[PATCH 5.17 080/298] spi: fsi: Fix spurious timeout

From: Greg Kroah-Hartman
Date: Mon Jun 13 2022 - 10:22:11 EST


From: Eddie James <eajames@xxxxxxxxxxxxx>

[ Upstream commit 61bf40ef51aa73f6216b33563271b6acf7ea8d70 ]

The driver may return a timeout error even if the status register
indicates that the transfer may proceed. Fix this by restructuring
the polling loop.

Fixes: 89b35e3f2851 ("spi: fsi: Implement a timeout for polling status")
Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220525165852.33167-2-eajames@xxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/spi/spi-fsi.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/spi/spi-fsi.c b/drivers/spi/spi-fsi.c
index d403a7a3021d..72ab066ce552 100644
--- a/drivers/spi/spi-fsi.c
+++ b/drivers/spi/spi-fsi.c
@@ -319,12 +319,12 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,

end = jiffies + msecs_to_jiffies(SPI_FSI_STATUS_TIMEOUT_MS);
do {
+ if (time_after(jiffies, end))
+ return -ETIMEDOUT;
+
rc = fsi_spi_status(ctx, &status, "TX");
if (rc)
return rc;
-
- if (time_after(jiffies, end))
- return -ETIMEDOUT;
} while (status & SPI_FSI_STATUS_TDR_FULL);

sent += nb;
@@ -337,12 +337,12 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
while (transfer->len > recv) {
end = jiffies + msecs_to_jiffies(SPI_FSI_STATUS_TIMEOUT_MS);
do {
+ if (time_after(jiffies, end))
+ return -ETIMEDOUT;
+
rc = fsi_spi_status(ctx, &status, "RX");
if (rc)
return rc;
-
- if (time_after(jiffies, end))
- return -ETIMEDOUT;
} while (!(status & SPI_FSI_STATUS_RDR_FULL));

rc = fsi_spi_read_reg(ctx, SPI_FSI_DATA_RX, &in);
--
2.35.1