diff options
Diffstat (limited to 'drivers/input/touchscreen/wm9713.c')
-rw-r--r-- | drivers/input/touchscreen/wm9713.c | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/wm9713.c b/drivers/input/touchscreen/wm9713.c new file mode 100644 index 000000000000..01278bd7e65c --- /dev/null +++ b/drivers/input/touchscreen/wm9713.c | |||
@@ -0,0 +1,460 @@ | |||
1 | /* | ||
2 | * wm9713.c -- Codec touch driver for Wolfson WM9713 AC97 Codec. | ||
3 | * | ||
4 | * Copyright 2003, 2004, 2005, 2006, 2007, 2008 Wolfson Microelectronics PLC. | ||
5 | * Author: Liam Girdwood | ||
6 | * liam.girdwood@wolfsonmicro.com or linux@wolfsonmicro.com | ||
7 | * Parts Copyright : Ian Molton <spyro@f2s.com> | ||
8 | * Andrew Zabolotny <zap@homelink.ru> | ||
9 | * Russell King <rmk@arm.linux.org.uk> | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or modify it | ||
12 | * under the terms of the GNU General Public License as published by the | ||
13 | * Free Software Foundation; either version 2 of the License, or (at your | ||
14 | * option) any later version. | ||
15 | * | ||
16 | */ | ||
17 | |||
18 | #include <linux/module.h> | ||
19 | #include <linux/moduleparam.h> | ||
20 | #include <linux/version.h> | ||
21 | #include <linux/kernel.h> | ||
22 | #include <linux/input.h> | ||
23 | #include <linux/delay.h> | ||
24 | #include <linux/bitops.h> | ||
25 | #include <linux/wm97xx.h> | ||
26 | |||
27 | #define TS_NAME "wm97xx" | ||
28 | #define WM9713_VERSION "1.00" | ||
29 | #define DEFAULT_PRESSURE 0xb0c0 | ||
30 | |||
31 | /* | ||
32 | * Module parameters | ||
33 | */ | ||
34 | |||
35 | /* | ||
36 | * Set internal pull up for pen detect. | ||
37 | * | ||
38 | * Pull up is in the range 1.02k (least sensitive) to 64k (most sensitive) | ||
39 | * i.e. pull up resistance = 64k Ohms / rpu. | ||
40 | * | ||
41 | * Adjust this value if you are having problems with pen detect not | ||
42 | * detecting any down event. | ||
43 | */ | ||
44 | static int rpu = 8; | ||
45 | module_param(rpu, int, 0); | ||
46 | MODULE_PARM_DESC(rpu, "Set internal pull up resitor for pen detect."); | ||
47 | |||
48 | /* | ||
49 | * Set current used for pressure measurement. | ||
50 | * | ||
51 | * Set pil = 2 to use 400uA | ||
52 | * pil = 1 to use 200uA and | ||
53 | * pil = 0 to disable pressure measurement. | ||
54 | * | ||
55 | * This is used to increase the range of values returned by the adc | ||
56 | * when measureing touchpanel pressure. | ||
57 | */ | ||
58 | static int pil; | ||
59 | module_param(pil, int, 0); | ||
60 | MODULE_PARM_DESC(pil, "Set current used for pressure measurement."); | ||
61 | |||
62 | /* | ||
63 | * Set threshold for pressure measurement. | ||
64 | * | ||
65 | * Pen down pressure below threshold is ignored. | ||
66 | */ | ||
67 | static int pressure = DEFAULT_PRESSURE & 0xfff; | ||
68 | module_param(pressure, int, 0); | ||
69 | MODULE_PARM_DESC(pressure, "Set threshold for pressure measurement."); | ||
70 | |||
71 | /* | ||
72 | * Set adc sample delay. | ||
73 | * | ||
74 | * For accurate touchpanel measurements, some settling time may be | ||
75 | * required between the switch matrix applying a voltage across the | ||
76 | * touchpanel plate and the ADC sampling the signal. | ||
77 | * | ||
78 | * This delay can be set by setting delay = n, where n is the array | ||
