From 4d27e9dcff00a6425d779b065ec8892e4f391661 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 29 Apr 2011 00:35:50 +0200 Subject: PM: Make power domain callbacks take precedence over subsystem ones Change the PM core's behavior related to power domains in such a way that, if a power domain is defined for a given device, its callbacks will be executed instead of and not in addition to the device subsystem's PM callbacks. The idea behind the initial implementation of power domains handling by the PM core was that power domain callbacks would be executed in addition to subsystem callbacks, so that it would be possible to extend the subsystem callbacks by using power domains. It turns out, however, that this wouldn't be really convenient in some important situations. For example, there are systems in which power can only be removed from entire power domains. On those systems it is not desirable to execute device drivers' PM callbacks until it is known that power is going to be removed from the devices in question, which means that they should be executed by power domain callbacks rather then by subsystem (e.g. bus type) PM callbacks, because subsystems generally have no information about what devices belong to which power domain. Thus, for instance, if the bus type in question is the platform bus type, its PM callbacks generally should not be called in addition to power domain callbacks, because they run device drivers' callbacks unconditionally if defined. While in principle the default subsystem PM callbacks, or a subset of them, may be replaced with different functions, it doesn't seem correct to do so, because that would change the subsystem's behavior with respect to all devices in the system, regardless of whether or not they belong to any power domains. Thus, the only remaining option is to make power domain callbacks take precedence over subsystem callbacks. Signed-off-by: Rafael J. Wysocki Acked-by: Grant Likely Acked-by: Kevin Hilman --- drivers/base/power/main.c | 64 +++++++++++++++++++++----------------------- drivers/base/power/runtime.c | 29 +++++++------------- 2 files changed, 41 insertions(+), 52 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index abe3ab709e87..3b354560f306 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -426,10 +426,8 @@ static int device_resume_noirq(struct device *dev, pm_message_t state) if (dev->pwr_domain) { pm_dev_dbg(dev, state, "EARLY power domain "); - pm_noirq_op(dev, &dev->pwr_domain->ops, state); - } - - if (dev->type && dev->type->pm) { + error = pm_noirq_op(dev, &dev->pwr_domain->ops, state); + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "EARLY type "); error = pm_noirq_op(dev, dev->type->pm, state); } else if (dev->class && dev->class->pm) { @@ -517,7 +515,8 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) if (dev->pwr_domain) { pm_dev_dbg(dev, state, "power domain "); - pm_op(dev, &dev->pwr_domain->ops, state); + error = pm_op(dev, &dev->pwr_domain->ops, state); + goto End; } if (dev->type && dev->type->pm) { @@ -629,12 +628,11 @@ static void device_complete(struct device *dev, pm_message_t state) { device_lock(dev); - if (dev->pwr_domain && dev->pwr_domain->ops.complete) { + if (dev->pwr_domain) { pm_dev_dbg(dev, state, "completing power domain "); - dev->pwr_domain->ops.complete(dev); - } - - if (dev->type && dev->type->pm) { + if (dev->pwr_domain->ops.complete) + dev->pwr_domain->ops.complete(dev); + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "completing type "); if (dev->type->pm->complete) dev->type->pm->complete(dev); @@ -732,7 +730,12 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state) { int error; - if (dev->type && dev->type->pm) { + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "LATE power domain "); + error = pm_noirq_op(dev, &dev->pwr_domain->ops, state); + if (error) + return error; + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "LATE type "); error = pm_noirq_op(dev, dev->type->pm, state); if (error) @@ -749,11 +752,6 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state) return error; } - if (dev->pwr_domain) { - pm_dev_dbg(dev, state, "LATE power domain "); - pm_noirq_op(dev, &dev->pwr_domain->ops, state); - } - return 