ASoC: STI: Fix null ptr deference in IRQ handler
[sfrench/cifs-2.6.git] / sound / soc / sti / uniperif_reader.c
1 /*
2  * Copyright (C) STMicroelectronics SA 2015
3  * Authors: Arnaud Pouliquen <arnaud.pouliquen@st.com>
4  *          for STMicroelectronics.
5  * License terms:  GNU General Public License (GPL), version 2
6  */
7
8 #include <sound/soc.h>
9
10 #include "uniperif.h"
11
12 #define UNIPERIF_READER_I2S_IN 0 /* reader id connected to I2S/TDM TX bus */
13 /*
14  * Note: snd_pcm_hardware is linked to DMA controller but is declared here to
15  * integrate unireader capability in term of rate and supported channels
16  */
17 static const struct snd_pcm_hardware uni_reader_pcm_hw = {
18         .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
19                 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_MMAP |
20                 SNDRV_PCM_INFO_MMAP_VALID,
21         .formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE,
22
23         .rates = SNDRV_PCM_RATE_CONTINUOUS,
24         .rate_min = 8000,
25         .rate_max = 96000,
26
27         .channels_min = 2,
28         .channels_max = 8,
29
30         .periods_min = 2,
31         .periods_max = 48,
32
33         .period_bytes_min = 128,
34         .period_bytes_max = 64 * PAGE_SIZE,
35         .buffer_bytes_max = 256 * PAGE_SIZE
36 };
37
38 /*
39  * uni_reader_irq_handler
40  * In case of error audio stream is stopped; stop action is protected via PCM
41  * stream lock  to avoid race condition with trigger callback.
42  */
43 static irqreturn_t uni_reader_irq_handler(int irq, void *dev_id)
44 {
45         irqreturn_t ret = IRQ_NONE;
46         struct uniperif *reader = dev_id;
47         unsigned int status;
48
49         spin_lock(&reader->irq_lock);
50         if (!reader->substream)
51                 goto irq_spin_unlock;
52
53         snd_pcm_stream_lock(reader->substream);
54         if (reader->state == UNIPERIF_STATE_STOPPED) {
55                 /* Unexpected IRQ: do nothing */
56                 dev_warn(reader->dev, "unexpected IRQ\n");
57                 goto stream_unlock;
58         }
59
60         /* Get interrupt status & clear them immediately */
61         status = GET_UNIPERIF_ITS(reader);
62         SET_UNIPERIF_ITS_BCLR(reader, status);
63
64         /* Check for fifo overflow error */
65         if (unlikely(status & UNIPERIF_ITS_FIFO_ERROR_MASK(reader))) {
66                 dev_err(reader->dev, "FIFO error detected\n");
67
68                 snd_pcm_stop(reader->substream, SNDRV_PCM_STATE_XRUN);
69
70                 ret = IRQ_HANDLED;
71         }
72
73 stream_unlock:
74         snd_pcm_stream_unlock(reader->substream);
75 irq_spin_unlock:
76         spin_unlock(&reader->irq_lock);
77
78         return ret;
79 }
80
81 static int uni_reader_prepare_pcm(struct snd_pcm_runtime *runtime,
82                                   struct uniperif *reader)
83 {
84         int slot_width;
85
86         /* Force slot width to 32 in I2S mode */
87         if ((reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK)
88                 == SND_SOC_DAIFMT_I2S) {
89                 slot_width = 32;
90         } else {
91                 switch (runtime->format) {
92                 case SNDRV_PCM_FORMAT_S16_LE:
93                         slot_width = 16;
94                         break;
95                 default:
96                         slot_width = 32;
97                         break;
98                 }
99         }
100
101         /* Number of bits per subframe (i.e one channel sample) on input. */
102         switch (slot_width) {
103         case 32:
104                 SET_UNIPERIF_I2S_FMT_NBIT_32(reader);
105                 SET_UNIPERIF_I2S_FMT_DATA_SIZE_32(reader);
106                 break;
107         case 16:
108                 SET_UNIPERIF_I2S_FMT_NBIT_16(reader);
109                 SET_UNIPERIF_I2S_FMT_DATA_SIZE_16(reader);
110                 break;
111         default:
112                 dev_err(reader->dev, "subframe format not supported\n");
113                 return -EINVAL;
114         }
115
116         /* Configure data memory format */
117         switch (runtime->format) {
118         case SNDRV_PCM_FORMAT_S16_LE:
119                 /* One data word contains two samples */
120                 SET_UNIPERIF_CONFIG_MEM_FMT_16_16(reader);
121                 break;
122
123         case SNDRV_PCM_FORMAT_S32_LE:
124                 /*
125                  * Actually "16 bits/0 bits" means "32/28/24/20/18/16 bits
126                  * on the MSB then zeros (if less than 32 bytes)"...
