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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Driver for Goodix touchscreens that use the i2c-hid protocol.
  4 *
  5 * Copyright 2020 Google LLC
  6 */
  7
  8#include <linux/delay.h>
  9#include <linux/device.h>
 10#include <linux/gpio/consumer.h>
 11#include <linux/i2c.h>
 12#include <linux/kernel.h>
 13#include <linux/module.h>
 14#include <linux/of.h>
 15#include <linux/pm.h>
 16#include <linux/regulator/consumer.h>
 17
 18#include "i2c-hid.h"
 19
 20struct goodix_i2c_hid_timing_data {
 21	unsigned int post_gpio_reset_delay_ms;
 22	unsigned int post_power_delay_ms;
 23};
 24
 25struct i2c_hid_of_goodix {
 26	struct i2chid_ops ops;
 27
 28	struct regulator *vdd;
 
 29	struct gpio_desc *reset_gpio;
 
 30	const struct goodix_i2c_hid_timing_data *timings;
 31};
 32
 33static int goodix_i2c_hid_power_up(struct i2chid_ops *ops)
 34{
 35	struct i2c_hid_of_goodix *ihid_goodix =
 36		container_of(ops, struct i2c_hid_of_goodix, ops);
 37	int ret;
 38
 
 
 
 
 
 
 
 
 39	ret = regulator_enable(ihid_goodix->vdd);
 40	if (ret)
 41		return ret;
 42
 
 
 
 
 43	if (ihid_goodix->timings->post_power_delay_ms)
 44		msleep(ihid_goodix->timings->post_power_delay_ms);
 45
 46	gpiod_set_value_cansleep(ihid_goodix->reset_gpio, 0);
 47	if (ihid_goodix->timings->post_gpio_reset_delay_ms)
 48		msleep(ihid_goodix->timings->post_gpio_reset_delay_ms);
 49
 50	return 0;
 51}
 52
 53static void goodix_i2c_hid_power_down(struct i2chid_ops *ops)
 54{
 55	struct i2c_hid_of_goodix *ihid_goodix =
 56		container_of(ops, struct i2c_hid_of_goodix, ops);
 57
 58	gpiod_set_value_cansleep(ihid_goodix->reset_gpio, 1);
 
 
 
 59	regulator_disable(ihid_goodix->vdd);
 60}
 61
 62static int i2c_hid_of_goodix_probe(struct i2c_client *client,
 63				   const struct i2c_device_id *id)
 64{
 65	struct i2c_hid_of_goodix *ihid_goodix;
 66
 67	ihid_goodix = devm_kzalloc(&client->dev, sizeof(*ihid_goodix),
 68				   GFP_KERNEL);
 69	if (!ihid_goodix)
 70		return -ENOMEM;
 71
 72	ihid_goodix->ops.power_up = goodix_i2c_hid_power_up;
 73	ihid_goodix->ops.power_down = goodix_i2c_hid_power_down;
 74
 75	/* Start out with reset asserted */
 76	ihid_goodix->reset_gpio =
 77		devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
 78	if (IS_ERR(ihid_goodix->reset_gpio))
 79		return PTR_ERR(ihid_goodix->reset_gpio);
 80
 81	ihid_goodix->vdd = devm_regulator_get(&client->dev, "vdd");
 82	if (IS_ERR(ihid_goodix->vdd))
 83		return PTR_ERR(ihid_goodix->vdd);
 84
 
 
 
 
 
 
 
