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clearpad_tm1217.c
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1 /*
2  * clearpad_tm1217.c - Touch Screen driver for Synaptics Clearpad
3  * TM1217 controller
4  *
5  * Copyright (C) 2008 Intel Corp
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; version 2 of the License.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License along
19  * with this program; ifnot, write to the Free Software Foundation, Inc.,
20  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21  *
22  * Questions/Comments/Bug fixes to Ramesh Agarwal ([email protected])
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25 
26 #include <linux/module.h>
27 #include <linux/kernel.h>
28 #include <linux/input.h>
29 #include <linux/interrupt.h>
30 #include <linux/io.h>
31 #include <linux/i2c.h>
32 #include <linux/timer.h>
33 #include <linux/gpio.h>
34 #include <linux/hrtimer.h>
35 #include <linux/kthread.h>
36 #include <linux/delay.h>
37 #include <linux/slab.h>
38 #include "cp_tm1217.h"
39 
40 #define CPTM1217_DEVICE_NAME "cptm1217"
41 #define CPTM1217_DRIVER_NAME CPTM1217_DEVICE_NAME
42 
43 #define MAX_TOUCH_SUPPORTED 2
44 #define TOUCH_SUPPORTED 1
45 #define SAMPLING_FREQ 80 /* Frequency in HZ */
46 #define DELAY_BTWIN_SAMPLE (1000 / SAMPLING_FREQ)
47 #define WAIT_FOR_RESPONSE 5 /* 5msec just works */
48 #define MAX_RETRIES 5 /* As above */
49 #define INCREMENTAL_DELAY 5 /* As above */
50 
51 /* Regster Definitions */
52 #define TMA1217_DEV_STATUS 0x13 /* Device Status */
53 #define TMA1217_INT_STATUS 0x14 /* Interrupt Status */
54 
55 /* Controller can detect up to 2 possible finger touches.
56  * Each finger touch provides 12 bit X Y co-ordinates, the values are split
57  * across 2 registers, and an 8 bit Z value */
58 #define TMA1217_FINGER_STATE 0x18 /* Finger State */
59 #define TMA1217_FINGER1_X_HIGHER8 0x19 /* Higher 8 bit of X coordinate */
60 #define TMA1217_FINGER1_Y_HIGHER8 0x1A /* Higher 8 bit of Y coordinate */
61 #define TMA1217_FINGER1_XY_LOWER4 0x1B /* Lower 4 bits of X and Y */
62 #define TMA1217_FINGER1_Z_VALUE 0x1D /* 8 bit Z value for finger 1 */
63 #define TMA1217_FINGER2_X_HIGHER8 0x1E /* Higher 8 bit of X coordinate */
64 #define TMA1217_FINGER2_Y_HIGHER8 0x1F /* Higher 8 bit of Y coordinate */
65 #define TMA1217_FINGER2_XY_LOWER4 0x20 /* Lower 4 bits of X and Y */
66 #define TMA1217_FINGER2_Z_VALUE 0x22 /* 8 bit Z value for finger 2 */
67 #define TMA1217_DEVICE_CTRL 0x23 /* Device Control */
68 #define TMA1217_INTERRUPT_ENABLE 0x24 /* Interrupt Enable */
69 #define TMA1217_REPORT_MODE 0x2B /* Reporting Mode */
70 #define TMA1217_MAX_X_LOWER8 0x31 /* Bit 0-7 for Max X */
71 #define TMA1217_MAX_X_HIGHER4 0x32 /* Bit 8-11 for Max X */
72 #define TMA1217_MAX_Y_LOWER8 0x33 /* Bit 0-7 for Max Y */
73 #define TMA1217_MAX_Y_HIGHER4 0x34 /* Bit 8-11 for Max Y */
74 #define TMA1217_DEVICE_CMD_RESET 0x67 /* Device CMD reg for reset */
75 #define TMA1217_DEVICE_CMD_REZERO 0x69 /* Device CMD reg for rezero */
76 
77 #define TMA1217_MANUFACTURER_ID 0x73 /* Manufacturer Id */
78 #define TMA1217_PRODUCT_FAMILY 0x75 /* Product Family */
79 #define TMA1217_FIRMWARE_REVISION 0x76 /* Firmware Revision */
80 #define TMA1217_SERIAL_NO_HIGH 0x7C /* Bit 8-15 of device serial no. */
81 #define TMA1217_SERIAL_NO_LOW 0x7D /* Bit 0-7 of device serial no. */
82 #define TMA1217_PRODUCT_ID_START 0x7E /* Start address for 10 byte ID */
83 #define TMA1217_DEVICE_CAPABILITY 0x8B /* Reporting capability */
84 
85 
86 /*
87  * The touch position structure.
