xref: /openbmc/qemu/hw/input/tsc2005.c (revision 4f7b1ecb)
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 threshold */
161         return s->aux_thr[1];
162     case 0x9: /* AUX low threshold */
163         return s->aux_thr[0];
164 
165     case 0xa: /* TEMP high threshold */
166         return s->temp_thr[1];
167     case 0xb: /* TEMP low threshold */
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 threshold */
190         s->aux_thr[1] = data;
191         break;
192     case 0x9:   /* AUX low threshold */
193         s->aux_thr[0] = data;
194         break;
195 
196     case 0xa:   /* TEMP high threshold */
197         s->temp_thr[1] = data;
198         break;
199     case 0xb:   /* TEMP low threshold */
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             }
211             s->busy = s->busy && s->enabled;
212         }
213         s->nextprecision = (data >> 13) & 1;
214         s->timing[0] = data & 0x1fff;
215         if ((s->timing[0] >> 11) == 3) {
216             qemu_log_mask(LOG_GUEST_ERROR,
217                           "tsc2005_write: illegal conversion clock setting\n");
218         }
219         break;
220     case 0xd: /* CFR1 */
221         s->timing[1] = data & 0xf07;
222         break;
223     case 0xe: /* CFR2 */
224         s->pin_func = (data >> 14) & 3;
225         s->filter = data & 0x3fff;
226         break;
227 
228     default:
229         qemu_log_mask(LOG_GUEST_ERROR,
230                       "%s: write into read-only register 0x%x\n",
231                       __func__, reg);
232     }
233 }
234 
235 /* This handles most of the chip's logic.  */
236 static void tsc2005_pin_update(TSC2005State *s)
237 {
238     int64_t expires;
239     bool pin_state;
240 
241     switch (s->pin_func) {
242     case 0:
243         pin_state = !s->pressure && !!s->dav;
244         break;
245     case 1:
246     case 3:
247     default:
248         pin_state = !s->dav;
249         break;
250     case 2:
251         pin_state = !s->pressure;
252     }
253 
254     if (pin_state != s->irq) {
255         s->irq = pin_state;
256         qemu_set_irq(s->pint, s->irq);
257     }
258 
259     switch (s->nextfunction) {
260     case TSC_MODE_XYZ_SCAN:
261     case TSC_MODE_XY_SCAN:
262         if (!s->host_mode && s->dav) {
263             s->enabled = false;
264         }
265         if (!s->pressure) {
266             return;
267         }
268         /* Fall through */
269     case TSC_MODE_AUX_SCAN:
270         break;
271 
272     case TSC_MODE_X:
273     case TSC_MODE_Y:
274     case TSC_MODE_Z:
275         if (!s->pressure) {
276             return;
277         }
278         /* Fall through */
279     case TSC_MODE_AUX:
280     case TSC_MODE_TEMP1:
281     case TSC_MODE_TEMP2:
282     case TSC_MODE_X_TEST:
283     case TSC_MODE_Y_TEST:
284     case TSC_MODE_TS_TEST:
285         if (s->dav) {
286             s->enabled = false;
287         }
288         break;
289 
290     case TSC_MODE_RESERVED:
291     case TSC_MODE_XX_DRV:
292     case TSC_MODE_YY_DRV:
293     case TSC_MODE_YX_DRV:
294     default:
295         return;
296     }
297 
298     if (!s->enabled || s->busy) {
299         return;
300     }
301 
302     s->busy = true;
303     s->precision = s->nextprecision;
304     s->function = s->nextfunction;
305     s->pdst = !s->pnd0; /* Synchronised on internal clock */
306     expires = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
307         (NANOSECONDS_PER_SECOND >> 7);
308     timer_mod(s->timer, expires);
309 }
310 
311 static void tsc2005_reset(TSC2005State *s)
312 {
313     s->state = 0;
314     s->pin_func = 0;
315     s->enabled = false;
316     s->busy = false;
