From: Rafael J. Wysocki Date: Wed, 24 Aug 2011 19:40:56 +0000 (+0200) Subject: PM: Use spinlock instead of mutex in clock management functions X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=b7ab83edba2d50583bc9520431618489379718b2;p=linux-beck.git PM: Use spinlock instead of mutex in clock management functions The lock member of struct pm_clk_data is of type struct mutex, which is a problem, because the suspend and resume routines defined in drivers/base/power/clock_ops.c cannot be executed with interrupts disabled for this reason. Modify struct pm_clk_data so that its lock member is a spinlock. Signed-off-by: Rafael J. Wysocki Acked-by: Magnus Damm --- diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index a846b2f95cfb..2c18d584066d 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -19,7 +19,7 @@ struct pm_clk_data { struct list_head clock_list; - struct mutex lock; + spinlock_t lock; }; enum pce_status { @@ -73,9 +73,9 @@ int pm_clk_add(struct device *dev, const char *con_id) } } - mutex_lock(&pcd->lock); + spin_lock_irq(&pcd->lock); list_add_tail(&ce->node, &pcd->clock_list); - mutex_unlock(&pcd->lock); + spin_unlock_irq(&pcd->lock); return 0; } @@ -83,8 +83,8 @@ int pm_clk_add(struct device *dev, const char *con_id) * __pm_clk_remove - Destroy PM clock entry. * @ce: PM clock entry to destroy. * - * This routine must be called under the mutex protecting the PM list of clocks - * corresponding the the @ce's device. + * This routine must be called under the spinlock protecting the PM list of + * clocks corresponding the the @ce's device. */ static void __pm_clk_remove(struct pm_clock_entry *ce) { @@ -123,7 +123,7 @@ void pm_clk_remove(struct device *dev, const char *con_id) if (!pcd) return; - mutex_lock(&pcd->lock); + spin_lock_irq(&pcd->lock); list_for_each_entry(ce, &pcd->clock_list, node) { if (!con_id && !ce->con_id) { @@ -137,7 +137,7 @@ void pm_clk_remove(struct device *dev, const char *con_id) } } - mutex_unlock(&pcd->lock); + spin_unlock_irq(&pcd->lock); } /** @@ -158,7 +158,7 @@ int pm_clk_init(struct device *dev) } INIT_LIST_HEAD(&pcd->clock_list); - mutex_init(&pcd->lock); + spin_lock_init(&pcd->lock); dev->power.subsys_data = pcd; return 0; } @@ -181,12 +181,12 @@ void pm_clk_destroy(struct device *dev) dev->power.subsys_data = NULL; - mutex_lock(&pcd->lock); + spin_lock_irq(&pcd->lock); list_for_each_entry_safe_reverse(ce, c, &pcd->clock_list, node) __pm_clk_remove(ce); - mutex_unlock(&pcd->lock); + spin_unlock_irq(&pcd->lock); kfree(pcd); } @@ -220,13 +220,14 @@ int pm_clk_suspend(struct device *dev) { struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; + unsigned long flags; dev_dbg(dev, "%s()\n", __func__); if (!pcd) return 0; - mutex_lock(&pcd->lock); + spin_lock_irqsave(&pcd->lock, flags); list_for_each_entry_reverse(ce, &pcd->clock_list, node) { if (ce->status == PCE_STATUS_NONE) @@ -238,7 +239,7 @@ int pm_clk_suspend(struct device *dev) } } - mutex_unlock(&pcd->lock); + spin_unlock_irqrestore(&pcd->lock, flags); return 0; } @@ -251,13 +252,14 @@ int pm_clk_resume(struct device *dev) { struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; + unsigned long flags; dev_dbg(dev, "%s()\n", __func__); if (!pcd) return 0; - mutex_lock(&pcd->lock); + spin_lock_irqsave(&pcd->lock, flags); list_for_each_entry(ce, &pcd->clock_list, node) { if (ce->status == PCE_STATUS_NONE) @@ -269,7 +271,7 @@ int pm_clk_resume(struct device *dev) } } - mutex_unlock(&pcd->lock); + spin_unlock_irqrestore(&pcd->lock, flags); return 0; } @@ -344,6 +346,7 @@ int pm_clk_suspend(struct device *dev) { struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; + unsigned long flags; dev_dbg(dev, "%s()\n", __func__); @@ -351,12 +354,12 @@ int pm_clk_suspend(struct device *dev) if (!pcd || !dev->driver) return 0; - mutex_lock(&pcd->lock); + spin_lock_irqsave(&pcd->lock, flags); list_for_each_entry_reverse(ce, &pcd->clock_list, node) clk_disable(ce->clk); - mutex_unlock(&pcd->lock); + spin_unlock_irqrestore(&pcd->lock, flags); return 0; } @@ -369,6 +372,7 @@ int pm_clk_resume(struct device *dev) { struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; + unsigned long flags; dev_dbg(dev, "%s()\n", __func__); @@ -376,12 +380,12 @@ int pm_clk_resume(struct device *dev) if (!pcd || !dev->driver) return 0; - mutex_lock(&pcd->lock); + spin_lock_irqsave(&pcd->lock, flags); list_for_each_entry(ce, &pcd->clock_list, node) clk_enable(ce->clk); - mutex_unlock(&pcd->lock); + spin_unlock_irqrestore(&pcd->lock, flags); return 0; }