ASoC: add DAI and platform / DMA drivers for SH SIU

Several SuperH platforms, including sh7722, sh7343, sh7354, sh7367 include
a Sound Interface Unit (SIU). This patch adds DAI and platform / DMA
drivers for this interface.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/sh/siu_pcm.c b/sound/soc/sh/siu_pcm.c
new file mode 100644
index 0000000..c5efc30
--- /dev/null
+++ b/sound/soc/sh/siu_pcm.c
@@ -0,0 +1,616 @@
+/*
+ * siu_pcm.c - ALSA driver for Renesas SH7343, SH7722 SIU peripheral.
+ *
+ * Copyright (C) 2009-2010 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ * Copyright (C) 2006 Carlos Munoz <carlos@kenati.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <sound/control.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc-dai.h>
+
+#include <asm/dma-sh.h>
+#include <asm/siu.h>
+
+#include "siu.h"
+
+#define GET_MAX_PERIODS(buf_bytes, period_bytes) \
+				((buf_bytes) / (period_bytes))
+#define PERIOD_OFFSET(buf_addr, period_num, period_bytes) \
+				((buf_addr) + ((period_num) * (period_bytes)))
+
+#define RWF_STM_RD		0x01		/* Read in progress */
+#define RWF_STM_WT		0x02		/* Write in progress */
+
+struct siu_port *siu_ports[SIU_PORT_NUM];
+
+/* transfersize is number of u32 dma transfers per period */
+static int siu_pcm_stmwrite_stop(struct siu_port *port_info)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	u32 __iomem *base = info->reg;
+	struct siu_stream *siu_stream = &port_info->playback;
+	u32 stfifo;
+
+	if (!siu_stream->rw_flg)
+		return -EPERM;
+
+	/* output FIFO disable */
+	stfifo = siu_read32(base + SIU_STFIFO);
+	siu_write32(base + SIU_STFIFO, stfifo & ~0x0c180c18);
+	pr_debug("%s: STFIFO %x -> %x\n", __func__,
+		 stfifo, stfifo & ~0x0c180c18);
+
+	/* during stmwrite clear */
+	siu_stream->rw_flg = 0;
+
+	return 0;
+}
+
+static int siu_pcm_stmwrite_start(struct siu_port *port_info)
+{
+	struct siu_stream *siu_stream = &port_info->playback;
+
+	if (siu_stream->rw_flg)
+		return -EPERM;
+
+	/* Current period in buffer */
+	port_info->playback.cur_period = 0;
+
+	/* during stmwrite flag set */
+	siu_stream->rw_flg = RWF_STM_WT;
+
+	/* DMA transfer start */
+	tasklet_schedule(&siu_stream->tasklet);
+
+	return 0;
+}
+
+static void siu_dma_tx_complete(void *arg)
+{
+	struct siu_stream *siu_stream = arg;
+
+	if (!siu_stream->rw_flg)
+		return;
+
+	/* Update completed period count */
+	if (++siu_stream->cur_period >=
+	    GET_MAX_PERIODS(siu_stream->buf_bytes,
+			    siu_stream->period_bytes))
+		siu_stream->cur_period = 0;
+
+	pr_debug("%s: done period #%d (%u/%u bytes), cookie %d\n",
+		__func__, siu_stream->cur_period,
+		siu_stream->cur_period * siu_stream->period_bytes,
+		siu_stream->buf_bytes, siu_stream->cookie);
+
+	tasklet_schedule(&siu_stream->tasklet);
+
+	/* Notify alsa: a period is done */
+	snd_pcm_period_elapsed(siu_stream->substream);
+}
+
+static int siu_pcm_wr_set(struct siu_port *port_info,
+			  dma_addr_t buff, u32 size)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	u32 __iomem *base = info->reg;
+	struct siu_stream *siu_stream = &port_info->playback;
+	struct snd_pcm_substream *substream = siu_stream->substream;
+	struct device *dev = substream->pcm->card->dev;
+	struct dma_async_tx_descriptor *desc;
+	dma_cookie_t cookie;
+	struct scatterlist sg;
+	u32 stfifo;
+
+	sg_init_table(&sg, 1);
+	sg_set_page(&sg, pfn_to_page(PFN_DOWN(buff)),
+		    size, offset_in_page(buff));
+	sg_dma_address(&sg) = buff;
+
+	desc = siu_stream->chan->device->device_prep_slave_sg(siu_stream->chan,
