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Input: dlink-dir685-touchkeys - fix a typo in driver name
[linux/fpc-iii.git] / drivers / input / touchscreen / ti_am335x_tsc.c
blobb86c1e5fbc115dcbd30082919ae6c12f2b4e4ea2
1 /*
2 * TI Touch Screen driver
3 *
4 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation version 2.
9 *
10 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11 * kind, whether express or implied; without even the implied warranty
12 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16
17 #include <linux/kernel.h>
18 #include <linux/err.h>
19 #include <linux/module.h>
20 #include <linux/input.h>
21 #include <linux/slab.h>
22 #include <linux/interrupt.h>
23 #include <linux/clk.h>
24 #include <linux/platform_device.h>
25 #include <linux/io.h>
26 #include <linux/delay.h>
27 #include <linux/of.h>
28 #include <linux/of_device.h>
29 #include <linux/sort.h>
30
31 #include <linux/mfd/ti_am335x_tscadc.h>
32
33 #define ADCFSM_STEPID 0x10
34 #define SEQ_SETTLE 275
35 #define MAX_12BIT ((1 << 12) - 1)
36
37 #define TSC_IRQENB_MASK (IRQENB_FIFO0THRES | IRQENB_EOS | IRQENB_HW_PEN)
38
39 static const int config_pins[] = {
40 STEPCONFIG_XPP,
41 STEPCONFIG_XNN,
42 STEPCONFIG_YPP,
43 STEPCONFIG_YNN,
44 };
45
46 struct titsc {
47 struct input_dev *input;
48 struct ti_tscadc_dev *mfd_tscadc;
49 unsigned int irq;
50 unsigned int wires;
51 unsigned int x_plate_resistance;
52 bool pen_down;
53 int coordinate_readouts;
54 u32 config_inp[4];
55 u32 bit_xp, bit_xn, bit_yp, bit_yn;
56 u32 inp_xp, inp_xn, inp_yp, inp_yn;
57 u32 step_mask;
58 u32 charge_delay;
59 };
60
61 static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
62 {
63 return readl(ts->mfd_tscadc->tscadc_base + reg);
64 }
65
66 static void titsc_writel(struct titsc *tsc, unsigned int reg,
67 unsigned int val)
68 {
69 writel(val, tsc->mfd_tscadc->tscadc_base + reg);
70 }
71
72 static int titsc_config_wires(struct titsc *ts_dev)
73 {
74 u32 analog_line[4];
75 u32 wire_order[4];
76 int i, bit_cfg;
77
78 for (i = 0; i < 4; i++) {
79 /*
80 * Get the order in which TSC wires are attached
81 * w.r.t. each of the analog input lines on the EVM.
82 */
83 analog_line[i] = (ts_dev->config_inp[i] & 0xF0) >> 4;
84 wire_order[i] = ts_dev->config_inp[i] & 0x0F;
85 if (WARN_ON(analog_line[i] > 7))
86 return -EINVAL;
87 if (WARN_ON(wire_order[i] > ARRAY_SIZE(config_pins)))
88 return -EINVAL;
89 }
90
91 for (i = 0; i < 4; i++) {
92 int an_line;
93 int wi_order;
94
95 an_line = analog_line[i];
96 wi_order = wire_order[i];
97 bit_cfg = config_pins[wi_order];
98 if (bit_cfg == 0)
99 return -EINVAL;
100 switch (wi_order) {
101 case 0:
102 ts_dev->bit_xp = bit_cfg;
103 ts_dev->inp_xp = an_line;
104 break;
105
106 case 1:
107 ts_dev->bit_xn = bit_cfg;
108 ts_dev->inp_xn = an_line;
109 break;
110
111 case 2:
112 ts_dev->bit_yp = bit_cfg;
113 ts_dev->inp_yp = an_line;
114 break;
115 case 3:
116 ts_dev->bit_yn = bit_cfg;
117 ts_dev->inp_yn = an_line;
118 break;
119 }
120 }
121 return 0;
122 }
123
124 static void titsc_step_config(struct titsc *ts_dev)
125 {
126 unsigned int config;
127 int i;
128 int end_step, first_step, tsc_steps;
129 u32 stepenable;
130
131 config = STEPCONFIG_MODE_HWSYNC |
132 STEPCONFIG_AVG_16 | ts_dev->bit_xp;
133 switch (ts_dev->wires) {
134 case 4:
135 config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn;
136 break;