88  */
89 struct touch_state {
90  int x;
91  int y;
92  bool button;
93 };
94 
95 /* Device Specific info given by the controller */
96 struct cp_dev_info {
99 };
100 
101 /* Vendor related info given by the controller */
107 };
108 
109 /*
110  * Private structure to store the device details
111  */
114  struct device *dev;
117  struct input_dev_info {
118  char phys[32];
119  char name[128];
120  struct input_dev *input;
123 
126 
127  int gpio;
128 };
129 
130 
131 /* The following functions are used to read/write registers on the device
132  * as per the RMI prorocol. Technically, a page select should be written
133  * before doing read/write but since the register offsets are below 0xFF
134  * we can use the default value of page which is 0x00
135  */
136 static int cp_tm1217_read(struct cp_tm1217_device *ts,
137  u8 *req, int size)
138 {
139  int i, retval;
140 
141  /* Send the address */
142  retval = i2c_master_send(ts->client, &req[0], 1);
143  if (retval != 1) {
144  dev_err(ts->dev, "cp_tm1217: I2C send failed\n");
145  return retval;
146  }
148  for (i = 0; i < MAX_RETRIES; i++) {
149  retval = i2c_master_recv(ts->client, &req[1], size);
150  if (retval == size) {
151  break;
152  } else {
154  dev_dbg(ts->dev, "cp_tm1217: Retry count is %d\n", i);
155  }
156  }
157  if (retval != size)
158  dev_err(ts->dev, "cp_tm1217: Read from device failed\n");
159 
160  return retval;
161 }
162 
163 static int cp_tm1217_write(struct cp_tm1217_device *ts,
164  u8 *req, int size)
165 {
166  int retval;
167 
168  /* Send the address and the data to be written */
169  retval = i2c_master_send(ts->client, &req[0], size + 1);
170  if (retval != size + 1) {
171  dev_err(ts->dev, "cp_tm1217: I2C write failed: %d\n", retval);
172  return retval;
173  }
174  /* Wait for the write to complete. TBD why this is required */
176 
177  return size;
178 }
179 
180 static int cp_tm1217_mask_interrupt(struct cp_tm1217_device *ts)
181 {
182  u8 req[2];
183  int retval;
184 
185  req[0] = TMA1217_INTERRUPT_ENABLE;
186  req[1] = 0x0;
187  retval = cp_tm1217_write(ts, req, 1);
188  if (retval != 1)
189  return -EIO;
190 
191  return 0;
192 }
193 
194 static int cp_tm1217_unmask_interrupt(struct cp_tm1217_device *ts)
195 {
196  u8 req[2];
197  int retval;
198 
199  req[0] = TMA1217_INTERRUPT_ENABLE;
200  req[1] = 0xa;
201  retval = cp_tm1217_write(ts, req, 1);
202  if (retval != 1)
203  return -EIO;
204 
205  return 0;
206 }
207 
208 static void process_touch(struct cp_tm1217_device *ts, int index)
209 {
210  int retval;
211  struct input_dev_info *input_info =
212  (struct input_dev_info *)&ts->cp_input_info[index];
213  u8 xy_data[6];
214 
215  if (index == 0)
216  xy_data[0] = TMA1217_FINGER1_X_HIGHER8;
217  else
218  xy_data[0] = TMA1217_FINGER2_X_HIGHER8;
219 
220  retval = cp_tm1217_read(ts, xy_data, 5);
221  if (retval < 5) {
222  dev_err(ts->dev, "cp_tm1217: XY read from device failed\n");
223  return;
224  }
225 
226  /* Note: Currently not using the Z values but may be requried in
