Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Rafael J. Wysocki | 1226 | 47.76% | 13 | 35.14% |
Nico Pitre | 474 | 18.47% | 1 | 2.70% |
Jon Hunter | 381 | 14.84% | 2 | 5.41% |
Rajendra Nayak | 130 | 5.06% | 1 | 2.70% |
Geert Uytterhoeven | 103 | 4.01% | 3 | 8.11% |
Paul Gortmaker | 68 | 2.65% | 2 | 5.41% |
Dmitry Eremin-Solenikov | 57 | 2.22% | 1 | 2.70% |
Ben Dooks | 53 | 2.06% | 2 | 5.41% |
Grygorii Strashko | 25 | 0.97% | 1 | 2.70% |
Aditya Pakki | 19 | 0.74% | 1 | 2.70% |
Tomeu Vizoso | 11 | 0.43% | 1 | 2.70% |
Magnus Damm | 5 | 0.19% | 1 | 2.70% |
Kefeng Wang | 4 | 0.16% | 1 | 2.70% |
Andy Shevchenko | 3 | 0.12% | 1 | 2.70% |
Greg Kroah-Hartman | 2 | 0.08% | 1 | 2.70% |
Colin Ian King | 2 | 0.08% | 2 | 5.41% |
Murali Karicheri | 2 | 0.08% | 1 | 2.70% |
Pierre-Louis Bossart | 1 | 0.04% | 1 | 2.70% |
Stephen Boyd | 1 | 0.04% | 1 | 2.70% |
Total | 2567 | 37 |
// SPDX-License-Identifier: GPL-2.0 /* * drivers/base/power/clock_ops.c - Generic clock manipulation PM callbacks * * Copyright (c) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp. */ #include <linux/kernel.h> #include <linux/device.h> #include <linux/io.h> #include <linux/pm.h> #include <linux/pm_clock.h> #include <linux/clk.h> #include <linux/clkdev.h> #include <linux/of_clk.h> #include <linux/slab.h> #include <linux/err.h> #include <linux/pm_domain.h> #include <linux/pm_runtime.h> #ifdef CONFIG_PM_CLK enum pce_status { PCE_STATUS_NONE = 0, PCE_STATUS_ACQUIRED, PCE_STATUS_PREPARED, PCE_STATUS_ENABLED, PCE_STATUS_ERROR, }; struct pm_clock_entry { struct list_head node; char *con_id; struct clk *clk; enum pce_status status; bool enabled_when_prepared; }; /** * pm_clk_list_lock - ensure exclusive access for modifying the PM clock * entry list. * @psd: pm_subsys_data instance corresponding to the PM clock entry list * and clk_op_might_sleep count to be modified. * * Get exclusive access before modifying the PM clock entry list and the * clock_op_might_sleep count to guard against concurrent modifications. * This also protects against a concurrent clock_op_might_sleep and PM clock * entry list usage in pm_clk_suspend()/pm_clk_resume() that may or may not * happen in atomic context, hence both the mutex and the spinlock must be * taken here. */ static void pm_clk_list_lock(struct pm_subsys_data *psd) __acquires(&psd->lock) { mutex_lock(&psd->clock_mutex); spin_lock_irq(&psd->lock); } /** * pm_clk_list_unlock - counterpart to pm_clk_list_lock(). * @psd: the same pm_subsys_data instance previously passed to * pm_clk_list_lock(). */ static void pm_clk_list_unlock(struct pm_subsys_data *psd) __releases(&psd->lock) { spin_unlock_irq(&psd->lock); mutex_unlock(&psd->clock_mutex); } /** * pm_clk_op_lock - ensure exclusive access for performing clock operations. * @psd: pm_subsys_data instance corresponding to the PM clock entry list * and clk_op_might_sleep count being used. * @flags: stored irq flags. * @fn: string for the caller function's name. * * This is used by pm_clk_suspend() and pm_clk_resume() to guard * against concurrent modifications to the clock entry list and the * clock_op_might_sleep count. If clock_op_might_sleep is != 0 then * only the mutex can be locked and those functions can only be used in * non atomic context. If clock_op_might_sleep == 0 then these functions * may be used in any context and only the spinlock can be locked. * Returns -EINVAL if called in atomic context when clock ops might sleep. */ static int pm_clk_op_lock(struct pm_subsys_data *psd, unsigned long *flags, const char *fn) /* sparse annotations