137 case 5:
138 config |= ts_dev->bit_yn |
139 STEPCONFIG_INP_AN4 | ts_dev->bit_xn |
140 ts_dev->bit_yp;
141 break;
142 case 8:
143 config |= STEPCONFIG_INP(ts_dev->inp_yp) | ts_dev->bit_xn;
144 break;
145 }
146
147 tsc_steps = ts_dev->coordinate_readouts * 2 + 2;
148 first_step = TOTAL_STEPS - tsc_steps;
149 /* Steps 16 to 16-coordinate_readouts is for X */
150 end_step = first_step + tsc_steps;
151 for (i = end_step - ts_dev->coordinate_readouts; i < end_step; i++) {
152 titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
153 titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
154 }
155
156 config = 0;
157 config = STEPCONFIG_MODE_HWSYNC |
158 STEPCONFIG_AVG_16 | ts_dev->bit_yn |
159 STEPCONFIG_INM_ADCREFM;
160 switch (ts_dev->wires) {
161 case 4:
162 config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp);
163 break;
164 case 5:
165 config |= ts_dev->bit_xp | STEPCONFIG_INP_AN4 |
166 STEPCONFIG_XNP | STEPCONFIG_YPN;
167 break;
168 case 8:
169 config |= ts_dev->bit_yp | STEPCONFIG_INP(ts_dev->inp_xp);
170 break;
171 }
172
173 /* 1 ... coordinate_readouts is for Y */
174 end_step = first_step + ts_dev->coordinate_readouts;
175 for (i = first_step; i < end_step; i++) {
176 titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
177 titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
178 }
179
180 /* Make CHARGECONFIG same as IDLECONFIG */
181
182 config = titsc_readl(ts_dev, REG_IDLECONFIG);
183 titsc_writel(ts_dev, REG_CHARGECONFIG, config);
184 titsc_writel(ts_dev, REG_CHARGEDELAY, ts_dev->charge_delay);
185
186 /* coordinate_readouts + 1 ... coordinate_readouts + 2 is for Z */
187 config = STEPCONFIG_MODE_HWSYNC |
188 STEPCONFIG_AVG_16 | ts_dev->bit_yp |
189 ts_dev->bit_xn | STEPCONFIG_INM_ADCREFM |
190 STEPCONFIG_INP(ts_dev->inp_xp);
191 titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
192 titsc_writel(ts_dev, REG_STEPDELAY(end_step),
193 STEPCONFIG_OPENDLY);
194
195 end_step++;
196 config |= STEPCONFIG_INP(ts_dev->inp_yn);
197 titsc_writel(ts_dev, REG_STEPCONFIG(end_step), config);
198 titsc_writel(ts_dev, REG_STEPDELAY(end_step),
199 STEPCONFIG_OPENDLY);
200
201 /* The steps end ... end - readouts * 2 + 2 and bit 0 for TS_Charge */
202 stepenable = 1;
203 for (i = 0; i < tsc_steps; i++)
204 stepenable |= 1 << (first_step + i + 1);
205
206 ts_dev->step_mask = stepenable;
207 am335x_tsc_se_set_cache(ts_dev->mfd_tscadc, ts_dev->step_mask);
208 }
209
210 static int titsc_cmp_coord(const void *a, const void *b)
211 {
212 return *(int *)a - *(int *)b;
213 }
214
215 static void titsc_read_coordinates(struct titsc *ts_dev,
216 u32 *x, u32 *y, u32 *z1, u32 *z2)
217 {
218 unsigned int yvals[7], xvals[7];
219 unsigned int i, xsum = 0, ysum = 0;
220 unsigned int creads = ts_dev->coordinate_readouts;
221
222 for (i = 0; i < creads; i++) {
223 yvals[i] = titsc_readl(ts_dev, REG_FIFO0);
224 yvals[i] &= 0xfff;
225 }
226
227 *z1 = titsc_readl(ts_dev, REG_FIFO0);
228 *z1 &= 0xfff;
229 *z2 = titsc_readl(ts_dev, REG_FIFO0);
230 *z2 &= 0xfff;
231
232 for (i = 0; i < creads; i++) {
233 xvals[i] = titsc_readl(ts_dev, REG_FIFO0);
234 xvals[i] &= 0xfff;
235 }
236
237 /*
238 * If co-ordinates readouts is less than 4 then
239 * report the average. In case of 4 or more
240 * readouts, sort the co-ordinate samples, drop
241 * min and max values and report the average of
242 * remaining values.
