SH: constify multiple DMA related objects and references to them

Lists of DMA channels and slaves are not changed, make them constant. Besides,
SH7724 channel and slave configuration of both DMA controllers is identical,
remove the extra copy of the configuration data.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/dma/shdma.c b/drivers/dma/shdma.c
index 7a18b58..aab352a 100644
--- a/drivers/dma/shdma.c
+++ b/drivers/dma/shdma.c
@@ -188,7 +188,7 @@ static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
 	struct sh_dmae_device *shdev = container_of(sh_chan->common.device,
 						struct sh_dmae_device, common);
 	struct sh_dmae_pdata *pdata = shdev->pdata;
-	struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->id];
+	const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->id];
 	u16 __iomem *addr = shdev->dmars + chan_pdata->dmars / sizeof(u16);
 	int shift = chan_pdata->dmars_bit;
 
@@ -264,7 +264,7 @@ static struct sh_desc *sh_dmae_get_desc(struct sh_dmae_chan *sh_chan)
 	return NULL;
 }
 
-static struct sh_dmae_slave_config *sh_dmae_find_slave(
+static const struct sh_dmae_slave_config *sh_dmae_find_slave(
 	struct sh_dmae_chan *sh_chan, struct sh_dmae_slave *param)
 {
 	struct dma_device *dma_dev = sh_chan->common.device;
@@ -296,7 +296,7 @@ static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
 	 * never runs concurrently with itself or free_chan_resources.
 	 */
 	if (param) {
-		struct sh_dmae_slave_config *cfg;
+		const struct sh_dmae_slave_config *cfg;
 
 		cfg = sh_dmae_find_slave(sh_chan, param);
 		if (!cfg)
@@ -557,12 +557,14 @@ static struct dma_async_tx_descriptor *sh_dmae_prep_slave_sg(
 {
 	struct sh_dmae_slave *param;
 	struct sh_dmae_chan *sh_chan;
+	dma_addr_t slave_addr;
 
 	if (!chan)
 		return NULL;
 
 	sh_chan = to_sh_chan(chan);
 	param = chan->private;
+	slave_addr = param->config->addr;
 
 	/* Someone calling slave DMA on a public channel? */
 	if (!param || !sg_len) {
@@ -575,7 +577,7 @@ static struct dma_async_tx_descriptor *sh_dmae_prep_slave_sg(
 	 * if (param != NULL), this is a successfully requested slave channel,
 	 * therefore param->config != NULL too.
 	 */
-	return sh_dmae_prep_sg(sh_chan, sgl, sg_len, &param->config->addr,
+	return sh_dmae_prep_sg(sh_chan, sgl, sg_len, &slave_addr,
 			       direction, flags);
 }
 
@@ -856,7 +858,7 @@ static int __devinit sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
 					int irq, unsigned long flags)
 {
 	int err;
-	struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
+	const struct sh_dmae_channel *chan_pdata = &shdev->pdata->channel[id];
 	struct platform_device *pdev = to_platform_device(shdev->common.dev);
 	struct sh_dmae_chan *new_sh_chan;