio_request, + .get_direction = lp873x_gpio_get_direction, + .direction_input = lp873x_gpio_direction_input, + .direction_output = lp873x_gpio_direction_output, + .get = lp873x_gpio_get, + .set = lp873x_gpio_set, + .set_single_ended = lp873x_gpio_set_single_ended, + .base = -1, + .ngpio = 2, + .can_sleep = true, +}; + +static int lp873x_gpio_probe(struct platform_device *pdev) +{ + struct lp873x_gpio *gpio; + int ret; + + gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL); + if (!gpio) + return -ENOMEM; + + platform_set_drvdata(pdev, gpio); + + gpio->lp873 = dev_get_drvdata(pdev->dev.parent); + gpio->chip = template_chip; + gpio->chip.parent = gpio->lp873->dev; + + ret = gpiochip_add_data(&gpio->chip, gpio); + if (ret < 0) { + dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret); + return ret; + } + + return 0; +} + +static int lp873x_gpio_remove(struct platform_device *pdev) +{ + struct lp873x_gpio *gpio = platform_get_drvdata(pdev); + + gpiochip_remove(&gpio->chip); + + return 0; +} + +static const struct platform_device_id lp873x_gpio_id_table[] = { + { "lp873x-gpio", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(platform, lp873x_gpio_id_table); + +static struct platform_driver lp873x_gpio_driver = { + .driver = { + .name = "lp873x-gpio", + }, + .probe = lp873x_gpio_probe, + .remove = lp873x_gpio_remove, + .id_table = lp873x_gpio_id_table, +}; +module_platform_driver(lp873x_gpio_driver); + +MODULE_AUTHOR("Keerthy <j-keerthy@ti.com>"); +MODULE_DESCRIPTION("LP873X GPIO driver"); +MODULE_LICENSE("GPL v2"); |