[PATCHv2 1/2] dw_dmac: store direction in the custom channel structure

[PATCHv2 1/2] dw_dmac: store direction in the custom channel structure

[Andy Shevchenko]

Currently the direction value comes from the generic slave configuration
structure and explicitly as a preparation function parameter. The first one is
kinda obsoleted. Thus, we have to store the value passed to the preparation
function somewhere in our structures to be able to use it later. The best
candidate to provide the storage is a custom channel structure. Until now we
still keep and check the direction field of the slave config structure as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/dma/dw_dmac.c      |   12 ++++++++++--
 drivers/dma/dw_dmac_regs.h |   14 ++++++++------
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index 5e2c4dc..1100fa0 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -178,9 +178,9 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
 		cfghi = dws->cfg_hi;
 		cfglo |= dws->cfg_lo & ~DWC_CFGL_CH_PRIOR_MASK;
 	} else {
-		if (dwc->dma_sconfig.direction == DMA_MEM_TO_DEV)
+		if (dwc->direction == DMA_MEM_TO_DEV)
 			cfghi = DWC_CFGH_DST_PER(dwc->dma_sconfig.slave_id);
-		else if (dwc->dma_sconfig.direction == DMA_DEV_TO_MEM)
+		else if (dwc->direction == DMA_DEV_TO_MEM)
 			cfghi = DWC_CFGH_SRC_PER(dwc->dma_sconfig.slave_id);
 	}
 
@@ -723,6 +723,8 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
 		return NULL;
 	}
 
+	dwc->direction = DMA_MEM_TO_MEM;
+
 	data_width = min_t(unsigned int, dwc->dw->data_width[dwc_get_sms(dws)],
 					 dwc->dw->data_width[dwc_get_dms(dws)]);
 
@@ -807,6 +809,8 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 	if (unlikely(!dws || !sg_len))
 		return NULL;
 
+	dwc->direction = direction;
+
 	prev = first = NULL;
 
 	switch (direction) {
@@ -983,6 +987,7 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 		return -EINVAL;
 
 	memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
+	dwc->direction = sconfig->direction;
 
 	convert_burst(&dwc->dma_sconfig.src_maxburst);
 	convert_burst(&dwc->dma_sconfig.dst_maxburst);
@@ -1339,6 +1344,8 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
 	if (unlikely(!is_slave_xfer(direction)))
 		goto out_err;
 
+	dwc->direction = direction;
+
 	if (direction == DMA_MEM_TO_DEV)
 		reg_width = __ffs(sconfig->dst_addr_width);
 	else
@@ -1713,6 +1720,7 @@ static int __devinit dw_probe(struct platform_device *pdev)
 		channel_clear_bit(dw, CH_EN, dwc->mask);
 
 		dwc->dw = dw;
+		dwc->direction = DMA_TRANS_NONE;
 
 		/* hardware configuration */
 		if (autocfg) {
diff --git a/drivers/dma/dw_dmac_regs.h b/drivers/dma/dw_dmac_regs.h
index 8881e9b..f9532c2 100644
--- a/drivers/dma/dw_dmac_regs.h
+++ b/drivers/dma/dw_dmac_regs.h
@@ -9,6 +9,7 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/dmaengine.h>
 #include <linux/dw_dmac.h>
 
 #define DW_DMA_MAX_NR_CHANNELS	8
@@ -184,12 +185,13 @@ enum dw_dmac_flags {
 };
 
 struct dw_dma_chan {
-	struct dma_chan		chan;
-	void __iomem		*ch_regs;
-	u8			mask;
-	u8			priority;
-	bool			paused;
-	bool			initialized;
+	struct dma_chan			chan;
+	void __iomem			*ch_regs;
+	u8				mask;
+	u8				priority;
+	enum dma_transfer_direction	direction;
+	bool				paused;
+	bool				initialized;
 
 	/* software emulation of the LLP transfers */
 	struct list_head	*tx_list;
-- 
1.7.10.4

[PATCHv2 2/2] dw_dmac: make usage of dw_dma_slave optional

[Andy Shevchenko]

The driver requires a custom slave configuration to be present to be able to
make the slave transfers. Nevertheless, in some cases we need only the request
line as an additional information to the generic slave configuration.  The
request line is provided by slave_id parameter of the dma_slave_config
structure. That's why the custom slave configuration could be optional for such
cases.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/dma/dw_dmac.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index 1100fa0..6e20746 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -50,11 +50,12 @@ static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave)
 		struct dw_dma_slave *__slave = (_chan->private);	\
 		struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan);	\
 		struct dma_slave_config	*_sconfig = &_dwc->dma_sconfig;	\
+		bool _is_slave = is_slave_xfer(_dwc->direction);	\
 		int _dms = dwc_get_dms(__slave);		\
 		int _sms = dwc_get_sms(__slave);		\
-		u8 _smsize = __slave ? _sconfig->src_maxburst :	\
+		u8 _smsize = _is_slave ? _sconfig->src_maxburst :	\
 			DW_DMA_MSIZE_16;			\
-		u8 _dmsize = __slave ? _sconfig->dst_maxburst :	\
+		u8 _dmsize = _is_slave ? _sconfig->dst_maxburst :	\
 			DW_DMA_MSIZE_16;			\
 								\
 		(DWC_CTLL_DST_MSIZE(_dmsize)			\
@@ -325,7 +326,7 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
 	list_splice_init(&desc->tx_list, &dwc->free_list);
 	list_move(&desc->desc_node, &dwc->free_list);
 
-	if (!dwc->chan.private) {
+	if (!is_slave_xfer(dwc->direction)) {
 		struct device *parent = chan2parent(&dwc->chan);
 		if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
 			if (txd->flags & DMA_COMPL_DEST_UNMAP_SINGLE)
@@ -806,7 +807,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 
 	dev_vdbg(chan2dev(chan), "%s\n", __func__);
 
-	if (unlikely(!dws || !sg_len))
+	if (unlikely(!is_slave_xfer(direction) || !sg_len))
 		return NULL;
 
 	dwc->direction = direction;
@@ -982,8 +983,8 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 {
 	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
 
-	/* Check if it is chan is configured for slave transfers */
-	if (!chan->private)
+	/* Check if chan will be configured for slave transfers */
+	if (!is_slave_xfer(sconfig->direction))
 		return -EINVAL;
 
 	memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
-- 
1.7.10.4

Re: [PATCHv2 1/2] dw_dmac: store direction in the custom channel structure

[Viresh Kumar]

On 21 November 2012 14:12, Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
> Currently the direction value comes from the generic slave configuration
> structure and explicitly as a preparation function parameter. The first one is
> kinda obsoleted. Thus, we have to store the value passed to the preparation
> function somewhere in our structures to be able to use it later. The best
> candidate to provide the storage is a custom channel structure. Until now we
> still keep and check the direction field of the slave config structure as well.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

Vinod, these patches look fine to me. Please apply them for 3.8.