diff options
Diffstat (limited to 'sound/soc/au1x/dbdma2.c')
-rw-r--r-- | sound/soc/au1x/dbdma2.c | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/sound/soc/au1x/dbdma2.c b/sound/soc/au1x/dbdma2.c new file mode 100644 index 000000000..dd94fea72 --- /dev/null +++ b/sound/soc/au1x/dbdma2.c @@ -0,0 +1,369 @@ +/* + * Au12x0/Au1550 PSC ALSA ASoC audio support. + * + * (c) 2007-2008 MSC Vertriebsges.m.b.H., + * Manuel Lauss <manuel.lauss@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * DMA glue for Au1x-PSC audio. + * + */ + + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/dma-mapping.h> + +#include <sound/core.h> +#include <sound/pcm.h> +#include <sound/pcm_params.h> +#include <sound/soc.h> + +#include <asm/mach-au1x00/au1000.h> +#include <asm/mach-au1x00/au1xxx_dbdma.h> +#include <asm/mach-au1x00/au1xxx_psc.h> + +#include "psc.h" + +/*#define PCM_DEBUG*/ + +#define MSG(x...) printk(KERN_INFO "au1xpsc_pcm: " x) +#ifdef PCM_DEBUG +#define DBG MSG +#else +#define DBG(x...) do {} while (0) +#endif + +struct au1xpsc_audio_dmadata { + /* DDMA control data */ + unsigned int ddma_id; /* DDMA direction ID for this PSC */ + u32 ddma_chan; /* DDMA context */ + + /* PCM context (for irq handlers) */ + struct snd_pcm_substream *substream; + unsigned long curr_period; /* current segment DDMA is working on */ + unsigned long q_period; /* queue period(s) */ + dma_addr_t dma_area; /* address of queued DMA area */ + dma_addr_t dma_area_s; /* start address of DMA area */ + unsigned long pos; /* current byte position being played */ + unsigned long periods; /* number of SG segments in total */ + unsigned long period_bytes; /* size in bytes of one SG segment */ + + /* runtime data */ + int msbits; +}; + +/* + * These settings are somewhat okay, at least on my machine audio plays + * almost skip-free. Especially the 64kB buffer seems to help a LOT. + */ +#define AU1XPSC_PERIOD_MIN_BYTES 1024 +#define AU1XPSC_BUFFER_MIN_BYTES 65536 + +/* PCM hardware DMA capabilities - platform specific */ +static const struct snd_pcm_hardware au1xpsc_pcm_hardware = { + .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | + SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH, + .period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES, + .period_bytes_max = 4096 * 1024 - 1, + .periods_min = 2, + .periods_max = 4096, /* 2 to as-much-as-you-like */ + .buffer_bytes_max = 4096 * 1024 - 1, + .fifo_size = 16, /* fifo entries of AC97/I2S PSC */ +}; + +static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd) +{ + au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area, + cd->period_bytes, DDMA_FLAGS_IE); + + /* update next-to-queue period */ + ++cd->q_period; + cd->dma_area += cd->period_bytes; + if (cd->q_period >= cd->periods) { + cd->q_period = 0; + cd->dma_area = cd->dma_area_s; + } +} + +static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd) +{ + au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area, + cd->period_bytes, DDMA_FLAGS_IE); + + /* update next-to-queue period */ + ++cd->q_period; + cd->dma_area += cd->period_bytes; + if (cd->q_period >= cd->periods) { + cd->q_period = 0; + cd->dma_area = cd->dma_area_s; + } +} + +static void au1x_pcm_dmatx_cb(int irq, void *dev_id) +{ + struct au1xpsc_audio_dmadata *cd = dev_id; + + cd->pos += cd->period_bytes; + if (++cd->curr_period >= cd->periods) { + cd->pos = 0; + cd->curr_period = 0; + } + snd_pcm_period_elapsed(cd->substream); + au1x_pcm_queue_tx(cd); +} + +static void au1x_pcm_dmarx_cb(int irq, void *dev_id) +{ + struct au1xpsc_audio_dmadata *cd = dev_id; + + cd->pos += cd->period_bytes; + if (++cd->curr_period >= cd->periods) { + cd->pos = 0; + cd->curr_period = 0; + } + snd_pcm_period_elapsed(cd->substream); + au1x_pcm_queue_rx(cd); +} + +static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd) +{ + if (pcd->ddma_chan) { + au1xxx_dbdma_stop(pcd->ddma_chan); + au1xxx_dbdma_reset(pcd->ddma_chan); + au1xxx_dbdma_chan_free(pcd->ddma_chan); + pcd->ddma_chan = 0; + pcd->msbits = 0; + } +} + +/* in case of missing DMA ring or changed TX-source / RX-dest bit widths, + * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according + * to ALSA-supplied sample depth. This is due to limitations in the dbdma api + * (cannot adjust source/dest widths of already allocated descriptor ring). + */ +static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd, + int stype, int msbits) +{ + /* DMA only in 8/16/32 bit widths */ + if (msbits == 24) + msbits = 32; + + /* check current config: correct bits and descriptors allocated? */ + if ((pcd->ddma_chan) && (msbits == pcd->msbits)) + goto out; /* all ok! */ + + au1x_pcm_dbdma_free(pcd); + + if (stype == SNDRV_PCM_STREAM_CAPTURE) + pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id, + DSCR_CMD0_ALWAYS, + au1x_pcm_dmarx_cb, (void *)pcd); + else + pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS, + pcd->ddma_id, + au1x_pcm_dmatx_cb, (void *)pcd); + + if (!pcd->ddma_chan) + return -ENOMEM; + + au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits); + au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2); + + pcd->msbits = msbits; + + au1xxx_dbdma_stop(pcd->ddma_chan); + au1xxx_dbdma_reset(pcd->ddma_chan); + +out: + return 0; +} + +static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss) +{ + struct snd_soc_pcm_runtime *rtd = ss->private_data; + struct au1xpsc_audio_dmadata *pcd = + snd_soc_platform_get_drvdata(rtd->platform); + return &pcd[ss->stream]; +} + +static int au1xpsc_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *params) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct au1xpsc_audio_dmadata *pcd; + int stype, ret; + + ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); + if (ret < 0) + goto out; + + stype = substream->stream; + pcd = to_dmadata(substream); + + DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %d " + "runtime->min_align %d\n", + (unsigned long)runtime->dma_area, + (unsigned long)runtime->dma_addr, runtime->dma_bytes, + runtime->min_align); + + DBG("bits %d frags %d frag_bytes %d is_rx %d\n", params->msbits, + params_periods(params), params_period_bytes(params), stype); + + ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits); + if (ret) { + MSG("DDMA channel (re)alloc failed!\n"); + goto out; + } + + pcd->substream = substream; + pcd->period_bytes = params_period_bytes(params); + pcd->periods = params_periods(params); + pcd->dma_area_s = pcd->dma_area = runtime->dma_addr; + pcd->q_period = 0; + pcd->curr_period = 0; + pcd->pos = 0; + + ret = 0; +out: + return ret; +} + +static int au1xpsc_pcm_hw_free(struct snd_pcm_substream *substream) +{ + snd_pcm_lib_free_pages(substream); + return 0; +} + +static int au1xpsc_pcm_prepare(struct snd_pcm_substream *substream) +{ + struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream); + + au1xxx_dbdma_reset(pcd->ddma_chan); + + if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) { + au1x_pcm_queue_rx(pcd); + au1x_pcm_queue_rx(pcd); + } else { + au1x_pcm_queue_tx(pcd); + au1x_pcm_queue_tx(pcd); + } + + return 0; +} + +static int au1xpsc_pcm_trigger(struct snd_pcm_substream *substream, int cmd) +{ + u32 c = to_dmadata(substream)->ddma_chan; + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + au1xxx_dbdma_start(c); + break; + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + au1xxx_dbdma_stop(c); + break; + default: + return -EINVAL; + } + return 0; +} + +static snd_pcm_uframes_t +au1xpsc_pcm_pointer(struct snd_pcm_substream *substream) +{ + return bytes_to_frames(substream->runtime, to_dmadata(substream)->pos); +} + +static int au1xpsc_pcm_open(struct snd_pcm_substream *substream) +{ + struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream); + struct snd_soc_pcm_runtime *rtd = substream->private_data; + int stype = substream->stream, *dmaids; + + dmaids = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); + if (!dmaids) + return -ENODEV; /* whoa, has ordering changed? */ + + pcd->ddma_id = dmaids[stype]; + + snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware); + return 0; +} + +static int au1xpsc_pcm_close(struct snd_pcm_substream *substream) +{ + au1x_pcm_dbdma_free(to_dmadata(substream)); + return 0; +} + +static struct snd_pcm_ops au1xpsc_pcm_ops = { + .open = au1xpsc_pcm_open, + .close = au1xpsc_pcm_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = au1xpsc_pcm_hw_params, + .hw_free = au1xpsc_pcm_hw_free, + .prepare = au1xpsc_pcm_prepare, + .trigger = au1xpsc_pcm_trigger, + .pointer = au1xpsc_pcm_pointer, +}; + +static int au1xpsc_pcm_new(struct snd_soc_pcm_runtime *rtd) +{ + struct snd_card *card = rtd->card->snd_card; + struct snd_pcm *pcm = rtd->pcm; + + snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, + card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1); + + return 0; +} + +/* au1xpsc audio platform */ +static struct snd_soc_platform_driver au1xpsc_soc_platform = { + .ops = &au1xpsc_pcm_ops, + .pcm_new = au1xpsc_pcm_new, +}; + +static int au1xpsc_pcm_drvprobe(struct platform_device *pdev) +{ + struct au1xpsc_audio_dmadata *dmadata; + + dmadata = devm_kzalloc(&pdev->dev, + 2 * sizeof(struct au1xpsc_audio_dmadata), + GFP_KERNEL); + if (!dmadata) + return -ENOMEM; + + platform_set_drvdata(pdev, dmadata); + + return snd_soc_register_platform(&pdev->dev, &au1xpsc_soc_platform); +} + +static int au1xpsc_pcm_drvremove(struct platform_device *pdev) +{ + snd_soc_unregister_platform(&pdev->dev); + + return 0; +} + +static struct platform_driver au1xpsc_pcm_driver = { + .driver = { + .name = "au1xpsc-pcm", + }, + .probe = au1xpsc_pcm_drvprobe, + .remove = au1xpsc_pcm_drvremove, +}; + +module_platform_driver(au1xpsc_pcm_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver"); +MODULE_AUTHOR("Manuel Lauss"); |