2 * Driver for Goodix Touchscreens
4 * Copyright (c) 2014 Red Hat Inc.
6 * This code is based on gt9xx.c authored by andrew@goodix.com:
8 * 2010 - 2012 Goodix Technology.
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the Free
14 * Software Foundation; version 2 of the License.
17 #include <linux/kernel.h>
18 #include <linux/i2c.h>
19 #include <linux/input.h>
20 #include <linux/input/mt.h>
21 #include <linux/module.h>
22 #include <linux/delay.h>
23 #include <linux/irq.h>
24 #include <linux/interrupt.h>
25 #include <linux/slab.h>
26 #include <asm/unaligned.h>
28 struct goodix_ts_data {
29 struct i2c_client *client;
30 struct input_dev *input_dev;
33 unsigned int max_touch_num;
34 unsigned int int_trigger_type;
37 #define GOODIX_MAX_HEIGHT 4096
38 #define GOODIX_MAX_WIDTH 4096
39 #define GOODIX_INT_TRIGGER 1
40 #define GOODIX_CONTACT_SIZE 8
41 #define GOODIX_MAX_CONTACTS 10
43 #define GOODIX_CONFIG_MAX_LENGTH 240
45 /* Register defines */
46 #define GOODIX_READ_COOR_ADDR 0x814E
47 #define GOODIX_REG_CONFIG_DATA 0x8047
48 #define GOODIX_REG_VERSION 0x8140
50 #define RESOLUTION_LOC 1
53 static const unsigned long goodix_irq_flags[] = {
55 IRQ_TYPE_EDGE_FALLING,
61 * goodix_i2c_read - read data from a register of the i2c slave device.
63 * @client: i2c device.
64 * @reg: the register to read from.
65 * @buf: raw write data buffer.
66 * @len: length of the buffer to write
68 static int goodix_i2c_read(struct i2c_client *client,
69 u16 reg, u8 *buf, int len)
71 struct i2c_msg msgs[2];
72 u16 wbuf = cpu_to_be16(reg);
76 msgs[0].addr = client->addr;
78 msgs[0].buf = (u8 *) &wbuf;
80 msgs[1].flags = I2C_M_RD;
81 msgs[1].addr = client->addr;
85 ret = i2c_transfer(client->adapter, msgs, 2);
86 return ret < 0 ? ret : (ret != ARRAY_SIZE(msgs) ? -EIO : 0);
89 static int goodix_ts_read_input_report(struct goodix_ts_data *ts, u8 *data)
94 error = goodix_i2c_read(ts->client, GOODIX_READ_COOR_ADDR, data,
95 GOODIX_CONTACT_SIZE + 1);
97 dev_err(&ts->client->dev, "I2C transfer error: %d\n", error);
101 touch_num = data[0] & 0x0f;
102 if (touch_num > GOODIX_MAX_CONTACTS)
106 data += 1 + GOODIX_CONTACT_SIZE;
107 error = goodix_i2c_read(ts->client,
108 GOODIX_READ_COOR_ADDR +
109 1 + GOODIX_CONTACT_SIZE,
111 GOODIX_CONTACT_SIZE * (touch_num - 1));
119 static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
121 int id = coor_data[0] & 0x0F;
122 int input_x = get_unaligned_le16(&coor_data[1]);
123 int input_y = get_unaligned_le16(&coor_data[3]);
124 int input_w = get_unaligned_le16(&coor_data[5]);
126 input_mt_slot(ts->input_dev, id);
127 input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
128 input_report_abs(ts->input_dev, ABS_MT_POSITION_X, input_x);
129 input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, input_y);
130 input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, input_w);
131 input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);
135 * goodix_process_events - Process incoming events
137 * @ts: our goodix_ts_data pointer
139 * Called when the IRQ is triggered. Read the current device state, and push
140 * the input events to the user space.
142 static void goodix_process_events(struct goodix_ts_data *ts)
144 u8 point_data[1 + GOODIX_CONTACT_SIZE * GOODIX_MAX_CONTACTS];
148 touch_num = goodix_ts_read_input_report(ts, point_data);
152 for (i = 0; i < touch_num; i++)
153 goodix_ts_report_touch(ts,
154 &point_data[1 + GOODIX_CONTACT_SIZE * i]);
156 input_mt_sync_frame(ts->input_dev);
157 input_sync(ts->input_dev);
161 * goodix_ts_irq_handler - The IRQ handler
163 * @irq: interrupt number.
164 * @dev_id: private data pointer.
