xref: /openbmc/qemu/hw/input/tsc2005.c (revision dccfcd0e)
1 /*
2  * TI TSC2005 emulator.
3  *
4  * Copyright (c) 2006 Andrzej Zaborowski  <balrog@zabor.org>
5  * Copyright (C) 2008 Nokia Corporation
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation; either version 2 or
10  * (at your option) version 3 of the License.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License along
18  * with this program; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "hw/hw.h"
22 #include "qemu/timer.h"
23 #include "ui/console.h"
24 #include "hw/devices.h"
25 
26 #define TSC_CUT_RESOLUTION(value, p)	((value) >> (16 - (p ? 12 : 10)))
27 
28 typedef struct {
29     qemu_irq pint;	/* Combination of the nPENIRQ and DAV signals */
30     QEMUTimer *timer;
31     uint16_t model;
32 
33     int x, y;
34     int pressure;
35 
36     int state, reg, irq, command;
37     uint16_t data, dav;
38 
39     int busy;
40     int enabled;
41     int host_mode;
42     int function;
43     int nextfunction;
44     int precision;
45     int nextprecision;
46     int filter;
47     int pin_func;
48     int timing[2];
49     int noise;
50     int reset;
51     int pdst;
52     int pnd0;
53     uint16_t temp_thr[2];
54     uint16_t aux_thr[2];
55 
56     int tr[8];
57 } TSC2005State;
58 
59 enum {
60     TSC_MODE_XYZ_SCAN	= 0x0,
61     TSC_MODE_XY_SCAN,
62     TSC_MODE_X,
63     TSC_MODE_Y,
64     TSC_MODE_Z,
65     TSC_MODE_AUX,
66     TSC_MODE_TEMP1,
67     TSC_MODE_TEMP2,
68     TSC_MODE_AUX_SCAN,
69     TSC_MODE_X_TEST,
70     TSC_MODE_Y_TEST,
71     TSC_MODE_TS_TEST,
72     TSC_MODE_RESERVED,
73     TSC_MODE_XX_DRV,
74     TSC_MODE_YY_DRV,
75     TSC_MODE_YX_DRV,
76 };
77 
78 static const uint16_t mode_regs[16] = {
79     0xf000,	/* X, Y, Z scan */
80     0xc000,	/* X, Y scan */
81     0x8000,	/* X */
82     0x4000,	/* Y */
83     0x3000,	/* Z */
84     0x0800,	/* AUX */
85     0x0400,	/* TEMP1 */
86     0x0200,	/* TEMP2 */
87     0x0800,	/* AUX scan */
88     0x0040,	/* X test */
89     0x0020,	/* Y test */
90     0x0080,	/* Short-circuit test */
91     0x0000,	/* Reserved */
92     0x0000,	/* X+, X- drivers */
93     0x0000,	/* Y+, Y- drivers */
94     0x0000,	/* Y+, X- drivers */
95 };
96 
97 #define X_TRANSFORM(s)			\
98     ((s->y * s->tr[0] - s->x * s->tr[1]) / s->tr[2] + s->tr[3])
99 #define Y_TRANSFORM(s)			\
100     ((s->y * s->tr[4] - s->x * s->tr[5]) / s->tr[6] + s->tr[7])
101 #define Z1_TRANSFORM(s)			\
102     ((400 - ((s)->x >> 7) + ((s)->pressure << 10)) << 4)
103 #define Z2_TRANSFORM(s)			\
104     ((4000 + ((s)->y >> 7) - ((s)->pressure << 10)) << 4)
105 
106 #define AUX_VAL				(700 << 4)	/* +/- 3 at 12-bit */
107 #define TEMP1_VAL			(1264 << 4)	/* +/- 5 at 12-bit */
108 #define TEMP2_VAL			(1531 << 4)	/* +/- 5 at 12-bit */
109 
110 static uint16_t tsc2005_read(TSC2005State *s, int reg)
111 {
112     uint16_t ret;
113 
114     switch (reg) {
115     case 0x0:	/* X */
116         s->dav &= ~mode_regs[TSC_MODE_X];
117         return TSC_CUT_RESOLUTION(X_TRANSFORM(s), s->precision) +
118                 (s->noise & 3);
119     case 0x1:	/* Y */
120         s->dav &= ~mode_regs[TSC_MODE_Y];
121         s->noise ++;
122         return TSC_CUT_RESOLUTION(Y_TRANSFORM(s), s->precision) ^
123                 (s->noise & 3);
124     case 0x2:	/* Z1 */
125         s->dav &= 0xdfff;
126         return TSC_CUT_RESOLUTION(Z1_TRANSFORM(s), s->precision) -
127                 (s->noise & 3);
128     case 0x3:	/* Z2 */
129         s->dav &= 0xefff;
