xref: /openbmc/qemu/hw/input/tsc2005.c (revision 6016b7b4)
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 "qemu/osdep.h"
22 #include "qemu/log.h"
23 #include "qemu/timer.h"
24 #include "sysemu/reset.h"
25 #include "ui/console.h"
26 #include "hw/input/tsc2xxx.h"
27 #include "hw/irq.h"
28 #include "migration/vmstate.h"
29 #include "trace.h"
30 
31 #define TSC_CUT_RESOLUTION(value, p)	((value) >> (16 - (p ? 12 : 10)))
32 
33 typedef struct {
34     qemu_irq pint;	/* Combination of the nPENIRQ and DAV signals */
35     QEMUTimer *timer;
36     uint16_t model;
37 
38     int32_t x, y;
39     bool pressure;
40 
41     uint8_t reg, state;
42     bool irq, command;
43     uint16_t data, dav;
44 
45     bool busy;
46     bool enabled;
47     bool host_mode;
48     int8_t function;
49     int8_t nextfunction;
50     bool precision;
51     bool nextprecision;
52     uint16_t filter;
53     uint8_t pin_func;
54     uint16_t timing[2];
55     uint8_t noise;
56     bool reset;
57     bool pdst;
58     bool pnd0;
59     uint16_t temp_thr[2];
60     uint16_t aux_thr[2];
61 
62     int32_t tr[8];
63 } TSC2005State;
64 
65 enum {
66     TSC_MODE_XYZ_SCAN	= 0x0,
67     TSC_MODE_XY_SCAN,
68     TSC_MODE_X,
69     TSC_MODE_Y,
70     TSC_MODE_Z,
71     TSC_MODE_AUX,
72     TSC_MODE_TEMP1,
73     TSC_MODE_TEMP2,
74     TSC_MODE_AUX_SCAN,
75     TSC_MODE_X_TEST,
76     TSC_MODE_Y_TEST,
77     TSC_MODE_TS_TEST,
78     TSC_MODE_RESERVED,
79     TSC_MODE_XX_DRV,
80     TSC_MODE_YY_DRV,
81     TSC_MODE_YX_DRV,
82 };
83 
84 static const uint16_t mode_regs[16] = {
85     0xf000,	/* X, Y, Z scan */
86     0xc000,	/* X, Y scan */
87     0x8000,	/* X */
88     0x4000,	/* Y */
89     0x3000,	/* Z */
90     0x0800,	/* AUX */
91     0x0400,	/* TEMP1 */
92     0x0200,	/* TEMP2 */
93     0x0800,	/* AUX scan */
94     0x0040,	/* X test */
95     0x0020,	/* Y test */
96     0x0080,	/* Short-circuit test */
97     0x0000,	/* Reserved */
98     0x0000,	/* X+, X- drivers */
99     0x0000,	/* Y+, Y- drivers */
100     0x0000,	/* Y+, X- drivers */
101 };
102 
103 #define X_TRANSFORM(s)			\
104     ((s->y * s->tr[0] - s->x * s->tr[1]) / s->tr[2] + s->tr[3])
105 #define Y_TRANSFORM(s)			\
106     ((s->y * s->tr[4] - s->x * s->tr[5]) / s->tr[6] + s->tr[7])
107 #define Z1_TRANSFORM(s)			\
108     ((400 - ((s)->x >> 7) + ((s)->pressure << 10)) << 4)
109 #define Z2_TRANSFORM(s)			\
110     ((4000 + ((s)->y >> 7) - ((s)->pressure << 10)) << 4)
111 
112 #define AUX_VAL				(700 << 4)	/* +/- 3 at 12-bit */
113 #define TEMP1_VAL			(1264 << 4)	/* +/- 5 at 12-bit */
114 #define TEMP2_VAL			(1531 << 4)	/* +/- 5 at 12-bit */
115 
116 static uint16_t tsc2005_read(TSC2005State *s, int reg)
117 {
118     uint16_t ret;
119 
120     switch (reg) {
121     case 0x0:	/* X */
122         s->dav &= ~mode_regs[TSC_MODE_X];
123         return TSC_CUT_RESOLUTION(X_TRANSFORM(s), s->precision) +
124                 (s->noise & 3);
125     case 0x1:	/* Y */
126         s->dav &= ~mode_regs[TSC_MODE_Y];
127         s->noise ++;
128         return TSC_CUT_RESOLUTION(Y_TRANSFORM(s), s->precision) ^
129                 (s->noise & 3);
130     case 0x2:	/* Z1 */
131         s->dav &= 0xdfff;
132         return TSC_CUT_RESOLUTION(Z1_TRANSFORM(s), s->precision) -
133                 (s->noise & 3);
