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14#include <linux/io.h>
15#include <linux/rcupdate.h>
16#include <sound/pcm.h>
17#include <sound/pcm_params.h>
18#include "local.h"
19
20#define BUFFER_BYTES_MAX (3 * 2 * 8 * PERIOD_BYTES_MIN)
21#define PERIOD_BYTES_MIN 4096
22#define PERIODS_MIN 2
23
24#define dw_pcm_tx_fn(sample_bits) \
25static unsigned int dw_pcm_tx_##sample_bits(struct dw_i2s_dev *dev, \
26 struct snd_pcm_runtime *runtime, unsigned int tx_ptr, \
27 bool *period_elapsed) \
28{ \
29 const u##sample_bits (*p)[2] = (void *)runtime->dma_area; \
30 unsigned int period_pos = tx_ptr % runtime->period_size; \
31 int i; \
32\
33 for (i = 0; i < dev->fifo_th; i++) { \
34 iowrite32(p[tx_ptr][0], dev->i2s_base + LRBR_LTHR(0)); \
35 iowrite32(p[tx_ptr][1], dev->i2s_base + RRBR_RTHR(0)); \
36 period_pos++; \
37 if (++tx_ptr >= runtime->buffer_size) \
38 tx_ptr = 0; \
39 } \
40 *period_elapsed = period_pos >= runtime->period_size; \
41 return tx_ptr; \
42}
43
44#define dw_pcm_rx_fn(sample_bits) \
45static unsigned int dw_pcm_rx_##sample_bits(struct dw_i2s_dev *dev, \
46 struct snd_pcm_runtime *runtime, unsigned int rx_ptr, \
47 bool *period_elapsed) \
48{ \
49 u##sample_bits (*p)[2] = (void *)runtime->dma_area; \
50 unsigned int period_pos = rx_ptr % runtime->period_size; \
51 int i; \
52\
53 for (i = 0; i < dev->fifo_th; i++) { \
54 p[rx_ptr][0] = ioread32(dev->i2s_base + LRBR_LTHR(0)); \
55 p[rx_ptr][1] = ioread32(dev->i2s_base + RRBR_RTHR(0)); \
56 period_pos++; \
57 if (++rx_ptr >= runtime->buffer_size) \
58 rx_ptr = 0; \
59 } \
60 *period_elapsed = period_pos >= runtime->period_size; \
61 return rx_ptr; \
62}
63
64dw_pcm_tx_fn(16);
65dw_pcm_tx_fn(32);
66dw_pcm_rx_fn(16);
67dw_pcm_rx_fn(32);
68
69#undef dw_pcm_tx_fn
70#undef dw_pcm_rx_fn
71
72static const struct snd_pcm_hardware dw_pcm_hardware = {
73 .info = SNDRV_PCM_INFO_INTERLEAVED |
74 SNDRV_PCM_INFO_MMAP |
75 SNDRV_PCM_INFO_MMAP_VALID |
76 SNDRV_PCM_INFO_BLOCK_TRANSFER,
77 .rates = SNDRV_PCM_RATE_32000 |
78 SNDRV_PCM_RATE_44100 |
79 SNDRV_PCM_RATE_48000,
80 .rate_min = 32000,
81 .rate_max = 48000,
82 .formats = SNDRV_PCM_FMTBIT_S16_LE |
83 SNDRV_PCM_FMTBIT_S24_LE |
84 SNDRV_PCM_FMTBIT_S32_LE,
85 .channels_min = 2,
86 .channels_max = 2,
87 .buffer_bytes_max = BUFFER_BYTES_MAX,
88 .period_bytes_min = PERIOD_BYTES_MIN,
89 .period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN,
90 .periods_min = PERIODS_MIN,
91 .periods_max = BUFFER_BYTES_MAX / PERIOD_BYTES_MIN,
92 .fifo_size = 16,
93};
94
95static void dw_pcm_transfer(struct dw_i2s_dev *dev, bool push)
96{
97 struct snd_pcm_substream *substream;
98 bool active, period_elapsed;
99
100 rcu_read_lock();
101 if (push)
102 substream = rcu_dereference(dev->tx_substream);
103 else
104 substream = rcu_dereference(dev->rx_substream);
105 active = substream && snd_pcm_running(substream);
106 if (active) {
107 unsigned int ptr;
108 unsigned int new_ptr;
109
110 if (push) {
111 ptr = READ_ONCE(dev->tx_ptr);
112 new_ptr = dev->tx_fn(dev, substream->runtime, ptr,
113 &period_elapsed);
114 cmpxchg(&dev->tx_ptr, ptr, new_ptr);
115 } else {
116 ptr = READ_ONCE(dev->rx_ptr);
117 new_ptr = dev->rx_fn(dev, substream->runtime, ptr,
118 &period_elapsed);
119 cmpxchg(&dev->rx_ptr, ptr, new_ptr);
120 }
121
122 if (period_elapsed)
123 snd_pcm_period_elapsed(substream);
124 }
125 rcu_read_unlock();
126}
127
128void dw_pcm_push_tx(struct dw_i2s_dev *dev)
129{
130 dw_pcm_transfer(dev, true);
131}
132
133void dw_pcm_pop_rx(struct dw_i2s_dev *dev)
134{
135 dw_pcm_transfer(dev, false);
136}
137
138static int dw_pcm_open(struct snd_pcm_substream *substream)
139{
140 struct snd_pcm_runtime *runtime = substream->runtime;
141 struct snd_soc_pcm_runtime *rtd = substream->private_data;