243 */
244 if (creads <= 3) {
245 for (i = 0; i < creads; i++) {
246 ysum += yvals[i];
247 xsum += xvals[i];
248 }
249 ysum /= creads;
250 xsum /= creads;
251 } else {
252 sort(yvals, creads, sizeof(unsigned int),
253 titsc_cmp_coord, NULL);
254 sort(xvals, creads, sizeof(unsigned int),
255 titsc_cmp_coord, NULL);
256 for (i = 1; i < creads - 1; i++) {
257 ysum += yvals[i];
258 xsum += xvals[i];
259 }
260 ysum /= creads - 2;
261 xsum /= creads - 2;
262 }
263 *y = ysum;
264 *x = xsum;
265 }
266
267 static irqreturn_t titsc_irq(int irq, void *dev)
268 {
269 struct titsc *ts_dev = dev;
270 struct input_dev *input_dev = ts_dev->input;
271 unsigned int fsm, status, irqclr = 0;
272 unsigned int x = 0, y = 0;
273 unsigned int z1, z2, z;
274
275 status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
276 if (status & IRQENB_HW_PEN) {
277 ts_dev->pen_down = true;
278 irqclr |= IRQENB_HW_PEN;
279 pm_stay_awake(ts_dev->mfd_tscadc->dev);
280 }
281
282 if (status & IRQENB_PENUP) {
283 fsm = titsc_readl(ts_dev, REG_ADCFSM);
284 if (fsm == ADCFSM_STEPID) {
285 ts_dev->pen_down = false;
286 input_report_key(input_dev, BTN_TOUCH, 0);
287 input_report_abs(input_dev, ABS_PRESSURE, 0);
288 input_sync(input_dev);
289 pm_relax(ts_dev->mfd_tscadc->dev);
290 } else {
291 ts_dev->pen_down = true;
292 }
293 irqclr |= IRQENB_PENUP;
294 }
295
296 if (status & IRQENB_EOS)
297 irqclr |= IRQENB_EOS;
298
299 /*
300 * ADC and touchscreen share the IRQ line.
