2 * Synaptics touchpad with I2C interface
4 * Copyright (C) 2009 Compulab, Ltd.
5 * Mike Rapoport <mike@compulab.co.il>
6 * Igor Grinberg <grinberg@compulab.co.il>
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file COPYING in the main directory of this archive for
13 #include <linux/module.h>
14 #include <linux/i2c.h>
15 #include <linux/irq.h>
16 #include <linux/interrupt.h>
17 #include <linux/input.h>
18 #include <linux/delay.h>
19 #include <linux/workqueue.h>
20 #include <linux/slab.h>
23 #define DRIVER_NAME "synaptics_i2c"
24 /* maximum product id is 15 characters */
25 #define PRODUCT_ID_LENGTH 15
26 #define REGISTER_LENGTH 8
29 * after soft reset, we should wait for 1 ms
30 * before the device becomes operational
32 #define SOFT_RESET_DELAY_MS 3
33 /* and after hard reset, we should wait for max 500ms */
34 #define HARD_RESET_DELAY_MS 500
36 /* Registers by SMBus address */
37 #define PAGE_SEL_REG 0xff
38 #define DEVICE_STATUS_REG 0x09
40 /* Registers by RMI address */
41 #define DEV_CONTROL_REG 0x0000
42 #define INTERRUPT_EN_REG 0x0001
43 #define ERR_STAT_REG 0x0002
44 #define INT_REQ_STAT_REG 0x0003
45 #define DEV_COMMAND_REG 0x0004
47 #define RMI_PROT_VER_REG 0x0200
48 #define MANUFACT_ID_REG 0x0201
49 #define PHYS_INT_VER_REG 0x0202
50 #define PROD_PROPERTY_REG 0x0203
51 #define INFO_QUERY_REG0 0x0204
52 #define INFO_QUERY_REG1 (INFO_QUERY_REG0 + 1)
53 #define INFO_QUERY_REG2 (INFO_QUERY_REG0 + 2)
54 #define INFO_QUERY_REG3 (INFO_QUERY_REG0 + 3)
56 #define PRODUCT_ID_REG0 0x0210
57 #define PRODUCT_ID_REG1 (PRODUCT_ID_REG0 + 1)
58 #define PRODUCT_ID_REG2 (PRODUCT_ID_REG0 + 2)
59 #define PRODUCT_ID_REG3 (PRODUCT_ID_REG0 + 3)
60 #define PRODUCT_ID_REG4 (PRODUCT_ID_REG0 + 4)
61 #define PRODUCT_ID_REG5 (PRODUCT_ID_REG0 + 5)
62 #define PRODUCT_ID_REG6 (PRODUCT_ID_REG0 + 6)
63 #define PRODUCT_ID_REG7 (PRODUCT_ID_REG0 + 7)
64 #define PRODUCT_ID_REG8 (PRODUCT_ID_REG0 + 8)
65 #define PRODUCT_ID_REG9 (PRODUCT_ID_REG0 + 9)
66 #define PRODUCT_ID_REG10 (PRODUCT_ID_REG0 + 10)
67 #define PRODUCT_ID_REG11 (PRODUCT_ID_REG0 + 11)
68 #define PRODUCT_ID_REG12 (PRODUCT_ID_REG0 + 12)
69 #define PRODUCT_ID_REG13 (PRODUCT_ID_REG0 + 13)
70 #define PRODUCT_ID_REG14 (PRODUCT_ID_REG0 + 14)
71 #define PRODUCT_ID_REG15 (PRODUCT_ID_REG0 + 15)
73 #define DATA_REG0 0x0400
74 #define ABS_PRESSURE_REG 0x0401
75 #define ABS_MSB_X_REG 0x0402
76 #define ABS_LSB_X_REG (ABS_MSB_X_REG + 1)
