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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Au12x0/Au1550 PSC ALSA ASoC audio support.4 *5 * (c) 2007-2008 MSC Vertriebsges.m.b.H.,6 * Manuel Lauss <manuel.lauss@gmail.com>7 *8 * DMA glue for Au1x-PSC audio.9 */10 11 12#include <linux/module.h>13#include <linux/init.h>14#include <linux/platform_device.h>15#include <linux/slab.h>16#include <linux/dma-mapping.h>17 18#include <sound/core.h>19#include <sound/pcm.h>20#include <sound/pcm_params.h>21#include <sound/soc.h>22 23#include <asm/mach-au1x00/au1000.h>24#include <asm/mach-au1x00/au1xxx_dbdma.h>25#include <asm/mach-au1x00/au1xxx_psc.h>26 27#include "psc.h"28 29/*#define PCM_DEBUG*/30 31#define DRV_NAME "dbdma2"32 33#define MSG(x...) printk(KERN_INFO "au1xpsc_pcm: " x)34#ifdef PCM_DEBUG35#define DBG MSG36#else37#define DBG(x...) do {} while (0)38#endif39 40struct au1xpsc_audio_dmadata {41 /* DDMA control data */42 unsigned int ddma_id; /* DDMA direction ID for this PSC */43 u32 ddma_chan; /* DDMA context */44 45 /* PCM context (for irq handlers) */46 struct snd_pcm_substream *substream;47 unsigned long curr_period; /* current segment DDMA is working on */48 unsigned long q_period; /* queue period(s) */49 dma_addr_t dma_area; /* address of queued DMA area */50 dma_addr_t dma_area_s; /* start address of DMA area */51 unsigned long pos; /* current byte position being played */52 unsigned long periods; /* number of SG segments in total */53 unsigned long period_bytes; /* size in bytes of one SG segment */54 55 /* runtime data */56 int msbits;57};58 59/*60 * These settings are somewhat okay, at least on my machine audio plays61 * almost skip-free. Especially the 64kB buffer seems to help a LOT.62 */63#define AU1XPSC_PERIOD_MIN_BYTES 102464#define AU1XPSC_BUFFER_MIN_BYTES 6553665 66/* PCM hardware DMA capabilities - platform specific */67static const struct snd_pcm_hardware au1xpsc_pcm_hardware = {68 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |69 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,70 .period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES,71 .period_bytes_max = 4096 * 1024 - 1,72 .periods_min = 2,73 .periods_max = 4096, /* 2 to as-much-as-you-like */74 .buffer_bytes_max = 4096 * 1024 - 1,75 .fifo_size = 16, /* fifo entries of AC97/I2S PSC */76};77 78static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd)79{80 au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area,81 cd->period_bytes, DDMA_FLAGS_IE);82 83 /* update next-to-queue period */84 ++cd->q_period;85 cd->dma_area += cd->period_bytes;86 if (cd->q_period >= cd->periods) {87 cd->q_period = 0;88 cd->dma_area = cd->dma_area_s;89 }90}91 92static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd)93{94 au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area,95 cd->period_bytes, DDMA_FLAGS_IE);96 97 /* update next-to-queue period */98 ++cd->q_period;99 cd->dma_area += cd->period_bytes;100 if (cd->q_period >= cd->periods) {101 cd->q_period = 0;102 cd->dma_area = cd->dma_area_s;103 }104}105 106static void au1x_pcm_dmatx_cb(int irq, void *dev_id)107{108 struct au1xpsc_audio_dmadata *cd = dev_id;109 110 cd->pos += cd->period_bytes;111 if (++cd->curr_period >= cd->periods) {112 cd->pos = 0;113 cd->curr_period = 0;114 }115 snd_pcm_period_elapsed(cd->substream);116 au1x_pcm_queue_tx(cd);117}118 119static void au1x_pcm_dmarx_cb(int irq, void *dev_id)120{121 struct au1xpsc_audio_dmadata *cd = dev_id;122 123 cd->pos += cd->period_bytes;124 if (++cd->curr_period >= cd->periods) {125 cd->pos = 0;126 cd->curr_period = 0;127 }128 snd_pcm_period_elapsed(cd->substream);129 au1x_pcm_queue_rx(cd);130}131 132static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd)133{134 if (pcd->ddma_chan) {135 au1xxx_dbdma_stop(pcd->ddma_chan);136 au1xxx_dbdma_reset(pcd->ddma_chan);137 au1xxx_dbdma_chan_free(pcd->ddma_chan);138 pcd->ddma_chan = 0;139 pcd->msbits = 0;140 }141}142 143/* in case of missing DMA ring or changed TX-source / RX-dest bit widths,144 * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according145 * to ALSA-supplied sample depth. This is due to limitations in the dbdma api146 * (cannot adjust source/dest widths of already allocated descriptor ring).147 */148static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd,149 int stype, int msbits)150{151 /* DMA only in 8/16/32 bit widths */152 if (msbits == 24)153 msbits = 32;154 155 /* check current config: correct bits and descriptors allocated? */156 if ((pcd->ddma_chan) && (msbits == pcd->msbits))157 goto out; /* all ok! */158 159 au1x_pcm_dbdma_free(pcd);160 161 if (stype == SNDRV_PCM_STREAM_CAPTURE)162 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id,163 DSCR_CMD0_ALWAYS,164 au1x_pcm_dmarx_cb, (void *)pcd);165 else166 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS,167 pcd->ddma_id,168 au1x_pcm_dmatx_cb, (void *)pcd);169 170 if (!pcd->ddma_chan)171 