ALSA: control: Add verification for kctl accesses
[muen/linux.git] / sound / sh / sh_dac_audio.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * sh_dac_audio.c - SuperH DAC audio driver for ALSA
4  *
5  * Copyright (c) 2009 by Rafael Ignacio Zurita <rizurita@yahoo.com>
6  *
7  * Based on sh_dac_audio.c (Copyright (C) 2004, 2005 by Andriy Skulysh)
8  */
9
10 #include <linux/hrtimer.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/platform_device.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 #include <sound/core.h>
17 #include <sound/initval.h>
18 #include <sound/pcm.h>
19 #include <sound/sh_dac_audio.h>
20 #include <asm/clock.h>
21 #include <asm/hd64461.h>
22 #include <mach/hp6xx.h>
23 #include <cpu/dac.h>
24
25 MODULE_AUTHOR("Rafael Ignacio Zurita <rizurita@yahoo.com>");
26 MODULE_DESCRIPTION("SuperH DAC audio driver");
27 MODULE_LICENSE("GPL");
28 MODULE_SUPPORTED_DEVICE("{{SuperH DAC audio support}}");
29
30 /* Module Parameters */
31 static int index = SNDRV_DEFAULT_IDX1;
32 static char *id = SNDRV_DEFAULT_STR1;
33 module_param(index, int, 0444);
34 MODULE_PARM_DESC(index, "Index value for SuperH DAC audio.");
35 module_param(id, charp, 0444);
36 MODULE_PARM_DESC(id, "ID string for SuperH DAC audio.");
37
38 /* main struct */
39 struct snd_sh_dac {
40         struct snd_card *card;
41         struct snd_pcm_substream *substream;
42         struct hrtimer hrtimer;
43         ktime_t wakeups_per_second;
44
45         int rate;
46         int empty;
47         char *data_buffer, *buffer_begin, *buffer_end;
48         int processed; /* bytes proccesed, to compare with period_size */
49         int buffer_size;
50         struct dac_audio_pdata *pdata;
51 };
52
53
54 static void dac_audio_start_timer(struct snd_sh_dac *chip)
55 {
56         hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
57                       HRTIMER_MODE_REL);
58 }
59
60 static void dac_audio_stop_timer(struct snd_sh_dac *chip)
61 {
62         hrtimer_cancel(&chip->hrtimer);
63 }
64
65 static void dac_audio_reset(struct snd_sh_dac *chip)
66 {
67         dac_audio_stop_timer(chip);
68         chip->buffer_begin = chip->buffer_end = chip->data_buffer;
69         chip->processed = 0;
70         chip->empty = 1;
71 }
72
73 static void dac_audio_set_rate(struct snd_sh_dac *chip)
74 {
75         chip->wakeups_per_second = 1000000000 / chip->rate;
76 }
77
78
79 /* PCM INTERFACE */
80
81 static const struct snd_pcm_hardware snd_sh_dac_pcm_hw = {
82         .info                   = (SNDRV_PCM_INFO_MMAP |
83                                         SNDRV_PCM_INFO_MMAP_VALID |
84                                         SNDRV_PCM_INFO_INTERLEAVED |
85                                         SNDRV_PCM_INFO_HALF_DUPLEX),
86         .formats                = SNDRV_PCM_FMTBIT_U8,
87         .rates                  = SNDRV_PCM_RATE_8000,
88         .rate_min               = 8000,
89         .rate_max               = 8000,
90         .channels_min           = 1,
91         .channels_max           = 1,
92         .buffer_bytes_max       = (48*1024),
93         .period_bytes_min       = 1,
94         .period_bytes_max       = (48*1024),
95         .periods_min            = 1,
96         .periods_max            = 1024,
97 };
98
99 static int snd_sh_dac_pcm_open(struct snd_pcm_substream *substream)
100 {
101         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
102         struct snd_pcm_runtime *runtime = substream->runtime;
103
104         runtime->hw = snd_sh_dac_pcm_hw;
105
106         chip->substream = substream;
107         chip->buffer_begin = chip->buffer_end = chip->data_buffer;
108         chip->processed = 0;
109         chip->empty = 1;
110
111         chip->pdata->start(chip->pdata);
112
113         return 0;
114 }
115
116 static int snd_sh_dac_pcm_close(struct snd_pcm_substream *substream)
117 {
118         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
119
120         chip->substream = NULL;
121
122         dac_audio_stop_timer(chip);
123         chip->pdata->stop(chip->pdata);
124
125         return 0;
126 }
127
128 static int snd_sh_dac_pcm_prepare(struct snd_pcm_substream *substream)
129 {
130         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
131         struct snd_pcm_runtime *runtime = chip->substream->runtime;
132
133         chip->buffer_size = runtime->buffer_size;
134         memset(chip->data_buffer, 0, chip->pdata->buffer_size);
135
136         return 0;
137 }
138
139 static int snd_sh_dac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
140 {
141         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