0; } @@ -841,21 +839,27 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) goto End; } + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "power domain "); + error = pm_op(dev, &dev->pwr_domain->ops, state); + goto End; + } + if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "type "); error = pm_op(dev, dev->type->pm, state); - goto Domain; + goto End; } if (dev->class) { if (dev->class->pm) { pm_dev_dbg(dev, state, "class "); error = pm_op(dev, dev->class->pm, state); - goto Domain; + goto End; } else if (dev->class->suspend) { pm_dev_dbg(dev, state, "legacy class "); error = legacy_suspend(dev, state, dev->class->suspend); - goto Domain; + goto End; } } @@ -869,12 +873,6 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) } } - Domain: - if (!error && dev->pwr_domain) { - pm_dev_dbg(dev, state, "power domain "); - pm_op(dev, &dev->pwr_domain->ops, state); - } - End: device_unlock(dev); complete_all(&dev->power.completion); @@ -965,7 +963,14 @@ static int device_prepare(struct device *dev, pm_message_t state) device_lock(dev); - if (dev->type && dev->type->pm) { + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "preparing power domain "); + if (dev->pwr_domain->ops.prepare) + error = dev->pwr_domain->ops.prepare(dev); + suspend_report_result(dev->pwr_domain->ops.prepare, error); + if (error) + goto End; + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "preparing type "); if (dev->type->pm->prepare) error = dev->type->pm->prepare(dev); @@ -984,13 +989,6 @@ static int device_prepare(struct device *dev, pm_message_t state) if (dev->bus->pm->prepare) error = dev->bus->pm->prepare(dev); suspend_report_result(dev->bus->pm->prepare, error); - if (error) - goto End; - } - - if (dev->pwr_domain && dev->pwr_domain->ops.prepare) { - pm_dev_dbg(dev, state, "preparing power domain "); - dev->pwr_domain->ops.prepare(dev); } End: diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 3172c60d23a9..0d4587b15c55 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -168,7 +168,6 @@ static int rpm_check_suspend_allowed(struct device *dev) static int rpm_idle(struct device *dev, int rpmflags) { int (*callback)(struct device *); - int (*domain_callback)(struct device *); int retval; retval = rpm_check_suspend_allowed(dev); @@ -214,7 +213,9 @@ static int rpm_idle(struct device *dev, int rpmflags) dev->power.idle_notification = true; - if (dev->type && dev->type->pm) + if (dev->pwr_domain) + callback = dev->pwr_domain->ops.runtime_idle; + else if (dev->type && dev->type->pm) callback = dev->type->pm->runtime_idle; else if (dev->class && dev->class->pm) callback = dev->class->pm->runtime_idle; @@ -223,19 +224,10 @@ static int rpm_idle(struct device *dev, int rpmflags) else callback = NULL; - if (dev->pwr_domain) - domain_callback = dev->pwr_domain->ops.runtime_idle; - else - domain_callback = NULL; - - if (callback || domain_callback) { + if (callback) { spin_unlock_irq(&dev->power.lock); - if (domain_callback) - retval = domain_callback(dev); - - if (!retval && callback) - callback(dev); + callback(dev); spin_lock_irq(&dev->power.lock); } @@ -382,7 +374,9 @@ static int rpm_suspend(struct device *dev, int rpmflags) __update_runtime_status(dev, RPM_SUSPENDING); - if (dev->type && dev->type->pm) + if (dev->pwr_domain) + callback = dev->pwr_domain->ops.runtime_suspend; + else if (dev->type && dev->type->pm) callback = dev->type->pm->runtime_suspend; else if (dev->class && dev->class->pm) callback = dev->class->pm->runtime_suspend; @@ -400,8 +394,6 @@ static int rpm_suspend(struct device *dev, int rpmflags) else pm_runtime_cancel_pending(dev); } else { - if (dev->pwr_domain) - rpm_callback(dev->pwr_domain->ops.runtime_suspend, dev); no_callback: __update_runtime_status(dev, RPM_SUSPENDED); pm_runtime_deactivate_timer(dev); @@ -582,9 +574,8 @@ static int rpm_resume(struct device *dev, int rpmflags) __update_runtime_status(dev, RPM_RESUMING); if (dev->pwr_domain) - rpm_callback(dev->pwr_domain->ops.runtime_resume, dev); - - if (dev->type && dev->type->pm) + callback = dev->pwr_domain->ops.runtime_resume; + else if (dev->type && dev->type->pm) callback = dev->type->pm->runtime_resume; else