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788 lines
19 KiB
788 lines
19 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
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* drivers/base/power/clock_ops.c - Generic clock manipulation PM callbacks |
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* |
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* Copyright (c) 2011 Rafael J. Wysocki <[email protected]>, Renesas Electronics Corp. |
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*/ |
|
|
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#include <linux/kernel.h> |
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#include <linux/device.h> |
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#include <linux/io.h> |
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#include <linux/pm.h> |
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#include <linux/pm_clock.h> |
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#include <linux/clk.h> |
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#include <linux/clkdev.h> |
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#include <linux/of_clk.h> |
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#include <linux/slab.h> |
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#include <linux/err.h> |
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#include <linux/pm_domain.h> |
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#include <linux/pm_runtime.h> |
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|
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#ifdef CONFIG_PM_CLK |
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|
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enum pce_status { |
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PCE_STATUS_NONE = 0, |
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PCE_STATUS_ACQUIRED, |
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PCE_STATUS_PREPARED, |
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PCE_STATUS_ENABLED, |
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PCE_STATUS_ERROR, |
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}; |
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|
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struct pm_clock_entry { |
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struct list_head node; |
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char *con_id; |
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struct clk *clk; |
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enum pce_status status; |
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bool enabled_when_prepared; |
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}; |
|
|
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/** |
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* pm_clk_list_lock - ensure exclusive access for modifying the PM clock |
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* entry list. |
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* @psd: pm_subsys_data instance corresponding to the PM clock entry list |
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* and clk_op_might_sleep count to be modified. |
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* |
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* Get exclusive access before modifying the PM clock entry list and the |
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* clock_op_might_sleep count to guard against concurrent modifications. |
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* This also protects against a concurrent clock_op_might_sleep and PM clock |
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* entry list usage in pm_clk_suspend()/pm_clk_resume() that may or may not |
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* happen in atomic context, hence both the mutex and the spinlock must be |
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* taken here. |
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*/ |
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static void pm_clk_list_lock(struct pm_subsys_data *psd) |
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__acquires(&psd->lock) |
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{ |
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mutex_lock(&psd->clock_mutex); |
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spin_lock_irq(&psd->lock); |
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} |
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|
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/** |
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* pm_clk_list_unlock - counterpart to pm_clk_list_lock(). |
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* @psd: the same pm_subsys_data instance previously passed to |
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* pm_clk_list_lock(). |
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*/ |
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static void pm_clk_list_unlock(struct pm_subsys_data *psd) |
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__releases(&psd->lock) |
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{ |
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spin_unlock_irq(&psd->lock); |
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mutex_unlock(&psd->clock_mutex); |
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} |
|
|
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/** |
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* pm_clk_op_lock - ensure exclusive access for performing clock operations. |
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* @psd: pm_subsys_data instance corresponding to the PM clock entry list |
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* and clk_op_might_sleep count being used. |
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* @flags: stored irq flags. |
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* @fn: string for the caller function's name. |
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* |
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* This is used by pm_clk_suspend() and pm_clk_resume() to guard |
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* against concurrent modifications to the clock entry list and the |
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* clock_op_might_sleep count. If clock_op_might_sleep is != 0 then |
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* only the mutex can be locked and those functions can only be used in |
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* non atomic context. If clock_op_might_sleep == 0 then these functions |
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* may be used in any context and only the spinlock can be locked. |
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* Returns -EINVAL if called in atomic context when clock ops might sleep. |
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*/ |
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static int pm_clk_op_lock(struct pm_subsys_data *psd, unsigned long *flags, |
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const char *fn) |
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/* sparse annotations don't work here as exit state isn't static */ |
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{ |
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bool atomic_context = in_atomic() || irqs_disabled(); |
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|
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try_again: |
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spin_lock_irqsave(&psd->lock, *flags); |
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if (!psd->clock_op_might_sleep) { |
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/* the __release is there to work around sparse limitations */ |
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__release(&psd->lock); |
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return 0; |
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} |
|
|
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/* bail out if in atomic context */ |
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if (atomic_context) { |
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pr_err("%s: atomic context with clock_ops_might_sleep = %d", |
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fn, psd->clock_op_might_sleep); |
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spin_unlock_irqrestore(&psd->lock, *flags); |
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might_sleep(); |
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return -EPERM; |
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} |
|
|
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/* we must switch to the mutex */ |
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spin_unlock_irqrestore(&psd->lock, *flags); |
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mutex_lock(&psd->clock_mutex); |
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|