don't work here as exit state isn't static */ { bool atomic_context = in_atomic() || irqs_disabled(); try_again: spin_lock_irqsave(&psd->lock, *flags); if (!psd->clock_op_might_sleep) { /* the __release is there to work around sparse limitations */ __release(&psd->lock); return 0; } /* bail out if in atomic context */ if (atomic_context) { pr_err("%s: atomic context with clock_ops_might_sleep = %d", fn, psd->clock_op_might_sleep); spin_unlock_irqrestore(&psd->lock, *flags); might_sleep(); return -EPERM; } /* we must switch to the mutex */ spin_unlock_irqrestore(&psd->lock, *flags); mutex_lock(&psd->clock_mutex); /* * There was a possibility for psd->clock_op_might_sleep * to become 0 above. Keep the mutex only if not the case. */ if (likely(psd->clock_op_might_sleep)) return 0; mutex_unlock(&psd->clock_mutex); goto try_again; } /** * pm_clk_op_unlock - counterpart to pm_clk_op_lock(). * @psd: the same pm_subsys_data instance previously passed to * pm_clk_op_lock(). * @flags: irq flags provided by pm_clk_op_lock(). */ static void pm_clk_op_unlock(struct pm_subsys_data *psd, unsigned long *flags) /* sparse annotations don't work here as entry state isn't static */ { if (psd->clock_op_might_sleep) { mutex_unlock(&psd->clock_mutex); } else { /* the __acquire is there to work around sparse limitations */ __acquire(&psd->lock); spin_unlock_irqrestore(&psd->lock, *flags); } } /** * __pm_clk_enable - Enable a clock, reporting any errors * @dev: The device for the given clock * @ce: PM clock entry corresponding to the clock. */ static inline void __pm_clk_enable(struct device *dev, struct pm_clock_entry *ce) { int ret; switch (ce->status) { case PCE_STATUS_ACQUIRED: ret = clk_prepare_enable(ce->clk); break; case PCE_STATUS_PREPARED: ret = clk_enable(ce->clk); break; default: return; } if (!ret) ce->status = PCE_STATUS_ENABLED; else dev_err(dev, "%s: failed to enable clk %p, error %d\n", __func__, ce->clk, ret); } /** * pm_clk_acquire - Acquire a device clock. * @dev: Device whose clock is to be acquired. * @ce: PM clock entry corresponding to the clock. */ static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) { if (!ce->clk) ce->clk = clk_get(dev, ce->con_id); if (IS_ERR(ce->clk)) { ce->status = PCE_STATUS_ERROR; return; } else if (clk_is_enabled_when_prepared(ce->clk)) { /* we defer preparing the clock in that case */ ce->status = PCE_STATUS_ACQUIRED; ce->enabled_when_prepared = true; } else if (clk_prepare(ce->clk)) { ce->status = PCE_STATUS_ERROR; dev_err(dev, "clk_prepare() failed\n"); return; } else { ce->status = PCE_STATUS_PREPARED; } dev_dbg(dev, "Clock %pC con_id %s managed by runtime PM.\n", ce->clk, ce->con_id); } static int __pm_clk_add(struct device *dev, const char *con_id, struct clk *clk) { struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; if (!psd) return -EINVAL; ce = kzalloc(sizeof(*ce), GFP_KERNEL); if (!ce) return -ENOMEM; if (con_id) { ce->con_id = kstrdup(con_id, GFP_KERNEL); if (!ce->con_id) { kfree(ce); return -ENOMEM; } } else { if (IS_ERR(clk)) { kfree(ce); return -ENOENT; } ce->clk = clk; } pm_clk_acquire(dev, ce); pm_clk_list_lock(psd); list_add_tail(&ce->node, &psd->clock_list); if (ce->enabled_when_prepared) psd->clock_op_might_sleep++; pm_clk_list_unlock(psd); return 0; } /** * pm_clk_add - Start using a device clock for power management. * @dev: Device whose clock is going to be used for power management. * @con_id: Connection ID of the clock. * * Add the clock represented by @con_id to the list of clocks used for * the power management of @dev. */ int