diff mbox series

[v7,10/14] spi: mxic: Fix the transmit path

Message ID 20211217161654.367782-11-miquel.raynal@bootlin.com (mailing list archive)
State Superseded
Headers show
Series External ECC engines & Macronix support | expand

Commit Message

Miquel Raynal Dec. 17, 2021, 4:16 p.m. UTC 
By working with external hardware ECC engines, we figured out that
Under certain circumstances, it is needed for the SPI controller to
check INT_TX_EMPTY and INT_RX_NOT_EMPTY in both receive and transmit
path (not only in the receive path). The delay penalty being
negligible, move this code in the common path.

Fixes: b942d80b0a39 ("spi: Add MXIC controller driver")
Cc: stable@vger.kernel.org
Suggested-by: Mason Yang <masonccyang@mxic.com.tw>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Zhengxun Li <zhengxunli@mxic.com.tw>
Reviewed-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/spi-mxic.c | 28 ++++++++++++----------------
 1 file changed, 12 insertions(+), 16 deletions(-)
diff mbox series

Patch

diff --git a/drivers/spi/spi-mxic.c b/drivers/spi/spi-mxic.c
index 67d05ee8d6a0..aedc9a144b82 100644
--- a/drivers/spi/spi-mxic.c
+++ b/drivers/spi/spi-mxic.c
@@ -304,25 +304,21 @@  static int mxic_spi_data_xfer(struct mxic_spi *mxic, const void *txbuf,
 
 		writel(data, mxic->regs + TXD(nbytes % 4));
 
+		ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
+					 sts & INT_TX_EMPTY, 0, USEC_PER_SEC);
+		if (ret)
+			return ret;
+
+		ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
+					 sts & INT_RX_NOT_EMPTY, 0,
+					 USEC_PER_SEC);
+		if (ret)
+			return ret;
+
+		data = readl(mxic->regs + RXD);
 		if (rxbuf) {
-			ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
-						 sts & INT_TX_EMPTY, 0,
-						 USEC_PER_SEC);
-			if (ret)
-				return ret;
-
-			ret = readl_poll_timeout(mxic->regs + INT_STS, sts,
-						 sts & INT_RX_NOT_EMPTY, 0,
-						 USEC_PER_SEC);
-			if (ret)
-				return ret;
-
-			data = readl(mxic->regs + RXD);
 			data >>= (8 * (4 - nbytes));
 			memcpy(rxbuf + pos, &data, nbytes);
-			WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY);
-		} else {
-			readl(mxic->regs + RXD);
 		}
 		WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY);