mirror of
git://git.openwrt.org/openwrt/openwrt.git
synced 2024-12-24 15:43:25 +00:00
58 lines
2.0 KiB
Diff
58 lines
2.0 KiB
Diff
|
From 43840b26213fb0522ab464e9a31f148122acaa80 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
|
||
|
@@ -3469,6 +3469,7 @@ static int __spi_validate_bits_per_word(
|
||
|
*/
|
||
|
int spi_setup(struct spi_device *spi)
|
||
|
{
|
||
|
+ struct spi_controller *ctlr = spi->controller;
|
||
|
unsigned bad_bits, ugly_bits;
|
||
|
int status;
|
||
|
|
||
|
@@ -3490,6 +3491,14 @@ 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
|
||
|
* SPI_CS_WORD has a fallback software implementation,
|