From 3a7cbd50f74907580eb47a8d08e1f29741b81abf Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 21 Nov 2011 12:32:22 -0800 Subject: freezer: don't unnecessarily set PF_NOFREEZE explicitly Some drivers set PF_NOFREEZE in their kthread functions which is completely unnecessary and racy - some part of freezer code doesn't consider cases where PF_NOFREEZE is set asynchronous to freezer operations. In general, there's no reason to allow setting PF_NOFREEZE explicitly. Remove them and change the documentation to note that setting PF_NOFREEZE directly isn't allowed. -v2: Dropped change to twl4030-irq.c as it no longer uses PF_NOFREEZE. Signed-off-by: Tejun Heo Acked-by: "Gustavo F. Padovan" Acked-by: Samuel Ortiz Cc: Marcel Holtmann Cc: wwang --- Documentation/power/freezing-of-tasks.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation/power') diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt index 316c2ba187f4..587e0828053f 100644 --- a/Documentation/power/freezing-of-tasks.txt +++ b/Documentation/power/freezing-of-tasks.txt @@ -67,7 +67,7 @@ III. Which kernel threads are freezable? Kernel threads are not freezable by default. However, a kernel thread may clear PF_NOFREEZE for itself by calling set_freezable() (the resetting of PF_NOFREEZE -directly is strongly discouraged). From this point it is regarded as freezable +directly is not allowed). From this point it is regarded as freezable and must call try_to_freeze() in a suitable place. IV. Why do we do that? -- cgit v1.2.3 From a0acae0e886d44bd5ce6d2f173c1ace0fcf0d9f6 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 21 Nov 2011 12:32:22 -0800 Subject: freezer: unexport refrigerator() and update try_to_freeze() slightly There is no reason to export two functions for entering the refrigerator. Calling refrigerator() instead of try_to_freeze() doesn't save anything noticeable or removes any race condition. * Rename refrigerator() to __refrigerator() and make it return bool indicating whether it scheduled out for freezing. * Update try_to_freeze() to return bool and relay the return value of __refrigerator() if freezing(). * Convert all refrigerator() users to try_to_freeze(). * Update documentation accordingly. * While at it, add might_sleep() to try_to_freeze(). Signed-off-by: Tejun Heo Cc: Samuel Ortiz Cc: Chris Mason Cc: "Theodore Ts'o" Cc: Steven Whitehouse Cc: Andrew Morton Cc: Jan Kara Cc: KONISHI Ryusuke Cc: Christoph Hellwig --- Documentation/power/freezing-of-tasks.txt | 12 ++++++------ drivers/net/irda/stir4200.c | 2 +- fs/btrfs/async-thread.c | 2 +- fs/btrfs/disk-io.c | 8 ++------ fs/ext4/super.c | 3 +-- fs/gfs2/log.c | 4 ++-- fs/gfs2/quota.c | 4 ++-- fs/jbd/journal.c | 2 +- fs/jbd2/journal.c | 2 +- fs/jfs/jfs_logmgr.c | 2 +- fs/jfs/jfs_txnmgr.c | 4 ++-- fs/nilfs2/segment.c | 2 +- fs/xfs/xfs_buf.c | 2 +- include/linux/freezer.h | 17 ++++++++--------- kernel/freezer.c | 10 +++++++--- 15 files changed, 37 insertions(+), 39 deletions(-) (limited to 'Documentation/power') diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt index 587e0828053f..3ab9fbd2800a 100644 --- a/Documentation/power/freezing-of-tasks.txt +++ b/Documentation/power/freezing-of-tasks.txt @@ -21,7 +21,7 @@ freeze_processes() (defined in kernel/power/process.c) is called. It executes try_to_freeze_tasks() that sets TIF_FREEZE for all of the freezable tasks and either wakes them up, if they are kernel threads, or sends fake signals to them, if they are user space processes. A task that has TIF_FREEZE set, should react -to it by calling the function called refrigerator() (defined in +to it by calling the function called __refrigerator() (defined in kernel/freezer.c), which sets the task's PF_FROZEN flag, changes its state to TASK_UNINTERRUPTIBLE and makes it loop until PF_FROZEN is cleared for it. Then, we say that the task is 'frozen' and therefore the set of functions @@ -29,10 +29,10 @@ handling this mechanism is referred to as 'the freezer' (these functions are defined in kernel/power/process.c, kernel/freezer.c & include/linux/freezer.h). User space processes are generally frozen before kernel threads. -It is not recommended to call refrigerator() directly. Instead, it is -recommended to use the try_to_freeze() function (defined in -include/linux/freezer.h), that checks the task's TIF_FREEZE flag and makes the -task enter refrigerator() if the flag is set. +__refrigerator() must not be called directly. Instead, use the +try_to_freeze() function (defined in include/linux/freezer.h), that checks +the task's TIF_FREEZE flag and makes the task enter __refrigerator() if the +flag is set. For user space processes try_to_freeze() is called automatically from the signal-handling code, but the freezable kernel threads need to call it @@ -61,7 +61,7 @@ wait_event_freezable() and wait_event_freezable_timeout() macros. After the system memory state has been restored from a hibernation image and devices have been reinitialized, the function thaw_processes() is called in order to clear the PF_FROZEN flag for each frozen task. Then, the tasks that -have been frozen leave refrigerator() and continue running. +have been frozen leave __refrigerator() and continue running. III. Which kernel threads are freezable? diff --git a/drivers/net/irda/stir4200.c b/drivers/net/irda/stir4200.c index 41c96b3d8152..e880c79d7bd8 100644 --- a/drivers/net/irda/stir4200.c +++ b/drivers/net/irda/stir4200.c @@ -750,7 +750,7 @@ static int stir_transmit_thread(void *arg) write_reg(stir, REG_CTRL1, CTRL1_TXPWD|CTRL1_RXPWD); - refrigerator(); + try_to_freeze(); if (change_speed(stir, stir->speed)) break; diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c index 7ec14097fef1..98ab240072e5 100644 --- a/fs/btrfs/async-thread.c +++ b/fs/btrfs/async-thread.c @@ -340,7 +340,7 @@ again: if (freezing(current)) { worker->working = 0; spin_unlock_irq(&worker->lock); - refrigerator(); + try_to_freeze(); } else { spin_unlock_irq(&worker->lock); if (!kthread_should_stop()) { diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 62afe5c5694e..622654fe051f 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1579,9 +1579,7 @@ static int cleaner_kthread(void *arg) btrfs_run_defrag_inodes(root->fs_info); } - if (freezing(current)) { - refrigerator(); - } else { + if (!try_to_freeze()) { set_current_state(TASK_INTERRUPTIBLE); if (!kthread_should_stop()) schedule(); @@ -1635,9 +1633,7 @@ sleep: wake_up_process(root->fs_info->cleaner_kthread); mutex_unlock(&root->fs_info->transaction_kthread_mutex); - if (freezing(current)) { - refrigerator(); - } else { + if (!try_to_freeze()) { set_current_state(TASK_INTERRUPTIBLE); if (!kthread_should_stop() && !btrfs_transaction_blocked(root->fs_info)) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 9953d80145ad..877350ef0253 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2882,8 +2882,7 @@ cont_thread: } mutex_unlock(&eli->li_list_mtx); - if (freezing(current)) - refrigerator(); + try_to_freeze(); cur = jiffies; if ((time_after_eq(cur, next_wakeup)) || diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index 598646434362..8154d42e4647 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -951,8 +951,8 @@ int gfs2_logd(void *data) wake_up(&sdp->sd_log_waitq); t = gfs2_tune_get(sdp, gt_logd_secs) * HZ; - if (freezing(current)) - refrigerator(); + + try_to_freeze(); do { prepare_to_wait(&sdp->sd_logd_waitq, &wait, diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c index 7e528dc14f85..d49669e92652 100644 --- a/fs/gfs2/quota.c +++ b/fs/gfs2/quota.c @@ -1427,8 +1427,8 @@ int gfs2_quotad(void *data) /* Check for & recover partially truncated inodes */ quotad_check_trunc_list(sdp); - if (freezing(current)) - refrigerator(); + try_to_freeze(); + t = min(quotad_timeo, statfs_timeo); prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE); diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c index fea8dd661d2b..a96cff0c5f1d 100644 --- a/fs/jbd/journal.c +++ b/fs/jbd/journal.c @@ -166,7 +166,7 @@ loop: */ jbd_debug(1, "Now suspending kjournald\n"); spin_unlock(&journal->j_state_lock); - refrigerator(); + try_to_freeze(); spin_lock(&journal->j_state_lock); } else { /* diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 0fa0123151d3..c0a5f9f1b127 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -173,7 +173,7 @@ loop: */ jbd_debug(1, "Now suspending kjournald2\n"); write_unlock(&journal->j_state_lock); - refrigerator(); + try_to_freeze(); write_lock(&journal->j_state_lock); } else { /* diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c index cc5f811ed383..2eb952c41a69 100644 --- a/fs/jfs/jfs_logmgr.c +++ b/fs/jfs/jfs_logmgr.c @@ -2349,7 +2349,7 @@ int jfsIOWait(void *arg) if (freezing(current)) { spin_unlock_irq(&log_redrive_lock); - refrigerator(); + try_to_freeze(); } else { set_current_state(TASK_INTERRUPTIBLE); spin_unlock_irq(&log_redrive_lock); diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c index af9606057dde..bb8b661bcc50 100644 --- a/fs/jfs/jfs_txnmgr.c +++ b/fs/jfs/jfs_txnmgr.c @@ -2800,7 +2800,7 @@ int jfs_lazycommit(void *arg) if (freezing(current)) { LAZY_UNLOCK(flags); - refrigerator(); + try_to_freeze(); } else { DECLARE_WAITQUEUE(wq, current); @@ -2994,7 +2994,7 @@ int jfs_sync(void *arg) if (freezing(current)) { TXN_UNLOCK(); - refrigerator(); + try_to_freeze(); } else { set_current_state(TASK_INTERRUPTIBLE); TXN_UNLOCK(); diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c index bb24ab6c282f..0e72ad6f22aa 100644 --- a/fs/nilfs2/segment.c +++ b/fs/nilfs2/segment.c @@ -2470,7 +2470,7 @@ static int nilfs_segctor_thread(void *arg) if (freezing(current)) { spin_unlock(&sci->sc_state_lock); - refrigerator(); + try_to_freeze(); spin_lock(&sci->sc_state_lock); } else { DEFINE_WAIT(wait); diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index cf0ac056815f..018829936d6d 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -1703,7 +1703,7 @@ xfsbufd( if (unlikely(freezing(current))) { set_bit(XBT_FORCE_SLEEP, &target->bt_flags); - refrigerator(); + try_to_freeze(); } else { clear_bit(XBT_FORCE_SLEEP, &target->bt_flags); } diff --git a/include/linux/freezer.h b/include/linux/freezer.h index a5386e3ee756..7a9427e9fe47 100644 --- a/include/linux/freezer.h +++ b/include/linux/freezer.h @@ -47,18 +47,17 @@ static inline bool should_send_signal(struct task_struct *p) /* Takes and releases task alloc lock using task_lock() */ extern int thaw_process(struct task_struct *p); -extern void refrigerator(void); +extern bool __refrigerator(void); extern int freeze_processes(void); extern int freeze_kernel_threads(void); extern void thaw_processes(void); -static inline int try_to_freeze(void) +static inline bool try_to_freeze(void) { - if (freezing(current)) { - refrigerator(); - return 1; - } else - return 0; + might_sleep(); + if (likely(!freezing(current))) + return false; + return __refrigerator(); } extern bool freeze_task(struct task_struct *p, bool sig_only); @@ -181,12 +180,12 @@ static inline void set_freeze_flag(struct task_struct *p) {} static inline void clear_freeze_flag(struct task_struct *p) {} static inline int thaw_process(struct task_struct *p) { return 1; } -static inline void refrigerator(void) {} +static inline bool __refrigerator(void) { return false; } static inline int freeze_processes(void) { return -ENOSYS; } static inline int freeze_kernel_threads(void) { return -ENOSYS; } static inline void thaw_processes(void) {} -static inline int try_to_freeze(void) { return 0; } +static inline bool try_to_freeze(void) { return false; } static inline void freezer_do_not_count(void) {} static inline void freezer_count(void) {} diff --git a/kernel/freezer.c b/kernel/freezer.c index 3f460104a9d6..732f14f5944f 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -23,10 +23,11 @@ static inline void frozen_process(void) } /* Refrigerator is place where frozen processes are stored :-). */ -void refrigerator(void) +bool __refrigerator(void) { /* Hmm, should we be allowed to suspend when there are realtime processes around? */ + bool was_frozen = false; long save; task_lock(current); @@ -35,7 +36,7 @@ void refrigerator(void) task_unlock(current); } else { task_unlock(current); - return; + return was_frozen; } save = current->state; pr_debug("%s entered refrigerator\n", current->comm); @@ -51,6 +52,7 @@ void refrigerator(void) set_current_state(TASK_UNINTERRUPTIBLE); if (!frozen(current)) break; + was_frozen = true; schedule(); } @@ -65,8 +67,10 @@ void refrigerator(void) * synchronization which depends on ordered task state change. */ set_current_state(save); + + return was_frozen; } -EXPORT_SYMBOL(refrigerator); +EXPORT_SYMBOL(__refrigerator); static void fake_signal_wake_up(struct task_struct *p) { -- cgit v1.2.3 From 068df0f34e81bc06c5eb5012ec2eda25624e87aa Mon Sep 17 00:00:00 2001 From: Rajendra Nayak Date: Mon, 5 Dec 2011 12:47:42 +0530 Subject: regulator: Fix regulator_register() API signature in Documentation The commit 2c043bcbf287 ("regulator: pass additional of_node to regulator_register()") added an additional parameter to the regulator_register() API. Update the Documentation accordingly to reflect the change in the function signature. Reported-by: Thomas Abraham Signed-off-by: Rajendra Nayak Signed-off-by: Mark Brown --- Documentation/power/regulator/regulator.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation/power') diff --git a/Documentation/power/regulator/regulator.txt b/Documentation/power/regulator/regulator.txt index 3f8b528f237e..e272d9909e39 100644 --- a/Documentation/power/regulator/regulator.txt +++ b/Documentation/power/regulator/regulator.txt @@ -12,7 +12,7 @@ Drivers can register a regulator by calling :- struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, struct device *dev, struct regulator_init_data *init_data, - void *driver_data); + void *driver_data, struct device_node *of_node); This will register the regulators capabilities and operations to the regulator core. -- cgit v1.2.3 From cba3176e88fa134ece3ae1cf7e35dab9972d7853 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Wed, 7 Dec 2011 22:30:09 +0100 Subject: PM / Sleep: Recommend [un]lock_system_sleep() over using pm_mutex directly Update the documentation to explain the perils of directly using mutex_[un]lock(&pm_mutex) and recommend the usage of the safe APIs [un]lock_system_sleep() instead. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- Documentation/power/freezing-of-tasks.txt | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'Documentation/power') diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt index 3ab9fbd2800a..6ccb68f68da6 100644 --- a/Documentation/power/freezing-of-tasks.txt +++ b/Documentation/power/freezing-of-tasks.txt @@ -176,3 +176,28 @@ tasks, since it generally exists anyway. A driver must have all firmwares it may need in RAM before suspend() is called. If keeping them is not practical, for example due to their size, they must be requested early enough using the suspend notifier API described in notifiers.txt. + +VI. Are there any precautions to be taken to prevent freezing failures? + +Yes, there are. + +First of all, grabbing the 'pm_mutex' lock to mutually exclude a piece of code +from system-wide sleep such as suspend/hibernation is not encouraged. +If possible, that piece of code must instead hook onto the suspend/hibernation +notifiers to achieve mutual exclusion. Look at the CPU-Hotplug code +(kernel/cpu.c) for an example. + +However, if that is not feasible, and grabbing 'pm_mutex' is deemed necessary, +it is strongly discouraged to directly call mutex_[un]lock(&pm_mutex) since +that could lead to freezing failures, because if the suspend/hibernate code +successfully acquired the 'pm_mutex' lock, and hence that other entity failed +to acquire the lock, then that task would get blocked in TASK_UNINTERRUPTIBLE +state. As a consequence, the freezer would not be able to freeze that task, +leading to freezing failure. + +However, the [un]lock_system_sleep() APIs are safe to use in this scenario, +since they ask the freezer to skip freezing this task, since it is anyway +"frozen enough" as it is blocked on 'pm_mutex', which will be released +only after the entire suspend/hibernation sequence is complete. +So, to summarize, use [un]lock_system_sleep() instead of directly using +mutex_[un]lock(&pm_mutex). That would prevent freezing failures. -- cgit v1.2.3 From 35cd133c6130c1eb52806808abee9d62e6854a27 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 18 Dec 2011 00:34:13 +0100 Subject: PM: Run the driver callback directly if the subsystem one is not there Make the PM core execute driver PM callbacks directly if the corresponding subsystem callbacks are not present. There are three reasons for doing that. First, it reflects the behavior of drivers/base/dd.c:really_probe() that runs the driver's .probe() callback directly if the bus type's one is not defined, so this change will remove one arbitrary difference between the PM core and the remaining parts of the driver core. Second, it will allow some subsystems, whose PM callbacks don't do anything except for executing driver callbacks, to be simplified quite a bit by removing those "forward-only" callbacks. Finally, it will allow us to remove one level of indirection in the system suspend and resume code paths where it is not necessary, which is going to lead to less debug noise with initcall_debug passed in the kernel command line (messages won't be printed for driverless devices whose subsystems don't provide PM callbacks among other things). Signed-off-by: Rafael J. Wysocki --- Documentation/power/devices.txt | 37 ++++++----- Documentation/power/runtime_pm.txt | 130 +++++++++++++++++++------------------ drivers/base/power/main.c | 109 ++++++++++++++++++++----------- drivers/base/power/runtime.c | 9 +++ 4 files changed, 170 insertions(+), 115 deletions(-) (limited to 'Documentation/power') diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 3139fb505dce..20af7def23c8 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -126,7 +126,9 @@ The core methods to suspend and resume devices reside in struct dev_pm_ops pointed to by the ops member of struct dev_pm_domain, or by the pm member of struct bus_type, struct device_type and struct class. They are mostly of interest to the people writing infrastructure for platforms and buses, like PCI -or USB, or device type and device class drivers. +or USB, or device type and device class drivers. They also are relevant to the +writers of device drivers whose subsystems (PM domains, device types, device +classes and bus types) don't provide all power management methods. Bus drivers implement these methods as appropriate for the hardware and the drivers using it; PCI works differently from USB, and so on. Not many people @@ -268,32 +270,35 @@ various phases always run after tasks have been frozen and before they are unfrozen. Furthermore, the *_noirq phases run at a time when IRQ handlers have been disabled (except for those marked with the IRQF_NO_SUSPEND flag). -All phases use PM domain, bus, type, or class callbacks (that is, methods -defined in dev->pm_domain->ops, dev->bus->pm, dev->type->pm, or dev->class->pm). -These callbacks are regarded by the PM core as mutually exclusive. Moreover, -PM domain callbacks always take precedence over bus, type and class callbacks, -while type callbacks take precedence over bus and class callbacks, and class -callbacks take precedence over bus callbacks. To be precise, the following -rules are used to determine which callback to execute in the given phase: +All phases use PM domain, bus, type, class or driver callbacks (that is, methods +defined in dev->pm_domain->ops, dev->bus->pm, dev->type->pm, dev->class->pm or +dev->driver->pm). These callbacks are regarded by the PM core as mutually +exclusive. Moreover, PM domain callbacks always take precedence over all of the +other callbacks and, for example, type callbacks take precedence over bus, class +and driver callbacks. To be precise, the following rules are used to determine +which callback to execute in the given phase: - 1. If dev->pm_domain is present, the PM core will attempt to execute the - callback included in dev->pm_domain->ops. If that callback is not - present, no action will be carried out for the given device. + 1. If dev->pm_domain is present, the PM core will choose the callback + included in dev->pm_domain->ops for execution 2. Otherwise, if both dev->type and dev->type->pm are present, the callback - included in dev->type->pm will be executed. + included in dev->type->pm will be chosen for execution. 3. Otherwise, if both dev->class and dev->class->pm are present, the - callback included in dev->class->pm will be executed. + callback included in dev->class->pm will be chosen for execution. 