227  the future. */
228  input_info->touch.x = (xy_data[1] << 4)
229  | (xy_data[3] & 0x0F);
230  input_info->touch.y = (xy_data[2] << 4)
231  | ((xy_data[3] & 0xF0) >> 4);
232  input_report_abs(input_info->input, ABS_X, input_info->touch.x);
233  input_report_abs(input_info->input, ABS_Y, input_info->touch.y);
234  input_sync(input_info->input);
235 }
236 
237 static void cp_tm1217_get_data(struct cp_tm1217_device *ts)
238 {
239  u8 req[2];
240  int retval, i, finger_touched = 0;
241 
242  do {
243  req[0] = TMA1217_FINGER_STATE;
244  retval = cp_tm1217_read(ts, req, 1);
245  if (retval != 1) {
246  dev_err(ts->dev,
247  "cp_tm1217: Read from device failed\n");
248  continue;
249  }
250  finger_touched = 0;
251  /* Start sampling until the pressure is below
252  threshold */
253  for (i = 0; i < TOUCH_SUPPORTED; i++) {
254  if (req[1] & 0x3) {
255  finger_touched++;
256  if (ts->cp_input_info[i].touch.button == 0) {
257  /* send the button touch event */
258  input_report_key(
259  ts->cp_input_info[i].input,
260  BTN_TOUCH, 1);
261  ts->cp_input_info[i].touch.button = 1;
262  }
263  process_touch(ts, i);
264  } else {
265  if (ts->cp_input_info[i].touch.button == 1) {
266  /* send the button release event */
267  input_report_key(
268  ts->cp_input_info[i].input,
269  BTN_TOUCH, 0);
270  input_sync(ts->cp_input_info[i].input);
271  ts->cp_input_info[i].touch.button = 0;
272  }
273  }
274  req[1] = req[1] >> 2;
275  }
277  } while (finger_touched > 0);
278 }
279 
280 static irqreturn_t cp_tm1217_sample_thread(int irq, void *handle)
281 {
282  struct cp_tm1217_device *ts = (struct cp_tm1217_device *) handle;
283  u8 req[2];
284  int retval;
285 
286  /* Chedk if another thread is already running */
287  mutex_lock(&ts->thread_mutex);
288  if (ts->thread_running == 1) {
290  return IRQ_HANDLED;
291  } else {
292  ts->thread_running = 1;
294  }
295 
296  /* Mask the interrupts */
297  retval = cp_tm1217_mask_interrupt(ts);
298 
299  /* Read the Interrupt Status register to find the cause of the
300  Interrupt */
301  req[0] = TMA1217_INT_STATUS;
302  retval = cp_tm1217_read(ts, req, 1);
303  if (retval != 1)
304  goto exit_thread;
305 
306  if (!(req[1] & 0x8))
307  goto exit_thread;
308 
309  cp_tm1217_get_data(ts);
310 
312  /* Unmask the interrupts before going to sleep */
313  retval = cp_tm1217_unmask_interrupt(ts);
314 
315  mutex_lock(&ts->thread_mutex);
316  ts->thread_running = 0;
318 
319  return IRQ_HANDLED;
320 }
321 
322 static int cp_tm1217_init_data(struct cp_tm1217_device *ts)
323 {
324  int retval;
325  u8 req[2];
326 
327  /* Read the vendor id/ fw revision etc. Ignoring return check as this
328  is non critical info */
329  req[0] = TMA1217_MANUFACTURER_ID;
330  retval = cp_tm1217_read(ts, req, 1);
331  ts->vinfo.vendor_id = req[1];
332 
333  req[0] = TMA1217_PRODUCT_FAMILY;
334  retval = cp_tm1217_read(ts, req, 1);
335  ts->vinfo.product_family = req[1];
336 
337  req[0] = TMA1217_FIRMWARE_REVISION;
338  retval = cp_tm1217_read(ts, req, 1);
