1 /*
2  * Core Source for:
3  * Cypress TrueTouch(TM) Standard Product (TTSP) touchscreen drivers.
4  * For use with Cypress Txx3xx parts.
5  * Supported parts include:
6  * CY8CTST341
7  * CY8CTMA340
8  *
9  * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
10  * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * version 2, and only version 2, as published by the
15  * Free Software Foundation.
16  *
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.
21  *
22  * You should have received a copy of the GNU General Public License along
23  * with this program; if not, write to the Free Software Foundation, Inc.,
24  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
25  *
26  * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
27  *
28  */
29 
30 #include <linux/delay.h>
31 #include <linux/input.h>
32 #include <linux/input/mt.h>
33 #include <linux/gpio.h>
34 #include <linux/interrupt.h>
35 #include <linux/slab.h>
36 
37 #include "cyttsp_core.h"
38 
39 /* Bootloader number of command keys */
40 #define CY_NUM_BL_KEYS		8
41 
42 /* helpers */
43 #define GET_NUM_TOUCHES(x)		((x) & 0x0F)
44 #define IS_LARGE_AREA(x)		(((x) & 0x10) >> 4)
45 #define IS_BAD_PKT(x)			((x) & 0x20)
46 #define IS_VALID_APP(x)			((x) & 0x01)
47 #define IS_OPERATIONAL_ERR(x)		((x) & 0x3F)
48 #define GET_HSTMODE(reg)		(((reg) & 0x70) >> 4)
49 #define GET_BOOTLOADERMODE(reg)		(((reg) & 0x10) >> 4)
50 
51 #define CY_REG_BASE			0x00
52 #define CY_REG_ACT_DIST			0x1E
53 #define CY_REG_ACT_INTRVL		0x1D
54 #define CY_REG_TCH_TMOUT		(CY_REG_ACT_INTRVL + 1)
55 #define CY_REG_LP_INTRVL		(CY_REG_TCH_TMOUT + 1)
56 #define CY_MAXZ				255
57 #define CY_DELAY_DFLT			20 /* ms */
58 #define CY_DELAY_MAX			500
59 #define CY_ACT_DIST_DFLT		0xF8
60 #define CY_HNDSHK_BIT			0x80
61 /* device mode bits */
62 #define CY_OPERATE_MODE			0x00
63 #define CY_SYSINFO_MODE			0x10
64 /* power mode select bits */
65 #define CY_SOFT_RESET_MODE		0x01 /* return to Bootloader mode */
66 #define CY_DEEP_SLEEP_MODE		0x02
67 #define CY_LOW_POWER_MODE		0x04
68 
69 /* Slots management */
70 #define CY_MAX_FINGER			4
71 #define CY_MAX_ID			16
72 
73 static const u8 bl_command[] = {
74 	0x00,			/* file offset */
75 	0xFF,			/* command */
76 	0xA5,			/* exit bootloader command */
77 	0, 1, 2, 3, 4, 5, 6, 7	/* default keys */
78 };
79 
80 static int ttsp_read_block_data(struct cyttsp *ts, u8 command,
81 				u8 length, void *buf)
82 {
83 	int error;
84 	int tries;
85 
86 	for (tries = 0; tries < CY_NUM_RETRY; tries++) {
87 		error = ts->bus_ops->read(ts, command, length, buf);
88 		if (!error)
89 			return 0;
90 
91 		msleep(CY_DELAY_DFLT);
92 	}
93 
94 	return -EIO;
95 }
96 
97 static int ttsp_write_block_data(struct cyttsp *ts, u8 command,
98 				 u8 length, void *buf)
99 {
100 	int error;
101 	int tries;
102 
103 	for (tries = 0; tries < CY_NUM_RETRY; tries++) {
104 		error = ts->bus_ops->write(ts, command, length, buf);
105 		if (!error)
106 			return 0;
107 
108 		msleep(CY_DELAY_DFLT);
109 	}
110 
111 	return -EIO;
112 }
113 
114 static int ttsp_send_command(struct cyttsp *ts, u8 cmd)
115 {
116 	return ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
117 }
118 
119 static int cyttsp_handshake(struct cyttsp *ts)
120 {
121 	if (ts->pdata->use_hndshk)
122 		return ttsp_send_command(ts,
123 				ts->xy_data.hst_mode ^ CY_HNDSHK_BIT);
