[PATCH v2 3/3] pwm: mtk_disp: implement .get_state()

[Jitao Shi]

Signed-off-by: Jitao Shi <jitao....@mediatek.com>
---
 drivers/pwm/pwm-mtk-disp.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
index 502228adf718..166e0a8ca703 100644
--- a/drivers/pwm/pwm-mtk-disp.c
+++ b/drivers/pwm/pwm-mtk-disp.c
@@ -179,8 +179,54 @@ static int mtk_disp_pwm_apply(struct pwm_chip *chip, 
struct pwm_device *pwm,
        return mtk_disp_pwm_enable(chip, state);
 }
 
+static void mtk_disp_pwm_get_state(struct pwm_chip *chip,
+                                  struct pwm_device *pwm,
+                                  struct pwm_state *state)
+{
+       struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
+       u32 clk_div, period, high_width, con0, con1;
+       u64 rate;
+       int err;
+
+       err = clk_prepare_enable(mdp->clk_main);
+       if (err < 0) {
+               dev_err(chip->dev, "Can't enable mdp->clk_main: %d\n", err);
+               return;
+       }
+       err = clk_prepare_enable(mdp->clk_mm);
+       if (err < 0) {
+               dev_err(chip->dev, "Can't enable mdp->clk_mm: %d\n", err);
+               clk_disable_unprepare(mdp->clk_main);
+               return;
+       }
+
+       rate = clk_get_rate(mdp->clk_main);
+
+       con0 = readl(mdp->base + mdp->data->con0);
+       con1 = readl(mdp->base + mdp->data->con1);
+
+       state->polarity = con0 & PWM_POLARITY ?
+                         PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL;
+       state->enabled = !!(con0 & BIT(0));
+
+       clk_div = (con0 & PWM_CLKDIV_MASK) >> PWM_CLKDIV_SHIFT;
+       period = con1 & PWM_PERIOD_MASK;
+       state->period = div_u64(period * (clk_div + 1) * NSEC_PER_SEC, rate);
+       high_width = (con1 & PWM_HIGH_WIDTH_MASK) >> PWM_HIGH_WIDTH_SHIFT;
+       state->duty_cycle = div_u64(high_width * (clk_div + 1) * NSEC_PER_SEC,
+                                   rate);
+
+       if (!state->enabled) {
+               clk_disable_unprepare(mdp->clk_mm);
+               clk_disable_unprepare(mdp->clk_main);
+       }
+
+       mdp->enabled = state->enabled;
+}
+
 static const struct pwm_ops mtk_disp_pwm_ops = {
        .apply = mtk_disp_pwm_apply,
+       .get_state = mtk_disp_pwm_get_state,
        .owner = THIS_MODULE,
 };
 
-- 
2.12.5