media: qcom: camss: Fix VFE-17x vfe_disable_output()
stable inclusion from stable-v6.6.3 commit b1eaec007b6038e729402dba9276d2413c701dba category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8LBQP Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b1eaec007b6038e729402dba9276d2413c701dba -------------------------------- commit 3143ad282fc08bf995ee73e32a9e40c527bf265d upstream. There are two problems with the current vfe_disable_output() routine. Firstly we rightly use a spinlock to protect output->gen2.active_num everywhere except for in the IDLE timeout path of vfe_disable_output(). Even if that is not racy "in practice" somehow it is by happenstance not by design. Secondly we do not get consistent behaviour from this routine. On sc8280xp 50% of the time I get "VFE idle timeout - resetting". In this case the subsequent capture will succeed. The other 50% of the time, we don't hit the idle timeout, never do the VFE reset and subsequent captures stall indefinitely. Rewrite the vfe_disable_output() routine to - Quiesce write masters with vfe_wm_stop() - Set active_num = 0 remembering to hold the spinlock when we do so followed by - Reset the VFE Testing on sc8280xp and sdm845 shows this to be a valid fix. Fixes: 7319cdf1 ("media: camss: Add support for VFE hardware version Titan 170") Cc: stable@vger.kernel.org Signed-off-by:Bryan O'Donoghue <bryan.odonoghue@linaro.org> Signed-off-by:
Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
Zheng Zengkai <zhengzengkai@huawei.com>
Loading
Please sign in to comment