130         return TSC_CUT_RESOLUTION(Z2_TRANSFORM(s), s->precision) |
131                 (s->noise & 3);
132 
133     case 0x4:	/* AUX */
134         s->dav &= ~mode_regs[TSC_MODE_AUX];
135         return TSC_CUT_RESOLUTION(AUX_VAL, s->precision);
136 
137     case 0x5:	/* TEMP1 */
138         s->dav &= ~mode_regs[TSC_MODE_TEMP1];
139         return TSC_CUT_RESOLUTION(TEMP1_VAL, s->precision) -
140                 (s->noise & 5);
141     case 0x6:	/* TEMP2 */
142         s->dav &= 0xdfff;
143         s->dav &= ~mode_regs[TSC_MODE_TEMP2];
144         return TSC_CUT_RESOLUTION(TEMP2_VAL, s->precision) ^
145                 (s->noise & 3);
146 
147     case 0x7:	/* Status */
148         ret = s->dav | (s->reset << 7) | (s->pdst << 2) | 0x0;
149         s->dav &= ~(mode_regs[TSC_MODE_X_TEST] | mode_regs[TSC_MODE_Y_TEST] |
150                         mode_regs[TSC_MODE_TS_TEST]);
151         s->reset = 1;
152         return ret;
153 
154     case 0x8:	/* AUX high treshold */
155         return s->aux_thr[1];
156     case 0x9:	/* AUX low treshold */
157         return s->aux_thr[0];
158 
159     case 0xa:	/* TEMP high treshold */
160         return s->temp_thr[1];
161     case 0xb:	/* TEMP low treshold */
162         return s->temp_thr[0];
163 
164     case 0xc:	/* CFR0 */
165         return (s->pressure << 15) | ((!s->busy) << 14) |
166                 (s->nextprecision << 13) | s->timing[0];
167     case 0xd:	/* CFR1 */
168         return s->timing[1];
169     case 0xe:	/* CFR2 */
170         return (s->pin_func << 14) | s->filter;
171 
172     case 0xf:	/* Function select status */
173         return s->function >= 0 ? 1 << s->function : 0;
174     }
175 
176     /* Never gets here */
177     return 0xffff;
178 }
179 
180 static void tsc2005_write(TSC2005State *s, int reg, uint16_t data)
181 {
182     switch (reg) {
183     case 0x8:	/* AUX high treshold */
184         s->aux_thr[1] = data;
185         break;
186     case 0x9:	/* AUX low treshold */
187         s->aux_thr[0] = data;
188         break;
189 
190     case 0xa:	/* TEMP high treshold */
191         s->temp_thr[1] = data;
192         break;
193     case 0xb:	/* TEMP low treshold */
194         s->temp_thr[0] = data;
195         break;
196 
197     case 0xc:	/* CFR0 */
198         s->host_mode = data >> 15;
199         if (s->enabled != !(data & 0x4000)) {
200             s->enabled = !(data & 0x4000);
201             fprintf(stderr, "%s: touchscreen sense %sabled\n",
202                             __FUNCTION__, s->enabled ? "en" : "dis");
203             if (s->busy && !s->enabled)
204                 qemu_del_timer(s->timer);
205             s->busy &= s->enabled;
206         }
207         s->nextprecision = (data >> 13) & 1;
208         s->timing[0] = data & 0x1fff;
209         if ((s->timing[0] >> 11) == 3)
210             fprintf(stderr, "%s: illegal conversion clock setting\n",
211                             __FUNCTION__);
212         break;
213     case 0xd:	/* CFR1 */
214         s->timing[1] = data & 0xf07;
215         break;
216     case 0xe:	/* CFR2 */
217         s->pin_func = (data >> 14) & 3;
218         s->filter = data & 0x3fff;
219         break;
220 
221     default:
222         fprintf(stderr, "%s: write into read-only register %x\n",
223                         __FUNCTION__, reg);
224     }
225 }
226 
227 /* This handles most of the chip's logic.  */
228 static void tsc2005_pin_update(TSC2005State *s)
229 {
230     int64_t expires;
231     int pin_state;
