Merge tag 'spi-fix-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

[sfrench/cifs-2.6.git] / drivers / gpio / gpiolib-of.c

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index dc27b1a88e9343a8a029832cef5c6095a7be6238..b696e4598a240ea4237bacf42d90b22424320616 100644 (file)
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -23,6 +23,29 @@
 #include "gpiolib.h"
 #include "gpiolib-of.h"
 
+/**
+ * of_gpio_spi_cs_get_count() - special GPIO counting for SPI
+ * Some elder GPIO controllers need special quirks. Currently we handle
+ * the Freescale GPIO controller with bindings that doesn't use the
+ * established "cs-gpios" for chip selects but instead rely on
+ * "gpios" for the chip select lines. If we detect this, we redirect
+ * the counting of "cs-gpios" to count "gpios" transparent to the
+ * driver.
+ */
+static int of_gpio_spi_cs_get_count(struct device *dev, const char *con_id)
+{
+       struct device_node *np = dev->of_node;
+
+       if (!IS_ENABLED(CONFIG_SPI_MASTER))
+               return 0;
+       if (!con_id || strcmp(con_id, "cs"))
+               return 0;
+       if (!of_device_is_compatible(np, "fsl,spi") &&
+           !of_device_is_compatible(np, "aeroflexgaisler,spictrl"))
+               return 0;
+       return of_gpio_named_count(np, "gpios");
+}
+
 /*
  * This is used by external users of of_gpio_count() from <linux/of_gpio.h>
  *
@@ -35,6 +58,10 @@ int of_gpio_get_count(struct device *dev, const char *con_id)
        char propname[32];
        unsigned int i;
 
+       ret = of_gpio_spi_cs_get_count(dev, con_id);
+       if (ret > 0)
+               return ret;
+
        for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
                if (con_id)
                        snprintf(propname, sizeof(propname), "%s-%s",