+		&sg, 1, DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!desc) {
+		dev_err(dev, "Failed to allocate a dma descriptor\n");
+		return -ENOMEM;
+	}
+
+	desc->callback = siu_dma_tx_complete;
+	desc->callback_param = siu_stream;
+	cookie = desc->tx_submit(desc);
+	if (cookie < 0) {
+		dev_err(dev, "Failed to submit a dma transfer\n");
+		return cookie;
+	}
+
+	siu_stream->tx_desc = desc;
+	siu_stream->cookie = cookie;
+
+	dma_async_issue_pending(siu_stream->chan);
+
+	/* only output FIFO enable */
+	stfifo = siu_read32(base + SIU_STFIFO);
+	siu_write32(base + SIU_STFIFO, stfifo | (port_info->stfifo & 0x0c180c18));
+	dev_dbg(dev, "%s: STFIFO %x -> %x\n", __func__,
+		stfifo, stfifo | (port_info->stfifo & 0x0c180c18));
+
+	return 0;
+}
+
+static int siu_pcm_rd_set(struct siu_port *port_info,
+			  dma_addr_t buff, size_t size)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	u32 __iomem *base = info->reg;
+	struct siu_stream *siu_stream = &port_info->capture;
+	struct snd_pcm_substream *substream = siu_stream->substream;
+	struct device *dev = substream->pcm->card->dev;
+	struct dma_async_tx_descriptor *desc;
+	dma_cookie_t cookie;
+	struct scatterlist sg;
+	u32 stfifo;
+
+	dev_dbg(dev, "%s: %u@%llx\n", __func__, size, (unsigned long long)buff);
+
+	sg_init_table(&sg, 1);
+	sg_set_page(&sg, pfn_to_page(PFN_DOWN(buff)),
+		    size, offset_in_page(buff));
+	sg_dma_address(&sg) = buff;
+
+	desc = siu_stream->chan->device->device_prep_slave_sg(siu_stream->chan,
+		&sg, 1, DMA_FROM_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!desc) {
+		dev_err(dev, "Failed to allocate dma descriptor\n");
+		return -ENOMEM;
+	}
+
+	desc->callback = siu_dma_tx_complete;
+	desc->callback_param = siu_stream;
+	cookie = desc->tx_submit(desc);
+	if (cookie < 0) {
+		dev_err(dev, "Failed to submit dma descriptor\n");
+		return cookie;
+	}
+
+	siu_stream->tx_desc = desc;
+	siu_stream->cookie = cookie;
+
+	dma_async_issue_pending(siu_stream->chan);
+
+	/* only input FIFO enable */
+	stfifo = siu_read32(base + SIU_STFIFO);
+	siu_write32(base + SIU_STFIFO, siu_read32(base + SIU_STFIFO) |
+		    (port_info->stfifo & 0x13071307));
+	dev_dbg(dev, "%s: STFIFO %x -> %x\n", __func__,
+		stfifo, stfifo | (port_info->stfifo & 0x13071307));
+
+	return 0;
+}
+
+static void siu_io_tasklet(unsigned long data)
+{
+	struct siu_stream *siu_stream = (struct siu_stream *)data;
+	struct snd_pcm_substream *substream = siu_stream->substream;
+	struct device *dev = substream->pcm->card->dev;
+	struct snd_pcm_runtime *rt = substream->runtime;
+	struct siu_port *port_info = siu_port_info(substream);
+
+	dev_dbg(dev, "%s: flags %x\n", __func__, siu_stream->rw_flg);
+
+	if (!siu_stream->rw_flg) {
+		dev_dbg(dev, "%s: stream inactive\n", __func__);
+		return;
+	}
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
+		dma_addr_t buff;
+		size_t count;
+		u8 *virt;
+
+		buff = (dma_addr_t)PERIOD_OFFSET(rt->dma_addr,
+						siu_stream->cur_period,
+						siu_stream->period_bytes);
+		virt = PERIOD_OFFSET(rt->dma_area,
+				     siu_stream->cur_period,
+				     siu_stream->period_bytes);
+		count = siu_stream->period_bytes;
+
+		/* DMA transfer start */
+		siu_pcm_rd_set(port_info, buff, count);
+	} else {
+		siu_pcm_wr_set(port_info,
+			       (dma_addr_t)PERIOD_OFFSET(rt->dma_addr,
+						siu_stream->cur_period,
+						siu_stream->period_bytes),
+			       siu_stream->period_bytes);
+	}
+}
+
+/* Capture */
+static int siu_pcm_stmread_start(struct siu_port *port_info)
