openwrt/target/linux/bcm27xx/patches-6.1/950-0227-spi-Force-CS_HIGH-if-GPIO-descriptors-are-used.patch
John Audia 4a0839b44e kernel: bump 6.1 to 6.1.76
Changelog: https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.1.76

All patches automatically rebased.

Build system: x86/64
Build-tested: x86/64/AMD Cezanne
Run-tested: x86/64/AMD Cezanne

Signed-off-by: John Audia <therealgraysky@proton.me>
2024-02-08 18:35:42 +01:00

58 lines
2.0 KiB
Diff

From 51a164a0654895d930acb4e3bd096f7bf54c058b Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.com>
Date: Fri, 17 Apr 2020 10:46:19 +0100
Subject: [PATCH] spi: Force CS_HIGH if GPIO descriptors are used
Commit f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
amended of_spi_parse_dt() to always set SPI_CS_HIGH for SPI slaves whose
Chip Select is defined by a "cs-gpios" devicetree property.
This change breaks drivers whose probe functions set the mode field of
the spi_device because in doing so they clear the SPI_CS_HIGH flag.
Fix by setting SPI_CS_HIGH in spi_setup (under the same conditions as
in of_spi_parse_dt()).
See also: 83b2a8fe43bd ("spi: spidev: Fix CS polarity if GPIO descriptors are used")
Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
SQUASH: spi: Demote SPI_CS_HIGH warning to KERN_DEBUG
This warning is unavoidable from a client's perspective and
doesn't indicate anything wrong (just surprising).
SQUASH with "spi: use_gpio_descriptor fixup moved to spi_setup"
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
---
drivers/spi/spi.c | 9 +++++++++
1 file changed, 9 insertions(+)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -3679,6 +3679,7 @@ static int spi_set_cs_timing(struct spi_
*/
int spi_setup(struct spi_device *spi)
{
+ struct spi_controller *ctlr = spi->controller;
unsigned bad_bits, ugly_bits;
int status = 0;
@@ -3699,6 +3700,14 @@ int spi_setup(struct spi_device *spi)
(SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL |
SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL)))
return -EINVAL;
+
+ if (ctlr->use_gpio_descriptors && ctlr->cs_gpiods &&
+ ctlr->cs_gpiods[spi->chip_select] && !(spi->mode & SPI_CS_HIGH)) {
+ dev_dbg(&spi->dev,
+ "setup: forcing CS_HIGH (use_gpio_descriptors)\n");
+ spi->mode |= SPI_CS_HIGH;
+ }
+
/*
* Help drivers fail *cleanly* when they need options
* that aren't supported with their current controller.