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authorsxauwsk <sxauwsk@163.com>2018-04-16 22:01:27 +0200
committerMark Brown <broonie@kernel.org>2018-04-18 12:28:29 +0200
commit49530e6411789c1b9ea3ebc58e520c19d1c3752f (patch)
treee9a684422ec5ae49ad5a6fe20e71a11bf68c0888
parentspi: sh-msiof: Fix bit field overflow writes to TSCR/RSCR (diff)
downloadlinux-49530e6411789c1b9ea3ebc58e520c19d1c3752f.tar.xz
linux-49530e6411789c1b9ea3ebc58e520c19d1c3752f.zip
spi: cadence: Add usleep_range() for cdns_spi_fill_tx_fifo()
In case of xspi work in busy condition, may send bytes failed. once something wrong, spi controller did't work any more My test found this situation appear in both of read/write process. so when TX FIFO is full, add one byte delay before send data; Signed-off-by: sxauwsk <sxauwsk@163.com> Signed-off-by: Mark Brown <broonie@kernel.org>
-rw-r--r--drivers/spi/spi-cadence.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c
index 5c9516ae4942..4a001634023e 100644
--- a/drivers/spi/spi-cadence.c
+++ b/drivers/spi/spi-cadence.c
@@ -313,6 +313,14 @@ static void cdns_spi_fill_tx_fifo(struct cdns_spi *xspi)
while ((trans_cnt < CDNS_SPI_FIFO_DEPTH) &&
(xspi->tx_bytes > 0)) {
+
+ /* When xspi in busy condition, bytes may send failed,
+ * then spi control did't work thoroughly, add one byte delay
+ */
+ if (cdns_spi_read(xspi, CDNS_SPI_ISR) &
+ CDNS_SPI_IXR_TXFULL)
+ usleep_range(10, 20);
+
if (xspi->txbuf)
cdns_spi_write(xspi, CDNS_SPI_TXD, *xspi->txbuf++);
else