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path: root/drivers/base/power/common.c
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2019-11-13PM / Domains: Introduce dev_pm_domain_start()Ulf Hansson
For a subsystem/driver that either doesn't support runtime PM or makes use of pm_runtime_set_active() during ->probe(), may try to access its device when probing, even if it may not be fully powered on from the PM domain's point of view. This may be the case when the used PM domain is a genpd provider, that implements genpd's ->start|stop() device callbacks. There are cases where the subsystem/driver managed to avoid the above problem, simply by calling pm_runtime_enable() and pm_runtime_get_sync() during ->probe(). However, this approach comes with a drawback, especially if the subsystem/driver implements a ->runtime_resume() callback. More precisely, the subsystem/driver then needs to use a device flag, which is checked in its ->runtime_resume() callback, as to avoid powering on its resources the first time the callback is invoked. This is needed because the subsystem/driver has already powered on the resources for the device, during ->probe() and before it called pm_runtime_get_sync(). In a way to avoid this boilerplate code and the inefficient check for "if (first_time_suspend)" in the ->runtime_resume() callback for these subsystems/drivers, let's introduce and export a dev_pm_domain_start() function, that may be called during ->probe() instead. Moreover, let the dev_pm_domain_start() invoke an optional ->start() callback, added to the struct dev_pm_domain, as to allow a PM domain specific implementation. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-04drivers: base: power: add proper SPDX identifiers on files that did not have ↵Greg Kroah-Hartman
them. There were a few files in the driver core power code that did not have SPDX identifiers on them, so fix that up. At the same time, remove the "free form" text that specified the license of the file, as that is impossible for any tool to properly parse. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-15PM / Domains: Mark "name" const in dev_pm_domain_attach_by_name()Douglas Anderson
As of the patch ("PM / Domains: Mark "name" const in genpd_dev_pm_attach_by_name()") it's clear that the name in dev_pm_domain_attach_by_name() can be const. Mark it as so. This allows drivers to pass in a name that was declared "const" in a driver. Fixes: 27dceb81f445 ("PM / Domains: Introduce dev_pm_domain_attach_by_name()") Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-07-09PM / Domains: Introduce dev_pm_domain_attach_by_name()Ulf Hansson
For the multiple PM domain case, let's introduce a new API called dev_pm_domain_attach_by_name(). This allows a consumer driver to associate its device with one of its PM domains, by using a name based lookup. Do note that, currently it's only genpd that supports multiple PM domains per device, but dev_pm_domain_attach_by_name() can easily by extended to cover other PM domain types, if/when needed. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Rajendra Nayak <rnayak@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-06-06PM / Domains: Add dev_pm_domain_attach_by_id() to manage multi PM domainsUlf Hansson
The existing dev_pm_domain_attach() function, allows a single PM domain to be attached per device. To be able to support devices that are partitioned across multiple PM domains, let's introduce a new interface, dev_pm_domain_attach_by_id(). The dev_pm_domain_attach_by_id() returns a new allocated struct device with the corresponding attached PM domain. This enables for example a driver to operate on the new device from a power management point of view. The driver may then also benefit from using the received device, to set up so called device-links towards its original device. Depending on the situation, these links may then be dynamically changed. The new interface is typically called by drivers during their probe phase, in case they manages devices which uses multiple PM domains. If that is the case, the driver also becomes responsible of managing the detaching of the PM domains, which typically should be done at the remove phase. Detaching is done by calling the existing dev_pm_domain_detach() function and for each of the received devices from dev_pm_domain_attach_by_id(). Note, currently its only genpd that supports multiple PM domains per device, but dev_pm_domain_attach_by_id() can easily by extended to cover other PM domain types, if/when needed. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-17PM / domains: Improve wording of dev_pm_domain_attach() commentGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-15PM / Domains: Don't return -EEXIST at attach when PM domain existsUlf Hansson
As dev_pm_domain_attach() isn't the only way to assign PM domain pointers to devices, clearly we must allow a device to have the pointer already being assigned. For this reason, return 0 instead of -EEXIST. Reported-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Tested-by: Krzysztof Kozlowski <krzk@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-14PM / Domains: Allow a better error handling of dev_pm_domain_attach()Ulf Hansson
The callers of dev_pm_domain_attach() currently checks the returned error code for -EPROBE_DEFER and needs to ignore other error codes. This is an unnecessary limitation, which also leads to a rather strange behaviour in the error path. Address this limitation, by changing the return codes from acpi_dev_pm_attach() and genpd_dev_pm_attach(). More precisely, let them return 0, when no PM domain is needed for the device and then return 1, in case the device was successfully attached to its PM domain. In this way, dev_pm_domain_attach(), gets a better understanding of what happens in the attach attempts and also allowing its caller to better act on real errors codes. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-14PM / Domains: Check for existing PM domain in dev_pm_domain_attach()Ulf Hansson
Instead of checking if an existing PM domain pointer has been assigned in genpd_dev_pm_attach() and acpi_dev_pm_attach(), move the check to the common path in dev_pm_domain_attach(), thus potentially avoid one unnecessary check. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-02-03PM: Avoid false-positive warnings in dev_pm_domain_set()Rafael J. Wysocki
