gpiolib: avr32 at32ap platform support

Teach AVR32 to use the "GPIO Library" when exposing its GPIOs, so that signals
on external chips (like GPIO expanders) can easily be used.

This mostly reorganizes some existing logic, with two minor changes in
behavior:

 - The PSR registers are used instead of the previous "gpio_mask" values,
   matching AT91 behavior and removing some duplication between that role
   and that of "pinmux_mask".

 - NR_IRQs grew to acommodate a bank of external GPIOs.  Eventually this
   number should probably become a board-specific config option.

There's a debugfs dump of status for the built-in GPIOs, showing which pins
have deglitching, pullups, or open drain drive enabled, as well as the ID
string used when requesting each IRQ.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Eric Miao <eric.miao@marvell.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Philipp Zabel <philipp.zabel@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 25 insertions, 9 deletions

diff --git a/include/asm-avr32/arch-at32ap/gpio.h b/include/asm-avr32/arch-at32ap/gpio.h
index af7f9535bab3..0180f584ef03 100644
--- a/include/asm-avr32/arch-at32ap/gpio.h
+++ b/include/asm-avr32/arch-at32ap/gpio.h
@@ -5,20 +5,36 @@
 #include <asm/irq.h>
 
 
-/* Arch-neutral GPIO API */
-int __must_check gpio_request(unsigned int gpio, const char *label);
-void gpio_free(unsigned int gpio);
+/* Some GPIO chips can manage IRQs; some can't.  The exact numbers can
+ * be changed if needed, but for the moment they're not configurable.
+ */
+#define ARCH_NR_GPIOS   (NR_GPIO_IRQS + 2 * 32)
 
-int gpio_direction_input(unsigned int gpio);
-int gpio_direction_output(unsigned int gpio, int value);
-int gpio_get_value(unsigned int gpio);
-void gpio_set_value(unsigned int gpio, int value);
 
-#include <asm-generic/gpio.h>           /* cansleep wrappers */
+/* Arch-neutral GPIO API, supporting both "native" and external GPIOs. */
+#include <asm-generic/gpio.h>
+
+static inline int gpio_get_value(unsigned int gpio)
+{
+        return __gpio_get_value(gpio);
+}
+
+static inline void gpio_set_value(unsigned int gpio, int value)
+{
+        __gpio_set_value(gpio, value);
+}
+
+static inline int gpio_cansleep(unsigned int gpio)
+{
+        return __gpio_cansleep(gpio);
+}
+
 
 static inline int gpio_to_irq(unsigned int gpio)
 {
-        return gpio + GPIO_IRQ_BASE;
+        if (gpio < NR_GPIO_IRQS)
+                return gpio + GPIO_IRQ_BASE;
+        return -EINVAL;
 }
 
 static inline int irq_to_gpio(unsigned int irq)