232 
233     switch (s->pin_func) {
234     case 0:
235         pin_state = !s->pressure && !!s->dav;
236         break;
237     case 1:
238     case 3:
239     default:
240         pin_state = !s->dav;
241         break;
242     case 2:
243         pin_state = !s->pressure;
244     }
245 
246     if (pin_state != s->irq) {
247         s->irq = pin_state;
248         qemu_set_irq(s->pint, s->irq);
249     }
250 
251     switch (s->nextfunction) {
252     case TSC_MODE_XYZ_SCAN:
253     case TSC_MODE_XY_SCAN:
254         if (!s->host_mode && s->dav)
255             s->enabled = 0;
256         if (!s->pressure)
257             return;
258         /* Fall through */
259     case TSC_MODE_AUX_SCAN:
260         break;
261 
262     case TSC_MODE_X:
263     case TSC_MODE_Y:
264     case TSC_MODE_Z:
265         if (!s->pressure)
266             return;
267         /* Fall through */
268     case TSC_MODE_AUX:
269     case TSC_MODE_TEMP1:
270     case TSC_MODE_TEMP2:
271     case TSC_MODE_X_TEST:
272     case TSC_MODE_Y_TEST:
273     case TSC_MODE_TS_TEST:
274         if (s->dav)
275             s->enabled = 0;
276         break;
277 
278     case TSC_MODE_RESERVED:
279     case TSC_MODE_XX_DRV:
280     case TSC_MODE_YY_DRV:
281     case TSC_MODE_YX_DRV:
282     default:
283         return;
284     }
285 
286     if (!s->enabled || s->busy)
287         return;
288 
289     s->busy = 1;
290     s->precision = s->nextprecision;
291     s->function = s->nextfunction;
292     s->pdst = !s->pnd0;	/* Synchronised on internal clock */
293     expires = qemu_get_clock_ns(vm_clock) + (get_ticks_per_sec() >> 7);
294     qemu_mod_timer(s->timer, expires);
295 }
296 
297 static void tsc2005_reset(TSC2005State *s)
298 {
299     s->state = 0;
300     s->pin_func = 0;
301     s->enabled = 0;
302     s->busy = 0;
303     s->nextprecision = 0;
304     s->nextfunction = 0;
305     s->timing[0] = 0;
306     s->timing[1] = 0;
307     s->irq = 0;
308     s->dav = 0;
309     s->reset = 0;
310     s->pdst = 1;
311     s->pnd0 = 0;
312     s->function = -1;
313     s->temp_thr[0] = 0x000;
314     s->temp_thr[1] = 0xfff;
315     s->aux_thr[0] = 0x000;
316     s->aux_thr[1] = 0xfff;
317 
318     tsc2005_pin_update(s);
319 }
320 
321 static uint8_t tsc2005_txrx_word(void *opaque, uint8_t value)
322 {
323     TSC2005State *s = opaque;
324     uint32_t ret = 0;
325 
326     switch (s->state ++) {
327     case 0:
328         if (value & 0x80) {
329             /* Command */
330             if (value & (1 << 1))
331                 tsc2005_reset(s);
332             else {
333                 s->nextfunction = (value >> 3) & 0xf;
334                 s->nextprecision = (value >> 2) & 1;
335                 if (s->enabled != !(value & 1)) {
336                     s->enabled = !(value & 1);
337                     fprintf(stderr, "%s: touchscreen sense %sabled\n",
338                                     __FUNCTION__, s->enabled ? "en" : "dis");
339                     if (s->busy && !s->enabled)
340                         qemu_del_timer(s->timer);
341                     s->busy &= s->enabled;
342                 }
343                 tsc2005_pin_update(s);
344             }
345 
346             s->state = 0;
347         } else if (value) {
348             /* Data transfer */
349             s->reg = (value >> 3) & 0xf;
350             s->pnd0 = (value >> 1) & 1;
351             s->command = value & 1;
352 
353             if (s->command) {
354                 /* Read */
