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    SubjectRe: [PATCH v4 0/3] Runtime Interpreted Power Sequences
    On 08/17/2012 06:47 AM, Rafael J. Wysocki wrote:
    > On Thursday, August 16, 2012, Alexandre Courbot wrote:
    >> Overdue revision of this new feature, some changes required additional thought
    >> and rework.
    >>
    >> The most important change is in the way power sequences are expressed in the
    >> device tree. In order to avoid having to specify #address-cells, #size-cells and
    >> reg properties, the @ notation in the step names is dropped, and instead a
    >> fixed, sequential naming is adopted. The type of the resource used by a step is
    >> decided by the presence of some recognized properties:
    >>
    >> power-on-sequence {
    >> step0 {
    >> regulator = "power";
    >> enable;
    >> };
    >> step1 {
    >> delay = <10000>;
    >> };
    >> step2 {
    >> pwm = "backlight";
    >> enable;
    >> };
    >> ...
    >>
    >> To me this looks safe, clear and close to the platform data representation, but
    >> needs approval from DT experts.
    >>
    >> Resources are still referenced by name instead of having their phandles defined
    >> directly inside the sequences, as previous discussion came to the conclusion
    >> that doing so would require controversial changes to the regulator and PWM
    >> frameworks, and that having the resources declared at the device level was
    >> making sense logically speaking.
    >>
    >> Other changes/fixes since last revision:
    >> * Move to drivers/power/ (hope this is ok with the maintainers?)
    >> * Use microseconds for delay
    >> * Use devm for PWM resources and remove cleanup function as all resources are
    >> devm-managed
    >> * Remove "-gpio" suffix for GPIO reference in the driver
    >> * Remove params structure
    >> * Make power_seq structure private
    >> * Number of steps in a sequence is explicitly stated instead of resorting to a
    >> "stop" sequence step
    >> * Delays are a step instead of being a step parameter
    >> * Use flexible member arrays to limit number of memory allocations
    >> * Add documentation to DT bindings
    >>
    >> There was a lot of feedback on the previous version (thanks!) so if I forgot
    >> to address some important point, please bring it to my attention again.
    >>
    >> Alexandre Courbot (3):
    >> Runtime Interpreted Power Sequences
    >> pwm_backlight: use power sequences
    >> tegra: add pwm backlight device tree nodes
    >
    > May I ask that the next version of this patchset be CCed to
    > linux-pm@vger.kernel.org?

    Will do.

    Alex.



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