d4f8138354
A device may have specific HW constraints that must be obeyed to, before its corresponding PM domain (genpd) can be powered off - and vice verse at power on. These constraints can't be managed through the regular runtime PM based deployment for a device, because the access pattern for it, isn't always request based. In other words, using the runtime PM callbacks to deal with the constraints doesn't work for these cases. For these reasons, let's instead add a PM domain power on/off notification mechanism to genpd. To add/remove a notifier for a device, the device must already have been attached to the genpd, which also means that it needs to be a part of the PM domain topology. To add/remove a notifier, let's introduce two genpd specific functions: - dev_pm_genpd_add|remove_notifier() Note that, to further clarify when genpd power on/off notifiers may be used, one can compare with the existing CPU_CLUSTER_PM_ENTER|EXIT notifiers. In the long run, the genpd power on/off notifiers should be able to replace them, but that requires additional genpd based platform support for the current users. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Lina Iyer <ilina@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.