pm_clk_add(struct device *dev, const char *con_id) { return __pm_clk_add(dev, con_id, NULL); } EXPORT_SYMBOL_GPL(pm_clk_add); /** * pm_clk_add_clk - Start using a device clock for power management. * @dev: Device whose clock is going to be used for power management. * @clk: Clock pointer * * Add the clock to the list of clocks used for the power management of @dev. * The power-management code will take control of the clock reference, so * callers should not call clk_put() on @clk after this function sucessfully * returned. */ int pm_clk_add_clk(struct device *dev, struct clk *clk) { return __pm_clk_add(dev, NULL, clk); } EXPORT_SYMBOL_GPL(pm_clk_add_clk); /** * of_pm_clk_add_clk - Start using a device clock for power management. * @dev: Device whose clock is going to be used for power management. * @name: Name of clock that is going to be used for power management. * * Add the clock described in the 'clocks' device-tree node that matches * with the 'name' provided, to the list of clocks used for the power * management of @dev. On success, returns 0. Returns a negative error * code if the clock is not found or cannot be added. */ int of_pm_clk_add_clk(struct device *dev, const char *name) { struct clk *clk; int ret; if (!dev || !dev->of_node || !name) return -EINVAL; clk = of_clk_get_by_name(dev->of_node, name); if (IS_ERR(clk)) return PTR_ERR(clk); ret = pm_clk_add_clk(dev, clk); if (ret) { clk_put(clk); return ret; } return 0; } EXPORT_SYMBOL_GPL(of_pm_clk_add_clk); /** * of_pm_clk_add_clks - Start using device clock(s) for power management. * @dev: Device whose clock(s) is going to be used for power management. * * Add a series of clocks described in the 'clocks' device-tree node for * a device to the list of clocks used for the power management of @dev. * On success, returns the number of clocks added. Returns a negative * error code if there are no clocks in the device node for the device * or if adding a clock fails. */ int of_pm_clk_add_clks(struct device *dev) { struct clk **clks; int i, count; int ret; if (!dev || !dev->of_node) return -EINVAL; count = of_clk_get_parent_count(dev->of_node); if (count <= 0) return -ENODEV; clks = kcalloc(count, sizeof(*clks), GFP_KERNEL); if (!clks) return -ENOMEM; for (i = 0; i < count; i++) { clks[i] = of_clk_get(dev->of_node, i); if (IS_ERR(clks[i])) { ret = PTR_ERR(clks[i]); goto error; } ret = pm_clk_add_clk(dev, clks[i]); if (ret) { clk_put(clks[i]); goto error; } } kfree(clks); return i; error: while (i--) pm_clk_remove_clk(dev, clks[i]); kfree(clks); return ret; } EXPORT_SYMBOL_GPL(of_pm_clk_add_clks); /** * __pm_clk_remove - Destroy PM clock entry. * @ce: PM clock entry to destroy. */ static void __pm_clk_remove(struct pm_clock_entry *ce) { if (!ce) return; switch (ce->status) { case PCE_STATUS_ENABLED: clk_disable(ce->clk); fallthrough; case PCE_STATUS_PREPARED: clk_unprepare(ce->clk); fallthrough; case PCE_STATUS_ACQUIRED: case PCE_STATUS_ERROR: if (!IS_ERR(ce->clk)) clk_put(ce->clk); break; default: break; } kfree(ce->con_id); kfree(ce); } /** * pm_clk_remove - Stop using a device clock for power management. * @dev: Device whose clock should not be used for 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 power management of @dev. */ void pm_clk_remove(struct device *dev, const char *con_id) { struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; if (!psd) return; pm_clk_list_lock(psd); list_for_each_entry(ce, &psd->clock_list, node) { if (!con_id && !ce->con_id) goto remove; else if (!con_id || !ce->con_id) continue; else if (!strcmp(con_id, ce->con_id)) goto remove; } pm_clk_list_unlock(psd); return; remove: list_del(&ce->node); if (ce->enabled_when_prepared) psd->clock_op_might_sleep--; pm_clk_list_unlock(psd); __pm_clk_remove(ce); } EXPORT_SYMBOL_GPL(pm_clk_remove); /** * pm_clk_remove_clk - Stop using a device clock for power management. * @dev: Device whose clock should not be used for PM any more. * @clk: Clock pointer * * Remove the clock pointed to by @clk from the list of clocks used for * the power management of @dev. */ void pm_clk_remove_clk(struct device *dev, struct clk *clk) { struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; if (!psd || !clk) return; pm_clk_list_lock(psd); list_for_each_entry(ce, &psd->clock_list, node) { if (clk == ce->clk) goto remove; } pm_clk_list_unlock(psd); return; remove: list_del(&ce->node); if (ce->enabled_when_prepared) psd->clock_op_might_sleep--; pm_clk_list_unlock(psd); __pm_clk_remove(ce); } EXPORT_SYMBOL_GPL(pm_clk_remove_clk); /** * pm_clk_init - Initialize a device's list of power management clocks. * @dev: Device to initialize the list of PM clocks for. * * Initialize the lock and clock_list members of the device's pm_subsys_data * object, set the count of clocks that might sleep to 0. */ void pm_clk_init(struct device *dev) { struct pm_subsys_data *psd = dev_to_psd(dev); if (psd) { INIT_LIST_HEAD(&psd->clock_list); mutex_init(&psd->clock_mutex); psd->clock_op_might_sleep = 0; } } EXPORT_SYMBOL_GPL(pm_clk_init); /** * pm_clk_create - Create and initialize a device's list of PM clocks. * @dev: Device to create and initialize the list of PM clocks for. * * Allocate a struct pm_subsys_data object, initialize its lock and clock_list * members and make the @dev's power.subsys_data field point to it. */ int pm_clk_create(struct device *dev) { return dev_pm_get_subsys_data(dev); } EXPORT_SYMBOL_GPL(pm_clk_create); /** * pm_clk_destroy - Destroy a device's list of power management clocks. * @dev: Device to destroy the list of PM clocks for. * * Clear the @dev's power.subsys_data field, remove the list of clock entries * from the struct pm_subsys_data object pointed to by it before and free * that object. */ void pm_clk_destroy(struct device *dev) { struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce, *c; struct list_head list; if (!psd) return; INIT_LIST_HEAD(&list); pm_clk_list_lock(psd); list_for_each_entry_safe_reverse(ce, c, &psd->clock_list, node) list_move(&ce->node, &list); psd->clock_op_might_sleep = 0; pm_clk_list_unlock(psd); dev_pm_put_subsys_data(dev); list_for_each_entry_safe_reverse(ce, c, &list, node) { list_del(&ce->node); __pm_clk_remove(ce); } } EXPORT_SYMBOL_GPL(pm_clk_destroy); static void pm_clk_destroy_action(void *data) { pm_clk_destroy(data); } int devm_pm_clk_create(struct device *dev) { int ret; ret = pm_clk_create(dev); if (ret) return ret; return devm_add_action_or_reset(dev, pm_clk_destroy_action, dev); } EXPORT_SYMBOL_GPL(devm_pm_clk_create); /** * pm_clk_suspend - Disable clocks in a device's PM clock list. * @dev: Device to disable the clocks for. */ int pm_clk_suspend(struct device *dev) { struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; unsigned long flags; int ret; dev_dbg(dev, "%s()\n", __func__); if (!psd) return 0; ret = pm_clk_op_lock(psd, &flags, __func__); if (ret) return ret; list_for_each_entry_reverse(ce, &psd->clock_list, node) { if (ce->status == PCE_STATUS_ENABLED) { if (ce->enabled_when_prepared) { clk_disable_unprepare(ce->clk); ce->status = PCE_STATUS_ACQUIRED; } else { clk_disable(ce->clk); ce->status = PCE_STATUS_PREPARED; } } } pm_clk_op_unlock(psd, &flags); return 0; } EXPORT_SYMBOL_GPL(pm_clk_suspend); /** * pm_clk_resume - Enable clocks in a device's PM clock list. * @dev: Device to enable the clocks for. */ int pm_clk_resume(struct device *dev) { struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; unsigned long flags; int ret; dev_dbg(dev, "%s()\n", __func__); if (!psd) return 0; ret = pm_clk_op_lock(psd, &flags, __func__); if (ret) return ret; list_for_each_entry(ce, &psd->clock_list, node) __pm_clk_enable(dev, ce); pm_clk_op_unlock(psd, &flags); return 0; } EXPORT_SYMBOL_GPL(pm_clk_resume); /** * pm_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 pm_domain member of that object is copied to the device's * pm_domain field and its con_ids member is used to populate the device's list * of PM clocks, depending on @action. * * If the device's pm_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_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->pm_domain) break; error = pm_clk_create(dev); if (error) break; dev_pm_domain_set(dev, clknb->pm_domain); if (clknb->con_ids[0]) { for (con_id = clknb->con_ids; *con_id; con_id++) pm_clk_add(dev, *con_id); } else { pm_clk_add(dev, NULL); } break; case BUS_NOTIFY_DEL_DEVICE: if (dev->pm_domain != clknb->pm_domain) break; dev_pm_domain_set(dev, NULL); pm_clk_destroy(dev); break; } return 0; } int pm_clk_runtime_suspend(struct device *dev) { int ret; dev_dbg(dev, "%s\n", __func__); ret = pm_generic_runtime_suspend(dev); if (ret) { dev_err(dev, "failed to suspend device\n"); return ret; } ret = pm_clk_suspend(dev); if (ret) { dev_err(dev, "failed to suspend clock\n"); pm_generic_runtime_resume(dev); return ret; } return 0; } EXPORT_SYMBOL_GPL(pm_clk_runtime_suspend); int pm_clk_runtime_resume(struct device *dev) { int ret; dev_dbg(dev, "%s\n", __func__); ret = pm_clk_resume(dev); if (ret) { dev_err(dev, "failed to resume clock\n"); return ret; } return pm_generic_runtime_resume(dev); } EXPORT_SYMBOL_GPL(pm_clk_runtime_resume); #else /* !CONFIG_PM_CLK */ /** * 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_prepare_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_unprepare(clk); clk_put(clk); dev_info(dev, "Runtime PM disabled, clock forced off.\n"); } } /** * pm_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_clk_notify(struct notifier_block *nb, unsigned long action, void *data) { struct pm_clk_notifier_block *clknb; struct device *dev = data; char **con_id; dev_dbg(dev, "%s() %ld\n", __func__, action); clknb = container_of(nb, struct pm_clk_notifier_block, nb); switch (action) { case BUS_NOTIFY_BIND_DRIVER: if (clknb->con_ids[0]) { for (con_id = clknb->con_ids; *con_id; con_id++) enable_clock(dev, *con_id); } else { enable_clock(dev, NULL); } break; case BUS_NOTIFY_DRIVER_NOT_BOUND: case BUS_NOTIFY_UNBOUND_DRIVER: if (clknb->con_ids[0]) { for (con_id = clknb->con_ids; *con_id; con_id++) disable_clock(dev, *con_id); } else { disable_clock(dev, NULL); } break; } return 0; } #endif /* !CONFIG_PM_CLK */ /** * pm_clk_add_notifier - Add bus type notifier for power management 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_clk_notify(). However, * the remaining members of @clknb should be populated prior to calling this * routine. */ void pm_clk_add_notifier(struct bus_type *bus, struct pm_clk_notifier_block *clknb) { if (!bus || !clknb) return; clknb->nb.notifier_call = pm_clk_notify; bus_register_notifier(bus, &clknb->nb); } EXPORT_SYMBOL_GPL(pm_clk_add_notifier);
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