124 
125 	return 0;
126 }
127 
128 static int cyttsp_load_bl_regs(struct cyttsp *ts)
129 {
130 	memset(&ts->bl_data, 0, sizeof(ts->bl_data));
131 	ts->bl_data.bl_status = 0x10;
132 
133 	return ttsp_read_block_data(ts, CY_REG_BASE,
134 				    sizeof(ts->bl_data), &ts->bl_data);
135 }
136 
137 static int cyttsp_exit_bl_mode(struct cyttsp *ts)
138 {
139 	int error;
140 	u8 bl_cmd[sizeof(bl_command)];
141 
142 	memcpy(bl_cmd, bl_command, sizeof(bl_command));
143 	if (ts->pdata->bl_keys)
144 		memcpy(&bl_cmd[sizeof(bl_command) - CY_NUM_BL_KEYS],
145 			ts->pdata->bl_keys, CY_NUM_BL_KEYS);
146 
147 	error = ttsp_write_block_data(ts, CY_REG_BASE,
148 				      sizeof(bl_cmd), bl_cmd);
149 	if (error)
150 		return error;
151 
152 	/* wait for TTSP Device to complete the operation */
153 	msleep(CY_DELAY_DFLT);
154 
155 	error = cyttsp_load_bl_regs(ts);
156 	if (error)
157 		return error;
158 
159 	if (GET_BOOTLOADERMODE(ts->bl_data.bl_status))
160 		return -EIO;
161 
162 	return 0;
163 }
164 
165 static int cyttsp_set_operational_mode(struct cyttsp *ts)
166 {
167 	int error;
168 
169 	error = ttsp_send_command(ts, CY_OPERATE_MODE);
170 	if (error)
171 		return error;
172 
173 	/* wait for TTSP Device to complete switch to Operational mode */
174 	error = ttsp_read_block_data(ts, CY_REG_BASE,
175 				     sizeof(ts->xy_data), &ts->xy_data);
176 	if (error)
177 		return error;
178 
179 	error = cyttsp_handshake(ts);
180 	if (error)
181 		return error;
182 
183 	return ts->xy_data.act_dist == CY_ACT_DIST_DFLT ? -EIO : 0;
184 }
185 
186 static int cyttsp_set_sysinfo_mode(struct cyttsp *ts)
187 {
188 	int error;
189 
190 	memset(&ts->sysinfo_data, 0, sizeof(ts->sysinfo_data));
191 
192 	/* switch to sysinfo mode */
193 	error = ttsp_send_command(ts, CY_SYSINFO_MODE);
194 	if (error)
195 		return error;
196 
197 	/* read sysinfo registers */
198 	msleep(CY_DELAY_DFLT);
199 	error = ttsp_read_block_data(ts, CY_REG_BASE, sizeof(ts->sysinfo_data),
200 				      &ts->sysinfo_data);
201 	if (error)
202 		return error;
203 
204 	error = cyttsp_handshake(ts);
205 	if (error)
206 		return error;
207 
208 	if (!ts->sysinfo_data.tts_verh && !ts->sysinfo_data.tts_verl)
209 		return -EIO;
210 
211 	return 0;
212 }
213 
214 static int cyttsp_set_sysinfo_regs(struct cyttsp *ts)
215 {
216 	int retval = 0;
217 
218 	if (ts->pdata->act_intrvl != CY_ACT_INTRVL_DFLT ||
219 	    ts->pdata->tch_tmout != CY_TCH_TMOUT_DFLT ||
220 	    ts->pdata->lp_intrvl != CY_LP_INTRVL_DFLT) {
221 
222 		u8 intrvl_ray[] = {
223 			ts->pdata->act_intrvl,
224 			ts->pdata->tch_tmout,
225 			ts->pdata->lp_intrvl
226 		};
227 
228 		/* set intrvl registers */
229 		retval = ttsp_write_block_data(ts, CY_REG_ACT_INTRVL,
230 					sizeof(intrvl_ray), intrvl_ray);
231 		msleep(CY_DELAY_DFLT);
232 	}
233 
234 	return retval;
235 }
236 
237 static int cyttsp_soft_reset(struct cyttsp *ts)
238 {
239 	unsigned long timeout;
240 	int retval;
241 
242 	/* wait for interrupt to set ready completion */
243 	INIT_COMPLETION(ts->bl_ready);
244 	ts->state = CY_BL_STATE;
245 
246 	enable_irq(ts->irq);
247 
248 	retval = ttsp_send_command(ts, CY_SOFT_RESET_MODE);
249 	if (retval)
250 		goto out;
251 
252 	timeout = wait_for_completion_timeout(&ts->bl_ready,
253 			msecs_to_jiffies(CY_DELAY_DFLT * CY_DELAY_MAX));
