1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Au12x0/Au1550 PSC ALSA ASoC audio support.
4 *
5 * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
6 * Manuel Lauss <manuel.lauss@gmail.com>
7 *
8 * DMA glue for Au1x-PSC audio.
9 */
10
11
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/dma-mapping.h>
17
18 #include <sound/core.h>
19 #include <sound/pcm.h>
20 #include <sound/pcm_params.h>
21 #include <sound/soc.h>
22
23 #include <asm/mach-au1x00/au1000.h>
24 #include <asm/mach-au1x00/au1xxx_dbdma.h>
25 #include <asm/mach-au1x00/au1xxx_psc.h>
26
27 #include "psc.h"
28
29 /*#define PCM_DEBUG*/
30
31 #define DRV_NAME "dbdma2"
32
33 #define MSG(x...) printk(KERN_INFO "au1xpsc_pcm: " x)
34 #ifdef PCM_DEBUG
35 #define DBG MSG
36 #else
37 #define DBG(x...) do {} while (0)
38 #endif
39
40 struct au1xpsc_audio_dmadata {
41 /* DDMA control data */
42 unsigned int ddma_id; /* DDMA direction ID for this PSC */
43 u32 ddma_chan; /* DDMA context */
44
45 /* PCM context (for irq handlers) */
46 struct snd_pcm_substream *substream;
47 unsigned long curr_period; /* current segment DDMA is working on */
48 unsigned long q_period; /* queue period(s) */
49 dma_addr_t dma_area; /* address of queued DMA area */
50 dma_addr_t dma_area_s; /* start address of DMA area */
51 unsigned long pos; /* current byte position being played */
52 unsigned long periods; /* number of SG segments in total */
53 unsigned long period_bytes; /* size in bytes of one SG segment */
54
55 /* runtime data */
56 int msbits;
57 };
58
59 /*
60 * These settings are somewhat okay, at least on my machine audio plays
61 * almost skip-free. Especially the 64kB buffer seems to help a LOT.
62 */
63 #define AU1XPSC_PERIOD_MIN_BYTES 1024
64 #define AU1XPSC_BUFFER_MIN_BYTES 65536
65
66 /* PCM hardware DMA capabilities - platform specific */
67 static const struct snd_pcm_hardware au1xpsc_pcm_hardware = {
68 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
69 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
70 .period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES,
71 .period_bytes_max = 4096 * 1024 - 1,
72 .periods_min = 2,
73 .periods_max = 4096, /* 2 to as-much-as-you-like */
74 .buffer_bytes_max = 4096 * 1024 - 1,
75 .fifo_size = 16, /* fifo entries of AC97/I2S PSC */
76 };
77
78 static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd)
79 {
80 au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area,
81 cd->period_bytes, DDMA_FLAGS_IE);
82
83 /* update next-to-queue period */
84 ++cd->q_period;
85 cd->dma_area += cd->period_bytes;
86 if (cd->q_period >= cd->periods) {
87 cd->q_period = 0;
88 cd->dma_area = cd->dma_area_s;
89 }
90 }
91
92 static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd)
93 {
94 au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area,
95 cd->period_bytes, DDMA_FLAGS_IE);
96
97 /* update next-to-queue period */
98 ++cd->q_period;
99 cd->dma_area += cd->period_bytes;
100 if (cd->q_period >= cd->periods) {
101 cd->q_period = 0;
102 cd->dma_area = cd->dma_area_s;
103 }
104 }
105
106 static void au1x_pcm_dmatx_cb(int irq, void *dev_id)
107 {
108 struct au1xpsc_audio_dmadata *cd = dev_id;
109
110 cd->pos += cd->period_bytes;
111 if (++cd->curr_period >= cd->periods) {
112 cd->pos = 0;
113 cd->curr_period = 0;
114 }
115 snd_pcm_period_elapsed(cd->substream);
116 au1x_pcm_queue_tx(cd);
117 }
118
119 static void au1x_pcm_dmarx_cb(int irq, void *dev_id)
120 {
121 struct au1xpsc_audio_dmadata *cd = dev_id;
122
123 cd->pos += cd->period_bytes;
124 if (++cd->curr_period >= cd->periods) {
125 cd->pos = 0;
126 cd->curr_period = 0;
127 }
128 snd_pcm_period_elapsed(cd->substream);
129 au1x_pcm_queue_rx(cd);
130 }
131
132 static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd)
133 {
134 if (pcd->ddma_chan) {
135 au1xxx_dbdma_stop(pcd->ddma_chan);
136 au1xxx_dbdma_reset(pcd->ddma_chan);
137 au1xxx_dbdma_chan_free(pcd->ddma_chan);
138 pcd->ddma_chan = 0;
139 pcd->msbits = 0;
140 }
141 }
142
143 /* in case of missing DMA ring or changed TX-source / RX-dest bit widths,
144 * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according
145 * to ALSA-supplied sample depth. This is due to limitations in the dbdma api
146 * (cannot adjust source/dest widths of already allocated descriptor ring).
