From: Drew Fustini <drew@pdp7.com>
To: warthog618@gmail.com
Cc: linux-gpio@vger.kernel.org, linus.walleij@linaro.org,
brgl@bgdev.pl, Drew Fustini <drew@pdp7.com>
Subject: Re: [RFC] gpio: expose pull-up/pull-down line flags to userspace
Date: Wed, 9 Oct 2019 13:32:33 +0200 [thread overview]
Message-ID: <20191009113232.28852-1-drew@pdp7.com> (raw)
In-Reply-To: <20191009002211.GA11168@sol>
set pull-up/down flags in lineevent_create and add sanity checks
Check the pull-up/down flags in lineevent_create() and set the
corresponding bits.
Add sanity checks to make pull-up and pull-down flags mutually
exclusive and only valid when the line is an input.
Signed-off-by: Drew Fustini <drew@pdp7.com>
---
drivers/gpio/gpiolib.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 646ae4cffe26..babc26267561 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -554,6 +554,20 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
(lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
return -EINVAL;
+ /*
+ * Do not allow PULL_UP & PULL_DOWN flags to be set as they are
+ * contradictory.
+ */
+ if ((lflags & GPIOHANDLE_REQUEST_PULL_UP) &&
+ (lflags & GPIOHANDLE_REQUEST_PULL_DOWN))
+ return -EINVAL;
+
+ /* PULL_UP and PULL_DOWN flags only make sense for input mode. */
+ if (!(lflags & GPIOHANDLE_REQUEST_INPUT) &&
+ ((lflags & GPIOHANDLE_REQUEST_PULL_UP) ||
+ (lflags & GPIOHANDLE_REQUEST_PULL_DOWN)))
+ return -EINVAL;
+
lh = kzalloc(sizeof(*lh), GFP_KERNEL);
if (!lh)
return -ENOMEM;
@@ -941,6 +955,24 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
goto out_free_label;
}
+ /*
+ * Do not allow PULL_UP & PULL_DOWN flags to be set as they are
+ * contradictory.
+ */
+ if ((lflags & GPIOHANDLE_REQUEST_PULL_UP) &&
+ (lflags & GPIOHANDLE_REQUEST_PULL_DOWN)) {
+ ret = -EINVAL;
+ goto out_free_label;
+ }
+
+ /* PULL_UP and PULL_DOWN flags only make sense for input mode. */
+ if (!(lflags & GPIOHANDLE_REQUEST_INPUT) &&
+ ((lflags & GPIOHANDLE_REQUEST_PULL_UP) ||
+ (lflags & GPIOHANDLE_REQUEST_PULL_DOWN))) {
+ ret = -EINVAL;
+ goto out_free_label;
+ }
+
desc = &gdev->descs[offset];
ret = gpiod_request(desc, le->label);
if (ret)
@@ -950,6 +982,10 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
set_bit(FLAG_ACTIVE_LOW, &desc->flags);
+ if (lflags & GPIO_PULL_UP)
+ set_bit(FLAG_PULL_UP, &desc->flags);
+ else if (lflags & GPIO_PULL_DOWN)
+ set_bit(FLAG_PULL_DOWN, &desc->flags);
ret = gpiod_direction_input(desc);
if (ret)
--
2.20.1
next prev parent reply other threads:[~2019-10-09 11:38 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-21 10:25 [RFC] gpio: expose pull-up/pull-down line flags to userspace Drew Fustini
2019-09-23 8:38 ` Bartosz Golaszewski
2019-10-02 11:10 ` Drew Fustini
2019-10-03 12:47 ` Linus Walleij
2019-10-04 7:22 ` Bartosz Golaszewski
2019-10-04 12:46 ` Bartosz Golaszewski
2019-10-05 17:02 ` Linus Walleij
2019-10-06 3:12 ` Kent Gibson
2019-10-06 21:06 ` Linus Walleij
2019-10-07 4:37 ` Kent Gibson
2019-10-08 6:15 ` Kent Gibson
2019-10-08 20:56 ` Bartosz Golaszewski
2019-10-08 23:21 ` Kent Gibson
2019-10-08 23:30 ` Bartosz Golaszewski
2019-10-08 23:56 ` Kent Gibson
2019-10-09 0:03 ` Bartosz Golaszewski
2019-10-09 0:22 ` Kent Gibson
2019-10-09 6:55 ` Kent Gibson
2019-10-09 12:57 ` Drew Fustini
2019-10-09 13:23 ` Kent Gibson
2019-10-09 13:30 ` Drew Fustini
2019-10-09 14:11 ` Kent Gibson
2019-10-09 15:50 ` Bartosz Golaszewski
2019-10-09 16:19 ` Kent Gibson
2019-10-09 23:59 ` Kent Gibson
2019-10-10 7:47 ` Drew Fustini
2019-10-10 10:14 ` Kent Gibson
2019-10-10 11:17 ` Kent Gibson
2019-10-11 13:04 ` Drew Fustini
2019-10-11 13:06 ` Drew Fustini
2019-10-11 13:49 ` Kent Gibson
2019-10-09 11:32 ` Drew Fustini [this message]
2019-10-09 13:57 ` Drew Fustini
2019-10-09 14:01 ` Kent Gibson
2019-10-09 11:46 ` Drew Fustini
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