Add gpio_to_irq() implementation allowing the
gpio_chip registration to also specify an function
to map GPIO offsets into IRQs.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Index: linux-2.6.26-quilt3/drivers/gpio/gpiolib.c
===================================================================
--- linux-2.6.26-quilt3.orig/drivers/gpio/gpiolib.c 2008-07-18 00:40:52.000000000 +0100
+++ linux-2.6.26-quilt3/drivers/gpio/gpiolib.c 2008-07-18 00:47:03.000000000 +0100
@@ -339,6 +339,36 @@ const char *gpiochip_is_requested(struct
}
EXPORT_SYMBOL_GPL(gpiochip_is_requested);
+int gpio_to_irq(unsigned gpio)
+{
+ struct gpio_chip *chip;
+ struct gpio_desc *desc = &gpio_desc[gpio];
+ unsigned long flags;
+ int status = -EINVAL;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ if (!gpio_is_valid(gpio))
+ goto fail;
+
+ chip = desc->chip;
+ if (!chip || !chip->to_irq)
+ goto fail;
+
+ gpio -= chip->base;
+ if (gpio >= chip->ngpio)
+ goto fail;
+
+ status = chip->to_irq(chip, offset);
+
+ fail:
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ if (status)
+ pr_debug("%s: gpio-%d status %d\n",
+ __func__, gpio, status);
+ return status;
+}
+EXPORT_SYMBOL_GPL(gpio_to_irq);
/* Drivers MUST set GPIO direction before making get/set calls. In
* some cases this is done in early boot, before IRQs are enabled.
Index: linux-2.6.26-quilt3/include/asm-generic/gpio.h
===================================================================
--- linux-2.6.26-quilt3.orig/include/asm-generic/gpio.h 2008-07-18 00:40:52.000000000 +0100
+++ linux-2.6.26-quilt3/include/asm-generic/gpio.h 2008-07-18 00:46:32.000000000 +0100
@@ -40,6 +40,7 @@ struct module;
* @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).
+ * @to_irq: convert gpio offset to IRQ number.
* @base: identifies the first GPIO number handled by this chip; or, if
* negative during registration, requests dynamic ID allocation.
* @ngpio: the number of GPIOs handled by this controller; the last GPIO
@@ -71,6 +72,9 @@ struct gpio_chip {
unsigned offset, int value);
void (*dbg_show)(struct seq_file *s,
struct gpio_chip *chip);
+ int (*to_irq)(struct gpio_chip *chip,
+ unsigned offset);
+
int base;
u16 ngpio;
unsigned can_sleep:1;
@@ -97,6 +101,7 @@ extern int gpio_direction_output(unsigne
extern int gpio_get_value_cansleep(unsigned gpio);
extern void gpio_set_value_cansleep(unsigned gpio, int value);
+extern int gpio_to_irq(unsigned gpio);
/* A platform's <asm/gpio.h> code may want to inline the I/O calls when
* the GPIO is constant and refers to some always-present controller,
--
Ben (ben@fluff.org, http://www.fluff.org/)
'a smiley only costs 4 bytes'
--
