fix conv depthwise bug (#27278)

Fix conv deepwise bug when in_channels=1.

python/paddle/nn/functional/conv.py

@@ -267,8 +267,8 @@ def conv1d(x,
     dilation = utils.convert_to_list(dilation, 1, 'dilation') + [1]
 
     l_type = "conv2d"
-    if (num_channels == groups and num_filters % num_channels == 0 and
-            not use_cudnn):
+    if (num_channels == groups and num_channels != 1 and
+            num_filters % num_channels == 0 and not use_cudnn):
         l_type = 'depthwise_conv2d'
         use_cudnn = False
 
@@ -491,7 +491,8 @@ def conv2d(x,
     dilation = utils.convert_to_list(dilation, 2, 'dilation')
 
     l_type = "conv2d"
-    if (num_channels == groups and num_filters % num_channels == 0):
+    if (num_channels == groups and num_channels != 1 and
+            num_filters % num_channels == 0):
         l_type = 'depthwise_conv2d'
         use_cudnn = False
 
@@ -761,7 +762,8 @@ def conv_transpose1d(x,
 
     op_type = 'conv2d_transpose'
     num_filters = weight.shape[1]
-    if (num_channels == groups and num_filters == 1 and not use_cudnn):
+    if (num_channels == groups and num_channels != 1 and num_filters == 1 and
+            not use_cudnn):
         op_type = 'depthwise_conv2d_transpose'
         use_cudnn = False
 
@@ -1010,7 +1012,7 @@ def conv_transpose2d(x,
 
     op_type = 'conv2d_transpose'
     num_filters = weight.shape[1]
-    if (num_channels == groups and num_filters == 1):
+    if (num_channels == groups and num_channels != 1 and num_filters == 1):
         op_type = 'depthwise_conv2d_transpose'
         use_cudnn = False