77 #define ABS_MSB_Y_REG 0x0404
78 #define ABS_LSB_Y_REG (ABS_MSB_Y_REG + 1)
79 #define REL_X_REG 0x0406
80 #define REL_Y_REG 0x0407
82 #define DEV_QUERY_REG0 0x1000
83 #define DEV_QUERY_REG1 (DEV_QUERY_REG0 + 1)
84 #define DEV_QUERY_REG2 (DEV_QUERY_REG0 + 2)
85 #define DEV_QUERY_REG3 (DEV_QUERY_REG0 + 3)
86 #define DEV_QUERY_REG4 (DEV_QUERY_REG0 + 4)
87 #define DEV_QUERY_REG5 (DEV_QUERY_REG0 + 5)
88 #define DEV_QUERY_REG6 (DEV_QUERY_REG0 + 6)
89 #define DEV_QUERY_REG7 (DEV_QUERY_REG0 + 7)
90 #define DEV_QUERY_REG8 (DEV_QUERY_REG0 + 8)
92 #define GENERAL_2D_CONTROL_REG 0x1041
93 #define SENSOR_SENSITIVITY_REG 0x1044
94 #define SENS_MAX_POS_MSB_REG 0x1046
95 #define SENS_MAX_POS_LSB_REG (SENS_MAX_POS_UPPER_REG + 1)
98 /* Device Control Register Bits */
99 #define REPORT_RATE_1ST_BIT 6
101 /* Interrupt Enable Register Bits (INTERRUPT_EN_REG) */
102 #define F10_ABS_INT_ENA 0
103 #define F10_REL_INT_ENA 1
104 #define F20_INT_ENA 2
106 /* Interrupt Request Register Bits (INT_REQ_STAT_REG | DEVICE_STATUS_REG) */
107 #define F10_ABS_INT_REQ 0
108 #define F10_REL_INT_REQ 1
109 #define F20_INT_REQ 2
110 /* Device Status Register Bits (DEVICE_STATUS_REG) */
111 #define STAT_CONFIGURED 6
114 /* Device Command Register Bits (DEV_COMMAND_REG) */
115 #define RESET_COMMAND 0x01
116 #define REZERO_COMMAND 0x02
118 /* Data Register 0 Bits (DATA_REG0) */
121 /* Device Query Registers Bits */
123 #define HAS_PALM_DETECT 1
124 #define HAS_MULTI_FING 2
125 #define HAS_SCROLLER 4
126 #define HAS_2D_SCROLL 5
128 /* General 2D Control Register Bits (GENERAL_2D_CONTROL_REG) */
129 #define NO_DECELERATION 1
130 #define REDUCE_REPORTING 3
134 /* Device Control Register Masks (DEV_CONTROL_REG) */
135 #define REPORT_RATE_MSK 0xc0
136 #define SLEEP_MODE_MSK 0x07
138 /* Device Sleep Modes */
139 #define FULL_AWAKE 0x0
140 #define NORMAL_OP 0x1
141 #define LOW_PWR_OP 0x2
142 #define VERY_LOW_PWR_OP 0x3
143 #define SENS_SLEEP 0x4
144 #define SLEEP_MOD 0x5
145 #define DEEP_SLEEP 0x6
146 #define HIBERNATE 0x7
148 /* Interrupt Register Mask */
149 /* (INT_REQ_STAT_REG | DEVICE_STATUS_REG | INTERRUPT_EN_REG) */
150 #define INT_ENA_REQ_MSK 0x07
151 #define INT_ENA_ABS_MSK 0x01
152 #define INT_ENA_REL_MSK 0x02
153 #define INT_ENA_F20_MSK 0x04
155 /* Device Status Register Masks (DEVICE_STATUS_REG) */
156 #define CONFIGURED_MSK 0x40
157 #define ERROR_MSK 0x80
159 /* Data Register 0 Masks */
