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v3.15
  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/leds.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#define QT2160_CMD_DRIVE_X    70
 43#define QT2160_CMD_PWMEN_X    74
 44#define QT2160_CMD_PWM_DUTY   76
 45
 46#define QT2160_NUM_LEDS_X	8
 47
 48#define QT2160_CYCLE_INTERVAL	(2*HZ)
 49
 50static unsigned char qt2160_key2code[] = {
 51	KEY_0, KEY_1, KEY_2, KEY_3,
 52	KEY_4, KEY_5, KEY_6, KEY_7,
 53	KEY_8, KEY_9, KEY_A, KEY_B,
 54	KEY_C, KEY_D, KEY_E, KEY_F,
 55};
 56
 57#ifdef CONFIG_LEDS_CLASS
 58struct qt2160_led {
 59	struct qt2160_data *qt2160;
 60	struct led_classdev cdev;
 61	struct work_struct work;
 62	char name[32];
 63	int id;
 64	enum led_brightness new_brightness;
 65};
 66#endif
 67
 68struct qt2160_data {
 69	struct i2c_client *client;
 70	struct input_dev *input;
 71	struct delayed_work dwork;
 72	spinlock_t lock;        /* Protects canceling/rescheduling of dwork */
 73	unsigned short keycodes[ARRAY_SIZE(qt2160_key2code)];
 74	u16 key_matrix;
 75#ifdef CONFIG_LEDS_CLASS
 76	struct qt2160_led leds[QT2160_NUM_LEDS_X];
 77	struct mutex led_lock;
 78#endif
 79};
 80
 81static int qt2160_read(struct i2c_client *client, u8 reg);
 82static int qt2160_write(struct i2c_client *client, u8 reg, u8 data);
 83
 84#ifdef CONFIG_LEDS_CLASS
 85
 86static void qt2160_led_work(struct work_struct *work)
 87{
 88	struct qt2160_led *led = container_of(work, struct qt2160_led, work);
 89	struct qt2160_data *qt2160 = led->qt2160;
 90	struct i2c_client *client = qt2160->client;
 91	int value = led->new_brightness;
 92	u32 drive, pwmen;
 93
 94	mutex_lock(&qt2160->led_lock);
 95
 96	drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
 97	pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
 98	if (value != LED_OFF) {
 99		drive |= (1 << led->id);
100		pwmen |= (1 << led->id);
101
102	} else {
103		drive &= ~(1 << led->id);
104		pwmen &= ~(1 << led->id);
105	}
106	qt2160_write(client, QT2160_CMD_DRIVE_X, drive);
107	qt2160_write(client, QT2160_CMD_PWMEN_X, pwmen);
108
109	/*
110	 * Changing this register will change the brightness
111	 * of every LED in the qt2160. It's a HW limitation.
112	 */
113	if (value != LED_OFF)
114		qt2160_write(client, QT2160_CMD_PWM_DUTY, value);
115
116	mutex_unlock(&qt2160->led_lock);
117}
118
119static void qt2160_led_set(struct led_classdev *cdev,
120			   enum led_brightness value)
121{
122	struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
123
124	led->new_brightness = value;
125	schedule_work(&led->work);
126}
127
128#endif /* CONFIG_LEDS_CLASS */
129
130static int qt2160_read_block(struct i2c_client *client,
131			     u8 inireg, u8 *buffer, unsigned int count)
132{
133	int error, idx = 0;
134
135	/*
136	 * Can't use SMBus block data read. Check for I2C functionality to speed
137	 * things up whenever possible. Otherwise we will be forced to read
138	 * sequentially.