127                  */
128                 SET_UNIPERIF_CONFIG_MEM_FMT_16_0(reader);
129                 break;
130
131         default:
132                 dev_err(reader->dev, "format not supported\n");
133                 return -EINVAL;
134         }
135
136         /* Number of channels must be even */
137         if ((runtime->channels % 2) || (runtime->channels < 2) ||
138             (runtime->channels > 10)) {
139                 dev_err(reader->dev, "%s: invalid nb of channels\n", __func__);
140                 return -EINVAL;
141         }
142
143         SET_UNIPERIF_I2S_FMT_NUM_CH(reader, runtime->channels / 2);
144         SET_UNIPERIF_I2S_FMT_ORDER_MSB(reader);
145
146         return 0;
147 }
148
149 static int uni_reader_prepare_tdm(struct snd_pcm_runtime *runtime,
150                                   struct uniperif *reader)
151 {
152         int frame_size; /* user tdm frame size in bytes */
153         /* default unip TDM_WORD_POS_X_Y */
154         unsigned int word_pos[4] = {
155                 0x04060002, 0x0C0E080A, 0x14161012, 0x1C1E181A};
156
157         frame_size = sti_uniperiph_get_user_frame_size(runtime);
158
159         /* fix 16/0 format */
160         SET_UNIPERIF_CONFIG_MEM_FMT_16_0(reader);
161         SET_UNIPERIF_I2S_FMT_DATA_SIZE_32(reader);
162
163         /* number of words inserted on the TDM line */
164         SET_UNIPERIF_I2S_FMT_NUM_CH(reader, frame_size / 4 / 2);
165
166         SET_UNIPERIF_I2S_FMT_ORDER_MSB(reader);
167         SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
168         SET_UNIPERIF_TDM_ENABLE_TDM_ENABLE(reader);
169
170         /*
171          * set the timeslots allocation for words in FIFO
172          *
173          * HW bug: (LSB word < MSB word) => this config is not possible
174          *         So if we want (LSB word < MSB) word, then it shall be
175          *         handled by user
176          */
177         sti_uniperiph_get_tdm_word_pos(reader, word_pos);
178         SET_UNIPERIF_TDM_WORD_POS(reader, 1_2, word_pos[WORD_1_2]);
179         SET_UNIPERIF_TDM_WORD_POS(reader, 3_4, word_pos[WORD_3_4]);
180         SET_UNIPERIF_TDM_WORD_POS(reader, 5_6, word_pos[WORD_5_6]);
181         SET_UNIPERIF_TDM_WORD_POS(reader, 7_8, word_pos[WORD_7_8]);
182
183         return 0;
184 }
185
186 static int uni_reader_prepare(struct snd_pcm_substream *substream,
187                               struct snd_soc_dai *dai)
188 {
189         struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
190         struct uniperif *reader = priv->dai_data.uni;
191         struct snd_pcm_runtime *runtime = substream->runtime;
192         int transfer_size, trigger_limit, ret;
193
194         /* The reader should be stopped */
195         if (reader->state != UNIPERIF_STATE_STOPPED) {
196                 dev_err(reader->dev, "%s: invalid reader state %d\n", __func__,
197                         reader->state);
198                 return -EINVAL;
199         }
200
201         /* Calculate transfer size (in fifo cells and bytes) for frame count */
202         if (reader->type == SND_ST_UNIPERIF_TYPE_TDM) {
203                 /* transfer size = unip frame size (in 32 bits FIFO cell) */
204                 transfer_size =
205                         sti_uniperiph_get_user_frame_size(runtime) / 4;
206         } else {
207                 transfer_size = runtime->channels * UNIPERIF_FIFO_FRAMES;
208         }
209
210         /* Calculate number of empty cells available before asserting DREQ */
211         if (reader->ver < SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0)
212                 trigger_limit = UNIPERIF_FIFO_SIZE - transfer_size;
213         else
214                 /*
215                  * Since SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0
216                  * FDMA_TRIGGER_LIMIT also controls when the state switches
217                  * from OFF or STANDBY to AUDIO DATA.