160 #define FINGER_WIDTH_MSK 0xf0
161 #define GESTURE_MSK 0x08
162 #define SENSOR_STATUS_MSK 0x07
165 * MSB Position Register Masks
166 * ABS_MSB_X_REG | ABS_MSB_Y_REG | SENS_MAX_POS_MSB_REG |
167 * DEV_QUERY_REG3 | DEV_QUERY_REG5
169 #define MSB_POSITION_MSK 0x1f
171 /* Device Query Registers Masks */
174 #define NUM_EXTRA_POS_MSK 0x07
176 /* When in IRQ mode read the device every THREAD_IRQ_SLEEP_SECS */
177 #define THREAD_IRQ_SLEEP_SECS 2
178 #define THREAD_IRQ_SLEEP_MSECS (THREAD_IRQ_SLEEP_SECS * MSEC_PER_SEC)
181 * When in Polling mode and no data received for NO_DATA_THRES msecs
182 * reduce the polling rate to NO_DATA_SLEEP_MSECS
184 #define NO_DATA_THRES (MSEC_PER_SEC)
185 #define NO_DATA_SLEEP_MSECS (MSEC_PER_SEC / 4)
187 /* Control touchpad's No Deceleration option */
188 static bool no_decel
= 1;
189 module_param(no_decel
, bool, 0644);
190 MODULE_PARM_DESC(no_decel
, "No Deceleration. Default = 1 (on)");
192 /* Control touchpad's Reduced Reporting option */
193 static bool reduce_report
;
194 module_param(reduce_report
, bool, 0644);
195 MODULE_PARM_DESC(reduce_report
, "Reduced Reporting. Default = 0 (off)");
197 /* Control touchpad's No Filter option */
198 static bool no_filter
;
199 module_param(no_filter
, bool, 0644);
200 MODULE_PARM_DESC(no_filter
, "No Filter. Default = 0 (off)");
203 * touchpad Attention line is Active Low and Open Drain,
204 * therefore should be connected to pulled up line
205 * and the irq configuration should be set to Falling Edge Trigger
207 /* Control IRQ / Polling option */
208 static bool polling_req
;
209 module_param(polling_req
, bool, 0444);
210 MODULE_PARM_DESC(polling_req
, "Request Polling. Default = 0 (use irq)");
212 /* Control Polling Rate */
213 static int scan_rate
= 80;
214 module_param(scan_rate
, int, 0644);
215 MODULE_PARM_DESC(scan_rate
, "Polling rate in times/sec. Default = 80");
217 /* The main device structure */
218 struct synaptics_i2c
{
219 struct i2c_client
*client
;
220 struct input_dev
*input
;
221 struct delayed_work dwork
;
225 int reduce_report_param
;
231 static inline void set_scan_rate(struct synaptics_i2c
*touch
, int scan_rate
)
233 touch
->scan_ms
= MSEC_PER_SEC
/ scan_rate
;
234 touch
->scan_rate_param
= scan_rate
;
238 * Driver's initial design makes no race condition possible on i2c bus,
239 * so there is no need in any locking.
240 * Keep it in mind, while playing with the code.