79 | * position of the delay in the array delay_table below. | ||
80 | * Long delays > 1ms are supported for completeness, but are not | ||
81 | * recommended. | ||
82 | */ | ||
83 | static int delay = 4; | ||
84 | module_param(delay, int, 0); | ||
85 | MODULE_PARM_DESC(delay, "Set adc sample delay."); | ||
86 | |||
87 | /* | ||
88 | * Set adc mask function. | ||
89 | * | ||
90 | * Sources of glitch noise, such as signals driving an LCD display, may feed | ||
91 | * through to the touch screen plates and affect measurement accuracy. In | ||
92 | * order to minimise this, a signal may be applied to the MASK pin to delay or | ||
93 | * synchronise the sampling. | ||
94 | * | ||
95 | * 0 = No delay or sync | ||
96 | * 1 = High on pin stops conversions | ||
97 | * 2 = Edge triggered, edge on pin delays conversion by delay param (above) | ||
98 | * 3 = Edge triggered, edge on pin starts conversion after delay param | ||
99 | */ | ||
100 | static int mask; | ||
101 | module_param(mask, int, 0); | ||
102 | MODULE_PARM_DESC(mask, "Set adc mask function."); | ||
103 | |||
104 | /* | ||
105 | * Coordinate Polling Enable. | ||
106 | * | ||
107 | * Set to 1 to enable coordinate polling. e.g. x,y[,p] is sampled together | ||
108 | * for every poll. | ||
109 | */ | ||
110 | static int coord; | ||
111 | module_param(coord, int, 0); | ||
112 | MODULE_PARM_DESC(coord, "Polling coordinate mode"); | ||
113 | |||
114 | /* | ||
115 | * ADC sample delay times in uS | ||
116 | */ | ||
117 | static const int delay_table[] = { | ||
118 | 21, /* 1 AC97 Link frames */ | ||
119 | 42, /* 2 */ | ||
120 | 84, /* 4 */ | ||
121 | 167, /* 8 */ | ||
122 | 333, /* 16 */ | ||
123 | 667, /* 32 */ | ||
124 | 1000, /* 48 */ | ||
125 | 1333, /* 64 */ | ||
126 | 2000, /* 96 */ | ||
127 | 2667, /* 128 */ | ||
128 | 3333, /* 160 */ | ||
129 | 4000, /* 192 */ | ||
130 | 4667, /* 224 */ | ||
131 | 5333, /* 256 */ | ||
132 | 6000, /* 288 */ | ||
133 | 0 /* No delay, switch matrix always on */ | ||
134 | }; | ||
135 | |||
136 | /* | ||
137 | * Delay after issuing a POLL command. | ||
138 | * | ||
139 | * The delay is 3 AC97 link frames + the touchpanel settling delay | ||
140 | */ | ||
141 | static inline void poll_delay(int d) | ||
142 | { | ||
143 | udelay(3 * AC97_LINK_FRAME + delay_table[d]); | ||
144 | } | ||
145 | |||
146 | /* | ||
147 | * set up the physical settings of the WM9713 | ||
148 | */ | ||
149 | static void wm9713_phy_init(struct wm97xx *wm) | ||
150 | { | ||
151 | u16 dig1 = 0, dig2, dig3; | ||
152 | |||
153 | /* default values */ | ||
154 | dig2 = WM97XX_DELAY(4) | WM97XX_SLT(5); | ||
155 | dig3 = WM9712_RPU(1); | ||
156 | |||
157 | /* rpu */ | ||
158 | if (rpu) { | ||
159 | dig3 &= 0xffc0; | ||
160 | dig3 |= WM9712_RPU(rpu); | ||
161 | dev_info(wm->dev, "setting pen detect pull-up to %d Ohms\n", | ||
162 | 64000 / rpu); | ||
163 | } | ||
164 | |||
165 | /* touchpanel pressure */ | ||
166 | if (pil == 2) { | ||
167 | dig3 |= WM9712_PIL; | ||
168 | dev_info(wm->dev, | ||
169 | "setting pressure measurement current to 400uA."); | ||
170 | } else if (pil) | ||
171 | dev_info(wm->dev, | ||
172 | "setting pressure measurement current to 200uA."); | ||
173 | if (!pil) | ||
174 | pressure = 0; | ||
175 | |||
176 | /* sample settling delay */ | ||
177 | if (delay < 0 || delay > 15) { | ||