301 * FIFO1 interrupts are used by ADC. Handle FIFO0 IRQs here only
302 */
303 if (status & IRQENB_FIFO0THRES) {
304
305 titsc_read_coordinates(ts_dev, &x, &y, &z1, &z2);
306
307 if (ts_dev->pen_down && z1 != 0 && z2 != 0) {
308 /*
309 * Calculate pressure using formula
310 * Resistance(touch) = x plate resistance *
311 * x postion/4096 * ((z2 / z1) - 1)
312 */
313 z = z1 - z2;
314 z *= x;
315 z *= ts_dev->x_plate_resistance;
316 z /= z2;
317 z = (z + 2047) >> 12;
318
319 if (z <= MAX_12BIT) {
320 input_report_abs(input_dev, ABS_X, x);
321 input_report_abs(input_dev, ABS_Y, y);
322 input_report_abs(input_dev, ABS_PRESSURE, z);
323 input_report_key(input_dev, BTN_TOUCH, 1);
324 input_sync(input_dev);
325 }
326 }
327 irqclr |= IRQENB_FIFO0THRES;
328 }
329 if (irqclr) {
330 titsc_writel(ts_dev, REG_IRQSTATUS, irqclr);
331 if (status & IRQENB_EOS)
332 am335x_tsc_se_set_cache(ts_dev->mfd_tscadc,
333 ts_dev->step_mask);
334 return IRQ_HANDLED;
335 }
336 return IRQ_NONE;
337 }
338
339 static int titsc_parse_dt(struct platform_device *pdev,
340 struct titsc *ts_dev)
341 {
342 struct device_node *node = pdev->dev.of_node;
343 int err;
344
345 if (!node)
346 return -EINVAL;
347
348 err = of_property_read_u32(node, "ti,wires", &ts_dev->wires);
349 if (err < 0)
350 return err;
351 switch (ts_dev->wires) {
352 case 4:
353 case 5:
354 case 8:
355 break;
356 default:
357 return -EINVAL;
358 }
359
360 err = of_property_read_u32(node, "ti,x-plate-resistance",
361 &ts_dev->x_plate_resistance);
362 if (err < 0)
363 return err;
364
365 /*
366 * Try with the new binding first. If it fails, try again with
367 * bogus, miss-spelled version.
368 */
369 err = of_property_read_u32(node, "ti,coordinate-readouts",
370 &ts_dev->coordinate_readouts);
371 if (err < 0) {
372 dev_warn(&pdev->dev, "please use 'ti,coordinate-readouts' instead\n");
373 err = of_property_read_u32(node, "ti,coordiante-readouts",
374 &ts_dev->coordinate_readouts);
375 }
376
377 if (err < 0)
378 return err;
379
380 if (ts_dev->coordinate_readouts <= 0) {
381 dev_warn(&pdev->dev,
382 "invalid co-ordinate readouts, resetting it to 5\n");
383 ts_dev->coordinate_readouts = 5;
384 }
385
386 err = of_property_read_u32(node, "ti,charge-delay",
387 &ts_dev->charge_delay);
388 /*
389 * If ti,charge-delay value is not specified, then use
390 * CHARGEDLY_OPENDLY as the default value.
391 */
392 if (err < 0) {
393 ts_dev->charge_delay = CHARGEDLY_OPENDLY;
394 dev_warn(&pdev->dev, "ti,charge-delay not specified\n");
395 }
396
397 return of_property_read_u32_array(node, "ti,wire-config",
398 ts_dev->config_inp, ARRAY_SIZE(ts_dev->config_inp));
399 }
400
401 /*
402 * The functions for inserting/removing driver as a module.
403 */
404
405 static int titsc_probe(struct platform_device *pdev)
406 {
407 struct titsc *ts_dev;
408 struct input_dev *input_dev;
409 struct ti_tscadc_dev *tscadc_dev = ti_tscadc_dev_get(pdev);
410 int err;
411
412 /* Allocate memory for device */
413 ts_dev = kzalloc(sizeof(*ts_dev), GFP_KERNEL);
414 input_dev = input_allocate_device();
415 if (!ts_dev || !input_dev) {
416 dev_err(&pdev->dev, "failed to allocate memory.\n");
417 err = -ENOMEM;
418 goto err_free_mem;
419 }
420
421 tscadc_dev->tsc = ts_dev;
422 ts_dev->mfd_tscadc = tscadc_dev;
423 ts_dev->input = input_dev;
424 ts_dev->irq = tscadc_dev->irq;
425
426 err = titsc_parse_dt(pdev, ts_dev);
427 if (err) {
428 dev_err(&pdev->dev, "Could not find valid DT data.\n");
429 goto err_free_mem;
430 }
431
432 err = request_irq(ts_dev->irq, titsc_irq,
433 IRQF_SHARED, pdev->dev.driver->name, ts_dev);
