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Linux/sound/soc/omap/ams-delta.c

  1 /*
  2  * ams-delta.c  --  SoC audio for Amstrad E3 (Delta) videophone
  3  *
  4  * Copyright (C) 2009 Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
  5  *
  6  * Initially based on sound/soc/omap/osk5912.x
  7  * Copyright (C) 2008 Mistral Solutions
  8  *
  9  * This program is free software; you can redistribute it and/or
 10  * modify it under the terms of the GNU General Public License
 11  * version 2 as published by the Free Software Foundation.
 12  *
 13  * This program is distributed in the hope that it will be useful, but
 14  * WITHOUT ANY WARRANTY; without even the implied warranty of
 15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 16  * General Public License for more details.
 17  *
 18  * You should have received a copy of the GNU General Public License
 19  * along with this program; if not, write to the Free Software
 20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 21  * 02110-1301 USA
 22  *
 23  */
 24 
 25 #include <linux/gpio.h>
 26 #include <linux/spinlock.h>
 27 #include <linux/tty.h>
 28 #include <linux/module.h>
 29 
 30 #include <sound/soc.h>
 31 #include <sound/jack.h>
 32 
 33 #include <asm/mach-types.h>
 34 
 35 #include <mach/board-ams-delta.h>
 36 #include <linux/platform_data/asoc-ti-mcbsp.h>
 37 
 38 #include "omap-mcbsp.h"
 39 #include "../codecs/cx20442.h"
 40 
 41 
 42 /* Board specific DAPM widgets */
 43 static const struct snd_soc_dapm_widget ams_delta_dapm_widgets[] = {
 44         /* Handset */
 45         SND_SOC_DAPM_MIC("Mouthpiece", NULL),
 46         SND_SOC_DAPM_HP("Earpiece", NULL),
 47         /* Handsfree/Speakerphone */
 48         SND_SOC_DAPM_MIC("Microphone", NULL),
 49         SND_SOC_DAPM_SPK("Speaker", NULL),
 50 };
 51 
 52 /* How they are connected to codec pins */
 53 static const struct snd_soc_dapm_route ams_delta_audio_map[] = {
 54         {"TELIN", NULL, "Mouthpiece"},
 55         {"Earpiece", NULL, "TELOUT"},
 56 
 57         {"MIC", NULL, "Microphone"},
 58         {"Speaker", NULL, "SPKOUT"},
 59 };
 60 
 61 /*
 62  * Controls, functional after the modem line discipline is activated.
 63  */
 64 
 65 /* Virtual switch: audio input/output constellations */
 66 static const char *ams_delta_audio_mode[] =
 67         {"Mixed", "Handset", "Handsfree", "Speakerphone"};
 68 
 69 /* Selection <-> pin translation */
 70 #define AMS_DELTA_MOUTHPIECE    0
 71 #define AMS_DELTA_EARPIECE      1
 72 #define AMS_DELTA_MICROPHONE    2
 73 #define AMS_DELTA_SPEAKER       3
 74 #define AMS_DELTA_AGC           4
 75 
 76 #define AMS_DELTA_MIXED         ((1 << AMS_DELTA_EARPIECE) | \
 77                                                 (1 << AMS_DELTA_MICROPHONE))
 78 #define AMS_DELTA_HANDSET       ((1 << AMS_DELTA_MOUTHPIECE) | \
 79                                                 (1 << AMS_DELTA_EARPIECE))
 80 #define AMS_DELTA_HANDSFREE     ((1 << AMS_DELTA_MICROPHONE) | \
 81                                                 (1 << AMS_DELTA_SPEAKER))
 82 #define AMS_DELTA_SPEAKERPHONE  (AMS_DELTA_HANDSFREE | (1 << AMS_DELTA_AGC))
 83 
 84 static const unsigned short ams_delta_audio_mode_pins[] = {
 85         AMS_DELTA_MIXED,
 86         AMS_DELTA_HANDSET,
 87         AMS_DELTA_HANDSFREE,
 88         AMS_DELTA_SPEAKERPHONE,
 89 };
 90 
 91 static unsigned short ams_delta_audio_agc;
 92 
 93 static int ams_delta_set_audio_mode(struct snd_kcontrol *kcontrol,
 94                                         struct snd_ctl_elem_value *ucontrol)
 95 {
 96         struct snd_soc_codec *codec =  snd_kcontrol_chip(kcontrol);
 97         struct snd_soc_dapm_context *dapm = &codec->dapm;
 98         struct soc_enum *control = (struct soc_enum *)kcontrol->private_value;
