1 files changed, 28 insertions, 11 deletions

diff --git a/drivers/dma/shdma.c b/drivers/dma/shdma.c
index ed3ef22e68a4..c2b0172a7589 100644
--- a/drivers/dma/shdma.c
+++ b/drivers/dma/shdma.c
@@ -189,7 +189,7 @@ 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;
 
@@ -265,7 +265,7 @@ 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;
@@ -289,6 +289,7 @@ static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
         struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
         struct sh_desc *desc;
         struct sh_dmae_slave *param = chan->private;
+        int ret;
 
         pm_runtime_get_sync(sh_chan->dev);
 
@@ -297,14 +298,18 @@ 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)
-                        return -EINVAL;
+                if (!cfg) {
+                        ret = -EINVAL;
+                        goto efindslave;
+                }
 
-                if (test_and_set_bit(param->slave_id, sh_dmae_slave_used))
-                        return -EBUSY;
+                if (test_and_set_bit(param->slave_id, sh_dmae_slave_used)) {
+                        ret = -EBUSY;
+                        goto etestused;
+                }
 
                 param->config = cfg;
 
@@ -333,10 +338,20 @@ static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
         }
         spin_unlock_bh(&sh_chan->desc_lock);
 
-        if (!sh_chan->descs_allocated)
-                pm_runtime_put(sh_chan->dev);
+        if (!sh_chan->descs_allocated) {
+                ret = -ENOMEM;
+                goto edescalloc;
+        }
 
         return sh_chan->descs_allocated;
+
+edescalloc:
+        if (param)
+                clear_bit(param->slave_id, sh_dmae_slave_used);
+etestused:
+efindslave:
+        pm_runtime_put(sh_chan->dev);
+        return ret;
 }
 
 /*
@@ -558,12 +573,14 @@ 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) {
@@ -576,7 +593,7 @@ 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);
 }
 
@@ -857,7 +874,7 @@ 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;