134     case 0x3:	/* Z2 */
135         s->dav &= 0xefff;
136         return TSC_CUT_RESOLUTION(Z2_TRANSFORM(s), s->precision) |
137                 (s->noise & 3);
138 
139     case 0x4:	/* AUX */
140         s->dav &= ~mode_regs[TSC_MODE_AUX];
141         return TSC_CUT_RESOLUTION(AUX_VAL, s->precision);
142 
143     case 0x5:	/* TEMP1 */
144         s->dav &= ~mode_regs[TSC_MODE_TEMP1];
145         return TSC_CUT_RESOLUTION(TEMP1_VAL, s->precision) -
146                 (s->noise & 5);
147     case 0x6:	/* TEMP2 */
148         s->dav &= 0xdfff;
149         s->dav &= ~mode_regs[TSC_MODE_TEMP2];
150         return TSC_CUT_RESOLUTION(TEMP2_VAL, s->precision) ^
151                 (s->noise & 3);
152 
153     case 0x7:	/* Status */
154         ret = s->dav | (s->reset << 7) | (s->pdst << 2) | 0x0;
155         s->dav &= ~(mode_regs[TSC_MODE_X_TEST] | mode_regs[TSC_MODE_Y_TEST] |
156                         mode_regs[TSC_MODE_TS_TEST]);
157         s->reset = true;
158         return ret;
159 
160     case 0x8:	/* AUX high treshold */
161         return s->aux_thr[1];
162     case 0x9:	/* AUX low treshold */
163         return s->aux_thr[0];
164 
165     case 0xa:	/* TEMP high treshold */
166         return s->temp_thr[1];
167     case 0xb:	/* TEMP low treshold */
168         return s->temp_thr[0];
169 
170     case 0xc:	/* CFR0 */
171         return (s->pressure << 15) | ((!s->busy) << 14) |
172                 (s->nextprecision << 13) | s->timing[0];
173     case 0xd:	/* CFR1 */
174         return s->timing[1];
175     case 0xe:	/* CFR2 */
176         return (s->pin_func << 14) | s->filter;
177 
178     case 0xf:	/* Function select status */
179         return s->function >= 0 ? 1 << s->function : 0;
180     }
181 
182     /* Never gets here */
183     return 0xffff;
184 }
185 
186 static void tsc2005_write(TSC2005State *s, int reg, uint16_t data)
187 {
188     switch (reg) {
189     case 0x8:	/* AUX high treshold */
190         s->aux_thr[1] = data;
191         break;
192     case 0x9:	/* AUX low treshold */
193         s->aux_thr[0] = data;
194         break;
195 
196     case 0xa:	/* TEMP high treshold */
197         s->temp_thr[1] = data;
198         break;
199     case 0xb:	/* TEMP low treshold */
200         s->temp_thr[0] = data;
201         break;
202 
203     case 0xc:	/* CFR0 */
204         s->host_mode = (data >> 15) != 0;
205         if (s->enabled != !(data & 0x4000)) {
206             s->enabled = !(data & 0x4000);
207             trace_tsc2005_sense(s->enabled ? "enabled" : "disabled");
208             if (s->busy && !s->enabled)
209                 timer_del(s->timer);
210             s->busy = s->busy && s->enabled;
211         }
212         s->nextprecision = (data >> 13) & 1;
213         s->timing[0] = data & 0x1fff;
214         if ((s->timing[0] >> 11) == 3) {
215             qemu_log_mask(LOG_GUEST_ERROR,
216                           "tsc2005_write: illegal conversion clock setting\n");
217         }
218         break;
219     case 0xd:	/* CFR1 */
220         s->timing[1] = data & 0xf07;
221         break;
222     case 0xe:	/* CFR2 */
223         s->pin_func = (data >> 14) & 3;
224         s->filter = data & 0x3fff;
225         break;
226 
227     default:
228         qemu_log_mask(LOG_GUEST_ERROR,
