Alex Elder | 2de1a8b | 2015-05-22 12:59:15 -0500 | [diff] [blame^] | 1 | /* |
| 2 | * Greybus audio Pulse Code Modulation (PCM) driver |
| 3 | * |
| 4 | * Copyright 2015 Google Inc. |
| 5 | * Copyright 2015 Linaro Ltd. |
| 6 | * |
| 7 | * Released under the GPLv2 only. |
| 8 | */ |
| 9 | |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 10 | #include <linux/kernel.h> |
| 11 | #include <linux/device.h> |
| 12 | #include <linux/interrupt.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/platform_device.h> |
| 15 | #include <linux/workqueue.h> |
| 16 | #include <linux/i2c.h> |
| 17 | #include <sound/core.h> |
| 18 | #include <sound/pcm.h> |
| 19 | #include <sound/pcm_params.h> |
| 20 | #include <sound/soc.h> |
| 21 | #include <sound/dmaengine_pcm.h> |
| 22 | #include <sound/simple_card.h> |
Alex Elder | e9385e5 | 2015-05-22 12:35:31 -0500 | [diff] [blame] | 23 | |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 24 | #include "greybus.h" |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 25 | #include "audio.h" |
| 26 | |
| 27 | /* |
| 28 | * timer/workqueue logic for pushing pcm data. |
| 29 | * |
| 30 | * Since when we are playing audio, we don't get any |
| 31 | * status or feedback from the codec, we have to use a |
| 32 | * hrtimer to trigger sending data to the remote codec. |
| 33 | * However since the hrtimer runs in irq context, so we |
| 34 | * have to schedule a workqueue to actually send the |
| 35 | * greybus data. |
| 36 | */ |
| 37 | |
| 38 | static void gb_pcm_work(struct work_struct *work) |
| 39 | { |
| 40 | struct gb_snd *snd_dev = container_of(work, struct gb_snd, work); |
| 41 | struct snd_pcm_substream *substream = snd_dev->substream; |
| 42 | struct snd_pcm_runtime *runtime = substream->runtime; |
| 43 | unsigned int stride, frames, oldptr; |
Mark A. Greer | f9a4fee | 2015-05-21 15:57:01 -0700 | [diff] [blame] | 44 | int period_elapsed, ret; |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 45 | char *address; |
| 46 | long len; |
| 47 | |
| 48 | if (!snd_dev) |
| 49 | return; |
| 50 | |
Mark A. Greer | f9a4fee | 2015-05-21 15:57:01 -0700 | [diff] [blame] | 51 | if (!atomic_read(&snd_dev->running)) { |
| 52 | if (snd_dev->cport_active) { |
| 53 | ret = gb_i2s_mgmt_deactivate_cport( |
Mark A. Greer | 48229e5 | 2015-05-21 15:57:02 -0700 | [diff] [blame] | 54 | snd_dev->mgmt_connection, |
| 55 | snd_dev->i2s_tx_connection->bundle_cport_id); |
Mark A. Greer | f9a4fee | 2015-05-21 15:57:01 -0700 | [diff] [blame] | 56 | if (ret) /* XXX Do what else with failure? */ |
| 57 | pr_err("deactivate_cport failed: %d\n", ret); |
| 58 | |
| 59 | snd_dev->cport_active = false; |
| 60 | } |
| 61 | |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 62 | return; |
Mark A. Greer | f9a4fee | 2015-05-21 15:57:01 -0700 | [diff] [blame] | 63 | } else if (!snd_dev->cport_active) { |
| 64 | ret = gb_i2s_mgmt_activate_cport(snd_dev->mgmt_connection, |
Mark A. Greer | 48229e5 | 2015-05-21 15:57:02 -0700 | [diff] [blame] | 65 | snd_dev->i2s_tx_connection->bundle_cport_id); |
