Commit 95c07247 authored by Hector Martin's avatar Hector Martin Committed by Mark Brown

spi: Fix incorrect cs_setup delay handling

Move the cs_setup delay to the end of spi_set_cs.

From include/linux/spi/spi.h:

 * @cs_setup: delay to be introduced by the controller after CS is
   asserted

The cs_setup delay needs to happen *after* CS is asserted, that is, at
the end of spi_set_cs, not at the beginning. Otherwise we're just
delaying before the SPI transaction starts at all, which isn't very
useful.

No drivers use this right now, but that is likely to change soon with an
upcoming Apple SPI HID transport driver.

Fixes: 25093bde ("spi: implement SW control for CS times")
Signed-off-by: default avatarHector Martin <marcan@marcan.st>
Link: https://lore.kernel.org/r/20211210170534.177139-1-marcan@marcan.stSigned-off-by: default avatarMark Brown <broonie@kernel.org>
parent e9d7c323
......@@ -944,11 +944,8 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
spi->controller->last_cs_enable = enable;
spi->controller->last_cs_mode_high = spi->mode & SPI_CS_HIGH;
if (spi->cs_gpiod || gpio_is_valid(spi->cs_gpio) ||
!spi->controller->set_cs_timing) {
if (activate)
spi_delay_exec(&spi->cs_setup, NULL);
else
if ((spi->cs_gpiod || gpio_is_valid(spi->cs_gpio) ||
!spi->controller->set_cs_timing) && !activate) {
spi_delay_exec(&spi->cs_hold, NULL);
}
......@@ -991,7 +988,9 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
if (spi->cs_gpiod || gpio_is_valid(spi->cs_gpio) ||
!spi->controller->set_cs_timing) {
if (!activate)
if (activate)
spi_delay_exec(&spi->cs_setup, NULL);
else
spi_delay_exec(&spi->cs_inactive, NULL);
}
}
......
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