There is a WARN_ON() in dev_pm_domain_set() that triggers on attempts to set the pm_domain pointer for devices with a driver bound. However, that WARN_ON() triggers on attempts to clear the pointer too and the test it uses is based on checking the device's p->knode_driver pointer which still is set when the device bus type's/driver's ->remove callback has been executed. This leads to false-positive warnings when bus type code calls dev_pm_domain_set() to clear the pm_domain pointer after invoking the driver's ->remove() callback. To avoid those false-positives, make dev_pm_domain_set() check if the pointer passed to it is NULL and skip the warning in that case. Fixes: 989561de9b51 (PM / Domains: add setter for dev.pm_domain) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Sinan Kaya <okaya@codeaurora.org> Tested-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
2016-01-08PM / sleep: Go direct_complete if driver has no callbacksTomeu Vizoso
If a suitable prepare callback cannot be found for a given device and its driver has no PM callbacks at all, assume that it can go direct to complete when the system goes to sleep. The reason for this is that there's lots of devices in a system that do no PM at all and there's no reason for them to prevent their ancestors to do direct_complete if they can support it. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-08PM / Domains: add setter for dev.pm_domainTomeu Vizoso
Adds a function that sets the pointer to dev_pm_domain in struct device and that warns if the device has already finished probing. The reason why we want to enforce that is because in the general case that can cause problems and also that we can simplify code quite a bit if we can always assume that. This patch also changes all current code that directly sets the dev.pm_domain pointer. Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-02PM / core: fix typo in documentationManuel Pégourié-Gonnard
The documentation for detach() said attach. Signed-off-by: Manuel Pégourié-Gonnard <mpg@elzevir.fr> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03PM: Convert dev_pm_put_subsys_data() into a void functionUlf Hansson
Clients using the dev_pm_put_subsys_data() API isn't interested of a return value. They care only of decreasing a reference to the device's pm_subsys_data. So, let's convert the API to a void function, which anyway seems like reasonable thing to do. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03PM: Update function header for dev_pm_get_subsys_data()Ulf Hansson
The commit "PM: Make dev_pm_get_subsys_data() always return 0 on success" changed the return value from dev_pm_get_subsys_data(). Let's update the comment in the function header to reflect this change as well. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-09-22PM / Domains: Add APIs to attach/detach a PM domain for a deviceUlf Hansson
To maintain scalability let's add common methods to attach and detach a PM domain for a device, dev_pm_domain_attach|detach(). Typically dev_pm_domain_attach() shall be invoked from subsystem level code at the probe phase to try to attach a device to its PM domain. The reversed actions may be done a the remove phase and then by invoking dev_pm_domain_detach(). When attachment succeeds, the attach function should assign its corresponding detach function to a new ->detach() callback added in the struct dev_pm_domain. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Philipp Zabel <p.zabel@pengutronix.de> Reviewed-by: Kevin Hilman <khilman@linaro.org> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-14drivers/base: delete non-required instances of include <linux/init.h>Paul Gortmaker
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. Cc: Len Brown <len.brown@intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mark Brown <broonie@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-12PM: Avoid calling kfree() under spinlock in dev_pm_put_subsys_data()Shuah Khan
Fix dev_pm_put_subsys_data() so that it doesn't call kfree() under a spinlock and make it return 1 whenever it leaves NULL power.subsys_data (regardless of the reason). Signed-off-by: Shuah Khan <shuah.kh@samsung.com> Reviewed-by: Pavel Machek <pavel@ucw.cz> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-08-08PM: Make dev_pm_get_subsys_data() always return 0 on successRafael J. Wysocki
Commits 1d5fcfec22 (PM / Domains: Add device domain data reference counter) and 62d4490294 (PM / Domains: Allow device callbacks to be added at any time) added checks for the return value of dev_pm_get_subsys_data(), but those checks were incorrect, because that function returned 1 on success in some cases. Since all of the existing users of dev_pm_get_subsys_data() don't use the positive value returned by it on success, change its definition so that it always returns 0 when successful. Reported-by: Heiko Stübner <heiko@sntech.de> Reported-by: Tushar Behera <tushar.behera@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-03-11device.h: cleanup users outside of linux/include (C files)Paul Gortmaker
For files that are actively using linux/device.h, make sure that they call it out. This will allow us to clean up some of the implicit uses of linux/device.h within include/* without introducing build regressions. Yes, this was created by "cheating" -- i.e. the headers were cleaned up, and then the fallout was found and fixed, and then the two commits were reordered. This ensures we don't introduce build regressions into the git history. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31drivers/base: change module.h -> export.h in power/common.cPaul Gortmaker
This file isn't using full modular functionality, and hence can be "downgraded" to just using export.h Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-08-25PM: Move clock-related definitions and headers to separate fileRafael J. Wysocki
Since the PM clock management code in drivers/base/power/clock_ops.c is used for both runtime PM and system suspend/hibernation, the definitions of data structures and headers related to it should not be located in include/linux/pm_rumtime.h. Move them to a separate header file. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM: Reference counting of power.subsys_dataRafael J. Wysocki
Since the power.subsys_data device field will be used by multiple filesystems, introduce a reference counting mechanism for it to avoid freeing it prematurely or changing its value at a wrong time. Make the PM clocks management code that currently is the only user of power.subsys_data use the new reference counting. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>