xref: /openbmc/qemu/hw/input/tsc2005.c (revision d36f7de8)
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 "hw/hw.h"
24 #include "qemu/timer.h"
25 #include "ui/console.h"
26 #include "hw/devices.h"
27 #include "trace.h"
28 
29 #define TSC_CUT_RESOLUTION(value, p)	((value) >> (16 - (p ? 12 : 10)))
30 
31 typedef struct {
32     qemu_irq pint;	/* Combination of the nPENIRQ and DAV signals */
33     QEMUTimer *timer;
34     uint16_t model;
35 
36     int32_t x, y;
37     bool pressure;
38 
39     uint8_t reg, state;
40     bool irq, command;
41     uint16_t data, dav;
42 
43     bool busy;
44     bool enabled;
45     bool host_mode;
46     int8_t function;
47     int8_t nextfunction;
48     bool precision;
49     bool nextprecision;
50     uint16_t filter;
51     uint8_t pin_func;
52     uint16_t timing[2];
53     uint8_t noise;
54     bool reset;
55     bool pdst;
56     bool pnd0;
57     uint16_t temp_thr[2];
58     uint16_t aux_thr[2];
59 
60     int32_t tr[8];
61 } TSC2005State;
62 
63 enum {
64     TSC_MODE_XYZ_SCAN	= 0x0,
65     TSC_MODE_XY_SCAN,
66     TSC_MODE_X,
67     TSC_MODE_Y,
68     TSC_MODE_Z,
69     TSC_MODE_AUX,
70     TSC_MODE_TEMP1,
71     TSC_MODE_TEMP2,
72     TSC_MODE_AUX_SCAN,
73     TSC_MODE_X_TEST,
74     TSC_MODE_Y_TEST,
75     TSC_MODE_TS_TEST,
76     TSC_MODE_RESERVED,
77     TSC_MODE_XX_DRV,
78     TSC_MODE_YY_DRV,
79     TSC_MODE_YX_DRV,
80 };
81 
82 static const uint16_t mode_regs[16] = {
83     0xf000,	/* X, Y, Z scan */
84     0xc000,	/* X, Y scan */
85     0x8000,	/* X */
86     0x4000,	/* Y */
87     0x3000,	/* Z */
88     0x0800,	/* AUX */
89     0x0400,	/* TEMP1 */
90     0x0200,	/* TEMP2 */
91     0x0800,	/* AUX scan */
92     0x0040,	/* X test */
93     0x0020,	/* Y test */
94     0x0080,	/* Short-circuit test */
95     0x0000,	/* Reserved */
96     0x0000,	/* X+, X- drivers */
97     0x0000,	/* Y+, Y- drivers */
98     0x0000,	/* Y+, X- drivers */
99 };
100 
101 #define X_TRANSFORM(s)			\
102     ((s->y * s->tr[0] - s->x * s->tr[1]) / s->tr[2] + s->tr[3])
103 #define Y_TRANSFORM(s)			\
104     ((s->y * s->tr[4] - s->x * s->tr[5]) / s->tr[6] + s->tr[7])
105 #define Z1_TRANSFORM(s)			\
106     ((400 - ((s)->x >> 7) + ((s)->pressure << 10)) << 4)
107 #define Z2_TRANSFORM(s)			\
108     ((4000 + ((s)->y >> 7) - ((s)->pressure << 10)) << 4)
109 
110 #define AUX_VAL				(700 << 4)	/* +/- 3 at 12-bit */
111 #define TEMP1_VAL			(1264 << 4)	/* +/- 5 at 12-bit */
112 #define TEMP2_VAL			(1531 << 4)	/* +/- 5 at 12-bit */
113 
114 static uint16_t tsc2005_read(TSC2005State *s, int reg)
115 {
116     uint16_t ret;
117 
118     switch (reg) {
119     case 0x0:	/* X */
120         s->dav &= ~mode_regs[TSC_MODE_X];
121         return TSC_CUT_RESOLUTION(X_TRANSFORM(s), s->precision) +
122                 (s->noise & 3);
123     case 0x1:	/* Y */
124         s->dav &= ~mode_regs[TSC_MODE_Y];
125         s->noise ++;
126         return TSC_CUT_RESOLUTION(Y_TRANSFORM(s), s->precision) ^
127                 (s->noise & 3);
128     case 0x2:	/* Z1 */
129         s->dav &= 0xdfff;
130         return TSC_CUT_RESOLUTION(Z1_TRANSFORM(s), s->precision) -
131                 (s->noise & 3);
132     case 0x3:	/* Z2 */
133         s->dav &= 0xefff;
134         return TSC_CUT_RESOLUTION(Z2_TRANSFORM(s), s->precision) |
135                 (s->noise & 3);
136 
137     case 0x4:	/* AUX */
138         s->dav &= ~mode_regs[TSC_MODE_AUX];
139         return TSC_CUT_RESOLUTION(AUX_VAL, s->precision);
140 
141     case 0x5:	/* TEMP1 */
142         s->dav &= ~mode_regs[TSC_MODE_TEMP1];
143         return TSC_CUT_RESOLUTION(TEMP1_VAL, s->precision) -
144                 (s->noise & 5);
145     case 0x6:	/* TEMP2 */
146         s->dav &= 0xdfff;
147         s->dav &= ~mode_regs[TSC_MODE_TEMP2];
148         return TSC_CUT_RESOLUTION(TEMP2_VAL, s->precision) ^
149                 (s->noise & 3);
150 
151     case 0x7:	/* Status */
152         ret = s->dav | (s->reset << 7) | (s->pdst << 2) | 0x0;
153         s->dav &= ~(mode_regs[TSC_MODE_X_TEST] | mode_regs[TSC_MODE_Y_TEST] |
154                         mode_regs[TSC_MODE_TS_TEST]);
155         s->reset = true;
156         return ret;
157 
158     case 0x8:	/* AUX high treshold */
159         return s->aux_thr[1];
160     case 0x9:	/* AUX low treshold */
161         return s->aux_thr[0];
162 
163     case 0xa:	/* TEMP high treshold */
164         return s->temp_thr[1];
165     case 0xb:	/* TEMP low treshold */
166         return s->temp_thr[0];
167 
168     case 0xc:	/* CFR0 */
169         return (s->pressure << 15) | ((!s->busy) << 14) |
170                 (s->nextprecision << 13) | s->timing[0];
171     case 0xd:	/* CFR1 */
172         return s->timing[1];
173     case 0xe:	/* CFR2 */
174         return (s->pin_func << 14) | s->filter;
175 
176     case 0xf:	/* Function select status */
177         return s->function >= 0 ? 1 << s->function : 0;
178     }
179 
180     /* Never gets here */
181     return 0xffff;
182 }
183 
184 static void tsc2005_write(TSC2005State *s, int reg, uint16_t data)
185 {
186     switch (reg) {
187     case 0x8:	/* AUX high treshold */
188         s->aux_thr[1] = data;
189         break;
190     case 0x9:	/* AUX low treshold */
191         s->aux_thr[0] = data;
192         break;
193 
194     case 0xa:	/* TEMP high treshold */
195         s->temp_thr[1] = data;
196         break;
197     case 0xb:	/* TEMP low treshold */
198         s->temp_thr[0] = data;
199         break;
200 
201     case 0xc:	/* CFR0 */
202         s->host_mode = (data >> 15) != 0;
203         if (s->enabled != !(data & 0x4000)) {
204             s->enabled = !(data & 0x4000);
205             trace_tsc2005_sense(s->enabled ? "enabled" : "disabled");
206             if (s->busy && !s->enabled)
207                 timer_del(s->timer);
208             s->busy = s->busy && s->enabled;
209         }
210         s->nextprecision = (data >> 13) & 1;
211         s->timing[0] = data & 0x1fff;
212         if ((s->timing[0] >> 11) == 3) {
213             qemu_log_mask(LOG_GUEST_ERROR,
214                           "tsc2005_write: illegal conversion clock setting\n");
215         }
216         break;
217     case 0xd:	/* CFR1 */
218         s->timing[1] = data & 0xf07;
219         break;
220     case 0xe:	/* CFR2 */
221         s->pin_func = (data >> 14) & 3;
222         s->filter = data & 0x3fff;
223         break;
224 
225     default:
226         qemu_log_mask(LOG_GUEST_ERROR,
227                       "%s: write into read-only register 0x%x\n",
