Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 1 | /* |
| 2 | * qt2160.c - Atmel AT42QT2160 Touch Sense Controller |
| 3 | * |
| 4 | * Copyright (C) 2009 Raphael Derosso Pereira <raphaelpereira@gmail.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 19 | */ |
| 20 | |
| 21 | #include <linux/kernel.h> |
| 22 | #include <linux/init.h> |
| 23 | #include <linux/module.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <linux/jiffies.h> |
| 26 | #include <linux/i2c.h> |
| 27 | #include <linux/irq.h> |
| 28 | #include <linux/interrupt.h> |
| 29 | #include <linux/input.h> |
| 30 | |
| 31 | #define QT2160_VALID_CHIPID 0x11 |
| 32 | |
| 33 | #define QT2160_CMD_CHIPID 0 |
| 34 | #define QT2160_CMD_CODEVER 1 |
| 35 | #define QT2160_CMD_GSTAT 2 |
| 36 | #define QT2160_CMD_KEYS3 3 |
| 37 | #define QT2160_CMD_KEYS4 4 |
| 38 | #define QT2160_CMD_SLIDE 5 |
| 39 | #define QT2160_CMD_GPIOS 6 |
| 40 | #define QT2160_CMD_SUBVER 7 |
| 41 | #define QT2160_CMD_CALIBRATE 10 |
| 42 | |
| 43 | #define QT2160_CYCLE_INTERVAL (2*HZ) |
| 44 | |
| 45 | static unsigned char qt2160_key2code[] = { |
| 46 | KEY_0, KEY_1, KEY_2, KEY_3, |
| 47 | KEY_4, KEY_5, KEY_6, KEY_7, |
| 48 | KEY_8, KEY_9, KEY_A, KEY_B, |
| 49 | KEY_C, KEY_D, KEY_E, KEY_F, |
| 50 | }; |
| 51 | |
| 52 | struct qt2160_data { |
| 53 | struct i2c_client *client; |
| 54 | struct input_dev *input; |
| 55 | struct delayed_work dwork; |
| 56 | spinlock_t lock; /* Protects canceling/rescheduling of dwork */ |
| 57 | unsigned short keycodes[ARRAY_SIZE(qt2160_key2code)]; |
| 58 | u16 key_matrix; |
| 59 | }; |
| 60 | |
| 61 | static int qt2160_read_block(struct i2c_client *client, |
| 62 | u8 inireg, u8 *buffer, unsigned int count) |
| 63 | { |
| 64 | int error, idx = 0; |
| 65 | |
| 66 | /* |
| 67 | * Can't use SMBus block data read. Check for I2C functionality to speed |
| 68 | * things up whenever possible. Otherwise we will be forced to read |
| 69 | * sequentially. |
| 70 | */ |
| 71 | if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { |
| 72 | |
| 73 | error = i2c_smbus_write_byte(client, inireg + idx); |
| 74 | if (error) { |
| 75 | dev_err(&client->dev, |
| 76 | "couldn't send request. Returned %d\n", error); |
| 77 | return error; |
| 78 | } |
| 79 | |
| 80 | error = i2c_master_recv(client, buffer, count); |
| 81 | if (error != count) { |
| 82 | dev_err(&client->dev, |
| 83 | "couldn't read registers. Returned %d bytes\n", error); |
| 84 | return error; |
| 85 | } |
| 86 | } else { |
| 87 | |
| 88 | while (count--) { |
| 89 | int data; |
| 90 | |
| 91 | error = i2c_smbus_write_byte(client, inireg + idx); |
| 92 | if (error) { |
| 93 | dev_err(&client->dev, |
| 94 | "couldn't send request. Returned %d\n", error); |
| 95 | return error; |
| 96 | } |
| 97 | |
| 98 | data = i2c_smbus_read_byte(client); |
| 99 | if (data < 0) { |
| 100 | dev_err(&client->dev, |
| 101 | "couldn't read register. Returned %d\n", data); |
| 102 | return data; |
| 103 | } |
| 104 | |
| 105 | buffer[idx++] = data; |
| 106 | } |
| 107 | } |
| 108 | |
| 109 | return 0; |
| 110 | } |
| 111 | |
| 112 | static int qt2160_get_key_matrix(struct qt2160_data *qt2160) |
| 113 | { |
| 114 | struct i2c_client *client = qt2160->client; |
| 115 | struct input_dev *input = qt2160->input; |
