On 01 April 2017 @20:59, Eduardo Valentin wrote: > Subject: Re: [PATCH V7 6/7] thermal: da9062/61: Thermal junction temperature monitoring driver > > On Tue, Mar 28, 2017 at 03:43:33PM +0100, Steve Twiss wrote: > > From: Steve Twiss <stwiss.opensource@xxxxxxxxxxx> > > > > Add junction temperature monitoring supervisor device driver, compatible > > with the DA9062 and DA9061 PMICs. A MODULE_DEVICE_TABLE() macro is added. > > > > If the PMIC's internal junction temperature rises above T_WARN (125 degC) > > an interrupt is issued. This T_WARN level is defined as the > > THERMAL_TRIP_HOT trip-wire inside the device driver. > > > > The thermal triggering mechanism is interrupt based and happens when the > > temperature rises above a given threshold level. The component cannot > > return an exact temperature, it only has knowledge if the temperature is > > above or below a given threshold value. A status bit must be polled to > > detect when the temperature falls below that threshold level again. A > > kernel work queue is configured to repeatedly poll and detect when the > > temperature falls below this trip-wire, between 1 and 10 second intervals > > (defaulting at 3 seconds). > > > > This scheme is provided as an example. It would be expected that any > > final implementation will also include a notify() function and any of these > > settings could be altered to match the application where appropriate. > > > > When over-temperature is reached, the interrupt from the DA9061/2 will be > > repeatedly triggered. The IRQ is therefore disabled when the first > > over-temperature event happens and the status bit is polled using a > > work-queue until it becomes false. > > > > This strategy is designed to allow the periodic transmission of uevents > > (HOT trip point) as the first level of temperature supervision method. It > > is intended for non-invasive temperature control, where the necessary > > measures for cooling the system down are left to the host software. Once > > the temperature falls again, the IRQ is re-enabled so a new critical > > over-temperature event can be detected. > > > > Reviewed-by: Lukasz Luba <lukasz.luba@xxxxxxx> > > Signed-off-by: Steve Twiss <stwiss.opensource@xxxxxxxxxxx> > > I have had a look on the history of this driver on its previous > versions, and I do not think I have any other point to request on it. Thank you. > Obviously, I still need to state that I do not like its oddness as it is > not really benefiting much of the thermal control implemented on the > thermal subsystem. Agreed. But, it should be useful in the case of an over-temperature in the system PMIC when the OS needs to be notified to bring core temperature under control. > What is the plan for this series? Am I expected to get this driver > through thermal tree ? Or is this series going into a one shot? > > If option 1 is the expected, would the driver need to get its > mfd parent merged first? Other components such as the ONKEY and Watchdog have not required the MFD to be merged first. I don't see any strong dependency for the MFD to exist with this thermal component. I'm not sure how much Lee is waiting for Acks to exist before proceeding with the MFD. I have TO:'d Lee Jones, for this case. Regards, Steve -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
