1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 VanguardiaSur - www.vanguardiasur.com.ar
4  *
5  * Based on the audio support from the tw6869 driver:
6  * Copyright 2015 www.starterkit.ru <info@starterkit.ru>
7  *
8  * Based on:
9  * Driver for Intersil|Techwell TW6869 based DVR cards
10  * (c) 2011-12 liran <jli11@intersil.com> [Intersil|Techwell China]
11  */
12 
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/kmod.h>
18 #include <linux/mutex.h>
19 #include <linux/pci.h>
20 #include <linux/delay.h>
21 
22 #include <sound/core.h>
23 #include <sound/initval.h>
24 #include <sound/pcm.h>
25 #include <sound/control.h>
26 #include "tw686x.h"
27 #include "tw686x-regs.h"
28 
29 #define AUDIO_CHANNEL_OFFSET 8
30 
tw686x_audio_irq(struct tw686x_dev * dev,unsigned long requests,unsigned int pb_status)31 void tw686x_audio_irq(struct tw686x_dev *dev, unsigned long requests,
32 		      unsigned int pb_status)
33 {
34 	unsigned long flags;
35 	unsigned int ch, pb;
36 
37 	for_each_set_bit(ch, &requests, max_channels(dev)) {
38 		struct tw686x_audio_channel *ac = &dev->audio_channels[ch];
39 		struct tw686x_audio_buf *done = NULL;
40 		struct tw686x_audio_buf *next = NULL;
41 		struct tw686x_dma_desc *desc;
42 
43 		pb = !!(pb_status & BIT(AUDIO_CHANNEL_OFFSET + ch));
44 
45 		spin_lock_irqsave(&ac->lock, flags);
46 
47 		/* Sanity check */
48 		if (!ac->ss || !ac->curr_bufs[0] || !ac->curr_bufs[1]) {
49 			spin_unlock_irqrestore(&ac->lock, flags);
50 			continue;
51 		}
52 
53 		if (!list_empty(&ac->buf_list)) {
54 			next = list_first_entry(&ac->buf_list,
55 					struct tw686x_audio_buf, list);
56 			list_move_tail(&next->list, &ac->buf_list);
57 			done = ac->curr_bufs[!pb];
58 			ac->curr_bufs[pb] = next;
59 		}
60 		spin_unlock_irqrestore(&ac->lock, flags);
61 
62 		if (!done || !next)
63 			continue;
64 		/*
65 		 * Checking for a non-nil dma_desc[pb]->virt buffer is
66 		 * the same as checking for memcpy DMA mode.
67 		 */
68 		desc = &ac->dma_descs[pb];
69 		if (desc->virt) {
70 			memcpy(done->virt, desc->virt,
71 			       dev->period_size);
72 		} else {
73 			u32 reg = pb ? ADMA_B_ADDR[ch] : ADMA_P_ADDR[ch];
74 			reg_write(dev, reg, next->dma);
75 		}
76 		ac->ptr = done->dma - ac->buf[0].dma;
77 		snd_pcm_period_elapsed(ac->ss);
78 	}
79 }
80 
81 /*
82  * Audio parameters are global and shared among all
83  * capture channels. The driver prevents changes to
84  * the parameters if any audio channel is capturing.
85  */
86 static const struct snd_pcm_hardware tw686x_capture_hw = {
87 	.info			= (SNDRV_PCM_INFO_MMAP |
88 				   SNDRV_PCM_INFO_INTERLEAVED |
89 				   SNDRV_PCM_INFO_BLOCK_TRANSFER |
90 				   SNDRV_PCM_INFO_MMAP_VALID),
91 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
92 	.rates			= SNDRV_PCM_RATE_8000_48000,
93 	.rate_min		= 8000,
94 	.rate_max		= 48000,
95 	.channels_min		= 1,
96 	.channels_max		= 1,
97 	.buffer_bytes_max	= TW686X_AUDIO_PAGE_MAX * AUDIO_DMA_SIZE_MAX,
98 	.period_bytes_min	= AUDIO_DMA_SIZE_MIN,
99 	.period_bytes_max	= AUDIO_DMA_SIZE_MAX,
100 	.periods_min		= TW686X_AUDIO_PERIODS_MIN,
101 	.periods_max		= TW686X_AUDIO_PERIODS_MAX,
102 };
103 
tw686x_pcm_open(struct snd_pcm_substream * ss)104 static int tw686x_pcm_open(struct snd_pcm_substream *ss)
105 {
106 	struct tw686x_dev *dev = snd_pcm_substream_chip(ss);
107 	struct tw686x_audio_channel *ac = &dev->audio_channels[ss->number];
