gpiolib: gpio_to_irq() hooks

Add a new gpiolib mechanism: gpio_chip instances can provide mappings
between their (input) GPIOs and any associated IRQs.  This makes it easier
for platforms to support IRQs that are provided by board-specific external
chips instead of as part of their core (such as SOC-integrated GPIOs).

Also update the irq_to_gpio() description, saying to avoid it because it's
not always supported.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Brownell
2008-10-15 22:03:14 -07:00
committed by Linus Torvalds
parent 2f8d11971b
commit 0f6d504e73
3 changed files with 28 additions and 2 deletions

View File

@ -40,6 +40,8 @@ struct module;
* returns either the value actually sensed, or zero
* @direction_output: configures signal "offset" as output, or returns error
* @set: assigns output value for signal "offset"
* @to_irq: optional hook supporting non-static gpio_to_irq() mappings;
* implementation may not sleep
* @dbg_show: optional routine to show contents in debugfs; default code
* will be used when this is omitted, but custom code can show extra
* state (such as pullup/pulldown configuration).
@ -73,6 +75,10 @@ struct gpio_chip {
unsigned offset, int value);
void (*set)(struct gpio_chip *chip,
unsigned offset, int value);
int (*to_irq)(struct gpio_chip *chip,
unsigned offset);
void (*dbg_show)(struct seq_file *s,
struct gpio_chip *chip);
int base;
@ -112,6 +118,7 @@ extern void __gpio_set_value(unsigned gpio, int value);
extern int __gpio_cansleep(unsigned gpio);
extern int __gpio_to_irq(unsigned gpio);
#ifdef CONFIG_GPIO_SYSFS