166 static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
168 static const u8 end_cmd[] = {
169 GOODIX_READ_COOR_ADDR >> 8,
170 GOODIX_READ_COOR_ADDR & 0xff,
173 struct goodix_ts_data *ts = dev_id;
175 goodix_process_events(ts);
177 if (i2c_master_send(ts->client, end_cmd, sizeof(end_cmd)) < 0)
178 dev_err(&ts->client->dev, "I2C write end_cmd error\n");
184 * goodix_read_config - Read the embedded configuration of the panel
186 * @ts: our goodix_ts_data pointer
188 * Must be called during probe
190 static void goodix_read_config(struct goodix_ts_data *ts)
192 u8 config[GOODIX_CONFIG_MAX_LENGTH];
195 error = goodix_i2c_read(ts->client, GOODIX_REG_CONFIG_DATA,
197 GOODIX_CONFIG_MAX_LENGTH);
199 dev_warn(&ts->client->dev,
200 "Error reading config (%d), using defaults\n",
202 ts->abs_x_max = GOODIX_MAX_WIDTH;
203 ts->abs_y_max = GOODIX_MAX_HEIGHT;
204 ts->int_trigger_type = GOODIX_INT_TRIGGER;
208 ts->abs_x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
209 ts->abs_y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
210 ts->int_trigger_type = (config[TRIGGER_LOC]) & 0x03;
211 if (!ts->abs_x_max || !ts->abs_y_max) {
212 dev_err(&ts->client->dev,
213 "Invalid config, using defaults\n");
214 ts->abs_x_max = GOODIX_MAX_WIDTH;
215 ts->abs_y_max = GOODIX_MAX_HEIGHT;
221 * goodix_read_version - Read goodix touchscreen version
223 * @client: the i2c client
224 * @version: output buffer containing the version on success
226 static int goodix_read_version(struct i2c_client *client, u16 *version)
231 error = goodix_i2c_read(client, GOODIX_REG_VERSION, buf, sizeof(buf));
233 dev_err(&client->dev, "read version failed: %d\n", error);
238 *version = get_unaligned_le16(&buf[4]);
240 dev_info(&client->dev, "IC VERSION: %6ph\n", buf);
246 * goodix_i2c_test - I2C test function to check if the device answers.
248 * @client: the i2c client
250 static int goodix_i2c_test(struct i2c_client *client)
256 while (retry++ < 2) {
257 error = goodix_i2c_read(client, GOODIX_REG_CONFIG_DATA,
262 dev_err(&client->dev, "i2c test failed attempt %d: %d\n",
271 * goodix_request_input_dev - Allocate, populate and register the input device
273 * @ts: our goodix_ts_data pointer
275 * Must be called during probe
277 static int goodix_request_input_dev(struct goodix_ts_data *ts)
281 ts->input_dev = devm_input_allocate_device(&ts->client->dev);
282 if (!ts->input_dev) {
283 dev_err(&ts->client->dev, "Failed to allocate input device.");
287 ts->input_dev->evbit[0] = BIT_MASK(EV_SYN) |
291 input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X, 0,
292 ts->abs_x_max, 0, 0);
293 input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y, 0,
294 ts->abs_y_max, 0, 0);
295 input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
296 input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
298 input_mt_init_slots(ts->input_dev, GOODIX_MAX_CONTACTS,
299 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
301 ts->input_dev->name = "Goodix Capacitive TouchScreen";
302 ts->input_dev->phys = "input/ts";
303 ts->input_dev->id.bustype = BUS_I2C;
304 ts->input_dev->id.vendor = 0x0416;
305 ts->input_dev->id.product = 0x1001;
306 ts->input_dev->id.version = 10427;
308 error = input_register_device(ts->input_dev);
310 dev_err(&ts->client->dev,
311 "Failed to register input device: %d", error);
318 static int goodix_ts_probe(struct i2c_client *client,
319 const struct i2c_device_id *id)
321 struct goodix_ts_data *ts;
322 unsigned long irq_flags;
326 dev_dbg(&client->dev, "I2C Address: 0x%02x\n", client->addr);
328 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
329 dev_err(&client->dev, "I2C check functionality failed.\n");
333 ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
338 i2c_set_clientdata(client, ts);
340 error = goodix_i2c_test(client);
342 dev_err(&client->dev, "I2C communication failure: %d\n", error);
346 error = goodix_read_version(client, &version_info);
348 dev_err(&client->dev, "Read version failed.\n");
352 goodix_read_config(ts);
354 error = goodix_request_input_dev(ts);
358 irq_flags = goodix_irq_flags[ts->int_trigger_type] | IRQF_ONESHOT;
359 error = devm_request_threaded_irq(&ts->client->dev, client->irq,
360 NULL, goodix_ts_irq_handler,
361 irq_flags, client->name, ts);
363 dev_err(&client->dev, "request IRQ failed: %d\n", error);
370 static const struct i2c_device_id goodix_ts_id[] = {
371 { "GDIX1001:00", 0 },
375 static const struct acpi_device_id goodix_acpi_match[] = {
379 MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
381 static struct i2c_driver goodix_ts_driver = {
382 .probe = goodix_ts_probe,
383 .id_table = goodix_ts_id,
386 .owner = THIS_MODULE,
387 .acpi_match_table = goodix_acpi_match,
390 module_i2c_driver(goodix_ts_driver);
392 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
393 MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
394 MODULE_DESCRIPTION("Goodix touchscreen driver");
395 MODULE_LICENSE("GPL v2");