4. Otherwise, if both dev->bus and dev->bus->pm are present, the callback - included in dev->bus->pm will be executed. + included in dev->bus->pm will be chosen for execution. This allows PM domains and device types to override callbacks provided by bus types or device classes if necessary. -These callbacks may in turn invoke device- or driver-specific methods stored in -dev->driver->pm, but they don't have to. +The PM domain, type, class and bus callbacks may in turn invoke device- or +driver-specific methods stored in dev->driver->pm, but they don't have to do +that. + +If the subsystem callback chosen for execution is not present, the PM core will +execute the corresponding method from dev->driver->pm instead if there is one. Entering System Suspend diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index c2ae8bf77d46..4abe83e1045a 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -57,6 +57,10 @@ the following: 4. Bus type of the device, if both dev->bus and dev->bus->pm are present. +If the subsystem chosen by applying the above rules doesn't provide the relevant +callback, the PM core will invoke the corresponding driver callback stored in +dev->driver->pm directly (if present). + The PM core always checks which callback to use in the order given above, so the priority order of callbacks from high to low is: PM domain, device type, class and bus type. Moreover, the high-priority one will always take precedence over @@ -64,86 +68,88 @@ a low-priority one. The PM domain, bus type, device type and class callbacks are referred to as subsystem-level callbacks in what follows. By default, the callbacks are always invoked in process context with interrupts -enabled. However, subsystems can use the pm_runtime_irq_safe() helper function -to tell the PM core that their ->runtime_suspend(), ->runtime_resume() and -->runtime_idle() callbacks may be invoked in atomic context with interrupts -disabled for a given device. This implies that the callback routines in -question must not block or sleep, but it also means that the synchronous helper -functions listed at the end of Section 4 may be used for that device within an -interrupt handler or generally in an atomic context. - -The subsystem-level suspend callback is _entirely_ _responsible_ for handling -the suspend of the device as appropriate, which may, but need not include -executing the device driver's own ->runtime_suspend() callback (from the +enabled. However, the pm_runtime_irq_safe() helper function can be used to tell +the PM core that it is safe to run the ->runtime_suspend(), ->runtime_resume() +and ->runtime_idle() callbacks for the given device in atomic context with +interrupts disabled. This implies that the callback routines in question must +not block or sleep, but it also means that the synchronous helper functions +listed at the end of Section 4 may be used for that device within an interrupt +handler or generally in an atomic context. + +The subsystem-level suspend callback, if present, is _entirely_ _responsible_ +for handling the suspend of the device as appropriate, which may, but need not +include executing the device driver's own ->runtime_suspend() callback (from the PM core's point of view it is not necessary to implement a ->runtime_suspend() callback in a device driver as long as the subsystem-level suspend callback knows what to do to handle the device). - * Once the subsystem-level suspend callback has completed successfully - for given device, the PM core regards the device as suspended, which need - not mean that the device has been put into a low power state. It is - supposed to mean, however, that the device will not process data and will - not communicate with the CPU(s) and RAM until the subsystem-level resume - callback is executed for it. The runtime PM status of a device after - successful execution of the subsystem-level suspend callback is 'suspended'. - - * If the subsystem-level suspend callback returns -EBUSY or -EAGAIN, - the device's runtime PM status is 'active', which means that the device - _must_ be fully operational afterwards. - - * If the subsystem-level suspend callback returns an error code different - from -EBUSY or -EAGAIN, the PM core regards this as a fatal error and will - refuse to run the helper functions described in Section 4 for the device, - until the status of it is directly set either to 'active', or to 'suspended' - (the PM core provides special helper functions for this purpose). - -In particular, if the driver requires remote wake-up capability (i.e. hardware + * Once the subsystem-level suspend callback (or the driver suspend callback, + if invoked directly) has completed successfully for the given device, the PM + core regards the device as suspended, which need not mean that it has been + put into a low power state. It is supposed to mean, however, that the + device will not process data and will not communicate with the CPU(s) and + RAM until the appropriate resume callback is executed for it. The runtime + PM status of a device after successful execution of the suspend callback is + 'suspended'. + + * If the suspend callback returns -EBUSY or -EAGAIN, the device's runtime PM + status remains 'active', which means that the device _must_ be fully + operational afterwards. + + * If the suspend callback returns an error code different from -EBUSY and + -EAGAIN, the PM core regards this as a fatal error and will refuse to run + the helper functions described in Section 4 for the device until its status + is directly set to either'active', or 'suspended' (the PM core provides + special helper functions for this purpose). + +In particular, if the driver requires remote wakeup capability (i.e. hardware mechanism allowing the device to request a change of its power state, such as PCI PME) for proper functioning and device_run_wake() returns 'false' for the device, then ->runtime_suspend() should return -EBUSY. On the other hand, if -device_run_wake() returns 'true' for the device and the device is put into a low -power state during the execution of the subsystem-level suspend callback, it is -expected that remote wake-up will be enabled for the device. Generally, remote -wake-up should be enabled for all input devices put into a low power state at -run time. - -The subsystem-level resume callback is _entirely_ _responsible_ for handling the -resume of the device as appropriate, which may, but need not include executing -the device driver's own ->runtime_resume() callback (from the PM core's point of -view it is not necessary to implement a ->runtime_resume() callback in a device -driver as long as the subsystem-level resume callback knows what to do to handle -the device). - - * Once the subsystem-level resume callback has completed successfully, the PM - core regards the device as fully operational, which means that the device - _must_ be able to complete I/O operations as needed. The runtime PM status - of the device is then 'active'. - - * If the subsystem-level resume callback returns an error code, the PM core - regards this as a fatal error and will refuse to run the helper functions - described in Section 4 for the device, until its status is directly set - either to 'active' or to 'suspended' (the PM core provides special helper - functions for this purpose). - -The subsystem-level idle callback is executed by the PM core whenever the device -appears to be idle, which is indicated to the PM core by two counters, the -device's usage counter and the counter of 'active' children of the device. +device_run_wake() returns 'true' for the device and the device is put into a +low-power state during the execution of the suspend callback, it is expected +that remote wakeup will be enabled for the device. Generally, remote wakeup +should be enabled for all input devices put into low-power states at run time. + +The subsystem-level resume callback, if present, is _entirely_ _responsible_ for +handling the resume of the device as appropriate, which may, but need not +include executing the device driver's own ->runtime_resume() callback (from the +PM core's point of view it is not necessary to implement a ->runtime_resume() +callback in a device driver as long as the subsystem-level resume callback knows +what to do to handle the device). + + * Once the subsystem-level resume callback (or the driver resume callback, if + invoked directly) has completed successfully, the PM core regards the device + as fully operational, which means that the device _must_ be able to complete + I/O operations as needed. The runtime PM status of the device is then + 'active'. + + * If the resume callback returns an error code, the PM core regards this as a + fatal error and will refuse to run the helper functions described in Section + 4 for the device, until its status is directly set to either 'active', or + 'suspended' (by means of special helper functions provided by the PM core + for this purpose). + +The idle callback (a subsystem-level one, if present, or the driver one) is +executed by the PM core whenever the device appears to be idle, which is +indicated to the PM core by two counters, the device's usage counter and the +counter of 'active' children of the device. * If any of these counters is decreased using a helper function provided by the PM core and it turns out to be equal to zero, the other counter is checked. If that counter also is equal to zero, the PM core executes the - subsystem-level idle callback with the device as an argument. + idle callback with the device as its argument. -The action performed by a subsystem-level idle callback is totally dependent on -the subsystem in question, but the expected and recommended action is to check +The action performed by the idle callback is totally dependent on the subsystem +(or driver) in question, but the expected and recommended action is to check if the device can be suspended (i.e. if all of the conditions necessary for suspending the device are satisfied) and to queue up a suspend request for the device in that case. The value returned by this callback is ignored by the PM core. The helper functions provided by the PM core, described in Section 4, guarantee -that the following constraints are met with respect to the bus type's runtime -PM callbacks: +that the following constraints are met with respect to runtime PM callbacks for +one device: (1) The callbacks are mutually exclusive (e.g. it is forbidden to execute ->runtime_suspend() in parallel with ->runtime_resume() or with another diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index b5cef7e7de23..e2cc3d2e0ecc 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -383,10 +383,15 @@ static int device_resume_noirq(struct device *dev, pm_message_t state) info = "EARLY class "; callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - info = "EARLY "; + info = "EARLY bus "; callback = pm_noirq_op(dev->bus->pm, state); } + if (!callback && dev->driver && dev->driver->pm) { + info = "EARLY driver "; + callback = pm_noirq_op(dev->driver->pm, state); + } + error = dpm_run_callback(callback, dev, state, info); TRACE_RESUME(error); @@ -464,20 +469,20 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) if (dev->pm_domain) { info = "power domain "; callback = pm_op(&dev->pm_domain->ops, state); - goto End; + goto Driver; } if (dev->type && dev->type->pm) { info = "type "; callback = pm_op(dev->type->pm, state); - goto End; + goto Driver; } if (dev->class) { if (dev->class->pm) { info = "class "; callback = pm_op(dev->class->pm, state); - goto End; + goto Driver; } else if (dev->class->resume) { info = "legacy class "; callback = dev->class->resume; @@ -487,14 +492,21 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) if (dev->bus) { if (dev->bus->pm) { - info = ""; + info = "bus "; callback = pm_op(dev->bus->pm, state); } else if (dev->bus->resume) { - info = "legacy "; + info = "legacy bus "; callback = dev->bus->resume; + goto End; } } + Driver: + if (!callback && dev->driver && dev->driver->pm) { + info = "driver "; + callback = pm_op(dev->driver->pm, state); + } + End: error = dpm_run_callback(callback, dev, state, info); dev->power.is_suspended = false; @@ -588,24 +600,33 @@ void dpm_resume(pm_message_t state) */ static void device_complete(struct device *dev, pm_message_t state) { + void (*callback)(struct device *) = NULL; + char *info = NULL; + device_lock(dev); if (dev->pm_domain) { - pm_dev_dbg(dev, state, "completing power domain "); - if (dev->pm_domain->ops.complete) - dev->pm_domain->ops.complete(dev); + info = "completing power domain "; + callback = dev->pm_domain->ops.complete; } else if (dev->type && dev->type->pm) { - pm_dev_dbg(dev, state, "completing type "); - if (dev->type->pm->complete) - dev->type->pm->complete(dev); + info = "completing type "; + callback = dev->type->pm->complete; } else if (dev->class && dev->class->pm) { - pm_dev_dbg(dev, state, "completing class "); - if (dev->class->pm->complete) - dev->class->pm->complete(dev); + info = "completing class "; + callback = dev->class->pm->complete; } else if (dev->bus && dev->bus->pm) { - pm_dev_dbg(dev, state, "completing "); - if (dev->bus->pm->complete) - dev->bus->pm->complete(dev); + info = "completing bus "; + callback = dev->bus->pm->complete; + } + + if (!callback && dev->driver && dev->driver->pm) { + info = "completing driver "; + callback = dev->driver->pm->complete; + } + + if (callback) { + pm_dev_dbg(dev, state, info); + callback(dev); } device_unlock(dev); @@ -704,10 +725,15 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state) info = "LATE class "; callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - info = "LATE "; + info = "LATE bus "; callback = pm_noirq_op(dev->bus->pm, state); } + if (!callback && dev->driver && dev->driver->pm) { + info = "LATE driver "; + callback = pm_noirq_op(dev->driver->pm, state); + } + return dpm_run_callback(callback, dev, state, info); } @@ -832,16 +858,21 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) if (dev->bus) { if (dev->bus->pm) { - info = ""; + info = "bus "; callback = pm_op(dev->bus->pm, state); } else if (dev->bus->suspend) { - pm_dev_dbg(dev, state, "legacy "); + pm_dev_dbg(dev, state, "legacy bus "); error = legacy_suspend(dev, state, dev->bus->suspend); goto End; } } Run: + if (!callback && dev->driver && dev->driver->pm) { + info = "driver "; + callback = pm_op(dev->driver->pm, state); + } + error = dpm_run_callback(callback, dev, state, info); End: @@ -949,6 +980,8 @@ int dpm_suspend(pm_message_t state) */ static int device_prepare(struct device *dev, pm_message_t state) { + int (*callback)(struct device *) = NULL; + char *info = NULL; int error = 0; device_lock(dev); @@ -956,25 +989,27 @@ static int device_prepare(struct device *dev, pm_message_t state) dev->power.wakeup_path = device_may_wakeup(dev); if (dev->pm_domain) { - pm_dev_dbg(dev, state, "preparing power domain "); - if (dev->pm_domain->ops.prepare) - error = dev->pm_domain->ops.prepare(dev); - suspend_report_result(dev->pm_domain->ops.prepare, error); + info = "preparing power domain "; + callback = dev->pm_domain->ops.prepare; } 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); - suspend_report_result(dev->type->pm->prepare, error); + info = "preparing type "; + callback = dev->type->pm->prepare; } else if (dev->class && dev->class->pm) { - pm_dev_dbg(dev, state, "preparing class "); - if (dev->class->pm->prepare) - error = dev->class->pm->prepare(dev); - suspend_report_result(dev->class->pm->prepare, error); + info = "preparing class "; + callback = dev->class->pm->prepare; } else if (dev->bus && dev->bus->pm) { - pm_dev_dbg(dev, state, "preparing "); - if (dev->bus->pm->prepare) - error = dev->bus->pm->prepare(dev); - suspend_report_result(dev->bus->pm->prepare, error); + info = "preparing bus "; + callback = dev->bus->pm->prepare; + } + + if (!callback && dev->driver && dev->driver->pm) { + info = "preparing driver "; + callback = dev->driver->pm->prepare; + } + + if (callback) { + error = callback(dev); + suspend_report_result(callback, error); } device_unlock(dev); diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 8c78443bca8f..c56efd756531 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -250,6 +250,9 @@ static int rpm_idle(struct device *dev, int rpmflags) else callback = NULL; + if (!callback && dev->driver && dev->driver->pm) + callback = dev->driver->pm->runtime_idle; + if (callback) __rpm_callback(callback, dev); @@ -413,6 +416,9 @@ static int rpm_suspend(struct device *dev, int rpmflags) else callback = NULL; + if (!callback && dev->driver && dev->driver->pm) + callback = dev->driver->pm->runtime_suspend; + retval = rpm_callback(callback, dev); if (retval) { __update_runtime_status(dev, RPM_ACTIVE); @@ -633,6 +639,9 @@ static int rpm_resume(struct device *dev, int rpmflags) else callback = NULL; + if (!callback && dev->driver && dev->driver->pm) + callback = dev->driver->pm->runtime_resume; + retval = rpm_callback(callback, dev); if (retval) { __update_runtime_status(dev, RPM_SUSPENDED); -- cgit v1.2.3 From 3bb3dbbd56ea39e5537db8f8041ea95d28f16a7f Mon Sep 17 00:00:00 2001 From: Donggeun Kim Date: Tue, 27 Dec 2011 18:47:48 +0900 Subject: power_supply: Add initial Charger-Manager driver Because battery health monitoring should be done even when suspended, it needs to wake up and suspend periodically. Thus, userspace battery monitoring may incur too much overhead; every device and task is woken up periodically. Charger Manager uses suspend-again to provide in-suspend monitoring. This patch allows to monitor battery health in-suspend state. Signed-off-by: Donggeun Kim Signed-off-by: MyungJoo Ham Signed-off-by: Kyungmin Park Signed-off-by: Anton Vorontsov --- Documentation/power/charger-manager.txt | 149 ++++++ drivers/power/Kconfig | 10 + drivers/power/Makefile | 1 + drivers/power/charger-manager.c | 779 ++++++++++++++++++++++++++++++++ include/linux/power/charger-manager.h | 130 ++++++ 5 files changed, 1069 insertions(+) create mode 100644 Documentation/power/charger-manager.txt create mode 100644 drivers/power/charger-manager.c create mode 100644 include/linux/power/charger-manager.h (limited to 'Documentation/power') diff --git a/Documentation/power/charger-manager.txt b/Documentation/power/charger-manager.txt new file mode 100644 index 000000000000..081489f3db25 --- /dev/null +++ b/Documentation/power/charger-manager.txt @@ -0,0 +1,149 @@ +Charger Manager + (C) 2011 MyungJoo Ham , GPL + +Charger Manager provides in-kernel battery charger management that +requires temperature monitoring during suspend-to-RAM state +and where each battery may have multiple chargers attached and the userland +wants to look at the aggregated information of the multiple chargers. + +Charger Manager is a platform_driver with power-supply-class entries. +An instance of Charger Manager (a platform-device created with Charger-Manager) +represents an independent battery with chargers. If there are multiple +batteries with their own chargers acting independently in a system, +the system may need multiple instances of Charger Manager. + +1. Introduction +=============== + +Charger Manager supports the following: + +* Support for multiple chargers (e.g., a device with USB, AC, and solar panels) + A system may have multiple chargers (or power sources) and some of + they may be activated at the same time. Each charger may have its + own power-supply-class and each power-supply-class can provide + different information about the battery status. This framework + aggregates charger-related information from multiple sources and + shows combined information as a single power-supply-class. + +* Support for in suspend-to-RAM polling (with suspend_again callback) + While the battery is being charged and the system is in suspend-to-RAM, + we may need to monitor the battery health by looking at the ambient or + battery temperature. We can accomplish this by waking up the system + periodically. However, such a method wakes up devices unncessary for + monitoring the battery health and tasks, and user processes that are + supposed to be kept suspended. That, in turn, incurs unnecessary power + consumption and slow down charging process. Or even, such peak power + consumption can stop chargers in the middle of charging + (external power input < device power consumption), which not + only affects the charging time, but the lifespan of the battery. + + Charger Manager provides a function "cm_suspend_again" that can be + used as suspend_again callback of platform_suspend_ops. If the platform + requires tasks other than cm_suspend_again, it may implement its own + suspend_again callback that calls cm_suspend_again in the middle. + Normally, the platform will need to resume and suspend some devices + that are used by Charger Manager. + +2. Global Charger-Manager Data related with suspend_again +======================================================== +In order to setup Charger Manager with suspend-again feature +(in-suspend monitoring), the user should provide charger_global_desc +with setup_charger_manager(struct charger_global_desc *). +This charger_global_desc data for in-suspend