| 116 | u8 regs[6]; |
| 117 | u16 old_matrix, new_matrix; |
| 118 | int ret, i, mask; |
| 119 | |
| 120 | dev_dbg(&client->dev, "requesting keys...\n"); |
| 121 | |
| 122 | /* |
| 123 | * Read all registers from General Status Register |
| 124 | * to GPIOs register |
| 125 | */ |
| 126 | ret = qt2160_read_block(client, QT2160_CMD_GSTAT, regs, 6); |
| 127 | if (ret) { |
| 128 | dev_err(&client->dev, |
| 129 | "could not perform chip read.\n"); |
| 130 | return ret; |
| 131 | } |
| 132 | |
| 133 | old_matrix = qt2160->key_matrix; |
| 134 | qt2160->key_matrix = new_matrix = (regs[2] << 8) | regs[1]; |
| 135 | |
| 136 | mask = 0x01; |
| 137 | for (i = 0; i < 16; ++i, mask <<= 1) { |
| 138 | int keyval = new_matrix & mask; |
| 139 | |
| 140 | if ((old_matrix & mask) != keyval) { |
| 141 | input_report_key(input, qt2160->keycodes[i], keyval); |
| 142 | dev_dbg(&client->dev, "key %d %s\n", |
| 143 | i, keyval ? "pressed" : "released"); |
| 144 | } |
| 145 | } |
| 146 | |
| 147 | input_sync(input); |
| 148 | |
| 149 | return 0; |
| 150 | } |
| 151 | |
| 152 | static irqreturn_t qt2160_irq(int irq, void *_qt2160) |
| 153 | { |
| 154 | struct qt2160_data *qt2160 = _qt2160; |
| 155 | unsigned long flags; |
| 156 | |
| 157 | spin_lock_irqsave(&qt2160->lock, flags); |
| 158 | |
Tejun Heo | e7c2f96 | 2012-08-21 13:18:24 -0700 | [diff] [blame] | 159 | mod_delayed_work(system_wq, &qt2160->dwork, 0); |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 160 | |
| 161 | spin_unlock_irqrestore(&qt2160->lock, flags); |
| 162 | |
| 163 | return IRQ_HANDLED; |
| 164 | } |
| 165 | |
| 166 | static void qt2160_schedule_read(struct qt2160_data *qt2160) |
| 167 | { |
| 168 | spin_lock_irq(&qt2160->lock); |
| 169 | schedule_delayed_work(&qt2160->dwork, QT2160_CYCLE_INTERVAL); |
| 170 | spin_unlock_irq(&qt2160->lock); |
| 171 | } |
| 172 | |
| 173 | static void qt2160_worker(struct work_struct *work) |
| 174 | { |
| 175 | struct qt2160_data *qt2160 = |
| 176 | container_of(work, struct qt2160_data, dwork.work); |
| 177 | |
| 178 | dev_dbg(&qt2160->client->dev, "worker\n"); |
| 179 | |
| 180 | qt2160_get_key_matrix(qt2160); |
| 181 | |
| 182 | /* Avoid device lock up by checking every so often */ |
| 183 | qt2160_schedule_read(qt2160); |
| 184 | } |
| 185 | |
Bill Pemberton | 5298cc4 | 2012-11-23 21:38:25 -0800 | [diff] [blame] | 186 | static int qt2160_read(struct i2c_client *client, u8 reg) |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 187 | { |
| 188 | int ret; |
| 189 | |
| 190 | ret = i2c_smbus_write_byte(client, reg); |
| 191 | if (ret) { |
| 192 | dev_err(&client->dev, |
| 193 | "couldn't send request. Returned %d\n", ret); |
| 194 | return ret; |
| 195 | } |
| 196 | |
| 197 | ret = i2c_smbus_read_byte(client); |
| 198 | if (ret < 0) { |
| 199 | dev_err(&client->dev, |
| 200 | "couldn't read register. Returned %d\n", ret); |
| 201 | return ret; |
| 202 | } |
| 203 | |
| 204 | return ret; |
| 205 | } |
| 206 | |
Bill Pemberton | 5298cc4 | 2012-11-23 21:38:25 -0800 | [diff] [blame] | 207 | static int qt2160_write(struct i2c_client *client, u8 reg, u8 data) |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 208 | { |
Javier Martin | a6e8c0a | 2012-10-24 23:55:01 -0700 | [diff] [blame] | 209 | int ret; |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 210 | |