228                       __func__, reg);
229     }
230 }
231 
232 /* This handles most of the chip's logic.  */
233 static void tsc2005_pin_update(TSC2005State *s)
234 {
235     int64_t expires;
236     bool pin_state;
237 
238     switch (s->pin_func) {
239     case 0:
240         pin_state = !s->pressure && !!s->dav;
241         break;
242     case 1:
243     case 3:
244     default:
245         pin_state = !s->dav;
246         break;
247     case 2:
248         pin_state = !s->pressure;
249     }
250 
251     if (pin_state != s->irq) {
252         s->irq = pin_state;
253         qemu_set_irq(s->pint, s->irq);
254     }
255 
256     switch (s->nextfunction) {
257     case TSC_MODE_XYZ_SCAN:
258     case TSC_MODE_XY_SCAN:
259         if (!s->host_mode && s->dav)
260             s->enabled = false;
261         if (!s->pressure)
262             return;
263         /* Fall through */
264     case TSC_MODE_AUX_SCAN:
265         break;
266 
267     case TSC_MODE_X:
268     case TSC_MODE_Y:
269     case TSC_MODE_Z:
270         if (!s->pressure)
271             return;
272         /* Fall through */
273     case TSC_MODE_AUX:
274     case TSC_MODE_TEMP1:
275     case TSC_MODE_TEMP2:
276     case TSC_MODE_X_TEST:
277     case TSC_MODE_Y_TEST:
278     case TSC_MODE_TS_TEST:
279         if (s->dav)
280             s->enabled = false;
281         break;
282 
283     case TSC_MODE_RESERVED:
284     case TSC_MODE_XX_DRV:
285     case TSC_MODE_YY_DRV:
286     case TSC_MODE_YX_DRV:
287     default:
288         return;
289     }
290 
291     if (!s->enabled || s->busy)
292         return;
293 
294     s->busy = true;
295     s->precision = s->nextprecision;
296     s->function = s->nextfunction;
297     s->pdst = !s->pnd0;	/* Synchronised on internal clock */
298     expires = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
299         (NANOSECONDS_PER_SECOND >> 7);
300     timer_mod(s->timer, expires);
301 }
302 
303 static void tsc2005_reset(TSC2005State *s)
304 {
305     s->state = 0;
306     s->pin_func = 0;
307     s->enabled = false;
308     s->busy = false;
309     s->nextprecision = false;
310     s->nextfunction = 0;
311     s->timing[0] = 0;
312     s->timing[1] = 0;
313     s->irq = false;
314     s->dav = 0;
315     s->reset = false;
316     s->pdst = true;
317     s->pnd0 = false;
318     s->function = -1;
319     s->temp_thr[0] = 0x000;
320     s->temp_thr[1] = 0xfff;
321     s->aux_thr[0] = 0x000;
322     s->aux_thr[1] = 0xfff;
323 
324     tsc2005_pin_update(s);
325 }
326 
327 static uint8_t tsc2005_txrx_word(void *opaque, uint8_t value)
328 {
329     TSC2005State *s = opaque;
330     uint32_t ret = 0;
331 
332     switch (s->state ++) {
333     case 0:
334         if (value & 0x80) {
335             /* Command */
336             if (value & (1 << 1))
337                 tsc2005_reset(s);
338             else {
339                 s->nextfunction = (value >> 3) & 0xf;
340                 s->nextprecision = (value >> 2) & 1;
341                 if (s->enabled != !(value & 1)) {
342                     s->enabled = !(value & 1);
343                     trace_tsc2005_sense(s->enabled ? "enabled" : "disabled");
344                     if (s->busy && !s->enabled)