339  ts->vinfo.firmware_rev = req[1];
340 
341  req[0] = TMA1217_SERIAL_NO_HIGH;
342  retval = cp_tm1217_read(ts, req, 1);
343  ts->vinfo.serial_no = (req[1] << 8);
344 
345  req[0] = TMA1217_SERIAL_NO_LOW;
346  retval = cp_tm1217_read(ts, req, 1);
347  ts->vinfo.serial_no = ts->vinfo.serial_no | req[1];
348 
349  req[0] = TMA1217_MAX_X_HIGHER4;
350  retval = cp_tm1217_read(ts, req, 1);
351  ts->dinfo.maxX = (req[1] & 0xF) << 8;
352 
353  req[0] = TMA1217_MAX_X_LOWER8;
354  retval = cp_tm1217_read(ts, req, 1);
355  ts->dinfo.maxX = ts->dinfo.maxX | req[1];
356 
357  req[0] = TMA1217_MAX_Y_HIGHER4;
358  retval = cp_tm1217_read(ts, req, 1);
359  ts->dinfo.maxY = (req[1] & 0xF) << 8;
360 
361  req[0] = TMA1217_MAX_Y_LOWER8;
362  retval = cp_tm1217_read(ts, req, 1);
363  ts->dinfo.maxY = ts->dinfo.maxY | req[1];
364 
365  return 0;
366 
367 }
368 
369 /*
370  * Set up a GPIO for use as the interrupt. We can't simply do this at
371  * boot time because the GPIO drivers themselves may not be around at
372  * boot/firmware set up time to do the work. Instead defer it to driver
373  * detection.
374  */
375 
376 static int cp_tm1217_setup_gpio_irq(struct cp_tm1217_device *ts)
377 {
378  int retval;
379 
380  /* Hook up the irq handler */
381  retval = gpio_request(ts->gpio, "cp_tm1217_touch");
382  if (retval < 0) {
383  dev_err(ts->dev, "cp_tm1217: GPIO request failed error %d\n",
384  retval);
385  return retval;
386  }
387 
388  retval = gpio_direction_input(ts->gpio);
389  if (retval < 0) {
390  dev_err(ts->dev,
391  "cp_tm1217: GPIO direction configuration failed, error %d\n",
392  retval);
393  gpio_free(ts->gpio);
394  return retval;
395  }
396 
397  retval = gpio_to_irq(ts->gpio);
398  if (retval < 0) {
399  dev_err(ts->dev,
400  "cp_tm1217: GPIO to IRQ failed, error %d\n", retval);
401  gpio_free(ts->gpio);
402  }
403  dev_dbg(ts->dev,
404  "cp_tm1217: Got IRQ number is %d for GPIO %d\n",
405  retval, ts->gpio);
406  return retval;
407 }
408 
409 static int cp_tm1217_probe(struct i2c_client *client,
410  const struct i2c_device_id *id)
411 {
412  struct cp_tm1217_device *ts;
413  struct input_dev *input_dev;
414  struct input_dev_info *input_info;
416  u8 req[2];
417  int i, retval;
418 
419  /* No pdata is fine - we then use "normal" IRQ mode */
420 
421  pdata = client->dev.platform_data;
422 
423  ts = kzalloc(sizeof(struct cp_tm1217_device), GFP_KERNEL);
424  if (!ts) {
425  dev_err(&client->dev,
426  "cp_tm1217: Private Device Struct alloc failed\n");
427  return -ENOMEM;
428  }
429 
430  ts->client = client;
431  ts->dev = &client->dev;
432  i2c_set_clientdata(client, ts);
433 
434  ts->thread_running = 0;
435  mutex_init(&ts->thread_mutex);
436 
437  /* Reset the Controller */
438  req[0] = TMA1217_DEVICE_CMD_RESET;
439  req[1] = 0x1;
440  retval = cp_tm1217_write(ts, req, 1);
441  if (retval != 1) {
442  dev_err(ts->dev, "cp_tm1217: Controller reset failed\n");
443  kfree(ts);
444  return -EIO;
445  }
446 
447  /* Clear up the interrupt status from reset. */
