Commit 08a4d8ec authored by Bartlomiej Zolnierkiewicz's avatar Bartlomiej Zolnierkiewicz Committed by Thierry Reding
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pwm: pwm-samsung: fix suspend/resume support 



Fix suspend/resume support:

- add disabled_mask to struct samsung_pwm_chip to track PWM
  disabled state information in pwm_samsung_{disable,enable}()

- rename pwm_samsung_config() to __pwm_samsung_config() and
  add extra force_period parameter to be used during resume
  (to force tin_ns and tcnt recalculation)

- add pwm_samsung_config() wrapper for preserving old behavior

- properly restore PWM configuration in pwm_samsung_resume()

- remove no longer needed pwm_samsung_suspend()

- update Copyrights

Signed-off-by: default avatarBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 23aa19a2

drivers/pwm/pwm-samsung.c

+35 −32
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
 * Copyright (c) 2008 Simtec Electronics

 *     Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org>

 * Copyright (c) 2013 Tomasz Figa <tomasz.figa@gmail.com>

 * Copyright (c) 2017 Samsung Electronics Co., Ltd.

 *

 * PWM driver for Samsung SoCs

 *
@@ -74,6 +75,7 @@ struct samsung_pwm_channel { 
 * @chip:		generic PWM chip

 * @variant:		local copy of hardware variant data

 * @inverter_mask:	inverter status for all channels - one bit per channel

 * @disabled_mask:	disabled status for all channels - one bit per channel

 * @base:		base address of mapped PWM registers

 * @base_clk:		base clock used to drive the timers

 * @tclk0:		external clock 0 (can be ERR_PTR if not present)
@@ -83,6 +85,7 @@ struct samsung_pwm_chip { 
	struct pwm_chip chip;

	struct samsung_pwm_variant variant;

	u8 inverter_mask;

	u8 disabled_mask;



	void __iomem *base;

	struct clk *base_clk;
@@ -257,6 +260,8 @@ static int pwm_samsung_enable(struct pwm_chip *chip, struct pwm_device *pwm) 
	tcon |= TCON_START(tcon_chan) | TCON_AUTORELOAD(tcon_chan);

	writel(tcon, our_chip->base + REG_TCON);



	our_chip->disabled_mask &= ~BIT(pwm->hwpwm);



	spin_unlock_irqrestore(&samsung_pwm_lock, flags);



	return 0;
@@ -275,6 +280,8 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm) 
	tcon &= ~TCON_AUTORELOAD(tcon_chan);

	writel(tcon, our_chip->base + REG_TCON);



	our_chip->disabled_mask |= BIT(pwm->hwpwm);



	spin_unlock_irqrestore(&samsung_pwm_lock, flags);

}
@@ -297,8 +304,8 @@ static void pwm_samsung_manual_update(struct samsung_pwm_chip *chip, 
	spin_unlock_irqrestore(&samsung_pwm_lock, flags);

}



static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,

			      int duty_ns, int period_ns)

static int __pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,

				int duty_ns, int period_ns, bool force_period)

{

	struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);

	struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
@@ -319,7 +326,7 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm, 
	++tcnt;



	/* Check to see if we are changing the clock rate of the PWM. */

	if (chan->period_ns != period_ns) {

	if (chan->period_ns != period_ns || force_period) {

		unsigned long tin_rate;

		u32 period;
@@ -378,6 +385,12 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm, 
	return 0;

}



static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,

			      int duty_ns, int period_ns)

{

	return __pwm_samsung_config(chip, pwm, duty_ns, period_ns, false);

}



static void pwm_samsung_set_invert(struct samsung_pwm_chip *chip,

				   unsigned int channel, bool invert)

{
@@ -589,51 +602,41 @@ static int pwm_samsung_remove(struct platform_device *pdev) 
}



#ifdef CONFIG_PM_SLEEP

static int pwm_samsung_suspend(struct device *dev)

static int pwm_samsung_resume(struct device *dev)

{

	struct samsung_pwm_chip *chip = dev_get_drvdata(dev);

	struct samsung_pwm_chip *our_chip = dev_get_drvdata(dev);

	struct pwm_chip *chip = &our_chip->chip;

	unsigned int i;



	/*

	 * No one preserves these values during suspend so reset them.

	 * Otherwise driver leaves PWM unconfigured if same values are

	 * passed to pwm_config() next time.

	 */

	for (i = 0; i < SAMSUNG_PWM_NUM; ++i) {

		struct pwm_device *pwm = &chip->chip.pwms[i];

	for (i = 0; i < SAMSUNG_PWM_NUM; i++) {

		struct pwm_device *pwm = &chip->pwms[i];

		struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);



		if (!chan)

			continue;



		chan->period_ns = 0;

		chan->duty_ns = 0;

	}

		if (our_chip->variant.output_mask & BIT(i))

			pwm_samsung_set_invert(our_chip, i,

					our_chip->inverter_mask & BIT(i));



	return 0;

		if (chan->period_ns) {

			__pwm_samsung_config(chip, pwm, chan->duty_ns,

					     chan->period_ns, true);

			/* needed to make PWM disable work on Odroid-XU3 */

			pwm_samsung_manual_update(our_chip, pwm);

		}



static int pwm_samsung_resume(struct device *dev)

{

	struct samsung_pwm_chip *chip = dev_get_drvdata(dev);

	unsigned int chan;



	/*

	 * Inverter setting must be preserved across suspend/resume

	 * as nobody really seems to configure it more than once.

	 */

	for (chan = 0; chan < SAMSUNG_PWM_NUM; ++chan) {

		if (chip->variant.output_mask & BIT(chan))

			pwm_samsung_set_invert(chip, chan,

					chip->inverter_mask & BIT(chan));

		if (our_chip->disabled_mask & BIT(i))

			pwm_samsung_disable(chip, pwm);

		else

			pwm_samsung_enable(chip, pwm);

	}



	return 0;

}

#endif



static SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, pwm_samsung_suspend,

			 pwm_samsung_resume);

static SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, NULL, pwm_samsung_resume);



static struct platform_driver pwm_samsung_driver = {

	.driver		= {

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