Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a18afce5 authored by Ed Blake's avatar Ed Blake Committed by Thierry Reding
Browse files

pwm: img: Add suspend / resume handling 



The power may be disabled during suspend, so implement suspend and
resume callbacks to save and restore register state.

Signed-off-by: default avatarEd Blake <ed.blake@sondrel.com>
[thierry.reding@gmail.com: guard using PM_SLEEP instead of PM]
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 2bd6bf03

drivers/pwm/pwm-img.c

+65 −1
Original line number Diff line number Diff line
@@ -52,6 +52,8 @@ 
 */

#define MIN_TMBASE_STEPS			16



#define IMG_PWM_NPWM				4



struct img_pwm_soc_data {

	u32 max_timebase;

};
@@ -66,6 +68,8 @@ struct img_pwm_chip { 
	int		max_period_ns;

	int		min_period_ns;

	const struct img_pwm_soc_data   *data;

	u32		suspend_ctrl_cfg;

	u32		suspend_ch_cfg[IMG_PWM_NPWM];

};



static inline struct img_pwm_chip *to_img_pwm_chip(struct pwm_chip *chip)
@@ -255,7 +259,7 @@ static int img_pwm_probe(struct platform_device *pdev) 
	pwm->chip.dev = &pdev->dev;

	pwm->chip.ops = &img_pwm_ops;

	pwm->chip.base = -1;

	pwm->chip.npwm = 4;

	pwm->chip.npwm = IMG_PWM_NPWM;



	ret = pwmchip_add(&pwm->chip);

	if (ret < 0) {
@@ -291,9 +295,69 @@ static int img_pwm_remove(struct platform_device *pdev) 
	return pwmchip_remove(&pwm_chip->chip);

}



#ifdef CONFIG_PM_SLEEP

static int img_pwm_suspend(struct device *dev)

{

	struct platform_device *pdev = to_platform_device(dev);

	struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev);

	int i;



	for (i = 0; i < pwm_chip->chip.npwm; i++)

		pwm_chip->suspend_ch_cfg[i] = img_pwm_readl(pwm_chip,

							    PWM_CH_CFG(i));



	pwm_chip->suspend_ctrl_cfg = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);



	clk_disable_unprepare(pwm_chip->pwm_clk);

	clk_disable_unprepare(pwm_chip->sys_clk);



	return 0;

}



static int img_pwm_resume(struct device *dev)

{

	struct platform_device *pdev = to_platform_device(dev);

	struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev);

	int ret;

	int i;



	ret = clk_prepare_enable(pwm_chip->sys_clk);

	if (ret < 0) {

		dev_err(&pdev->dev, "could not prepare or enable sys clock\n");

		return ret;

	}



	ret = clk_prepare_enable(pwm_chip->pwm_clk);

	if (ret < 0) {

		dev_err(&pdev->dev, "could not prepare or enable pwm clock\n");

		clk_disable_unprepare(pwm_chip->sys_clk);

		return ret;

	}



	for (i = 0; i < pwm_chip->chip.npwm; i++)

		img_pwm_writel(pwm_chip, PWM_CH_CFG(i),

			       pwm_chip->suspend_ch_cfg[i]);



	img_pwm_writel(pwm_chip, PWM_CTRL_CFG, pwm_chip->suspend_ctrl_cfg);



	for (i = 0; i < pwm_chip->chip.npwm; i++)

		if (pwm_chip->suspend_ctrl_cfg & BIT(i))

			regmap_update_bits(pwm_chip->periph_regs,

					   PERIP_PWM_PDM_CONTROL,

					   PERIP_PWM_PDM_CONTROL_CH_MASK <<

					   PERIP_PWM_PDM_CONTROL_CH_SHIFT(i),

					   0);



	return 0;

}

#endif /* CONFIG_PM */



SIMPLE_DEV_PM_OPS(img_pwm_pm_ops, img_pwm_suspend, img_pwm_resume);



static struct platform_driver img_pwm_driver = {

	.driver = {

		.name = "img-pwm",

		.pm = &img_pwm_pm_ops,

		.of_match_table = img_pwm_of_match,

	},

	.probe = img_pwm_probe,