 99         unsigned short pins;
100         int pin, changed = 0;
101 
102         /* Refuse any mode changes if we are not able to control the codec. */
103         if (!codec->hw_write)
104                 return -EUNATCH;
105 
106         if (ucontrol->value.enumerated.item[0] >= control->max)
107                 return -EINVAL;
108 
109         mutex_lock(&codec->mutex);
110 
111         /* Translate selection to bitmap */
112         pins = ams_delta_audio_mode_pins[ucontrol->value.enumerated.item[0]];
113 
114         /* Setup pins after corresponding bits if changed */
115         pin = !!(pins & (1 << AMS_DELTA_MOUTHPIECE));
116         if (pin != snd_soc_dapm_get_pin_status(dapm, "Mouthpiece")) {
117                 changed = 1;
118                 if (pin)
119                         snd_soc_dapm_enable_pin(dapm, "Mouthpiece");
120                 else
121                         snd_soc_dapm_disable_pin(dapm, "Mouthpiece");
122         }
123         pin = !!(pins & (1 << AMS_DELTA_EARPIECE));
124         if (pin != snd_soc_dapm_get_pin_status(dapm, "Earpiece")) {
125                 changed = 1;
126                 if (pin)
127                         snd_soc_dapm_enable_pin(dapm, "Earpiece");
128                 else
129                         snd_soc_dapm_disable_pin(dapm, "Earpiece");
130         }
131         pin = !!(pins & (1 << AMS_DELTA_MICROPHONE));
132         if (pin != snd_soc_dapm_get_pin_status(dapm, "Microphone")) {
133                 changed = 1;
134                 if (pin)
135                         snd_soc_dapm_enable_pin(dapm, "Microphone");
136                 else
137                         snd_soc_dapm_disable_pin(dapm, "Microphone");
138         }
139         pin = !!(pins & (1 << AMS_DELTA_SPEAKER));
140         if (pin != snd_soc_dapm_get_pin_status(dapm, "Speaker")) {
141                 changed = 1;
142                 if (pin)
143                         snd_soc_dapm_enable_pin(dapm, "Speaker");
144                 else
145                         snd_soc_dapm_disable_pin(dapm, "Speaker");
146         }
147         pin = !!(pins & (1 << AMS_DELTA_AGC));
148         if (pin != ams_delta_audio_agc) {
149                 ams_delta_audio_agc = pin;
150                 changed = 1;
151                 if (pin)
152                         snd_soc_dapm_enable_pin(dapm, "AGCIN");
153                 else
154                         snd_soc_dapm_disable_pin(dapm, "AGCIN");
155         }
156         if (changed)
157                 snd_soc_dapm_sync(dapm);
158 
159         mutex_unlock(&codec->mutex);
160 
161         return changed;
162 }
163 
164 static int ams_delta_get_audio_mode(struct snd_kcontrol *kcontrol,
165                                         struct snd_ctl_elem_value *ucontrol)
166 {
167         struct snd_soc_codec *codec =  snd_kcontrol_chip(kcontrol);
168         struct snd_soc_dapm_context *dapm = &codec->dapm;
169         unsigned short pins, mode;
170 
171         pins = ((snd_soc_dapm_get_pin_status(dapm, "Mouthpiece") <<
172                                                         AMS_DELTA_MOUTHPIECE) |
173                         (snd_soc_dapm_get_pin_status(dapm, "Earpiece") <<
174                                                         AMS_DELTA_EARPIECE));
175         if (pins)
176                 pins |= (snd_soc_dapm_get_pin_status(dapm, "Microphone") <<
177                                                         AMS_DELTA_MICROPHONE);
178         else
179                 pins = ((snd_soc_dapm_get_pin_status(dapm, "Microphone") <<
180                                                         AMS_DELTA_MICROPHONE) |
181                         (snd_soc_dapm_get_pin_status(dapm, "Speaker") <<