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/* |
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* There was a possibility for psd->clock_op_might_sleep |
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* to become 0 above. Keep the mutex only if not the case. |
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*/ |
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if (likely(psd->clock_op_might_sleep)) |
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return 0; |
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|
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mutex_unlock(&psd->clock_mutex); |
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goto try_again; |
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} |
|
|
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/** |
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* pm_clk_op_unlock - counterpart to pm_clk_op_lock(). |
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* @psd: the same pm_subsys_data instance previously passed to |
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* pm_clk_op_lock(). |
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* @flags: irq flags provided by pm_clk_op_lock(). |
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*/ |
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static void pm_clk_op_unlock(struct pm_subsys_data *psd, unsigned long *flags) |
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/* sparse annotations don't work here as entry state isn't static */ |
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{ |
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if (psd->clock_op_might_sleep) { |
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mutex_unlock(&psd->clock_mutex); |
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} else { |
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/* the __acquire is there to work around sparse limitations */ |
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__acquire(&psd->lock); |
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spin_unlock_irqrestore(&psd->lock, *flags); |
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} |
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} |
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|
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/** |
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* pm_clk_enable - Enable a clock, reporting any errors |
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* @dev: The device for the given clock |
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* @ce: PM clock entry corresponding to the clock. |
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*/ |
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static inline void __pm_clk_enable(struct device *dev, struct pm_clock_entry *ce) |
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{ |
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int ret; |
|
|
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switch (ce->status) { |
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case PCE_STATUS_ACQUIRED: |
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ret = clk_prepare_enable(ce->clk); |
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break; |
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case PCE_STATUS_PREPARED: |
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ret = clk_enable(ce->clk); |
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break; |
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default: |
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return; |
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} |
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if (!ret) |
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ce->status = PCE_STATUS_ENABLED; |
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else |
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dev_err(dev, "%s: failed to enable clk %p, error %d\n", |
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__func__, ce->clk, ret); |
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} |
|
|
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/** |
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* pm_clk_acquire - Acquire a device clock. |
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* @dev: Device whose clock is to be acquired. |
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* @ce: PM clock entry corresponding to the clock. |
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*/ |
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static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) |
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{ |
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if (!ce->clk) |
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ce->clk = clk_get(dev, ce->con_id); |
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if (IS_ERR(ce->clk)) { |
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ce->status = PCE_STATUS_ERROR; |
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return; |
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} else if (clk_is_enabled_when_prepared(ce->clk)) { |
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/* we defer preparing the clock in that case */ |
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ce->status = PCE_STATUS_ACQUIRED; |
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ce->enabled_when_prepared = true; |
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} else if (clk_prepare(ce->clk)) { |
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ce->status = PCE_STATUS_ERROR; |
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dev_err(dev, "clk_prepare() failed\n"); |
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return; |
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} else { |
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ce->status = PCE_STATUS_PREPARED; |
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} |
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dev_dbg(dev, "Clock %pC con_id %s managed by runtime PM.\n", |
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ce->clk, ce->con_id); |
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} |
|
|
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static int __pm_clk_add(struct device *dev, const char *con_id, |
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struct clk *clk) |
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{ |
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struct pm_subsys_data *psd = dev_to_psd(dev); |
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struct pm_clock_entry *ce; |
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|
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if (!psd) |
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return -EINVAL; |
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|
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ce = kzalloc(sizeof(*ce), GFP_KERNEL); |
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if (!ce) |
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return -ENOMEM; |
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|
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if (con_id) { |
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ce->con_id = kstrdup(con_id, GFP_KERNEL); |
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if (!ce->con_id) { |
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kfree(ce); |
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return -ENOMEM; |
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} |
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} else { |
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if (IS_ERR(clk)) { |
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kfree(ce); |
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return -ENOENT; |
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} |
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ce->clk = clk; |
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} |
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pm_clk_acquire(dev, ce); |
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pm_clk_list_lock(psd); |
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list_add_tail(&ce->node, &psd->clock_list); |
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if (ce->enabled_when_prepared) |
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psd->clock_op_might_sleep++; |
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pm_clk_list_unlock(psd); |
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return 0; |
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} |
|
|
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/** |
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* pm_clk_add - Start using a device clock for power management. |
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* @dev: Device whose clock is going to be used for power management. |
