WSL2-Linux-Kernel/drivers/base/power/clock_ops.c

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19 KiB
C
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// 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>
PM / clk: Fix broken build due to non-matching code and header #ifdefs If an architecture's main Kconfig file doesn't include kernel/power/Kconfig, but CONFIG_PM=y and HAVE_CLK=y (e.g. m68knommu allmodconfig): drivers/base/power/clock_ops.c: In function ‘__pm_clk_add’: drivers/base/power/clock_ops.c:106: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:120: error: redefinition of ‘pm_clk_add’ include/linux/pm_clock.h:64: error: previous definition of ‘pm_clk_add’ was here drivers/base/power/clock_ops.c:135: error: redefinition of ‘pm_clk_add_clk’ include/linux/pm_clock.h:69: error: previous definition of ‘pm_clk_add_clk’ was here drivers/base/power/clock_ops.c:171: error: redefinition of ‘pm_clk_remove’ include/linux/pm_clock.h:73: error: previous definition of ‘pm_clk_remove’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_remove’: drivers/base/power/clock_ops.c:180: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c:180: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:207: error: redefinition of ‘pm_clk_init’ include/linux/pm_clock.h:54: error: previous definition of ‘pm_clk_init’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_init’: drivers/base/power/clock_ops.c:210: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:221: error: redefinition of ‘pm_clk_create’ include/linux/pm_clock.h:57: error: previous definition of ‘pm_clk_create’ was here drivers/base/power/clock_ops.c:234: error: redefinition of ‘pm_clk_destroy’ include/linux/pm_clock.h:61: error: previous definition of ‘pm_clk_destroy’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_destroy’: drivers/base/power/clock_ops.c:246: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c:246: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:263: error: expected identifier or ‘(’ before ‘void’ drivers/base/power/clock_ops.c:263: error: expected ‘)’ before numeric constant drivers/base/power/clock_ops.c:293: error: expected identifier or ‘(’ before ‘void’ drivers/base/power/clock_ops.c:293: error: expected ‘)’ before numeric constant drivers/base/power/clock_ops.c: In function ‘pm_clk_runtime_suspend’: drivers/base/power/clock_ops.c:384: error: called object ‘0u’ is not a function drivers/base/power/clock_ops.c: In function ‘pm_clk_runtime_resume’: drivers/base/power/clock_ops.c:400: error: called object ‘0u’ is not a function This happens because: - drivers/base/power/clock_ops.c depends on CONFIG_HAVE_CLK, - the failing code inside clock_ops.c additionally depends on CONFIG_PM, - the forward declarations and other definitions in <linux/pm_clock.h> depend on CONFIG_PM_CLK, - CONFIG_PM_CLK is defined as PM && HAVE_CLK in kernel/power/Kconfig, but it is not included on all architectures. Fix this by protecting the failing code inside clock_ops.c by CONFIG_PM_CLK instead of CONFIG_PM, so it matches <linux/pm_clock.h>. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-19 11:16:07 +03:00
#ifdef CONFIG_PM_CLK
enum pce_status {
PCE_STATUS_NONE = 0,
PCE_STATUS_ACQUIRED,
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
bool enabled_when_prepared;
};
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
/**
* 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;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
switch (ce->status) {
case PCE_STATUS_ACQUIRED:
ret = clk_prepare_enable(ce->clk);
break;
case PCE_STATUS_PREPARED:
ret = clk_enable(ce->clk);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
break;
default:
return;
}
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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 {
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
ce->status = PCE_STATUS_PREPARED;
}
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
pm_clk_list_lock(psd);
list_add_tail(&ce->node, &psd->clock_list);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
pm_clk_list_unlock(psd);
return;
remove:
list_del(&ce->node);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
pm_clk_list_lock(psd);
list_for_each_entry(ce, &psd->clock_list, node) {
if (clk == ce->clk)
goto remove;
}
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
pm_clk_list_unlock(psd);
return;
remove:
list_del(&ce->node);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