448  req[0] = TMA1217_INT_STATUS;
449  retval = cp_tm1217_read(ts, req, 1);
450 
451  /* Mask all the interrupts */
452  retval = cp_tm1217_mask_interrupt(ts);
453 
454  /* Read the controller information */
455  cp_tm1217_init_data(ts);
456 
457  /* The following code will register multiple event devices when
458  multi-pointer is enabled, the code has not been tested
459  with MPX */
460  for (i = 0; i < TOUCH_SUPPORTED; i++) {
461  input_dev = input_allocate_device();
462  if (input_dev == NULL) {
463  dev_err(ts->dev,
464  "cp_tm1217:Input Device Struct alloc failed\n");
465  retval = -ENOMEM;
466  goto fail;
467  }
468  input_info = &ts->cp_input_info[i];
469  snprintf(input_info->name, sizeof(input_info->name),
470  "cp_tm1217_touchscreen_%d", i);
471  input_dev->name = input_info->name;
472  snprintf(input_info->phys, sizeof(input_info->phys),
473  "%s/input%d", dev_name(&client->dev), i);
474 
475  input_dev->phys = input_info->phys;
476  input_dev->id.bustype = BUS_I2C;
477 
478  input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
479  input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
480 
481  input_set_abs_params(input_dev, ABS_X, 0, ts->dinfo.maxX, 0, 0);
482  input_set_abs_params(input_dev, ABS_Y, 0, ts->dinfo.maxY, 0, 0);
483 
484  retval = input_register_device(input_dev);
485  if (retval) {
486  dev_err(ts->dev,
487  "Input dev registration failed for %s\n",
488  input_dev->name);
489  input_free_device(input_dev);
490  goto fail;
491  }
492  input_info->input = input_dev;
493  }
494 
495  /* Setup the reporting mode to send an interrupt only when
496  finger arrives or departs. */
497  req[0] = TMA1217_REPORT_MODE;
498  req[1] = 0x02;
499  retval = cp_tm1217_write(ts, req, 1);
500 
501  /* Setup the device to no sleep mode for now and make it configured */
502  req[0] = TMA1217_DEVICE_CTRL;
503  req[1] = 0x84;
504  retval = cp_tm1217_write(ts, req, 1);
505 
506  /* Check for the status of the device */
507  req[0] = TMA1217_DEV_STATUS;
508  retval = cp_tm1217_read(ts, req, 1);
509  if (req[1] != 0) {
510  dev_err(ts->dev,
511  "cp_tm1217: Device Status 0x%x != 0: config failed\n",
512  req[1]);
513 
514  retval = -EIO;
515  goto fail;
516  }
517 
518  if (pdata && pdata->gpio) {
519  ts->gpio = pdata->gpio;
520  retval = cp_tm1217_setup_gpio_irq(ts);
521  } else
522  retval = client->irq;
523 
524  if (retval < 0) {
525  dev_err(ts->dev, "cp_tm1217: GPIO request failed error %d\n",
526  retval);
527  goto fail;
528  }
529 
530  client->irq = retval;
531 
532 
533  retval = request_threaded_irq(client->irq,
534  NULL, cp_tm1217_sample_thread,
535  IRQF_TRIGGER_FALLING, "cp_tm1217_touch", ts);
536  if (retval < 0) {
537  dev_err(ts->dev, "cp_tm1217: Request IRQ error %d\n", retval);
538  goto fail_gpio;
539  }
540 
541  /* Unmask the interrupts */
542  retval = cp_tm1217_unmask_interrupt(ts);
543  if (retval == 0)
544  return 0;
545 
546  free_irq(client->irq, ts);
547 fail_gpio:
548  if (ts->gpio)
549  gpio_free(ts->gpio);
550 fail:
551  /* Clean up before returning failure */
552  for (i = 0; i < TOUCH_SUPPORTED; i++) {
553  if (ts->cp_input_info[i].input) {
554  input_unregister_device(ts->cp_input_info[i].input);
555  input_free_device(ts->cp_input_info[i].input);
556  }
557  }
558  kfree(ts);
559  return retval;
560 
561 }
562 
563 /*
564  * cp_tm1217 suspend
565  *
566  */
567 static int cp_tm1217_suspend(struct i2c_client *client, pm_message_t mesg)
568 {
569  struct cp_tm1217_device *ts = i2c_get_clientdata(client);
570  u8 req[2];
571  int retval;
572 
573  /* Put the controller to sleep */
574  req[0] = TMA1217_DEVICE_CTRL;
575  retval = cp_tm1217_read(ts, req, 1);
576  req[1] = (req[1] & 0xF8) | 0x1;
577  retval = cp_tm1217_write(ts, req, 1);
578 
579  if (device_may_wakeup(&client->dev))
580  enable_irq_wake(client->irq);
581 
582  return 0;
583 }
584 
585 /*
586  * cp_tm1217_resume
587  *
588  */
589 static int cp_tm1217_resume(struct i2c_client *client)
590 {
591  struct cp_tm1217_device *ts = i2c_get_clientdata(client);
592  u8 req[2];
593  int retval;
594 
595  /* Take the controller out of sleep */
596  req[0] = TMA1217_DEVICE_CTRL;
597  retval = cp_tm1217_read(ts, req, 1);
598  req[1] = (req[1] & 0xF8) | 0x4;
599  retval = cp_tm1217_write(ts, req, 1);
600 
601  /* Restore the register settings sinc the power to the
602  could have been cut off */
603 
604  /* Setup the reporting mode to send an interrupt only when
605  finger arrives or departs. */
606  req[0] = TMA1217_REPORT_MODE;
607  req[1] = 0x02;
608  retval = cp_tm1217_write(ts, req, 1);
609 
610  /* Setup the device to no sleep mode for now and make it configured */
611  req[0] = TMA1217_DEVICE_CTRL;
612  req[1] = 0x84;
613  retval = cp_tm1217_write(ts, req, 1);
614 
615  /* Setup the interrupt mask */
616  retval = cp_tm1217_unmask_interrupt(ts);
617 
618  if (device_may_wakeup(&client->dev))
619  disable_irq_wake(client->irq);
620 
621  return 0;
622 }
623 
624 /*
625  * cp_tm1217_remove
626  *
627  */
628 static int cp_tm1217_remove(struct i2c_client *client)
629 {
630  struct cp_tm1217_device *ts = i2c_get_clientdata(client);
631  int i;
632 
633  free_irq(client->irq, ts);
634  if (ts->gpio)
635  gpio_free(ts->gpio);
636  for (i = 0; i < TOUCH_SUPPORTED; i++)
637  input_unregister_device(ts->cp_input_info[i].input);
638  kfree(ts);
639  return 0;
640 }
641 
642 static struct i2c_device_id cp_tm1217_idtable[] = {
643  { CPTM1217_DEVICE_NAME, 0 },
644  { }
645 };
646 
647 MODULE_DEVICE_TABLE(i2c, cp_tm1217_idtable);
648 
649 static struct i2c_driver cp_tm1217_driver = {
650  .driver = {
651  .owner = THIS_MODULE,
652  .name = CPTM1217_DRIVER_NAME,
653  },
654  .id_table = cp_tm1217_idtable,
655  .probe = cp_tm1217_probe,
656  .remove = cp_tm1217_remove,
657  .suspend = cp_tm1217_suspend,
658  .resume = cp_tm1217_resume,
659 };
660 
661 module_i2c_driver(cp_tm1217_driver);
662 
663 MODULE_AUTHOR("Ramesh Agarwal <[email protected]>");
664 MODULE_DESCRIPTION("Synaptics TM1217 TouchScreen Driver");
665 MODULE_LICENSE("GPL v2");