ASoC: Basic split of mpc5200 DMA code out of mpc5200_psc_i2s

Basic split of mpc5200 DMA code out from i2s into a standalone file.

Signed-off-by: Jon Smirl <jonsmirl@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/fsl/mpc5200_dma.c b/sound/soc/fsl/mpc5200_dma.c
new file mode 100644
index 0000000..4bae8d6
--- /dev/null
+++ b/sound/soc/fsl/mpc5200_dma.c
@@ -0,0 +1,458 @@
+/*
+ * Freescale MPC5200 PSC DMA
+ * ALSA SoC Platform driver
+ *
+ * Copyright (C) 2008 Secret Lab Technologies Ltd.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/dma-mapping.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+#include <sound/soc-of-simple.h>
+
+#include <sysdev/bestcomm/bestcomm.h>
+#include <sysdev/bestcomm/gen_bd.h>
+#include <asm/mpc52xx_psc.h>
+
+#include "mpc5200_dma.h"
+
+MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
+MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
+MODULE_LICENSE("GPL");
+
+/*
+ * Interrupt handlers
+ */
+static irqreturn_t psc_i2s_status_irq(int irq, void *_psc_i2s)
+{
+	struct psc_i2s *psc_i2s = _psc_i2s;
+	struct mpc52xx_psc __iomem *regs = psc_i2s->psc_regs;
+	u16 isr;
+
+	isr = in_be16(&regs->mpc52xx_psc_isr);
+
+	/* Playback underrun error */
+	if (psc_i2s->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
+		psc_i2s->stats.underrun_count++;
+
+	/* Capture overrun error */
+	if (psc_i2s->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
+		psc_i2s->stats.overrun_count++;
+
+	out_8(&regs->command, 4 << 4);	/* reset the error status */
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * psc_i2s_bcom_enqueue_next_buffer - Enqueue another audio buffer
+ * @s: pointer to stream private data structure
+ *
+ * Enqueues another audio period buffer into the bestcomm queue.
+ *
+ * Note: The routine must only be called when there is space available in
+ * the queue.  Otherwise the enqueue will fail and the audio ring buffer
+ * will get out of sync
+ */
+static void psc_i2s_bcom_enqueue_next_buffer(struct psc_i2s_stream *s)
+{
+	struct bcom_bd *bd;
+
+	/* Prepare and enqueue the next buffer descriptor */
+	bd = bcom_prepare_next_buffer(s->bcom_task);
+	bd->status = s->period_bytes;
+	bd->data[0] = s->period_next_pt;
+	bcom_submit_next_buffer(s->bcom_task, NULL);
+
+	/* Update for next period */
+	s->period_next_pt += s->period_bytes;
+	if (s->period_next_pt >= s->period_end)
+		s->period_next_pt = s->period_start;
+}
+
+/* Bestcomm DMA irq handler */
+static irqreturn_t psc_i2s_bcom_irq(int irq, void *_psc_i2s_stream)
+{
+	struct psc_i2s_stream *s = _psc_i2s_stream;
+
+	/* For each finished period, dequeue the completed period buffer
+	 * and enqueue a new one in it's place. */
+	while (bcom_buffer_done(s->bcom_task)) {
+		bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
+		s->period_current_pt += s->period_bytes;
+		if (s->period_current_pt >= s->period_end)
+			s->period_current_pt = s->period_start;
+		psc_i2s_bcom_enqueue_next_buffer(s);
+		bcom_enable(s->bcom_task);
+	}
+
+	/* If the stream is active, then also inform the PCM middle layer
+	 * of the period finished event. */
+	if (s->active)
+		snd_pcm_period_elapsed(s->stream);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * psc_i2s_startup: create a new substream
+ *
+ * This is the first function called when a stream is opened.
+ *
+ * If this is the first stream open, then grab the IRQ and program most of
+ * the PSC registers.
+ */
+int psc_i2s_startup(struct snd_pcm_substream *substream,
+			   struct snd_soc_dai *dai)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+	int rc;
+
+	dev_dbg(psc_i2s->dev, "psc_i2s_startup(substream=%p)\n", substream);
+
+	if (!psc_i2s->playback.active &&
+	    !psc_i2s->capture.active) {
+		/* Setup the IRQs */
+		rc = request_irq(psc_i2s->irq, &psc_i2s_status_irq, IRQF_SHARED,
+				 "psc-i2s-status", psc_i2s);
+		rc |= request_irq(psc_i2s->capture.irq,
+				  &psc_i2s_bcom_irq, IRQF_SHARED,
+				  "psc-i2s-capture", &psc_i2s->capture);
+		rc |= request_irq(psc_i2s->playback.irq,
+				  &psc_i2s_bcom_irq, IRQF_SHARED,
+				  "psc-i2s-playback", &psc_i2s->playback);
+		if (rc) {
+			free_irq(psc_i2s->irq, psc_i2s);
+			free_irq(psc_i2s->capture.irq,
+				 &psc_i2s->capture);
+			free_irq(psc_i2s->playback.irq,
+				 &psc_i2s->playback);
+			return -ENODEV;
+		}
+	}
+
+	return 0;
+}
+
+int psc_i2s_hw_free(struct snd_pcm_substream *substream,
+			   struct snd_soc_dai *dai)
+{
+	snd_pcm_set_runtime_buffer(substream, NULL);
+	return 0;
+}
+
+/**
+ * psc_i2s_trigger: start and stop the DMA transfer.