434 if (err) {
435 dev_err(&pdev->dev, "failed to allocate irq.\n");
436 goto err_free_mem;
437 }
438
439 titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
440 titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
441 titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_EOS);
442 err = titsc_config_wires(ts_dev);
443 if (err) {
444 dev_err(&pdev->dev, "wrong i/p wire configuration\n");
445 goto err_free_irq;
446 }
447 titsc_step_config(ts_dev);
448 titsc_writel(ts_dev, REG_FIFO0THR,
449 ts_dev->coordinate_readouts * 2 + 2 - 1);
450
451 input_dev->name = "ti-tsc";
452 input_dev->dev.parent = &pdev->dev;
453
454 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
455 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
456
457 input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
458 input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
459 input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
460
461 /* register to the input system */
462 err = input_register_device(input_dev);
463 if (err)
464 goto err_free_irq;
465
466 platform_set_drvdata(pdev, ts_dev);
467 return 0;
468
469 err_free_irq:
470 free_irq(ts_dev->irq, ts_dev);
471 err_free_mem:
472 input_free_device(input_dev);
473 kfree(ts_dev);
474 return err;
475 }
476
477 static int titsc_remove(struct platform_device *pdev)
478 {
479 struct titsc *ts_dev = platform_get_drvdata(pdev);
480 u32 steps;
481
482 free_irq(ts_dev->irq, ts_dev);
483
484 /* total steps followed by the enable mask */
485 steps = 2 * ts_dev->coordinate_readouts + 2;
486 steps = (1 << steps) - 1;
487 am335x_tsc_se_clr(ts_dev->mfd_tscadc, steps);
488
489 input_unregister_device(ts_dev->input);
490
491 kfree(ts_dev);
492 return 0;
493 }
494
495 static int __maybe_unused titsc_suspend(struct device *dev)
496 {
497 struct titsc *ts_dev = dev_get_drvdata(dev);
498 struct ti_tscadc_dev *tscadc_dev;
499 unsigned int idle;
500
501 tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
502 if (device_may_wakeup(tscadc_dev->dev)) {
503 titsc_writel(ts_dev, REG_IRQSTATUS, TSC_IRQENB_MASK);
504 idle = titsc_readl(ts_dev, REG_IRQENABLE);
505 titsc_writel(ts_dev, REG_IRQENABLE,
506 (idle | IRQENB_HW_PEN));
507 titsc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB);
508 }
509 return 0;
510 }
511
512 static int __maybe_unused titsc_resume(struct device *dev)
513 {
514 struct titsc *ts_dev = dev_get_drvdata(dev);
515 struct ti_tscadc_dev *tscadc_dev;
516
517 tscadc_dev = ti_tscadc_dev_get(to_platform_device(dev));
518 if (device_may_wakeup(tscadc_dev->dev)) {
519 titsc_writel(ts_dev, REG_IRQWAKEUP,
520 0x00);
521 titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
522 pm_relax(ts_dev->mfd_tscadc->dev);
523 }
524 titsc_step_config(ts_dev);
525 titsc_writel(ts_dev, REG_FIFO0THR,
526 ts_dev->coordinate_readouts * 2 + 2 - 1);
527 return 0;
528 }
529
530 static SIMPLE_DEV_PM_OPS(titsc_pm_ops, titsc_suspend, titsc_resume);
531
532 static const struct of_device_id ti_tsc_dt_ids[] = {
533 { .compatible = "ti,am3359-tsc", },
534 { }
535 };
536 MODULE_DEVICE_TABLE(of, ti_tsc_dt_ids);
537
538 static struct platform_driver ti_tsc_driver = {
539 .probe = titsc_probe,
540 .remove = titsc_remove,
541 .driver = {
542 .name = "TI-am335x-tsc",
543 .pm = &titsc_pm_ops,
544 .of_match_table = ti_tsc_dt_ids,
545 },
546 };
547 module_platform_driver(ti_tsc_driver);
548
549 MODULE_DESCRIPTION("TI touchscreen controller driver");
550 MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
551 MODULE_LICENSE("GPL");
Linux with added FPC-III support