From: Nikita Travkin nikita@trvn.ru
[ 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@trvn.ru Reviewed-by: Stephen Boyd sboyd@kernel.org Signed-off-by: Bjorn Andersson bjorn.andersson@linaro.org Link: https://lore.kernel.org/r/20220612145955.385787-2-nikita@trvn.ru Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/clk/qcom/clk-rcg2.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/qcom/clk-rcg2.c b/drivers/clk/qcom/clk-rcg2.c index 8e5dce09d162..2375e8122012 100644 --- a/drivers/clk/qcom/clk-rcg2.c +++ b/drivers/clk/qcom/clk-rcg2.c @@ -437,7 +437,7 @@ 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 */ @@ -448,6 +448,11 @@ static int clk_rcg2_set_duty_cycle(struct clk_hw *hw, struct clk_duty *duty)
regmap_read(rcg->clkr.regmap, RCG_N_OFFSET(rcg), ¬n_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;