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pwm: mtk-disp: Implement atomic API .get_state()

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Switch the driver to support the .get_state() method.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
[thierry.reding@gmail.com: add missing linux/bitfield.h include]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Jitao Shi 2021-08-08 21:24:33 +08:00 committed by Thierry Reding
parent 331e049dec
commit 3f2b167349
1 changed files with 43 additions and 0 deletions
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43
drivers/pwm/pwm-mtk-disp.c
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@ -5,6 +5,7 @@
* Author: YH Huang <yh.huang@mediatek.com>
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
@ -171,8 +172,50 @@ static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
return 0;
}
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);
u64 rate, period, high_width;
u32 clk_div, con0, con1;
int err;
err = clk_prepare_enable(mdp->clk_main);
if (err < 0) {
dev_err(chip->dev, "Can't enable mdp->clk_main: %pe\n", ERR_PTR(err));
return;
}
err = clk_prepare_enable(mdp->clk_mm);
if (err < 0) {
dev_err(chip->dev, "Can't enable mdp->clk_mm: %pe\n", ERR_PTR(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->enabled = !!(con0 & BIT(0));
clk_div = FIELD_GET(PWM_CLKDIV_MASK, con0);
period = FIELD_GET(PWM_PERIOD_MASK, con1);
/*
* period has 12 bits, clk_div 11 and NSEC_PER_SEC has 30,
* so period * (clk_div + 1) * NSEC_PER_SEC doesn't overflow.
*/
state->period = DIV64_U64_ROUND_UP(period * (clk_div + 1) * NSEC_PER_SEC, rate);
high_width = FIELD_GET(PWM_HIGH_WIDTH_MASK, con1);
state->duty_cycle = DIV64_U64_ROUND_UP(high_width * (clk_div + 1) * NSEC_PER_SEC,
rate);
state->polarity = PWM_POLARITY_NORMAL;
clk_disable_unprepare(mdp->clk_mm);
clk_disable_unprepare(mdp->clk_main);
}
static const struct pwm_ops mtk_disp_pwm_ops = {
.apply = mtk_disp_pwm_apply,
.get_state = mtk_disp_pwm_get_state,
.owner = THIS_MODULE,
};