From: Patrice Chotard patrice.chotard@foss.st.com
[ Upstream commit d38fa9a155b2829b7e2cfcf8a4171b6dd3672808 ]
In U-boot side, an issue has been encountered when QSPI source clock is running at low frequency (24 MHz for example), waiting for TCF bit to be set didn't ensure that all data has been send out the FIFO, we should also wait that BUSY bit is cleared.
To prevent similar issue in kernel driver, we implement similar behavior by always waiting BUSY bit to be cleared.
Signed-off-by: Patrice Chotard patrice.chotard@foss.st.com Link: https://lore.kernel.org/r/20210603073421.8441-1-patrice.chotard@foss.st.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-stm32-qspi.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c index 4e726929bb4f..ea77d915216a 100644 --- a/drivers/spi/spi-stm32-qspi.c +++ b/drivers/spi/spi-stm32-qspi.c @@ -291,7 +291,7 @@ static int stm32_qspi_wait_cmd(struct stm32_qspi *qspi, int err = 0;
if (!op->data.nbytes) - return stm32_qspi_wait_nobusy(qspi); + goto wait_nobusy;
if (readl_relaxed(qspi->io_base + QSPI_SR) & SR_TCF) goto out; @@ -312,6 +312,9 @@ static int stm32_qspi_wait_cmd(struct stm32_qspi *qspi, out: /* clear flags */ writel_relaxed(FCR_CTCF | FCR_CTEF, qspi->io_base + QSPI_FCR); +wait_nobusy: + if (!err) + err = stm32_qspi_wait_nobusy(qspi);
return err; }