108 	struct snd_pcm_runtime *rt = ss->runtime;
109 	int err;
110 
111 	ac->ss = ss;
112 	rt->hw = tw686x_capture_hw;
113 
114 	err = snd_pcm_hw_constraint_integer(rt, SNDRV_PCM_HW_PARAM_PERIODS);
115 	if (err < 0)
116 		return err;
117 
118 	return 0;
119 }
120 
tw686x_pcm_close(struct snd_pcm_substream * ss)121 static int tw686x_pcm_close(struct snd_pcm_substream *ss)
122 {
123 	struct tw686x_dev *dev = snd_pcm_substream_chip(ss);
124 	struct tw686x_audio_channel *ac = &dev->audio_channels[ss->number];
125 
126 	ac->ss = NULL;
127 	return 0;
128 }
129 
tw686x_pcm_prepare(struct snd_pcm_substream * ss)130 static int tw686x_pcm_prepare(struct snd_pcm_substream *ss)
131 {
132 	struct tw686x_dev *dev = snd_pcm_substream_chip(ss);
133 	struct tw686x_audio_channel *ac = &dev->audio_channels[ss->number];
134 	struct snd_pcm_runtime *rt = ss->runtime;
135 	unsigned int period_size = snd_pcm_lib_period_bytes(ss);
136 	struct tw686x_audio_buf *p_buf, *b_buf;
137 	unsigned long flags;
138 	int i;
139 
140 	spin_lock_irqsave(&dev->lock, flags);
141 	/*
142 	 * Given the audio parameters are global (i.e. shared across
143 	 * DMA channels), we need to check new params are allowed.
144 	 */
145 	if (((dev->audio_rate != rt->rate) ||
146 	     (dev->period_size != period_size)) && dev->audio_enabled)
147 		goto err_audio_busy;
148 
149 	tw686x_disable_channel(dev, AUDIO_CHANNEL_OFFSET + ac->ch);
150 	spin_unlock_irqrestore(&dev->lock, flags);
151 
152 	if (dev->audio_rate != rt->rate) {
153 		u32 reg;
154 
155 		dev->audio_rate = rt->rate;
156 		reg = ((125000000 / rt->rate) << 16) +
157 		       ((125000000 % rt->rate) << 16) / rt->rate;
158 
159 		reg_write(dev, AUDIO_CONTROL2, reg);
160 	}
161 
162 	if (dev->period_size != period_size) {
163 		u32 reg;
164 
165 		dev->period_size = period_size;
166 		reg = reg_read(dev, AUDIO_CONTROL1);
167 		reg &= ~(AUDIO_DMA_SIZE_MASK << AUDIO_DMA_SIZE_SHIFT);
168 		reg |= period_size << AUDIO_DMA_SIZE_SHIFT;
169 
170 		reg_write(dev, AUDIO_CONTROL1, reg);
171 	}
172 
173 	if (rt->periods < TW686X_AUDIO_PERIODS_MIN ||
174 	    rt->periods > TW686X_AUDIO_PERIODS_MAX)
175 		return -EINVAL;
176 
177 	spin_lock_irqsave(&ac->lock, flags);
178 	INIT_LIST_HEAD(&ac->buf_list);
179 
180 	for (i = 0; i < rt->periods; i++) {
181 		ac->buf[i].dma = rt->dma_addr + period_size * i;
182 		ac->buf[i].virt = rt->dma_area + period_size * i;
183 		INIT_LIST_HEAD(&ac->buf[i].list);
184 		list_add_tail(&ac->buf[i].list, &ac->buf_list);
185 	}
186 
187 	p_buf =	list_first_entry(&ac->buf_list, struct tw686x_audio_buf, list);
188 	list_move_tail(&p_buf->list, &ac->buf_list);
189 
190 	b_buf =	list_first_entry(&ac->buf_list, struct tw686x_audio_buf, list);
191 	list_move_tail(&b_buf->list, &ac->buf_list);
192 
193 	ac->curr_bufs[0] = p_buf;
194 	ac->curr_bufs[1] = b_buf;
195 	ac->ptr = 0;
196 
197 	if (dev->dma_mode != TW686X_DMA_MODE_MEMCPY) {
198 		reg_write(dev, ADMA_P_ADDR[ac->ch], p_buf->dma);
199 		reg_write(dev, ADMA_B_ADDR[ac->ch], b_buf->dma);
200 	}
201 
202 	spin_unlock_irqrestore(&ac->lock, flags);
203 
204 	return 0;
205 
206 err_audio_busy:
207 	spin_unlock_irqrestore(&dev->lock, flags);
208 	return -EBUSY;
209 }
210 
tw686x_pcm_trigger(struct snd_pcm_substream * ss,int cmd)211 static int tw686x_pcm_trigger(struct snd_pcm_substream *ss, int cmd)
212 {
213 	struct tw686x_dev *dev = snd_pcm_substream_chip(ss);
214 	struct tw686x_audio_channel *ac = &dev->audio_channels[ss->number];
