Loading...
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 | /*
* Driver for ChipOne icn8318 i2c touchscreen controller
*
* Copyright (c) 2015 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Red Hat authors:
* Hans de Goede <hdegoede@redhat.com>
*/
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/module.h>
#include <linux/of.h>
#define ICN8318_REG_POWER 4
#define ICN8318_REG_TOUCHDATA 16
#define ICN8318_POWER_ACTIVE 0
#define ICN8318_POWER_MONITOR 1
#define ICN8318_POWER_HIBERNATE 2
#define ICN8318_MAX_TOUCHES 5
struct icn8318_touch {
__u8 slot;
__be16 x;
__be16 y;
__u8 pressure; /* Seems more like finger width then pressure really */
__u8 event;
/* The difference between 2 and 3 is unclear */
#define ICN8318_EVENT_NO_DATA 1 /* No finger seen yet since wakeup */
#define ICN8318_EVENT_UPDATE1 2 /* New or updated coordinates */
#define ICN8318_EVENT_UPDATE2 3 /* New or updated coordinates */
#define ICN8318_EVENT_END 4 /* Finger lifted */
} __packed;
struct icn8318_touch_data {
__u8 softbutton;
__u8 touch_count;
struct icn8318_touch touches[ICN8318_MAX_TOUCHES];
} __packed;
struct icn8318_data {
struct i2c_client *client;
struct input_dev *input;
struct gpio_desc *wake_gpio;
struct touchscreen_properties prop;
};
static int icn8318_read_touch_data(struct i2c_client *client,
struct icn8318_touch_data *touch_data)
{
u8 reg = ICN8318_REG_TOUCHDATA;
struct i2c_msg msg[2] = {
{
.addr = client->addr,
.len = 1,
.buf = ®
},
{
.addr = client->addr,
.flags = I2C_M_RD,
.len = sizeof(struct icn8318_touch_data),
.buf = (u8 *)touch_data
}
};
return i2c_transfer(client->adapter, msg, 2);
}
static inline bool icn8318_touch_active(u8 event)
{
return (event == ICN8318_EVENT_UPDATE1) ||
(event == ICN8318_EVENT_UPDATE2);
}
static irqreturn_t icn8318_irq(int irq, void *dev_id)
{
struct icn8318_data *data = dev_id;
struct device *dev = &data->client->dev;
struct icn8318_touch_data touch_data;
int i, ret;
ret = icn8318_read_touch_data(data->client, &touch_data);
if (ret < 0) {
dev_err(dev, "Error reading touch data: %d\n", ret);
return IRQ_HANDLED;
}
if (touch_data.softbutton) {
/*
* Other data is invalid when a softbutton is pressed.
* This needs some extra devicetree bindings to map the icn8318
* softbutton codes to evdev codes. Currently no known devices
* use this.
*/
return IRQ_HANDLED;
}
if (touch_data.touch_count > ICN8318_MAX_TOUCHES) {
dev_warn(dev, "Too much touches %d > %d\n",
touch_data.touch_count, ICN8318_MAX_TOUCHES);
touch_data.touch_count = ICN8318_MAX_TOUCHES;
}
for (i = 0; i < touch_data.touch_count; i++) {
struct icn8318_touch *touch = &touch_data.touches[i];
bool act = icn8318_touch_active(touch->event);
input_mt_slot(data->input, touch->slot);
input_mt_report_slot_state(data->input, MT_TOOL_FINGER, act);
if (!act)
continue;
touchscreen_report_pos(data->input, &data->prop,
be16_to_cpu(touch->x),
be16_to_cpu(touch->y), true);
}
input_mt_sync_frame(data->input);
input_sync(data->input);
return IRQ_HANDLED;
}
static int icn8318_start(struct input_dev *dev)
{
struct icn8318_data *data = input_get_drvdata(dev);
enable_irq(data->client->irq);
gpiod_set_value_cansleep(data->wake_gpio, 1);
return 0;
}
static void icn8318_stop(struct input_dev *dev)
{
struct icn8318_data *data = input_get_drvdata(dev);
disable_irq(data->client->irq);
i2c_smbus_write_byte_data(data->client, ICN8318_REG_POWER,
ICN8318_POWER_HIBERNATE);
gpiod_set_value_cansleep(data->wake_gpio, 0);
}
#ifdef CONFIG_PM_SLEEP
static int icn8318_suspend(struct device *dev)
{
struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
mutex_lock(&data->input->mutex);
if (data->input->users)
icn8318_stop(data->input);
mutex_unlock(&data->input->mutex);
return 0;
}
static int icn8318_resume(struct device *dev)
{
struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
mutex_lock(&data->input->mutex);
if (data->input->users)
icn8318_start(data->input);
mutex_unlock(&data->input->mutex);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(icn8318_pm_ops, icn8318_suspend, icn8318_resume);
static int icn8318_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct icn8318_data *data;
struct input_dev *input;
int error;
if (!client->irq) {
dev_err(dev, "Error no irq specified\n");
return -EINVAL;
}
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->wake_gpio = devm_gpiod_get(dev, "wake", GPIOD_OUT_LOW);
if (IS_ERR(data->wake_gpio)) {
error = PTR_ERR(data->wake_gpio);
if (error != -EPROBE_DEFER)
dev_err(dev, "Error getting wake gpio: %d\n", error);
return error;
}
input = devm_input_allocate_device(dev);
if (!input)
return -ENOMEM;
input->name = client->name;
input->id.bustype = BUS_I2C;
input->open = icn8318_start;
input->close = icn8318_stop;
input->dev.parent = dev;
input_set_capability(input, EV_ABS, ABS_MT_POSITION_X);
input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y);
touchscreen_parse_properties(input, true, &data->prop);
if (!input_abs_get_max(input, ABS_MT_POSITION_X) ||
!input_abs_get_max(input, ABS_MT_POSITION_Y)) {
dev_err(dev, "Error touchscreen-size-x and/or -y missing\n");
return -EINVAL;
}
error = input_mt_init_slots(input, ICN8318_MAX_TOUCHES,
INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
if (error)
return error;
data->client = client;
data->input = input;
input_set_drvdata(input, data);
error = devm_request_threaded_irq(dev, client->irq, NULL, icn8318_irq,
IRQF_ONESHOT, client->name, data);
if (error) {
dev_err(dev, "Error requesting irq: %d\n", error);
return error;
}
/* Stop device till opened */
icn8318_stop(data->input);
error = input_register_device(input);
if (error)
return error;
i2c_set_clientdata(client, data);
return 0;
}
static const struct of_device_id icn8318_of_match[] = {
{ .compatible = "chipone,icn8318" },
{ }
};
MODULE_DEVICE_TABLE(of, icn8318_of_match);
/* This is useless for OF-enabled devices, but it is needed by I2C subsystem */
static const struct i2c_device_id icn8318_i2c_id[] = {
{ },
};
MODULE_DEVICE_TABLE(i2c, icn8318_i2c_id);
static struct i2c_driver icn8318_driver = {
.driver = {
.name = "chipone_icn8318",
.pm = &icn8318_pm_ops,
.of_match_table = icn8318_of_match,
},
.probe = icn8318_probe,
.id_table = icn8318_i2c_id,
};
module_i2c_driver(icn8318_driver);
MODULE_DESCRIPTION("ChipOne icn8318 I2C Touchscreen Driver");
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_LICENSE("GPL");
|