+ *
+ * This function is called by ALSA to start, stop, pause, and resume the DMA
+ * transfer of data.
+ */
+int psc_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
+			   struct snd_soc_dai *dai)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct psc_i2s_stream *s;
+	struct mpc52xx_psc __iomem *regs = psc_i2s->psc_regs;
+	u16 imr;
+	u8 psc_cmd;
+	unsigned long flags;
+
+	if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+		s = &psc_i2s->capture;
+	else
+		s = &psc_i2s->playback;
+
+	dev_dbg(psc_i2s->dev, "psc_i2s_trigger(substream=%p, cmd=%i)"
+		" stream_id=%i\n",
+		substream, cmd, substream->pstr->stream);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		s->period_bytes = frames_to_bytes(runtime,
+						  runtime->period_size);
+		s->period_start = virt_to_phys(runtime->dma_area);
+		s->period_end = s->period_start +
+				(s->period_bytes * runtime->periods);
+		s->period_next_pt = s->period_start;
+		s->period_current_pt = s->period_start;
+		s->active = 1;
+
+		/* First; reset everything */
+		if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) {
+			out_8(&regs->command, MPC52xx_PSC_RST_RX);
+			out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
+		} else {
+			out_8(&regs->command, MPC52xx_PSC_RST_TX);
+			out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
+		}
+
+		/* Next, fill up the bestcomm bd queue and enable DMA.
+		 * This will begin filling the PSC's fifo. */
+		if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+			bcom_gen_bd_rx_reset(s->bcom_task);
+		else
+			bcom_gen_bd_tx_reset(s->bcom_task);
+		while (!bcom_queue_full(s->bcom_task))
+			psc_i2s_bcom_enqueue_next_buffer(s);
+		bcom_enable(s->bcom_task);
+
+		/* Due to errata in the i2s mode; need to line up enabling
+		 * the transmitter with a transition on the frame sync
+		 * line */
+
+		spin_lock_irqsave(&psc_i2s->lock, flags);
+		/* first make sure it is low */
+		while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
+			;
+		/* then wait for the transition to high */
+		while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
+			;
+		/* Finally, enable the PSC.
+		 * Receiver must always be enabled; even when we only want
+		 * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */
+		psc_cmd = MPC52xx_PSC_RX_ENABLE;
+		if (substream->pstr->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			psc_cmd |= MPC52xx_PSC_TX_ENABLE;
+		out_8(&regs->command, psc_cmd);
+		spin_unlock_irqrestore(&psc_i2s->lock, flags);
+
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+		/* Turn off the PSC */
+		s->active = 0;
+		if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) {
+			if (!psc_i2s->playback.active) {
+				out_8(&regs->command, 2 << 4);	/* reset rx */
+				out_8(&regs->command, 3 << 4);	/* reset tx */
+				out_8(&regs->command, 4 << 4);	/* reset err */
+			}
+		} else {
+			out_8(&regs->command, 3 << 4);	/* reset tx */
+			out_8(&regs->command, 4 << 4);	/* reset err */
+			if (!psc_i2s->capture.active)
+				out_8(&regs->command, 2 << 4);	/* reset rx */
+		}
+
+		bcom_disable(s->bcom_task);
+		while (!bcom_queue_empty(s->bcom_task))
+			bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
+
+		break;
+
+	default:
+		dev_dbg(psc_i2s->dev, "invalid command\n");
+		return -EINVAL;
+	}
+
+	/* Update interrupt enable settings */
+	imr = 0;
+	if (psc_i2s->playback.active)
+		imr |= MPC52xx_PSC_IMR_TXEMP;
+	if (psc_i2s->capture.active)
+		imr |= MPC52xx_PSC_IMR_ORERR;
+	out_be16(&regs->isr_imr.imr, imr);
+
+	return 0;
+}
+
+/**
+ * psc_i2s_shutdown: shutdown the data transfer on a stream
+ *
+ * Shutdown the PSC if there are no other substreams open.
+ */
+void psc_i2s_shutdown(struct snd_pcm_substream *substream,
+			     struct snd_soc_dai *dai)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+
+	dev_dbg(psc_i2s->dev, "psc_i2s_shutdown(substream=%p)\n", substream);
+
+	/*
+	 * If this is the last active substream, disable the PSC and release
+	 * the IRQ.
