[PATCH/RFC 5/6] mmc: sh_mmcif: add support for Device Tree DMA bindings

From: Guennadi Liakhovetski
Date: Wed Apr 10 2013 - 18:21:11 EST


To use DMA in the Device Tree case the driver has to be modified
to use suitable API to obtain DMA channels.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@xxxxxxxxx>
---
drivers/mmc/host/sh_mmcif.c | 29 ++++++++++++++++++-----------
1 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index ba76a53..446d948 100644
--- a/drivers/mmc/host/sh_mmcif.c
+++ b/drivers/mmc/host/sh_mmcif.c
@@ -386,25 +386,30 @@ static void sh_mmcif_request_dma(struct sh_mmcif_host *host,

host->dma_active = false;

- if (!pdata)
- return;
-
- if (pdata->slave_id_tx <= 0 || pdata->slave_id_rx <= 0)
- return;
+ if (pdata) {
+ if (pdata->slave_id_tx <= 0 || pdata->slave_id_rx <= 0)
+ return;
+ } else {
+ if (!host->pd->dev.of_node)
+ return;
+ }

/* We can only either use DMA for both Tx and Rx or not use it at all */
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);

- host->chan_tx = dma_request_channel(mask, shdma_chan_filter,
- (void *)pdata->slave_id_tx);
+ host->chan_tx = dma_request_slave_channel_compat(mask, shdma_chan_filter,
+ pdata ? (void *)pdata->slave_id_tx : NULL,
+ &host->pd->dev, "tx");
dev_dbg(&host->pd->dev, "%s: TX: got channel %p\n", __func__,
host->chan_tx);

if (!host->chan_tx)
return;

- cfg.slave_id = pdata->slave_id_tx;
+ /* In the OF case the driver will get the slave ID from the DT */
+ if (pdata)
+ cfg.slave_id = pdata->slave_id_tx;
cfg.direction = DMA_MEM_TO_DEV;
cfg.dst_addr = res->start + MMCIF_CE_DATA;
cfg.src_addr = 0;
@@ -412,15 +417,17 @@ static void sh_mmcif_request_dma(struct sh_mmcif_host *host,
if (ret < 0)
goto ecfgtx;

- host->chan_rx = dma_request_channel(mask, shdma_chan_filter,
- (void *)pdata->slave_id_rx);
+ host->chan_rx = dma_request_slave_channel_compat(mask, shdma_chan_filter,
+ pdata ? (void *)pdata->slave_id_rx : NULL,
+ &host->pd->dev, "rx");
dev_dbg(&host->pd->dev, "%s: RX: got channel %p\n", __func__,
host->chan_rx);

if (!host->chan_rx)
goto erqrx;

- cfg.slave_id = pdata->slave_id_rx;
+ if (pdata)
+ cfg.slave_id = pdata->slave_id_rx;
cfg.direction = DMA_DEV_TO_MEM;
cfg.dst_addr = 0;
cfg.src_addr = res->start + MMCIF_CE_DATA;
--
1.7.2.5

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