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 <[email protected]> Signed-off-by: Alan Cox <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
josf · Dec 15, 2010 · 3d0b608 · 3d0b608
1 parent 54efdfe
commit 3d0b608
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/drivers/spi/dw_spi.c b/drivers/spi/dw_spi.c
@@ -413,6 +413,11 @@ static void poll_transfer(struct dw_spi *dws)
 {
 	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);
 }