spi: sirf: set SPI controller in RISC IO chipselect mode
SPI bitbang supply "chipselect" interface for change chip-select line
, in the SiRFSoC SPI controller, we need to enable "SPI_CS_IO_MODE",
otherwise, spi_sirfsoc_chipselect() has no effect.
now the driver is working is because SPI controller will control CS
automatically without SPI_CS_IO_MODE. this patch makes the CS controller
really controlled by software.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/spi/spi-sirf.c b/drivers/spi/spi-sirf.c
index 51d7c98..9b30743 100644
--- a/drivers/spi/spi-sirf.c
+++ b/drivers/spi/spi-sirf.c
@@ -559,6 +559,11 @@
regval &= ~SIRFSOC_SPI_CMD_MODE;
sspi->tx_by_cmd = false;
}
+ /*
+ * set spi controller in RISC chipselect mode, we are controlling CS by
+ * software BITBANG_CS_ACTIVE and BITBANG_CS_INACTIVE.
+ */
+ regval |= SIRFSOC_SPI_CS_IO_MODE;
writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
if (IS_DMA_VALID(t)) {