monitoring is global +as the name suggests. Thus, the user needs to provide only once even +if there are multiple batteries. If there are multiple batteries, the +multiple instances of Charger Manager share the same charger_global_desc +and it will manage in-suspend monitoring for all instances of Charger Manager. + +The user needs to provide all the two entries properly in order to activate +in-suspend monitoring: + +struct charger_global_desc { + +char *rtc_name; + : The name of rtc (e.g., "rtc0") used to wakeup the system from + suspend for Charger Manager. The alarm interrupt (AIE) of the rtc + should be able to wake up the system from suspend. Charger Manager + saves and restores the alarm value and use the previously-defined + alarm if it is going to go off earlier than Charger Manager so that + Charger Manager does not interfere with previously-defined alarms. + +bool (*rtc_only_wakeup)(void); + : This callback should let CM know whether + the wakeup-from-suspend is caused only by the alarm of "rtc" in the + same struct. If there is any other wakeup source triggered the + wakeup, it should return false. If the "rtc" is the only wakeup + reason, it should return true. +}; + +3. How to setup suspend_again +============================= +Charger Manager provides a function "extern bool cm_suspend_again(void)". +When cm_suspend_again is called, it monitors every battery. The suspend_ops +callback of the system's platform_suspend_ops can call cm_suspend_again +function to know whether Charger Manager wants to suspend again or not. +If there are no other devices or tasks that want to use suspend_again +feature, the platform_suspend_ops may directly refer to cm_suspend_again +for its suspend_again callback. + +The cm_suspend_again() returns true (meaning "I want to suspend again") +if the system was woken up by Charger Manager and the polling +(in-suspend monitoring) results in "normal". + +4. Charger-Manager Data (struct charger_desc) +============================================= +For each battery charged independently from other batteries (if a series of +batteries are charged by a single charger, they are counted as one independent +battery), an instance of Charger Manager is attached to it. + +struct charger_desc { + +enum polling_modes polling_mode; + : CM_POLL_DISABLE: do not poll this battery. + CM_POLL_ALWAYS: always poll this battery. + CM_POLL_EXTERNAL_POWER_ONLY: poll this battery if and only if + an external power source is attached. + CM_POLL_CHARGING_ONLY: poll this battery if and only if the + battery is being charged. + +unsigned int polling_interval_ms; + : Required polling interval in ms. Charger Manager will poll + this battery every polling_interval_ms or more frequently. + +enum data_source battery_present; + CM_FUEL_GAUGE: get battery presence information from fuel gauge. + CM_CHARGER_STAT: get battery presence from chargers. + +char **psy_charger_stat; + : An array ending with NULL that has power-supply-class names of + chargers. Each power-supply-class should provide "PRESENT" (if + battery_present is "CM_CHARGER_STAT"), "ONLINE" (shows whether an + external power source is attached or not), and "STATUS" (shows whether + the battery is {"FULL" or not FULL} or {"FULL", "Charging", + "Discharging", "NotCharging"}). + +int num_charger_regulators; +struct regulator_bulk_data *charger_regulators; + : Regulators representing the chargers in the form for + regulator framework's bulk functions. + +char *psy_fuel_gauge; + : Power-supply-class name of the fuel gauge. + +int (*temperature_out_of_range)(int *mC); + : This callback returns 0 if the temperature is safe for charging, + a positive number if it is too hot to charge, and a negative number + if it is too cold to charge. With the variable mC, the callback returns + the temperature in 1/1000 of centigrade. +}; + +5. Other Considerations +======================= + +At the charger/battery-related events such as battery-pulled-out, +charger-pulled-out, charger-inserted, DCIN-over/under-voltage, charger-stopped, +and others critical to chargers, the system should be configured to wake up. +At least the following should wake up the system from a suspend: +a) charger-on/off b) external-power-in/out c) battery-in/out (while charging) + +It is usually accomplished by configuring the PMIC as a wakeup source. diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig index 57de051a74b3..363f4d1ae067 100644 --- a/drivers/power/Kconfig +++ b/drivers/power/Kconfig @@ -235,6 +235,16 @@ config CHARGER_GPIO This driver can be build as a module. If so, the module will be called gpio-charger. +config CHARGER_MANAGER + bool "Battery charger manager for multiple chargers" + depends on REGULATOR && RTC_CLASS + help + Say Y to enable charger-manager support, which allows multiple + chargers attached to a battery and multiple batteries attached to a + system. The charger-manager also can monitor charging status in + runtime and in suspend-to-RAM by waking up the system periodically + with help of suspend_again support. + config CHARGER_MAX8997 tristate "Maxim MAX8997/MAX8966 PMIC battery charger driver" depends on MFD_MAX8997 && REGULATOR_MAX8997 diff --git a/drivers/power/Makefile b/drivers/power/Makefile index b4af13dd8b66..d3b24e99acbe 100644 --- a/drivers/power/Makefile +++ b/drivers/power/Makefile @@ -36,5 +36,6 @@ obj-$(CONFIG_CHARGER_ISP1704) += isp1704_charger.o obj-$(CONFIG_CHARGER_MAX8903) += max8903_charger.o obj-$(CONFIG_CHARGER_TWL4030) += twl4030_charger.o obj-$(CONFIG_CHARGER_GPIO) += gpio-charger.o +obj-$(CONFIG_CHARGER_MANAGER) += charger-manager.o obj-$(CONFIG_CHARGER_MAX8997) += max8997_charger.o obj-$(CONFIG_CHARGER_MAX8998) += max8998_charger.o diff --git a/drivers/power/charger-manager.c b/drivers/power/charger-manager.c new file mode 100644 index 000000000000..727a259ea46c --- /dev/null +++ b/drivers/power/charger-manager.c @@ -0,0 +1,779 @@ +/* + * Copyright (C) 2011 Samsung Electronics Co., Ltd. + * MyungJoo Ham + * + * This driver enables to monitor battery health and control charger + * during suspend-to-mem. + * Charger manager depends on other devices. register this later than + * the depending devices. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +**/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Regard CM_JIFFIES_SMALL jiffies is small enough to ignore for + * delayed works so that we can run delayed works with CM_JIFFIES_SMALL + * without any delays. + */ +#define CM_JIFFIES_SMALL (2) + +/* If y is valid (> 0) and smaller than x, do x = y */ +#define CM_MIN_VALID(x, y) x = (((y > 0) && ((x) > (y))) ? (y) : (x)) + +/* + * Regard CM_RTC_SMALL (sec) is small enough to ignore error in invoking + * rtc alarm. It should be 2 or larger + */ +#define CM_RTC_SMALL (2) + +#define UEVENT_BUF_SIZE 32 + +static LIST_HEAD(cm_list); +static DEFINE_MUTEX(cm_list_mtx); + +/* About in-suspend (suspend-again) monitoring */ +static struct rtc_device *rtc_dev; +/* + * Backup RTC alarm + * Save the wakeup alarm before entering suspend-to-RAM + */ +static struct rtc_wkalrm rtc_wkalarm_save; +/* Backup RTC alarm time in terms of seconds since 01-01-1970 00:00:00 */ +static unsigned long rtc_wkalarm_save_time; +static bool cm_suspended; +static bool cm_rtc_set; +static unsigned long cm_suspend_duration_ms; + +/* Global charger-manager description */ +static struct charger_global_desc *g_desc; /* init with setup_charger_manager */ + +/** + * is_batt_present - See if the battery presents in place. + * @cm: the Charger Manager representing the battery. + */ +static bool is_batt_present(struct charger_manager *cm) +{ + union power_supply_propval val; + bool present = false; + int i, ret; + + switch (cm->desc->battery_present) { + case CM_FUEL_GAUGE: + ret = cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_PRESENT, &val); + if (ret == 0 && val.intval) + present = true; + break; + case CM_CHARGER_STAT: + for (i = 0; cm->charger_stat[i]; i++) { + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_PRESENT, &val); + if (ret == 0 && val.intval) { + present = true; + break; + } + } + break; + } + + return present; +} + +/** + * is_ext_pwr_online - See if an external power source is attached to charge + * @cm: the Charger Manager representing the battery. + * + * Returns true if at least one of the chargers of the battery has an external + * power source attached to charge the battery regardless of whether it is + * actually charging or not. + */ +static bool is_ext_pwr_online(struct charger_manager *cm) +{ + union power_supply_propval val; + bool online = false; + int i, ret; + + /* If at least one of them has one, it's yes. */ + for (i = 0; cm->charger_stat[i]; i++) { + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_ONLINE, &val); + if (ret == 0 && val.intval) { + online = true; + break; + } + } + + return online; +} + +/** + * is_charging - Returns true if the battery is being charged. + * @cm: the Charger Manager representing the battery. + */ +static bool is_charging(struct charger_manager *cm) +{ + int i, ret; + bool charging = false; + union power_supply_propval val; + + /* If there is no battery, it cannot be charged */ + if (!is_batt_present(cm)) + return false; + + /* If at least one of the charger is charging, return yes */ + for (i = 0; cm->charger_stat[i]; i++) { + /* 1. The charger sholuld not be DISABLED */ + if (cm->emergency_stop) + continue; + if (!cm->charger_enabled) + continue; + + /* 2. The charger should be online (ext-power) */ + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_ONLINE, &val); + if (ret) { + dev_warn(cm->dev, "Cannot read ONLINE value from %s.\n", + cm->desc->psy_charger_stat[i]); + continue; + } + if (val.intval == 0) + continue; + + /* + * 3. The charger should not be FULL, DISCHARGING, + * or NOT_CHARGING. + */ + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_STATUS, &val); + if (ret) { + dev_warn(cm->dev, "Cannot read STATUS value from %s.