[PATCH v8 10/14] spi: mxic: Fix the transmit path
From: Miquel Raynal <miquel.raynal@bootlin.com>
Date: 2021-12-21 17:49:05
Also in:
linux-spi
Subsystem:
spi subsystem, the rest · Maintainers:
Mark Brown, Linus Torvalds
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 <redacted>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Zhengxun Li <redacted>
Reviewed-by: Mark Brown <broonie@kernel.org>
---
drivers/spi/spi-mxic.c | 28 ++++++++++++----------------
1 file changed, 12 insertions(+), 16 deletions(-)
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);
--
2.27.0