On Thu, 2012-09-13 at 09:18 +0200, Sascha Hauer wrote: > On Thu, Sep 13, 2012 at 10:03:27AM +0300, Tomi Valkeinen wrote: > > On Thu, 2012-09-13 at 09:00 +0200, Sascha Hauer wrote: > > > On Thu, Sep 13, 2012 at 09:54:09AM +0300, Tomi Valkeinen wrote: > > > > On Thu, 2012-09-13 at 15:36 +0900, Alex Courbot wrote: > > > > > On Thursday 13 September 2012 14:22:57 Tomi Valkeinen wrote: > > > > > > > > > > > However, I fear these board specific things may be quite a bit anything, > > > > > > so it may well be pwm, gpios and regulators are not enough for them. For > > > > > > example, there could be an FPGA on the board which requires some > > > > > > configuration to accomplish the task at hand. It could be rather > > > > > > difficult to handle it with a generic power sequence. > > > > > > > > > > Right. Note that this framework is supposed to be extended - I would like to > > > > > at least add regulator voltage setting, and maybe even support for clocks and > > > > > pinmux (but that might be out of place). > > > > > > > > Yes, that's one concern of mine... I already can imagine someone > > > > suggesting adding conditionals to the power sequence data. Perhaps also > > > > direct memory read/writes so you can twiddle registers directly. > > These memory writes can be avoided when these registers are abstracted > as a regular gpio/regulator/pwm driver. Only if they are gpios/regulators/pwms. Yes, I agree most of the possible things to configure would be among those (or perhaps pinmuxing). But there's always the odd one that's not one of those. > > Do you have examples of board specific power sequences or such? > > Sure, tons of. One board needs a gpio to be set high to enable backlight, > the next one to low, a regulator has to be enabled, and to avoid > flickering a certain timing has to be ensured. This is all highly board > specific. Okay. In my experience these have always been device specific. In the case of backlight, the backlight device requires one gpio to be set high, other one low, etc. Can you share a bit more what kind of HW configuration you have that requires this? The backlight is not a single piece of HW added to the board (or embedded into a panel module), but consists of multiple HW blocks integrated in a custom way to the board? Tomi
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