mirror of
https://github.com/torvalds/linux.git
synced 2024-11-23 12:42:02 +00:00
3367ac3ea0
This adds support Richtek RT4831 core. It includes four channel WLED driver and Display Bias Voltage outputs. Signed-off-by: ChiYuan Huang <cy_huang@richtek.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
116 lines
3.0 KiB
C
116 lines
3.0 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Copyright (c) 2021 Richtek Technology Corp.
|
|
*
|
|
* Author: ChiYuan Huang <cy_huang@richtek.com>
|
|
*/
|
|
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/mfd/core.h>
|
|
#include <linux/module.h>
|
|
#include <linux/regmap.h>
|
|
|
|
#define RT4831_REG_REVISION 0x01
|
|
#define RT4831_REG_ENABLE 0x08
|
|
#define RT4831_REG_I2CPROT 0x15
|
|
|
|
#define RICHTEK_VENDOR_ID 0x03
|
|
#define RT4831_VID_MASK GENMASK(1, 0)
|
|
#define RT4831_RESET_MASK BIT(7)
|
|
#define RT4831_I2CSAFETMR_MASK BIT(0)
|
|
|
|
static const struct mfd_cell rt4831_subdevs[] = {
|
|
MFD_CELL_OF("rt4831-backlight", NULL, NULL, 0, 0, "richtek,rt4831-backlight"),
|
|
MFD_CELL_NAME("rt4831-regulator")
|
|
};
|
|
|
|
static bool rt4831_is_accessible_reg(struct device *dev, unsigned int reg)
|
|
{
|
|
if (reg >= RT4831_REG_REVISION && reg <= RT4831_REG_I2CPROT)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static const struct regmap_config rt4831_regmap_config = {
|
|
.reg_bits = 8,
|
|
.val_bits = 8,
|
|
.max_register = RT4831_REG_I2CPROT,
|
|
|
|
.readable_reg = rt4831_is_accessible_reg,
|
|
.writeable_reg = rt4831_is_accessible_reg,
|
|
};
|
|
|
|
static int rt4831_probe(struct i2c_client *client)
|
|
{
|
|
struct gpio_desc *enable_gpio;
|
|
struct regmap *regmap;
|
|
unsigned int chip_id;
|
|
int ret;
|
|
|
|
enable_gpio = devm_gpiod_get_optional(&client->dev, "enable", GPIOD_OUT_HIGH);
|
|
if (IS_ERR(enable_gpio)) {
|
|
dev_err(&client->dev, "Failed to get 'enable' GPIO\n");
|
|
return PTR_ERR(enable_gpio);
|
|
}
|
|
|
|
regmap = devm_regmap_init_i2c(client, &rt4831_regmap_config);
|
|
if (IS_ERR(regmap)) {
|
|
dev_err(&client->dev, "Failed to initialize regmap\n");
|
|
return PTR_ERR(regmap);
|
|
}
|
|
|
|
ret = regmap_read(regmap, RT4831_REG_REVISION, &chip_id);
|
|
if (ret) {
|
|
dev_err(&client->dev, "Failed to get H/W revision\n");
|
|
return ret;
|
|
}
|
|
|
|
if ((chip_id & RT4831_VID_MASK) != RICHTEK_VENDOR_ID) {
|
|
dev_err(&client->dev, "Chip vendor ID 0x%02x not matched\n", chip_id);
|
|
return -ENODEV;
|
|
}
|
|
|
|
/*
|
|
* Used to prevent the abnormal shutdown.
|
|
* If SCL/SDA both keep low for one second to reset HW.
|
|
*/
|
|
ret = regmap_update_bits(regmap, RT4831_REG_I2CPROT, RT4831_I2CSAFETMR_MASK,
|
|
RT4831_I2CSAFETMR_MASK);
|
|
if (ret) {
|
|
dev_err(&client->dev, "Failed to enable I2C safety timer\n");
|
|
return ret;
|
|
}
|
|
|
|
return devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_AUTO, rt4831_subdevs,
|
|
ARRAY_SIZE(rt4831_subdevs), NULL, 0, NULL);
|
|
}
|
|
|
|
static int rt4831_remove(struct i2c_client *client)
|
|
{
|
|
struct regmap *regmap = dev_get_regmap(&client->dev, NULL);
|
|
|
|
/* Disable WLED and DSV outputs */
|
|
return regmap_update_bits(regmap, RT4831_REG_ENABLE, RT4831_RESET_MASK, RT4831_RESET_MASK);
|
|
}
|
|
|
|
static const struct of_device_id __maybe_unused rt4831_of_match[] = {
|
|
{ .compatible = "richtek,rt4831", },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, rt4831_of_match);
|
|
|
|
static struct i2c_driver rt4831_driver = {
|
|
.driver = {
|
|
.name = "rt4831",
|
|
.of_match_table = rt4831_of_match,
|
|
},
|
|
.probe_new = rt4831_probe,
|
|
.remove = rt4831_remove,
|
|
};
|
|
module_i2c_driver(rt4831_driver);
|
|
|
|
MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
|
|
MODULE_LICENSE("GPL v2");
|