diff options
| author | Linus Walleij <linus.walleij@linaro.org> | 2015-12-03 17:14:13 +0300 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2016-01-05 13:20:12 +0300 |
| commit | b08ea35a3296ee25c4cb53a977b752266dafa2c2 (patch) | |
| tree | ac2742730a0b73af246fdf71247c45e7f704a61c /include/linux/gpio | |
| parent | 41d107ad92b4b8abf103b62269c34da80320f212 (diff) | |
| download | linux-b08ea35a3296ee25c4cb53a977b752266dafa2c2.tar.xz | |
gpio: add a data pointer to gpio_chip
This adds a void * pointer to gpio_chip so that driver can
assign and retrieve some states. This is done to get rid of
container_of() calls for gpio_chips embedded inside state
containers, so we can remove the need to have the gpio_chip
or later (planned) struct gpio_device be dynamically allocated
at registration time, so that its struct device can be properly
reference counted and not bound to its parent device (e.g.
a platform_device) but instead live on after unregistration
if it is opened by e.g. a char device or sysfs.
The data is added with the new function gpiochip_add_data()
and for compatibility we add static inline wrapper function
gpiochip_add() that will call gpiochip_add_data() with
NULL as argument. The latter will be removed once we have
exorcised gpiochip_add() from the kernel.
gpiochip_get_data() is added as a static inline accessor
for drivers to quickly get their data out.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'include/linux/gpio')
| -rw-r--r-- | include/linux/gpio/driver.h | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 990797589408..b833a5f9629a 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -23,6 +23,7 @@ struct seq_file; * @parent: optional parent device providing the GPIOs * @cdev: class device used by sysfs interface (may be NULL) * @owner: helps prevent removal of modules exporting active GPIOs + * @data: per-instance data assigned by the driver * @list: links gpio_chips together for traversal * @request: optional hook for chip-specific activation, such as * enabling module power and clock; may sleep @@ -91,6 +92,7 @@ struct gpio_chip { struct device *parent; struct device *cdev; struct module *owner; + void *data; struct list_head list; int (*request)(struct gpio_chip *chip, @@ -165,7 +167,11 @@ extern const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset); /* add/remove chips */ -extern int gpiochip_add(struct gpio_chip *chip); +extern int gpiochip_add_data(struct gpio_chip *chip, void *data); +static inline int gpiochip_add(struct gpio_chip *chip) +{ + return gpiochip_add_data(chip, NULL); +} extern void gpiochip_remove(struct gpio_chip *chip); extern struct gpio_chip *gpiochip_find(void *data, int (*match)(struct gpio_chip *chip, void *data)); @@ -174,6 +180,12 @@ extern struct gpio_chip *gpiochip_find(void *data, int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset); void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset); +/* get driver data */ +static inline void *gpiochip_get_data(struct gpio_chip *chip) +{ + return chip->data; +} + struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc); #ifdef CONFIG_GPIOLIB_IRQCHIP |