182                                                         AMS_DELTA_SPEAKER) |
183                         (ams_delta_audio_agc << AMS_DELTA_AGC));
184 
185         for (mode = 0; mode < ARRAY_SIZE(ams_delta_audio_mode); mode++)
186                 if (pins == ams_delta_audio_mode_pins[mode])
187                         break;
188 
189         if (mode >= ARRAY_SIZE(ams_delta_audio_mode))
190                 return -EINVAL;
191 
192         ucontrol->value.enumerated.item[0] = mode;
193 
194         return 0;
195 }
196 
197 static const struct soc_enum ams_delta_audio_enum[] = {
198         SOC_ENUM_SINGLE_EXT(ARRAY_SIZE(ams_delta_audio_mode),
199                                                 ams_delta_audio_mode),
200 };
201 
202 static const struct snd_kcontrol_new ams_delta_audio_controls[] = {
203         SOC_ENUM_EXT("Audio Mode", ams_delta_audio_enum[0],
204                         ams_delta_get_audio_mode, ams_delta_set_audio_mode),
205 };
206 
207 /* Hook switch */
208 static struct snd_soc_jack ams_delta_hook_switch;
209 static struct snd_soc_jack_gpio ams_delta_hook_switch_gpios[] = {
210         {
211                 .gpio = 4,
212                 .name = "hook_switch",
213                 .report = SND_JACK_HEADSET,
214                 .invert = 1,
215                 .debounce_time = 150,
216         }
217 };
218 
219 /* After we are able to control the codec over the modem,
220  * the hook switch can be used for dynamic DAPM reconfiguration. */
221 static struct snd_soc_jack_pin ams_delta_hook_switch_pins[] = {
222         /* Handset */
223         {
224                 .pin = "Mouthpiece",
225                 .mask = SND_JACK_MICROPHONE,
226         },
227         {
228                 .pin = "Earpiece",
229                 .mask = SND_JACK_HEADPHONE,
230         },
231         /* Handsfree */
232         {
233                 .pin = "Microphone",
234                 .mask = SND_JACK_MICROPHONE,
235                 .invert = 1,
236         },
237         {
238                 .pin = "Speaker",
239                 .mask = SND_JACK_HEADPHONE,
240                 .invert = 1,
241         },
242 };
243 
244 
245 /*
246  * Modem line discipline, required for making above controls functional.
247  * Activated from userspace with ldattach, possibly invoked from udev rule.
248  */
249 
250 /* To actually apply any modem controlled configuration changes to the codec,
251  * we must connect codec DAI pins to the modem for a moment.  Be careful not
252  * to interfere with our digital mute function that shares the same hardware. */
253 static struct timer_list cx81801_timer;
254 static bool cx81801_cmd_pending;
255 static bool ams_delta_muted;
256 static DEFINE_SPINLOCK(ams_delta_lock);
257 
258 static void cx81801_timeout(unsigned long data)
259 {
260         int muted;
261 
262         spin_lock(&ams_delta_lock);
263         cx81801_cmd_pending = 0;
264         muted = ams_delta_muted;
265         spin_unlock(&ams_delta_lock);
266 
267         /* Reconnect the codec DAI back from the modem to the CPU DAI
268          * only if digital mute still off */
269         if (!muted)
270                 ams_delta_latch2_write(AMS_DELTA_LATCH2_MODEM_CODEC, 0);
271 }
272 
273 /*
274  * Used for passing a codec structure pointer
275  * from the board initialization code to the tty line discipline.
276  */
277 static struct snd_soc_codec *cx20442_codec;
278 
279 /* Line discipline .open() */
280 static int cx81801_open(struct tty_struct *tty)
281 {
282         int ret;
283 
284         if (!cx20442_codec)
285                 return -ENODEV;
286 
287         /*
288          * Pass the codec structure pointer for use by other ldisc callbacks,
289          * both the card and the codec specific parts.
