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authorKent Gibson <warthog618@gmail.com>2019-11-05 03:04:28 +0100
committerBartosz Golaszewski <bgolaszewski@baylibre.com>2019-11-12 16:30:30 +0100
commitb043ed7ef0b358d7f32dc57c218f925fd2802aba (patch)
tree4bb5908837de41b0a9505e3ec73ea361ad140372 /drivers
parentgpio: mockup: add set_config to support pull up/down (diff)
downloadlinux-b043ed7ef0b358d7f32dc57c218f925fd2802aba.tar.xz
linux-b043ed7ef0b358d7f32dc57c218f925fd2802aba.zip
gpiolib: move validation of line handle flags into helper function
Move validation of line handle flags into helper function. This reduces the size and complexity of linehandle_create and allows the validation to be reused elsewhere. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/gpio/gpiolib.c93
1 files changed, 51 insertions, 42 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index be159f56ff45..a9826627f347 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -428,6 +428,54 @@ struct linehandle_state {
GPIOHANDLE_REQUEST_OPEN_DRAIN | \
GPIOHANDLE_REQUEST_OPEN_SOURCE)
+static int linehandle_validate_flags(u32 flags)
+{
+ /* Return an error if an unknown flag is set */
+ if (flags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
+ return -EINVAL;
+
+ /*
+ * Do not allow both INPUT & OUTPUT flags to be set as they are
+ * contradictory.
+ */
+ if ((flags & GPIOHANDLE_REQUEST_INPUT) &&
+ (flags & GPIOHANDLE_REQUEST_OUTPUT))
+ return -EINVAL;
+
+ /*
+ * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
+ * the hardware actually supports enabling both at the same time the
+ * electrical result would be disastrous.
+ */
+ if ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
+ (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
+ return -EINVAL;
+
+ /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
+ if (!(flags & GPIOHANDLE_REQUEST_OUTPUT) &&
+ ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
+ (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
+ return -EINVAL;
+
+ /* Bias flags only allowed for input or output mode. */
+ if (!((flags & GPIOHANDLE_REQUEST_INPUT) ||
+ (flags & GPIOHANDLE_REQUEST_OUTPUT)) &&
+ ((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||
+ (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||
+ (flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
+ return -EINVAL;
+
+ /* Only one bias flag can be set. */
+ if (((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
+ (flags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
+ GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
+ ((flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
+ (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
+ return -EINVAL;
+
+ return 0;
+}
+
static long linehandle_ioctl(struct file *filep, unsigned int cmd,
unsigned long arg)
{
@@ -529,48 +577,9 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
lflags = handlereq.flags;
- /* Return an error if an unknown flag is set */
- if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
- return -EINVAL;
-
- /*
- * Do not allow both INPUT & OUTPUT flags to be set as they are
- * contradictory.
- */
- if ((lflags & GPIOHANDLE_REQUEST_INPUT) &&
- (lflags & GPIOHANDLE_REQUEST_OUTPUT))
- return -EINVAL;
-
- /*
- * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
- * the hardware actually supports enabling both at the same time the
- * electrical result would be disastrous.
- */
- if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
- (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
- return -EINVAL;
-
- /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
- if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) &&
- ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
- (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
- return -EINVAL;
-
- /* Bias flags only allowed for input or output mode. */
- if (!((lflags & GPIOHANDLE_REQUEST_INPUT) ||
- (lflags & GPIOHANDLE_REQUEST_OUTPUT)) &&
- ((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||
- (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||
- (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
- return -EINVAL;
-
- /* Only one bias flag can be set. */
- if (((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
- (lflags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
- GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
- ((lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
- (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
- return -EINVAL;
+ ret = linehandle_validate_flags(lflags);
+ if (ret)
+ return ret;
lh = kzalloc(sizeof(*lh), GFP_KERNEL);
if (!lh)