+{
+	struct siu_stream *siu_stream = &port_info->capture;
+
+	if (siu_stream->xfer_cnt > 0x1000000)
+		return -EINVAL;
+	if (siu_stream->rw_flg)
+		return -EPERM;
+
+	/* Current period in buffer */
+	siu_stream->cur_period = 0;
+
+	/* during stmread flag set */
+	siu_stream->rw_flg = RWF_STM_RD;
+
+	tasklet_schedule(&siu_stream->tasklet);
+
+	return 0;
+}
+
+static int siu_pcm_stmread_stop(struct siu_port *port_info)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	u32 __iomem *base = info->reg;
+	struct siu_stream *siu_stream = &port_info->capture;
+	struct device *dev = siu_stream->substream->pcm->card->dev;
+	u32 stfifo;
+
+	if (!siu_stream->rw_flg)
+		return -EPERM;
+
+	/* input FIFO disable */
+	stfifo = siu_read32(base + SIU_STFIFO);
+	siu_write32(base + SIU_STFIFO, stfifo & ~0x13071307);
+	dev_dbg(dev, "%s: STFIFO %x -> %x\n", __func__,
+		stfifo, stfifo & ~0x13071307);
+
+	/* during stmread flag clear */
+	siu_stream->rw_flg = 0;
+
+	return 0;
+}
+
+static int siu_pcm_hw_params(struct snd_pcm_substream *ss,
+			     struct snd_pcm_hw_params *hw_params)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	struct device *dev = ss->pcm->card->dev;
+	int ret;
+
+	dev_dbg(dev, "%s: port=%d\n", __func__, info->port_id);
+
+	ret = snd_pcm_lib_malloc_pages(ss, params_buffer_bytes(hw_params));
+	if (ret < 0)
+		dev_err(dev, "snd_pcm_lib_malloc_pages() failed\n");
+
+	return ret;
+}
+
+static int siu_pcm_hw_free(struct snd_pcm_substream *ss)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	struct siu_port	*port_info = siu_port_info(ss);
+	struct device *dev = ss->pcm->card->dev;
+	struct siu_stream *siu_stream;
+
+	if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		siu_stream = &port_info->playback;
+	else
+		siu_stream = &port_info->capture;
+
+	dev_dbg(dev, "%s: port=%d\n", __func__, info->port_id);
+
+	return snd_pcm_lib_free_pages(ss);
+}
+
+static bool filter(struct dma_chan *chan, void *slave)
+{
+	struct sh_dmae_slave *param = slave;
+
+	pr_debug("%s: slave ID %d\n", __func__, param->slave_id);
+
+	if (unlikely(param->dma_dev != chan->device->dev))
+		return false;
+
+	chan->private = param;
+	return true;
+}
+
+static int siu_pcm_open(struct snd_pcm_substream *ss)
+{
+	/* Playback / Capture */
+	struct siu_info *info = siu_i2s_dai.private_data;
+	struct siu_port *port_info = siu_port_info(ss);
+	struct siu_stream *siu_stream;
+	u32 port = info->port_id;
+	struct siu_platform *pdata = siu_i2s_dai.dev->platform_data;
+	struct device *dev = ss->pcm->card->dev;
+	dma_cap_mask_t mask;
+	struct sh_dmae_slave *param;
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+
+	dev_dbg(dev, "%s, port=%d@%p\n", __func__, port, port_info);
+
+	if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		siu_stream = &port_info->playback;
+		param = &siu_stream->param;
+		param->slave_id = port ? SHDMA_SLAVE_SIUB_TX :
+			SHDMA_SLAVE_SIUA_TX;
+	} else {
+		siu_stream = &port_info->capture;
+		param = &siu_stream->param;
+		param->slave_id = port ? SHDMA_SLAVE_SIUB_RX :
+			SHDMA_SLAVE_SIUA_RX;
+	}
+
+	param->dma_dev = pdata->dma_dev;
+	/* Get DMA channel */
+	siu_stream->chan = dma_request_channel(mask, filter, param);
+	if (!siu_stream->chan) {
+		dev_err(dev, "DMA channel allocation failed!\n");
+		return -EBUSY;
+	}
+
+	siu_stream->substream = ss;
+
+	return 0;
+}
+
+static int siu_pcm_close(struct snd_pcm_substream *ss)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	struct device *dev = ss->pcm->card->dev;