290          */
291         tty->disc_data = cx20442_codec;
292 
293         ret = v253_ops.open(tty);
294 
295         if (ret < 0)
296                 tty->disc_data = NULL;
297 
298         return ret;
299 }
300 
301 /* Line discipline .close() */
302 static void cx81801_close(struct tty_struct *tty)
303 {
304         struct snd_soc_codec *codec = tty->disc_data;
305         struct snd_soc_dapm_context *dapm = &codec->dapm;
306 
307         del_timer_sync(&cx81801_timer);
308 
309         /* Prevent the hook switch from further changing the DAPM pins */
310         INIT_LIST_HEAD(&ams_delta_hook_switch.pins);
311 
312         if (!codec)
313                 return;
314 
315         v253_ops.close(tty);
316 
317         /* Revert back to default audio input/output constellation */
318         snd_soc_dapm_disable_pin(dapm, "Mouthpiece");
319         snd_soc_dapm_enable_pin(dapm, "Earpiece");
320         snd_soc_dapm_enable_pin(dapm, "Microphone");
321         snd_soc_dapm_disable_pin(dapm, "Speaker");
322         snd_soc_dapm_disable_pin(dapm, "AGCIN");
323         snd_soc_dapm_sync(dapm);
324 }
325 
326 /* Line discipline .hangup() */
327 static int cx81801_hangup(struct tty_struct *tty)
328 {
329         cx81801_close(tty);
330         return 0;
331 }
332 
333 /* Line discipline .receive_buf() */
334 static void cx81801_receive(struct tty_struct *tty,
335                                 const unsigned char *cp, char *fp, int count)
336 {
337         struct snd_soc_codec *codec = tty->disc_data;
338         const unsigned char *c;
339         int apply, ret;
340 
341         if (!codec)
342                 return;
343 
344         if (!codec->hw_write) {
345                 /* First modem response, complete setup procedure */
346 
347                 /* Initialize timer used for config pulse generation */
348                 setup_timer(&cx81801_timer, cx81801_timeout, 0);
349 
350                 v253_ops.receive_buf(tty, cp, fp, count);
351 
352                 /* Link hook switch to DAPM pins */
353                 ret = snd_soc_jack_add_pins(&ams_delta_hook_switch,
354                                         ARRAY_SIZE(ams_delta_hook_switch_pins),
355                                         ams_delta_hook_switch_pins);
356                 if (ret)
357                         dev_warn(codec->dev,
358                                 "Failed to link hook switch to DAPM pins, "
359                                 "will continue with hook switch unlinked.\n");
360 
361                 return;
362         }
363 
364         v253_ops.receive_buf(tty, cp, fp, count);
365 
366         for (c = &cp[count - 1]; c >= cp; c--) {
367                 if (*c != '\r')
368                         continue;
369                 /* Complete modem response received, apply config to codec */
370 
371                 spin_lock_bh(&ams_delta_lock);
372                 mod_timer(&cx81801_timer, jiffies + msecs_to_jiffies(150));
373                 apply = !ams_delta_muted && !cx81801_cmd_pending;
374                 cx81801_cmd_pending = 1;
375                 spin_unlock_bh(&ams_delta_lock);
376 
377                 /* Apply config pulse by connecting the codec to the modem
378                  * if not already done */
379                 if (apply)
380                         ams_delta_latch2_write(AMS_DELTA_LATCH2_MODEM_CODEC,
381                                                 AMS_DELTA_LATCH2_MODEM_CODEC);
382                 break;
383         }
384 }
385 
386 /* Line discipline .write_wakeup() */
387 static void cx81801_wakeup(struct tty_struct *tty)
388 {
389         v253_ops.write_wakeup(tty);
390 }
391 
392 static struct tty_ldisc_ops cx81801_ops = {
393         .magic = TTY_LDISC_MAGIC,
394         .name = "cx81801",
395         .owner = THIS_MODULE,
396         .open = cx81801_open,
397         .close = cx81801_close,
398         .hangup = cx81801_hangup,
399         .receive_buf = cx81801_receive,
400         .write_wakeup = cx81801_wakeup,
401 };
402 
403 
404 /*
405  * Even if not very useful, the sound card can still work without any of the
406  * above functonality activated.  You can still control its audio input/output
407  * constellation and speakerphone gain from userspace by issuing AT commands
408  * over the modem port.