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* @con_id: Connection ID of the clock. |
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* |
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* Add the clock represented by @con_id to the list of clocks used for |
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* the power management of @dev. |
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*/ |
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int pm_clk_add(struct device *dev, const char *con_id) |
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{ |
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return __pm_clk_add(dev, con_id, NULL); |
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} |
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EXPORT_SYMBOL_GPL(pm_clk_add); |
|
|
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/** |
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* pm_clk_add_clk - Start using a device clock for power management. |
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* @dev: Device whose clock is going to be used for power management. |
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* @clk: Clock pointer |
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* |
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* Add the clock to the list of clocks used for the power management of @dev. |
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* The power-management code will take control of the clock reference, so |
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* callers should not call clk_put() on @clk after this function sucessfully |
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* returned. |
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*/ |
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int pm_clk_add_clk(struct device *dev, struct clk *clk) |
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{ |
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return __pm_clk_add(dev, NULL, clk); |
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} |
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EXPORT_SYMBOL_GPL(pm_clk_add_clk); |
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|
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|
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/** |
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* of_pm_clk_add_clk - Start using a device clock for power management. |
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* @dev: Device whose clock is going to be used for power management. |
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* @name: Name of clock that is going to be used for power management. |
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* |
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* Add the clock described in the 'clocks' device-tree node that matches |
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* with the 'name' provided, to the list of clocks used for the power |
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* management of @dev. On success, returns 0. Returns a negative error |
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* code if the clock is not found or cannot be added. |
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*/ |
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int of_pm_clk_add_clk(struct device *dev, const char *name) |
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{ |
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struct clk *clk; |
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int ret; |
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|
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if (!dev || !dev->of_node || !name) |
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return -EINVAL; |
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|
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clk = of_clk_get_by_name(dev->of_node, name); |
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if (IS_ERR(clk)) |
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return PTR_ERR(clk); |
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|
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ret = pm_clk_add_clk(dev, clk); |
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if (ret) { |
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clk_put(clk); |
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return ret; |
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} |
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return 0; |
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} |
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EXPORT_SYMBOL_GPL(of_pm_clk_add_clk); |
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|
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/** |
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* of_pm_clk_add_clks - Start using device clock(s) for power management. |
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* @dev: Device whose clock(s) is going to be used for power management. |
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* |
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* Add a series of clocks described in the 'clocks' device-tree node for |
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* a device to the list of clocks used for the power management of @dev. |
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* On success, returns the number of clocks added. Returns a negative |
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* error code if there are no clocks in the device node for the device |
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* or if adding a clock fails. |
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*/ |
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int of_pm_clk_add_clks(struct device *dev) |
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{ |
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struct clk **clks; |
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int i, count; |
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int ret; |
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|
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if (!dev || !dev->of_node) |
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return -EINVAL; |
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count = of_clk_get_parent_count(dev->of_node); |
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if (count <= 0) |
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return -ENODEV; |
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clks = kcalloc(count, sizeof(*clks), GFP_KERNEL); |
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if (!clks) |
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return -ENOMEM; |
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for (i = 0; i < count; i++) { |
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clks[i] = of_clk_get(dev->of_node, i); |
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if (IS_ERR(clks[i])) { |
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ret = PTR_ERR(clks[i]); |
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goto error; |
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} |
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ret = pm_clk_add_clk(dev, clks[i]); |
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if (ret) { |
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clk_put(clks[i]); |
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goto error; |
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} |
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} |
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kfree(clks); |
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return i; |
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error: |
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while (i--) |
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pm_clk_remove_clk(dev, clks[i]); |
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|
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kfree(clks); |
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|
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return ret; |
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} |
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EXPORT_SYMBOL_GPL(of_pm_clk_add_clks); |
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|
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/** |
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* __pm_clk_remove - Destroy PM clock entry. |
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* @ce: PM clock entry to destroy. |
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*/ |
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static void __pm_clk_remove(struct pm_clock_entry *ce) |
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{ |
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if (!ce) |
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return; |
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|