218                  */
219                 trigger_limit = transfer_size;
220
221         /* Trigger limit must be an even number */
222         if ((!trigger_limit % 2) ||
223             (trigger_limit != 1 && transfer_size % 2) ||
224             (trigger_limit > UNIPERIF_CONFIG_DMA_TRIG_LIMIT_MASK(reader))) {
225                 dev_err(reader->dev, "invalid trigger limit %d\n",
226                         trigger_limit);
227                 return -EINVAL;
228         }
229
230         SET_UNIPERIF_CONFIG_DMA_TRIG_LIMIT(reader, trigger_limit);
231
232         if (UNIPERIF_TYPE_IS_TDM(reader))
233                 ret = uni_reader_prepare_tdm(runtime, reader);
234         else
235                 ret = uni_reader_prepare_pcm(runtime, reader);
236         if (ret)
237                 return ret;
238
239         switch (reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK) {
240         case SND_SOC_DAIFMT_I2S:
241                 SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
242                 SET_UNIPERIF_I2S_FMT_PADDING_I2S_MODE(reader);
243                 break;
244         case SND_SOC_DAIFMT_LEFT_J:
245                 SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
246                 SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
247                 break;
248         case SND_SOC_DAIFMT_RIGHT_J:
249                 SET_UNIPERIF_I2S_FMT_ALIGN_RIGHT(reader);
250                 SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
251                 break;
252         default:
253                 dev_err(reader->dev, "format not supported\n");
254                 return -EINVAL;
255         }
256
257         /* Data clocking (changing) on the rising/falling edge */
258         switch (reader->daifmt & SND_SOC_DAIFMT_INV_MASK) {
259         case SND_SOC_DAIFMT_NB_NF:
260                 SET_UNIPERIF_I2S_FMT_LR_POL_LOW(reader);
261                 SET_UNIPERIF_I2S_FMT_SCLK_EDGE_RISING(reader);
262                 break;
263         case SND_SOC_DAIFMT_NB_IF:
264                 SET_UNIPERIF_I2S_FMT_LR_POL_HIG(reader);
265                 SET_UNIPERIF_I2S_FMT_SCLK_EDGE_RISING(reader);
266                 break;
267         case SND_SOC_DAIFMT_IB_NF:
268                 SET_UNIPERIF_I2S_FMT_LR_POL_LOW(reader);
269                 SET_UNIPERIF_I2S_FMT_SCLK_EDGE_FALLING(reader);
270                 break;
271         case SND_SOC_DAIFMT_IB_IF:
272                 SET_UNIPERIF_I2S_FMT_LR_POL_HIG(reader);
273                 SET_UNIPERIF_I2S_FMT_SCLK_EDGE_FALLING(reader);
274                 break;
275         }
276
277         /* Clear any pending interrupts */
278         SET_UNIPERIF_ITS_BCLR(reader, GET_UNIPERIF_ITS(reader));
279
280         SET_UNIPERIF_I2S_FMT_NO_OF_SAMPLES_TO_READ(reader, 0);
281
282         /* Set the interrupt mask */
283         SET_UNIPERIF_ITM_BSET_DMA_ERROR(reader);
284         SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
285         SET_UNIPERIF_ITM_BSET_MEM_BLK_READ(reader);
286
287         /* Enable underflow recovery interrupts */
288         if (reader->underflow_enabled) {
289                 SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_DONE(reader);
290                 SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_FAILED(reader);
291         }
292
293         /* Reset uniperipheral reader */
294         return sti_uniperiph_reset(reader);
295 }
296
297 static int uni_reader_start(struct uniperif *reader)
298 {
299         /* The reader should be stopped */
300         if (reader->state != UNIPERIF_STATE_STOPPED) {
301                 dev_err(reader->dev, "%s: invalid reader state\n", __func__);
302                 return -EINVAL;
303         }
304
305         /* Enable reader interrupts (and clear possible stalled ones) */
306         SET_UNIPERIF_ITS_BCLR_FIFO_ERROR(reader);
307         SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
308
309         /* Launch the reader */
310         SET_UNIPERIF_CTRL_OPERATION_PCM_DATA(reader);
311
312         /* Update state to started */
313         reader->state = UNIPERIF_STATE_STARTED;
314         return 0;
315 }
316
317 static int uni_reader_stop(struct uniperif *reader)
318 {
319         /* The reader should not be in stopped state */
320         if (reader->state == UNIPERIF_STATE_STOPPED) {