178 | dev_info(wm->dev, "supplied delay out of range."); | ||
179 | delay = 4; | ||
180 | dev_info(wm->dev, "setting adc sample delay to %d u Secs.", | ||
181 | delay_table[delay]); | ||
182 | } | ||
183 | dig2 &= 0xff0f; | ||
184 | dig2 |= WM97XX_DELAY(delay); | ||
185 | |||
186 | /* mask */ | ||
187 | dig3 |= ((mask & 0x3) << 4); | ||
188 | if (coord) | ||
189 | dig3 |= WM9713_WAIT; | ||
190 | |||
191 | wm->misc = wm97xx_reg_read(wm, 0x5a); | ||
192 | |||
193 | wm97xx_reg_write(wm, AC97_WM9713_DIG1, dig1); | ||
194 | wm97xx_reg_write(wm, AC97_WM9713_DIG2, dig2); | ||
195 | wm97xx_reg_write(wm, AC97_WM9713_DIG3, dig3); | ||
196 | wm97xx_reg_write(wm, AC97_GPIO_STICKY, 0x0); | ||
197 | } | ||
198 | |||
199 | static void wm9713_dig_enable(struct wm97xx *wm, int enable) | ||
200 | { | ||
201 | u16 val; | ||
202 | |||
203 | if (enable) { | ||
204 | val = wm97xx_reg_read(wm, AC97_EXTENDED_MID); | ||
205 | wm97xx_reg_write(wm, AC97_EXTENDED_MID, val & 0x7fff); | ||
206 | wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2] | | ||
207 | WM97XX_PRP_DET_DIG); | ||
208 | wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */ | ||
209 | } else { | ||
210 | wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2] & | ||
211 | ~WM97XX_PRP_DET_DIG); | ||
212 | val = wm97xx_reg_read(wm, AC97_EXTENDED_MID); | ||
213 | wm97xx_reg_write(wm, AC97_EXTENDED_MID, val | 0x8000); | ||
214 | } | ||
215 | } | ||
216 | |||
217 | static void wm9713_dig_restore(struct wm97xx *wm) | ||
218 | { | ||
219 | wm97xx_reg_write(wm, AC97_WM9713_DIG1, wm->dig_save[0]); | ||
220 | wm97xx_reg_write(wm, AC97_WM9713_DIG2, wm->dig_save[1]); | ||
221 | wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig_save[2]); | ||
222 | } | ||
223 | |||
224 | static void wm9713_aux_prepare(struct wm97xx *wm) | ||
225 | { | ||
226 | memcpy(wm->dig_save, wm->dig, sizeof(wm->dig)); | ||
227 | wm97xx_reg_write(wm, AC97_WM9713_DIG1, 0); | ||
228 | wm97xx_reg_write(wm, AC97_WM9713_DIG2, 0); | ||
229 | wm97xx_reg_write(wm, AC97_WM9713_DIG3, WM97XX_PRP_DET_DIG); | ||
230 | } | ||
231 | |||
232 | static inline int is_pden(struct wm97xx *wm) | ||
233 | { | ||
234 | return wm->dig[2] & WM9713_PDEN; | ||
235 | } | ||
236 | |||
237 | /* | ||
238 | * Read a sample from the WM9713 adc in polling mode. | ||
239 | */ | ||
240 | static int wm9713_poll_sample(struct wm97xx *wm, int adcsel, int *sample) | ||
241 | { | ||
242 | u16 dig1; | ||
243 | int timeout = 5 * delay; | ||
244 | |||
245 | if (!wm->pen_probably_down) { | ||
246 | u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); | ||
247 | if (!(data & WM97XX_PEN_DOWN)) | ||
248 | return RC_PENUP; | ||
249 | wm->pen_probably_down = 1; | ||
250 | } | ||
251 | |||
252 | /* set up digitiser */ | ||
253 | if (adcsel & 0x8000) | ||
254 | adcsel = 1 << ((adcsel & 0x7fff) + 3); | ||
255 | |||
256 | dig1 = wm97xx_reg_read(wm, AC97_WM9713_DIG1); | ||
257 | dig1 &= ~WM9713_ADCSEL_MASK; | ||
258 | |||
259 | if (wm->mach_ops && wm->mach_ops->pre_sample) | ||
260 | wm->mach_ops->pre_sample(adcsel); | ||
261 | wm97xx_reg_write(wm, AC97_WM9713_DIG1, dig1 | adcsel | WM9713_POLL); | ||
262 | |||
263 | /* wait 3 AC97 time slots + delay for conversion */ | ||
264 | poll_delay(delay); | ||
265 | |||
266 | /* wait for POLL to go low */ | ||
267 | while ((wm97xx_reg_read(wm, AC97_WM9713_DIG1) & WM9713_POLL) && | ||