215 	unsigned long flags;
216 	int err = 0;
217 
218 	switch (cmd) {
219 	case SNDRV_PCM_TRIGGER_START:
220 		if (ac->curr_bufs[0] && ac->curr_bufs[1]) {
221 			spin_lock_irqsave(&dev->lock, flags);
222 			dev->audio_enabled = 1;
223 			tw686x_enable_channel(dev,
224 				AUDIO_CHANNEL_OFFSET + ac->ch);
225 			spin_unlock_irqrestore(&dev->lock, flags);
226 
227 			mod_timer(&dev->dma_delay_timer,
228 				  jiffies + msecs_to_jiffies(100));
229 		} else {
230 			err = -EIO;
231 		}
232 		break;
233 	case SNDRV_PCM_TRIGGER_STOP:
234 		spin_lock_irqsave(&dev->lock, flags);
235 		dev->audio_enabled = 0;
236 		tw686x_disable_channel(dev, AUDIO_CHANNEL_OFFSET + ac->ch);
237 		spin_unlock_irqrestore(&dev->lock, flags);
238 
239 		spin_lock_irqsave(&ac->lock, flags);
240 		ac->curr_bufs[0] = NULL;
241 		ac->curr_bufs[1] = NULL;
242 		spin_unlock_irqrestore(&ac->lock, flags);
243 		break;
244 	default:
245 		err = -EINVAL;
246 	}
247 	return err;
248 }
249 
tw686x_pcm_pointer(struct snd_pcm_substream * ss)250 static snd_pcm_uframes_t tw686x_pcm_pointer(struct snd_pcm_substream *ss)
251 {
252 	struct tw686x_dev *dev = snd_pcm_substream_chip(ss);
253 	struct tw686x_audio_channel *ac = &dev->audio_channels[ss->number];
254 
255 	return bytes_to_frames(ss->runtime, ac->ptr);
256 }
257 
258 static const struct snd_pcm_ops tw686x_pcm_ops = {
259 	.open = tw686x_pcm_open,
260 	.close = tw686x_pcm_close,
261 	.prepare = tw686x_pcm_prepare,
262 	.trigger = tw686x_pcm_trigger,
263 	.pointer = tw686x_pcm_pointer,
264 };
265 
tw686x_snd_pcm_init(struct tw686x_dev * dev)266 static int tw686x_snd_pcm_init(struct tw686x_dev *dev)
267 {
268 	struct snd_card *card = dev->snd_card;
269 	struct snd_pcm *pcm;
270 	struct snd_pcm_substream *ss;
271 	unsigned int i;
272 	int err;
273 
274 	err = snd_pcm_new(card, card->driver, 0, 0, max_channels(dev), &pcm);
275 	if (err < 0)
276 		return err;
277 
278 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &tw686x_pcm_ops);
279 	snd_pcm_chip(pcm) = dev;
280 	pcm->info_flags = 0;
281 	strscpy(pcm->name, "tw686x PCM", sizeof(pcm->name));
282 
283 	for (i = 0, ss = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
284 	     ss; ss = ss->next, i++)
285 		snprintf(ss->name, sizeof(ss->name), "vch%u audio", i);
286 
287 	snd_pcm_set_managed_buffer_all(pcm,
288 				SNDRV_DMA_TYPE_DEV,
289 				&dev->pci_dev->dev,
290 				TW686X_AUDIO_PAGE_MAX * AUDIO_DMA_SIZE_MAX,
291 				TW686X_AUDIO_PAGE_MAX * AUDIO_DMA_SIZE_MAX);
292 	return 0;
293 }
294 
tw686x_audio_dma_free(struct tw686x_dev * dev,struct tw686x_audio_channel * ac)295 static void tw686x_audio_dma_free(struct tw686x_dev *dev,
296 				  struct tw686x_audio_channel *ac)
297 {
298 	int pb;
299 
300 	for (pb = 0; pb < 2; pb++) {
301 		if (!ac->dma_descs[pb].virt)
302 			continue;
303 		dma_free_coherent(&dev->pci_dev->dev, ac->dma_descs[pb].size,
304 				  ac->dma_descs[pb].virt,
305 				  ac->dma_descs[pb].phys);
306 		ac->dma_descs[pb].virt = NULL;
307 	}
308 }
309 
tw686x_audio_dma_alloc(struct tw686x_dev * dev,struct tw686x_audio_channel * ac)310 static int tw686x_audio_dma_alloc(struct tw686x_dev *dev,
311 				  struct tw686x_audio_channel *ac)
312 {
313 	int pb;
314 
315 	/*
316 	 * In the memcpy DMA mode we allocate a coherent buffer
317 	 * and use it for the DMA capture. Otherwise, DMA
318 	 * acts on the ALSA buffers as received in pcm_prepare.
