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