Javier Martin | a6e8c0a | 2012-10-24 23:55:01 -0700 | [diff] [blame] | 211 | ret = i2c_smbus_write_byte_data(client, reg, data); |
| 212 | if (ret < 0) |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 213 | dev_err(&client->dev, |
Javier Martin | a6e8c0a | 2012-10-24 23:55:01 -0700 | [diff] [blame] | 214 | "couldn't write data. Returned %d\n", ret); |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 215 | |
Javier Martin | a6e8c0a | 2012-10-24 23:55:01 -0700 | [diff] [blame] | 216 | return ret; |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 217 | } |
| 218 | |
| 219 | |
Bill Pemberton | 5298cc4 | 2012-11-23 21:38:25 -0800 | [diff] [blame] | 220 | static bool qt2160_identify(struct i2c_client *client) |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 221 | { |
| 222 | int id, ver, rev; |
| 223 | |
| 224 | /* Read Chid ID to check if chip is valid */ |
| 225 | id = qt2160_read(client, QT2160_CMD_CHIPID); |
| 226 | if (id != QT2160_VALID_CHIPID) { |
| 227 | dev_err(&client->dev, "ID %d not supported\n", id); |
| 228 | return false; |
| 229 | } |
| 230 | |
| 231 | /* Read chip firmware version */ |
| 232 | ver = qt2160_read(client, QT2160_CMD_CODEVER); |
| 233 | if (ver < 0) { |
| 234 | dev_err(&client->dev, "could not get firmware version\n"); |
| 235 | return false; |
| 236 | } |
| 237 | |
| 238 | /* Read chip firmware revision */ |
| 239 | rev = qt2160_read(client, QT2160_CMD_SUBVER); |
| 240 | if (rev < 0) { |
| 241 | dev_err(&client->dev, "could not get firmware revision\n"); |
| 242 | return false; |
| 243 | } |
| 244 | |
| 245 | dev_info(&client->dev, "AT42QT2160 firmware version %d.%d.%d\n", |
| 246 | ver >> 4, ver & 0xf, rev); |
| 247 | |
| 248 | return true; |
| 249 | } |
| 250 | |
Bill Pemberton | 5298cc4 | 2012-11-23 21:38:25 -0800 | [diff] [blame] | 251 | static int qt2160_probe(struct i2c_client *client, |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 252 | const struct i2c_device_id *id) |
| 253 | { |
| 254 | struct qt2160_data *qt2160; |
| 255 | struct input_dev *input; |
| 256 | int i; |
| 257 | int error; |
| 258 | |
| 259 | /* Check functionality */ |
| 260 | error = i2c_check_functionality(client->adapter, |
| 261 | I2C_FUNC_SMBUS_BYTE); |
| 262 | if (!error) { |
| 263 | dev_err(&client->dev, "%s adapter not supported\n", |
| 264 | dev_driver_string(&client->adapter->dev)); |
| 265 | return -ENODEV; |
| 266 | } |
| 267 | |
| 268 | if (!qt2160_identify(client)) |
| 269 | return -ENODEV; |
| 270 | |
| 271 | /* Chip is valid and active. Allocate structure */ |
| 272 | qt2160 = kzalloc(sizeof(struct qt2160_data), GFP_KERNEL); |
| 273 | input = input_allocate_device(); |
| 274 | if (!qt2160 || !input) { |
| 275 | dev_err(&client->dev, "insufficient memory\n"); |
| 276 | error = -ENOMEM; |
| 277 | goto err_free_mem; |
| 278 | } |
| 279 | |
| 280 | qt2160->client = client; |
| 281 | qt2160->input = input; |
| 282 | INIT_DELAYED_WORK(&qt2160->dwork, qt2160_worker); |
| 283 | spin_lock_init(&qt2160->lock); |
| 284 | |
| 285 | input->name = "AT42QT2160 Touch Sense Keyboard"; |
| 286 | input->id.bustype = BUS_I2C; |
| 287 | |
| 288 | input->keycode = qt2160->keycodes; |
| 289 | input->keycodesize = sizeof(qt2160->keycodes[0]); |
