[PATCH V03 2/5] dmaengine: core: Move and merge the code paths using private_candidate

[Peter Ujfalusi]

Channel matching with private_candidate() is used in two paths, the error
checking is slightly different in them and they are duplicating code also.
Move the code under find_candidate() to provide consistent execution and
going to allow us to reuse this mode of channel lookup later.

Signed-off-by: Peter Ujfalusi 
Reviewed-by: Andy Shevchenko 
Reviewed-by: Arnd Bergmann 
---
 drivers/dma/dmaengine.c | 81 +
 1 file changed, 42 insertions(+), 39 deletions(-)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 6311e1fc80be..ea9d66982d40 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -546,6 +546,42 @@ static struct dma_chan *private_candidate(const 
dma_cap_mask_t *mask,
return NULL;
 }
 
+static struct dma_chan *find_candidate(struct dma_device *device,
+  const dma_cap_mask_t *mask,
+  dma_filter_fn fn, void *fn_param)
+{
+   struct dma_chan *chan = private_candidate(mask, device, fn, fn_param);
+   int err;
+
+   if (chan) {
+   /* Found a suitable channel, try to grab, prep, and return it.
+* We first set DMA_PRIVATE to disable balance_ref_count as this
+* channel will not be published in the general-purpose
+* allocator
+*/
+   dma_cap_set(DMA_PRIVATE, device->cap_mask);
+   device->privatecnt++;
+   err = dma_chan_get(chan);
+
+   if (err) {
+   if (err == -ENODEV) {
+   pr_debug("%s: %s module removed\n", __func__,
+dma_chan_name(chan));
+   list_del_rcu(>global_node);
+   } else
+   pr_debug("%s: failed to get %s: (%d)\n",
+__func__, dma_chan_name(chan), err);
+
+   if (--device->privatecnt == 0)
+   dma_cap_clear(DMA_PRIVATE, device->cap_mask);
+
+   chan = ERR_PTR(err);
+   }
+   }
+
+   return chan ? chan : ERR_PTR(-EPROBE_DEFER);
+}
+
 /**
  * dma_get_slave_channel - try to get specific channel exclusively
  * @chan: target channel
@@ -584,7 +620,6 @@ struct dma_chan *dma_get_any_slave_channel(struct 
dma_device *device)
 {
dma_cap_mask_t mask;
struct dma_chan *chan;
-   int err;
 
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
@@ -592,23 +627,11 @@ struct dma_chan *dma_get_any_slave_channel(struct 
dma_device *device)
/* lock against __dma_request_channel */
mutex_lock(_list_mutex);
 
-   chan = private_candidate(, device, NULL, NULL);
-   if (chan) {
-   dma_cap_set(DMA_PRIVATE, device->cap_mask);
-   device->privatecnt++;
-   err = dma_chan_get(chan);
-   if (err) {
-   pr_debug("%s: failed to get %s: (%d)\n",
-   __func__, dma_chan_name(chan), err);
-   chan = NULL;
-   if (--device->privatecnt == 0)
-   dma_cap_clear(DMA_PRIVATE, device->cap_mask);
-   }
-   }
+   chan = find_candidate(device, , NULL, NULL);
 
mutex_unlock(_list_mutex);
 
-   return chan;
+   return IS_ERR(chan) ? NULL : chan;
 }
 EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
 
@@ -625,35 +648,15 @@ struct dma_chan *__dma_request_channel(const 
dma_cap_mask_t *mask,
 {
struct dma_device *device, *_d;
struct dma_chan *chan = NULL;
-   int err;
 
/* Find a channel */
mutex_lock(_list_mutex);
list_for_each_entry_safe(device, _d, _device_list, global_node) {
-   chan = private_candidate(mask, device, fn, fn_param);
-   if (chan) {
-   /* Found a suitable channel, try to grab, prep, and
-* return it.  We first set DMA_PRIVATE to disable
-* balance_ref_count as this channel will not be
-* published in the general-purpose allocator
-*/
-   dma_cap_set(DMA_PRIVATE, device->cap_mask);
-   device->privatecnt++;
-   err = dma_chan_get(chan);
+   chan = find_candidate(device, mask, fn, fn_param);
+   if (!IS_ERR(chan))
+   break;
 
-   if (err == -ENODEV) {
-   pr_debug("%s: %s module removed\n",
-__func__, dma_chan_name(chan));
-   list_del_rcu(>global_node);
-   } else if (err)
-   pr_debug("%s: failed to get %s: (%d)\n",
-   

[PATCH V03 2/5] dmaengine: core: Move and merge the code paths using private_candidate

[Peter Ujfalusi]

Channel matching with private_candidate() is used in two paths, the error
checking is slightly different in them and they are duplicating code also.
Move the code under find_candidate() to provide consistent execution and
going to allow us to reuse this mode of channel lookup later.

