Lars-Peter Clausen | e7f73a1 | 2012-02-22 10:49:08 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012, Analog Devices Inc. |
| 3 | * Author: Lars-Peter Clausen <lars@metafoo.de> |
| 4 | * |
| 5 | * Based on: |
| 6 | * imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de> |
| 7 | * mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc. |
| 8 | * ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org> |
| 9 | * Copyright (C) 2006 Applied Data Systems |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or modify it |
| 12 | * under the terms of the GNU General Public License as published by the |
| 13 | * Free Software Foundation; either version 2 of the License, or (at your |
| 14 | * option) any later version. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License along |
| 17 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 18 | * 675 Mass Ave, Cambridge, MA 02139, USA. |
| 19 | * |
| 20 | */ |
| 21 | #include <linux/module.h> |
| 22 | #include <linux/init.h> |
| 23 | #include <linux/dmaengine.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <sound/pcm.h> |
| 26 | #include <sound/pcm_params.h> |
| 27 | #include <sound/soc.h> |
| 28 | |
| 29 | #include <sound/dmaengine_pcm.h> |
| 30 | |
| 31 | struct dmaengine_pcm_runtime_data { |
| 32 | struct dma_chan *dma_chan; |
| 33 | |
| 34 | unsigned int pos; |
| 35 | |
| 36 | void *data; |
| 37 | }; |
| 38 | |
| 39 | static inline struct dmaengine_pcm_runtime_data *substream_to_prtd( |
| 40 | const struct snd_pcm_substream *substream) |
| 41 | { |
| 42 | return substream->runtime->private_data; |
| 43 | } |
| 44 | |
| 45 | /** |
| 46 | * snd_dmaengine_pcm_set_data - Set dmaengine substream private data |
| 47 | * @substream: PCM substream |
| 48 | * @data: Data to set |
| 49 | */ |
| 50 | void snd_dmaengine_pcm_set_data(struct snd_pcm_substream *substream, void *data) |
| 51 | { |
| 52 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 53 | |
| 54 | prtd->data = data; |
| 55 | } |
| 56 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_data); |
| 57 | |
| 58 | /** |
| 59 | * snd_dmaengine_pcm_get_data - Get dmaeinge substream private data |
| 60 | * @substream: PCM substream |
| 61 | * |
| 62 | * Returns the data previously set with snd_dmaengine_pcm_set_data |
| 63 | */ |
| 64 | void *snd_dmaengine_pcm_get_data(struct snd_pcm_substream *substream) |
| 65 | { |
| 66 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 67 | |
| 68 | return prtd->data; |
| 69 | } |
| 70 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_data); |
| 71 | |
| 72 | struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream) |
| 73 | { |
| 74 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 75 | |
| 76 | return prtd->dma_chan; |
| 77 | } |
| 78 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan); |
| 79 | |
| 80 | /** |
| 81 | * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config |
| 82 | * @substream: PCM substream |
| 83 | * @params: hw_params |
| 84 | * @slave_config: DMA slave config |
| 85 | * |
| 86 | * This function can be used to initialize a dma_slave_config from a substream |
| 87 | * and hw_params in a dmaengine based PCM driver implementation. |
| 88 | */ |
| 89 | int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream, |
| 90 | const struct snd_pcm_hw_params *params, |
| 91 | struct dma_slave_config *slave_config) |
| 92 | { |
| 93 | enum dma_slave_buswidth buswidth; |
| 94 | |
| 95 | switch (params_format(params)) { |
| 96 | case SNDRV_PCM_FORMAT_S8: |
| 97 | buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE; |