321                 dev_err(reader->dev, "%s: invalid reader state\n", __func__);
322                 return -EINVAL;
323         }
324
325         /* Turn the reader off */
326         SET_UNIPERIF_CTRL_OPERATION_OFF(reader);
327
328         /* Disable interrupts */
329         SET_UNIPERIF_ITM_BCLR(reader, GET_UNIPERIF_ITM(reader));
330
331         /* Update state to stopped and return */
332         reader->state = UNIPERIF_STATE_STOPPED;
333
334         return 0;
335 }
336
337 static int  uni_reader_trigger(struct snd_pcm_substream *substream,
338                                int cmd, struct snd_soc_dai *dai)
339 {
340         struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
341         struct uniperif *reader = priv->dai_data.uni;
342
343         switch (cmd) {
344         case SNDRV_PCM_TRIGGER_START:
345                 return  uni_reader_start(reader);
346         case SNDRV_PCM_TRIGGER_STOP:
347                 return  uni_reader_stop(reader);
348         default:
349                 return -EINVAL;
350         }
351 }
352
353 static int uni_reader_startup(struct snd_pcm_substream *substream,
354                               struct snd_soc_dai *dai)
355 {
356         struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
357         struct uniperif *reader = priv->dai_data.uni;
358         unsigned long flags;
359         int ret;
360
361         spin_lock_irqsave(&reader->irq_lock, flags);
362         reader->substream = substream;
363         spin_unlock_irqrestore(&reader->irq_lock, flags);
364
365         if (!UNIPERIF_TYPE_IS_TDM(reader))
366                 return 0;
367
368         /* refine hw constraint in tdm mode */
369         ret = snd_pcm_hw_rule_add(substream->runtime, 0,
370                                   SNDRV_PCM_HW_PARAM_CHANNELS,
371                                   sti_uniperiph_fix_tdm_chan,
372                                   reader, SNDRV_PCM_HW_PARAM_CHANNELS,
373                                   -1);
374         if (ret < 0)
375                 return ret;
376
377         return snd_pcm_hw_rule_add(substream->runtime, 0,
378                                    SNDRV_PCM_HW_PARAM_FORMAT,
379                                    sti_uniperiph_fix_tdm_format,
380                                    reader, SNDRV_PCM_HW_PARAM_FORMAT,
381                                    -1);
382 }
383
384 static void uni_reader_shutdown(struct snd_pcm_substream *substream,
385                                 struct snd_soc_dai *dai)
386 {
387         struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
388         struct uniperif *reader = priv->dai_data.uni;
389         unsigned long flags;
390
391         spin_lock_irqsave(&reader->irq_lock, flags);
392         if (reader->state != UNIPERIF_STATE_STOPPED) {
393                 /* Stop the reader */
394                 uni_reader_stop(reader);
395         }
396         reader->substream = NULL;
397         spin_unlock_irqrestore(&reader->irq_lock, flags);
398 }
399
400 static const struct snd_soc_dai_ops uni_reader_dai_ops = {
401                 .startup = uni_reader_startup,
402                 .shutdown = uni_reader_shutdown,
403                 .prepare = uni_reader_prepare,
404                 .trigger = uni_reader_trigger,
405                 .hw_params = sti_uniperiph_dai_hw_params,
406                 .set_fmt = sti_uniperiph_dai_set_fmt,
407                 .set_tdm_slot = sti_uniperiph_set_tdm_slot
408 };
409
410 int uni_reader_init(struct platform_device *pdev,
411                     struct uniperif *reader)
412 {
413         int ret = 0;
414
415         reader->dev = &pdev->dev;
416         reader->state = UNIPERIF_STATE_STOPPED;
417         reader->dai_ops = &uni_reader_dai_ops;
418
419         if (UNIPERIF_TYPE_IS_TDM(reader))
420                 reader->hw = &uni_tdm_hw;
421         else
422                 reader->hw = &uni_reader_pcm_hw;
423
424         ret = devm_request_irq(&pdev->dev, reader->irq,
425                                uni_reader_irq_handler, IRQF_SHARED,
426                                dev_name(&pdev->dev), reader);
427         if (ret < 0) {
428                 dev_err(&pdev->dev, "Failed to request IRQ\n");
429                 return -EBUSY;
430         }
431
432         spin_lock_init(&reader->irq_lock);
433
434         return 0;
435 }
436 EXPORT_SYMBOL_GPL(uni_reader_init);