[PATCH v3 3/6] spi: spi-gpio: Add support for MOSI idle state configuration

[Marcelo Schmitt <marcelo.schmitt@analog.com>]

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

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
---
 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