345                         timer_del(s->timer);
346                     s->busy = s->busy && s->enabled;
347                 }
348                 tsc2005_pin_update(s);
349             }
350 
351             s->state = 0;
352         } else if (value) {
353             /* Data transfer */
354             s->reg = (value >> 3) & 0xf;
355             s->pnd0 = (value >> 1) & 1;
356             s->command = value & 1;
357 
358             if (s->command) {
359                 /* Read */
360                 s->data = tsc2005_read(s, s->reg);
361                 tsc2005_pin_update(s);
362             } else
363                 s->data = 0;
364         } else
365             s->state = 0;
366         break;
367 
368     case 1:
369         if (s->command)
370             ret = (s->data >> 8) & 0xff;
371         else
372             s->data |= value << 8;
373         break;
374 
375     case 2:
376         if (s->command)
377             ret = s->data & 0xff;
378         else {
379             s->data |= value;
380             tsc2005_write(s, s->reg, s->data);
381             tsc2005_pin_update(s);
382         }
383 
384         s->state = 0;
385         break;
386     }
387 
388     return ret;
389 }
390 
391 uint32_t tsc2005_txrx(void *opaque, uint32_t value, int len)
392 {
393     uint32_t ret = 0;
394 
395     len &= ~7;
396     while (len > 0) {
397         len -= 8;
398         ret |= tsc2005_txrx_word(opaque, (value >> len) & 0xff) << len;
399     }
400 
401     return ret;
402 }
403 
404 static void tsc2005_timer_tick(void *opaque)
405 {
406     TSC2005State *s = opaque;
407 
408     /* Timer ticked -- a set of conversions has been finished.  */
409 
410     if (!s->busy)
411         return;
412 
413     s->busy = false;
414     s->dav |= mode_regs[s->function];
415     s->function = -1;
416     tsc2005_pin_update(s);
417 }
418 
419 static void tsc2005_touchscreen_event(void *opaque,
420                 int x, int y, int z, int buttons_state)
421 {
422     TSC2005State *s = opaque;
423     int p = s->pressure;
424 
425     if (buttons_state) {
426         s->x = x;
427         s->y = y;
428     }
429     s->pressure = !!buttons_state;
430 
431     /*
432      * Note: We would get better responsiveness in the guest by
433      * signaling TS events immediately, but for now we simulate
434      * the first conversion delay for sake of correctness.
435      */
436     if (p != s->pressure)
437         tsc2005_pin_update(s);
438 }
439 
440 static int tsc2005_post_load(void *opaque, int version_id)
441 {
442     TSC2005State *s = (TSC2005State *) opaque;
443 
444     s->busy = timer_pending(s->timer);
445     tsc2005_pin_update(s);
446 
447     return 0;
448 }
449 
450 static const VMStateDescription vmstate_tsc2005 = {
451     .name = "tsc2005",
452     .version_id = 2,
453     .minimum_version_id = 2,
454     .post_load = tsc2005_post_load,
455     .fields      = (VMStateField []) {
456         VMSTATE_BOOL(pressure, TSC2005State),
457         VMSTATE_BOOL(irq, TSC2005State),
458         VMSTATE_BOOL(command, TSC2005State),
459         VMSTATE_BOOL(enabled, TSC2005State),
460         VMSTATE_BOOL(host_mode, TSC2005State),
461         VMSTATE_BOOL(reset, TSC2005State),
462         VMSTATE_BOOL(pdst, TSC2005State),