142
143         switch (cmd) {
144         case SNDRV_PCM_TRIGGER_START:
145                 dac_audio_start_timer(chip);
146                 break;
147         case SNDRV_PCM_TRIGGER_STOP:
148                 chip->buffer_begin = chip->buffer_end = chip->data_buffer;
149                 chip->processed = 0;
150                 chip->empty = 1;
151                 dac_audio_stop_timer(chip);
152                 break;
153         default:
154                  return -EINVAL;
155         }
156
157         return 0;
158 }
159
160 static int snd_sh_dac_pcm_copy(struct snd_pcm_substream *substream,
161                                int channel, unsigned long pos,
162                                void __user *src, unsigned long count)
163 {
164         /* channel is not used (interleaved data) */
165         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
166         struct snd_pcm_runtime *runtime = substream->runtime;
167
168         if (copy_from_user_toio(chip->data_buffer + pos, src, count))
169                 return -EFAULT;
170         chip->buffer_end = chip->data_buffer + pos + count;
171
172         if (chip->empty) {
173                 chip->empty = 0;
174                 dac_audio_start_timer(chip);
175         }
176
177         return 0;
178 }
179
180 static int snd_sh_dac_pcm_copy_kernel(struct snd_pcm_substream *substream,
181                                       int channel, unsigned long pos,
182                                       void *src, unsigned long count)
183 {
184         /* channel is not used (interleaved data) */
185         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
186         struct snd_pcm_runtime *runtime = substream->runtime;
187
188         memcpy_toio(chip->data_buffer + pos, src, count);
189         chip->buffer_end = chip->data_buffer + pos + count;
190
191         if (chip->empty) {
192                 chip->empty = 0;
193                 dac_audio_start_timer(chip);
194         }
195
196         return 0;
197 }
198
199 static int snd_sh_dac_pcm_silence(struct snd_pcm_substream *substream,
200                                   int channel, unsigned long pos,
201                                   unsigned long count)
202 {
203         /* channel is not used (interleaved data) */
204         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
205         struct snd_pcm_runtime *runtime = substream->runtime;
206
207         memset_io(chip->data_buffer + pos, 0, count);
208         chip->buffer_end = chip->data_buffer + pos + count;
209
210         if (chip->empty) {
211                 chip->empty = 0;
212                 dac_audio_start_timer(chip);
213         }
214
215         return 0;
216 }
217
218 static
219 snd_pcm_uframes_t snd_sh_dac_pcm_pointer(struct snd_pcm_substream *substream)
220 {
221         struct snd_sh_dac *chip = snd_pcm_substream_chip(substream);
222         int pointer = chip->buffer_begin - chip->data_buffer;
223
224         return pointer;
225 }
226
227 /* pcm ops */
228 static const struct snd_pcm_ops snd_sh_dac_pcm_ops = {
229         .open           = snd_sh_dac_pcm_open,
230         .close          = snd_sh_dac_pcm_close,
231         .prepare        = snd_sh_dac_pcm_prepare,
232         .trigger        = snd_sh_dac_pcm_trigger,
233         .pointer        = snd_sh_dac_pcm_pointer,
234         .copy_user      = snd_sh_dac_pcm_copy,
235         .copy_kernel    = snd_sh_dac_pcm_copy_kernel,
236         .fill_silence   = snd_sh_dac_pcm_silence,
237         .mmap           = snd_pcm_lib_mmap_iomem,
238 };
239
240 static int snd_sh_dac_pcm(struct snd_sh_dac *chip, int device)
241 {
242         int err;
243         struct snd_pcm *pcm;
244
245         /* device should be always 0 for us */
246         err = snd_pcm_new(chip->card, "SH_DAC PCM", device, 1, 0, &pcm);
247         if (err < 0)
248                 return err;
249
250         pcm->private_data = chip;
251         strcpy(pcm->name, "SH_DAC PCM");
252         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_sh_dac_pcm_ops);
253
254         /* buffer size=48K */
255         snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
256                                        NULL, 48 * 1024, 48 * 1024);
257
258         return 0;
259 }
260 /* END OF PCM INTERFACE */
261
262
263 /* driver .remove  --  destructor */
264 static int snd_sh_dac_remove(struct platform_device *devptr)
265 {
266         snd_card_free(platform_get_drvdata(devptr));
267         return 0;
268 }
269
270 /* free -- it has been defined by create */
271 static int snd_sh_dac_free(struct snd_sh_dac *chip)