229                       "%s: write into read-only register 0x%x\n",
230                       __func__, reg);
231     }
232 }
233 
234 /* This handles most of the chip's logic.  */
235 static void tsc2005_pin_update(TSC2005State *s)
236 {
237     int64_t expires;
238     bool pin_state;
239 
240     switch (s->pin_func) {
241     case 0:
242         pin_state = !s->pressure && !!s->dav;
243         break;
244     case 1:
245     case 3:
246     default:
247         pin_state = !s->dav;
248         break;
249     case 2:
250         pin_state = !s->pressure;
251     }
252 
253     if (pin_state != s->irq) {
254         s->irq = pin_state;
255         qemu_set_irq(s->pint, s->irq);
256     }
257 
258     switch (s->nextfunction) {
259     case TSC_MODE_XYZ_SCAN:
260     case TSC_MODE_XY_SCAN:
261         if (!s->host_mode && s->dav)
262             s->enabled = false;
263         if (!s->pressure)
264             return;
265         /* Fall through */
266     case TSC_MODE_AUX_SCAN:
267         break;
268 
269     case TSC_MODE_X:
270     case TSC_MODE_Y:
271     case TSC_MODE_Z:
272         if (!s->pressure)
273             return;
274         /* Fall through */
275     case TSC_MODE_AUX:
276     case TSC_MODE_TEMP1:
277     case TSC_MODE_TEMP2:
278     case TSC_MODE_X_TEST:
279     case TSC_MODE_Y_TEST:
280     case TSC_MODE_TS_TEST:
281         if (s->dav)
282             s->enabled = false;
283         break;
284 
285     case TSC_MODE_RESERVED:
286     case TSC_MODE_XX_DRV:
287     case TSC_MODE_YY_DRV:
288     case TSC_MODE_YX_DRV:
289     default:
290         return;
291     }
292 
293     if (!s->enabled || s->busy)
294         return;
295 
296     s->busy = true;
297     s->precision = s->nextprecision;
298     s->function = s->nextfunction;
299     s->pdst = !s->pnd0;	/* Synchronised on internal clock */
300     expires = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
301         (NANOSECONDS_PER_SECOND >> 7);
302     timer_mod(s->timer, expires);
303 }
304 
305 static void tsc2005_reset(TSC2005State *s)
306 {
307     s->state = 0;
308     s->pin_func = 0;
309     s->enabled = false;
310     s->busy = false;
311     s->nextprecision = false;
312     s->nextfunction = 0;
313     s->timing[0] = 0;
314     s->timing[1] = 0;
315     s->irq = false;
316     s->dav = 0;
317     s->reset = false;
318     s->pdst = true;
319     s->pnd0 = false;
320     s->function = -1;
321     s->temp_thr[0] = 0x000;
322     s->temp_thr[1] = 0xfff;
323     s->aux_thr[0] = 0x000;
324     s->aux_thr[1] = 0xfff;
325 
326     tsc2005_pin_update(s);
327 }
328 
329 static uint8_t tsc2005_txrx_word(void *opaque, uint8_t value)
330 {
331     TSC2005State *s = opaque;
332     uint32_t ret = 0;
333 
334     switch (s->state ++) {
335     case 0:
336         if (value & 0x80) {
337             /* Command */
338             if (value & (1 << 1))
339                 tsc2005_reset(s);
340             else {
341                 s->nextfunction = (value >> 3) & 0xf;
342                 s->nextprecision = (value >> 2) & 1;
343                 if (s->enabled != !(value & 1)) {
344                     s->enabled = !(value & 1);
345                     trace_tsc2005_sense(s->enabled ? "enabled" : "disabled");