317     s->nextprecision = false;
318     s->nextfunction = 0;
319     s->timing[0] = 0;
320     s->timing[1] = 0;
321     s->irq = false;
322     s->dav = 0;
323     s->reset = false;
324     s->pdst = true;
325     s->pnd0 = false;
326     s->function = -1;
327     s->temp_thr[0] = 0x000;
328     s->temp_thr[1] = 0xfff;
329     s->aux_thr[0] = 0x000;
330     s->aux_thr[1] = 0xfff;
331 
332     tsc2005_pin_update(s);
333 }
334 
335 static uint8_t tsc2005_txrx_word(void *opaque, uint8_t value)
336 {
337     TSC2005State *s = opaque;
338     uint32_t ret = 0;
339 
340     switch (s->state++) {
341     case 0:
342         if (value & 0x80) {
343             /* Command */
344             if (value & (1 << 1))
345                 tsc2005_reset(s);
346             else {
347                 s->nextfunction = (value >> 3) & 0xf;
348                 s->nextprecision = (value >> 2) & 1;
349                 if (s->enabled != !(value & 1)) {
350                     s->enabled = !(value & 1);
351                     trace_tsc2005_sense(s->enabled ? "enabled" : "disabled");
352                     if (s->busy && !s->enabled) {
353                         timer_del(s->timer);
354                     }
355                     s->busy = s->busy && s->enabled;
356                 }
357                 tsc2005_pin_update(s);
358             }
359 
360             s->state = 0;
361         } else if (value) {
362             /* Data transfer */
363             s->reg = (value >> 3) & 0xf;
364             s->pnd0 = (value >> 1) & 1;
365             s->command = value & 1;
366 
367             if (s->command) {
368                 /* Read */
369                 s->data = tsc2005_read(s, s->reg);
370                 tsc2005_pin_update(s);
371             } else
372                 s->data = 0;
373         } else
374             s->state = 0;
375         break;
376 
377     case 1:
378         if (s->command) {
379             ret = (s->data >> 8) & 0xff;
380         } else {
381             s->data |= value << 8;
382         }
383         break;
384 
385     case 2:
386         if (s->command)
387             ret = s->data & 0xff;
388         else {
389             s->data |= value;
390             tsc2005_write(s, s->reg, s->data);
391             tsc2005_pin_update(s);
392         }
393 
394         s->state = 0;
395         break;
396     }
397 
398     return ret;
399 }
400 
401 uint32_t tsc2005_txrx(void *opaque, uint32_t value, int len)
402 {
403     uint32_t ret = 0;
404 
405     len &= ~7;
406     while (len > 0) {
407         len -= 8;
408         ret |= tsc2005_txrx_word(opaque, (value >> len) & 0xff) << len;
409     }
410 
411     return ret;
412 }
413 
414 static void tsc2005_timer_tick(void *opaque)
415 {
416     TSC2005State *s = opaque;
417     unsigned int function = s->function;
418 
419     assert(function < ARRAY_SIZE(mode_regs));
420 
421     /* Timer ticked -- a set of conversions has been finished.  */
422 
423     if (!s->busy) {
424         return;
425     }
426 
427     s->busy = false;
428     s->dav |= mode_regs[function];
429     s->function = -1;
430     tsc2005_pin_update(s);
431 }
432 
433 static void tsc2005_touchscreen_event(void *opaque,
434                 int x, int y, int z, int buttons_state)
435 {
436     TSC2005State *s = opaque;
437     int p = s->pressure;
438 
439     if (buttons_state) {
440         s->x = x;
441         s->y = y;
442     }
443     s->pressure = !!buttons_state;
444 
445     /*
446      * Note: We would get better responsiveness in the guest by
447      * signaling TS events immediately, but for now we simulate
448      * the first conversion delay for sake of correctness.
