diff options
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-ctrls.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c index 1acc7aa9d7e2..004e7e82e1e0 100644 --- a/drivers/media/v4l2-core/v4l2-ctrls.c +++ b/drivers/media/v4l2-core/v4l2-ctrls.c @@ -1295,11 +1295,19 @@ static void std_log(const struct v4l2_ctrl *ctrl) } } -/* Round towards the closest legal value */ +/* + * Round towards the closest legal value. Be careful when we are + * close to the maximum range of the control type to prevent + * wrap-arounds. + */ #define ROUND_TO_RANGE(val, offset_type, ctrl) \ ({ \ offset_type offset; \ - val += (ctrl)->step / 2; \ + if ((ctrl)->maximum >= 0 && \ + val >= (ctrl)->maximum - ((ctrl)->step / 2)) \ + val = (ctrl)->maximum; \ + else \ + val += (ctrl)->step / 2; \ val = clamp_t(typeof(val), val, \ (ctrl)->minimum, (ctrl)->maximum); \ offset = (val) - (ctrl)->minimum; \ @@ -1325,7 +1333,10 @@ static int std_validate(const struct v4l2_ctrl *ctrl, u32 idx, * the u64 divide that needs special care. */ val = ptr.p_s64[idx]; - val += ctrl->step / 2; + if (ctrl->maximum >= 0 && val >= ctrl->maximum - ctrl->step / 2) + val = ctrl->maximum; + else + val += ctrl->step / 2; val = clamp_t(s64, val, ctrl->minimum, ctrl->maximum); offset = val - ctrl->minimum; do_div(offset, ctrl->step); |