\n", + cm->desc->psy_charger_stat[i]); + continue; + } + if (val.intval == POWER_SUPPLY_STATUS_FULL || + val.intval == POWER_SUPPLY_STATUS_DISCHARGING || + val.intval == POWER_SUPPLY_STATUS_NOT_CHARGING) + continue; + + /* Then, this is charging. */ + charging = true; + break; + } + + return charging; +} + +/** + * is_polling_required - Return true if need to continue polling for this CM. + * @cm: the Charger Manager representing the battery. + */ +static bool is_polling_required(struct charger_manager *cm) +{ + switch (cm->desc->polling_mode) { + case CM_POLL_DISABLE: + return false; + case CM_POLL_ALWAYS: + return true; + case CM_POLL_EXTERNAL_POWER_ONLY: + return is_ext_pwr_online(cm); + case CM_POLL_CHARGING_ONLY: + return is_charging(cm); + default: + dev_warn(cm->dev, "Incorrect polling_mode (%d)\n", + cm->desc->polling_mode); + } + + return false; +} + +/** + * try_charger_enable - Enable/Disable chargers altogether + * @cm: the Charger Manager representing the battery. + * @enable: true: enable / false: disable + * + * Note that Charger Manager keeps the charger enabled regardless whether + * the charger is charging or not (because battery is full or no external + * power source exists) except when CM needs to disable chargers forcibly + * bacause of emergency causes; when the battery is overheated or too cold. + */ +static int try_charger_enable(struct charger_manager *cm, bool enable) +{ + int err = 0, i; + struct charger_desc *desc = cm->desc; + + /* Ignore if it's redundent command */ + if (enable && cm->charger_enabled) + return 0; + if (!enable && !cm->charger_enabled) + return 0; + + if (enable) { + if (cm->emergency_stop) + return -EAGAIN; + err = regulator_bulk_enable(desc->num_charger_regulators, + desc->charger_regulators); + } else { + /* + * Abnormal battery state - Stop charging forcibly, + * even if charger was enabled at the other places + */ + err = regulator_bulk_disable(desc->num_charger_regulators, + desc->charger_regulators); + + for (i = 0; i < desc->num_charger_regulators; i++) { + if (regulator_is_enabled( + desc->charger_regulators[i].consumer)) { + regulator_force_disable( + desc->charger_regulators[i].consumer); + dev_warn(cm->dev, + "Disable regulator(%s) forcibly.\n", + desc->charger_regulators[i].supply); + } + } + } + + if (!err) + cm->charger_enabled = enable; + + return err; +} + +/** + * uevent_notify - Let users know something has changed. + * @cm: the Charger Manager representing the battery. + * @event: the event string. + * + * If @event is null, it implies that uevent_notify is called + * by resume function. When called in the resume function, cm_suspended + * should be already reset to false in order to let uevent_notify + * notify the recent event during the suspend to users. While + * suspended, uevent_notify does not notify users, but tracks + * events so that uevent_notify can notify users later after resumed. + */ +static void uevent_notify(struct charger_manager *cm, const char *event) +{ + static char env_str[UEVENT_BUF_SIZE + 1] = ""; + static char env_str_save[UEVENT_BUF_SIZE + 1] = ""; + + if (cm_suspended) { + /* Nothing in suspended-event buffer */ + if (env_str_save[0] == 0) { + if (!strncmp(env_str, event, UEVENT_BUF_SIZE)) + return; /* status not changed */ + strncpy(env_str_save, event, UEVENT_BUF_SIZE); + return; + } + + if (!strncmp(env_str_save, event, UEVENT_BUF_SIZE)) + return; /* Duplicated. */ + else + strncpy(env_str_save, event, UEVENT_BUF_SIZE); + + return; + } + + if (event == NULL) { + /* No messages pending */ + if (!env_str_save[0]) + return; + + strncpy(env_str, env_str_save, UEVENT_BUF_SIZE); + kobject_uevent(&cm->dev->kobj, KOBJ_CHANGE); + env_str_save[0] = 0; + + return; + } + + /* status not changed */ + if (!strncmp(env_str, event, UEVENT_BUF_SIZE)) + return; + + /* save the status and notify the update */ + strncpy(env_str, event, UEVENT_BUF_SIZE); + kobject_uevent(&cm->dev->kobj, KOBJ_CHANGE); + + dev_info(cm->dev, event); +} + +/** + * _cm_monitor - Monitor the temperature and return true for exceptions. + * @cm: the Charger Manager representing the battery. + * + * Returns true if there is an event to notify for the battery. + * (True if the status of "emergency_stop" changes) + */ +static bool _cm_monitor(struct charger_manager *cm) +{ + struct charger_desc *desc = cm->desc; + int temp = desc->temperature_out_of_range(&cm->last_temp_mC); + + dev_dbg(cm->dev, "monitoring (%2.2d.%3.3dC)\n", + cm->last_temp_mC / 1000, cm->last_temp_mC % 1000); + + /* It has been stopped or charging already */ + if (!!temp == !!cm->emergency_stop) + return false; + + if (temp) { + cm->emergency_stop = temp; + if (!try_charger_enable(cm, false)) { + if (temp > 0) + uevent_notify(cm, "OVERHEAT"); + else + uevent_notify(cm, "COLD"); + } + } else { + cm->emergency_stop = 0; + if (!try_charger_enable(cm, true)) + uevent_notify(cm, "CHARGING"); + } + + return true; +} + +/** + * cm_monitor - Monitor every battery. + * + * Returns true if there is an event to notify from any of the batteries. + * (True if the status of "emergency_stop" changes) + */ +static bool cm_monitor(void) +{ + bool stop = false; + struct charger_manager *cm; + + mutex_lock(&cm_list_mtx); + + list_for_each_entry(cm, &cm_list, entry) + stop = stop || _cm_monitor(cm); + + mutex_unlock(&cm_list_mtx); + + return stop; +} + +/** + * cm_setup_timer - For in-suspend monitoring setup wakeup alarm + * for suspend_again. + * + * Returns true if the alarm is set for Charger Manager to use. + * Returns false if + * cm_setup_timer fails to set an alarm, + * cm_setup_timer does not need to set an alarm for Charger Manager, + * or an alarm previously configured is to be used. + */ +static bool cm_setup_timer(void) +{ + struct charger_manager *cm; + unsigned int wakeup_ms = UINT_MAX; + bool ret = false; + + mutex_lock(&cm_list_mtx); + + list_for_each_entry(cm, &cm_list, entry) { + /* Skip if polling is not required for this CM */ + if (!is_polling_required(cm) && !cm->emergency_stop) + continue; + if (cm->desc->polling_interval_ms == 0) + continue; + CM_MIN_VALID(wakeup_ms, cm->desc->polling_interval_ms); + } + + mutex_unlock(&cm_list_mtx); + + if (wakeup_ms < UINT_MAX && wakeup_ms > 0) { + pr_info("Charger Manager wakeup timer: %u ms.\n", wakeup_ms); + if (rtc_dev) { + struct rtc_wkalrm tmp; + unsigned long time, now; + unsigned long add = DIV_ROUND_UP(wakeup_ms, 1000); + + /* + * Set alarm with the polling interval (wakeup_ms) + * except when rtc_wkalarm_save comes first. + * However, the alarm time should be NOW + + * CM_RTC_SMALL or later. + */ + tmp.enabled = 1; + rtc_read_time(rtc_dev, &tmp.time); + rtc_tm_to_time(&tmp.time, &now); + if (add < CM_RTC_SMALL) + add = CM_RTC_SMALL; + time = now + add; + + ret = true; + + if (rtc_wkalarm_save.enabled && + rtc_wkalarm_save_time && + rtc_wkalarm_save_time < time) { + if (rtc_wkalarm_save_time < now + CM_RTC_SMALL) + time = now + CM_RTC_SMALL; + else + time = rtc_wkalarm_save_time; + + /* The timer is not appointed by CM */ + ret = false; + } + + pr_info("Waking up after %lu secs.\n", + time - now); + + rtc_time_to_tm(time, &tmp.time); + rtc_set_alarm(rtc_dev, &tmp); + cm_suspend_duration_ms += wakeup_ms; + return ret; + } + } + + if (rtc_dev) + rtc_set_alarm(rtc_dev, &rtc_wkalarm_save); + return false; +} + +/** + * cm_suspend_again - Determine whether suspend again or not + * + * Returns true if the system should be suspended again + * Returns false if the system should be woken up + */ +bool cm_suspend_again(void) +{ + struct charger_manager *cm; + bool ret = false; + + if (!g_desc || !g_desc->rtc_only_wakeup || !g_desc->rtc_only_wakeup() || + !cm_rtc_set) + return false; + + if (cm_monitor()) + goto out; + + ret = true; + mutex_lock(&cm_list_mtx); + list_for_each_entry(cm, &cm_list, entry) { + if (cm->status_save_ext_pwr_inserted != is_ext_pwr_online(cm) || + cm->status_save_batt != is_batt_present(cm)) + ret = false; + } + mutex_unlock(&cm_list_mtx); + + cm_rtc_set = cm_setup_timer(); +out: + /* It's about the time when the non-CM appointed timer goes off */ + if (rtc_wkalarm_save.enabled) { + unsigned long now; + struct rtc_time tmp; + + rtc_read_time(rtc_dev, &tmp); + rtc_tm_to_time(&tmp, &now); + + if (rtc_wkalarm_save_time && + now + CM_RTC_SMALL >= rtc_wkalarm_save_time) + return false; + } + return ret; +} +EXPORT_SYMBOL_GPL(cm_suspend_again); + +/** + * setup_charger_manager - initialize charger_global_desc data + * @gd: pointer to instance of charger_global_desc + */ +int setup_charger_manager(struct charger_global_desc *gd) +{ + if (!gd) + return -EINVAL; + + if (rtc_dev) + rtc_class_close(rtc_dev); + rtc_dev = NULL; + g_desc = NULL; + + if (!gd->rtc_only_wakeup) { + pr_err("The callback rtc_only_wakeup is not given.\n"); + return -EINVAL; + } + + if (gd->rtc_name) { + rtc_dev = rtc_class_open(gd->rtc_name); + if (IS_ERR_OR_NULL(rtc_dev)) { + rtc_dev = NULL; + /* Retry at probe. RTC may be not registered yet */ + } + } else { + pr_warn("No wakeup timer is given for charger manager." + "In-suspend monitoring won't work.\n"); + } + + g_desc = gd; + return 0; +} +EXPORT_SYMBOL_GPL(setup_charger_manager); + +static int charger_manager_probe(struct platform_device *pdev) +{ + struct charger_desc *desc = dev_get_platdata(&pdev->dev); + struct charger_manager *cm; + int ret = 0, i = 0; + + if (g_desc && !rtc_dev && g_desc->rtc_name) { + rtc_dev = rtc_class_open(g_desc->rtc_name); + if (IS_ERR_OR_NULL(rtc_dev)) { + rtc_dev = NULL; + dev_err(&pdev->dev, "Cannot get RTC %s.\n", + g_desc->rtc_name); + ret = -ENODEV; + goto err_alloc; + } + } + + if (!desc) { + dev_err(&pdev->dev, "No platform data (desc) found.\n"); + ret = -ENODEV; + goto err_alloc; + } + + cm = kzalloc(sizeof(struct charger_manager), GFP_KERNEL); + if (!cm) { + dev_err(&pdev->dev, "Cannot allocate memory.\n"); + ret = -ENOMEM; + goto err_alloc; + } + + /* Basic Values. Unspecified are Null or 0 */ + cm->dev = &pdev->dev; + cm->desc = kzalloc(sizeof(struct charger_desc), GFP_KERNEL); + if (!cm->desc) { + dev_err(&pdev->dev, "Cannot allocate memory.\n"); + ret = -ENOMEM; + goto err_alloc_desc; + } + memcpy(cm->desc, desc, sizeof(struct charger_desc)); + cm->last_temp_mC = INT_MIN; /* denotes "unmeasured, yet" */ + + if (!desc->charger_regulators || desc->num_charger_regulators < 1) { + ret = -EINVAL; + dev_err(&pdev->dev, "charger_regulators undefined.\n"); + goto err_no_charger; + } + + if (!desc->psy_charger_stat || !desc->psy_charger_stat[0]) { + dev_err(&pdev->dev, "No power supply defined.