if (dev->class && dev->class->pm) callback = dev->class->pm->runtime_resume; -- cgit v1.2.2 From 85eb8c8d0b0900c073b0e6f89979ac9c439ade1a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 30 Apr 2011 00:25:44 +0200 Subject: PM / Runtime: Generic clock manipulation rountines for runtime PM (v6) Many different platforms and subsystems may want to disable device clocks during suspend and enable them during resume which is going to be done in a very similar way in all those cases. For this reason, provide generic routines for the manipulation of device clocks during suspend and resume. Convert the ARM shmobile platform to using the new routines. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/Makefile | 1 + drivers/base/power/clock_ops.c | 430 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 431 insertions(+) create mode 100644 drivers/base/power/clock_ops.c (limited to 'drivers/base/power') diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile index 118c1b92a511..06a7073f9027 100644 --- a/drivers/base/power/Makefile +++ b/drivers/base/power/Makefile @@ -3,6 +3,7 @@ obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o obj-$(CONFIG_PM_RUNTIME) += runtime.o obj-$(CONFIG_PM_TRACE_RTC) += trace.o obj-$(CONFIG_PM_OPP) += opp.o +obj-$(CONFIG_HAVE_CLK) += clock_ops.o ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG ccflags-$(CONFIG_PM_VERBOSE) += -DDEBUG diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c new file mode 100644 index 000000000000..d74abf334391 --- /dev/null +++ b/drivers/base/power/clock_ops.c @@ -0,0 +1,430 @@ +/* + * drivers/base/power/clock_ops.c - Generic clock manipulation PM callbacks + * + * Copyright (c) 2011 Rafael J. Wysocki , Renesas Electronics Corp. + * + * This file is released under the GPLv2. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_PM_RUNTIME + +struct pm_runtime_clk_data { + struct list_head clock_list; + struct mutex lock; +}; + +enum pce_status { + PCE_STATUS_NONE = 0, + PCE_STATUS_ACQUIRED, + PCE_STATUS_ENABLED, + PCE_STATUS_ERROR, +}; + +struct pm_clock_entry { + struct list_head node; + char *con_id; + struct clk *clk; + enum pce_status status; +}; + +static struct pm_runtime_clk_data *__to_prd(struct device *dev) +{ + return dev ? dev->power.subsys_data : NULL; +} + +/** + * pm_runtime_clk_add - Start using a device clock for runtime PM. + * @dev: Device whose clock is going to be used for runtime PM. + * @con_id: Connection ID of the clock. + * + * Add the clock represented by @con_id to the list of clocks used for + * the runtime PM of @dev. + */ +int pm_runtime_clk_add(struct device *dev, const char *con_id) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + if (!prd) + return -EINVAL; + + ce = kzalloc(sizeof(*ce), GFP_KERNEL); + if (!ce) { + dev_err(dev, "Not enough memory for clock entry.\n"); + return -ENOMEM; + } + + if (con_id) { + ce->con_id = kstrdup(con_id, GFP_KERNEL); + if (!ce->con_id) { + dev_err(dev, + "Not enough memory for clock connection ID.\n"); + kfree(ce); + return -ENOMEM; + } + } + + mutex_lock(&prd->lock); + list_add_tail(&ce->node, &prd->clock_list); + mutex_unlock(&prd->lock); + return 0; +} + +/** + * __pm_runtime_clk_remove - Destroy runtime PM clock entry. + * @ce: Runtime PM clock entry to destroy. + * + * This routine must be called under the mutex protecting the runtime PM list + * of clocks corresponding the the @ce's device. + */ +static void __pm_runtime_clk_remove(struct pm_clock_entry *ce) +{ + if (!ce) + return; + + list_del(&ce->node); + + if (ce->status < PCE_STATUS_ERROR) { + if (ce->status == PCE_STATUS_ENABLED) + clk_disable(ce->clk); + + if (ce->status >= PCE_STATUS_ACQUIRED) + clk_put(ce->clk); + } + + if (ce->con_id) + kfree(ce->con_id); + + kfree(ce); +} + +/** + * pm_runtime_clk_remove - Stop using a device clock for runtime PM. + * @dev: Device whose clock should not be used for runtime PM any more. + * @con_id: Connection ID of the clock. + * + * Remove the clock represented by @con_id from the list of clocks used for + * the runtime PM of @dev. + */ +void pm_runtime_clk_remove(struct device *dev, const char *con_id) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + if (!prd) + return; + + mutex_lock(&prd->lock); + + list_for_each_entry(ce, &prd->clock_list, node) { + if (!con_id && !ce->con_id) { + __pm_runtime_clk_remove(ce); + break; + } else if (!con_id || !ce->con_id) { + continue; + } else if (!strcmp(con_id, ce->con_id)) { + __pm_runtime_clk_remove(ce); + break; + } + } + + mutex_unlock(&prd->lock); +} + +/** + * pm_runtime_clk_init - Initialize a device's list of runtime PM clocks. + * @dev: Device to initialize the list of runtime PM clocks for. + * + * Allocate a struct pm_runtime_clk_data object, initialize its lock member and + * make the @dev's power.subsys_data field point to it. + */ +int pm_runtime_clk_init(struct device *dev) +{ + struct pm_runtime_clk_data *prd; + + prd = kzalloc(sizeof(*prd), GFP_KERNEL); + if (!prd) { + dev_err(dev, "Not enough memory fo runtime PM data.\n"); + return -ENOMEM; + } + + INIT_LIST_HEAD(&prd->clock_list); + mutex_init(&prd->lock); + dev->power.subsys_data = prd; + return 0; +} + +/** + * pm_runtime_clk_destroy - Destroy a device's list of runtime PM clocks. + * @dev: Device to destroy the list of runtime PM clocks for. + * + * Clear the @dev's power.subsys_data field, remove the list of clock entries + * from the struct pm_runtime_clk_data object pointed to by it before and free + * that object. + */ +void pm_runtime_clk_destroy(struct device *dev) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce, *c; + + if (!prd) + return; + + dev->power.subsys_data = NULL; + + mutex_lock(&prd->lock); + + list_for_each_entry_safe_reverse(ce, c, &prd->clock_list, node) + __pm_runtime_clk_remove(ce); + + mutex_unlock(&prd->lock); + + kfree(prd); +} + +/** + * pm_runtime_clk_acquire - Acquire a device clock. + * @dev: Device whose clock is to be acquired. + * @con_id: Connection ID of the clock. + */ +static void pm_runtime_clk_acquire(struct device *dev, + struct pm_clock_entry *ce) +{ + ce->clk = clk_get(dev, ce->con_id); + if (IS_ERR(ce->clk)) { + ce->status = PCE_STATUS_ERROR; + } else { + ce->status = PCE_STATUS_ACQUIRED; + dev_dbg(dev, "Clock %s managed by runtime PM.\n", ce->con_id); + } +} + +/** + * pm_runtime_clk_suspend - Disable clocks in a device's runtime PM clock list. + * @dev: Device to disable the clocks for. + */ +int pm_runtime_clk_suspend(struct device *dev) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + dev_dbg(dev, "%s()\n", __func__); + + if (!prd) + return 0; + + mutex_lock(&prd->lock); + + list_for_each_entry_reverse(ce, &prd->clock_list, node) { + if (ce->status == PCE_STATUS_NONE) + pm_runtime_clk_acquire(dev, ce); + + if (ce->status < PCE_STATUS_ERROR) { + clk_disable(ce->clk); + ce->status = PCE_STATUS_ACQUIRED; + } + } + + mutex_unlock(&prd->lock); + + return 0; +} + +/** + * pm_runtime_clk_resume - Enable clocks in a device's runtime PM clock list. + * @dev: Device to enable the clocks for. + */ +int pm_runtime_clk_resume(struct device *dev) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + dev_dbg(dev, "%s()\n", __func__); + + if (!prd) + return 0; + + mutex_lock(&prd->lock); + + list_for_each_entry(ce, &prd->clock_list, node) { + if (ce->status == PCE_STATUS_NONE) + pm_runtime_clk_acquire(dev, ce); + + if (ce->status < PCE_STATUS_ERROR) { + clk_enable(ce->clk); + ce->status = PCE_STATUS_ENABLED; + } + } + + mutex_unlock(&prd->lock); + + return 0; +} + +/** + * pm_runtime_clk_notify - Notify routine for device addition and removal. + * @nb: Notifier block object this function is a member of. + * @action: Operation being carried out by the caller. + * @data: Device the routine is being run for. + * + * For this function to work, @nb must be a member of an object of type + * struct pm_clk_notifier_block containing all of the requisite data. + * Specifically, the pwr_domain member of that object is copied to the device's + * pwr_domain field and its con_ids member is used to populate the device's list + * of runtime PM clocks, depending on @action. + * + * If the device's pwr_domain field is already populated with a value different + * from the one stored in the struct pm_clk_notifier_block object, the function + * does nothing. + */ +static int pm_runtime_clk_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pm_clk_notifier_block *clknb; + struct device *dev = data; + char *con_id; + int error; + + dev_dbg(dev, "%s() %ld\n", __func__, action); + + clknb = container_of(nb, struct pm_clk_notifier_block, nb); + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + if (dev->pwr_domain) + break; + + error = pm_runtime_clk_init(dev); + if (error) + break; + + dev->pwr_domain = clknb->pwr_domain; + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids[0]; *con_id; con_id++) + pm_runtime_clk_add(dev, con_id); + } else { + pm_runtime_clk_add(dev, NULL); + } + + break; + case BUS_NOTIFY_DEL_DEVICE: + if (dev->pwr_domain != clknb->pwr_domain) + break; + + dev->pwr_domain = NULL; + pm_runtime_clk_destroy(dev); + break; + } + + return 0; +} + +#else /* !CONFIG_PM_RUNTIME */ + +/** + * enable_clock - Enable a device clock. + * @dev: Device whose clock is to be enabled. + * @con_id: Connection ID of the clock. + */ +static void enable_clock(struct device *dev, const char *con_id) +{ + struct clk *clk; + + clk = clk_get(dev, con_id); + if (!IS_ERR(clk)) { + clk_enable(clk); + clk_put(clk); + dev_info(dev, "Runtime PM disabled, clock forced on.\n"); + } +} + +/** + * disable_clock - Disable a device clock. + * @dev: Device whose clock is to be disabled. + * @con_id: Connection ID of the clock. + */ +static void disable_clock(struct device *dev, const char *con_id) +{ + struct clk *clk; + + clk = clk_get(dev, con_id); + if (!IS_ERR(clk)) { + clk_disable(clk); + clk_put(clk); + dev_info(dev, "Runtime PM disabled, clock forced off.\n"); + } +} + +/** + * pm_runtime_clk_notify - Notify routine for device addition and removal. + * @nb: Notifier block object this function is a member of. + * @action: Operation being carried out by the caller. + * @data: Device the routine is being run for. + * + * For this function to work, @nb must be a member of an object of type + * struct pm_clk_notifier_block containing all of the requisite data. + * Specifically, the con_ids member of that object is used to enable or disable + * the device's clocks, depending on @action. + */ +static int pm_runtime_clk_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pm_clk_notifier_block *clknb; + struct device *dev = data; + + dev_dbg(dev, "%s() %ld\n", __func__, action); + + clknb = container_of(nb, struct pm_clk_notifier_block, nb); + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids[0]; *con_id; con_id++) + enable_clock(dev, con_id); + } else { + enable_clock(dev, NULL); + } + break; + case BUS_NOTIFY_DEL_DEVICE: + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids[0]; *con_id; con_id++) + disable_clock(dev, con_id); + } else { + disable_clock(dev, NULL); + } + break; + } + + return 0; +} + +#endif /* !CONFIG_PM_RUNTIME */ + +/** + * pm_runtime_clk_add_notifier - Add bus type notifier for runtime PM clocks. + * @bus: Bus type to add the notifier to. + * @clknb: Notifier to be added to the given bus type. + * + * The nb member of @clknb is not expected to be initialized and its + * notifier_call member will be replaced with pm_runtime_clk_notify(). However, + * the remaining members of @clknb should be populated prior to calling this + * routine. + */ +void pm_runtime_clk_add_notifier(struct bus_type *bus, + struct pm_clk_notifier_block *clknb) +{ + if (!bus || !clknb) + return; + + clknb->nb.notifier_call = pm_runtime_clk_notify; + bus_register_notifier(bus, &clknb->nb); +} -- cgit v1.2.2 From 72874daa5e9064c4e8d689e6a04b1e96f687f872 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 3 May 2011 19:45:32 +0200 Subject: PM: Fix build issue in clock_ops.c for CONFIG_PM_RUNTIME unset Fix a build issue in drivers/base/power/clock_ops.c occuring when CONFIG_PM_RUNTIME is not set. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/clock_ops.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/base/power') diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index d74abf334391..c0dd09df7be8 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -380,6 +380,7 @@ static int pm_runtime_clk_notify(struct notifier_block *nb, { struct pm_clk_notifier_block *clknb; struct device *dev = data; + char *con_id; dev_dbg(dev, "%s() %ld\n", __func__, action); -- cgit v1.2.2