319 	 */
320 	if (dev->dma_mode != TW686X_DMA_MODE_MEMCPY)
321 		return 0;
322 
323 	for (pb = 0; pb < 2; pb++) {
324 		u32 reg = pb ? ADMA_B_ADDR[ac->ch] : ADMA_P_ADDR[ac->ch];
325 		void *virt;
326 
327 		virt = dma_alloc_coherent(&dev->pci_dev->dev,
328 					  AUDIO_DMA_SIZE_MAX,
329 					  &ac->dma_descs[pb].phys, GFP_KERNEL);
330 		if (!virt) {
331 			dev_err(&dev->pci_dev->dev,
332 				"dma%d: unable to allocate audio DMA %s-buffer\n",
333 				ac->ch, pb ? "B" : "P");
334 			return -ENOMEM;
335 		}
336 		ac->dma_descs[pb].virt = virt;
337 		ac->dma_descs[pb].size = AUDIO_DMA_SIZE_MAX;
338 		reg_write(dev, reg, ac->dma_descs[pb].phys);
339 	}
340 	return 0;
341 }
342 
tw686x_audio_free(struct tw686x_dev * dev)343 void tw686x_audio_free(struct tw686x_dev *dev)
344 {
345 	unsigned long flags;
346 	u32 dma_ch_mask;
347 	u32 dma_cmd;
348 
349 	spin_lock_irqsave(&dev->lock, flags);
350 	dma_cmd = reg_read(dev, DMA_CMD);
351 	dma_ch_mask = reg_read(dev, DMA_CHANNEL_ENABLE);
352 	reg_write(dev, DMA_CMD, dma_cmd & ~0xff00);
353 	reg_write(dev, DMA_CHANNEL_ENABLE, dma_ch_mask & ~0xff00);
354 	spin_unlock_irqrestore(&dev->lock, flags);
355 
356 	if (!dev->snd_card)
357 		return;
358 	snd_card_free(dev->snd_card);
359 	dev->snd_card = NULL;
360 }
361 
tw686x_audio_init(struct tw686x_dev * dev)362 int tw686x_audio_init(struct tw686x_dev *dev)
363 {
364 	struct pci_dev *pci_dev = dev->pci_dev;
365 	struct snd_card *card;
366 	int err, ch;
367 
368 	/* Enable external audio */
369 	reg_write(dev, AUDIO_CONTROL1, BIT(0));
370 
371 	err = snd_card_new(&pci_dev->dev, SNDRV_DEFAULT_IDX1,
372 			   SNDRV_DEFAULT_STR1,
373 			   THIS_MODULE, 0, &card);
374 	if (err < 0)
375 		return err;
376 
377 	dev->snd_card = card;
378 	strscpy(card->driver, "tw686x", sizeof(card->driver));
379 	strscpy(card->shortname, "tw686x", sizeof(card->shortname));
380 	strscpy(card->longname, pci_name(pci_dev), sizeof(card->longname));
381 	snd_card_set_dev(card, &pci_dev->dev);
382 
383 	for (ch = 0; ch < max_channels(dev); ch++) {
384 		struct tw686x_audio_channel *ac;
385 
386 		ac = &dev->audio_channels[ch];
387 		spin_lock_init(&ac->lock);
388 		ac->dev = dev;
389 		ac->ch = ch;
390 
391 		err = tw686x_audio_dma_alloc(dev, ac);
392 		if (err < 0)
393 			goto err_cleanup;
394 	}
395 
396 	err = tw686x_snd_pcm_init(dev);
397 	if (err < 0)
398 		goto err_cleanup;
399 
400 	err = snd_card_register(card);
401 	if (!err)
402 		return 0;
403 
404 err_cleanup:
405 	for (ch = 0; ch < max_channels(dev); ch++) {
406 		if (!dev->audio_channels[ch].dev)
407 			continue;
408 		tw686x_audio_dma_free(dev, &dev->audio_channels[ch]);
409 	}
410 	snd_card_free(card);
411 	dev->snd_card = NULL;
412 	return err;
413 }
414