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2fd091f)
This adds a new function, of_get_gpio_flags, which is like
of_get_gpio(), but accepts a new "flags" argument. This new function
will be used by the drivers that need to retrieve additional GPIO
information, such as active-low flag.
Also, this changes the default ("simple") .xlate routine to warn about
bogus (< 2) #gpio-cells usage: the second cell should always be present
for GPIO flags.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
#include <asm/prom.h>
/**
#include <asm/prom.h>
/**
- * of_get_gpio - Get a GPIO number from the device tree to use with GPIO API
+ * of_get_gpio_flags - Get a GPIO number and flags to use with GPIO API
* @np: device node to get GPIO from
* @index: index of the GPIO
* @np: device node to get GPIO from
* @index: index of the GPIO
+ * @flags: a flags pointer to fill in
*
* Returns GPIO number to use with Linux generic GPIO API, or one of the errno
*
* Returns GPIO number to use with Linux generic GPIO API, or one of the errno
- * value on the error condition.
+ * value on the error condition. If @flags is not NULL the function also fills
+ * in flags for the GPIO.
-int of_get_gpio(struct device_node *np, int index)
+int of_get_gpio_flags(struct device_node *np, int index,
+ enum of_gpio_flags *flags)
{
int ret;
struct device_node *gc;
{
int ret;
struct device_node *gc;
- ret = of_gc->xlate(of_gc, np, gpio_spec);
+ /* .xlate might decide to not fill in the flags, so clear it. */
+ if (flags)
+ *flags = 0;
+
+ ret = of_gc->xlate(of_gc, np, gpio_spec, flags);
pr_debug("%s exited with status %d\n", __func__, ret);
return ret;
}
pr_debug("%s exited with status %d\n", __func__, ret);
return ret;
}
-EXPORT_SYMBOL(of_get_gpio);
+EXPORT_SYMBOL(of_get_gpio_flags);
- * of_gpio_simple_xlate - translate gpio_spec to the GPIO number
+ * 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
* @gpio_spec: gpio specifier as found in the device tree
* @of_gc: pointer to the of_gpio_chip structure
* @np: device node of the GPIO chip
* @gpio_spec: gpio specifier as found in the device tree
+ * @flags: a flags pointer to fill in
*
* This is simple translation function, suitable for the most 1:1 mapped
* gpio chips. This function performs only one sanity check: whether gpio
* is less than ngpios (that is specified in the gpio_chip).
*/
int of_gpio_simple_xlate(struct of_gpio_chip *of_gc, struct device_node *np,
*
* This is simple translation function, suitable for the most 1:1 mapped
* gpio chips. This function performs only one sanity check: whether gpio
* is less than ngpios (that is specified in the gpio_chip).
*/
int of_gpio_simple_xlate(struct of_gpio_chip *of_gc, struct device_node *np,
+ const void *gpio_spec, enum of_gpio_flags *flags)
{
const u32 *gpio = gpio_spec;
{
const u32 *gpio = gpio_spec;
+ /*
+ * We're discouraging gpio_cells < 2, since that way you'll have to
+ * write your own xlate function (that will have to retrive the GPIO
+ * number and the flags from a single gpio cell -- this is possible,
+ * but not recommended).
+ */
+ if (of_gc->gpio_cells < 2) {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
if (*gpio > of_gc->gc.ngpio)
return -EINVAL;
if (*gpio > of_gc->gc.ngpio)
return -EINVAL;
+ if (flags)
+ *flags = gpio[1];
+
return *gpio;
}
EXPORT_SYMBOL(of_gpio_simple_xlate);
return *gpio;
}
EXPORT_SYMBOL(of_gpio_simple_xlate);
#ifndef __LINUX_OF_GPIO_H
#define __LINUX_OF_GPIO_H
#ifndef __LINUX_OF_GPIO_H
#define __LINUX_OF_GPIO_H
+#include <linux/compiler.h>
+#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/gpio.h>
#include <linux/errno.h>
#include <linux/gpio.h>
+struct device_node;
+
+/*
+ * This is Linux-specific flags. By default controllers' and Linux' mapping
+ * match, but GPIO controllers are free to translate their own flags to
+ * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
+ */
+enum of_gpio_flags {
+ OF_GPIO_ACTIVE_LOW = 0x1,
+};
+
struct gpio_chip gc;
int gpio_cells;
int (*xlate)(struct of_gpio_chip *of_gc, struct device_node *np,
struct gpio_chip gc;
int gpio_cells;
int (*xlate)(struct of_gpio_chip *of_gc, struct device_node *np,
- const void *gpio_spec);
+ const void *gpio_spec, enum of_gpio_flags *flags);
};
static inline struct of_gpio_chip *to_of_gpio_chip(struct gpio_chip *gc)
};
static inline struct of_gpio_chip *to_of_gpio_chip(struct gpio_chip *gc)
return container_of(of_gc, struct of_mm_gpio_chip, of_gc);
}
return container_of(of_gc, struct of_mm_gpio_chip, of_gc);
}
-extern int of_get_gpio(struct device_node *np, int index);
+extern int of_get_gpio_flags(struct device_node *np, int index,
+ enum of_gpio_flags *flags);
+
extern int of_mm_gpiochip_add(struct device_node *np,
struct of_mm_gpio_chip *mm_gc);
extern int of_gpio_simple_xlate(struct of_gpio_chip *of_gc,
struct device_node *np,
extern int of_mm_gpiochip_add(struct device_node *np,
struct of_mm_gpio_chip *mm_gc);
extern int of_gpio_simple_xlate(struct of_gpio_chip *of_gc,
struct device_node *np,
- const void *gpio_spec);
+ const void *gpio_spec,
+ enum of_gpio_flags *flags);
#else
/* Drivers may not strictly depend on the GPIO support, so let them link. */
#else
/* Drivers may not strictly depend on the GPIO support, so let them link. */
-static inline int of_get_gpio(struct device_node *np, int index)
+static inline int of_get_gpio_flags(struct device_node *np, int index,
+ enum of_gpio_flags *flags)
{
return -ENOSYS;
}
#endif /* CONFIG_OF_GPIO */
{
return -ENOSYS;
}
#endif /* CONFIG_OF_GPIO */
+/**
+ * of_get_gpio - Get a GPIO number to use with GPIO API
+ * @np: device node to get GPIO from
+ * @index: index of the GPIO
+ *
+ * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
+ * value on the error condition.
+ */
+static inline int of_get_gpio(struct device_node *np, int index)
+{
+ return of_get_gpio_flags(np, index, NULL);
+}
+
#endif /* __LINUX_OF_GPIO_H */
#endif /* __LINUX_OF_GPIO_H */