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switch (ce->status) { |
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case PCE_STATUS_ENABLED: |
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clk_disable(ce->clk); |
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fallthrough; |
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case PCE_STATUS_PREPARED: |
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clk_unprepare(ce->clk); |
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fallthrough; |
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case PCE_STATUS_ACQUIRED: |
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case PCE_STATUS_ERROR: |
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if (!IS_ERR(ce->clk)) |
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clk_put(ce->clk); |
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break; |
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default: |
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break; |
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} |
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|
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kfree(ce->con_id); |
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kfree(ce); |
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} |
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|
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/** |
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* pm_clk_remove - Stop using a device clock for power management. |
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* @dev: Device whose clock should not be used for PM any more. |
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* @con_id: Connection ID of the clock. |
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* |
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* Remove the clock represented by @con_id from the list of clocks used for |
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* the power management of @dev. |
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*/ |
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void pm_clk_remove(struct device *dev, const char *con_id) |
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{ |
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struct pm_subsys_data *psd = dev_to_psd(dev); |
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struct pm_clock_entry *ce; |
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|
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if (!psd) |
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return; |
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|
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pm_clk_list_lock(psd); |
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|
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list_for_each_entry(ce, &psd->clock_list, node) { |
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if (!con_id && !ce->con_id) |
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goto remove; |
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else if (!con_id || !ce->con_id) |
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continue; |
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else if (!strcmp(con_id, ce->con_id)) |
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goto remove; |
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} |
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pm_clk_list_unlock(psd); |
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return; |
|
|
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remove: |
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list_del(&ce->node); |
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if (ce->enabled_when_prepared) |
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psd->clock_op_might_sleep--; |
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pm_clk_list_unlock(psd); |
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|
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__pm_clk_remove(ce); |
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} |
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EXPORT_SYMBOL_GPL(pm_clk_remove); |
|
|
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/** |
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* pm_clk_remove_clk - Stop using a device clock for power management. |
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* @dev: Device whose clock should not be used for PM any more. |
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* @clk: Clock pointer |
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* |
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* Remove the clock pointed to by @clk from the list of clocks used for |
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* the power management of @dev. |
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*/ |
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void pm_clk_remove_clk(struct device *dev, struct clk *clk) |
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{ |
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struct pm_subsys_data *psd = dev_to_psd(dev); |
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struct pm_clock_entry *ce; |
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|
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if (!psd || !clk) |
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return; |
|
|
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pm_clk_list_lock(psd); |
|
|
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list_for_each_entry(ce, &psd->clock_list, node) { |
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if (clk == ce->clk) |
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goto remove; |
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} |
|
|
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pm_clk_list_unlock(psd); |
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return; |
|
|
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remove: |
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list_del(&ce->node); |
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if (ce->enabled_when_prepared) |
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psd->clock_op_might_sleep--; |
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pm_clk_list_unlock(psd); |
|
|
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__pm_clk_remove(ce); |
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} |
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EXPORT_SYMBOL_GPL(pm_clk_remove_clk); |
|
|
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/** |
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* pm_clk_init - Initialize a device's list of power management clocks. |
|
* @dev: Device to initialize the list of PM clocks for. |
|
* |
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* Initialize the lock and clock_list members of the device's pm_subsys_data |
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* object, set the count of clocks that might sleep to 0. |
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*/ |
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void pm_clk_init(struct device *dev) |
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{ |
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struct pm_subsys_data *psd = dev_to_psd(dev); |
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if (psd) { |
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INIT_LIST_HEAD(&psd->clock_list); |
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mutex_init(&psd->clock_mutex); |
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psd->clock_op_might_sleep = 0; |
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} |
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} |
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EXPORT_SYMBOL_GPL(pm_clk_init); |
|
|
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/** |
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* 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. |
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* |
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* 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. |
|
*/ |
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int pm_clk_create(struct device *dev) |
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{ |
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return dev_pm_get_subsys_data(dev); |
|
} |
|
EXPORT_SYMBOL_GPL(pm_clk_create); |
|
|
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/** |
|
* 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) |
|
{ |
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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); |
|
|
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list_for_each_entry_safe_reverse(ce, c, &list, node) { |
|
list_del(&ce->node); |
|
__pm_clk_remove(ce); |
|
} |
|
} |
|
EXPORT_SYMBOL_GPL(pm_clk_destroy); |
|
|
|
/** |
|
* 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);
|
|
|