142 struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(rtd->cpu_dai);
143
144 snd_soc_set_runtime_hwparams(substream, &dw_pcm_hardware);
145 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
146 runtime->private_data = dev;
147
148 return 0;
149}
150
151static int dw_pcm_close(struct snd_pcm_substream *substream)
152{
153 synchronize_rcu();
154 return 0;
155}
156
157static int dw_pcm_hw_params(struct snd_pcm_substream *substream,
158 struct snd_pcm_hw_params *hw_params)
159{
160 struct snd_pcm_runtime *runtime = substream->runtime;
161 struct dw_i2s_dev *dev = runtime->private_data;
162 int ret;
163
164 switch (params_channels(hw_params)) {
165 case 2:
166 break;
167 default:
168 dev_err(dev->dev, "invalid channels number\n");
169 return -EINVAL;
170 }
171
172 switch (params_format(hw_params)) {
173 case SNDRV_PCM_FORMAT_S16_LE:
174 dev->tx_fn = dw_pcm_tx_16;
175 dev->rx_fn = dw_pcm_rx_16;
176 break;
177 case SNDRV_PCM_FORMAT_S24_LE:
178 case SNDRV_PCM_FORMAT_S32_LE:
179 dev->tx_fn = dw_pcm_tx_32;
180 dev->rx_fn = dw_pcm_rx_32;
181 break;
182 default:
183 dev_err(dev->dev, "invalid format\n");
184 return -EINVAL;
185 }
186
187 ret = snd_pcm_lib_malloc_pages(substream,
188 params_buffer_bytes(hw_params));
189 if (ret < 0)
190 return ret;
191 else
192 return 0;
193}
194
195static int dw_pcm_hw_free(struct snd_pcm_substream *substream)
196{
197 return snd_pcm_lib_free_pages(substream);
198}
199
200static int dw_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
201{
202 struct snd_pcm_runtime *runtime = substream->runtime;
203 struct dw_i2s_dev *dev = runtime->private_data;
204 int ret = 0;
205
206 switch (cmd) {
207 case SNDRV_PCM_TRIGGER_START:
208 case SNDRV_PCM_TRIGGER_RESUME:
209 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
210 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
211 WRITE_ONCE(dev->tx_ptr, 0);
212 rcu_assign_pointer(dev->tx_substream, substream);
213 } else {
214 WRITE_ONCE(dev->rx_ptr, 0);
215 rcu_assign_pointer(dev->rx_substream, substream);
216 }
217 break;
218 case SNDRV_PCM_TRIGGER_STOP:
219 case SNDRV_PCM_TRIGGER_SUSPEND:
220 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
221 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
222 rcu_assign_pointer(dev->tx_substream, NULL);
223 else
224 rcu_assign_pointer(dev->rx_substream, NULL);
225 break;
226 default:
227 ret = -EINVAL;
228 break;
229 }
230
231 return ret;
232}
233
234static snd_pcm_uframes_t dw_pcm_pointer(struct snd_pcm_substream *substream)
235{
236 struct snd_pcm_runtime *runtime = substream->runtime;
237 struct dw_i2s_dev *dev = runtime->private_data;
238 snd_pcm_uframes_t pos;
239
240 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
241 pos = READ_ONCE(dev->tx_ptr);
242 else
243 pos = READ_ONCE(dev->rx_ptr);
244
245 return pos < runtime->buffer_size ? pos : 0;
246}
247
248static int dw_pcm_new(struct snd_soc_pcm_runtime *rtd)
249{
250 size_t size = dw_pcm_hardware.buffer_bytes_max;
251
252 snd_pcm_lib_preallocate_pages_for_all(rtd->pcm,
253 SNDRV_DMA_TYPE_CONTINUOUS,
254 snd_dma_continuous_data(GFP_KERNEL), size, size);
255 return 0;
256}
257
258static void dw_pcm_free(struct snd_pcm *pcm)
259{
260 snd_pcm_lib_preallocate_free_for_all(pcm);
261}
262
263static const struct snd_pcm_ops dw_pcm_ops = {
264 .open = dw_pcm_open,
265 .close = dw_pcm_close,
266 .ioctl = snd_pcm_lib_ioctl,
267 .hw_params = dw_pcm_hw_params,
268 .hw_free = dw_pcm_hw_free,
269 .trigger = dw_pcm_trigger,
270 .pointer = dw_pcm_pointer,
271};
272
273static const struct snd_soc_component_driver dw_pcm_component = {
274 .pcm_new = dw_pcm_new,
275 .pcm_free = dw_pcm_free,
276 .ops = &dw_pcm_ops,
277};
278
279int dw_pcm_register(struct platform_device *pdev)
280{
281 return devm_snd_soc_register_component(&pdev->dev, &dw_pcm_component,
282 NULL, 0);
283}
284