139	 */
140	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))	{
141
142		error = i2c_smbus_write_byte(client, inireg + idx);
143		if (error) {
144			dev_err(&client->dev,
145				"couldn't send request. Returned %d\n", error);
146			return error;
147		}
148
149		error = i2c_master_recv(client, buffer, count);
150		if (error != count) {
151			dev_err(&client->dev,
152				"couldn't read registers. Returned %d bytes\n", error);
153			return error;
154		}
155	} else {
156
157		while (count--) {
158			int data;
159
160			error = i2c_smbus_write_byte(client, inireg + idx);
161			if (error) {
162				dev_err(&client->dev,
163					"couldn't send request. Returned %d\n", error);
164				return error;
165			}
166
167			data = i2c_smbus_read_byte(client);
168			if (data < 0) {
169				dev_err(&client->dev,
170					"couldn't read register. Returned %d\n", data);
171				return data;
172			}
173
174			buffer[idx++] = data;
175		}
176	}
177
178	return 0;
179}
180
181static int qt2160_get_key_matrix(struct qt2160_data *qt2160)
182{
183	struct i2c_client *client = qt2160->client;
184	struct input_dev *input = qt2160->input;
185	u8 regs[6];
186	u16 old_matrix, new_matrix;
187	int ret, i, mask;
188
189	dev_dbg(&client->dev, "requesting keys...\n");
190
191	/*
192	 * Read all registers from General Status Register
193	 * to GPIOs register
194	 */
195	ret = qt2160_read_block(client, QT2160_CMD_GSTAT, regs, 6);
196	if (ret) {
197		dev_err(&client->dev,
198			"could not perform chip read.\n");
199		return ret;
200	}
201
202	old_matrix = qt2160->key_matrix;
203	qt2160->key_matrix = new_matrix = (regs[2] << 8) | regs[1];
204
205	mask = 0x01;
206	for (i = 0; i < 16; ++i, mask <<= 1) {
207		int keyval = new_matrix & mask;
208
209		if ((old_matrix & mask) != keyval) {
210			input_report_key(input, qt2160->keycodes[i], keyval);
211			dev_dbg(&client->dev, "key %d %s\n",
212				i, keyval ? "pressed" : "released");
213		}
214	}
215
216	input_sync(input);
217
218	return 0;
219}
220
221static irqreturn_t qt2160_irq(int irq, void *_qt2160)
222{
223	struct qt2160_data *qt2160 = _qt2160;
224	unsigned long flags;
225
226	spin_lock_irqsave(&qt2160->lock, flags);
227
228	mod_delayed_work(system_wq, &qt2160->dwork, 0);
229
230	spin_unlock_irqrestore(&qt2160->lock, flags);
231
232	return IRQ_HANDLED;
233}
234
235static void qt2160_schedule_read(struct qt2160_data *qt2160)
236{
237	spin_lock_irq(&qt2160->lock);
238	schedule_delayed_work(&qt2160->dwork, QT2160_CYCLE_INTERVAL);
239	spin_unlock_irq(&qt2160->lock);
240}
241
242static void qt2160_worker(struct work_struct *work)
243{
244	struct qt2160_data *qt2160 =
245		container_of(work, struct qt2160_data, dwork.work);
246
247	dev_dbg(&qt2160->client->dev, "worker\n");
248
249	qt2160_get_key_matrix(qt2160);
250
251	/* Avoid device lock up by checking every so often */
252	qt2160_schedule_read(qt2160);
253}
254
255static int qt2160_read(struct i2c_client *client, u8 reg)
256{
257	int ret;
258
259	ret = i2c_smbus_write_byte(client, reg);
260	if (ret) {
261		dev_err(&client->dev,
262			"couldn't send request. Returned %d\n", ret);
263		return ret;
264	}
265
266	ret = i2c_smbus_read_byte(client);
267	if (ret < 0) {
268		dev_err(&client->dev,
269			"couldn't read register. Returned %d\n", ret);
270		return ret;
271	}
272
273	return ret;
274}
275
276static int qt2160_write(struct i2c_client *client, u8 reg, u8 data)
277{
278	int ret;
279
280	ret = i2c_smbus_write_byte_data(client, reg, data);
281	if (ret < 0)
282		dev_err(&client->dev,
283			"couldn't write data. Returned %d\n", ret);
284
285	return ret;
286}
287
288#ifdef CONFIG_LEDS_CLASS
289
290static int qt2160_register_leds(struct qt2160_data *qt2160)
291{
292	struct i2c_client *client = qt2160->client;
293	int ret;
294	int i;
295
296	mutex_init(&qt2160->led_lock);
297
298	for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
