spi: spi-gpio: Add support for MOSI idle state configuration

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

Acked-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Link: https://patch.msgid.link/629c55a10005ba26825c3a6a19184372ef81b3e1.1720810545.git.marcelo.schmitt@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 36c587be9e2880ad60cf9ae3f42638f95e615851..4f192e013cd6f2b390f4eb21bf0456b0c3aa0fd1 100644 (file)
--- 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;
@@ -389,7 +397,8 @@ 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
                 *
@@ -414,6 +423,7 @@ 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;