This function is used to count how many GPIOs are specified for
a device node.
Signed-off-by: Anton Vorontsov <[EMAIL PROTECTED]>
---
drivers/of/gpio.c | 34 ++++++++++++++++++++++++++++++++++
include/linux/of_gpio.h | 6 ++++++
2 files changed, 40 insertions(+), 0 deletions(-)
diff --git a/drivers/of/gpio.c b/drivers/of/gpio.c
index a4ba217..6eea601 100644
--- a/drivers/of/gpio.c
+++ b/drivers/of/gpio.c
@@ -80,6 +80,40 @@ err0:
EXPORT_SYMBOL(of_get_gpio_flags);
/**
+ * of_gpio_count - Count GPIOs for a device
+ * @np: device node to count GPIOs for
+ *
+ * The function returns the count of GPIOs specified for a node.
+ *
+ * Note that the empty GPIO specifiers counts too. For example,
+ *
+ * gpios = <0
+ * &pio1 1 2
+ * 0
+ * &pio2 3 4>;
+ *
+ * defines four GPIOs (so this function will return 4), two of which
+ * are not specified.
+ */
+unsigned int of_gpio_count(struct device_node *np)
+{
+ unsigned int cnt = 0;
+
+ do {
+ int ret;
+
+ ret = of_parse_phandles_with_args(np, "gpios", "#gpio-cells",
+ cnt, NULL, NULL);
+ /* A hole in the gpios = <> counts anyway. */
+ if (ret < 0 && ret != -EEXIST)
+ break;
+ } while (++cnt);
+
+ return cnt;
+}
+EXPORT_SYMBOL(of_gpio_count);
+
+/**
* of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
* @of_gc: pointer to the of_gpio_chip structure
* @np: device node of the GPIO chip
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index e25abf6..fc2472c 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -65,6 +65,7 @@ static inline struct of_mm_gpio_chip
*to_of_mm_gpio_chip(struct gpio_chip *gc)
extern int of_get_gpio_flags(struct device_node *np, int index,
enum of_gpio_flags *flags);
+extern unsigned int of_gpio_count(struct device_node *np);
extern int of_mm_gpiochip_add(struct device_node *np,
struct of_mm_gpio_chip *mm_gc);
@@ -81,6 +82,11 @@ static inline int of_get_gpio_flags(struct device_node *np,
int index,
return -ENOSYS;
}
+static inline unsigned int of_gpio_count(struct device_node *np)
+{
+ return 0;
+}
+
#endif /* CONFIG_OF_GPIO */
/**
--
1.5.6.5
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