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Subject[PATCH v2 2/3] pwm: mtk_disp: convert the driver to atomic API
Date
Switch the driver to atomic API apply().

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
---
drivers/pwm/pwm-mtk-disp.c | 114 +++++++++++++++++++++++----------------------
1 file changed, 58 insertions(+), 56 deletions(-)

diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c
index 21416a8b6b47..502228adf718 100644
--- a/drivers/pwm/pwm-mtk-disp.c
+++ b/drivers/pwm/pwm-mtk-disp.c
@@ -20,6 +20,7 @@
#define PWM_CLKDIV_SHIFT 16
#define PWM_CLKDIV_MAX 0x3ff
#define PWM_CLKDIV_MASK (PWM_CLKDIV_MAX << PWM_CLKDIV_SHIFT)
+#define PWM_POLARITY BIT(2)

#define PWM_PERIOD_BIT_WIDTH 12
#define PWM_PERIOD_MASK ((1 << PWM_PERIOD_BIT_WIDTH) - 1)
@@ -47,6 +48,7 @@ struct mtk_disp_pwm {
struct clk *clk_main;
struct clk *clk_mm;
void __iomem *base;
+ bool enabled;
};

static inline struct mtk_disp_pwm *to_mtk_disp_pwm(struct pwm_chip *chip)
@@ -66,11 +68,11 @@ static void mtk_disp_pwm_update_bits(struct mtk_disp_pwm *mdp, u32 offset,
writel(value, address);
}

-static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
- int duty_ns, int period_ns)
+static int mtk_disp_pwm_enable(struct pwm_chip *chip,
+ const struct pwm_state *state)
{
struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
- u32 clk_div, period, high_width, value;
+ u32 clk_div, period, high_width, value, polarity;
u64 div, rate;
int err;

@@ -84,33 +86,47 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
* period = (PWM_CLK_RATE * period_ns) / (10^9 * (clk_div + 1)) - 1
* high_width = (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1))
*/
+ if (!mdp->enabled) {
+ 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;
+ }
+ 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 err;
+ }
+ }
rate = clk_get_rate(mdp->clk_main);
- clk_div = div_u64(rate * period_ns, NSEC_PER_SEC) >>
+ clk_div = div_u64(rate * state->period, NSEC_PER_SEC) >>
PWM_PERIOD_BIT_WIDTH;
- if (clk_div > PWM_CLKDIV_MAX)
+ if (clk_div > PWM_CLKDIV_MAX) {
+ dev_err(chip->dev, "clock rate is too high: rate = %d Hz\n",
+ rate);
+ clk_disable_unprepare(mdp->clk_mm);
+ clk_disable_unprepare(mdp->clk_main);
return -EINVAL;
-
+ }
div = NSEC_PER_SEC * (clk_div + 1);
- period = div64_u64(rate * period_ns, div);
+ period = div64_u64(rate * state->period, div);
if (period > 0)
period--;

- high_width = div64_u64(rate * duty_ns, div);
+ high_width = div64_u64(rate * state->duty_cycle, div);
value = period | (high_width << PWM_HIGH_WIDTH_SHIFT);
-
- err = clk_enable(mdp->clk_main);
- if (err < 0)
- return err;
-
- err = clk_enable(mdp->clk_mm);
- if (err < 0) {
- clk_disable(mdp->clk_main);
- return err;
- }
+ polarity = 0;
+ if (state->polarity == PWM_POLARITY_INVERSED)
+ polarity = PWM_POLARITY;

mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
PWM_CLKDIV_MASK,
clk_div << PWM_CLKDIV_SHIFT);
+ mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
+ PWM_POLARITY, polarity);
mtk_disp_pwm_update_bits(mdp, mdp->data->con1,
PWM_PERIOD_MASK | PWM_HIGH_WIDTH_MASK,
value);
@@ -122,50 +138,49 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
mtk_disp_pwm_update_bits(mdp, mdp->data->commit,
mdp->data->commit_mask,
0x0);
+ } else {
+ mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug,
+ mdp->data->bls_debug_mask,
+ mdp->data->bls_debug_mask);
+ mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
+ mdp->data->con0_sel,
+ mdp->data->con0_sel);
}

- clk_disable(mdp->clk_mm);
- clk_disable(mdp->clk_main);
-
+ mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
+ mdp->data->enable_mask);
+ mdp->enabled = true;
return 0;
}

-static int mtk_disp_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+static int mtk_disp_pwm_disable(struct pwm_chip *chip,
+ const struct pwm_state *state)
{
struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
- int err;
-
- err = clk_enable(mdp->clk_main);
- if (err < 0)
- return err;

- err = clk_enable(mdp->clk_mm);
- if (err < 0) {
- clk_disable(mdp->clk_main);
- return err;
+ mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
+ 0x0);
+ if (mdp->enabled) {
+ clk_disable_unprepare(mdp->clk_mm);
+ clk_disable_unprepare(mdp->clk_main);
}

- mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
- mdp->data->enable_mask);
+ mdp->enabled = false;

return 0;
}

-static void mtk_disp_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
{
- struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip);
+ if (!state->enabled)
+ return mtk_disp_pwm_disable(chip, state);

- mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask,
- 0x0);
-
- clk_disable(mdp->clk_mm);
- clk_disable(mdp->clk_main);
+ return mtk_disp_pwm_enable(chip, state);
}

static const struct pwm_ops mtk_disp_pwm_ops = {
- .config = mtk_disp_pwm_config,
- .enable = mtk_disp_pwm_enable,
- .disable = mtk_disp_pwm_disable,
+ .apply = mtk_disp_pwm_apply,
.owner = THIS_MODULE,
};

@@ -205,19 +220,6 @@ static int mtk_disp_pwm_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, mdp);

- /*
- * For MT2701, disable double buffer before writing register
- * and select manual mode and use PWM_PERIOD/PWM_HIGH_WIDTH.
- */
- if (!mdp->data->has_commit) {
- mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug,
- mdp->data->bls_debug_mask,
- mdp->data->bls_debug_mask);
- mtk_disp_pwm_update_bits(mdp, mdp->data->con0,
- mdp->data->con0_sel,
- mdp->data->con0_sel);
- }
-
return 0;
}

--
2.12.5
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