268 | timeout) { | ||
269 | udelay(AC97_LINK_FRAME); | ||
270 | timeout--; | ||
271 | } | ||
272 | |||
273 | if (timeout <= 0) { | ||
274 | /* If PDEN is set, we can get a timeout when pen goes up */ | ||
275 | if (is_pden(wm)) | ||
276 | wm->pen_probably_down = 0; | ||
277 | else | ||
278 | dev_dbg(wm->dev, "adc sample timeout"); | ||
279 | return RC_PENUP; | ||
280 | } | ||
281 | |||
282 | *sample = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); | ||
283 | if (wm->mach_ops && wm->mach_ops->post_sample) | ||
284 | wm->mach_ops->post_sample(adcsel); | ||
285 | |||
286 | /* check we have correct sample */ | ||
287 | if ((*sample & WM97XX_ADCSRC_MASK) != ffs(adcsel >> 1) << 12) { | ||
288 | dev_dbg(wm->dev, "adc wrong sample, read %x got %x", adcsel, | ||
289 | *sample & WM97XX_ADCSRC_MASK); | ||
290 | return RC_PENUP; | ||
291 | } | ||
292 | |||
293 | if (!(*sample & WM97XX_PEN_DOWN)) { | ||
294 | wm->pen_probably_down = 0; | ||
295 | return RC_PENUP; | ||
296 | } | ||
297 | |||
298 | return RC_VALID; | ||
299 | } | ||
300 | |||
301 | /* | ||
302 | * Read a coordinate from the WM9713 adc in polling mode. | ||
303 | */ | ||
304 | static int wm9713_poll_coord(struct wm97xx *wm, struct wm97xx_data *data) | ||
305 | { | ||
306 | u16 dig1; | ||
307 | int timeout = 5 * delay; | ||
308 | |||
309 | if (!wm->pen_probably_down) { | ||
310 | u16 val = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); | ||
311 | if (!(val & WM97XX_PEN_DOWN)) | ||
312 | return RC_PENUP; | ||
313 | wm->pen_probably_down = 1; | ||
314 | } | ||
315 | |||
316 | /* set up digitiser */ | ||
317 | dig1 = wm97xx_reg_read(wm, AC97_WM9713_DIG1); | ||
318 | dig1 &= ~WM9713_ADCSEL_MASK; | ||
319 | if (pil) | ||
320 | dig1 |= WM9713_ADCSEL_PRES; | ||
321 | |||
322 | if (wm->mach_ops && wm->mach_ops->pre_sample) | ||
323 | wm->mach_ops->pre_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y); | ||
324 | wm97xx_reg_write(wm, AC97_WM9713_DIG1, | ||
325 | dig1 | WM9713_POLL | WM9713_COO); | ||
326 | |||
327 | /* wait 3 AC97 time slots + delay for conversion */ | ||
328 | poll_delay(delay); | ||
329 | data->x = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); | ||
330 | /* wait for POLL to go low */ | ||
331 | while ((wm97xx_reg_read(wm, AC97_WM9713_DIG1) & WM9713_POLL) | ||
332 | && timeout) { | ||
333 | udelay(AC97_LINK_FRAME); | ||
334 | timeout--; | ||
335 | } | ||
336 | |||
337 | if (timeout <= 0) { | ||
338 | /* If PDEN is set, we can get a timeout when pen goes up */ | ||
339 | if (is_pden(wm)) | ||
340 | wm->pen_probably_down = 0; | ||
341 | else | ||
342 | dev_dbg(wm->dev, "adc sample timeout"); | ||
343 | return RC_PENUP; | ||
344 | } | ||
345 | |||
346 | /* read back data */ | ||
347 | data->y = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); | ||
348 | if (pil) | ||
349 | data->p = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); | ||
350 | else | ||
351 | data->p = DEFAULT_PRESSURE; | ||
352 | |||
353 | if (wm->mach_ops && wm->mach_ops->post_sample) | ||
354 | wm->mach_ops->post_sample(WM97XX_ADCSEL_X | WM97XX_ADCSEL_Y); | ||
355 | |||
356 | /* check we have correct sample */ | ||
357 | if (!(data->x & WM97XX_ADCSEL_X) || !(data->y & WM97XX_ADCSEL_Y)) | ||
358 | goto err; | ||
359 | if (pil && !(data->p & WM97XX_ADCSEL_PRES)) | ||