355                 s->data = tsc2005_read(s, s->reg);
356                 tsc2005_pin_update(s);
357             } else
358                 s->data = 0;
359         } else
360             s->state = 0;
361         break;
362 
363     case 1:
364         if (s->command)
365             ret = (s->data >> 8) & 0xff;
366         else
367             s->data |= value << 8;
368         break;
369 
370     case 2:
371         if (s->command)
372             ret = s->data & 0xff;
373         else {
374             s->data |= value;
375             tsc2005_write(s, s->reg, s->data);
376             tsc2005_pin_update(s);
377         }
378 
379         s->state = 0;
380         break;
381     }
382 
383     return ret;
384 }
385 
386 uint32_t tsc2005_txrx(void *opaque, uint32_t value, int len)
387 {
388     uint32_t ret = 0;
389 
390     len &= ~7;
391     while (len > 0) {
392         len -= 8;
393         ret |= tsc2005_txrx_word(opaque, (value >> len) & 0xff) << len;
394     }
395 
396     return ret;
397 }
398 
399 static void tsc2005_timer_tick(void *opaque)
400 {
401     TSC2005State *s = opaque;
402 
403     /* Timer ticked -- a set of conversions has been finished.  */
404 
405     if (!s->busy)
406         return;
407 
408     s->busy = 0;
409     s->dav |= mode_regs[s->function];
410     s->function = -1;
411     tsc2005_pin_update(s);
412 }
413 
414 static void tsc2005_touchscreen_event(void *opaque,
415                 int x, int y, int z, int buttons_state)
416 {
417     TSC2005State *s = opaque;
418     int p = s->pressure;
419 
420     if (buttons_state) {
421         s->x = x;
422         s->y = y;
423     }
424     s->pressure = !!buttons_state;
425 
426     /*
427      * Note: We would get better responsiveness in the guest by
428      * signaling TS events immediately, but for now we simulate
429      * the first conversion delay for sake of correctness.
430      */
431     if (p != s->pressure)
432         tsc2005_pin_update(s);
433 }
434 
435 static void tsc2005_save(QEMUFile *f, void *opaque)
436 {
437     TSC2005State *s = (TSC2005State *) opaque;
438     int i;
439 
440     qemu_put_be16(f, s->x);
441     qemu_put_be16(f, s->y);
442     qemu_put_byte(f, s->pressure);
443 
444     qemu_put_byte(f, s->state);
445     qemu_put_byte(f, s->reg);
446     qemu_put_byte(f, s->command);
447 
448     qemu_put_byte(f, s->irq);
449     qemu_put_be16s(f, &s->dav);
450     qemu_put_be16s(f, &s->data);
451 
452     qemu_put_timer(f, s->timer);
453     qemu_put_byte(f, s->enabled);
454     qemu_put_byte(f, s->host_mode);
455     qemu_put_byte(f, s->function);
456     qemu_put_byte(f, s->nextfunction);
457     qemu_put_byte(f, s->precision);
458     qemu_put_byte(f, s->nextprecision);
459     qemu_put_be16(f, s->filter);
460     qemu_put_byte(f, s->pin_func);
461     qemu_put_be16(f, s->timing[0]);
462     qemu_put_be16(f, s->timing[1]);
463     qemu_put_be16s(f, &s->temp_thr[0]);
464     qemu_put_be16s(f, &s->temp_thr[1]);
465     qemu_put_be16s(f, &s->aux_thr[0]);
466     qemu_put_be16s(f, &s->aux_thr[1]);
467     qemu_put_be32(f, s->noise);
468     qemu_put_byte(f, s->reset);
469     qemu_put_byte(f, s->pdst);
470     qemu_put_byte(f, s->pnd0);
471 
472     for (i = 0; i < 8; i ++)
473         qemu_put_be32(f, s->tr[i]);
474 }
475 
476 static int tsc2005_load(QEMUFile *f, void *opaque, int version_id)
477 {
478     TSC2005State *s = (TSC2005State *) opaque;
479     int i;
480 
481     s->x = qemu_get_be16(f);
