Commit bad81383 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

sh: CMT: Basic runtime PM support 



Modify the SH CMT clock source/clock event device driver to support
runtime PM at a basic level (i.e. device clocks can be disabled and
enabled, but domain power must be on, because the devices have to
be marked as "irq safe").

Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Acked-by: default avatarMagnus Damm <damm@opensource.se>
parent 61a53bfa

drivers/clocksource/sh_cmt.c

+36 −8
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 
#include <linux/slab.h>

#include <linux/module.h>

#include <linux/pm_domain.h>

#include <linux/pm_runtime.h>



struct sh_cmt_priv {

	void __iomem *mapbase;
@@ -52,6 +53,7 @@ struct sh_cmt_priv { 
	struct clock_event_device ced;

	struct clocksource cs;

	unsigned long total_cycles;

	bool cs_enabled;

};



static DEFINE_RAW_SPINLOCK(sh_cmt_lock);
@@ -155,6 +157,9 @@ static int sh_cmt_enable(struct sh_cmt_priv *p, unsigned long *rate) 
{

	int k, ret;



	pm_runtime_get_sync(&p->pdev->dev);

	dev_pm_syscore_device(&p->pdev->dev, true);



	/* enable clock */

	ret = clk_enable(p->clk);

	if (ret) {
@@ -221,6 +226,9 @@ static void sh_cmt_disable(struct sh_cmt_priv *p) 


	/* stop clock */

	clk_disable(p->clk);



	dev_pm_syscore_device(&p->pdev->dev, false);

	pm_runtime_put(&p->pdev->dev);

}



/* private flags */
@@ -451,17 +459,26 @@ static int sh_cmt_clocksource_enable(struct clocksource *cs) 
	int ret;

	struct sh_cmt_priv *p = cs_to_sh_cmt(cs);



	WARN_ON(p->cs_enabled);



	p->total_cycles = 0;



	ret = sh_cmt_start(p, FLAG_CLOCKSOURCE);

	if (!ret)

	if (!ret) {

		__clocksource_updatefreq_hz(cs, p->rate);

		p->cs_enabled = true;

	}

	return ret;

}



static void sh_cmt_clocksource_disable(struct clocksource *cs)

{

	sh_cmt_stop(cs_to_sh_cmt(cs), FLAG_CLOCKSOURCE);

	struct sh_cmt_priv *p = cs_to_sh_cmt(cs);



	WARN_ON(!p->cs_enabled);



	sh_cmt_stop(p, FLAG_CLOCKSOURCE);

	p->cs_enabled = false;

}



static void sh_cmt_clocksource_suspend(struct clocksource *cs)
@@ -693,6 +710,7 @@ static int sh_cmt_setup(struct sh_cmt_priv *p, struct platform_device *pdev) 
		dev_err(&p->pdev->dev, "registration failed\n");

		goto err1;

	}

	p->cs_enabled = false;



	ret = setup_irq(irq, &p->irqaction);

	if (ret) {
@@ -711,18 +729,17 @@ err0: 
static int __devinit sh_cmt_probe(struct platform_device *pdev)

{

	struct sh_cmt_priv *p = platform_get_drvdata(pdev);

	struct sh_timer_config *cfg = pdev->dev.platform_data;

	int ret;



	if (!is_early_platform_device(pdev)) {

		struct sh_timer_config *cfg = pdev->dev.platform_data;



		if (cfg->clocksource_rating || cfg->clockevent_rating)

			dev_pm_syscore_device(&pdev->dev, true);

		pm_runtime_set_active(&pdev->dev);

		pm_runtime_enable(&pdev->dev);

	}



	if (p) {

		dev_info(&pdev->dev, "kept as earlytimer\n");

		return 0;

		goto out;

	}



	p = kmalloc(sizeof(*p), GFP_KERNEL);
@@ -735,9 +752,20 @@ static int __devinit sh_cmt_probe(struct platform_device *pdev) 
	if (ret) {

		kfree(p);

		platform_set_drvdata(pdev, NULL);

	}

		pm_runtime_idle(&pdev->dev);

		return ret;

	}

	if (is_early_platform_device(pdev))

		return 0;



 out:

	if (cfg->clockevent_rating || cfg->clocksource_rating)

		pm_runtime_irq_safe(&pdev->dev);

	else

		pm_runtime_idle(&pdev->dev);



	return 0;

}



static int __devexit sh_cmt_remove(struct platform_device *pdev)

{

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