360 | goto err; | ||
361 | |||
362 | if (!(data->x & WM97XX_PEN_DOWN) || !(data->y & WM97XX_PEN_DOWN)) { | ||
363 | wm->pen_probably_down = 0; | ||
364 | return RC_PENUP; | ||
365 | } | ||
366 | return RC_VALID; | ||
367 | err: | ||
368 | return 0; | ||
369 | } | ||
370 | |||
371 | /* | ||
372 | * Sample the WM9713 touchscreen in polling mode | ||
373 | */ | ||
374 | static int wm9713_poll_touch(struct wm97xx *wm, struct wm97xx_data *data) | ||
375 | { | ||
376 | int rc; | ||
377 | |||
378 | if (coord) { | ||
379 | rc = wm9713_poll_coord(wm, data); | ||
380 | if (rc != RC_VALID) | ||
381 | return rc; | ||
382 | } else { | ||
383 | rc = wm9713_poll_sample(wm, WM9713_ADCSEL_X, &data->x); | ||
384 | if (rc != RC_VALID) | ||
385 | return rc; | ||
386 | rc = wm9713_poll_sample(wm, WM9713_ADCSEL_Y, &data->y); | ||
387 | if (rc != RC_VALID) | ||
388 | return rc; | ||
389 | if (pil) { | ||
390 | rc = wm9713_poll_sample(wm, WM9713_ADCSEL_PRES, | ||
391 | &data->p); | ||
392 | if (rc != RC_VALID) | ||
393 | return rc; | ||
394 | } else | ||
395 | data->p = DEFAULT_PRESSURE; | ||
396 | } | ||
397 | return RC_VALID; | ||
398 | } | ||
399 | |||
400 | /* | ||
401 | * Enable WM9713 continuous mode, i.e. touch data is streamed across | ||
402 | * an AC97 slot | ||
403 | */ | ||
404 | static int wm9713_acc_enable(struct wm97xx *wm, int enable) | ||
405 | { | ||
406 | u16 dig1, dig2, dig3; | ||
407 | int ret = 0; | ||
408 | |||
409 | dig1 = wm->dig[0]; | ||
410 | dig2 = wm->dig[1]; | ||
411 | dig3 = wm->dig[2]; | ||
412 | |||
413 | if (enable) { | ||
414 | /* continous mode */ | ||
415 | if (wm->mach_ops->acc_startup && | ||
416 | (ret = wm->mach_ops->acc_startup(wm)) < 0) | ||
417 | return ret; | ||
418 | |||
419 | dig1 &= ~WM9713_ADCSEL_MASK; | ||
420 | dig1 |= WM9713_CTC | WM9713_COO | WM9713_ADCSEL_X | | ||
421 | WM9713_ADCSEL_Y; | ||
422 | if (pil) | ||
423 | dig1 |= WM9713_ADCSEL_PRES; | ||
424 | dig2 &= ~(WM97XX_DELAY_MASK | WM97XX_SLT_MASK | | ||
425 | WM97XX_CM_RATE_MASK); | ||
426 | dig2 |= WM97XX_SLEN | WM97XX_DELAY(delay) | | ||
427 | WM97XX_SLT(wm->acc_slot) | WM97XX_RATE(wm->acc_rate); | ||
428 | dig3 |= WM9713_PDEN; | ||
429 | } else { | ||
430 | dig1 &= ~(WM9713_CTC | WM9713_COO); | ||
431 | dig2 &= ~WM97XX_SLEN; | ||
432 | dig3 &= ~WM9713_PDEN; | ||
433 | if (wm->mach_ops->acc_shutdown) | ||
434 | wm->mach_ops->acc_shutdown(wm); | ||
435 | } | ||
436 | |||
437 | wm97xx_reg_write(wm, AC97_WM9713_DIG1, dig1); | ||
438 | wm97xx_reg_write(wm, AC97_WM9713_DIG2, dig2); | ||
439 | wm97xx_reg_write(wm, AC97_WM9713_DIG3, dig3); | ||
440 | |||
441 | return ret; | ||
442 | } | ||
443 | |||
444 | struct wm97xx_codec_drv wm9713_codec = { | ||
445 | .id = WM9713_ID2, | ||
446 | .name = "wm9713", | ||
447 | .poll_sample = wm9713_poll_sample, | ||
448 | .poll_touch = wm9713_poll_touch, | ||
449 | .acc_enable = wm9713_acc_enable, | ||
450 | .phy_init = wm9713_phy_init, | ||
451 | .dig_enable = wm9713_dig_enable, | ||
452 | .dig_restore = wm9713_dig_restore, | ||
453 | .aux_prepare = wm9713_aux_prepare, | ||
454 | }; | ||
455 | EXPORT_SYMBOL_GPL(wm9713_codec); | ||
456 | |||
457 | /* Module information */ | ||
458 | MODULE_AUTHOR("Liam Girdwood <liam.girdwood@wolfsonmicro.com>"); | ||
459 | MODULE_DESCRIPTION("WM9713 Touch Screen Driver"); | ||
460 | MODULE_LICENSE("GPL"); | ||