449      */
450     if (p != s->pressure) {
451         tsc2005_pin_update(s);
452     }
453 }
454 
455 static int tsc2005_post_load(void *opaque, int version_id)
456 {
457     TSC2005State *s = (TSC2005State *) opaque;
458 
459     s->busy = timer_pending(s->timer);
460     tsc2005_pin_update(s);
461 
462     return 0;
463 }
464 
465 static const VMStateDescription vmstate_tsc2005 = {
466     .name = "tsc2005",
467     .version_id = 2,
468     .minimum_version_id = 2,
469     .post_load = tsc2005_post_load,
470     .fields = (const VMStateField []) {
471         VMSTATE_BOOL(pressure, TSC2005State),
472         VMSTATE_BOOL(irq, TSC2005State),
473         VMSTATE_BOOL(command, TSC2005State),
474         VMSTATE_BOOL(enabled, TSC2005State),
475         VMSTATE_BOOL(host_mode, TSC2005State),
476         VMSTATE_BOOL(reset, TSC2005State),
477         VMSTATE_BOOL(pdst, TSC2005State),
478         VMSTATE_BOOL(pnd0, TSC2005State),
479         VMSTATE_BOOL(precision, TSC2005State),
480         VMSTATE_BOOL(nextprecision, TSC2005State),
481         VMSTATE_UINT8(reg, TSC2005State),
482         VMSTATE_UINT8(state, TSC2005State),
483         VMSTATE_UINT16(data, TSC2005State),
484         VMSTATE_UINT16(dav, TSC2005State),
485         VMSTATE_UINT16(filter, TSC2005State),
486         VMSTATE_INT8(nextfunction, TSC2005State),
487         VMSTATE_INT8(function, TSC2005State),
488         VMSTATE_INT32(x, TSC2005State),
489         VMSTATE_INT32(y, TSC2005State),
490         VMSTATE_TIMER_PTR(timer, TSC2005State),
491         VMSTATE_UINT8(pin_func, TSC2005State),
492         VMSTATE_UINT16_ARRAY(timing, TSC2005State, 2),
493         VMSTATE_UINT8(noise, TSC2005State),
494         VMSTATE_UINT16_ARRAY(temp_thr, TSC2005State, 2),
495         VMSTATE_UINT16_ARRAY(aux_thr, TSC2005State, 2),
496         VMSTATE_INT32_ARRAY(tr, TSC2005State, 8),
497         VMSTATE_END_OF_LIST()
498     }
499 };
500 
501 void *tsc2005_init(qemu_irq pintdav)
502 {
503     TSC2005State *s;
504 
505     s = g_new0(TSC2005State, 1);
506     s->x = 400;
507     s->y = 240;
508     s->pressure = false;
509     s->precision = s->nextprecision = false;
510     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, tsc2005_timer_tick, s);
511     s->pint = pintdav;
512     s->model = 0x2005;
513 
514     s->tr[0] = 0;
515     s->tr[1] = 1;
516     s->tr[2] = 1;
517     s->tr[3] = 0;
518     s->tr[4] = 1;
519     s->tr[5] = 0;
520     s->tr[6] = 1;
521     s->tr[7] = 0;
522 
523     tsc2005_reset(s);
524 
525     qemu_add_mouse_event_handler(tsc2005_touchscreen_event, s, 1,
526                     "QEMU TSC2005-driven Touchscreen");
527 
528     qemu_register_reset((void *) tsc2005_reset, s);
529     vmstate_register(NULL, 0, &vmstate_tsc2005, s);
530 
531     return s;
532 }
533 
534 /*
535  * Use tslib generated calibration data to generate ADC input values
536  * from the touchscreen.  Assuming 12-bit precision was used during
537  * tslib calibration.
538  */
539 void tsc2005_set_transform(void *opaque, const MouseTransformInfo *info)
540 {
541     TSC2005State *s = (TSC2005State *) opaque;
542 
543     /* This version assumes touchscreen X & Y axis are parallel or
544      * perpendicular to LCD's  X & Y axis in some way.  */
545     if (abs(info->a[0]) > abs(info->a[1])) {
546         s->tr[0] = 0;
547         s->tr[1] = -info->a[6] * info->x;
548         s->tr[2] = info->a[0];
549         s->tr[3] = -info->a[2] / info->a[0];
550         s->tr[4] = info->a[6] * info->y;
551         s->tr[5] = 0;
552         s->tr[6] = info->a[4];
553         s->tr[7] = -info->a[5] / info->a[4];
554     } else {
555         s->tr[0] = info->a[6] * info->y;
556         s->tr[1] = 0;
557         s->tr[2] = info->a[1];
558         s->tr[3] = -info->a[2] / info->a[1];
559         s->tr[4] = 0;
560         s->tr[5] = -info->a[6] * info->x;
561         s->tr[6] = info->a[3];
562         s->tr[7] = -info->a[5] / info->a[3];
563     }
564 
565     s->tr[0] >>= 11;
566     s->tr[1] >>= 11;
567     s->tr[3] <<= 4;
568     s->tr[4] >>= 11;
569     s->tr[5] >>= 11;
570     s->tr[7] <<= 4;
571 }
572