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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * ALSA PCM device for the4 * ALSA interface to ivtv PCM capture streams5 *6 * Copyright (C) 2009,2012 Andy Walls <awalls@md.metrocast.net>7 * Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>8 *9 * Portions of this work were sponsored by ONELAN Limited for the cx18 driver10 */11 12#include "ivtv-driver.h"13#include "ivtv-queue.h"14#include "ivtv-streams.h"15#include "ivtv-fileops.h"16#include "ivtv-alsa.h"17#include "ivtv-alsa-pcm.h"18 19#include <sound/core.h>20#include <sound/pcm.h>21 22 23static unsigned int pcm_debug;24module_param(pcm_debug, int, 0644);25MODULE_PARM_DESC(pcm_debug, "enable debug messages for pcm");26 27#define dprintk(fmt, arg...) \28 do { \29 if (pcm_debug) \30 pr_info("ivtv-alsa-pcm %s: " fmt, __func__, ##arg); \31 } while (0)32 33static const struct snd_pcm_hardware snd_ivtv_hw_capture = {34 .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |35 SNDRV_PCM_INFO_MMAP |36 SNDRV_PCM_INFO_INTERLEAVED |37 SNDRV_PCM_INFO_MMAP_VALID,38 39 .formats = SNDRV_PCM_FMTBIT_S16_LE,40 41 .rates = SNDRV_PCM_RATE_48000,42 43 .rate_min = 48000,44 .rate_max = 48000,45 .channels_min = 2,46 .channels_max = 2,47 .buffer_bytes_max = 62720 * 8, /* just about the value in usbaudio.c */48 .period_bytes_min = 64, /* 12544/2, */49 .period_bytes_max = 12544,50 .periods_min = 2,51 .periods_max = 98, /* 12544, */52};53 54static void ivtv_alsa_announce_pcm_data(struct snd_ivtv_card *itvsc,55 u8 *pcm_data,56 size_t num_bytes)57{58 struct snd_pcm_substream *substream;59 struct snd_pcm_runtime *runtime;60 unsigned int oldptr;61 unsigned int stride;62 int period_elapsed = 0;63 int length;64 65 dprintk("ivtv alsa announce ptr=%p data=%p num_bytes=%zu\n", itvsc,66 pcm_data, num_bytes);67 68 substream = itvsc->capture_pcm_substream;69 if (substream == NULL) {70 dprintk("substream was NULL\n");71 return;72 }73 74 runtime = substream->runtime;75 if (runtime == NULL) {76 dprintk("runtime was NULL\n");77 return;78 }79 80 stride = runtime->frame_bits >> 3;81 if (stride == 0) {82 dprintk("stride is zero\n");83 return;84 }85 86 length = num_bytes / stride;87 if (length == 0) {88 dprintk("%s: length was zero\n", __func__);89 return;90 }91 92 if (runtime->dma_area == NULL) {93 dprintk("dma area was NULL - ignoring\n");94 return;95 }96 97 oldptr = itvsc->hwptr_done_capture;98 if (oldptr + length >= runtime->buffer_size) {99 unsigned int cnt =100 runtime->buffer_size - oldptr;101 memcpy(runtime->dma_area + oldptr * stride, pcm_data,102 cnt * stride);103 memcpy(runtime->dma_area, pcm_data + cnt * stride,104 length * stride - cnt * stride);105 } else {106 memcpy(runtime->dma_area + oldptr * stride, pcm_data,107 length * stride);108 }109 snd_pcm_stream_lock(substream);110 111 itvsc->hwptr_done_capture += length;112 if (itvsc->hwptr_done_capture >=113 runtime->buffer_size)114 itvsc->hwptr_done_capture -=115 runtime->buffer_size;116 117 itvsc->capture_transfer_done += length;118 if (itvsc->capture_transfer_done >=119 runtime->period_size) {120 itvsc->capture_transfer_done -=121 runtime->period_size;122 period_elapsed = 1;123 }124 125 snd_pcm_stream_unlock(substream);126 127 if (period_elapsed)128 snd_pcm_period_elapsed(substream);129}130 131static int snd_ivtv_pcm_capture_open(struct snd_pcm_substream *substream)132{133 struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);134 struct snd_pcm_runtime *runtime = substream->runtime;135 struct v4l2_device *v4l2_dev = itvsc->v4l2_dev;136 struct ivtv *itv = to_ivtv(v4l2_dev);137 struct ivtv_stream *s;138 struct ivtv_open_id item;139 int ret;140 141 /* Instruct the