This is a note to let you know that I've just added the patch titled clk: qcom: clk-krait: unlock spin after mux completion to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: clk-qcom-clk-krait-unlock-spin-after-mux-completion.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit fae0a51d8d1782d4468473fd8cdb046e6533fd99 Author: Christian Marangi <ansuelsmth@xxxxxxxxx> Date: Sat Apr 30 07:44:57 2022 +0200 clk: qcom: clk-krait: unlock spin after mux completion [ Upstream commit df83d2c9e72910416f650ade1e07cc314ff02731 ] Unlock spinlock after the mux switch is completed to prevent any corner case of mux request while the switch still needs to be done. Fixes: 4d7dc77babfe ("clk: qcom: Add support for Krait clocks") Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220430054458.31321-3-ansuelsmth@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/clk/qcom/clk-krait.c b/drivers/clk/qcom/clk-krait.c index 59f1af415b58..90046428693c 100644 --- a/drivers/clk/qcom/clk-krait.c +++ b/drivers/clk/qcom/clk-krait.c @@ -32,11 +32,16 @@ static void __krait_mux_set_sel(struct krait_mux_clk *mux, int sel) regval |= (sel & mux->mask) << (mux->shift + LPL_SHIFT); } krait_set_l2_indirect_reg(mux->offset, regval); - spin_unlock_irqrestore(&krait_clock_reg_lock, flags); /* Wait for switch to complete. */ mb(); udelay(1); + + /* + * Unlock now to make sure the mux register is not + * modified while switching to the new parent. + */ + spin_unlock_irqrestore(&krait_clock_reg_lock, flags); } static int krait_mux_set_parent(struct clk_hw *hw, u8 index)