From 61a53bfaa11644b8e9850ac79024b06465a43518 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 6 Aug 2012 01:48:17 +0200 Subject: sh: TMU: Basic runtime PM support Modify the SH TMU 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: Rafael J. Wysocki Acked-by: Magnus Damm --- drivers/clocksource/sh_tmu.c | 80 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 65 insertions(+), 15 deletions(-) (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/sh_tmu.c b/drivers/clocksource/sh_tmu.c index 81b0239718ee..0cc4add88279 100644 --- a/drivers/clocksource/sh_tmu.c +++ b/drivers/clocksource/sh_tmu.c @@ -45,6 +45,7 @@ struct sh_tmu_priv { struct clock_event_device ced; struct clocksource cs; bool cs_enabled; + unsigned int enable_count; }; static DEFINE_RAW_SPINLOCK(sh_tmu_lock); @@ -109,7 +110,7 @@ static void sh_tmu_start_stop_ch(struct sh_tmu_priv *p, int start) raw_spin_unlock_irqrestore(&sh_tmu_lock, flags); } -static int sh_tmu_enable(struct sh_tmu_priv *p) +static int __sh_tmu_enable(struct sh_tmu_priv *p) { int ret; @@ -137,7 +138,18 @@ static int sh_tmu_enable(struct sh_tmu_priv *p) return 0; } -static void sh_tmu_disable(struct sh_tmu_priv *p) +static int sh_tmu_enable(struct sh_tmu_priv *p) +{ + if (p->enable_count++ > 0) + return 0; + + pm_runtime_get_sync(&p->pdev->dev); + dev_pm_syscore_device(&p->pdev->dev, true); + + return __sh_tmu_enable(p); +} + +static void __sh_tmu_disable(struct sh_tmu_priv *p) { /* disable channel */ sh_tmu_start_stop_ch(p, 0); @@ -149,6 +161,20 @@ static void sh_tmu_disable(struct sh_tmu_priv *p) clk_disable(p->clk); } +static void sh_tmu_disable(struct sh_tmu_priv *p) +{ + if (WARN_ON(p->enable_count == 0)) + return; + + if (--p->enable_count > 0) + return; + + __sh_tmu_disable(p); + + dev_pm_syscore_device(&p->pdev->dev, false); + pm_runtime_put(&p->pdev->dev); +} + static void sh_tmu_set_next(struct sh_tmu_priv *p, unsigned long delta, int periodic) { @@ -205,11 +231,15 @@ static int sh_tmu_clocksource_enable(struct clocksource *cs) struct sh_tmu_priv *p = cs_to_sh_tmu(cs); int ret; + if (WARN_ON(p->cs_enabled)) + return 0; + ret = sh_tmu_enable(p); if (!ret) { __clocksource_updatefreq_hz(cs, p->rate); p->cs_enabled = true; } + return ret; } @@ -217,7 +247,8 @@ static void sh_tmu_clocksource_disable(struct clocksource *cs) { struct sh_tmu_priv *p = cs_to_sh_tmu(cs); - WARN_ON(!p->cs_enabled); + if (WARN_ON(!p->cs_enabled)) + return; sh_tmu_disable(p); p->cs_enabled = false; @@ -227,19 +258,26 @@ static void sh_tmu_clocksource_suspend(struct clocksource *cs) { struct sh_tmu_priv *p = cs_to_sh_tmu(cs); - if (p->cs_enabled) - sh_tmu_disable(p); + if (!p->cs_enabled) + return; - pm_genpd_syscore_poweroff(&p->pdev->dev); + if (--p->enable_count == 0) { + __sh_tmu_disable(p); + pm_genpd_syscore_poweroff(&p->pdev->dev); + } } static void sh_tmu_clocksource_resume(struct clocksource *cs) { struct sh_tmu_priv *p = cs_to_sh_tmu(cs); - pm_genpd_syscore_poweron(&p->pdev->dev); - if (p->cs_enabled) - sh_tmu_enable(p); + if (!p->cs_enabled) + return; + + if (p->enable_count++ == 0) { + pm_genpd_syscore_poweron(&p->pdev->dev); + __sh_tmu_enable(p); + } } static int sh_tmu_register_clocksource(struct sh_tmu_priv *p, @@ -434,6 +472,8 @@ static int sh_tmu_setup(struct sh_tmu_priv *p, struct platform_device *pdev) ret = PTR_ERR(p->clk); goto err1; } + p->cs_enabled = false; + p->enable_count = 0; return sh_tmu_register(p, (char *)dev_name(&p->pdev->dev), cfg->clockevent_rating, @@ -447,18 +487,17 @@ static int sh_tmu_setup(struct sh_tmu_priv *p, struct platform_device *pdev) static int __devinit sh_tmu_probe(struct platform_device *pdev) { struct sh_tmu_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); @@ -471,8 +510,19 @@ static int __devinit sh_tmu_probe(struct platform_device *pdev) if (ret) { kfree(p); platform_set_drvdata(pdev, NULL); + pm_runtime_idle(&pdev->dev); + return ret; } - 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_tmu_remove(struct platform_device *pdev) -- cgit v1.2.3