* 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);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
if (psd) {
INIT_LIST_HEAD(&psd->clock_list);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
pm_clk_list_lock(psd);
list_for_each_entry_safe_reverse(ce, c, &psd->clock_list, node)
list_move(&ce->node, &list);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
psd->clock_op_might_sleep = 0;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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);
/**
* 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;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
int ret;
dev_dbg(dev, "%s()\n", __func__);
if (!psd)
return 0;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
ret = pm_clk_op_lock(psd, &flags, __func__);
if (ret)
return ret;
list_for_each_entry_reverse(ce, &psd->clock_list, node) {
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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);
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
ce->status = PCE_STATUS_PREPARED;
}
}
}
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
int ret;
dev_dbg(dev, "%s()\n", __func__);
if (!psd)
return 0;
PM: clk: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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: make PM clock layer compatible with clocks that must sleep The clock API splits its interface into sleepable ant atomic contexts: - clk_prepare/clk_unprepare for stuff that might sleep - clk_enable_clk_disable for anything that may be done in atomic context The code handling runtime PM for clocks only calls clk_disable() on suspend requests, and clk_enable on resume requests. This means that runtime PM with clock providers that only have the prepare/unprepare methods implemented is basically useless. Many clock implementations can't accommodate atomic contexts. This is often the case when communication with the clock happens through another subsystem like I2C or SCMI. Let's make the clock PM code useful with such clocks by safely invoking clk_prepare/clk_unprepare upon resume/suspend requests. Of course, when such clocks are registered with the PM layer then pm_runtime_irq_safe() can't be used, and neither pm_runtime_suspend() nor pm_runtime_resume() may be invoked in atomic context. For clocks that do implement the enable and disable methods then everything just works as before. A note on sparse: According to https://lwn.net/Articles/109066/ there are things that sparse can't cope with. In particular, pm_clk_op_lock() and pm_clk_op_unlock() may or may not lock/unlock psd->lock depending on some runtime condition. To work around that we tell it the lock is always untaken for the purpose of static analisys. Thanks to Naresh Kamboju for reporting issues with the initial patch. Signed-off-by: Nicolas Pitre <npitre@baylibre.com> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 22:29:18 +03:00
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);
PM / clk: Fix broken build due to non-matching code and header #ifdefs If an architecture's main Kconfig file doesn't include kernel/power/Kconfig, but CONFIG_PM=y and HAVE_CLK=y (e.g. m68knommu allmodconfig): drivers/base/power/clock_ops.c: In function ‘__pm_clk_add’: drivers/base/power/clock_ops.c:106: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:120: error: redefinition of ‘pm_clk_add’ include/linux/pm_clock.h:64: error: previous definition of ‘pm_clk_add’ was here drivers/base/power/clock_ops.c:135: error: redefinition of ‘pm_clk_add_clk’ include/linux/pm_clock.h:69: error: previous definition of ‘pm_clk_add_clk’ was here drivers/base/power/clock_ops.c:171: error: redefinition of ‘pm_clk_remove’ include/linux/pm_clock.h:73: error: previous definition of ‘pm_clk_remove’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_remove’: drivers/base/power/clock_ops.c:180: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c:180: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:207: error: redefinition of ‘pm_clk_init’ include/linux/pm_clock.h:54: error: previous definition of ‘pm_clk_init’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_init’: drivers/base/power/clock_ops.c:210: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:221: error: redefinition of ‘pm_clk_create’ include/linux/pm_clock.h:57: error: previous definition of ‘pm_clk_create’ was here drivers/base/power/clock_ops.c:234: error: redefinition of ‘pm_clk_destroy’ include/linux/pm_clock.h:61: error: previous definition of ‘pm_clk_destroy’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_destroy’: drivers/base/power/clock_ops.c:246: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c:246: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:263: error: expected identifier or ‘(’ before ‘void’ drivers/base/power/clock_ops.c:263: error: expected ‘)’ before numeric constant drivers/base/power/clock_ops.c:293: error: expected identifier or ‘(’ before ‘void’ drivers/base/power/clock_ops.c:293: error: expected ‘)’ before numeric constant drivers/base/power/clock_ops.c: In function ‘pm_clk_runtime_suspend’: drivers/base/power/clock_ops.c:384: error: called object ‘0u’ is not a function drivers/base/power/clock_ops.c: In function ‘pm_clk_runtime_resume’: drivers/base/power/clock_ops.c:400: error: called object ‘0u’ is not a function This happens because: - drivers/base/power/clock_ops.c depends on CONFIG_HAVE_CLK, - the failing code inside clock_ops.c additionally depends on CONFIG_PM, - the forward declarations and other definitions in <linux/pm_clock.h> depend on CONFIG_PM_CLK, - CONFIG_PM_CLK is defined as PM && HAVE_CLK in kernel/power/Kconfig, but it is not included on all architectures. Fix this by protecting the failing code inside clock_ops.c by CONFIG_PM_CLK instead of CONFIG_PM, so it matches <linux/pm_clock.h>. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-19 11:16:07 +03:00
#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;
}
PM / clk: Fix broken build due to non-matching code and header #ifdefs If an architecture's main Kconfig file doesn't include kernel/power/Kconfig, but CONFIG_PM=y and HAVE_CLK=y (e.g. m68knommu allmodconfig): drivers/base/power/clock_ops.c: In function ‘__pm_clk_add’: drivers/base/power/clock_ops.c:106: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:120: error: redefinition of ‘pm_clk_add’ include/linux/pm_clock.h:64: error: previous definition of ‘pm_clk_add’ was here drivers/base/power/clock_ops.c:135: error: redefinition of ‘pm_clk_add_clk’ include/linux/pm_clock.h:69: error: previous definition of ‘pm_clk_add_clk’ was here drivers/base/power/clock_ops.c:171: error: redefinition of ‘pm_clk_remove’ include/linux/pm_clock.h:73: error: previous definition of ‘pm_clk_remove’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_remove’: drivers/base/power/clock_ops.c:180: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c:180: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:207: error: redefinition of ‘pm_clk_init’ include/linux/pm_clock.h:54: error: previous definition of ‘pm_clk_init’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_init’: drivers/base/power/clock_ops.c:210: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:221: error: redefinition of ‘pm_clk_create’ include/linux/pm_clock.h:57: error: previous definition of ‘pm_clk_create’ was here drivers/base/power/clock_ops.c:234: error: redefinition of ‘pm_clk_destroy’ include/linux/pm_clock.h:61: error: previous definition of ‘pm_clk_destroy’ was here drivers/base/power/clock_ops.c: In function ‘pm_clk_destroy’: drivers/base/power/clock_ops.c:246: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c:246: error: ‘struct pm_subsys_data’ has no member named ‘clock_list’ drivers/base/power/clock_ops.c: At top level: drivers/base/power/clock_ops.c:263: error: expected identifier or ‘(’ before ‘void’ drivers/base/power/clock_ops.c:263: error: expected ‘)’ before numeric constant drivers/base/power/clock_ops.c:293: error: expected identifier or ‘(’ before ‘void’ drivers/base/power/clock_ops.c:293: error: expected ‘)’ before numeric constant drivers/base/power/clock_ops.c: In function ‘pm_clk_runtime_suspend’: drivers/base/power/clock_ops.c:384: error: called object ‘0u’ is not a function drivers/base/power/clock_ops.c: In function ‘pm_clk_runtime_resume’: drivers/base/power/clock_ops.c:400: error: called object ‘0u’ is not a function This happens because: - drivers/base/power/clock_ops.c depends on CONFIG_HAVE_CLK, - the failing code inside clock_ops.c additionally depends on CONFIG_PM, - the forward declarations and other definitions in <linux/pm_clock.h> depend on CONFIG_PM_CLK, - CONFIG_PM_CLK is defined as PM && HAVE_CLK in kernel/power/Kconfig, but it is not included on all architectures. Fix this by protecting the failing code inside clock_ops.c by CONFIG_PM_CLK instead of CONFIG_PM, so it matches <linux/pm_clock.h>. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-19 11:16:07 +03:00
#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);