409  */
410 
411 static int ams_delta_hw_params(struct snd_pcm_substream *substream,
412                          struct snd_pcm_hw_params *params)
413 {
414         struct snd_soc_pcm_runtime *rtd = substream->private_data;
415 
416         /* Set cpu DAI configuration */
417         return snd_soc_dai_set_fmt(rtd->cpu_dai,
418                                    SND_SOC_DAIFMT_DSP_A |
419                                    SND_SOC_DAIFMT_NB_NF |
420                                    SND_SOC_DAIFMT_CBM_CFM);
421 }
422 
423 static struct snd_soc_ops ams_delta_ops = {
424         .hw_params = ams_delta_hw_params,
425 };
426 
427 
428 /* Digital mute implemented using modem/CPU multiplexer.
429  * Shares hardware with codec config pulse generation */
430 static bool ams_delta_muted = 1;
431 
432 static int ams_delta_digital_mute(struct snd_soc_dai *dai, int mute)
433 {
434         int apply;
435 
436         if (ams_delta_muted == mute)
437                 return 0;
438 
439         spin_lock_bh(&ams_delta_lock);
440         ams_delta_muted = mute;
441         apply = !cx81801_cmd_pending;
442         spin_unlock_bh(&ams_delta_lock);
443 
444         if (apply)
445                 ams_delta_latch2_write(AMS_DELTA_LATCH2_MODEM_CODEC,
446                                 mute ? AMS_DELTA_LATCH2_MODEM_CODEC : 0);
447         return 0;
448 }
449 
450 /* Our codec DAI probably doesn't have its own .ops structure */
451 static const struct snd_soc_dai_ops ams_delta_dai_ops = {
452         .digital_mute = ams_delta_digital_mute,
453 };
454 
455 /* Will be used if the codec ever has its own digital_mute function */
456 static int ams_delta_startup(struct snd_pcm_substream *substream)
457 {
458         return ams_delta_digital_mute(NULL, 0);
459 }
460 
461 static void ams_delta_shutdown(struct snd_pcm_substream *substream)
462 {
463         ams_delta_digital_mute(NULL, 1);
464 }
465 
466 
467 /*
468  * Card initialization
469  */
470 
471 static int ams_delta_cx20442_init(struct snd_soc_pcm_runtime *rtd)
472 {
473         struct snd_soc_codec *codec = rtd->codec;
474         struct snd_soc_dapm_context *dapm = &codec->dapm;
475         struct snd_soc_dai *codec_dai = rtd->codec_dai;
476         struct snd_soc_card *card = rtd->card;
477         int ret;
478         /* Codec is ready, now add/activate board specific controls */
479 
480         /* Store a pointer to the codec structure for tty ldisc use */
481         cx20442_codec = codec;
482 
483         /* Set up digital mute if not provided by the codec */
484         if (!codec_dai->driver->ops) {
485                 codec_dai->driver->ops = &ams_delta_dai_ops;
486         } else {
487                 ams_delta_ops.startup = ams_delta_startup;
488                 ams_delta_ops.shutdown = ams_delta_shutdown;
489         }
490 
491         /* Add hook switch - can be used to control the codec from userspace
492          * even if line discipline fails */
493         ret = snd_soc_jack_new(rtd->codec, "hook_switch",
494                                 SND_JACK_HEADSET, &ams_delta_hook_switch);
495         if (ret)
496                 dev_warn(card->dev,
497                                 "Failed to allocate resources for hook switch, "
498                                 "will continue without one.\n");
499         else {
500                 ret = snd_soc_jack_add_gpios(&ams_delta_hook_switch,
501                                         ARRAY_SIZE(ams_delta_hook_switch_gpios),
502                                         ams_delta_hook_switch_gpios);
503                 if (ret)
504                         dev_warn(card->dev,
505                                 "Failed to set up hook switch GPIO line, "
506                                 "will continue with hook switch inactive.\n");
507         }
508 
509         /* Register optional line discipline for over the modem control */
510         ret = tty_register_ldisc(N_V253, &cx81801_ops);
511         if (ret) {
512                 dev_warn(card->dev,
513                                 "Failed to register line discipline, "
514                                 "will continue without any controls.\n");