299		struct qt2160_led *led = &qt2160->leds[i];
300
301		snprintf(led->name, sizeof(led->name), "qt2160:x%d", i);
302		led->cdev.name = led->name;
303		led->cdev.brightness_set = qt2160_led_set;
304		led->cdev.brightness = LED_OFF;
305		led->id = i;
306		led->qt2160 = qt2160;
307
308		INIT_WORK(&led->work, qt2160_led_work);
309
310		ret = led_classdev_register(&client->dev, &led->cdev);
311		if (ret < 0)
312			return ret;
313	}
314
315	/* Tur off LEDs */
316	qt2160_write(client, QT2160_CMD_DRIVE_X, 0);
317	qt2160_write(client, QT2160_CMD_PWMEN_X, 0);
318	qt2160_write(client, QT2160_CMD_PWM_DUTY, 0);
319
320	return 0;
321}
322
323static void qt2160_unregister_leds(struct qt2160_data *qt2160)
324{
325	int i;
326
327	for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
328		led_classdev_unregister(&qt2160->leds[i].cdev);
329		cancel_work_sync(&qt2160->leds[i].work);
330	}
331}
332
333#else
334
335static inline int qt2160_register_leds(struct qt2160_data *qt2160)
336{
337	return 0;
338}
339
340static inline void qt2160_unregister_leds(struct qt2160_data *qt2160)
341{
342}
343
344#endif
345
346static bool qt2160_identify(struct i2c_client *client)
347{
348	int id, ver, rev;
349
350	/* Read Chid ID to check if chip is valid */
351	id = qt2160_read(client, QT2160_CMD_CHIPID);
352	if (id != QT2160_VALID_CHIPID) {
353		dev_err(&client->dev, "ID %d not supported\n", id);
354		return false;
355	}
356
357	/* Read chip firmware version */
358	ver = qt2160_read(client, QT2160_CMD_CODEVER);
359	if (ver < 0) {
360		dev_err(&client->dev, "could not get firmware version\n");
361		return false;
362	}
363
364	/* Read chip firmware revision */
365	rev = qt2160_read(client, QT2160_CMD_SUBVER);
366	if (rev < 0) {
367		dev_err(&client->dev, "could not get firmware revision\n");
368		return false;
369	}
370
371	dev_info(&client->dev, "AT42QT2160 firmware version %d.%d.%d\n",
372			ver >> 4, ver & 0xf, rev);
373
374	return true;
375}
376
377static int qt2160_probe(struct i2c_client *client,
378			const struct i2c_device_id *id)
379{
380	struct qt2160_data *qt2160;
381	struct input_dev *input;
382	int i;
383	int error;
384
385	/* Check functionality */
386	error = i2c_check_functionality(client->adapter,
387			I2C_FUNC_SMBUS_BYTE);
388	if (!error) {
389		dev_err(&client->dev, "%s adapter not supported\n",
390				dev_driver_string(&client->adapter->dev));
391		return -ENODEV;
392	}
393
394	if (!qt2160_identify(client))
395		return -ENODEV;
396
397	/* Chip is valid and active. Allocate structure */
398	qt2160 = kzalloc(sizeof(struct qt2160_data), GFP_KERNEL);
399	input = input_allocate_device();
400	if (!qt2160 || !input) {
401		dev_err(&client->dev, "insufficient memory\n");
402		error = -ENOMEM;
403		goto err_free_mem;
404	}
405
406	qt2160->client = client;
407	qt2160->input = input;
408	INIT_DELAYED_WORK(&qt2160->dwork, qt2160_worker);
409	spin_lock_init(&qt2160->lock);
410
411	input->name = "AT42QT2160 Touch Sense Keyboard";
412	input->id.bustype = BUS_I2C;
413
414	input->keycode = qt2160->keycodes;
415	input->keycodesize = sizeof(qt2160->keycodes[0]);
416	input->keycodemax = ARRAY_SIZE(qt2160_key2code);
417
418	__set_bit(EV_KEY, input->evbit);
419	__clear_bit(EV_REP, input->evbit);
420	for (i = 0; i < ARRAY_SIZE(qt2160_key2code); i++) {
421		qt2160->keycodes[i] = qt2160_key2code[i];
422		__set_bit(qt2160_key2code[i], input->keybit);
423	}
424	__clear_bit(KEY_RESERVED, input->keybit);
425
426	/* Calibrate device */
427	error = qt2160_write(client, QT2160_CMD_CALIBRATE, 1);
428	if (error) {
429		dev_err(&client->dev, "failed to calibrate device\n");
430		goto err_free_mem;
431	}
432
433	if (client->irq) {
434		error = request_irq(client->irq, qt2160_irq,
435				    IRQF_TRIGGER_FALLING, "qt2160", qt2160);
436		if (error) {
437			dev_err(&client->dev,