| 290 | input->keycodemax = ARRAY_SIZE(qt2160_key2code); |
| 291 | |
| 292 | __set_bit(EV_KEY, input->evbit); |
| 293 | __clear_bit(EV_REP, input->evbit); |
| 294 | for (i = 0; i < ARRAY_SIZE(qt2160_key2code); i++) { |
| 295 | qt2160->keycodes[i] = qt2160_key2code[i]; |
| 296 | __set_bit(qt2160_key2code[i], input->keybit); |
| 297 | } |
| 298 | __clear_bit(KEY_RESERVED, input->keybit); |
| 299 | |
| 300 | /* Calibrate device */ |
| 301 | error = qt2160_write(client, QT2160_CMD_CALIBRATE, 1); |
| 302 | if (error) { |
| 303 | dev_err(&client->dev, "failed to calibrate device\n"); |
| 304 | goto err_free_mem; |
| 305 | } |
| 306 | |
| 307 | if (client->irq) { |
| 308 | error = request_irq(client->irq, qt2160_irq, |
| 309 | IRQF_TRIGGER_FALLING, "qt2160", qt2160); |
| 310 | if (error) { |
| 311 | dev_err(&client->dev, |
| 312 | "failed to allocate irq %d\n", client->irq); |
| 313 | goto err_free_mem; |
| 314 | } |
| 315 | } |
| 316 | |
| 317 | error = input_register_device(qt2160->input); |
| 318 | if (error) { |
| 319 | dev_err(&client->dev, |
| 320 | "Failed to register input device\n"); |
| 321 | goto err_free_irq; |
| 322 | } |
| 323 | |
| 324 | i2c_set_clientdata(client, qt2160); |
| 325 | qt2160_schedule_read(qt2160); |
| 326 | |
| 327 | return 0; |
| 328 | |
| 329 | err_free_irq: |
| 330 | if (client->irq) |
| 331 | free_irq(client->irq, qt2160); |
| 332 | err_free_mem: |
| 333 | input_free_device(input); |
| 334 | kfree(qt2160); |
| 335 | return error; |
| 336 | } |
| 337 | |
Bill Pemberton | e2619cf | 2012-11-23 21:50:47 -0800 | [diff] [blame^] | 338 | static int qt2160_remove(struct i2c_client *client) |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 339 | { |
| 340 | struct qt2160_data *qt2160 = i2c_get_clientdata(client); |
| 341 | |
| 342 | /* Release IRQ so no queue will be scheduled */ |
| 343 | if (client->irq) |
| 344 | free_irq(client->irq, qt2160); |
| 345 | |
| 346 | cancel_delayed_work_sync(&qt2160->dwork); |
| 347 | |
| 348 | input_unregister_device(qt2160->input); |
| 349 | kfree(qt2160); |
| 350 | |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 351 | return 0; |
| 352 | } |
| 353 | |
Márton Németh | ce7b39a | 2010-01-09 23:23:02 -0800 | [diff] [blame] | 354 | static const struct i2c_device_id qt2160_idtable[] = { |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 355 | { "qt2160", 0, }, |
| 356 | { } |
| 357 | }; |
| 358 | |
| 359 | MODULE_DEVICE_TABLE(i2c, qt2160_idtable); |
| 360 | |
| 361 | static struct i2c_driver qt2160_driver = { |
| 362 | .driver = { |
| 363 | .name = "qt2160", |
| 364 | .owner = THIS_MODULE, |
| 365 | }, |
| 366 | |
| 367 | .id_table = qt2160_idtable, |
| 368 | .probe = qt2160_probe, |
Bill Pemberton | 1cb0aa8 | 2012-11-23 21:27:39 -0800 | [diff] [blame] | 369 | .remove = qt2160_remove, |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 370 | }; |
| 371 | |
Axel Lin | 1b92c1c | 2012-03-16 23:05:41 -0700 | [diff] [blame] | 372 | module_i2c_driver(qt2160_driver); |
Raphael Derosso Pereira | fde1132 | 2009-09-21 22:24:06 -0700 | [diff] [blame] | 373 | |
| 374 | MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>"); |
| 375 | MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor"); |
| 376 | MODULE_LICENSE("GPL"); |