ASoC: rsnd: add common DMAEngine method
R-Car Sound driver will support DMA transfer in the future,
then, SSI/SRU/SRC will use it.
Current R-Car can't use soc-dmaengine-pcm.c since its DMAEngine
doesn't support dmaengine_prep_dma_cyclic(),
and SSI needs double plane transfer (which needs special submit) on DMAC.
This patch adds common DMAEngine method for it
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
index 420d6df..a357060 100644
--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -174,6 +174,138 @@
}
/*
+ * rsnd_dma functions
+ */
+static void rsnd_dma_continue(struct rsnd_dma *dma)
+{
+ /* push next A or B plane */
+ dma->submit_loop = 1;
+ schedule_work(&dma->work);
+}
+
+void rsnd_dma_start(struct rsnd_dma *dma)
+{
+ /* push both A and B plane*/
+ dma->submit_loop = 2;
+ schedule_work(&dma->work);
+}
+
+void rsnd_dma_stop(struct rsnd_dma *dma)
+{
+ dma->submit_loop = 0;
+ cancel_work_sync(&dma->work);
+ dmaengine_terminate_all(dma->chan);
+}
+
+static void rsnd_dma_complete(void *data)
+{
+ struct rsnd_dma *dma = (struct rsnd_dma *)data;
+ struct rsnd_priv *priv = dma->priv;
+ unsigned long flags;
+
+ rsnd_lock(priv, flags);
+
+ dma->complete(dma);
+
+ if (dma->submit_loop)
+ rsnd_dma_continue(dma);
+
+ rsnd_unlock(priv, flags);
+}
+
+static void rsnd_dma_do_work(struct work_struct *work)
+{
+ struct rsnd_dma *dma = container_of(work, struct rsnd_dma, work);
+ struct rsnd_priv *priv = dma->priv;
+ struct device *dev = rsnd_priv_to_dev(priv);
+ struct dma_async_tx_descriptor *desc;
+ dma_addr_t buf;
+ size_t len;
+ int i;
+
+ for (i = 0; i < dma->submit_loop; i++) {
+
+ if (dma->inquiry(dma, &buf, &len) < 0)
+ return;
+
+ desc = dmaengine_prep_slave_single(
+ dma->chan, buf, len, dma->dir,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc) {
+ dev_err(dev, "dmaengine_prep_slave_sg() fail\n");
+ return;
+ }
+
+ desc->callback = rsnd_dma_complete;
+ desc->callback_param = dma;
+
+ if (dmaengine_submit(desc) < 0) {
+ dev_err(dev, "dmaengine_submit() fail\n");
+ return;
+ }
+
+ }
+
+ dma_async_issue_pending(dma->chan);
+}
+
+int rsnd_dma_available(struct rsnd_dma *dma)
+{
+ return !!dma->chan;
+}
+
+static bool rsnd_dma_filter(struct dma_chan *chan, void *param)
+{
+ chan->private = param;
+
+ return true;
+}
+
+int rsnd_dma_init(struct rsnd_priv *priv, struct rsnd_dma *dma,
+ int is_play, int id,
+ int (*inquiry)(struct rsnd_dma *dma,
+ dma_addr_t *buf, int *len),
+ int (*complete)(struct rsnd_dma *dma))
+{
+ struct device *dev = rsnd_priv_to_dev(priv);
+ dma_cap_mask_t mask;
+
+ if (dma->chan) {
+ dev_err(dev, "it already has dma channel\n");
+ return -EIO;
+ }
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ dma->slave.shdma_slave.slave_id = id;
+
+ dma->chan = dma_request_channel(mask, rsnd_dma_filter,
+ &dma->slave.shdma_slave);
+ if (!dma->chan) {
+ dev_err(dev, "can't get dma channel\n");
+ return -EIO;
+ }
+
+ dma->dir = is_play ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+ dma->priv = priv;
+ dma->inquiry = inquiry;
+ dma->complete = complete;
+ INIT_WORK(&dma->work, rsnd_dma_do_work);
+
+ return 0;
+}
+
+void rsnd_dma_quit(struct rsnd_priv *priv,
+ struct rsnd_dma *dma)
+{
+ if (dma->chan)
+ dma_release_channel(dma->chan);
+
+ dma->chan = NULL;
+}
+
+/*
* rsnd_dai functions
*/
#define rsnd_dai_call(rdai, io, fn) \
