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/*
* 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 const 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 = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
if (ret < 0) {
dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
return ret;
}
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,
.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");
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