Signed-off-by: Peter Ujfalusi 
Reviewed-by: Andy Shevchenko 
Reviewed-by: Arnd Bergmann 
---
 drivers/dma/dmaengine.c | 81 +
 1 file changed, 42 insertions(+), 39 deletions(-)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 6311e1fc80be..ea9d66982d40 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -546,6 +546,42 @@ static struct dma_chan *private_candidate(const 
dma_cap_mask_t *mask,
return NULL;
 }
 
+static struct dma_chan *find_candidate(struct dma_device *device,
+  const dma_cap_mask_t *mask,
+  dma_filter_fn fn, void *fn_param)
+{
+   struct dma_chan *chan = private_candidate(mask, device, fn, fn_param);
+   int err;
+
+   if (chan) {
+   /* Found a suitable channel, try to grab, prep, and return it.
+* We first set DMA_PRIVATE to disable balance_ref_count as this
+* channel will not be published in the general-purpose
+* allocator
+*/
+   dma_cap_set(DMA_PRIVATE, device->cap_mask);
+   device->privatecnt++;
+   err = dma_chan_get(chan);
+
+   if (err) {
+   if (err == -ENODEV) {
+   pr_debug("%s: %s module removed\n", __func__,
+dma_chan_name(chan));
+   list_del_rcu(>global_node);
+   } else
+   pr_debug("%s: failed to get %s: (%d)\n",
+__func__, dma_chan_name(chan), err);
+
+   if (--device->privatecnt == 0)
+   dma_cap_clear(DMA_PRIVATE, device->cap_mask);
+
+   chan = ERR_PTR(err);
+   }
+   }
+
+   return chan ? chan : ERR_PTR(-EPROBE_DEFER);
+}
+
 /**
  * dma_get_slave_channel - try to get specific channel exclusively
  * @chan: target channel
@@ -584,7 +620,6 @@ struct dma_chan *dma_get_any_slave_channel(struct 
dma_device *device)
 {
dma_cap_mask_t mask;
struct dma_chan *chan;
-   int err;
 
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
@@ -592,23 +627,11 @@ struct dma_chan *dma_get_any_slave_channel(struct 
dma_device *device)
/* lock against __dma_request_channel */
mutex_lock(_list_mutex);
 
-   chan = private_candidate(, device, NULL, NULL);
-   if (chan) {
-   dma_cap_set(DMA_PRIVATE, device->cap_mask);
-   device->privatecnt++;
-   err = dma_chan_get(chan);
-   if (err) {
-   pr_debug("%s: failed to get %s: (%d)\n",
-   __func__, dma_chan_name(chan), err);
-   chan = NULL;
-   if (--device->privatecnt == 0)
-   dma_cap_clear(DMA_PRIVATE, device->cap_mask);
-   }
-   }
+   chan = find_candidate(device, , NULL, NULL);
 
mutex_unlock(_list_mutex);
 
-   return chan;
+   return IS_ERR(chan) ? NULL : chan;
 }
 EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
 
@@ -625,35 +648,15 @@ struct dma_chan *__dma_request_channel(const 
dma_cap_mask_t *mask,
 {
struct dma_device *device, *_d;
struct dma_chan *chan = NULL;
-   int err;
 
/* Find a channel */
mutex_lock(_list_mutex);
list_for_each_entry_safe(device, _d, _device_list, global_node) {
-   chan = private_candidate(mask, device, fn, fn_param);
-   if (chan) {
-   /* Found a suitable channel, try to grab, prep, and
-* return it.  We first set DMA_PRIVATE to disable
-* balance_ref_count as this channel will not be
-* published in the general-purpose allocator
-*/
-   dma_cap_set(DMA_PRIVATE, device->cap_mask);
-   device->privatecnt++;
-   err = dma_chan_get(chan);
+   chan = find_candidate(device, mask, fn, fn_param);
+   if (!IS_ERR(chan))
+   break;
 
-   if (err == -ENODEV) {
-   pr_debug("%s: %s module removed\n",
-__func__, dma_chan_name(chan));
-   list_del_rcu(>global_node);
-   } else if (err)
-