[2/2] gpiolib: do not allow to insert an empty gpiochip
diff mbox

Message ID 1447490336-10209-3-git-send-email-bamvor.zhangjian@linaro.org
State New
Headers show

Commit Message

Bamvor Jian Zhang Nov. 14, 2015, 8:38 a.m. UTC
We need to check if number of gpio is positive if there is no
such check in devicetree or acpi or whatever called before
gpiochip_add.

I suppose that devicetree and acpi do not allow insert gpiochip
with zero number but I do not know if it is enough to ignore
this check in gpiochip_add.

Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
---
 drivers/gpio/gpiolib.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Linus Walleij Nov. 14, 2015, 11:03 a.m. UTC | #1
On Sat, Nov 14, 2015 at 9:38 AM, Bamvor Jian Zhang
<bamvor.zhangjian@linaro.org> wrote:

> We need to check if number of gpio is positive if there is no
> such check in devicetree or acpi or whatever called before
> gpiochip_add.
>
> I suppose that devicetree and acpi do not allow insert gpiochip
> with zero number but I do not know if it is enough to ignore
> this check in gpiochip_add.
>
> Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>

> +       if (chip->ngpio == 0)
> +               return -EINVAL;

Print a warning with chip_err(chip, "tried to insert a GPIO chip with
zero lines\n");

Yours,
Linus Walleij
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Patch
diff mbox

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index cc135d9..868ff15 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -327,6 +327,9 @@  int gpiochip_add(struct gpio_chip *chip)
 	if (!descs)
 		return -ENOMEM;
 
+	if (chip->ngpio == 0)
+		return -EINVAL;
+
 	spin_lock_irqsave(&gpio_lock, flags);
 
 	if (base < 0) {