clk: tegra: Fix refcounting of gate clocks
stable inclusion from stable-5.10.51 commit dc5bacea9462cf8e17340eb666e6c4d4b9a1e4bd bugzilla: 175263 https://gitee.com/openeuler/kernel/issues/I4DT6F Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dc5bacea9462cf8e17340eb666e6c4d4b9a1e4bd -------------------------------- [ Upstream commit c592c8a2 ] The refcounting of the gate clocks has a bug causing the enable_refcnt to underflow when unused clocks are disabled. This happens because clk provider erroneously bumps the refcount if clock is enabled at a boot time, which it shouldn't be doing, and it does this only for the gate clocks, while peripheral clocks are using the same gate ops and the peripheral clocks are missing the initial bump. Hence the refcount of the peripheral clocks is 0 when unused clocks are disabled and then the counter is decremented further by the gate ops, causing the integer underflow. Fix this problem by removing the erroneous bump and by implementing the disable_unused() callback, which disables the unused gates properly. The visible effect of the bug is such that the unused clocks are never gated if a loaded kernel module grabs the unused clocks and starts to use them. In practice this shouldn't cause any real problems for the drivers and boards supported by the kernel today. Acked-by:Thierry Reding <treding@nvidia.com> Signed-off-by:
Dmitry Osipenko <digetx@gmail.com> Signed-off-by:
Thierry Reding <treding@nvidia.com> Signed-off-by:
Sasha Levin <sashal@kernel.org> Signed-off-by:
Chen Jun <chenjun102@huawei.com> Acked-by:
Weilong Chen <chenweilong@huawei.com> Signed-off-by:
Chen Jun <chenjun102@huawei.com> Signed-off-by:
Zheng Zengkai <zhengzengkai@huawei.com>
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