[PATCH v7 3/7] spi: spi-gpio: Add support for MOSI idle state configuration

From: Marcelo Schmitt
Date: Fri Jul 12 2024 - 15:22:10 EST


Implement MOSI idle low and MOSI idle high to better support peripherals
that request specific MOSI behavior.

Acked-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
Reviewed-by: David Lechner <dlechner@xxxxxxxxxxxx>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
---
drivers/spi/spi-gpio.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 909cce109bba..d3b8c99f0cb4 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -236,6 +236,14 @@ static void spi_gpio_chipselect(struct spi_device *spi, int is_active)
}
}

+static void spi_gpio_set_mosi_idle(struct spi_device *spi)
+{
+ struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
+
+ gpiod_set_value_cansleep(spi_gpio->mosi,
+ !!(spi->mode & SPI_MOSI_IDLE_HIGH));
+}
+
static int spi_gpio_setup(struct spi_device *spi)
{
struct gpio_desc *cs;
@@ -411,7 +419,8 @@ static int spi_gpio_probe(struct platform_device *pdev)

host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
host->mode_bits = SPI_3WIRE | SPI_3WIRE_HIZ | SPI_CPHA | SPI_CPOL |
- SPI_CS_HIGH | SPI_LSB_FIRST;
+ SPI_CS_HIGH | SPI_LSB_FIRST | SPI_MOSI_IDLE_LOW |
+ SPI_MOSI_IDLE_HIGH;
if (!spi_gpio->mosi) {
/* HW configuration without MOSI pin
*
@@ -436,6 +445,7 @@ static int spi_gpio_probe(struct platform_device *pdev)
host->flags |= SPI_CONTROLLER_GPIO_SS;
bb->chipselect = spi_gpio_chipselect;
bb->set_line_direction = spi_gpio_set_direction;
+ bb->set_mosi_idle = spi_gpio_set_mosi_idle;

if (host->flags & SPI_CONTROLLER_NO_TX) {
bb->txrx_word[SPI_MODE_0] = spi_gpio_spec_txrx_word_mode0;
--
2.43.0