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![Dmitry Baryshkov](/assets/img/avatar_default.png)
A typical code pattern for pm_clk_create() call is to call it in the _probe function and to call pm_clk_destroy() both from _probe error path and from _remove function. For some drivers the whole remove function would consist of the call to pm_remove_disable(). Add helper function to replace this bolierplate piece of code. Calling devm_pm_clk_create() removes the need for calling pm_clk_destroy() both in the probe()'s error path and in the remove() function. Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Link: https://lore.kernel.org/r/20210731195034.979084-3-dmitry.baryshkov@linaro.org Acked-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
805 lines
19 KiB
C
805 lines
19 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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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 <rjw@sisk.pl>, 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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#ifdef CONFIG_PM_CLK
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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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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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* 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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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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* 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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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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* __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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if (!psd)
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return -EINVAL;
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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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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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* 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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if (!dev || !dev->of_node || !name)
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return -EINVAL;
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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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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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* 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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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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kfree(clks);
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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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* __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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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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kfree(ce->con_id);
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kfree(ce);
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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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if (!psd)
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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 (!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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__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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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.
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* @dev: Device to initialize the list of PM clocks for.
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*
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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.
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* @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
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* members and make the @dev's power.subsys_data field point to it.
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*/
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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);
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}
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EXPORT_SYMBOL_GPL(pm_clk_create);
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/**
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* pm_clk_destroy - Destroy a device's list of power management clocks.
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* @dev: Device to destroy the list of PM clocks for.
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*
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* Clear the @dev's power.subsys_data field, remove the list of clock entries
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* from the struct pm_subsys_data object pointed to by it before and free
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* that object.
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*/
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void pm_clk_destroy(struct device *dev)
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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, *c;
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struct list_head list;
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if (!psd)
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return;
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INIT_LIST_HEAD(&list);
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pm_clk_list_lock(psd);
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|
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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);
|