482     s->y = qemu_get_be16(f);
483     s->pressure = qemu_get_byte(f);
484 
485     s->state = qemu_get_byte(f);
486     s->reg = qemu_get_byte(f);
487     s->command = qemu_get_byte(f);
488 
489     s->irq = qemu_get_byte(f);
490     qemu_get_be16s(f, &s->dav);
491     qemu_get_be16s(f, &s->data);
492 
493     qemu_get_timer(f, s->timer);
494     s->enabled = qemu_get_byte(f);
495     s->host_mode = qemu_get_byte(f);
496     s->function = qemu_get_byte(f);
497     s->nextfunction = qemu_get_byte(f);
498     s->precision = qemu_get_byte(f);
499     s->nextprecision = qemu_get_byte(f);
500     s->filter = qemu_get_be16(f);
501     s->pin_func = qemu_get_byte(f);
502     s->timing[0] = qemu_get_be16(f);
503     s->timing[1] = qemu_get_be16(f);
504     qemu_get_be16s(f, &s->temp_thr[0]);
505     qemu_get_be16s(f, &s->temp_thr[1]);
506     qemu_get_be16s(f, &s->aux_thr[0]);
507     qemu_get_be16s(f, &s->aux_thr[1]);
508     s->noise = qemu_get_be32(f);
509     s->reset = qemu_get_byte(f);
510     s->pdst = qemu_get_byte(f);
511     s->pnd0 = qemu_get_byte(f);
512 
513     for (i = 0; i < 8; i ++)
514         s->tr[i] = qemu_get_be32(f);
515 
516     s->busy = qemu_timer_pending(s->timer);
517     tsc2005_pin_update(s);
518 
519     return 0;
520 }
521 
522 void *tsc2005_init(qemu_irq pintdav)
523 {
524     TSC2005State *s;
525 
526     s = (TSC2005State *)
527             g_malloc0(sizeof(TSC2005State));
528     s->x = 400;
529     s->y = 240;
530     s->pressure = 0;
531     s->precision = s->nextprecision = 0;
532     s->timer = qemu_new_timer_ns(vm_clock, tsc2005_timer_tick, s);
533     s->pint = pintdav;
534     s->model = 0x2005;
535 
536     s->tr[0] = 0;
537     s->tr[1] = 1;
538     s->tr[2] = 1;
539     s->tr[3] = 0;
540     s->tr[4] = 1;
541     s->tr[5] = 0;
542     s->tr[6] = 1;
543     s->tr[7] = 0;
544 
545     tsc2005_reset(s);
546 
547     qemu_add_mouse_event_handler(tsc2005_touchscreen_event, s, 1,
548                     "QEMU TSC2005-driven Touchscreen");
549 
550     qemu_register_reset((void *) tsc2005_reset, s);
551     register_savevm(NULL, "tsc2005", -1, 0, tsc2005_save, tsc2005_load, s);
552 
553     return s;
554 }
555 
556 /*
557  * Use tslib generated calibration data to generate ADC input values
558  * from the touchscreen.  Assuming 12-bit precision was used during
559  * tslib calibration.
560  */
561 void tsc2005_set_transform(void *opaque, MouseTransformInfo *info)
562 {
563     TSC2005State *s = (TSC2005State *) opaque;
564 
565     /* This version assumes touchscreen X & Y axis are parallel or
566      * perpendicular to LCD's  X & Y axis in some way.  */
567     if (abs(info->a[0]) > abs(info->a[1])) {
568         s->tr[0] = 0;
569         s->tr[1] = -info->a[6] * info->x;
570         s->tr[2] = info->a[0];
571         s->tr[3] = -info->a[2] / info->a[0];
572         s->tr[4] = info->a[6] * info->y;
573         s->tr[5] = 0;
574         s->tr[6] = info->a[4];
575         s->tr[7] = -info->a[5] / info->a[4];
576     } else {
577         s->tr[0] = info->a[6] * info->y;
578         s->tr[1] = 0;
579         s->tr[2] = info->a[1];
580         s->tr[3] = -info->a[2] / info->a[1];
581         s->tr[4] = 0;
582         s->tr[5] = -info->a[6] * info->x;
583         s->tr[6] = info->a[3];
584         s->tr[7] = -info->a[5] / info->a[3];
585     }
586 
587     s->tr[0] >>= 11;
588     s->tr[1] >>= 11;
589     s->tr[3] <<= 4;
590     s->tr[4] >>= 11;
591     s->tr[5] >>= 11;
592     s->tr[7] <<= 4;
593 }
594