[PATCH 6.8 641/715] spi: Restore delays for non-GPIO chip select

Sasha Levin
2024-03-24T22:45:33Z

From: Janne Grunau <j@jannau.net>

[ Upstream commit aa0162dc0dd95c3bf248e3c78068760094e8f64b ]

SPI controller with integrated chip select handling still need to adhere
to SPI device's CS setup, hold and inactive delays. For controller
without set_cs_timing spi core shall handle the delays to avoid
duplicated delay handling in each controller driver.
Fixes a regression for the out of tree SPI controller and SPI HID
transport on Apple M1/M1 Pro/Max notebooks.

Fixes: 4d8ff6b0991d ("spi: Add multi-cs memories support in SPI core")
Signed-off-by: Janne Grunau <j@jannau.net>
Link: https://msgid.link/r/20240311-spi-cs-delays-regression-v1-1-0075020a90b2@jannau.net
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index d1b297f438f14..46f1535487608 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1042,10 +1042,14 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
if (spi->mode & SPI_CS_HIGH)
enable = !enable;

- if (spi_is_csgpiod(spi)) {
- if (!spi->controller->set_cs_timing && !activate)
- spi_delay_exec(&spi->cs_hold, NULL);
+ /*
+ * Handle chip select delays for GPIO based CS or controllers without
+ * programmable chip select timing.
+ */
+ if ((spi_is_csgpiod(spi) || !spi->controller->set_cs_timing) && !activate)
+ spi_delay_exec(&spi->cs_hold, NULL);

+ if (spi_is_csgpiod(spi)) {
if (!(spi->mode & SPI_NO_CS)) {
/*
* Historically ACPI has no means of the GPIO polarity and
@@ -1079,16 +1083,16 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
if ((spi->controller->flags & SPI_CONTROLLER_GPIO_SS) &&
spi->controller->set_cs)
spi->controller->set_cs(spi, !enable);
-
- if (!spi->controller->set_cs_timing) {
- if (activate)
- spi_delay_exec(&spi->cs_setup, NULL);
- else
- spi_delay_exec(&spi->cs_inactive, NULL);
- }
} else if (spi->controller->set_cs) {
spi->controller->set_cs(spi, !enable);
}
+
+ if (spi_is_csgpiod(spi) || !spi->controller->set_cs_timing) {
+ if (activate)
+ spi_delay_exec(&spi->cs_setup, NULL);
+ else
+ spi_delay_exec(&spi->cs_inactive, NULL);
+ }
}

#ifdef CONFIG_HAS_DMA
--
2.43.0