Re: [PATCH] media: tc358743: initialize variable

From: Nick Desaulniers
Date: Mon Aug 31 2020 - 13:32:24 EST


On Sun, Aug 30, 2020 at 9:30 AM <trix@xxxxxxxxxx> wrote:
>
> From: Tom Rix <trix@xxxxxxxxxx>
>
> clang static analysis flags this error
>
> tc358743.c:1468:9: warning: Branch condition evaluates
> to a garbage value
> return handled ? IRQ_HANDLED : IRQ_NONE;
> ^~~~~~~
> handled should be initialized to false.
>
> Fixes: d747b806abf4 ("[media] tc358743: add direct interrupt handling")
> Signed-off-by: Tom Rix <trix@xxxxxxxxxx>

I'm guessing there was more to the report that says that `handled`
isn't necessarily initialized along any of the paths within
tc358743_isr()? But you should fix this for all callers of
tc358743_isr(), such as tc358743_work_i2c_poll(), not just
tc358743_irq_handler().

> ---
> drivers/media/i2c/tc358743.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/i2c/tc358743.c b/drivers/media/i2c/tc358743.c
> index a03dcab5ce61..c724bd1591de 100644
> --- a/drivers/media/i2c/tc358743.c
> +++ b/drivers/media/i2c/tc358743.c
> @@ -1461,7 +1461,7 @@ static int tc358743_isr(struct v4l2_subdev *sd, u32 status, bool *handled)
> static irqreturn_t tc358743_irq_handler(int irq, void *dev_id)
> {
> struct tc358743_state *state = dev_id;
> - bool handled;
> + bool handled = false;
>
> tc358743_isr(&state->sd, 0, &handled);
>
> --
> 2.18.1
>


--
Thanks,
~Nick Desaulniers