\n"); + ret = -EINVAL; + goto err_no_charger_stat; + } + + /* Counting index only */ + while (desc->psy_charger_stat[i]) + i++; + + cm->charger_stat = kzalloc(sizeof(struct power_supply *) * (i + 1), + GFP_KERNEL); + if (!cm->charger_stat) { + ret = -ENOMEM; + goto err_no_charger_stat; + } + + for (i = 0; desc->psy_charger_stat[i]; i++) { + cm->charger_stat[i] = power_supply_get_by_name( + desc->psy_charger_stat[i]); + if (!cm->charger_stat[i]) { + dev_err(&pdev->dev, "Cannot find power supply " + "\"%s\"\n", + desc->psy_charger_stat[i]); + ret = -ENODEV; + goto err_chg_stat; + } + } + + cm->fuel_gauge = power_supply_get_by_name(desc->psy_fuel_gauge); + if (!cm->fuel_gauge) { + dev_err(&pdev->dev, "Cannot find power supply \"%s\"\n", + desc->psy_fuel_gauge); + ret = -ENODEV; + goto err_chg_stat; + } + + if (desc->polling_interval_ms == 0 || + msecs_to_jiffies(desc->polling_interval_ms) <= CM_JIFFIES_SMALL) { + dev_err(&pdev->dev, "polling_interval_ms is too small\n"); + ret = -EINVAL; + goto err_chg_stat; + } + + if (!desc->temperature_out_of_range) { + dev_err(&pdev->dev, "there is no temperature_out_of_range\n"); + ret = -EINVAL; + goto err_chg_stat; + } + + platform_set_drvdata(pdev, cm); + + ret = regulator_bulk_get(&pdev->dev, desc->num_charger_regulators, + desc->charger_regulators); + if (ret) { + dev_err(&pdev->dev, "Cannot get charger regulators.\n"); + goto err_chg_stat; + } + + ret = try_charger_enable(cm, true); + if (ret) { + dev_err(&pdev->dev, "Cannot enable charger regulators\n"); + goto err_chg_enable; + } + + /* Add to the list */ + mutex_lock(&cm_list_mtx); + list_add(&cm->entry, &cm_list); + mutex_unlock(&cm_list_mtx); + + return 0; + +err_chg_enable: + if (desc->charger_regulators) + regulator_bulk_free(desc->num_charger_regulators, + desc->charger_regulators); +err_chg_stat: + kfree(cm->charger_stat); +err_no_charger_stat: +err_no_charger: + kfree(cm->desc); +err_alloc_desc: + kfree(cm); +err_alloc: + return ret; +} + +static int __devexit charger_manager_remove(struct platform_device *pdev) +{ + struct charger_manager *cm = platform_get_drvdata(pdev); + struct charger_desc *desc = cm->desc; + + /* Remove from the list */ + mutex_lock(&cm_list_mtx); + list_del(&cm->entry); + mutex_unlock(&cm_list_mtx); + + if (desc->charger_regulators) + regulator_bulk_free(desc->num_charger_regulators, + desc->charger_regulators); + kfree(cm->charger_stat); + kfree(cm->desc); + kfree(cm); + + return 0; +} + +const struct platform_device_id charger_manager_id[] = { + { "charger-manager", 0 }, + { }, +}; + +static int cm_suspend_prepare(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct charger_manager *cm = platform_get_drvdata(pdev); + + if (!cm_suspended) { + if (rtc_dev) { + struct rtc_time tmp; + unsigned long now; + + rtc_read_alarm(rtc_dev, &rtc_wkalarm_save); + rtc_read_time(rtc_dev, &tmp); + + if (rtc_wkalarm_save.enabled) { + rtc_tm_to_time(&rtc_wkalarm_save.time, + &rtc_wkalarm_save_time); + rtc_tm_to_time(&tmp, &now); + if (now > rtc_wkalarm_save_time) + rtc_wkalarm_save_time = 0; + } else { + rtc_wkalarm_save_time = 0; + } + } + cm_suspended = true; + } + + cm->status_save_ext_pwr_inserted = is_ext_pwr_online(cm); + cm->status_save_batt = is_batt_present(cm); + + if (!cm_rtc_set) { + cm_suspend_duration_ms = 0; + cm_rtc_set = cm_setup_timer(); + } + + return 0; +} + +static void cm_suspend_complete(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct charger_manager *cm = platform_get_drvdata(pdev); + + if (cm_suspended) { + if (rtc_dev) { + struct rtc_wkalrm tmp; + + rtc_read_alarm(rtc_dev, &tmp); + rtc_wkalarm_save.pending = tmp.pending; + rtc_set_alarm(rtc_dev, &rtc_wkalarm_save); + } + cm_suspended = false; + cm_rtc_set = false; + } + + uevent_notify(cm, NULL); +} + +static const struct dev_pm_ops charger_manager_pm = { + .prepare = cm_suspend_prepare, + .complete = cm_suspend_complete, +}; + +static struct platform_driver charger_manager_driver = { + .driver = { + .name = "charger-manager", + .owner = THIS_MODULE, + .pm = &charger_manager_pm, + }, + .probe = charger_manager_probe, + .remove = __devexit_p(charger_manager_remove), + .id_table = charger_manager_id, +}; + +static int __init charger_manager_init(void) +{ + return platform_driver_register(&charger_manager_driver); +} +late_initcall(charger_manager_init); + +static void __exit charger_manager_cleanup(void) +{ + platform_driver_unregister(&charger_manager_driver); +} +module_exit(charger_manager_cleanup); + +MODULE_AUTHOR("MyungJoo Ham "); +MODULE_DESCRIPTION("Charger Manager"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("charger-manager"); diff --git a/include/linux/power/charger-manager.h b/include/linux/power/charger-manager.h new file mode 100644 index 000000000000..102c5b3f3325 --- /dev/null +++ b/include/linux/power/charger-manager.h @@ -0,0 +1,130 @@ +/* + * Copyright (C) 2011 Samsung Electronics Co., Ltd. + * MyungJoo.Ham + * + * Charger Manager. + * This framework enables to control and multiple chargers and to + * monitor charging even in the context of suspend-to-RAM with + * an interface combining the chargers. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +**/ + +#ifndef _CHARGER_MANAGER_H +#define _CHARGER_MANAGER_H + +#include + +enum data_source { + CM_FUEL_GAUGE, + CM_CHARGER_STAT, +}; + +enum polling_modes { + CM_POLL_DISABLE = 0, + CM_POLL_ALWAYS, + CM_POLL_EXTERNAL_POWER_ONLY, + CM_POLL_CHARGING_ONLY, +}; + +/** + * struct charger_global_desc + * @rtc_name: the name of RTC used to wake up the system from suspend. + * @rtc_only_wakeup: + * If the system is woken up by waekup-sources other than the RTC or + * callbacks, Charger Manager should recognize with + * rtc_only_wakeup() returning false. + * If the RTC given to CM is the only wakeup reason, + * rtc_only_wakeup should return true. + */ +struct charger_global_desc { + char *rtc_name; + + bool (*rtc_only_wakeup)(void); +}; + +/** + * struct charger_desc + * @polling_mode: + * Determine which polling mode will be used + * @polling_interval_ms: interval in millisecond at which + * charger manager will monitor battery health + * @battery_present: + * Specify where information for existance of battery can be obtained + * @psy_charger_stat: the names of power-supply for chargers + * @num_charger_regulator: the number of entries in charger_regulators + * @charger_regulators: array of regulator_bulk_data for chargers + * @psy_fuel_gauge: the name of power-supply for fuel gauge + * @temperature_out_of_range: + * Determine whether the status is overheat or cold or normal. + * return_value > 0: overheat + * return_value == 0: normal + * return_value < 0: cold + */ +struct charger_desc { + enum polling_modes polling_mode; + unsigned int polling_interval_ms; + + enum data_source battery_present; + + char **psy_charger_stat; + + int num_charger_regulators; + struct regulator_bulk_data *charger_regulators; + + char *psy_fuel_gauge; + + int (*temperature_out_of_range)(int *mC); +}; + +#define PSY_NAME_MAX 30 + +/** + * struct charger_manager + * @entry: entry for list + * @dev: device pointer + * @desc: instance of charger_desc + * @fuel_gauge: power_supply for fuel gauge + * @charger_stat: array of power_supply for chargers + * @charger_enabled: the state of charger + * @emergency_stop: + * When setting true, stop charging + * @last_temp_mC: the measured temperature in milli-Celsius + * @status_save_ext_pwr_inserted: + * saved status of external power before entering suspend-to-RAM + * @status_save_batt: + * saved status of battery before entering suspend-to-RAM + */ +struct charger_manager { + struct list_head entry; + struct device *dev; + struct charger_desc *desc; + + struct power_supply *fuel_gauge; + struct power_supply **charger_stat; + + bool charger_enabled; + + int emergency_stop; + int last_temp_mC; + + bool status_save_ext_pwr_inserted; + bool status_save_batt; +}; + +#ifdef CONFIG_CHARGER_MANAGER +extern int setup_charger_manager(struct charger_global_desc *gd); +extern bool cm_suspend_again(void); +#else +static void __maybe_unused setup_charger_manager(struct charger_global_desc *gd) +{ } + +static bool __maybe_unused cm_suspend_again(void) +{ + return false; +} +#endif + +#endif /* _CHARGER_MANAGER_H */ -- cgit v1.2.3 From ad3d13eee78ec44194bf919a37e2f711e53cbdf0 Mon Sep 17 00:00:00 2001 From: Donggeun Kim Date: Tue, 27 Dec 2011 18:47:49 +0900 Subject: power_supply: Charger-Manager: Add properties for power-supply-class Charger Manager provides power-supply-class aggregating information from multiple chargers and a fuel-gauge. Signed-off-by: Donggeun Kim Signed-off-by: MyungJoo Ham Signed-off-by: Kyungmin Park Signed-off-by: Anton Vorontsov --- Documentation/power/charger-manager.txt | 14 ++ drivers/power/charger-manager.c | 295 +++++++++++++++++++++++++++++++- include/linux/power/charger-manager.h | 17 ++ 3 files changed, 325 insertions(+), 1 deletion(-) (limited to 'Documentation/power') diff --git a/Documentation/power/charger-manager.txt b/Documentation/power/charger-manager.txt index 081489f3db25..fdcca991df30 100644 --- a/Documentation/power/charger-manager.txt +++ b/Documentation/power/charger-manager.txt @@ -98,6 +98,11 @@ battery), an instance of Charger Manager is attached to it. struct charger_desc { +char *psy_name; + : The power-supply-class name of the battery. Default is + "battery" if psy_name is NULL. Users can access the psy entries + at "/sys/class/power_supply/[psy_name]/". + enum polling_modes polling_mode; : CM_POLL_DISABLE: do not poll this battery. CM_POLL_ALWAYS: always poll this battery. @@ -106,6 +111,12 @@ enum polling_modes polling_mode; CM_POLL_CHARGING_ONLY: poll this battery if and only if the battery is being charged. +unsigned int fullbatt_uV; + : If specified with a non-zero value, Charger Manager assumes + that the battery is full (capacity = 100) if the battery is not being + charged and the battery voltage is equal to or greater than + fullbatt_uV. + unsigned int polling_interval_ms; : Required polling interval in ms. Charger Manager will poll this battery every polling_interval_ms or more frequently. @@ -131,10 +142,13 @@ char *psy_fuel_gauge; : Power-supply-class name of the fuel gauge. int (*temperature_out_of_range)(int *mC); +bool measure_battery_temp; : This callback returns 0 if the temperature is safe for charging, a positive number if it is too hot to charge, and a negative number if it is too cold to charge. With the variable mC, the callback returns the temperature in 1/1000 of centigrade. + The source of temperature can be battery or ambient one according to + the value of measure_battery_temp. }; 5. Other Considerations diff --git a/drivers/power/charger-manager.c b/drivers/power/charger-manager.c index 727a259ea46c..0378d019efae 100644 --- a/drivers/power/charger-manager.c +++ b/drivers/power/charger-manager.c @@ -121,6 +121,32 @@ static bool is_ext_pwr_online(struct charger_manager *cm) return online; } +/** + * get_batt_uV - Get the voltage level of the battery + * @cm: the Charger