Patch "clk: qcom: clk-rcg2: Fail Duty-Cycle configuration if MND divider is not enabled." has been added to the 5.18-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    clk: qcom: clk-rcg2: Fail Duty-Cycle configuration if MND divider is not enabled.

to the 5.18-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-rcg2-fail-duty-cycle-configuration-if-m.patch
and it can be found in the queue-5.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 185f9e43fe800d858209c6b764607c72e014fd09
Author: Nikita Travkin <nikita@xxxxxxx>
Date:   Sun Jun 12 19:59:52 2022 +0500

    clk: qcom: clk-rcg2: Fail Duty-Cycle configuration if MND divider is not enabled.
    
    [ Upstream commit bdafb609c3bb848d710ad9cd4debd2ee9d6a4049 ]
    
    In cases when MND is not enabled (e.g. when only Half Integer Divider is
    used), setting D registers makes no effect.
    
    Fail instead of making ineffective write.
    
    Fixes: 7f891faf596e ("clk: qcom: clk-rcg2: Add support for duty-cycle for RCG")
    Signed-off-by: Nikita Travkin <nikita@xxxxxxx>
    Reviewed-by: Stephen Boyd <sboyd@xxxxxxxxxx>
    Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20220612145955.385787-2-nikita@xxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/clk/qcom/clk-rcg2.c b/drivers/clk/qcom/clk-rcg2.c
index e9c357309fd9..9611c9a7231f 100644
--- a/drivers/clk/qcom/clk-rcg2.c
+++ b/drivers/clk/qcom/clk-rcg2.c
@@ -405,7 +405,7 @@ static int clk_rcg2_get_duty_cycle(struct clk_hw *hw, struct clk_duty *duty)
 static int clk_rcg2_set_duty_cycle(struct clk_hw *hw, struct clk_duty *duty)
 {
 	struct clk_rcg2 *rcg = to_clk_rcg2(hw);
-	u32 notn_m, n, m, d, not2d, mask, duty_per;
+	u32 notn_m, n, m, d, not2d, mask, duty_per, cfg;
 	int ret;
 
 	/* Duty-cycle cannot be modified for non-MND RCGs */
@@ -416,6 +416,11 @@ static int clk_rcg2_set_duty_cycle(struct clk_hw *hw, struct clk_duty *duty)
 
 	regmap_read(rcg->clkr.regmap, RCG_N_OFFSET(rcg), &notn_m);
 	regmap_read(rcg->clkr.regmap, RCG_M_OFFSET(rcg), &m);
+	regmap_read(rcg->clkr.regmap, RCG_CFG_OFFSET(rcg), &cfg);
+
+	/* Duty-cycle cannot be modified if MND divider is in bypass mode. */
+	if (!(cfg & CFG_MODE_MASK))
+		return -EINVAL;
 
 	n = (~(notn_m) + m) & mask;