Re: [PATCH -next] backlight: qcom-wled: fix unsigned comparison to zero

From: Bjorn Andersson
Date: Tue Jan 21 2020 - 19:39:38 EST


On Mon 20 Jan 05:01 PST 2020, Chen Zhou wrote:

> Fixes coccicheck warning:
> ./drivers/video/backlight/qcom-wled.c:1104:5-15:
> WARNING: Unsigned expression compared with zero: string_len > 0
>
> The unsigned variable string_len is assigned a return value from the call
> to wled_configure, which may return negative error code.
>

Afaict string_len is the return value of
of_property_count_elems_of_size(), rather than wled_configure(). (And
please append () to function names to make it even more obvious)

Except for that your patch looks good, so please update the commit
message and add my Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Regards,
Bjorn

> Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3")
> Signed-off-by: Chen Zhou <chenzhou10@xxxxxxxxxx>
> ---
> drivers/video/backlight/qcom-wled.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
> index d46052d..3d276b3 100644
> --- a/drivers/video/backlight/qcom-wled.c
> +++ b/drivers/video/backlight/qcom-wled.c
> @@ -956,8 +956,8 @@ static int wled_configure(struct wled *wled, int version)
> struct wled_config *cfg = &wled->cfg;
> struct device *dev = wled->dev;
> const __be32 *prop_addr;
> - u32 size, val, c, string_len;
> - int rc, i, j;
> + u32 size, val, c;
> + int rc, i, j, string_len;
>
> const struct wled_u32_opts *u32_opts = NULL;
> const struct wled_u32_opts wled3_opts[] = {
> --
> 2.7.4
>