dmaengine: Save few bytes and increase readability of dma_request_chan()

Split IS_ERR_OR_NULL() check followed by additional conditional
to two simple conditionals. This increases readability and saves memory:

Function                                     old     new   delta
dma_request_chan                             700     697      -3
Total: Before=10224, After=10221, chg -0.03%

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200828144519.14483-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index ac8ef6cf762672c5cc56a99acd5ce57f28952b09..7974fa0400d8c2ab3fecfacabc86fbb4353334f8 100644 (file)
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -847,8 +847,10 @@ struct dma_chan *dma_request_chan(struct device *dev, const char *name)
        }
        mutex_unlock(&dma_list_mutex);
 
-       if (IS_ERR_OR_NULL(chan))
-               return chan ? chan : ERR_PTR(-EPROBE_DEFER);
+       if (IS_ERR(chan))
+               return chan;
+       if (!chan)
+               return ERR_PTR(-EPROBE_DEFER);
 
 found:
 #ifdef CONFIG_DEBUG_FS