242 static s32
synaptics_i2c_reg_get(struct i2c_client
*client
, u16 reg
)
246 ret
= i2c_smbus_write_byte_data(client
, PAGE_SEL_REG
, reg
>> 8);
248 ret
= i2c_smbus_read_byte_data(client
, reg
& 0xff);
253 static s32
synaptics_i2c_reg_set(struct i2c_client
*client
, u16 reg
, u8 val
)
257 ret
= i2c_smbus_write_byte_data(client
, PAGE_SEL_REG
, reg
>> 8);
259 ret
= i2c_smbus_write_byte_data(client
, reg
& 0xff, val
);
264 static s32
synaptics_i2c_word_get(struct i2c_client
*client
, u16 reg
)
268 ret
= i2c_smbus_write_byte_data(client
, PAGE_SEL_REG
, reg
>> 8);
270 ret
= i2c_smbus_read_word_data(client
, reg
& 0xff);
275 static int synaptics_i2c_config(struct i2c_client
*client
)
280 /* set Report Rate to Device Highest (>=80) and Sleep to normal */
281 ret
= synaptics_i2c_reg_set(client
, DEV_CONTROL_REG
, 0xc1);
285 /* set Interrupt Disable to Func20 / Enable to Func10) */
286 int_en
= (polling_req
) ? 0 : INT_ENA_ABS_MSK
| INT_ENA_REL_MSK
;
287 ret
= synaptics_i2c_reg_set(client
, INTERRUPT_EN_REG
, int_en
);
291 control
= synaptics_i2c_reg_get(client
, GENERAL_2D_CONTROL_REG
);
292 /* No Deceleration */
293 control
|= no_decel
? 1 << NO_DECELERATION
: 0;
294 /* Reduced Reporting */
295 control
|= reduce_report
? 1 << REDUCE_REPORTING
: 0;
297 control
|= no_filter
? 1 << NO_FILTER
: 0;
298 ret
= synaptics_i2c_reg_set(client
, GENERAL_2D_CONTROL_REG
, control
);
305 static int synaptics_i2c_reset_config(struct i2c_client
*client
)
309 /* Reset the Touchpad */
310 ret
= synaptics_i2c_reg_set(client
, DEV_COMMAND_REG
, RESET_COMMAND
);
312 dev_err(&client
->dev
, "Unable to reset device\n");
314 msleep(SOFT_RESET_DELAY_MS
);
315 ret
= synaptics_i2c_config(client
);
317 dev_err(&client
->dev
, "Unable to config device\n");
323 static int synaptics_i2c_check_error(struct i2c_client
*client
)
327 status
= i2c_smbus_read_byte_data(client
, DEVICE_STATUS_REG
) &
328 (CONFIGURED_MSK
| ERROR_MSK
);
330 if (status
!= CONFIGURED_MSK
)
331 ret
= synaptics_i2c_reset_config(client
);
336 static bool synaptics_i2c_get_input(struct synaptics_i2c
*touch
)
338 struct input_dev
*input
= touch
->input
;
339 int xy_delta
, gesture
;
343 /* Deal with spontanious resets and errors */
344 if (synaptics_i2c_check_error(touch
->client
))
347 /* Get Gesture Bit */
348 data
= synaptics_i2c_reg_get(touch
->client
, DATA_REG0
);
349 gesture
= (data
>> GESTURE
) & 0x1;
352 * Get Relative axes. we have to get them in one shot,
353 * so we get 2 bytes starting from REL_X_REG.
355 xy_delta
= synaptics_i2c_word_get(touch
->client
, REL_X_REG
) & 0xffff;
357 /* Separate X from Y */
358 x_delta
= xy_delta
& 0xff;
359 y_delta
= (xy_delta
>> REGISTER_LENGTH
) & 0xff;
361 /* Report the button event */
362 input_report_key(input
, BTN_LEFT
, gesture
);
364 /* Report the deltas */
365 input_report_rel(input
, REL_X
, x_delta
);
366 input_report_rel(input
, REL_Y
, -y_delta
);
369 return xy_delta
|| gesture
;
372 static void synaptics_i2c_reschedule_work(struct synaptics_i2c
*touch
,
377 spin_lock_irqsave(&touch
->lock
, flags
);
379 mod_delayed_work(system_wq
, &touch
->dwork
, delay
);
381 spin_unlock_irqrestore(&touch
->lock
, flags
);
384 static irqreturn_t
