[DeviceDrivers] fix the compiling warning.
@@ -360,7 +360,11 @@ rt_size_t rt_pipe_read (rt_device_t device, rt_off_t pos, void *buffer, rt_siz
int read_bytes = 0;
rt_pipe_t *pipe = (rt_pipe_t *)device;
- if (device == RT_NULL) return -EINVAL;
+ if (device == RT_NULL)
+ {
+ rt_set_errno(-EINVAL);
+ return 0;
+ }
if (count == 0) return 0;
pbuf = (uint8_t*)buffer;
@@ -384,7 +388,11 @@ rt_size_t rt_pipe_write (rt_device_t device, rt_off_t pos, const void *buffer,
int write_bytes = 0;
rt_pipe_t *pipe = (rt_pipe_t *)device;
- if (device == RT_NULL) return -EINVAL;
+ if (device == RT_NULL)
+ {
+ rt_set_errno(-EINVAL);
+ return 0;
+ }
if (count == 0) return 0;
pbuf = (uint8_t*)buffer;
