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| author | sxauwsk <sxauwsk@163.com> | 2018-04-16 23:01:27 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-06-20 22:02:43 +0300 |
| commit | c5b6316c3f5139cbc1d9a37cd6b86bb7be3802bf (patch) | |
| tree | c7c56e5ecab80e31078c8bd57289bf0403bfd809 /drivers/spi | |
| parent | 5f4bf078e779927200b246d05f569dbe75543ace (diff) | |
| download | linux-c5b6316c3f5139cbc1d9a37cd6b86bb7be3802bf.tar.xz | |
spi: cadence: Add usleep_range() for cdns_spi_fill_tx_fifo()
[ Upstream commit 49530e6411789c1b9ea3ebc58e520c19d1c3752f ]
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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-cadence.c | 8 |
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 |