gpio: Fix ngpio in gpio-xilinx driver
If one adds gpio-controller; to the chip in the devicetree, then
initialization fails with 'gpiochip_find_base: cannot find free range',
because ngpio is 0. This patch fixes the bug.
This version includes the suggestions from Linus Walleij.
Tested on ml507 board.
Signed-off-by: Gernot Vormayr <gvormayr@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index 1248186..ba18b06 100644
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -197,6 +197,7 @@
struct xgpio_instance *chip;
int status = 0;
const u32 *tree_info;
+ u32 ngpio;
chip = kzalloc(sizeof(*chip), GFP_KERNEL);
if (!chip)
@@ -211,12 +212,13 @@
/* Update GPIO direction shadow register with default value */
of_property_read_u32(np, "xlnx,tri-default", &chip->gpio_dir);
- /* By default assume full GPIO controller */
- chip->mmchip.gc.ngpio = 32;
-
- /* Check device node and parent device node for device width */
- of_property_read_u32(np, "xlnx,gpio-width",
- (u32 *)&chip->mmchip.gc.ngpio);
+ /*
+ * Check device node and parent device node for device width
+ * and assume default width of 32
+ */
+ if (of_property_read_u32(np, "xlnx,gpio-width", &ngpio))
+ ngpio = 32;
+ chip->mmchip.gc.ngpio = (u16)ngpio;
spin_lock_init(&chip->gpio_lock);
@@ -258,12 +260,13 @@
/* Update GPIO direction shadow register with default value */
of_property_read_u32(np, "xlnx,tri-default-2", &chip->gpio_dir);
- /* By default assume full GPIO controller */
- chip->mmchip.gc.ngpio = 32;
-
- /* Check device node and parent device node for device width */
- of_property_read_u32(np, "xlnx,gpio2-width",
- (u32 *)&chip->mmchip.gc.ngpio);
+ /*
+ * Check device node and parent device node for device width
+ * and assume default width of 32
+ */
+ if (of_property_read_u32(np, "xlnx,gpio2-width", &ngpio))
+ ngpio = 32;
+ chip->mmchip.gc.ngpio = (u16)ngpio;
spin_lock_init(&chip->gpio_lock);