synaptics_i2c_irq(int irq
, void *dev_id
)
386 struct synaptics_i2c
*touch
= dev_id
;
388 synaptics_i2c_reschedule_work(touch
, 0);
393 static void synaptics_i2c_check_params(struct synaptics_i2c
*touch
)
397 if (scan_rate
!= touch
->scan_rate_param
)
398 set_scan_rate(touch
, scan_rate
);
400 if (no_decel
!= touch
->no_decel_param
) {
401 touch
->no_decel_param
= no_decel
;
405 if (no_filter
!= touch
->no_filter_param
) {
406 touch
->no_filter_param
= no_filter
;
410 if (reduce_report
!= touch
->reduce_report_param
) {
411 touch
->reduce_report_param
= reduce_report
;
416 synaptics_i2c_reset_config(touch
->client
);
419 /* Control the Device polling rate / Work Handler sleep time */
420 static unsigned long synaptics_i2c_adjust_delay(struct synaptics_i2c
*touch
,
423 unsigned long delay
, nodata_count_thres
;
426 delay
= touch
->scan_ms
;
428 touch
->no_data_count
= 0;
430 nodata_count_thres
= NO_DATA_THRES
/ touch
->scan_ms
;
431 if (touch
->no_data_count
< nodata_count_thres
)
432 touch
->no_data_count
++;
434 delay
= NO_DATA_SLEEP_MSECS
;
436 return msecs_to_jiffies(delay
);
438 delay
= msecs_to_jiffies(THREAD_IRQ_SLEEP_MSECS
);
439 return round_jiffies_relative(delay
);
444 static void synaptics_i2c_work_handler(struct work_struct
*work
)
447 struct synaptics_i2c
*touch
=
448 container_of(work
, struct synaptics_i2c
, dwork
.work
);
451 synaptics_i2c_check_params(touch
);
453 have_data
= synaptics_i2c_get_input(touch
);
454 delay
= synaptics_i2c_adjust_delay(touch
, have_data
);
457 * While interrupt driven, there is no real need to poll the device.
458 * But touchpads are very sensitive, so there could be errors
459 * related to physical environment and the attention line isn't
460 * necessarily asserted. In such case we can lose the touchpad.
461 * We poll the device once in THREAD_IRQ_SLEEP_SECS and
462 * if error is detected, we try to reset and reconfigure the touchpad.
464 synaptics_i2c_reschedule_work(touch
, delay
);
467 static int synaptics_i2c_open(struct input_dev
*input
)
469 struct synaptics_i2c
*touch
= input_get_drvdata(input
);
472 ret
= synaptics_i2c_reset_config(touch
->client
);
477 synaptics_i2c_reschedule_work(touch
,
478 msecs_to_jiffies(NO_DATA_SLEEP_MSECS
));
483 static void synaptics_i2c_close(struct input_dev
*input
)
485 struct synaptics_i2c
*touch
= input_get_drvdata(input
);
488 synaptics_i2c_reg_set(touch
->client
, INTERRUPT_EN_REG
, 0);
490 cancel_delayed_work_sync(&touch
->dwork
);
492 /* Save some power */
493 synaptics_i2c_reg_set(touch
->client
, DEV_CONTROL_REG
, DEEP_SLEEP
);
496 static void synaptics_i2c_set_input_params(struct synaptics_i2c
*touch
)
498 struct input_dev
*input
= touch
->input
;
500 input
->name
= touch
->client
->name
;
501 input
->phys
= touch
->client
->adapter
->name
;
502 input
->id
.bustype
= BUS_I2C
;
503 input
->id
.version
= synaptics_i2c_word_get(touch
->client
,
505 input
->dev
.parent
= &touch
->client
->dev
;
506 input
->open
= synaptics_i2c_open
;
507 input
->close
= synaptics_i2c_close
;
508 input_set_drvdata(input
, touch
);
510 /* Register the device as mouse */
511 __set_bit(EV_REL
, input
->evbit
);
512 __set_bit(REL_X
, input
->relbit
