[PATCH V2 1/4] i2c: Add irq_gpio field to struct i2c_client.

[Stephen Warren <swarren@nvidia.com>]

Some devices use a single pin as both an IRQ and a GPIO. In that case,
irq_gpio is the GPIO ID for that pin. Not all drivers use this feature.
Where they do, and the use of this feature is optional, and the system
wishes to disable this feature, this field must be explicitly set to a
defined invalid GPIO ID, such as -1.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
---
v2: This patch is new. This updated series based on Arnd's comments that
this solution was a good idea.

Note that I leave on vacation for 2 weeks starting Friday afternoon. I
may have some email capabilities during this time, but will certainly be
slow to respond.

 include/linux/i2c.h |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 3fad485..b368097 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -192,6 +192,12 @@ struct i2c_driver {
  * @driver: device's driver, hence pointer to access routines
  * @dev: Driver model device node for the slave.
  * @irq: indicates the IRQ generated by this device (if any)
+ * @irq_gpio: some devices use a single pin as both an IRQ and a GPIO. In
+ *	that case, irq_gpio is the GPIO ID for that pin. Not all drivers
+ *	use this feature. Where they do, and the use of this feature is
+ *	optional, and the system wishes to disable this feature, this
+ *	field must be explicitly set to a defined invalid GPIO ID, such
+ *	as -1.
  * @detected: member of an i2c_driver.clients list or i2c-core's
  *	userspace_devices list
  *
@@ -209,6 +215,7 @@ struct i2c_client {
 	struct i2c_driver *driver;	/* and our access routines	*/
 	struct device dev;		/* the device structure		*/
 	int irq;			/* irq issued by device		*/
+	int irq_gpio;			/* gpio corresponding to irq	*/
 	struct list_head detected;
 };
 #define to_i2c_client(d) container_of(d, struct i2c_client, dev)
-- 
1.7.0.4