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![Luca Ceresoli](/assets/img/avatar_default.png)
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>
131 lines
3.3 KiB
C
131 lines
3.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 2017 Texas Instruments Incorporated - https://www.ti.com/
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*
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* Author: Keerthy <j-keerthy@ti.com>
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*/
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#include <linux/gpio/consumer.h>
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#include <linux/interrupt.h>
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#include <linux/mfd/core.h>
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#include <linux/module.h>
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#include <linux/of_device.h>
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#include <linux/regmap.h>
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#include <linux/mfd/lp87565.h>
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static const struct regmap_config lp87565_regmap_config = {
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.reg_bits = 8,
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.val_bits = 8,
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.max_register = LP87565_REG_MAX,
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};
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static const struct mfd_cell lp87565_cells[] = {
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{ .name = "lp87565-q1-regulator", },
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{ .name = "lp87565-q1-gpio", },
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};
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static const struct of_device_id of_lp87565_match_table[] = {
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{ .compatible = "ti,lp87565", },
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{
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.compatible = "ti,lp87524-q1",
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.data = (void *)LP87565_DEVICE_TYPE_LP87524_Q1,
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},
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{
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.compatible = "ti,lp87565-q1",
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.data = (void *)LP87565_DEVICE_TYPE_LP87565_Q1,
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},
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{
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.compatible = "ti,lp87561-q1",
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.data = (void *)LP87565_DEVICE_TYPE_LP87561_Q1,
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},
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{}
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};
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MODULE_DEVICE_TABLE(of, of_lp87565_match_table);
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static int lp87565_probe(struct i2c_client *client,
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const struct i2c_device_id *ids)
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{
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struct lp87565 *lp87565;
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const struct of_device_id *of_id;
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int ret;
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unsigned int otpid;
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lp87565 = devm_kzalloc(&client->dev, sizeof(*lp87565), GFP_KERNEL);
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if (!lp87565)
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return -ENOMEM;
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lp87565->dev = &client->dev;
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lp87565->regmap = devm_regmap_init_i2c(client, &lp87565_regmap_config);
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if (IS_ERR(lp87565->regmap)) {
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ret = PTR_ERR(lp87565->regmap);
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dev_err(lp87565->dev,
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"Failed to initialize register map: %d\n", ret);
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return ret;
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}
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lp87565->reset_gpio = devm_gpiod_get_optional(lp87565->dev, "reset",
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GPIOD_OUT_LOW);
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if (IS_ERR(lp87565->reset_gpio)) {
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ret = PTR_ERR(lp87565->reset_gpio);
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if (ret == -EPROBE_DEFER)
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return ret;
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}
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if (lp87565->reset_gpio) {
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gpiod_set_value_cansleep(lp87565->reset_gpio, 1);
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/* The minimum assertion time is undocumented, just guess */
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usleep_range(2000, 4000);
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gpiod_set_value_cansleep(lp87565->reset_gpio, 0);
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/* Min 1.2 ms before first I2C transaction */
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usleep_range(1500, 3000);
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}
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ret = regmap_read(lp87565->regmap, LP87565_REG_OTP_REV, &otpid);
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if (ret) {
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dev_err(lp87565->dev, "Failed to read OTP ID\n");
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return ret;
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}
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lp87565->rev = otpid & LP87565_OTP_REV_OTP_ID;
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of_id = of_match_device(of_lp87565_match_table, &client->dev);
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if (of_id)
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lp87565->dev_type = (enum lp87565_device_type)of_id->data;
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i2c_set_clientdata(client, lp87565);
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return devm_mfd_add_devices(lp87565->dev, PLATFORM_DEVID_AUTO,
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lp87565_cells, ARRAY_SIZE(lp87565_cells),
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NULL, 0, NULL);
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}
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static void lp87565_shutdown(struct i2c_client *client)
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{
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struct lp87565 *lp87565 = i2c_get_clientdata(client);
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gpiod_set_value_cansleep(lp87565->reset_gpio, 1);
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}
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static const struct i2c_device_id lp87565_id_table[] = {
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{ "lp87565-q1", 0 },
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{ },
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};
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MODULE_DEVICE_TABLE(i2c, lp87565_id_table);
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static struct i2c_driver lp87565_driver = {
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.driver = {
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.name = "lp87565",
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.of_match_table = of_lp87565_match_table,
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},
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.probe = lp87565_probe,
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.shutdown = lp87565_shutdown,
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.id_table = lp87565_id_table,
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};
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module_i2c_driver(lp87565_driver);
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MODULE_AUTHOR("J Keerthy <j-keerthy@ti.com>");
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MODULE_DESCRIPTION("lp87565 chip family Multi-Function Device driver");
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MODULE_LICENSE("GPL v2");
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