CX2341[56] to start sending packets */142 snd_ivtv_lock(itvsc);143 144 if (ivtv_init_on_first_open(itv)) {145 snd_ivtv_unlock(itvsc);146 return -ENXIO;147 }148 149 s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];150 151 v4l2_fh_init(&item.fh, &s->vdev);152 item.itv = itv;153 item.type = s->type;154 155 /* See if the stream is available */156 if (ivtv_claim_stream(&item, item.type)) {157 /* No, it's already in use */158 v4l2_fh_exit(&item.fh);159 snd_ivtv_unlock(itvsc);160 return -EBUSY;161 }162 163 if (test_bit(IVTV_F_S_STREAMOFF, &s->s_flags) ||164 test_and_set_bit(IVTV_F_S_STREAMING, &s->s_flags)) {165 /* We're already streaming. No additional action required */166 snd_ivtv_unlock(itvsc);167 return 0;168 }169 170 171 runtime->hw = snd_ivtv_hw_capture;172 snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);173 itvsc->capture_pcm_substream = substream;174 runtime->private_data = itv;175 176 itv->pcm_announce_callback = ivtv_alsa_announce_pcm_data;177 178 /* Not currently streaming, so start it up */179 set_bit(IVTV_F_S_STREAMING, &s->s_flags);180 ret = ivtv_start_v4l2_encode_stream(s);181 snd_ivtv_unlock(itvsc);182 183 return ret;184}185 186static int snd_ivtv_pcm_capture_close(struct snd_pcm_substream *substream)187{188 struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);189 struct v4l2_device *v4l2_dev = itvsc->v4l2_dev;190 struct ivtv *itv = to_ivtv(v4l2_dev);191 struct ivtv_stream *s;192 193 /* Instruct the ivtv to stop sending packets */194 snd_ivtv_lock(itvsc);195 s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];196 ivtv_stop_v4l2_encode_stream(s, 0);197 clear_bit(IVTV_F_S_STREAMING, &s->s_flags);198 199 ivtv_release_stream(s);200 201 itv->pcm_announce_callback = NULL;202 snd_ivtv_unlock(itvsc);203 204 return 0;205}206 207static int snd_ivtv_pcm_prepare(struct snd_pcm_substream *substream)208{209 struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);210 211 itvsc->hwptr_done_capture = 0;212 itvsc->capture_transfer_done = 0;213 214 return 0;215}216 217static int snd_ivtv_pcm_trigger(struct snd_pcm_substream *substream, int cmd)218{219 return 0;220}221 222static223snd_pcm_uframes_t snd_ivtv_pcm_pointer(struct snd_pcm_substream *substream)224{225 unsigned long flags;226 snd_pcm_uframes_t hwptr_done;227 struct snd_ivtv_card *itvsc = snd_pcm_substream_chip(substream);228 229 spin_lock_irqsave(&itvsc->slock, flags);230 hwptr_done = itvsc->hwptr_done_capture;231 spin_unlock_irqrestore(&itvsc->slock, flags);232 233 return hwptr_done;234}235 236static const struct snd_pcm_ops snd_ivtv_pcm_capture_ops = {237 .open = snd_ivtv_pcm_capture_open,238 .close = snd_ivtv_pcm_capture_close,239 .prepare = snd_ivtv_pcm_prepare,240 .trigger = snd_ivtv_pcm_trigger,241 .pointer = snd_ivtv_pcm_pointer,242};243 244int snd_ivtv_pcm_create(struct snd_ivtv_card *itvsc)245{246 struct snd_pcm *sp;247 struct snd_card *sc = itvsc->sc;248 struct v4l2_device *v4l2_dev = itvsc->v4l2_dev;249 struct ivtv *itv = to_ivtv(v4l2_dev);250 int ret;251 252 ret = snd_pcm_new(sc, "CX2341[56] PCM",253 0, /* PCM device 0, the only one for this card */254 0, /* 0 playback substreams */255 1, /* 1 capture substream */256 &sp);257 if (ret) {258 IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",259 __func__, ret);260 goto err_exit;261 }262 263 spin_lock_init(&itvsc->slock);264 265 snd_pcm_set_ops(sp, SNDRV_PCM_STREAM_CAPTURE,266 &snd_ivtv_pcm_capture_ops);267 snd_pcm_set_managed_buffer_all(sp, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);268 sp->info_flags = 0;269 sp->private_data = itvsc;270 strscpy(sp->name, itv->card_name, sizeof(sp->name));271 272 return 0;273 274err_exit:275 return ret;276}277