 85	ihid_goodix->timings = device_get_match_data(&client->dev);
 86
 87	return i2c_hid_core_probe(client, &ihid_goodix->ops, 0x0001);
 88}
 89
 90static const struct goodix_i2c_hid_timing_data goodix_gt7375p_timing_data = {
 91	.post_power_delay_ms = 10,
 92	.post_gpio_reset_delay_ms = 180,
 93};
 94
 95static const struct of_device_id goodix_i2c_hid_of_match[] = {
 96	{ .compatible = "goodix,gt7375p", .data = &goodix_gt7375p_timing_data },
 97	{ }
 98};
 99MODULE_DEVICE_TABLE(of, goodix_i2c_hid_of_match);
100
101static struct i2c_driver goodix_i2c_hid_ts_driver = {
102	.driver = {
103		.name	= "i2c_hid_of_goodix",
104		.pm	= &i2c_hid_core_pm,
105		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
106		.of_match_table = of_match_ptr(goodix_i2c_hid_of_match),
107	},
108	.probe		= i2c_hid_of_goodix_probe,
109	.remove		= i2c_hid_core_remove,
110	.shutdown	= i2c_hid_core_shutdown,
111};
112module_i2c_driver(goodix_i2c_hid_ts_driver);
113
114MODULE_AUTHOR("Douglas Anderson <dianders@chromium.org>");
115MODULE_DESCRIPTION("Goodix i2c-hid touchscreen driver");
116MODULE_LICENSE("GPL v2");
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Driver for Goodix touchscreens that use the i2c-hid protocol.
  4 *
  5 * Copyright 2020 Google LLC
  6 */
  7
  8#include <linux/delay.h>
  9#include <linux/device.h>
 10#include <linux/gpio/consumer.h>
 11#include <linux/i2c.h>
 12#include <linux/kernel.h>
 13#include <linux/module.h>
 14#include <linux/of.h>
 15#include <linux/pm.h>
 16#include <linux/regulator/consumer.h>
 17
 18#include "i2c-hid.h"
 19
 20struct goodix_i2c_hid_timing_data {
 21	unsigned int post_gpio_reset_delay_ms;
 22	unsigned int post_power_delay_ms;
 23};
 24
 25struct i2c_hid_of_goodix {
 26	struct i2chid_ops ops;
 27
 28	struct regulator *vdd;
 29	struct regulator *vddio;
 30	struct gpio_desc *reset_gpio;
 31	bool no_reset_during_suspend;
 32	const struct goodix_i2c_hid_timing_data *timings;
 33};
 34
 35static int goodix_i2c_hid_power_up(struct i2chid_ops *ops)
 36{
 37	struct i2c_hid_of_goodix *ihid_goodix =
 38		container_of(ops, struct i2c_hid_of_goodix, ops);
 39	int ret;
 40
 41	/*
 42	 * We assert reset GPIO here (instead of during power-down) to ensure
 43	 * the device will have a clean state after powering up, just like the
 44	 * normal scenarios will have.
 45	 */
 46	if (ihid_goodix->no_reset_during_suspend)
 47		gpiod_set_value_cansleep(ihid_goodix->reset_gpio, 1);
 48
 49	ret = regulator_enable(ihid_goodix->vdd);
 50	if (ret)
 51		return ret;
 52
 53	ret = regulator_enable(ihid_goodix->vddio);
 54	if (ret)
 55		return ret;
 56
 57	if (ihid_goodix->timings->post_power_delay_ms)
 58		msleep(ihid_goodix->timings->post_power_delay_ms);
 59
 60	gpiod_set_value_cansleep(ihid_goodix->reset_gpio, 0);
 61	if (ihid_goodix->timings->post_gpio_reset_delay_ms)
 62		msleep(ihid_goodix->timings->post_gpio_reset_delay_ms);
 63
 64	return 0;
 65}
 66
 67static void goodix_i2c_hid_power_down(struct i2chid_ops *ops)
 68{
 69	struct i2c_hid_of_goodix *ihid_goodix =
 70		container_of(ops, struct i2c_hid_of_goodix, ops);
 71
 72	if (!ihid_goodix->no_reset_during_suspend)
 73		gpiod_set_value_cansleep(ihid_goodix->reset_gpio, 1);
 74
 75	regulator_disable(ihid_goodix->vddio);
 76	regulator_disable(ihid_goodix->vdd);
 77}
 78
 79static int i2c_hid_of_goodix_probe(struct i2c_client *client)
 
 80{
 81	struct i2c_hid_of_goodix *ihid_goodix;
 82
 83	ihid_goodix = devm_kzalloc(&client->dev, sizeof(*ihid_goodix),
 84				   GFP_KERNEL);
 85	if (!ihid_goodix)
 86		return -ENOMEM;
 87
 88	ihid_goodix->ops.power_up = goodix_i2c_hid_power_up;
 89	ihid_goodix->ops.power_down = goodix_i2c_hid_power_down;
 90
 91	/* Start out with reset asserted */
 92	ihid_goodix->reset_gpio =
 93		devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
 94	if (IS_ERR(ihid_goodix->reset_gpio))
 95		return PTR_ERR(ihid_goodix->reset_gpio);
 96
 97	ihid_goodix->vdd = devm_regulator_get(&client->dev, "vdd");
 98	if (IS_ERR(ihid_goodix->vdd))
 99		return PTR_ERR(ihid_goodix->vdd);
100
101	ihid_goodix->vddio = devm_regulator_get(&client->dev, "mainboard-vddio");
102	if (IS_ERR(ihid_goodix->vddio))
103		return PTR_ERR(ihid_goodix->vddio);
104
105	ihid_goodix->no_reset_during_suspend =
106		of_property_read_bool(client->dev.of_node, "goodix,no-reset-during-suspend");
107
108	ihid_goodix->timings = device_get_match_data(&client->dev);
109
110	return i2c_hid_core_probe(client, &ihid_goodix->ops, 0x0001, 0);
111}
112
113static const struct goodix_i2c_hid_timing_data goodix_gt7375p_timing_data = {
114	.post_power_delay_ms = 10,
115	.post_gpio_reset_delay_ms = 180,
116};
117
118static const struct of_device_id goodix_i2c_hid_of_match[] = {
119	{ .compatible = "goodix,gt7375p", .data = &goodix_gt7375p_timing_data },
120	{ }
121};
122MODULE_DEVICE_TABLE(of, goodix_i2c_hid_of_match);
123
124static struct i2c_driver goodix_i2c_hid_ts_driver = {
125	.driver = {
126		.name	= "i2c_hid_of_goodix",
127		.pm	= &i2c_hid_core_pm,
128		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
129		.of_match_table = of_match_ptr(goodix_i2c_hid_of_match),
130	},
131	.probe		= i2c_hid_of_goodix_probe,
132	.remove		= i2c_hid_core_remove,
133	.shutdown	= i2c_hid_core_shutdown,
134};
135module_i2c_driver(goodix_i2c_hid_ts_driver);
136
137MODULE_AUTHOR("Douglas Anderson <dianders@chromium.org>");
138MODULE_DESCRIPTION("Goodix i2c-hid touchscreen driver");
139MODULE_LICENSE("GPL v2");