gpiolib: fix off by one errors
The last gpio belonging to a chip is chip->base + chip->ngpios - 1. Some
places in the code, but not all, forgot the critical minus one.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Acked-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>
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 7f138c6..beaf6b3 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -127,7 +127,7 @@
unsigned long flags;
int i;
- if (!gpio_is_valid(start) || !gpio_is_valid(start + ngpio))
+ if (!gpio_is_valid(start) || !gpio_is_valid(start + ngpio - 1))
return -EINVAL;
spin_lock_irqsave(&gpio_lock, flags);
@@ -170,7 +170,7 @@
unsigned id;
int base = chip->base;
- if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio))
+ if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio - 1))
&& base >= 0) {
status = -EINVAL;
goto fail;
@@ -207,7 +207,7 @@
/* failures here can mean systems won't boot... */
if (status)
pr_err("gpiochip_add: gpios %d..%d (%s) not registered\n",
- chip->base, chip->base + chip->ngpio,
+ chip->base, chip->base + chip->ngpio - 1,
chip->label ? : "generic");
return status;
}