);
513 __set_bit(REL_Y
, input
->relbit
);
515 /* Register device's buttons and keys */
516 __set_bit(EV_KEY
, input
->evbit
);
517 __set_bit(BTN_LEFT
, input
->keybit
);
520 static struct synaptics_i2c
*synaptics_i2c_touch_create(struct i2c_client
*client
)
522 struct synaptics_i2c
*touch
;
524 touch
= kzalloc(sizeof(struct synaptics_i2c
), GFP_KERNEL
);
528 touch
->client
= client
;
529 touch
->no_decel_param
= no_decel
;
530 touch
->scan_rate_param
= scan_rate
;
531 set_scan_rate(touch
, scan_rate
);
532 INIT_DELAYED_WORK(&touch
->dwork
, synaptics_i2c_work_handler
);
533 spin_lock_init(&touch
->lock
);
538 static int synaptics_i2c_probe(struct i2c_client
*client
,
539 const struct i2c_device_id
*dev_id
)
542 struct synaptics_i2c
*touch
;
544 touch
= synaptics_i2c_touch_create(client
);
548 ret
= synaptics_i2c_reset_config(client
);
555 touch
->input
= input_allocate_device();
561 synaptics_i2c_set_input_params(touch
);
564 dev_dbg(&touch
->client
->dev
,
565 "Requesting IRQ: %d\n", touch
->client
->irq
);
567 ret
= request_irq(touch
->client
->irq
, synaptics_i2c_irq
,
568 IRQ_TYPE_EDGE_FALLING
,
571 dev_warn(&touch
->client
->dev
,
572 "IRQ request failed: %d, "
573 "falling back to polling\n", ret
);
575 synaptics_i2c_reg_set(touch
->client
,
576 INTERRUPT_EN_REG
, 0);
581 dev_dbg(&touch
->client
->dev
,
582 "Using polling at rate: %d times/sec\n", scan_rate
);
584 /* Register the device in input subsystem */
585 ret
= input_register_device(touch
->input
);
587 dev_err(&client
->dev
,
588 "Input device register failed: %d\n", ret
);
592 i2c_set_clientdata(client
, touch
);
597 input_free_device(touch
->input
);
604 static int synaptics_i2c_remove(struct i2c_client
*client
)
606 struct synaptics_i2c
*touch
= i2c_get_clientdata(client
);
609 free_irq(client
->irq
, touch
);
611 input_unregister_device(touch
->input
);
617 #ifdef CONFIG_PM_SLEEP
618 static int synaptics_i2c_suspend(struct device
*dev
)
620 struct i2c_client
*client
= to_i2c_client(dev
);
621 struct synaptics_i2c
*touch
= i2c_get_clientdata(client
);
623 cancel_delayed_work_sync(&touch
->dwork
);
625 /* Save some power */
626 synaptics_i2c_reg_set(touch
->client
, DEV_CONTROL_REG
, DEEP_SLEEP
);
631 static int synaptics_i2c_resume(struct device
*dev
)
634 struct i2c_client
*client
= to_i2c_client(dev
);
635 struct synaptics_i2c
*touch
= i2c_get_clientdata(client
);
637 ret
= synaptics_i2c_reset_config(client
);
641 synaptics_i2c_reschedule_work(touch
,
642 msecs_to_jiffies(NO_DATA_SLEEP_MSECS
));
648 static SIMPLE_DEV_PM_OPS(synaptics_i2c_pm
, synaptics_i2c_suspend
,
649 synaptics_i2c_resume
);
651 static const struct i2c_device_id synaptics_i2c_id_table
[] = {
652 { "synaptics_i2c", 0 },
655 MODULE_DEVICE_TABLE(i2c
, synaptics_i2c_id_table
);
657 static struct i2c_driver synaptics_i2c_driver
= {
660 .owner
= THIS_MODULE
,
661 .pm
= &synaptics_i2c_pm
,
664 .probe
= synaptics_i2c_probe
,
665 .remove
= synaptics_i2c_remove
,
667 .id_table
= synaptics_i2c_id_table
,
670 module_i2c_driver(synaptics_i2c_driver
);
672 MODULE_DESCRIPTION("Synaptics I2C touchpad driver");
673 MODULE_AUTHOR("Mike Rapoport, Igor Grinberg, Compulab");
674 MODULE_LICENSE("GPL");