Re: [PATCH v5 34/46] clk: pwm: switch to the atomic API
From: Stephen Boyd <hidden>
Date: 2016-03-30 22:01:56
Also in:
dri-devel, intel-gfx, linux-arm-kernel, linux-clk, linux-input, linux-leds, linux-pwm, linux-rockchip, linux-samsung-soc, lkml
On 03/30, Boris Brezillon wrote:
quoted hunk ↗ jump to hunk
diff --git a/drivers/clk/clk-pwm.c b/drivers/clk/clk-pwm.c index ebcd738..49ec5b1 100644 --- a/drivers/clk/clk-pwm.c +++ b/drivers/clk/clk-pwm.c@@ -28,15 +28,29 @@ static inline struct clk_pwm *to_clk_pwm(struct clk_hw *hw) static int clk_pwm_prepare(struct clk_hw *hw) { struct clk_pwm *clk_pwm = to_clk_pwm(hw); + struct pwm_state pstate; - return pwm_enable(clk_pwm->pwm); + pwm_get_state(clk_pwm->pwm, &pstate); + if (pstate.enabled) + return 0; + + pstate.enabled = true; + + return pwm_apply_state(clk_pwm->pwm, &pstate);
This doesn't seem atomic anymore if we're checking the state and then not calling apply_state if it's already enabled. But I assume this doesn't matter because we "own" the pwm here? Otherwise I would think this would be unconditional apply state and duplicates would be ignored in the pwm framework. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project