| 98 | break; |
| 99 | case SNDRV_PCM_FORMAT_S16_LE: |
| 100 | buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES; |
| 101 | break; |
| 102 | case SNDRV_PCM_FORMAT_S18_3LE: |
| 103 | case SNDRV_PCM_FORMAT_S20_3LE: |
| 104 | case SNDRV_PCM_FORMAT_S24_LE: |
| 105 | case SNDRV_PCM_FORMAT_S32_LE: |
| 106 | buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES; |
| 107 | break; |
| 108 | default: |
| 109 | return -EINVAL; |
| 110 | } |
| 111 | |
| 112 | if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { |
| 113 | slave_config->direction = DMA_MEM_TO_DEV; |
| 114 | slave_config->dst_addr_width = buswidth; |
| 115 | } else { |
| 116 | slave_config->direction = DMA_DEV_TO_MEM; |
| 117 | slave_config->src_addr_width = buswidth; |
| 118 | } |
| 119 | |
| 120 | return 0; |
| 121 | } |
| 122 | EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config); |
| 123 | |
| 124 | static void dmaengine_pcm_dma_complete(void *arg) |
| 125 | { |
| 126 | struct snd_pcm_substream *substream = arg; |
| 127 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 128 | |
| 129 | prtd->pos += snd_pcm_lib_period_bytes(substream); |
| 130 | if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream)) |
| 131 | prtd->pos = 0; |
| 132 | |
| 133 | snd_pcm_period_elapsed(substream); |
| 134 | } |
| 135 | |
| 136 | static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream) |
| 137 | { |
| 138 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 139 | struct dma_chan *chan = prtd->dma_chan; |
| 140 | struct dma_async_tx_descriptor *desc; |
| 141 | enum dma_transfer_direction direction; |
| 142 | |
| 143 | direction = snd_pcm_substream_to_dma_direction(substream); |
| 144 | |
Mika Westerberg | 7a08cf7 | 2012-03-05 14:02:14 +0100 | [diff] [blame] | 145 | prtd->pos = 0; |
Vinod Koul | 41ba6b7 | 2012-03-26 17:28:08 +0530 | [diff] [blame] | 146 | desc = dmaengine_prep_dma_cyclic(chan, |
Lars-Peter Clausen | e7f73a1 | 2012-02-22 10:49:08 +0100 | [diff] [blame] | 147 | substream->runtime->dma_addr, |
| 148 | snd_pcm_lib_buffer_bytes(substream), |
Vinod Koul | 41ba6b7 | 2012-03-26 17:28:08 +0530 | [diff] [blame] | 149 | snd_pcm_lib_period_bytes(substream), direction); |
Lars-Peter Clausen | e7f73a1 | 2012-02-22 10:49:08 +0100 | [diff] [blame] | 150 | |
| 151 | if (!desc) |
| 152 | return -ENOMEM; |
| 153 | |
| 154 | desc->callback = dmaengine_pcm_dma_complete; |
| 155 | desc->callback_param = substream; |
| 156 | dmaengine_submit(desc); |
| 157 | |
| 158 | return 0; |
| 159 | } |
| 160 | |
| 161 | /** |
| 162 | * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation |
| 163 | * @substream: PCM substream |
| 164 | * @cmd: Trigger command |
| 165 | * |
| 166 | * Returns 0 on success, a negative error code otherwise. |
| 167 | * |
| 168 | * This function can be used as the PCM trigger callback for dmaengine based PCM |
| 169 | * driver implementations. |
| 170 | */ |
| 171 | int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd) |
| 172 | { |
| 173 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 174 | int ret; |
| 175 | |
| 176 | switch (cmd) { |
| 177 | case SNDRV_PCM_TRIGGER_START: |
| 178 | ret = dmaengine_pcm_prepare_and_submit(substream); |
| 179 | if (ret) |
| 180 | return ret; |
| 181 | dma_async_issue_pending(prtd->dma_chan); |
| 182 | break; |
| 183 | case SNDRV_PCM_TRIGGER_RESUME: |
| 184 | case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: |
| 185 | dmaengine_resume(prtd->dma_chan); |
| 186 | break; |
| 187 | case SNDRV_PCM_TRIGGER_SUSPEND: |
| 188 | case SNDRV_PCM_TRIGGER_PAUSE_PUSH: |