254 	retval = timeout ? 0 : -EIO;
255 
256 out:
257 	ts->state = CY_IDLE_STATE;
258 	disable_irq(ts->irq);
259 	return retval;
260 }
261 
262 static int cyttsp_act_dist_setup(struct cyttsp *ts)
263 {
264 	u8 act_dist_setup = ts->pdata->act_dist;
265 
266 	/* Init gesture; active distance setup */
267 	return ttsp_write_block_data(ts, CY_REG_ACT_DIST,
268 				sizeof(act_dist_setup), &act_dist_setup);
269 }
270 
271 static void cyttsp_extract_track_ids(struct cyttsp_xydata *xy_data, int *ids)
272 {
273 	ids[0] = xy_data->touch12_id >> 4;
274 	ids[1] = xy_data->touch12_id & 0xF;
275 	ids[2] = xy_data->touch34_id >> 4;
276 	ids[3] = xy_data->touch34_id & 0xF;
277 }
278 
279 static const struct cyttsp_tch *cyttsp_get_tch(struct cyttsp_xydata *xy_data,
280 					       int idx)
281 {
282 	switch (idx) {
283 	case 0:
284 		return &xy_data->tch1;
285 	case 1:
286 		return &xy_data->tch2;
287 	case 2:
288 		return &xy_data->tch3;
289 	case 3:
290 		return &xy_data->tch4;
291 	default:
292 		return NULL;
293 	}
294 }
295 
296 static void cyttsp_report_tchdata(struct cyttsp *ts)
297 {
298 	struct cyttsp_xydata *xy_data = &ts->xy_data;
299 	struct input_dev *input = ts->input;
300 	int num_tch = GET_NUM_TOUCHES(xy_data->tt_stat);
301 	const struct cyttsp_tch *tch;
302 	int ids[CY_MAX_ID];
303 	int i;
304 	DECLARE_BITMAP(used, CY_MAX_ID);
305 
306 	if (IS_LARGE_AREA(xy_data->tt_stat) == 1) {
307 		/* terminate all active tracks */
308 		num_tch = 0;
309 		dev_dbg(ts->dev, "%s: Large area detected\n", __func__);
310 	} else if (num_tch > CY_MAX_FINGER) {
311 		/* terminate all active tracks */
312 		num_tch = 0;
313 		dev_dbg(ts->dev, "%s: Num touch error detected\n", __func__);
314 	} else if (IS_BAD_PKT(xy_data->tt_mode)) {
315 		/* terminate all active tracks */
316 		num_tch = 0;
317 		dev_dbg(ts->dev, "%s: Invalid buffer detected\n", __func__);
318 	}
319 
320 	cyttsp_extract_track_ids(xy_data, ids);
321 
322 	bitmap_zero(used, CY_MAX_ID);
323 
324 	for (i = 0; i < num_tch; i++) {
325 		tch = cyttsp_get_tch(xy_data, i);
326 
327 		input_mt_slot(input, ids[i]);
328 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
329 		input_report_abs(input, ABS_MT_POSITION_X, be16_to_cpu(tch->x));
330 		input_report_abs(input, ABS_MT_POSITION_Y, be16_to_cpu(tch->y));
331 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, tch->z);
332 
333 		__set_bit(ids[i], used);
334 	}
335 
336 	for (i = 0; i < CY_MAX_ID; i++) {
337 		if (test_bit(i, used))
338 			continue;
339 
340 		input_mt_slot(input, i);
341 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
342 	}
343 
344 	input_sync(input);
345 }
346 
347 static irqreturn_t cyttsp_irq(int irq, void *handle)
348 {
349 	struct cyttsp *ts = handle;
350 	int error;
351 
352 	if (unlikely(ts->state == CY_BL_STATE)) {
353 		complete(&ts->bl_ready);
354 		goto out;
355 	}
356 
357 	/* Get touch data from CYTTSP device */
358 	error = ttsp_read_block_data(ts, CY_REG_BASE,
359 				 sizeof(struct cyttsp_xydata), &ts->xy_data);
360 	if (error)
361 		goto out;
362 
363 	/* provide flow control handshake */
364 	error = cyttsp_handshake(ts);
365 	if (error)
366 		goto out;
367 
368 	if (unlikely(ts->state == CY_IDLE_STATE))
369 		goto out;
370 
371 	if (GET_BOOTLOADERMODE(ts->xy_data.tt_mode)) {
372 		/*
373 		 * TTSP device has reset back to bootloader mode.