438				"failed to allocate irq %d\n", client->irq);
439			goto err_free_mem;
440		}
441	}
442
443	error = qt2160_register_leds(qt2160);
444	if (error) {
445		dev_err(&client->dev, "Failed to register leds\n");
446		goto err_free_irq;
447	}
448
449	error = input_register_device(qt2160->input);
450	if (error) {
451		dev_err(&client->dev,
452			"Failed to register input device\n");
453		goto err_unregister_leds;
454	}
455
456	i2c_set_clientdata(client, qt2160);
457	qt2160_schedule_read(qt2160);
458
459	return 0;
460
461err_unregister_leds:
462	qt2160_unregister_leds(qt2160);
463err_free_irq:
464	if (client->irq)
465		free_irq(client->irq, qt2160);
466err_free_mem:
467	input_free_device(input);
468	kfree(qt2160);
469	return error;
470}
471
472static int qt2160_remove(struct i2c_client *client)
473{
474	struct qt2160_data *qt2160 = i2c_get_clientdata(client);
475
476	qt2160_unregister_leds(qt2160);
477
478	/* Release IRQ so no queue will be scheduled */
479	if (client->irq)
480		free_irq(client->irq, qt2160);
481
482	cancel_delayed_work_sync(&qt2160->dwork);
483
484	input_unregister_device(qt2160->input);
485	kfree(qt2160);
486
487	return 0;
488}
489
490static const struct i2c_device_id qt2160_idtable[] = {
491	{ "qt2160", 0, },
492	{ }
493};
494
495MODULE_DEVICE_TABLE(i2c, qt2160_idtable);
496
497static struct i2c_driver qt2160_driver = {
498	.driver = {
499		.name	= "qt2160",
500		.owner  = THIS_MODULE,
501	},
502
503	.id_table	= qt2160_idtable,
504	.probe		= qt2160_probe,
505	.remove		= qt2160_remove,
506};
507
508module_i2c_driver(qt2160_driver);
509
510MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>");
511MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor");
512MODULE_LICENSE("GPL");
v4.17
  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/leds.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#define QT2160_CMD_DRIVE_X    70
 43#define QT2160_CMD_PWMEN_X    74
 44#define QT2160_CMD_PWM_DUTY   76
 45
 46#define QT2160_NUM_LEDS_X	8
 47
 48#define QT2160_CYCLE_INTERVAL	(2*HZ)
 49
 50static unsigned char qt2160_key2code[] = {
 51	KEY_0, KEY_1, KEY_2, KEY_3,
 52	KEY_4, KEY_5, KEY_6, KEY_7,
 53	KEY_8, KEY_9, KEY_A, KEY_B,
 54	KEY_C, KEY_D, KEY_E, KEY_F,
 55};
 56
 57#ifdef CONFIG_LEDS_CLASS
 58struct qt2160_led {
 59	struct qt2160_data *qt2160;
 60	struct led_classdev cdev;
 61	struct work_struct work;
 62	char name[32];
 63	int id;
 64	enum led_brightness new_brightness;
 65};
 66#endif
 67
 68struct qt2160_data {
 69	struct i2c_client *client;
 70	struct input_dev *input;
 71	struct delayed_work dwork;
 72	spinlock_t lock;        /* Protects canceling/rescheduling of dwork */
 73	unsigned short keycodes[ARRAY_SIZE(qt2160_key2code)];
 74	u16 key_matrix;
 75#ifdef CONFIG_LEDS_CLASS
 76	struct qt2160_led leds[QT2160_NUM_LEDS_X];
 77	struct mutex led_lock;
 78#endif
 79};
 80
 81static int qt2160_read(struct i2c_client *client, u8 reg);
 82static int qt2160_write(struct i2c_client *client, u8 reg, u8 data);
 83
 84#ifdef CONFIG_LEDS_CLASS
 85
 86static void qt2160_led_work(struct work_struct *work)
 87{
 88	struct qt2160_led *led = container_of(work, struct qt2160_led, work);
 89	struct qt2160_data *qt2160 = led->qt2160;
 90	struct i2c_client *client = qt2160->client;
 91	int value = led->new_brightness;
 92	u32 drive, pwmen;
 93
 94	mutex_lock(&qt2160->led_lock);
 95
 96	drive = qt2160_read(client, QT2160_CMD_DRIVE_X);
 97	pwmen = qt2160_read(client, QT2160_CMD_PWMEN_X);
 98	if (value != LED_OFF) {
 99		drive |= (1 << led->id);
100		pwmen |= (1 << led->id);
101
102	} else {
103		drive &= ~(1 << led->id);
104		pwmen &= ~(1 << led->id);
105	}
106	qt2160_write(client, QT2160_CMD_DRIVE_X, drive);
107	qt2160_write(client, QT2160_CMD_PWMEN_X, pwmen);
108
109	/*
110	 * Changing this register will change the brightness
111	 * of every LED in the qt2160. It's a HW limitation.