515                 return 0;
516         }
517 
518         /* Add board specific DAPM widgets and routes */
519         ret = snd_soc_dapm_new_controls(dapm, ams_delta_dapm_widgets,
520                                         ARRAY_SIZE(ams_delta_dapm_widgets));
521         if (ret) {
522                 dev_warn(card->dev,
523                                 "Failed to register DAPM controls, "
524                                 "will continue without any.\n");
525                 return 0;
526         }
527 
528         ret = snd_soc_dapm_add_routes(dapm, ams_delta_audio_map,
529                                         ARRAY_SIZE(ams_delta_audio_map));
530         if (ret) {
531                 dev_warn(card->dev,
532                                 "Failed to set up DAPM routes, "
533                                 "will continue with codec default map.\n");
534                 return 0;
535         }
536 
537         /* Set up initial pin constellation */
538         snd_soc_dapm_disable_pin(dapm, "Mouthpiece");
539         snd_soc_dapm_enable_pin(dapm, "Earpiece");
540         snd_soc_dapm_enable_pin(dapm, "Microphone");
541         snd_soc_dapm_disable_pin(dapm, "Speaker");
542         snd_soc_dapm_disable_pin(dapm, "AGCIN");
543         snd_soc_dapm_disable_pin(dapm, "AGCOUT");
544 
545         /* Add virtual switch */
546         ret = snd_soc_add_codec_controls(codec, ams_delta_audio_controls,
547                                         ARRAY_SIZE(ams_delta_audio_controls));
548         if (ret)
549                 dev_warn(card->dev,
550                                 "Failed to register audio mode control, "
551                                 "will continue without it.\n");
552 
553         return 0;
554 }
555 
556 /* DAI glue - connects codec <--> CPU */
557 static struct snd_soc_dai_link ams_delta_dai_link = {
558         .name = "CX20442",
559         .stream_name = "CX20442",
560         .cpu_dai_name = "omap-mcbsp.1",
561         .codec_dai_name = "cx20442-voice",
562         .init = ams_delta_cx20442_init,
563         .platform_name = "omap-pcm-audio",
564         .codec_name = "cx20442-codec",
565         .ops = &ams_delta_ops,
566 };
567 
568 /* Audio card driver */
569 static struct snd_soc_card ams_delta_audio_card = {
570         .name = "AMS_DELTA",
571         .owner = THIS_MODULE,
572         .dai_link = &ams_delta_dai_link,
573         .num_links = 1,
574 };
575 
576 /* Module init/exit */
577 static int ams_delta_probe(struct platform_device *pdev)
578 {
579         struct snd_soc_card *card = &ams_delta_audio_card;
580         int ret;
581 
582         card->dev = &pdev->dev;
583 
584         ret = snd_soc_register_card(card);
585         if (ret) {
586                 dev_err(&pdev->dev, "snd_soc_register_card failed (%d)\n", ret);
587                 card->dev = NULL;
588                 return ret;
589         }
590         return 0;
591 }
592 
593 static int ams_delta_remove(struct platform_device *pdev)
594 {
595         struct snd_soc_card *card = platform_get_drvdata(pdev);
596 
597         if (tty_unregister_ldisc(N_V253) != 0)
598                 dev_warn(&pdev->dev,
599                         "failed to unregister V253 line discipline\n");
600 
601         snd_soc_jack_free_gpios(&ams_delta_hook_switch,
602                         ARRAY_SIZE(ams_delta_hook_switch_gpios),
603                         ams_delta_hook_switch_gpios);
604 
605         snd_soc_unregister_card(card);
606         card->dev = NULL;
607         return 0;
608 }
609 
610 #define DRV_NAME "ams-delta-audio"
611 
612 static struct platform_driver ams_delta_driver = {
613         .driver = {
614                 .name = DRV_NAME,
615                 .owner = THIS_MODULE,
616         },
617         .probe = ams_delta_probe,
618         .remove = ams_delta_remove,
619 };
620 
621 module_platform_driver(ams_delta_driver);
622 
623 MODULE_AUTHOR("Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>");
624 MODULE_DESCRIPTION("ALSA SoC driver for Amstrad E3 (Delta) videophone");
625 MODULE_LICENSE("GPL");
626 MODULE_ALIAS("platform:" DRV_NAME);
627 

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