374 		 * Restore to operational mode.
375 		 */
376 		error = cyttsp_exit_bl_mode(ts);
377 		if (error) {
378 			dev_err(ts->dev,
379 				"Could not return to operational mode, err: %d\n",
380 				error);
381 			ts->state = CY_IDLE_STATE;
382 		}
383 	} else {
384 		cyttsp_report_tchdata(ts);
385 	}
386 
387 out:
388 	return IRQ_HANDLED;
389 }
390 
391 static int cyttsp_power_on(struct cyttsp *ts)
392 {
393 	int error;
394 
395 	error = cyttsp_soft_reset(ts);
396 	if (error)
397 		return error;
398 
399 	error = cyttsp_load_bl_regs(ts);
400 	if (error)
401 		return error;
402 
403 	if (GET_BOOTLOADERMODE(ts->bl_data.bl_status) &&
404 	    IS_VALID_APP(ts->bl_data.bl_status)) {
405 		error = cyttsp_exit_bl_mode(ts);
406 		if (error)
407 			return error;
408 	}
409 
410 	if (GET_HSTMODE(ts->bl_data.bl_file) != CY_OPERATE_MODE ||
411 	    IS_OPERATIONAL_ERR(ts->bl_data.bl_status)) {
412 		return -ENODEV;
413 	}
414 
415 	error = cyttsp_set_sysinfo_mode(ts);
416 	if (error)
417 		return error;
418 
419 	error = cyttsp_set_sysinfo_regs(ts);
420 	if (error)
421 		return error;
422 
423 	error = cyttsp_set_operational_mode(ts);
424 	if (error)
425 		return error;
426 
427 	/* init active distance */
428 	error = cyttsp_act_dist_setup(ts);
429 	if (error)
430 		return error;
431 
432 	ts->state = CY_ACTIVE_STATE;
433 
434 	return 0;
435 }
436 
437 static int cyttsp_enable(struct cyttsp *ts)
438 {
439 	int error;
440 
441 	/*
442 	 * The device firmware can wake on an I2C or SPI memory slave
443 	 * address match. So just reading a register is sufficient to
444 	 * wake up the device. The first read attempt will fail but it
445 	 * will wake it up making the second read attempt successful.
446 	 */
447 	error = ttsp_read_block_data(ts, CY_REG_BASE,
448 				     sizeof(ts->xy_data), &ts->xy_data);
449 	if (error)
450 		return error;
451 
452 	if (GET_HSTMODE(ts->xy_data.hst_mode))
453 		return -EIO;
454 
455 	enable_irq(ts->irq);
456 
457 	return 0;
458 }
459 
460 static int cyttsp_disable(struct cyttsp *ts)
461 {
462 	int error;
463 
464 	error = ttsp_send_command(ts, CY_LOW_POWER_MODE);
465 	if (error)
466 		return error;
467 
468 	disable_irq(ts->irq);
469 
470 	return 0;
471 }
472 
473 #ifdef CONFIG_PM_SLEEP
474 static int cyttsp_suspend(struct device *dev)
475 {
476 	struct cyttsp *ts = dev_get_drvdata(dev);
477 	int retval = 0;
478 
479 	mutex_lock(&ts->input->mutex);
480 
481 	if (ts->input->users) {
482 		retval = cyttsp_disable(ts);
483 		if (retval == 0)
484 			ts->suspended = true;
485 	}
486 
487 	mutex_unlock(&ts->input->mutex);
488 
489 	return retval;
490 }
491 
492 static int cyttsp_resume(struct device *dev)
493 {
494 	struct cyttsp *ts = dev_get_drvdata(dev);
495 
496 	mutex_lock(&ts->input->mutex);
497 
498 	if (ts->input->users)
499 		cyttsp_enable(ts);
500 
501 	ts->suspended = false;
502 
503 	mutex_unlock(&ts->input->mutex);
504 
505 	return 0;
506 }
507 
508 #endif
509 
510 SIMPLE_DEV_PM_OPS(cyttsp_pm_ops, cyttsp_suspend, cyttsp_resume);
511 EXPORT_SYMBOL_GPL(cyttsp_pm_ops);
512 
513 static int cyttsp_open(struct input_dev *dev)
514 {
515 	struct cyttsp *ts = input_get_drvdata(dev);
516 	int retval = 0;
517 
518 	if (!ts->suspended)
