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spi: always use software fallback for SPI_CS_WORD when using cs_gio

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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@lechnology.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
David Lechner 2018-09-18 12:08:48 -05:00 committed by Mark Brown
parent 00bca73bfc
commit 71388b2156
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GPG Key ID: 24D68B725D5487D0
1 changed files with 4 additions and 2 deletions
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6
drivers/spi/spi.c
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@ -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;