1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
// SPDX-License-Identifier: GPL-2.0
/*
* Driver for Elan touchscreens that use the i2c-hid protocol.
*
* Copyright 2020 Google LLC
*/
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/regulator/consumer.h>
#include "i2c-hid.h"
struct elan_i2c_hid_chip_data {
unsigned int post_gpio_reset_on_delay_ms;
unsigned int post_gpio_reset_off_delay_ms;
unsigned int post_power_delay_ms;
u16 hid_descriptor_address;
const char *main_supply_name;
};
struct i2c_hid_of_elan {
struct i2chid_ops ops;
struct regulator *vcc33;
struct regulator *vccio;
struct gpio_desc *reset_gpio;
const struct elan_i2c_hid_chip_data *chip_data;
};
static int elan_i2c_hid_power_up(struct i2chid_ops *ops)
{
struct i2c_hid_of_elan *ihid_elan =
container_of(ops, struct i2c_hid_of_elan, ops);
int ret;
if (ihid_elan->vcc33) {
ret = regulator_enable(ihid_elan->vcc33);
if (ret)
return ret;
}
ret = regulator_enable(ihid_elan->vccio);
if (ret) {
regulator_disable(ihid_elan->vcc33);
return ret;
}
if (ihid_elan->chip_data->post_power_delay_ms)
msleep(ihid_elan->chip_data->post_power_delay_ms);
gpiod_set_value_cansleep(ihid_elan->reset_gpio, 0);
if (ihid_elan->chip_data->post_gpio_reset_on_delay_ms)
msleep(ihid_elan->chip_data->post_gpio_reset_on_delay_ms);
return 0;
}
static void elan_i2c_hid_power_down(struct i2chid_ops *ops)
{
struct i2c_hid_of_elan *ihid_elan =
container_of(ops, struct i2c_hid_of_elan, ops);
gpiod_set_value_cansleep(ihid_elan->reset_gpio, 1);
if (ihid_elan->chip_data->post_gpio_reset_off_delay_ms)
msleep(ihid_elan->chip_data->post_gpio_reset_off_delay_ms);
regulator_disable(ihid_elan->vccio);
if (ihid_elan->vcc33)
regulator_disable(ihid_elan->vcc33);
}
static int i2c_hid_of_elan_probe(struct i2c_client *client)
{
struct i2c_hid_of_elan *ihid_elan;
ihid_elan = devm_kzalloc(&client->dev, sizeof(*ihid_elan), GFP_KERNEL);
if (!ihid_elan)
return -ENOMEM;
ihid_elan->ops.power_up = elan_i2c_hid_power_up;
ihid_elan->ops.power_down = elan_i2c_hid_power_down;
/* Start out with reset asserted */
ihid_elan->reset_gpio =
devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(ihid_elan->reset_gpio))
return PTR_ERR(ihid_elan->reset_gpio);
ihid_elan->vccio = devm_regulator_get(&client->dev, "vccio");
if (IS_ERR(ihid_elan->vccio))
return PTR_ERR(ihid_elan->vccio);
ihid_elan->chip_data = device_get_match_data(&client->dev);
if (ihid_elan->chip_data->main_supply_name) {
ihid_elan->vcc33 = devm_regulator_get(&client->dev,
ihid_elan->chip_data->main_supply_name);
if (IS_ERR(ihid_elan->vcc33))
return PTR_ERR(ihid_elan->vcc33);
}
return i2c_hid_core_probe(client, &ihid_elan->ops,
ihid_elan->chip_data->hid_descriptor_address, 0);
}
static const struct elan_i2c_hid_chip_data elan_ekth6915_chip_data = {
.post_power_delay_ms = 1,
.post_gpio_reset_on_delay_ms = 300,
.hid_descriptor_address = 0x0001,
.main_supply_name = "vcc33",
};
static const struct elan_i2c_hid_chip_data ilitek_ili9882t_chip_data = {
.post_power_delay_ms = 1,
.post_gpio_reset_on_delay_ms = 200,
.post_gpio_reset_off_delay_ms = 65,
.hid_descriptor_address = 0x0001,
/*
* this touchscreen is tightly integrated with the panel and assumes
* that the relevant power rails (other than the IO rail) have already
* been turned on by the panel driver because we're a panel follower.
*/
.main_supply_name = NULL,
};
static const struct of_device_id elan_i2c_hid_of_match[] = {
{ .compatible = "elan,ekth6915", .data = &elan_ekth6915_chip_data },
{ .compatible = "ilitek,ili9882t", .data = &ilitek_ili9882t_chip_data },
{ }
};
MODULE_DEVICE_TABLE(of, elan_i2c_hid_of_match);
static struct i2c_driver elan_i2c_hid_ts_driver = {
.driver = {
.name = "i2c_hid_of_elan",
.pm = &i2c_hid_core_pm,
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.of_match_table = of_match_ptr(elan_i2c_hid_of_match),
},
.probe = i2c_hid_of_elan_probe,
.remove = i2c_hid_core_remove,
.shutdown = i2c_hid_core_shutdown,
};
module_i2c_driver(elan_i2c_hid_ts_driver);
MODULE_AUTHOR("Douglas Anderson <dianders@chromium.org>");
MODULE_DESCRIPTION("Elan i2c-hid touchscreen driver");
MODULE_LICENSE("GPL");
|