Mark A. Greer | f9a4fee | 2015-05-21 15:57:01 -0700 | [diff] [blame] | 66 | if (ret) |
| 67 | pr_err("activate_cport failed: %d\n", ret); |
| 68 | |
| 69 | snd_dev->cport_active = true; |
| 70 | } |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 71 | |
| 72 | address = runtime->dma_area + snd_dev->hwptr_done; |
| 73 | |
| 74 | len = frames_to_bytes(runtime, |
| 75 | runtime->buffer_size) - snd_dev->hwptr_done; |
| 76 | len = min(len, MAX_SEND_DATA_LEN); |
| 77 | gb_i2s_send_data(snd_dev->i2s_tx_connection, snd_dev->send_data_req_buf, |
| 78 | address, len, snd_dev->send_data_sample_count); |
| 79 | |
| 80 | snd_dev->send_data_sample_count += CONFIG_SAMPLES_PER_MSG; |
| 81 | |
| 82 | stride = runtime->frame_bits >> 3; |
| 83 | frames = len/stride; |
| 84 | |
| 85 | snd_pcm_stream_lock(substream); |
| 86 | oldptr = snd_dev->hwptr_done; |
| 87 | snd_dev->hwptr_done += len; |
| 88 | if (snd_dev->hwptr_done >= runtime->buffer_size * stride) |
| 89 | snd_dev->hwptr_done -= runtime->buffer_size * stride; |
| 90 | |
| 91 | frames = (len + (oldptr % stride)) / stride; |
| 92 | |
| 93 | snd_dev->transfer_done += frames; |
| 94 | if (snd_dev->transfer_done >= runtime->period_size) { |
| 95 | snd_dev->transfer_done -= runtime->period_size; |
| 96 | period_elapsed = 1; |
| 97 | } |
| 98 | |
| 99 | snd_pcm_stream_unlock(substream); |
| 100 | if (period_elapsed) |
| 101 | snd_pcm_period_elapsed(snd_dev->substream); |
| 102 | } |
| 103 | |
| 104 | static enum hrtimer_restart gb_pcm_timer_function(struct hrtimer *hrtimer) |
| 105 | { |
| 106 | struct gb_snd *snd_dev = container_of(hrtimer, struct gb_snd, timer); |
| 107 | |
| 108 | if (!atomic_read(&snd_dev->running)) |
| 109 | return HRTIMER_NORESTART; |
| 110 | queue_work(snd_dev->workqueue, &snd_dev->work); |
| 111 | hrtimer_forward_now(hrtimer, ns_to_ktime(CONFIG_PERIOD_NS)); |
| 112 | return HRTIMER_RESTART; |
| 113 | } |
| 114 | |
| 115 | void gb_pcm_hrtimer_start(struct gb_snd *snd_dev) |
| 116 | { |
| 117 | atomic_set(&snd_dev->running, 1); |
Mark A. Greer | f9a4fee | 2015-05-21 15:57:01 -0700 | [diff] [blame] | 118 | queue_work(snd_dev->workqueue, &snd_dev->work); /* Activates CPort */ |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 119 | hrtimer_start(&snd_dev->timer, ns_to_ktime(CONFIG_PERIOD_NS), |
| 120 | HRTIMER_MODE_REL); |
| 121 | } |
| 122 | |
| 123 | void gb_pcm_hrtimer_stop(struct gb_snd *snd_dev) |
| 124 | { |
| 125 | atomic_set(&snd_dev->running, 0); |
| 126 | hrtimer_cancel(&snd_dev->timer); |
Mark A. Greer | f9a4fee | 2015-05-21 15:57:01 -0700 | [diff] [blame] | 127 | queue_work(snd_dev->workqueue, &snd_dev->work); /* Deactivates CPort */ |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 128 | } |
| 129 | |
| 130 | static int gb_pcm_hrtimer_init(struct gb_snd *snd_dev) |
| 131 | { |
| 132 | hrtimer_init(&snd_dev->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); |
| 133 | snd_dev->timer.function = gb_pcm_timer_function; |
| 134 | atomic_set(&snd_dev->running, 0); |