346                     if (s->busy && !s->enabled)
347                         timer_del(s->timer);
348                     s->busy = s->busy && s->enabled;
349                 }
350                 tsc2005_pin_update(s);
351             }
352 
353             s->state = 0;
354         } else if (value) {
355             /* Data transfer */
356             s->reg = (value >> 3) & 0xf;
357             s->pnd0 = (value >> 1) & 1;
358             s->command = value & 1;
359 
360             if (s->command) {
361                 /* Read */
362                 s->data = tsc2005_read(s, s->reg);
363                 tsc2005_pin_update(s);
364             } else
365                 s->data = 0;
366         } else
367             s->state = 0;
368         break;
369 
370     case 1:
371         if (s->command)
372             ret = (s->data >> 8) & 0xff;
373         else
374             s->data |= value << 8;
375         break;
376 
377     case 2:
378         if (s->command)
379             ret = s->data & 0xff;
380         else {
381             s->data |= value;
382             tsc2005_write(s, s->reg, s->data);
383             tsc2005_pin_update(s);
384         }
385 
386         s->state = 0;
387         break;
388     }
389 
390     return ret;
391 }
392 
393 uint32_t tsc2005_txrx(void *opaque, uint32_t value, int len)
394 {
395     uint32_t ret = 0;
396 
397     len &= ~7;
398     while (len > 0) {
399         len -= 8;
400         ret |= tsc2005_txrx_word(opaque, (value >> len) & 0xff) << len;
401     }
402 
403     return ret;
404 }
405 
406 static void tsc2005_timer_tick(void *opaque)
407 {
408     TSC2005State *s = opaque;
409 
410     /* Timer ticked -- a set of conversions has been finished.  */
411 
412     if (!s->busy)
413         return;
414 
415     s->busy = false;
416     s->dav |= mode_regs[s->function];
417     s->function = -1;
418     tsc2005_pin_update(s);
419 }
420 
421 static void tsc2005_touchscreen_event(void *opaque,
422                 int x, int y, int z, int buttons_state)
423 {
424     TSC2005State *s = opaque;
425     int p = s->pressure;
426 
427     if (buttons_state) {
428         s->x = x;
429         s->y = y;
430     }
431     s->pressure = !!buttons_state;
432 
433     /*
434      * Note: We would get better responsiveness in the guest by
435      * signaling TS events immediately, but for now we simulate
436      * the first conversion delay for sake of correctness.
437      */
438     if (p != s->pressure)
439         tsc2005_pin_update(s);
440 }
441 
442 static int tsc2005_post_load(void *opaque, int version_id)
443 {
444     TSC2005State *s = (TSC2005State *) opaque;
445 
446     s->busy = timer_pending(s->timer);
447     tsc2005_pin_update(s);
448 
449     return 0;
450 }
451 
452 static const VMStateDescription vmstate_tsc2005 = {
453     .name = "tsc2005",
454     .version_id = 2,
455     .minimum_version_id = 2,
456     .post_load = tsc2005_post_load,
457     .fields      = (VMStateField []) {
458         VMSTATE_BOOL(pressure, TSC2005State),
459         VMSTATE_BOOL(irq, TSC2005State),
460         VMSTATE_BOOL(command, TSC2005State),
461         VMSTATE_BOOL(enabled, TSC2005State),
462         VMSTATE_BOOL(host_mode, TSC2005State),
463         VMSTATE_BOOL(reset, TSC2005State),