112	 */
113	if (value != LED_OFF)
114		qt2160_write(client, QT2160_CMD_PWM_DUTY, value);
115
116	mutex_unlock(&qt2160->led_lock);
117}
118
119static void qt2160_led_set(struct led_classdev *cdev,
120			   enum led_brightness value)
121{
122	struct qt2160_led *led = container_of(cdev, struct qt2160_led, cdev);
123
124	led->new_brightness = value;
125	schedule_work(&led->work);
126}
127
128#endif /* CONFIG_LEDS_CLASS */
129
130static int qt2160_read_block(struct i2c_client *client,
131			     u8 inireg, u8 *buffer, unsigned int count)
132{
133	int error, idx = 0;
134
135	/*
136	 * Can't use SMBus block data read. Check for I2C functionality to speed
137	 * things up whenever possible. Otherwise we will be forced to read
138	 * sequentially.
139	 */
140	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C))	{
141
142		error = i2c_smbus_write_byte(client, inireg + idx);
143		if (error) {
144			dev_err(&client->dev,
145				"couldn't send request. Returned %d\n", error);
146			return error;
147		}
148
149		error = i2c_master_recv(client, buffer, count);
150		if (error != count) {
151			dev_err(&client->dev,
152				"couldn't read registers. Returned %d bytes\n", error);
153			return error;
154		}
155	} else {
156
157		while (count--) {
158			int data;
159
160			error = i2c_smbus_write_byte(client, inireg + idx);
161			if (error) {
162				dev_err(&client->dev,
163					"couldn't send request. Returned %d\n", error);
164				return error;
165			}
166
167			data = i2c_smbus_read_byte(client);
168			if (data < 0) {
169				dev_err(&client->dev,
170					"couldn't read register. Returned %d\n", data);
171				return data;
172			}
173
174			buffer[idx++] = data;
175		}
176	}
177
178	return 0;
179}
180
181static int qt2160_get_key_matrix(struct qt2160_data *qt2160)
182{
183	struct i2c_client *client = qt2160->client;
184	struct input_dev *input = qt2160->input;
185	u8 regs[6];
186	u16 old_matrix, new_matrix;
187	int ret, i, mask;
188
189	dev_dbg(&client->dev, "requesting keys...\n");
190
191	/*
192	 * Read all registers from General Status Register
193	 * to GPIOs register
194	 */
195	ret = qt2160_read_block(client, QT2160_CMD_GSTAT, regs, 6);
196	if (ret) {
197		dev_err(&client->dev,
198			"could not perform chip read.\n");
199		return ret;
200	}
201
202	old_matrix = qt2160->key_matrix;
203	qt2160->key_matrix = new_matrix = (regs[2] << 8) | regs[1];
204
205	mask = 0x01;
206	for (i = 0; i < 16; ++i, mask <<= 1) {
207		int keyval = new_matrix & mask;
208
209		if ((old_matrix & mask) != keyval) {
210			input_report_key(input, qt2160->keycodes[i], keyval);
211			dev_dbg(&client->dev, "key %d %s\n",
212				i, keyval ? "pressed" : "released");
213		}
214	}
215
216	input_sync(input);
217
218	return 0;
219}
220
221static irqreturn_t qt2160_irq(int irq, void *_qt2160)
222{
223	struct qt2160_data *qt2160 = _qt2160;
224	unsigned long flags;
225
226	spin_lock_irqsave(&qt2160->lock, flags);
227
228	mod_delayed_work(system_wq, &qt2160->dwork, 0);
229
230	spin_unlock_irqrestore(&qt2160->lock, flags);
231
232	return IRQ_HANDLED;
233}
234
235static void qt2160_schedule_read(struct qt2160_data *qt2160)
236{
237	spin_lock_irq(&qt2160->lock);
238	schedule_delayed_work(&qt2160->dwork, QT2160_CYCLE_INTERVAL);
239	spin_unlock_irq(&qt2160->lock);
240}
241
242static void qt2160_worker(struct work_struct *work)
243{
244	struct qt2160_data *qt2160 =