272 {
273         /* release the data */
274         kfree(chip->data_buffer);
275         kfree(chip);
276
277         return 0;
278 }
279
280 static int snd_sh_dac_dev_free(struct snd_device *device)
281 {
282         struct snd_sh_dac *chip = device->device_data;
283
284         return snd_sh_dac_free(chip);
285 }
286
287 static enum hrtimer_restart sh_dac_audio_timer(struct hrtimer *handle)
288 {
289         struct snd_sh_dac *chip = container_of(handle, struct snd_sh_dac,
290                                                hrtimer);
291         struct snd_pcm_runtime *runtime = chip->substream->runtime;
292         ssize_t b_ps = frames_to_bytes(runtime, runtime->period_size);
293
294         if (!chip->empty) {
295                 sh_dac_output(*chip->buffer_begin, chip->pdata->channel);
296                 chip->buffer_begin++;
297
298                 chip->processed++;
299                 if (chip->processed >= b_ps) {
300                         chip->processed -= b_ps;
301                         snd_pcm_period_elapsed(chip->substream);
302                 }
303
304                 if (chip->buffer_begin == (chip->data_buffer +
305                                            chip->buffer_size - 1))
306                         chip->buffer_begin = chip->data_buffer;
307
308                 if (chip->buffer_begin == chip->buffer_end)
309                         chip->empty = 1;
310
311         }
312
313         if (!chip->empty)
314                 hrtimer_start(&chip->hrtimer, chip->wakeups_per_second,
315                               HRTIMER_MODE_REL);
316
317         return HRTIMER_NORESTART;
318 }
319
320 /* create  --  chip-specific constructor for the cards components */
321 static int snd_sh_dac_create(struct snd_card *card,
322                              struct platform_device *devptr,
323                              struct snd_sh_dac **rchip)
324 {
325         struct snd_sh_dac *chip;
326         int err;
327
328         static const struct snd_device_ops ops = {
329                    .dev_free = snd_sh_dac_dev_free,
330         };
331
332         *rchip = NULL;
333
334         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
335         if (chip == NULL)
336                 return -ENOMEM;
337
338         chip->card = card;
339
340         hrtimer_init(&chip->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
341         chip->hrtimer.function = sh_dac_audio_timer;
342
343         dac_audio_reset(chip);
344         chip->rate = 8000;
345         dac_audio_set_rate(chip);
346
347         chip->pdata = devptr->dev.platform_data;
348
349         chip->data_buffer = kmalloc(chip->pdata->buffer_size, GFP_KERNEL);
350         if (chip->data_buffer == NULL) {
351                 kfree(chip);
352                 return -ENOMEM;
353         }
354
355         err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
356         if (err < 0) {
357                 snd_sh_dac_free(chip);
358                 return err;
359         }
360
361         *rchip = chip;
362
363         return 0;
364 }
365
366 /* driver .probe  --  constructor */
367 static int snd_sh_dac_probe(struct platform_device *devptr)
368 {
369         struct snd_sh_dac *chip;
370         struct snd_card *card;
371         int err;
372
373         err = snd_card_new(&devptr->dev, index, id, THIS_MODULE, 0, &card);
374         if (err < 0) {
375                         snd_printk(KERN_ERR "cannot allocate the card\n");
376                         return err;
377         }
378
379         err = snd_sh_dac_create(card, devptr, &chip);
380         if (err < 0)
381                 goto probe_error;
382
383         err = snd_sh_dac_pcm(chip, 0);
384         if (err < 0)
385                 goto probe_error;
386
387         strcpy(card->driver, "snd_sh_dac");
388         strcpy(card->shortname, "SuperH DAC audio driver");
389         printk(KERN_INFO "%s %s", card->longname, card->shortname);
390
391         err = snd_card_register(card);
392         if (err < 0)
393                 goto probe_error;
394
395         snd_printk(KERN_INFO "ALSA driver for SuperH DAC audio");
396
397         platform_set_drvdata(devptr, card);
398         return 0;
399
400 probe_error:
401         snd_card_free(card);
402         return err;
403 }
404
405 /*
406  * "driver" definition
407  */
408 static struct platform_driver sh_dac_driver = {
409         .probe  = snd_sh_dac_probe,
410         .remove = snd_sh_dac_remove,
411         .driver = {
412                 .name = "dac_audio",
413         },
414 };
415
416 module_platform_driver(sh_dac_driver);