+	struct siu_port *port_info = siu_port_info(ss);
+	struct siu_stream *siu_stream;
+
+	dev_dbg(dev, "%s: port=%d\n", __func__, info->port_id);
+
+	if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		siu_stream = &port_info->playback;
+	else
+		siu_stream = &port_info->capture;
+
+	dma_release_channel(siu_stream->chan);
+	siu_stream->chan = NULL;
+
+	siu_stream->substream = NULL;
+
+	return 0;
+}
+
+static int siu_pcm_prepare(struct snd_pcm_substream *ss)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	struct siu_port *port_info = siu_port_info(ss);
+	struct device *dev = ss->pcm->card->dev;
+	struct snd_pcm_runtime 	*rt = ss->runtime;
+	struct siu_stream *siu_stream;
+	snd_pcm_sframes_t xfer_cnt;
+
+	if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		siu_stream = &port_info->playback;
+	else
+		siu_stream = &port_info->capture;
+
+	rt = siu_stream->substream->runtime;
+
+	siu_stream->buf_bytes = snd_pcm_lib_buffer_bytes(ss);
+	siu_stream->period_bytes = snd_pcm_lib_period_bytes(ss);
+
+	dev_dbg(dev, "%s: port=%d, %d channels, period=%u bytes\n", __func__,
+		info->port_id, rt->channels, siu_stream->period_bytes);
+
+	/* We only support buffers that are multiples of the period */
+	if (siu_stream->buf_bytes % siu_stream->period_bytes) {
+		dev_err(dev, "%s() - buffer=%d not multiple of period=%d\n",
+		       __func__, siu_stream->buf_bytes,
+		       siu_stream->period_bytes);
+		return -EINVAL;
+	}
+
+	xfer_cnt = bytes_to_frames(rt, siu_stream->period_bytes);
+	if (!xfer_cnt || xfer_cnt > 0x1000000)
+		return -EINVAL;
+
+	siu_stream->format = rt->format;
+	siu_stream->xfer_cnt = xfer_cnt;
+
+	dev_dbg(dev, "port=%d buf=%lx buf_bytes=%d period_bytes=%d "
+		"format=%d channels=%d xfer_cnt=%d\n", info->port_id,
+		(unsigned long)rt->dma_addr, siu_stream->buf_bytes,
+		siu_stream->period_bytes,
+		siu_stream->format, rt->channels, (int)xfer_cnt);
+
+	return 0;
+}
+
+static int siu_pcm_trigger(struct snd_pcm_substream *ss, int cmd)
+{
+	struct siu_info *info = siu_i2s_dai.private_data;
+	struct device *dev = ss->pcm->card->dev;
+	struct siu_port *port_info = siu_port_info(ss);
+	int ret;
+
+	dev_dbg(dev, "%s: port=%d@%p, cmd=%d\n", __func__,
+		info->port_id, port_info, cmd);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			ret = siu_pcm_stmwrite_start(port_info);
+		else
+			ret = siu_pcm_stmread_start(port_info);
+
+		if (ret < 0)
+			dev_warn(dev, "%s: start failed on port=%d\n",
+				 __func__, info->port_id);
+
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			siu_pcm_stmwrite_stop(port_info);
+		else
+			siu_pcm_stmread_stop(port_info);
+		ret = 0;
+
+		break;
+	default:
+		dev_err(dev, "%s() unsupported cmd=%d\n", __func__, cmd);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+/*
+ * So far only resolution of one period is supported, subject to extending the
+ * dmangine API
+ */
+static snd_pcm_uframes_t siu_pcm_pointer_dma(struct snd_pcm_substream *ss)
+{
+	struct device *dev = ss->pcm->card->dev;
+	struct siu_info *info = siu_i2s_dai.private_data;
+	u32 __iomem *base = info->reg;
+	struct siu_port *port_info = siu_port_info(ss);
+	struct snd_pcm_runtime *rt = ss->runtime;
+	size_t ptr;
+	struct siu_stream *siu_stream;
+
+	if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		siu_stream = &port_info->playback;
+	else
+		siu_stream = &port_info->capture;
+
+	/*
+	 * ptr is the offset into the buffer where the dma is currently at. We
+	 * check if the dma buffer has just wrapped.
