mirror of
https://github.com/Ysurac/openmptcprouter.git
synced 2025-03-09 15:40:20 +00:00
57 lines
1.9 KiB
Diff
57 lines
1.9 KiB
Diff
From 4acdd2dc7d19b7ce3704be8f4819bf3a386a989b Mon Sep 17 00:00:00 2001
|
|
From: Phil Elwell <phil@raspberrypi.com>
|
|
Date: Wed, 12 Jan 2022 08:23:28 +0000
|
|
Subject: [PATCH 271/697] 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
|
|
@@ -34,6 +34,7 @@ struct spi_gpio {
|
|
struct gpio_desc *sck;
|
|
struct gpio_desc *miso;
|
|
struct gpio_desc *mosi;
|
|
+ bool sck_idle_input;
|
|
struct gpio_desc **cs_gpios;
|
|
};
|
|
|
|
@@ -224,8 +225,12 @@ 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) {
|
|
@@ -234,6 +239,9 @@ 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 void spi_gpio_set_mosi_idle(struct spi_device *spi)
|
|
@@ -329,6 +337,7 @@ 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);
|
|
}
|