245		container_of(work, struct qt2160_data, dwork.work);
246
247	dev_dbg(&qt2160->client->dev, "worker\n");
248
249	qt2160_get_key_matrix(qt2160);
250
251	/* Avoid device lock up by checking every so often */
252	qt2160_schedule_read(qt2160);
253}
254
255static int qt2160_read(struct i2c_client *client, u8 reg)
256{
257	int ret;
258
259	ret = i2c_smbus_write_byte(client, reg);
260	if (ret) {
261		dev_err(&client->dev,
262			"couldn't send request. Returned %d\n", ret);
263		return ret;
264	}
265
266	ret = i2c_smbus_read_byte(client);
267	if (ret < 0) {
268		dev_err(&client->dev,
269			"couldn't read register. Returned %d\n", ret);
270		return ret;
271	}
272
273	return ret;
274}
275
276static int qt2160_write(struct i2c_client *client, u8 reg, u8 data)
277{
278	int ret;
279
280	ret = i2c_smbus_write_byte_data(client, reg, data);
281	if (ret < 0)
282		dev_err(&client->dev,
283			"couldn't write data. Returned %d\n", ret);
284
285	return ret;
286}
287
288#ifdef CONFIG_LEDS_CLASS
289
290static int qt2160_register_leds(struct qt2160_data *qt2160)
291{
292	struct i2c_client *client = qt2160->client;
293	int ret;
294	int i;
295
296	mutex_init(&qt2160->led_lock);
297
298	for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
299		struct qt2160_led *led = &qt2160->leds[i];
300
301		snprintf(led->name, sizeof(led->name), "qt2160:x%d", i);
302		led->cdev.name = led->name;
303		led->cdev.brightness_set = qt2160_led_set;
304		led->cdev.brightness = LED_OFF;
305		led->id = i;
306		led->qt2160 = qt2160;
307
308		INIT_WORK(&led->work, qt2160_led_work);
309
310		ret = led_classdev_register(&client->dev, &led->cdev);
311		if (ret < 0)
312			return ret;
313	}
314
315	/* Tur off LEDs */
316	qt2160_write(client, QT2160_CMD_DRIVE_X, 0);
317	qt2160_write(client, QT2160_CMD_PWMEN_X, 0);
318	qt2160_write(client, QT2160_CMD_PWM_DUTY, 0);
319
320	return 0;
321}
322
323static void qt2160_unregister_leds(struct qt2160_data *qt2160)
324{
325	int i;
326
327	for (i = 0; i < QT2160_NUM_LEDS_X; i++) {
328		led_classdev_unregister(&qt2160->leds[i].cdev);
329		cancel_work_sync(&qt2160->leds[i].work);
330	}
331}
332
333#else
334
335static inline int qt2160_register_leds(struct qt2160_data *qt2160)
336{
337	return 0;
338}
339
340static inline void qt2160_unregister_leds(struct qt2160_data *qt2160)
341{
342}
343
344#endif
345
346static bool qt2160_identify(struct i2c_client *client)
347{
348	int id, ver, rev;
349
350	/* Read Chid ID to check if chip is valid */
351	id = qt2160_read(client, QT2160_CMD_CHIPID);
352	if (id != QT2160_VALID_CHIPID) {
353		dev_err(&client->dev, "ID %d not supported\n", id);
354		return false;
355	}
356
357	/* Read chip firmware version */
358	ver = qt2160_read(client, QT2160_CMD_CODEVER);
359	if (ver < 0) {
360		dev_err(&client->dev, "could not get firmware version\n");
361		return false;
362	}
363
364	/* Read chip firmware revision */
365	rev = qt2160_read(client, QT2160_CMD_SUBVER);
366	if (rev < 0) {
367		dev_err(&client->dev, "could not get firmware revision\n");
368		return false;
369	}
370
371	dev_info(&client->dev, "AT42QT2160 firmware version %d.%d.%d\n",
372			ver >> 4, ver & 0xf, rev);
373
374	return true;
375}
376
377static int qt2160_probe(struct i2c_client *client,
378			const struct i2c_device_id *id)
379{
380	struct qt2160_data *qt2160;
381	struct input_dev *input;
382	int i;
383	int error;
384
