1 files changed, 352 insertions, 0 deletions
diff --git a/sound/soc/au1x/dbdma2.c b/sound/soc/au1x/dbdma2.c
new file mode 100644
index 000000000..3d67e27fa
--- /dev/null
+++ b/sound/soc/au1x/dbdma2.c
@@ -0,0 +1,352 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Au12x0/Au1550 PSC ALSA ASoC audio support.
+ *
+ * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
+ *	Manuel Lauss <manuel.lauss@gmail.com>
+ *
+ * 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 DRV_NAME "dbdma2"
+
+#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_component *component)
+{
+	struct au1xpsc_audio_dmadata *pcd = snd_soc_component_get_drvdata(component);
+	return &pcd[ss->stream];
+}
+
+static int au1xpsc_pcm_hw_params(struct snd_soc_component *component,
+				 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;
+
+	stype = substream->stream;
+	pcd = to_dmadata(substream, component);
+
+	DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %zu "
+	    "runtime->min_align %lu\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_prepare(struct snd_soc_component *component,
+			       struct snd_pcm_substream *substream)
+{
+	struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);
+
+	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_soc_component *component,
+			       struct snd_pcm_substream *substream, int cmd)
+{
+	u32 c = to_dmadata(substream, component)->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_soc_component *component,
+		    struct snd_pcm_substream *substream)
+{
+	return bytes_to_frames(substream->runtime,
+			       to_dmadata(substream, component)->pos);
+}
+
+static int au1xpsc_pcm_open(struct snd_soc_component *component,
+			    struct snd_pcm_substream *substream)
+{
+	struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream, component);
+	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+	int stype = substream->stream, *dmaids;
+
+	dmaids = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), 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_soc_component *component,
+			     struct snd_pcm_substream *substream)
+{
+	au1x_pcm_dbdma_free(to_dmadata(substream, component));
+	return 0;
+}
+
+static int au1xpsc_pcm_new(struct snd_soc_component *component,
+			   struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_card *card = rtd->card->snd_card;
+	struct snd_pcm *pcm = rtd->pcm;
+
+	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
+		card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);
+
+	return 0;
+}
+
+/* au1xpsc audio platform */
+static struct snd_soc_component_driver au1xpsc_soc_component = {
+	.name		= DRV_NAME,
+	.open		= au1xpsc_pcm_open,
+	.close		= au1xpsc_pcm_close,
+	.hw_params	= au1xpsc_pcm_hw_params,
+	.prepare	= au1xpsc_pcm_prepare,
+	.trigger	= au1xpsc_pcm_trigger,
+	.pointer	= au1xpsc_pcm_pointer,
+	.pcm_construct	= au1xpsc_pcm_new,
+};
+
+static int au1xpsc_pcm_drvprobe(struct platform_device *pdev)
+{
+	struct au1xpsc_audio_dmadata *dmadata;
+
+	dmadata = devm_kcalloc(&pdev->dev,
+			       2, sizeof(struct au1xpsc_audio_dmadata),
+			       GFP_KERNEL);
+	if (!dmadata)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, dmadata);
+
+	return devm_snd_soc_register_component(&pdev->dev,
+					&au1xpsc_soc_component, NULL, 0);
+}
+
+static struct platform_driver au1xpsc_pcm_driver = {
+	.driver	= {
+		.name	= "au1xpsc-pcm",
+	},
+	.probe		= au1xpsc_pcm_drvprobe,
+};
+
+module_platform_driver(au1xpsc_pcm_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
+MODULE_AUTHOR("Manuel Lauss");