+	 */
+	ptr = PERIOD_OFFSET(rt->dma_addr,
+			    siu_stream->cur_period,
+			    siu_stream->period_bytes) - rt->dma_addr;
+
+	dev_dbg(dev,
+		"%s: port=%d, events %x, FSTS %x, xferred %u/%u, cookie %d\n",
+		__func__, info->port_id, siu_read32(base + SIU_EVNTC),
+		siu_read32(base + SIU_SBFSTS), ptr, siu_stream->buf_bytes,
+		siu_stream->cookie);
+
+	if (ptr >= siu_stream->buf_bytes)
+		ptr = 0;
+
+	return bytes_to_frames(ss->runtime, ptr);
+}
+
+static int siu_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
+		       struct snd_pcm *pcm)
+{
+	/* card->dev == socdev->dev, see snd_soc_new_pcms() */
+	struct siu_info *info = siu_i2s_dai.private_data;
+	struct platform_device *pdev = to_platform_device(card->dev);
+	int ret;
+	int i;
+
+	/* pdev->id selects between SIUA and SIUB */
+	if (pdev->id < 0 || pdev->id >= SIU_PORT_NUM)
+		return -EINVAL;
+
+	info->port_id = pdev->id;
+
+	/*
+	 * While the siu has 2 ports, only one port can be on at a time (only 1
+	 * SPB). So far all the boards using the siu had only one of the ports
+	 * wired to a codec. To simplify things, we only register one port with
+	 * alsa. In case both ports are needed, it should be changed here
+	 */
+	for (i = pdev->id; i < pdev->id + 1; i++) {
+		struct siu_port **port_info = &siu_ports[i];
+
+		ret = siu_init_port(i, port_info, card);
+		if (ret < 0)
+			return ret;
+
+		ret = snd_pcm_lib_preallocate_pages_for_all(pcm,
+				SNDRV_DMA_TYPE_DEV, NULL,
+				SIU_BUFFER_BYTES_MAX, SIU_BUFFER_BYTES_MAX);
+		if (ret < 0) {
+			dev_err(card->dev,
+			       "snd_pcm_lib_preallocate_pages_for_all() err=%d",
+				ret);
+			goto fail;
+		}
+
+		(*port_info)->pcm = pcm;
+
+		/* IO tasklets */
+		tasklet_init(&(*port_info)->playback.tasklet, siu_io_tasklet,
+			     (unsigned long)&(*port_info)->playback);
+		tasklet_init(&(*port_info)->capture.tasklet, siu_io_tasklet,
+			     (unsigned long)&(*port_info)->capture);
+	}
+
+	dev_info(card->dev, "SuperH SIU driver initialized.\n");
+	return 0;
+
+fail:
+	siu_free_port(siu_ports[pdev->id]);
+	dev_err(card->dev, "SIU: failed to initialize.\n");
+	return ret;
+}
+
+static void siu_pcm_free(struct snd_pcm *pcm)
+{
+	struct platform_device *pdev = to_platform_device(pcm->card->dev);
+	struct siu_port *port_info = siu_ports[pdev->id];
+
+	tasklet_kill(&port_info->capture.tasklet);
+	tasklet_kill(&port_info->playback.tasklet);
+
+	siu_free_port(port_info);
+	snd_pcm_lib_preallocate_free_for_all(pcm);
+
+	dev_dbg(pcm->card->dev, "%s\n", __func__);
+}
+
+static struct snd_pcm_ops siu_pcm_ops = {
+	.open		= siu_pcm_open,
+	.close		= siu_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= siu_pcm_hw_params,
+	.hw_free	= siu_pcm_hw_free,
+	.prepare	= siu_pcm_prepare,
+	.trigger	= siu_pcm_trigger,
+	.pointer	= siu_pcm_pointer_dma,
+};
+
+struct snd_soc_platform siu_platform = {
+	.name		= "siu-audio",
+	.pcm_ops 	= &siu_pcm_ops,
+	.pcm_new	= siu_pcm_new,
+	.pcm_free	= siu_pcm_free,
+};
+EXPORT_SYMBOL_GPL(siu_platform);