On Thu, Aug 18, 2011 at 5:00 AM, Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > On Wed, 2011-08-17 at 15:17 +0200, Linus Walleij wrote: >> On Wed, Aug 17, 2011 at 3:04 PM, Mark Brown >> <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > >> > The device driver will know what power supplies and other signals the >> > device has, and it will know how and when to use them. (...) > >> And I guess there is nothing in the spec claiming that all devices >> be powered-on when you boot? > > I don't believe so, and if there were I'd not expect anyone to pay a > blind bit of notice to it. That means that the regulators handling the slimbus devices will need to be enabled before the drivers issue regulator_get() and regulator_enable() on them. Does the regulator constraint .always_on have this semantic effect, so the regulator framework can power up the devices without their drivers claiming the regulators first? Or would we need a new .boot_enable flag to handle that? > If my memory serves (I don't have access to the relevant documents right > now) the device announces itself when it detects that the bus is alive. > Slimbus is a relatively heavyweight interface so the extra cost of doing > this won't be too bad. OK so if we can just power the device the bus can probably autodetect all devices on it, it seems. Thanks, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
