mirror of
https://github.com/torvalds/linux.git
synced 2024-11-24 21:21:41 +00:00
50e4d7a2a6
Optionally handle the NRST pin (active low reset) in order to start from a known state during boot and to shut down the chip when rebooting. Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net> Signed-off-by: Lee Jones <lee.jones@linaro.org>
132 lines
3.3 KiB
C
132 lines
3.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (C) 2017 Texas Instruments Incorporated - https://www.ti.com/
|
|
*
|
|
* Author: Keerthy <j-keerthy@ti.com>
|
|
*/
|
|
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/mfd/core.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/regmap.h>
|
|
|
|
#include <linux/mfd/lp87565.h>
|
|
|
|
static const struct regmap_config lp87565_regmap_config = {
|
|
.reg_bits = 8,
|
|
.val_bits = 8,
|
|
.max_register = LP87565_REG_MAX,
|
|
};
|
|
|
|
static const struct mfd_cell lp87565_cells[] = {
|
|
{ .name = "lp87565-q1-regulator", },
|
|
{ .name = "lp87565-q1-gpio", },
|
|
};
|
|
|
|
static const struct of_device_id of_lp87565_match_table[] = {
|
|
{ .compatible = "ti,lp87565", },
|
|
{
|
|
.compatible = "ti,lp87524-q1",
|
|
.data = (void *)LP87565_DEVICE_TYPE_LP87524_Q1,
|
|
},
|
|
{
|
|
.compatible = "ti,lp87565-q1",
|
|
.data = (void *)LP87565_DEVICE_TYPE_LP87565_Q1,
|
|
},
|
|
{
|
|
.compatible = "ti,lp87561-q1",
|
|
.data = (void *)LP87565_DEVICE_TYPE_LP87561_Q1,
|
|
},
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, of_lp87565_match_table);
|
|
|
|
static int lp87565_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *ids)
|
|
{
|
|
struct lp87565 *lp87565;
|
|
const struct of_device_id *of_id;
|
|
int ret;
|
|
unsigned int otpid;
|
|
|
|
lp87565 = devm_kzalloc(&client->dev, sizeof(*lp87565), GFP_KERNEL);
|
|
if (!lp87565)
|
|
return -ENOMEM;
|
|
|
|
lp87565->dev = &client->dev;
|
|
|
|
lp87565->regmap = devm_regmap_init_i2c(client, &lp87565_regmap_config);
|
|
if (IS_ERR(lp87565->regmap)) {
|
|
ret = PTR_ERR(lp87565->regmap);
|
|
dev_err(lp87565->dev,
|
|
"Failed to initialize register map: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
lp87565->reset_gpio = devm_gpiod_get_optional(lp87565->dev, "reset",
|
|
GPIOD_OUT_LOW);
|
|
if (IS_ERR(lp87565->reset_gpio)) {
|
|
ret = PTR_ERR(lp87565->reset_gpio);
|
|
if (ret == -EPROBE_DEFER)
|
|
return ret;
|
|
}
|
|
|
|
if (lp87565->reset_gpio) {
|
|
gpiod_set_value_cansleep(lp87565->reset_gpio, 1);
|
|
/* The minimum assertion time is undocumented, just guess */
|
|
usleep_range(2000, 4000);
|
|
|
|
gpiod_set_value_cansleep(lp87565->reset_gpio, 0);
|
|
/* Min 1.2 ms before first I2C transaction */
|
|
usleep_range(1500, 3000);
|
|
}
|
|
|
|
ret = regmap_read(lp87565->regmap, LP87565_REG_OTP_REV, &otpid);
|
|
if (ret) {
|
|
dev_err(lp87565->dev, "Failed to read OTP ID\n");
|
|
return ret;
|
|
}
|
|
|
|
lp87565->rev = otpid & LP87565_OTP_REV_OTP_ID;
|
|
|
|
of_id = of_match_device(of_lp87565_match_table, &client->dev);
|
|
if (of_id)
|
|
lp87565->dev_type = (enum lp87565_device_type)of_id->data;
|
|
|
|
i2c_set_clientdata(client, lp87565);
|
|
|
|
return devm_mfd_add_devices(lp87565->dev, PLATFORM_DEVID_AUTO,
|
|
lp87565_cells, ARRAY_SIZE(lp87565_cells),
|
|
NULL, 0, NULL);
|
|
}
|
|
|
|
static void lp87565_shutdown(struct i2c_client *client)
|
|
{
|
|
struct lp87565 *lp87565 = i2c_get_clientdata(client);
|
|
|
|
gpiod_set_value_cansleep(lp87565->reset_gpio, 1);
|
|
}
|
|
|
|
static const struct i2c_device_id lp87565_id_table[] = {
|
|
{ "lp87565-q1", 0 },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, lp87565_id_table);
|
|
|
|
static struct i2c_driver lp87565_driver = {
|
|
.driver = {
|
|
.name = "lp87565",
|
|
.of_match_table = of_lp87565_match_table,
|
|
},
|
|
.probe = lp87565_probe,
|
|
.shutdown = lp87565_shutdown,
|
|
.id_table = lp87565_id_table,
|
|
};
|
|
module_i2c_driver(lp87565_driver);
|
|
|
|
MODULE_AUTHOR("J Keerthy <j-keerthy@ti.com>");
|
|
MODULE_DESCRIPTION("lp87565 chip family Multi-Function Device driver");
|
|
MODULE_LICENSE("GPL v2");
|