spi: dw: add support for gpio controlled chip select
Also, use this opportunity to let spi_chip_sel() handle chip-select
deactivation as well.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c
index 1492f5e..a5cba14 100644
--- a/drivers/spi/spi-dw-mmio.c
+++ b/drivers/spi/spi-dw-mmio.c
@@ -16,6 +16,7 @@
#include <linux/spi/spi.h>
#include <linux/scatterlist.h>
#include <linux/module.h>
+#include <linux/of_gpio.h>
#include "spi-dw.h"
@@ -70,6 +71,27 @@
dws->num_cs = 4;
dws->max_freq = clk_get_rate(dwsmmio->clk);
+ if (pdev->dev.of_node) {
+ int i;
+
+ for (i = 0; i < dws->num_cs; i++) {
+ int cs_gpio = of_get_named_gpio(pdev->dev.of_node,
+ "cs-gpios", i);
+
+ if (cs_gpio == -EPROBE_DEFER) {
+ ret = cs_gpio;
+ goto out;
+ }
+
+ if (gpio_is_valid(cs_gpio)) {
+ ret = devm_gpio_request(&pdev->dev, cs_gpio,
+ dev_name(&pdev->dev));
+ if (ret)
+ goto out;
+ }
+ }
+ }
+
ret = dw_spi_add_host(&pdev->dev, dws);
if (ret)
goto out;