147 */
148 static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd,
149 int stype, int msbits)
150 {
151 /* DMA only in 8/16/32 bit widths */
152 if (msbits == 24)
153 msbits = 32;
154
155 /* check current config: correct bits and descriptors allocated? */
156 if ((pcd->ddma_chan) && (msbits == pcd->msbits))
157 goto out; /* all ok! */
158
159 au1x_pcm_dbdma_free(pcd);
160
161 if (stype == SNDRV_PCM_STREAM_CAPTURE)
162 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id,
163 DSCR_CMD0_ALWAYS,
164 au1x_pcm_dmarx_cb, (void *)pcd);
165 else
166 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS,
167 pcd->ddma_id,
168 au1x_pcm_dmatx_cb, (void *)pcd);
169
170 if (!pcd->ddma_chan)
171 return -ENOMEM;
172
173 au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits);
174 au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2);
175
176 pcd->msbits = msbits;
177
178 au1xxx_dbdma_stop(pcd->ddma_chan);
179 au1xxx_dbdma_reset(pcd->ddma_chan);
180
181 out:
182 return 0;
183 }
184
185 static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss,
186 struct snd_soc_component *component)
187 {
188 struct au1xpsc_audio_dmadata *pcd = snd_soc_component_get_drvdata(component);
189 return &pcd[ss->stream];
190 }
191
192 static int au1xpsc_pcm_hw_params(struct snd_soc_component *component,
193 struct snd_pcm_substream *substream,
194 struct snd_pcm_hw_params *params)
195 {
196 struct snd_pcm_runtime *runtime = substream->runtime;
197 struct au1xpsc_audio_dmadata *pcd;
198 int stype, ret;
199
200 stype = substream->stream;
201 pcd = to_dmadata(substream, component);
202
203 DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %zu "
204 "runtime->min_align %lu\n",
205 (unsigned long)runtime->dma_area,
206 (unsigned long)runtime->dma_addr, runtime->dma_bytes,
207 runtime->min_align);
208
209 DBG("bits %d frags %d frag_bytes %d is_rx %d\n", params->msbits,
210 params_periods(params), params_period_bytes(params), stype);
211
212 ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits);
213 if (ret) {
214 MSG("DDMA channel (re)alloc failed!\n");
215 goto out;
216 }
217
218 pcd->substream = substream;
219 pcd->period_bytes = params_period_bytes(params);
220 pcd->periods = params_periods(params);
221 pcd->dma_area_s = pcd->dma_area = runtime->dma_addr;
222 pcd->q_period = 0;
223 pcd->curr_period = 0;
224 pcd->pos = 0;
225
226 ret = 0;
227 out:
228 return ret;
229 }
230
231 static int au1xpsc_pcm_prepare(struct snd_soc_component *component,
232 struct snd_pcm_substream *substream)
233 {
234 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);
235
236 au1xxx_dbdma_reset(pcd->ddma_chan);
237
238 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
239 au1x_pcm_queue_rx(pcd);
240 au1x_pcm_queue_rx(pcd);
241 } else {
242 au1x_pcm_queue_tx(pcd);
243 au1x_pcm_queue_tx(pcd);
244 }
245
246 return 0;
247 }
248
249 static int au1xpsc_pcm_trigger(struct snd_soc_component *component,
