The patch spi: always use software fallback for SPI_CS_WORD when using cs_gio has been applied to the spi tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From 71388b21569754ecd36eabd66fd9ca8c6d761fed Mon Sep 17 00:00:00 2001 From: David Lechner <david@xxxxxxxxxxxxxx> Date: Tue, 18 Sep 2018 12:08:48 -0500 Subject: [PATCH] spi: always use software fallback for SPI_CS_WORD when using cs_gio 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> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- 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 be73d236919f..a358acdd98d3 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2832,11 +2832,13 @@ 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; -- 2.19.0