mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-20 22:23:27 +00:00
20ea6adbf1
Build system: x86_64 Build-tested: bcm2708, bcm2709, bcm2710, bcm2711 Run-tested: bcm2708/RPiB+, bcm2709/RPi3B, bcm2710/RPi3B, bcm2711/RPi4B Signed-off-by: Marty Jones <mj8263788@gmail.com> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
58 lines
1.9 KiB
Diff
58 lines
1.9 KiB
Diff
From c979072887ef70aab2ab6e71544853df71017925 Mon Sep 17 00:00:00 2001
|
|
From: Phil Elwell <phil@raspberrypi.com>
|
|
Date: Wed, 12 Jan 2022 08:23:28 +0000
|
|
Subject: [PATCH] spi: gpio: Add sck-idle-input property
|
|
|
|
The sck-idle-input property indicates that the spi-gpio driver should
|
|
return the SCK line to an input when the chip select signals are
|
|
inactive.
|
|
|
|
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
|
|
---
|
|
drivers/spi/spi-gpio.c | 13 +++++++++++--
|
|
1 file changed, 11 insertions(+), 2 deletions(-)
|
|
|
|
--- a/drivers/spi/spi-gpio.c
|
|
+++ b/drivers/spi/spi-gpio.c
|
|
@@ -35,6 +35,7 @@ struct spi_gpio {
|
|
struct gpio_desc *sck;
|
|
struct gpio_desc *miso;
|
|
struct gpio_desc *mosi;
|
|
+ bool sck_idle_input;
|
|
struct gpio_desc **cs_gpios;
|
|
};
|
|
|
|
@@ -201,8 +202,12 @@ static void spi_gpio_chipselect(struct s
|
|
struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
|
|
|
|
/* set initial clock line level */
|
|
- if (is_active)
|
|
- gpiod_set_value_cansleep(spi_gpio->sck, spi->mode & SPI_CPOL);
|
|
+ if (is_active) {
|
|
+ if (spi_gpio->sck_idle_input)
|
|
+ gpiod_direction_output(spi_gpio->sck, spi->mode & SPI_CPOL);
|
|
+ else
|
|
+ gpiod_set_value_cansleep(spi_gpio->sck, spi->mode & SPI_CPOL);
|
|
+ }
|
|
|
|
/* Drive chip select line, if we have one */
|
|
if (spi_gpio->cs_gpios) {
|
|
@@ -211,6 +216,9 @@ static void spi_gpio_chipselect(struct s
|
|
/* SPI chip selects are normally active-low */
|
|
gpiod_set_value_cansleep(cs, (spi->mode & SPI_CS_HIGH) ? is_active : !is_active);
|
|
}
|
|
+
|
|
+ if (spi_gpio->sck_idle_input && !is_active)
|
|
+ gpiod_direction_input(spi_gpio->sck);
|
|
}
|
|
|
|
static int spi_gpio_setup(struct spi_device *spi)
|
|
@@ -289,6 +297,7 @@ static int spi_gpio_request(struct devic
|
|
if (IS_ERR(spi_gpio->miso))
|
|
return PTR_ERR(spi_gpio->miso);
|
|
|
|
+ spi_gpio->sck_idle_input = device_property_read_bool(dev, "sck-idle-input");
|
|
spi_gpio->sck = devm_gpiod_get(dev, "sck", GPIOD_OUT_LOW);
|
|
return PTR_ERR_OR_ZERO(spi_gpio->sck);
|
|
}
|