This modifies the condition for using the software fallback
implementation for SPI_CS_WORD when the SPI controller is using a GPIO
for the CS line. When using a GPIO for CS, the hardware implementation
won't work, so we just enable the software fallback globally in this
case.
Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx>
---
drivers/spi/spi.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index e4fb87b304a0..03833924ca6c 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2841,11 +2841,13 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
return -EINVAL;
/* If an SPI controller does not support toggling the CS line on each
- * transfer (indicated by the SPI_CS_WORD flag), we can emulate it by
+ * transfer (indicated by the SPI_CS_WORD flag) or we are using a GPIO
+ * for the CS line, we can emulate the CS-per-word hardware function by
* splitting transfers into one-word transfers and ensuring that
* cs_change is set for each transfer.
*/
- if ((spi->mode & SPI_CS_WORD) && !(ctlr->mode_bits & SPI_CS_WORD)) {
+ if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits & SPI_CS_WORD) ||
+ gpio_is_valid(spi->cs_gpio))) {
size_t maxsize;
int ret;
--
2.17.1
