spi: spi-gpio: Add checks for the dt properties
The bindings assumed that the gpios properties were always there, which
made the NO_TX and NO_RX mode not usable from device tree. Add extra
checks to make sure that the driver can work if either MOSI or MISO is
not used.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index c7cf0b7..9ddef55 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -365,9 +365,26 @@
if (!pdata)
return -ENOMEM;
- pdata->sck = of_get_named_gpio(np, "gpio-sck", 0);
- pdata->miso = of_get_named_gpio(np, "gpio-miso", 0);
- pdata->mosi = of_get_named_gpio(np, "gpio-mosi", 0);
+ ret = of_get_named_gpio(np, "gpio-sck", 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "gpio-sck property not found\n");
+ goto error_free;
+ }
+ pdata->sck = ret;
+
+ ret = of_get_named_gpio(np, "gpio-miso", 0);
+ if (ret < 0) {
+ dev_info(&pdev->dev, "gpio-miso property not found, switching to no-rx mode\n");
+ pdata->miso = SPI_GPIO_NO_MISO;
+ } else
+ pdata->miso = ret;
+
+ ret = of_get_named_gpio(np, "gpio-mosi", 0);
+ if (ret < 0) {
+ dev_info(&pdev->dev, "gpio-mosi property not found, switching to no-tx mode\n");
+ pdata->mosi = SPI_GPIO_NO_MOSI;
+ } else
+ pdata->mosi = ret;
ret = of_property_read_u32(np, "num-chipselects", &tmp);
if (ret < 0) {