gpio: clamp values on gpio[d]_direction_output()

I saw weird values != [0,1] being passed down to drivers
in their .set_direction_output() callbacks. Go over the
gpiolib and make sure to hammer it to [0,1] before hitting
the driver to avoid undesired side effects.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 8 insertions, 5 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f0fc3a0d37c8..b7452c5223be 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2150,6 +2150,7 @@ EXPORT_SYMBOL_GPL(gpiod_direction_input);
 static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
 {
         struct gpio_chip *gc = desc->gdev->chip;
+        int val = !!value;
         int ret;
 
         /* GPIOs used for IRQs shall not be set as output */
@@ -2169,7 +2170,7 @@ static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
                                 goto set_output_value;
                 }
                 /* Emulate open drain by not actively driving the line high */
-                if (value)
+                if (val)
                         return gpiod_direction_input(desc);
         }
         else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
@@ -2180,7 +2181,7 @@ static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
                                 goto set_output_value;
                 }
                 /* Emulate open source by not actively driving the line low */
-                if (!value)
+                if (!val)
                         return gpiod_direction_input(desc);
         } else {
                 /* Make sure to disable open drain/source hardware, if any */
@@ -2198,10 +2199,10 @@ set_output_value:
                 return -EIO;
         }
 
-        ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), value);
+        ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
         if (!ret)
                 set_bit(FLAG_IS_OUT, &desc->flags);
-        trace_gpio_value(desc_to_gpio(desc), 0, value);
+        trace_gpio_value(desc_to_gpio(desc), 0, val);
         trace_gpio_direction(desc_to_gpio(desc), 0, ret);
         return ret;
 }
@@ -2241,6 +2242,8 @@ int gpiod_direction_output(struct gpio_desc *desc, int value)
         VALIDATE_DESC(desc);
         if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
                 value = !value;
+        else
+                value = !!value;
         return _gpiod_direction_output_raw(desc, value);
 }
 EXPORT_SYMBOL_GPL(gpiod_direction_output);
@@ -3094,7 +3097,7 @@ static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
         /* Process flags */
         if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
                 status = gpiod_direction_output(desc,
-                                              dflags & GPIOD_FLAGS_BIT_DIR_VAL);
+                                !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
         else
                 status = gpiod_direction_input(desc);