| 189 | dmaengine_pause(prtd->dma_chan); |
| 190 | break; |
| 191 | case SNDRV_PCM_TRIGGER_STOP: |
| 192 | dmaengine_terminate_all(prtd->dma_chan); |
| 193 | break; |
| 194 | default: |
| 195 | return -EINVAL; |
| 196 | } |
| 197 | |
| 198 | return 0; |
| 199 | } |
| 200 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger); |
| 201 | |
| 202 | /** |
| 203 | * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation |
| 204 | * @substream: PCM substream |
| 205 | * |
| 206 | * This function can be used as the PCM pointer callback for dmaengine based PCM |
| 207 | * driver implementations. |
| 208 | */ |
| 209 | snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream) |
| 210 | { |
| 211 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 212 | return bytes_to_frames(substream->runtime, prtd->pos); |
| 213 | } |
| 214 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer); |
| 215 | |
| 216 | static int dmaengine_pcm_request_channel(struct dmaengine_pcm_runtime_data *prtd, |
| 217 | dma_filter_fn filter_fn, void *filter_data) |
| 218 | { |
| 219 | dma_cap_mask_t mask; |
| 220 | |
| 221 | dma_cap_zero(mask); |
| 222 | dma_cap_set(DMA_SLAVE, mask); |
| 223 | dma_cap_set(DMA_CYCLIC, mask); |
| 224 | prtd->dma_chan = dma_request_channel(mask, filter_fn, filter_data); |
| 225 | |
| 226 | if (!prtd->dma_chan) |
| 227 | return -ENXIO; |
| 228 | |
| 229 | return 0; |
| 230 | } |
| 231 | |
| 232 | /** |
| 233 | * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream |
| 234 | * @substream: PCM substream |
| 235 | * @filter_fn: Filter function used to request the DMA channel |
| 236 | * @filter_data: Data passed to the DMA filter function |
| 237 | * |
| 238 | * Returns 0 on success, a negative error code otherwise. |
| 239 | * |
| 240 | * This function will request a DMA channel using the passed filter function and |
| 241 | * data. The function should usually be called from the pcm open callback. |
| 242 | * |
| 243 | * Note that this function will use private_data field of the substream's |
| 244 | * runtime. So it is not availabe to your pcm driver implementation. If you need |
| 245 | * to keep additional data attached to a substream use |
| 246 | * snd_dmaeinge_pcm_{set,get}_data. |
| 247 | */ |
| 248 | int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream, |
| 249 | dma_filter_fn filter_fn, void *filter_data) |
| 250 | { |
| 251 | struct dmaengine_pcm_runtime_data *prtd; |
| 252 | int ret; |
| 253 | |
| 254 | ret = snd_pcm_hw_constraint_integer(substream->runtime, |
| 255 | SNDRV_PCM_HW_PARAM_PERIODS); |
| 256 | if (ret < 0) |
| 257 | return ret; |
| 258 | |
| 259 | prtd = kzalloc(sizeof(*prtd), GFP_KERNEL); |
| 260 | if (!prtd) |
| 261 | return -ENOMEM; |
| 262 | |
| 263 | ret = dmaengine_pcm_request_channel(prtd, filter_fn, filter_data); |
| 264 | if (ret < 0) { |
| 265 | kfree(prtd); |
| 266 | return ret; |
| 267 | } |
| 268 | |
| 269 | substream->runtime->private_data = prtd; |
| 270 | |
| 271 | return 0; |
| 272 | } |
| 273 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open); |
| 274 | |
| 275 | /** |
| 276 | * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream |
| 277 | * @substream: PCM substream |
| 278 | */ |
| 279 | int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream) |
| 280 | { |
| 281 | struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); |
| 282 | |
| 283 | dma_release_channel(prtd->dma_chan); |
| 284 | kfree(prtd); |
| 285 | |
| 286 | return 0; |
| 287 | } |
| 288 | EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close); |