Manager representing the battery. + * @uV: the voltage level returned. + * + * Returns 0 if there is no error. + * Returns a negative value on error. + */ +static int get_batt_uV(struct charger_manager *cm, int *uV) +{ + union power_supply_propval val; + int ret; + + if (cm->fuel_gauge) + ret = cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_VOLTAGE_NOW, &val); + else + return -ENODEV; + + if (ret) + return ret; + + *uV = val.intval; + return 0; +} + /** * is_charging - Returns true if the battery is being charged. * @cm: the Charger Manager representing the battery. @@ -369,6 +395,208 @@ static bool cm_monitor(void) return stop; } +static int charger_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct charger_manager *cm = container_of(psy, + struct charger_manager, charger_psy); + struct charger_desc *desc = cm->desc; + int i, ret = 0, uV; + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + if (is_charging(cm)) + val->intval = POWER_SUPPLY_STATUS_CHARGING; + else if (is_ext_pwr_online(cm)) + val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; + else + val->intval = POWER_SUPPLY_STATUS_DISCHARGING; + break; + case POWER_SUPPLY_PROP_HEALTH: + if (cm->emergency_stop > 0) + val->intval = POWER_SUPPLY_HEALTH_OVERHEAT; + else if (cm->emergency_stop < 0) + val->intval = POWER_SUPPLY_HEALTH_COLD; + else + val->intval = POWER_SUPPLY_HEALTH_GOOD; + break; + case POWER_SUPPLY_PROP_PRESENT: + if (is_batt_present(cm)) + val->intval = 1; + else + val->intval = 0; + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + ret = get_batt_uV(cm, &i); + val->intval = i; + break; + case POWER_SUPPLY_PROP_CURRENT_NOW: + ret = cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_CURRENT_NOW, val); + break; + case POWER_SUPPLY_PROP_TEMP: + /* in thenth of centigrade */ + if (cm->last_temp_mC == INT_MIN) + desc->temperature_out_of_range(&cm->last_temp_mC); + val->intval = cm->last_temp_mC / 100; + if (!desc->measure_battery_temp) + ret = -ENODEV; + break; + case POWER_SUPPLY_PROP_TEMP_AMBIENT: + /* in thenth of centigrade */ + if (cm->last_temp_mC == INT_MIN) + desc->temperature_out_of_range(&cm->last_temp_mC); + val->intval = cm->last_temp_mC / 100; + if (desc->measure_battery_temp) + ret = -ENODEV; + break; + case POWER_SUPPLY_PROP_CAPACITY: + if (!cm->fuel_gauge) { + ret = -ENODEV; + break; + } + + if (!is_batt_present(cm)) { + /* There is no battery. Assume 100% */ + val->intval = 100; + break; + } + + ret = cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_CAPACITY, val); + if (ret) + break; + + if (val->intval > 100) { + val->intval = 100; + break; + } + if (val->intval < 0) + val->intval = 0; + + /* Do not adjust SOC when charging: voltage is overrated */ + if (is_charging(cm)) + break; + + /* + * If the capacity value is inconsistent, calibrate it base on + * the battery voltage values and the thresholds given as desc + */ + ret = get_batt_uV(cm, &uV); + if (ret) { + /* Voltage information not available. No calibration */ + ret = 0; + break; + } + + if (desc->fullbatt_uV > 0 && uV >= desc->fullbatt_uV && + !is_charging(cm)) { + val->intval = 100; + break; + } + + break; + case POWER_SUPPLY_PROP_ONLINE: + if (is_ext_pwr_online(cm)) + val->intval = 1; + else + val->intval = 0; + break; + case POWER_SUPPLY_PROP_CHARGE_FULL: + if (cm->fuel_gauge) { + if (cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_CHARGE_FULL, val) == 0) + break; + } + + if (is_ext_pwr_online(cm)) { + /* Not full if it's charging. */ + if (is_charging(cm)) { + val->intval = 0; + break; + } + /* + * Full if it's powered but not charging andi + * not forced stop by emergency + */ + if (!cm->emergency_stop) { + val->intval = 1; + break; + } + } + + /* Full if it's over the fullbatt voltage */ + ret = get_batt_uV(cm, &uV); + if (!ret && desc->fullbatt_uV > 0 && uV >= desc->fullbatt_uV && + !is_charging(cm)) { + val->intval = 1; + break; + } + + /* Full if the cap is 100 */ + if (cm->fuel_gauge) { + ret = cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_CAPACITY, val); + if (!ret && val->intval >= 100 && !is_charging(cm)) { + val->intval = 1; + break; + } + } + + val->intval = 0; + ret = 0; + break; + case POWER_SUPPLY_PROP_CHARGE_NOW: + if (is_charging(cm)) { + ret = cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_CHARGE_NOW, + val); + if (ret) { + val->intval = 1; + ret = 0; + } else { + /* If CHARGE_NOW is supplied, use it */ + val->intval = (val->intval > 0) ? + val->intval : 1; + } + } else { + val->intval = 0; + } + break; + default: + return -EINVAL; + } + return ret; +} + +#define NUM_CHARGER_PSY_OPTIONAL (4) +static enum power_supply_property default_charger_props[] = { + /* Guaranteed to provide */ + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_HEALTH, + POWER_SUPPLY_PROP_PRESENT, + POWER_SUPPLY_PROP_VOLTAGE_NOW, + POWER_SUPPLY_PROP_CAPACITY, + POWER_SUPPLY_PROP_ONLINE, + POWER_SUPPLY_PROP_CHARGE_FULL, + /* + * Optional properties are: + * POWER_SUPPLY_PROP_CHARGE_NOW, + * POWER_SUPPLY_PROP_CURRENT_NOW, + * POWER_SUPPLY_PROP_TEMP, and + * POWER_SUPPLY_PROP_TEMP_AMBIENT, + */ +}; + +static struct power_supply psy_default = { + .name = "battery", + .type = POWER_SUPPLY_TYPE_BATTERY, + .properties = default_charger_props, + .num_properties = ARRAY_SIZE(default_charger_props), + .get_property = charger_get_property, +}; + /** * cm_setup_timer - For in-suspend monitoring setup wakeup alarm * for suspend_again. @@ -532,6 +760,7 @@ static int charger_manager_probe(struct platform_device *pdev) struct charger_desc *desc = dev_get_platdata(&pdev->dev); struct charger_manager *cm; int ret = 0, i = 0; + union power_supply_propval val; if (g_desc && !rtc_dev && g_desc->rtc_name) { rtc_dev = rtc_class_open(g_desc->rtc_name); @@ -626,11 +855,68 @@ static int charger_manager_probe(struct platform_device *pdev) platform_set_drvdata(pdev, cm); + memcpy(&cm->charger_psy, &psy_default, + sizeof(psy_default)); + if (!desc->psy_name) { + strncpy(cm->psy_name_buf, psy_default.name, + PSY_NAME_MAX); + } else { + strncpy(cm->psy_name_buf, desc->psy_name, PSY_NAME_MAX); + } + cm->charger_psy.name = cm->psy_name_buf; + + /* Allocate for psy properties because they may vary */ + cm->charger_psy.properties = kzalloc(sizeof(enum power_supply_property) + * (ARRAY_SIZE(default_charger_props) + + NUM_CHARGER_PSY_OPTIONAL), + GFP_KERNEL); + if (!cm->charger_psy.properties) { + dev_err(&pdev->dev, "Cannot allocate for psy properties.\n"); + ret = -ENOMEM; + goto err_chg_stat; + } + memcpy(cm->charger_psy.properties, default_charger_props, + sizeof(enum power_supply_property) * + ARRAY_SIZE(default_charger_props)); + cm->charger_psy.num_properties = psy_default.num_properties; + + /* Find which optional psy-properties are available */ + if (!cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_CHARGE_NOW, &val)) { + cm->charger_psy.properties[cm->charger_psy.num_properties] = + POWER_SUPPLY_PROP_CHARGE_NOW; + cm->charger_psy.num_properties++; + } + if (!cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_CURRENT_NOW, + &val)) { + cm->charger_psy.properties[cm->charger_psy.num_properties] = + POWER_SUPPLY_PROP_CURRENT_NOW; + cm->charger_psy.num_properties++; + } + if (!desc->measure_battery_temp) { + cm->charger_psy.properties[cm->charger_psy.num_properties] = + POWER_SUPPLY_PROP_TEMP_AMBIENT; + cm->charger_psy.num_properties++; + } + if (desc->measure_battery_temp) { + cm->charger_psy.properties[cm->charger_psy.num_properties] = + POWER_SUPPLY_PROP_TEMP; + cm->charger_psy.num_properties++; + } + + ret = power_supply_register(NULL, &cm->charger_psy); + if (ret) { + dev_err(&pdev->dev, "Cannot register charger-manager with" + " name \"%s\".\n", cm->charger_psy.name); + goto err_register; + } + ret = regulator_bulk_get(&pdev->dev, desc->num_charger_regulators, desc->charger_regulators); if (ret) { dev_err(&pdev->dev, "Cannot get charger regulators.\n"); - goto err_chg_stat; + goto err_bulk_get; } ret = try_charger_enable(cm, true); @@ -650,6 +936,10 @@ err_chg_enable: if (desc->charger_regulators) regulator_bulk_free(desc->num_charger_regulators, desc->charger_regulators); +err_bulk_get: + power_supply_unregister(&cm->charger_psy); +err_register: + kfree(cm->charger_psy.properties); err_chg_stat: kfree(cm->charger_stat); err_no_charger_stat: @@ -674,6 +964,9 @@ static int __devexit charger_manager_remove(struct platform_device *pdev) if (desc->charger_regulators) regulator_bulk_free(desc->num_charger_regulators, desc->charger_regulators); + + power_supply_unregister(&cm->charger_psy); + kfree(cm->charger_psy.properties); kfree(cm->charger_stat); kfree(cm->desc); kfree(cm); diff --git a/include/linux/power/charger-manager.h b/include/linux/power/charger-manager.h index 102c5b3f3325..4f75e531c112 100644 --- a/include/linux/power/charger-manager.h +++ b/include/linux/power/charger-manager.h @@ -47,8 +47,12 @@ struct charger_global_desc { /** * struct charger_desc + * @psy_name: the name of power-supply-class for charger manager * @polling_mode: * Determine which polling mode will be used + * @fullbatt_uV: voltage in microvolt + * If it is not being charged and VBATT >= fullbatt_uV, + * it is assumed to be full. * @polling_interval_ms: interval in millisecond at which * charger manager will monitor battery health * @battery_present: @@ -62,11 +66,18 @@ struct charger_global_desc { * return_value > 0: overheat * return_value == 0: normal * return_value < 0: cold + * @measure_battery_temp: + * true: measure battery temperature + * false: measure ambient temperature */ struct charger_desc { + char *psy_name; + enum polling_modes polling_mode; unsigned int polling_interval_ms; + unsigned int fullbatt_uV; + enum data_source battery_present; char **psy_charger_stat; @@ -77,6 +88,7 @@ struct charger_desc { char *psy_fuel_gauge; int (*temperature_out_of_range)(int *mC); + bool measure_battery_temp; }; #define PSY_NAME_MAX 30 @@ -92,6 +104,8 @@ struct charger_desc { * @emergency_stop: * When setting true, stop charging * @last_temp_mC: the measured temperature in milli-Celsius + * @psy_name_buf: the name of power-supply-class for charger manager + * @charger_psy: power_supply for charger manager * @status_save_ext_pwr_inserted: * saved status of external power before entering suspend-to-RAM * @status_save_batt: @@ -110,6 +124,9 @@ struct charger_manager { int emergency_stop; int last_temp_mC; + char psy_name_buf[PSY_NAME_MAX + 1]; + struct power_supply charger_psy; + bool status_save_ext_pwr_inserted; bool status_save_batt; }; -- cgit v1.2.3