[PATCH v2] AT91: pio: add gpio_is_valid() function

From: Nicolas Ferre
Date: Mon Sep 06 2010 - 09:16:58 EST


Add a simple gpio_is_valid() function to overload
the standard one. It takes into account the AT91
pio numbering to check if a proper value is used.
The upper limit keeps room for IO expanders above
regular on-chip GPIO numbers.

Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@xxxxxxxxxxxx>
---
Changes since v1:
define ARCH_NR_GPIOS for AT91 keeping room for IO expanders
now use an upper limit to conform with gpiolib

arch/arm/mach-at91/include/mach/gpio.h | 14 ++++++++++++++
include/asm-generic/gpio.h | 4 ++++
2 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-at91/include/mach/gpio.h b/arch/arm/mach-at91/include/mach/gpio.h
index bfdd8ab..55828ad 100644
--- a/arch/arm/mach-at91/include/mach/gpio.h
+++ b/arch/arm/mach-at91/include/mach/gpio.h
@@ -21,6 +21,10 @@
#define MAX_GPIO_BANKS 5
#define NR_BUILTIN_GPIO (PIN_BASE + (MAX_GPIO_BANKS * 32))

+/* keep room for a couple of GPIO expanders */
+#define NR_EXTRA_GPIO 64
+#define ARCH_NR_GPIOS (NR_BUILTIN_GPIO + NR_EXTRA_GPIO)
+
/* these pin numbers double as IRQ numbers, like AT91xxx_ID_* values */

#define AT91_PIN_PA0 (PIN_BASE + 0x00 + 0)
@@ -189,6 +193,16 @@
#define AT91_PIN_PE31 (PIN_BASE + 0x80 + 31)

#ifndef __ASSEMBLY__
+static inline int gpio_is_valid(int number)
+{
+ if (number >= PIN_BASE &&
+ number <= ARCH_NR_GPIOS)
+ return 1;
+ return 0;
+}
+#define __HAVE_ARCH_GPIO_IS_VALID 1
+
+
/* setup setup routines, called from board init or driver probe() */
extern int __init_or_module at91_set_GPIO_periph(unsigned pin, int use_pullup);
extern int __init_or_module at91_set_A_periph(unsigned pin, int use_pullup);
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index c7376bf..264e701 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -22,11 +22,13 @@
#define ARCH_NR_GPIOS 256
#endif

+#ifndef __HAVE_ARCH_GPIO_IS_VALID
static inline int gpio_is_valid(int number)
{
/* only some non-negative numbers are valid */
return ((unsigned)number) < ARCH_NR_GPIOS;
}
+#endif

struct device;
struct seq_file;
@@ -200,11 +202,13 @@ extern void gpio_unexport(unsigned gpio);

#else /* !CONFIG_HAVE_GPIO_LIB */

+#ifndef __HAVE_ARCH_GPIO_IS_VALID
static inline int gpio_is_valid(int number)
{
/* only non-negative numbers are valid */
return number >= 0;
}
+#endif

/* platforms that don't directly support access to GPIOs through I2C, SPI,
* or other blocking infrastructure can use these wrappers.
--
1.5.6.5

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