return -ENOMEM;172 173 au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits);174 au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2);175 176 pcd->msbits = msbits;177 178 au1xxx_dbdma_stop(pcd->ddma_chan);179 au1xxx_dbdma_reset(pcd->ddma_chan);180 181out:182 return 0;183}184 185static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss,186 struct snd_soc_component *component)187{188 struct au1xpsc_audio_dmadata *pcd = snd_soc_component_get_drvdata(component);189 return &pcd[ss->stream];190}191 192static int au1xpsc_pcm_hw_params(struct snd_soc_component *component,193 struct snd_pcm_substream *substream,194 struct snd_pcm_hw_params *params)195{196 struct snd_pcm_runtime *runtime = substream->runtime;197 struct au1xpsc_audio_dmadata *pcd;198 int stype, ret;199 200 stype = substream->stream;201 pcd = to_dmadata(substream, component);202 203 DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %zu "204 "runtime->min_align %lu\n",205 (unsigned long)runtime->dma_area,206 (unsigned long)runtime->dma_addr, runtime->dma_bytes,207 runtime->min_align);208 209 DBG("bits %d frags %d frag_bytes %d is_rx %d\n", params->msbits,210 params_periods(params), params_period_bytes(params), stype);211 212 ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits);213 if (ret) {214 MSG("DDMA channel (re)alloc failed!\n");215 goto out;216 }217 218 pcd->substream = substream;219 pcd->period_bytes = params_period_bytes(params);220 pcd->periods = params_periods(params);221 pcd->dma_area_s = pcd->dma_area = runtime->dma_addr;222 pcd->q_period = 0;223 pcd->curr_period = 0;224 pcd->pos = 0;225 226 ret = 0;227out:228 return ret;229}230 231static int au1xpsc_pcm_prepare(struct snd_soc_component *component,232 struct snd_pcm_substream *substream)233{234 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);235 236 au1xxx_dbdma_reset(pcd->ddma_chan);237 238 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {239 au1x_pcm_queue_rx(pcd);240 au1x_pcm_queue_rx(pcd);241 } else {242 au1x_pcm_queue_tx(pcd);243 au1x_pcm_queue_tx(pcd);244 }245 246 return 0;247}248 249static int au1xpsc_pcm_trigger(struct snd_soc_component *component,250 struct snd_pcm_substream *substream, int cmd)251{252 u32 c = to_dmadata(substream, component)->ddma_chan;253 254 switch (cmd) {255 case SNDRV_PCM_TRIGGER_START:256 case SNDRV_PCM_TRIGGER_RESUME:257 au1xxx_dbdma_start(c);258 break;259 case SNDRV_PCM_TRIGGER_STOP:260 case SNDRV_PCM_TRIGGER_SUSPEND:261 au1xxx_dbdma_stop(c);262 break;263 default:264 return -EINVAL;265 }266 return 0;267}268 269static snd_pcm_uframes_t270au1xpsc_pcm_pointer(struct snd_soc_component *component,271 struct snd_pcm_substream *substream)272{273 return bytes_to_frames(substream->runtime,274 to_dmadata(substream, component)->pos);275}276 277static int au1xpsc_pcm_open(struct snd_soc_component *component,278 struct snd_pcm_substream *substream)279{280 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);281 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);282 int stype = substream->stream, *dmaids;283 284 dmaids = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);285 if (!dmaids)286 return -ENODEV; /* whoa, has ordering changed? */287 288 pcd->ddma_id = dmaids[stype];289 290 snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware);291 return 0;292}293 294static int au1xpsc_pcm_close(struct snd_soc_component *component,295 struct snd_pcm_substream *substream)296{297 au1x_pcm_dbdma_free(to_dmadata(substream, component));298 return 0;299}300 301static int au1xpsc_pcm_new(struct snd_soc_component *component,302 struct snd_soc_pcm_runtime *rtd)303{304 struct snd_card *card = rtd->card->snd_card;305 struct snd_pcm *pcm = rtd->pcm;306 307 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,308 card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);309 310 return 0;311}312 313/* au1xpsc audio platform */314static struct snd_soc_component_driver au1xpsc_soc_component = {315 .name = DRV_NAME,316 .open = au1xpsc_pcm_open,317 .close = au1xpsc_pcm_close,318 .hw_params = au1xpsc_pcm_hw_params,319 .prepare = au1xpsc_pcm_prepare,320 .trigger = au1xpsc_pcm_trigger,321 .pointer = au1xpsc_pcm_pointer,322 .pcm_construct = au1xpsc_pcm_new,323};324 325static int au1xpsc_pcm_drvprobe(struct platform_device *pdev)326{327 struct au1xpsc_audio_dmadata *dmadata;328 329 dmadata = devm_kcalloc(&pdev->dev,330 2, sizeof(struct au1xpsc_audio_dmadata),331 GFP_KERNEL);332 if (!dmadata)333 return -ENOMEM;334 335 platform_set_drvdata(pdev, dmadata);336 337 return devm_snd_soc_register_component(&pdev->dev,338 &au1xpsc_soc_component, NULL, 0);339}340 341static struct platform_driver au1xpsc_pcm_driver = {342 .driver = {343 .name = "au1xpsc-pcm",344 },345 .probe = au1xpsc_pcm_drvprobe,346};347 348module_platform_driver(au1xpsc_pcm_driver);349 350MODULE_LICENSE("GPL");351MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");352MODULE_AUTHOR("Manuel Lauss");353