dw_spi: Fix missing final read in some polling situations
There is a possibility that the last word of a transaction will be lost
if data is not ready. Re-read in poll_transfer() to solve this issue
when poll_mode is enabled.
Verified on SPI touch screen device.
Signed-off-by: Major Lee <major_lee@wistron.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/spi/dw_spi.c b/drivers/spi/dw_spi.c
index 9043931..0838c79 100644
--- a/drivers/spi/dw_spi.c
+++ b/drivers/spi/dw_spi.c
@@ -413,6 +413,11 @@
{
while (dws->write(dws))
dws->read(dws);
+ /*
+ * There is a possibility that the last word of a transaction
+ * will be lost if data is not ready. Re-read to solve this issue.
+ */
+ dws->read(dws);
transfer_complete(dws);
}