463         VMSTATE_BOOL(pnd0, TSC2005State),
464         VMSTATE_BOOL(precision, TSC2005State),
465         VMSTATE_BOOL(nextprecision, TSC2005State),
466         VMSTATE_UINT8(reg, TSC2005State),
467         VMSTATE_UINT8(state, TSC2005State),
468         VMSTATE_UINT16(data, TSC2005State),
469         VMSTATE_UINT16(dav, TSC2005State),
470         VMSTATE_UINT16(filter, TSC2005State),
471         VMSTATE_INT8(nextfunction, TSC2005State),
472         VMSTATE_INT8(function, TSC2005State),
473         VMSTATE_INT32(x, TSC2005State),
474         VMSTATE_INT32(y, TSC2005State),
475         VMSTATE_TIMER_PTR(timer, TSC2005State),
476         VMSTATE_UINT8(pin_func, TSC2005State),
477         VMSTATE_UINT16_ARRAY(timing, TSC2005State, 2),
478         VMSTATE_UINT8(noise, TSC2005State),
479         VMSTATE_UINT16_ARRAY(temp_thr, TSC2005State, 2),
480         VMSTATE_UINT16_ARRAY(aux_thr, TSC2005State, 2),
481         VMSTATE_INT32_ARRAY(tr, TSC2005State, 8),
482         VMSTATE_END_OF_LIST()
483     }
484 };
485 
486 void *tsc2005_init(qemu_irq pintdav)
487 {
488     TSC2005State *s;
489 
490     s = (TSC2005State *)
491             g_malloc0(sizeof(TSC2005State));
492     s->x = 400;
493     s->y = 240;
494     s->pressure = false;
495     s->precision = s->nextprecision = false;
496     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, tsc2005_timer_tick, s);
497     s->pint = pintdav;
498     s->model = 0x2005;
499 
500     s->tr[0] = 0;
501     s->tr[1] = 1;
502     s->tr[2] = 1;
503     s->tr[3] = 0;
504     s->tr[4] = 1;
505     s->tr[5] = 0;
506     s->tr[6] = 1;
507     s->tr[7] = 0;
508 
509     tsc2005_reset(s);
510 
511     qemu_add_mouse_event_handler(tsc2005_touchscreen_event, s, 1,
512                     "QEMU TSC2005-driven Touchscreen");
513 
514     qemu_register_reset((void *) tsc2005_reset, s);
515     vmstate_register(NULL, 0, &vmstate_tsc2005, s);
516 
517     return s;
518 }
519 
520 /*
521  * Use tslib generated calibration data to generate ADC input values
522  * from the touchscreen.  Assuming 12-bit precision was used during
523  * tslib calibration.
524  */
525 void tsc2005_set_transform(void *opaque, MouseTransformInfo *info)
526 {
527     TSC2005State *s = (TSC2005State *) opaque;
528 
529     /* This version assumes touchscreen X & Y axis are parallel or
530      * perpendicular to LCD's  X & Y axis in some way.  */
531     if (abs(info->a[0]) > abs(info->a[1])) {
532         s->tr[0] = 0;
533         s->tr[1] = -info->a[6] * info->x;
534         s->tr[2] = info->a[0];
535         s->tr[3] = -info->a[2] / info->a[0];
536         s->tr[4] = info->a[6] * info->y;
537         s->tr[5] = 0;
538         s->tr[6] = info->a[4];
539         s->tr[7] = -info->a[5] / info->a[4];
540     } else {
541         s->tr[0] = info->a[6] * info->y;
542         s->tr[1] = 0;
543         s->tr[2] = info->a[1];
544         s->tr[3] = -info->a[2] / info->a[1];
545         s->tr[4] = 0;
546         s->tr[5] = -info->a[6] * info->x;
547         s->tr[6] = info->a[3];
548         s->tr[7] = -info->a[5] / info->a[3];
549     }
550 
551     s->tr[0] >>= 11;
552     s->tr[1] >>= 11;
553     s->tr[3] <<= 4;
554     s->tr[4] >>= 11;
555     s->tr[5] >>= 11;
556     s->tr[7] <<= 4;
557 }
558