385	/* Check functionality */
386	error = i2c_check_functionality(client->adapter,
387			I2C_FUNC_SMBUS_BYTE);
388	if (!error) {
389		dev_err(&client->dev, "%s adapter not supported\n",
390				dev_driver_string(&client->adapter->dev));
391		return -ENODEV;
392	}
393
394	if (!qt2160_identify(client))
395		return -ENODEV;
396
397	/* Chip is valid and active. Allocate structure */
398	qt2160 = kzalloc(sizeof(struct qt2160_data), GFP_KERNEL);
399	input = input_allocate_device();
400	if (!qt2160 || !input) {
401		dev_err(&client->dev, "insufficient memory\n");
402		error = -ENOMEM;
403		goto err_free_mem;
404	}
405
406	qt2160->client = client;
407	qt2160->input = input;
408	INIT_DELAYED_WORK(&qt2160->dwork, qt2160_worker);
409	spin_lock_init(&qt2160->lock);
410
411	input->name = "AT42QT2160 Touch Sense Keyboard";
412	input->id.bustype = BUS_I2C;
413
414	input->keycode = qt2160->keycodes;
415	input->keycodesize = sizeof(qt2160->keycodes[0]);
416	input->keycodemax = ARRAY_SIZE(qt2160_key2code);
417
418	__set_bit(EV_KEY, input->evbit);
419	__clear_bit(EV_REP, input->evbit);
420	for (i = 0; i < ARRAY_SIZE(qt2160_key2code); i++) {
421		qt2160->keycodes[i] = qt2160_key2code[i];
422		__set_bit(qt2160_key2code[i], input->keybit);
423	}
424	__clear_bit(KEY_RESERVED, input->keybit);
425
426	/* Calibrate device */
427	error = qt2160_write(client, QT2160_CMD_CALIBRATE, 1);
428	if (error) {
429		dev_err(&client->dev, "failed to calibrate device\n");
430		goto err_free_mem;
431	}
432
433	if (client->irq) {
434		error = request_irq(client->irq, qt2160_irq,
435				    IRQF_TRIGGER_FALLING, "qt2160", qt2160);
436		if (error) {
437			dev_err(&client->dev,
438				"failed to allocate irq %d\n", client->irq);
439			goto err_free_mem;
440		}
441	}
442
443	error = qt2160_register_leds(qt2160);
444	if (error) {
445		dev_err(&client->dev, "Failed to register leds\n");
446		goto err_free_irq;
447	}
448
449	error = input_register_device(qt2160->input);
450	if (error) {
451		dev_err(&client->dev,
452			"Failed to register input device\n");
453		goto err_unregister_leds;
454	}
455
456	i2c_set_clientdata(client, qt2160);
457	qt2160_schedule_read(qt2160);
458
459	return 0;
460
461err_unregister_leds:
462	qt2160_unregister_leds(qt2160);
463err_free_irq:
464	if (client->irq)
465		free_irq(client->irq, qt2160);
466err_free_mem:
467	input_free_device(input);
468	kfree(qt2160);
469	return error;
470}
471
472static int qt2160_remove(struct i2c_client *client)
473{
474	struct qt2160_data *qt2160 = i2c_get_clientdata(client);
475
476	qt2160_unregister_leds(qt2160);
477
478	/* Release IRQ so no queue will be scheduled */
479	if (client->irq)
480		free_irq(client->irq, qt2160);
481
482	cancel_delayed_work_sync(&qt2160->dwork);
483
484	input_unregister_device(qt2160->input);
485	kfree(qt2160);
486
487	return 0;
488}
489
490static const struct i2c_device_id qt2160_idtable[] = {
491	{ "qt2160", 0, },
492	{ }
493};
494
495MODULE_DEVICE_TABLE(i2c, qt2160_idtable);
496
497static struct i2c_driver qt2160_driver = {
498	.driver = {
499		.name	= "qt2160",
 
500	},
501
502	.id_table	= qt2160_idtable,
503	.probe		= qt2160_probe,
504	.remove		= qt2160_remove,
505};
506
507module_i2c_driver(qt2160_driver);
508
509MODULE_AUTHOR("Raphael Derosso Pereira <raphaelpereira@gmail.com>");
510MODULE_DESCRIPTION("Driver for AT42QT2160 Touch Sensor");
511MODULE_LICENSE("GPL");