+	 */
+	if (!psc_i2s->playback.active &&
+	    !psc_i2s->capture.active) {
+
+		/* Disable all interrupts and reset the PSC */
+		out_be16(&psc_i2s->psc_regs->isr_imr.imr, 0);
+		out_8(&psc_i2s->psc_regs->command, 3 << 4); /* reset tx */
+		out_8(&psc_i2s->psc_regs->command, 2 << 4); /* reset rx */
+		out_8(&psc_i2s->psc_regs->command, 1 << 4); /* reset mode */
+		out_8(&psc_i2s->psc_regs->command, 4 << 4); /* reset error */
+
+		/* Release irqs */
+		free_irq(psc_i2s->irq, psc_i2s);
+		free_irq(psc_i2s->capture.irq, &psc_i2s->capture);
+		free_irq(psc_i2s->playback.irq, &psc_i2s->playback);
+	}
+}
+
+/* ---------------------------------------------------------------------
+ * The PSC DMA 'ASoC platform' driver
+ *
+ * Can be referenced by an 'ASoC machine' driver
+ * This driver only deals with the audio bus; it doesn't have any
+ * interaction with the attached codec
+ */
+
+static const struct snd_pcm_hardware psc_i2s_pcm_hardware = {
+	.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+		SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
+		SNDRV_PCM_INFO_BATCH,
+	.formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
+		   SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
+	.rate_min = 8000,
+	.rate_max = 48000,
+	.channels_min = 2,
+	.channels_max = 2,
+	.period_bytes_max	= 1024 * 1024,
+	.period_bytes_min	= 32,
+	.periods_min		= 2,
+	.periods_max		= 256,
+	.buffer_bytes_max	= 2 * 1024 * 1024,
+	.fifo_size		= 0,
+};
+
+static int psc_i2s_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+	struct psc_i2s_stream *s;
+
+	dev_dbg(psc_i2s->dev, "psc_i2s_pcm_open(substream=%p)\n", substream);
+
+	if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+		s = &psc_i2s->capture;
+	else
+		s = &psc_i2s->playback;
+
+	snd_soc_set_runtime_hwparams(substream, &psc_i2s_pcm_hardware);
+
+	s->stream = substream;
+	return 0;
+}
+
+static int psc_i2s_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+	struct psc_i2s_stream *s;
+
+	dev_dbg(psc_i2s->dev, "psc_i2s_pcm_close(substream=%p)\n", substream);
+
+	if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+		s = &psc_i2s->capture;
+	else
+		s = &psc_i2s->playback;
+
+	s->stream = NULL;
+	return 0;
+}
+
+static snd_pcm_uframes_t
+psc_i2s_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+	struct psc_i2s_stream *s;
+	dma_addr_t count;
+
+	if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+		s = &psc_i2s->capture;
+	else
+		s = &psc_i2s->playback;
+
+	count = s->period_current_pt - s->period_start;
+
+	return bytes_to_frames(substream->runtime, count);
+}
+
+static struct snd_pcm_ops psc_i2s_pcm_ops = {
+	.open		= psc_i2s_pcm_open,
+	.close		= psc_i2s_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.pointer	= psc_i2s_pcm_pointer,
+};
+
+static u64 psc_i2s_pcm_dmamask = 0xffffffff;
+static int psc_i2s_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
+			   struct snd_pcm *pcm)
+{
+	struct snd_soc_pcm_runtime *rtd = pcm->private_data;
+	size_t size = psc_i2s_pcm_hardware.buffer_bytes_max;
+	int rc = 0;
+
+	dev_dbg(rtd->socdev->dev, "psc_i2s_pcm_new(card=%p, dai=%p, pcm=%p)\n",
+		card, dai, pcm);
+
+	if (!card->dev->dma_mask)
+		card->dev->dma_mask = &psc_i2s_pcm_dmamask;
+	if (!card->dev->coherent_dma_mask)
+		card->dev->coherent_dma_mask = 0xffffffff;
+
+	if (pcm->streams[0].substream) {
+		rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->dev, size,
+					&pcm->streams[0].substream->dma_buffer);
+		if (rc)
+			goto playback_alloc_err;
+	}
+
+	if (pcm->streams[1].substream) {
+		rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->dev, size,
+					&pcm->streams[1].substream->dma_buffer);
+		if (rc)
+			goto capture_alloc_err;
+	}
+
+	return 0;
+
+ capture_alloc_err:
+	if (pcm->streams[0].substream)
+		snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer);
+ playback_alloc_err:
+	dev_err(card->dev, "Cannot allocate buffer(s)\n");
+	return -ENOMEM;
+}
+
+static void psc_i2s_pcm_free(struct snd_pcm *pcm)
+{
+	struct snd_soc_pcm_runtime *rtd = pcm->private_data;
+	struct snd_pcm_substream *substream;
+	int stream;
+
+	dev_dbg(rtd->socdev->dev, "psc_i2s_pcm_free(pcm=%p)\n", pcm);
+
+	for (stream = 0; stream < 2; stream++) {
+		substream = pcm->streams[stream].substream;
+		if (substream) {
+			snd_dma_free_pages(&substream->dma_buffer);
+			substream->dma_buffer.area = NULL;
+			substream->dma_buffer.addr = 0;
+		}
+	}
+}
+
+struct snd_soc_platform psc_i2s_pcm_soc_platform = {
+	.name		= "mpc5200-psc-audio",
+	.pcm_ops	= &psc_i2s_pcm_ops,
+	.pcm_new	= &psc_i2s_pcm_new,
+	.pcm_free	= &psc_i2s_pcm_free,
+};
+