464         VMSTATE_BOOL(pdst, TSC2005State),
465         VMSTATE_BOOL(pnd0, TSC2005State),
466         VMSTATE_BOOL(precision, TSC2005State),
467         VMSTATE_BOOL(nextprecision, TSC2005State),
468         VMSTATE_UINT8(reg, TSC2005State),
469         VMSTATE_UINT8(state, TSC2005State),
470         VMSTATE_UINT16(data, TSC2005State),
471         VMSTATE_UINT16(dav, TSC2005State),
472         VMSTATE_UINT16(filter, TSC2005State),
473         VMSTATE_INT8(nextfunction, TSC2005State),
474         VMSTATE_INT8(function, TSC2005State),
475         VMSTATE_INT32(x, TSC2005State),
476         VMSTATE_INT32(y, TSC2005State),
477         VMSTATE_TIMER_PTR(timer, TSC2005State),
478         VMSTATE_UINT8(pin_func, TSC2005State),
479         VMSTATE_UINT16_ARRAY(timing, TSC2005State, 2),
480         VMSTATE_UINT8(noise, TSC2005State),
481         VMSTATE_UINT16_ARRAY(temp_thr, TSC2005State, 2),
482         VMSTATE_UINT16_ARRAY(aux_thr, TSC2005State, 2),
483         VMSTATE_INT32_ARRAY(tr, TSC2005State, 8),
484         VMSTATE_END_OF_LIST()
485     }
486 };
487 
488 void *tsc2005_init(qemu_irq pintdav)
489 {
490     TSC2005State *s;
491 
492     s = (TSC2005State *)
493             g_malloc0(sizeof(TSC2005State));
494     s->x = 400;
495     s->y = 240;
496     s->pressure = false;
497     s->precision = s->nextprecision = false;
498     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, tsc2005_timer_tick, s);
499     s->pint = pintdav;
500     s->model = 0x2005;
501 
502     s->tr[0] = 0;
503     s->tr[1] = 1;
504     s->tr[2] = 1;
505     s->tr[3] = 0;
506     s->tr[4] = 1;
507     s->tr[5] = 0;
508     s->tr[6] = 1;
509     s->tr[7] = 0;
510 
511     tsc2005_reset(s);
512 
513     qemu_add_mouse_event_handler(tsc2005_touchscreen_event, s, 1,
514                     "QEMU TSC2005-driven Touchscreen");
515 
516     qemu_register_reset((void *) tsc2005_reset, s);
517     vmstate_register(NULL, 0, &vmstate_tsc2005, s);
518 
519     return s;
520 }
521 
522 /*
523  * Use tslib generated calibration data to generate ADC input values
524  * from the touchscreen.  Assuming 12-bit precision was used during
525  * tslib calibration.
526  */
527 void tsc2005_set_transform(void *opaque, MouseTransformInfo *info)
528 {
529     TSC2005State *s = (TSC2005State *) opaque;
530 
531     /* This version assumes touchscreen X & Y axis are parallel or
532      * perpendicular to LCD's  X & Y axis in some way.  */
533     if (abs(info->a[0]) > abs(info->a[1])) {
534         s->tr[0] = 0;
535         s->tr[1] = -info->a[6] * info->x;
536         s->tr[2] = info->a[0];
537         s->tr[3] = -info->a[2] / info->a[0];
538         s->tr[4] = info->a[6] * info->y;
539         s->tr[5] = 0;
540         s->tr[6] = info->a[4];
541         s->tr[7] = -info->a[5] / info->a[4];
542     } else {
543         s->tr[0] = info->a[6] * info->y;
544         s->tr[1] = 0;
545         s->tr[2] = info->a[1];
546         s->tr[3] = -info->a[2] / info->a[1];
547         s->tr[4] = 0;
548         s->tr[5] = -info->a[6] * info->x;
549         s->tr[6] = info->a[3];
550         s->tr[7] = -info->a[5] / info->a[3];
551     }
552 
553     s->tr[0] >>= 11;
554     s->tr[1] >>= 11;
555     s->tr[3] <<= 4;
556     s->tr[4] >>= 11;
557     s->tr[5] >>= 11;
558     s->tr[7] <<= 4;
559 }
560