519 		retval = cyttsp_enable(ts);
520 
521 	return retval;
522 }
523 
524 static void cyttsp_close(struct input_dev *dev)
525 {
526 	struct cyttsp *ts = input_get_drvdata(dev);
527 
528 	if (!ts->suspended)
529 		cyttsp_disable(ts);
530 }
531 
532 struct cyttsp *cyttsp_probe(const struct cyttsp_bus_ops *bus_ops,
533 			    struct device *dev, int irq, size_t xfer_buf_size)
534 {
535 	const struct cyttsp_platform_data *pdata = dev->platform_data;
536 	struct cyttsp *ts;
537 	struct input_dev *input_dev;
538 	int error;
539 
540 	if (!pdata || !pdata->name || irq <= 0) {
541 		error = -EINVAL;
542 		goto err_out;
543 	}
544 
545 	ts = kzalloc(sizeof(*ts) + xfer_buf_size, GFP_KERNEL);
546 	input_dev = input_allocate_device();
547 	if (!ts || !input_dev) {
548 		error = -ENOMEM;
549 		goto err_free_mem;
550 	}
551 
552 	ts->dev = dev;
553 	ts->input = input_dev;
554 	ts->pdata = dev->platform_data;
555 	ts->bus_ops = bus_ops;
556 	ts->irq = irq;
557 
558 	init_completion(&ts->bl_ready);
559 	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
560 
561 	if (pdata->init) {
562 		error = pdata->init();
563 		if (error) {
564 			dev_err(ts->dev, "platform init failed, err: %d\n",
565 				error);
566 			goto err_free_mem;
567 		}
568 	}
569 
570 	input_dev->name = pdata->name;
571 	input_dev->phys = ts->phys;
572 	input_dev->id.bustype = bus_ops->bustype;
573 	input_dev->dev.parent = ts->dev;
574 
575 	input_dev->open = cyttsp_open;
576 	input_dev->close = cyttsp_close;
577 
578 	input_set_drvdata(input_dev, ts);
579 
580 	__set_bit(EV_ABS, input_dev->evbit);
581 	input_set_abs_params(input_dev, ABS_MT_POSITION_X,
582 			     0, pdata->maxx, 0, 0);
583 	input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
584 			     0, pdata->maxy, 0, 0);
585 	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
586 			     0, CY_MAXZ, 0, 0);
587 
588 	input_mt_init_slots(input_dev, CY_MAX_ID, 0);
589 
590 	error = request_threaded_irq(ts->irq, NULL, cyttsp_irq,
591 				     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
592 				     pdata->name, ts);
593 	if (error) {
594 		dev_err(ts->dev, "failed to request IRQ %d, err: %d\n",
595 			ts->irq, error);
596 		goto err_platform_exit;
597 	}
598 
599 	disable_irq(ts->irq);
600 
601 	error = cyttsp_power_on(ts);
602 	if (error)
603 		goto err_free_irq;
604 
605 	error = input_register_device(input_dev);
606 	if (error) {
607 		dev_err(ts->dev, "failed to register input device: %d\n",
608 			error);
609 		goto err_free_irq;
610 	}
611 
612 	return ts;
613 
614 err_free_irq:
615 	free_irq(ts->irq, ts);
616 err_platform_exit:
617 	if (pdata->exit)
618 		pdata->exit();
619 err_free_mem:
620 	input_free_device(input_dev);
621 	kfree(ts);
622 err_out:
623 	return ERR_PTR(error);
624 }
625 EXPORT_SYMBOL_GPL(cyttsp_probe);
626 
627 void cyttsp_remove(struct cyttsp *ts)
628 {
629 	free_irq(ts->irq, ts);
630 	input_unregister_device(ts->input);
631 	if (ts->pdata->exit)
632 		ts->pdata->exit();
633 	kfree(ts);
634 }
635 EXPORT_SYMBOL_GPL(cyttsp_remove);
636 
637 MODULE_LICENSE("GPL");
638 MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard touchscreen driver core");
639 MODULE_AUTHOR("Cypress");
640