2 * Atmel AT42QT1070 QTouch Sensor Controller
4 * Copyright (C) 2011 Atmel
6 * Authors: Bo Shen <voice.shen@atmel.com>
8 * Base on AT42QT2160 driver by:
9 * Raphael Derosso Pereira <raphaelpereira@gmail.com>
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/i2c.h>
30 #include <linux/input.h>
31 #include <linux/slab.h>
32 #include <linux/irq.h>
33 #include <linux/interrupt.h>
34 #include <linux/jiffies.h>
35 #include <linux/delay.h>
37 /* Address for each register */
39 #define QT1070_CHIP_ID 0x2E
41 #define FW_VERSION 0x01
42 #define QT1070_FW_VERSION 0x15
44 #define DET_STATUS 0x02
46 #define KEY_STATUS 0x03
49 #define CALIBRATE_CMD 0x38
50 #define QT1070_CAL_TIME 200
54 #define QT1070_RESET_TIME 255
56 /* AT42QT1070 support up to 7 keys */
57 static const unsigned short qt1070_key2code[] = {
58 KEY_0, KEY_1, KEY_2, KEY_3,
63 struct i2c_client *client;
64 struct input_dev *input;
66 unsigned short keycodes[ARRAY_SIZE(qt1070_key2code)];
70 static int qt1070_read(struct i2c_client *client, u8 reg)
74 ret = i2c_smbus_read_byte_data(client, reg);
77 "can not read register, returned %d\n", ret);
82 static int qt1070_write(struct i2c_client *client, u8 reg, u8 data)
86 ret = i2c_smbus_write_byte_data(client, reg, data);
89 "can not write register, returned %d\n", ret);
94 static bool __devinit qt1070_identify(struct i2c_client *client)
99 id = qt1070_read(client, CHIP_ID);
100 if (id != QT1070_CHIP_ID) {
101 dev_err(&client->dev, "ID %d not supported\n", id);
105 /* Read firmware version */
106 ver = qt1070_read(client, FW_VERSION);
108 dev_err(&client->dev, "could not read the firmware version\n");
112 dev_info(&client->dev, "AT42QT1070 firmware version %x\n", ver);
117 static irqreturn_t qt1070_interrupt(int irq, void *dev_id)
119 struct qt1070_data *data = dev_id;
120 struct i2c_client *client = data->client;
121 struct input_dev *input = data->input;
123 u8 new_keys, keyval, mask = 0x01;
125 /* Read the detected status register, thus clearing interrupt */
126 qt1070_read(client, DET_STATUS);
128 /* Read which key changed */
129 new_keys = qt1070_read(client, KEY_STATUS);
131 for (i = 0; i < ARRAY_SIZE(qt1070_key2code); i++) {
132 keyval = new_keys & mask;
133 if ((data->last_keys & mask) != keyval)
134 input_report_key(input, data->keycodes[i], keyval);
139 data->last_keys = new_keys;
143 static int __devinit qt1070_probe(struct i2c_client *client,
144 const struct i2c_device_id *id)
146 struct qt1070_data *data;
147 struct input_dev *input;
151 err = i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE);
153 dev_err(&client->dev, "%s adapter not supported\n",
154 dev_driver_string(&client->adapter->dev));
159 dev_err(&client->dev, "please assign the irq to this device\n");
163 /* Identify the qt1070 chip */
164 if (!qt1070_identify(client))
167 data = kzalloc(sizeof(struct qt1070_data), GFP_KERNEL);
168 input = input_allocate_device();
169 if (!data || !input) {
170 dev_err(&client->dev, "insufficient memory\n");
175 data->client = client;
177 data->irq = client->irq;
179 input->name = "AT42QT1070 QTouch Sensor";
180 input->dev.parent = &client->dev;
181 input->id.bustype = BUS_I2C;
183 /* Add the keycode */
184 input->keycode = data->keycodes;
185 input->keycodesize = sizeof(data->keycodes[0]);
186 input->keycodemax = ARRAY_SIZE(qt1070_key2code);
188 __set_bit(EV_KEY, input->evbit);
190 for (i = 0; i < ARRAY_SIZE(qt1070_key2code); i++) {
191 data->keycodes[i] = qt1070_key2code[i];
192 __set_bit(qt1070_key2code[i], input->keybit);
195 /* Calibrate device */
196 qt1070_write(client, CALIBRATE_CMD, 1);
197 msleep(QT1070_CAL_TIME);
200 qt1070_write(client, RESET, 1);
201 msleep(QT1070_RESET_TIME);
203 err = request_threaded_irq(client->irq, NULL, qt1070_interrupt,
204 IRQF_TRIGGER_NONE | IRQF_ONESHOT,
205 client->dev.driver->name, data);
207 dev_err(&client->dev, "fail to request irq\n");
211 /* Register the input device */
212 err = input_register_device(data->input);
214 dev_err(&client->dev, "Failed to register input device\n");
218 i2c_set_clientdata(client, data);
220 /* Read to clear the chang line */
221 qt1070_read(client, DET_STATUS);
226 free_irq(client->irq, data);
228 input_free_device(input);
233 static int __devexit qt1070_remove(struct i2c_client *client)
235 struct qt1070_data *data = i2c_get_clientdata(client);
238 free_irq(client->irq, data);
240 input_unregister_device(data->input);
246 static const struct i2c_device_id qt1070_id[] = {
250 MODULE_DEVICE_TABLE(i2c, qt1070_id);
252 static struct i2c_driver qt1070_driver = {
255 .owner = THIS_MODULE,
257 .id_table = qt1070_id,
258 .probe = qt1070_probe,
259 .remove = qt1070_remove,
262 module_i2c_driver(qt1070_driver);
264 MODULE_AUTHOR("Bo Shen <voice.shen@atmel.com>");
265 MODULE_DESCRIPTION("Driver for AT42QT1070 QTouch sensor");
266 MODULE_LICENSE("GPL");