Messages in this thread | | | Date | Tue, 21 Apr 2009 09:07:06 +0300 | From | Mike Rapoport <> | Subject | Re: [RFD] voltage/current regulator consumer interface |
| |
James Kosin wrote: > Mike Rapoport wrote: >> Hi, >> >> Recently there was a brief discussion on linux-arm-kernel list [1] about >> controlling voltage regulator state in cases when there is no consumer device >> for a particular regulator. >> >> I have some thoughts but I'd like to know people opinion before I start >> implementation. >> >> Problem >> ------- >> The regulator framework API provides ability to control the state of >> voltage/current regulators from within the kernel. Usually the regulator >> supplies power to a device and device driver or some hooks to the platform code >> from the device driver manipulate the regulator state. However, the regulator >> framework does not have userspace ABI that allows regulator state modifications. >> Lack of this ABI prevents fine-grained control for power consumption of devices >> such as GPS trancievers and GSM modems. Moreover, in SoC based systems it is >> possible to switch on/off power to entire subsystem when it is not used. >> > > > I'd also ask the question, Why? > If exposing to user space it leaves the possibility of damaging hardware > or completely frying a board.
Suppose you have a handheld device with GPS transceiver. You would like to give user the ability to switch the transceiver on and off.
> > James > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >
-- Sincerely yours, Mike.
| |