| 135 | snd_dev->workqueue = alloc_workqueue("gb-audio", WQ_HIGHPRI, 0); |
| 136 | if (!snd_dev->workqueue) |
| 137 | return -ENOMEM; |
| 138 | INIT_WORK(&snd_dev->work, gb_pcm_work); |
| 139 | return 0; |
| 140 | } |
| 141 | |
| 142 | |
| 143 | /* |
| 144 | * Core gb pcm structure |
| 145 | */ |
| 146 | static struct snd_pcm_hardware gb_plat_pcm_hardware = { |
| 147 | .info = SNDRV_PCM_INFO_INTERLEAVED | |
| 148 | SNDRV_PCM_INFO_MMAP | |
| 149 | SNDRV_PCM_INFO_MMAP_VALID, |
| 150 | .formats = GB_FMTS, |
| 151 | .rates = GB_RATES, |
| 152 | .rate_min = 8000, |
| 153 | .rate_max = GB_SAMPLE_RATE, |
| 154 | .channels_min = 1, |
| 155 | .channels_max = 2, |
| 156 | /* XXX - All the values below are junk */ |
| 157 | .buffer_bytes_max = 64 * 1024, |
| 158 | .period_bytes_min = 32, |
| 159 | .period_bytes_max = 8192, |
| 160 | .periods_min = 2, |
| 161 | .periods_max = 32, |
| 162 | }; |
| 163 | |
| 164 | static snd_pcm_uframes_t gb_pcm_pointer(struct snd_pcm_substream *substream) |
| 165 | { |
| 166 | struct snd_soc_pcm_runtime *rtd = substream->private_data; |
| 167 | struct gb_snd *snd_dev; |
| 168 | |
| 169 | snd_dev = snd_soc_dai_get_drvdata(rtd->cpu_dai); |
| 170 | |
| 171 | return snd_dev->hwptr_done / (substream->runtime->frame_bits >> 3); |
| 172 | } |
| 173 | |
| 174 | static int gb_pcm_prepare(struct snd_pcm_substream *substream) |
| 175 | { |
| 176 | struct snd_soc_pcm_runtime *rtd = substream->private_data; |
| 177 | struct gb_snd *snd_dev; |
| 178 | |
| 179 | snd_dev = snd_soc_dai_get_drvdata(rtd->cpu_dai); |
| 180 | snd_dev->hwptr_done = 0; |
| 181 | snd_dev->transfer_done = 0; |
| 182 | return 0; |
| 183 | } |
| 184 | |
| 185 | static unsigned int rates[] = {GB_SAMPLE_RATE}; |
| 186 | static struct snd_pcm_hw_constraint_list constraints_rates = { |
| 187 | .count = ARRAY_SIZE(rates), |
| 188 | .list = rates, |
| 189 | .mask = 0, |
| 190 | }; |
| 191 | |
| 192 | static int gb_pcm_open(struct snd_pcm_substream *substream) |
| 193 | { |
| 194 | struct snd_pcm_runtime *runtime = substream->runtime; |
| 195 | struct snd_soc_pcm_runtime *rtd = substream->private_data; |
| 196 | struct gb_snd *snd_dev; |
| 197 | unsigned long flags; |
| 198 | int ret; |
| 199 | |
| 200 | snd_dev = snd_soc_dai_get_drvdata(rtd->cpu_dai); |
| 201 | |
| 202 | spin_lock_irqsave(&snd_dev->lock, flags); |
| 203 | runtime->private_data = snd_dev; |
| 204 | snd_dev->substream = substream; |
| 205 | ret = gb_pcm_hrtimer_init(snd_dev); |
| 206 | spin_unlock_irqrestore(&snd_dev->lock, flags); |
| 207 | |
| 208 | if (ret) |
| 209 | return ret; |
| 210 | |
| 211 | snd_soc_set_runtime_hwparams(substream, &gb_plat_pcm_hardware); |
| 212 | |
| 213 | ret = snd_pcm_hw_constraint_list(substream->runtime, 0, |
| 214 | SNDRV_PCM_HW_PARAM_RATE, |
| 215 | &constraints_rates); |
| 216 | if (ret < 0) |
| 217 | return ret; |
| 218 | |
| 219 | return snd_pcm_hw_constraint_integer(runtime, |
| 220 | SNDRV_PCM_HW_PARAM_PERIODS); |
| 221 | } |
| 222 | |
| 223 | static int gb_pcm_close(struct snd_pcm_substream *substream) |