250 struct snd_pcm_substream *substream, int cmd)
251 {
252 u32 c = to_dmadata(substream, component)->ddma_chan;
253
254 switch (cmd) {
255 case SNDRV_PCM_TRIGGER_START:
256 case SNDRV_PCM_TRIGGER_RESUME:
257 au1xxx_dbdma_start(c);
258 break;
259 case SNDRV_PCM_TRIGGER_STOP:
260 case SNDRV_PCM_TRIGGER_SUSPEND:
261 au1xxx_dbdma_stop(c);
262 break;
263 default:
264 return -EINVAL;
265 }
266 return 0;
267 }
268
269 static snd_pcm_uframes_t
270 au1xpsc_pcm_pointer(struct snd_soc_component *component,
271 struct snd_pcm_substream *substream)
272 {
273 return bytes_to_frames(substream->runtime,
274 to_dmadata(substream, component)->pos);
275 }
276
277 static int au1xpsc_pcm_open(struct snd_soc_component *component,
278 struct snd_pcm_substream *substream)
279 {
280 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);
281 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
282 int stype = substream->stream, *dmaids;
283
284 dmaids = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
285 if (!dmaids)
286 return -ENODEV; /* whoa, has ordering changed? */
287
288 pcd->ddma_id = dmaids[stype];
289
290 snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware);
291 return 0;
292 }
293
294 static int au1xpsc_pcm_close(struct snd_soc_component *component,
295 struct snd_pcm_substream *substream)
296 {
297 au1x_pcm_dbdma_free(to_dmadata(substream, component));
298 return 0;
299 }
300
301 static int au1xpsc_pcm_new(struct snd_soc_component *component,
302 struct snd_soc_pcm_runtime *rtd)
303 {
304 struct snd_card *card = rtd->card->snd_card;
305 struct snd_pcm *pcm = rtd->pcm;
306
307 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
308 card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);
309
310 return 0;
311 }
312
313 /* au1xpsc audio platform */
314 static struct snd_soc_component_driver au1xpsc_soc_component = {
315 .name = DRV_NAME,
316 .open = au1xpsc_pcm_open,
317 .close = au1xpsc_pcm_close,
318 .hw_params = au1xpsc_pcm_hw_params,
319 .prepare = au1xpsc_pcm_prepare,
320 .trigger = au1xpsc_pcm_trigger,
321 .pointer = au1xpsc_pcm_pointer,
322 .pcm_construct = au1xpsc_pcm_new,
323 };
324
325 static int au1xpsc_pcm_drvprobe(struct platform_device *pdev)
326 {
327 struct au1xpsc_audio_dmadata *dmadata;
328
329 dmadata = devm_kcalloc(&pdev->dev,
330 2, sizeof(struct au1xpsc_audio_dmadata),
331 GFP_KERNEL);
332 if (!dmadata)
333 return -ENOMEM;
334
335 platform_set_drvdata(pdev, dmadata);
336
337 return devm_snd_soc_register_component(&pdev->dev,
338 &au1xpsc_soc_component, NULL, 0);
339 }
340
341 static struct platform_driver au1xpsc_pcm_driver = {
342 .driver = {
343 .name = "au1xpsc-pcm",
344 },
345 .probe = au1xpsc_pcm_drvprobe,
346 };
347
348 module_platform_driver(au1xpsc_pcm_driver);
349
350 MODULE_LICENSE("GPL");
351 MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
352 MODULE_AUTHOR("Manuel Lauss");
353
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