Commit 3f2b1673 authored by Jitao Shi's avatar Jitao Shi Committed by Thierry Reding
Browse files

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



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

Signed-off-by: default avatarJitao Shi <jitao.shi@mediatek.com>
[thierry.reding@gmail.com: add missing linux/bitfield.h include]
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 331e049d

drivers/pwm/pwm-mtk-disp.c

+43 −0
Original line number Diff line number Diff line
@@ -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,

};