| 224 | { |
| 225 | substream->runtime->private_data = NULL; |
| 226 | return 0; |
| 227 | } |
| 228 | |
| 229 | static int gb_pcm_hw_params(struct snd_pcm_substream *substream, |
| 230 | struct snd_pcm_hw_params *hw_params) |
| 231 | { |
Mark A. Greer | 6b34099 | 2015-05-21 15:57:03 -0700 | [diff] [blame] | 232 | struct snd_soc_pcm_runtime *rtd = substream->private_data; |
| 233 | struct gb_snd *snd_dev; |
| 234 | int rate, chans, bytes_per_chan, is_le, ret; |
| 235 | |
| 236 | snd_dev = snd_soc_dai_get_drvdata(rtd->cpu_dai); |
| 237 | |
| 238 | rate = params_rate(hw_params); |
| 239 | chans = params_channels(hw_params); |
| 240 | bytes_per_chan = snd_pcm_format_width(params_format(hw_params)) / 8; |
| 241 | is_le = snd_pcm_format_little_endian(params_format(hw_params)); |
| 242 | |
| 243 | ret = gb_i2s_mgmt_set_cfg(snd_dev, rate, chans, bytes_per_chan, is_le); |
| 244 | if (ret) |
| 245 | return ret; |
| 246 | |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 247 | return snd_pcm_lib_malloc_pages(substream, |
| 248 | params_buffer_bytes(hw_params)); |
| 249 | } |
| 250 | |
| 251 | static int gb_pcm_hw_free(struct snd_pcm_substream *substream) |
| 252 | { |
| 253 | return snd_pcm_lib_free_pages(substream); |
| 254 | } |
| 255 | |
| 256 | static struct snd_pcm_ops gb_pcm_ops = { |
| 257 | .open = gb_pcm_open, |
| 258 | .close = gb_pcm_close, |
| 259 | .ioctl = snd_pcm_lib_ioctl, |
| 260 | .hw_params = gb_pcm_hw_params, |
| 261 | .hw_free = gb_pcm_hw_free, |
| 262 | .prepare = gb_pcm_prepare, |
| 263 | .pointer = gb_pcm_pointer, |
| 264 | }; |
| 265 | |
| 266 | static void gb_pcm_free(struct snd_pcm *pcm) |
| 267 | { |
| 268 | snd_pcm_lib_preallocate_free_for_all(pcm); |
| 269 | } |
| 270 | |
| 271 | static int gb_pcm_new(struct snd_soc_pcm_runtime *rtd) |
| 272 | { |
| 273 | struct snd_pcm *pcm = rtd->pcm; |
| 274 | |
| 275 | return snd_pcm_lib_preallocate_pages_for_all( |
| 276 | pcm, |
| 277 | SNDRV_DMA_TYPE_CONTINUOUS, |
| 278 | snd_dma_continuous_data(GFP_KERNEL), |
| 279 | PREALLOC_BUFFER, PREALLOC_BUFFER_MAX); |
| 280 | } |
| 281 | |
Greg Kroah-Hartman | 1395690 | 2015-05-11 14:09:09 -0700 | [diff] [blame] | 282 | static struct snd_soc_platform_driver gb_soc_platform = { |
John Stultz | a4749bb | 2015-05-08 12:57:36 -0700 | [diff] [blame] | 283 | .ops = &gb_pcm_ops, |
| 284 | .pcm_new = gb_pcm_new, |
| 285 | .pcm_free = gb_pcm_free, |
| 286 | }; |
| 287 | |
| 288 | static int gb_soc_platform_probe(struct platform_device *pdev) |
| 289 | { |
| 290 | return snd_soc_register_platform(&pdev->dev, &gb_soc_platform); |
| 291 | } |
| 292 | |
| 293 | static int gb_soc_platform_remove(struct platform_device *pdev) |
| 294 | { |
| 295 | snd_soc_unregister_platform(&pdev->dev); |
| 296 | return 0; |
| 297 | } |
| 298 | |
| 299 | struct platform_driver gb_audio_pcm_driver = { |
| 300 | .driver = { |
| 301 | .name = "gb-pcm-audio", |
| 302 | .owner = THIS_MODULE, |
| 303 | }, |
| 304 | .probe = gb_soc_platform_probe, |
| 305 | .remove = gb_soc_platform_remove, |
| 306 | }; |