Messages in this thread | | | Subject | Re: [alsa-devel] [PATCH v6 02/11] mfd: wcd934x: add support to wcd9340/wcd9341 codec | From | Pierre-Louis Bossart <> | Date | Fri, 20 Dec 2019 09:22:48 -0600 |
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>>> Note these are the child devices of the MFD SLIMBus device. >> >> Ah ok. I guess the creation of those child devices when the parent >> SLIMbus device reports PRESENT initially if fine, it's the part where >> you remove them if the device loses sync or gets powered off which is >> odd. And I guess technically you could still have race conditions >> where a child device starts a transaction just as the parent is no >> longer attached to the bus. > > Losing power to SLIMBus device is very odd usecase and if it happens > suggests that threre are bigger issues on the board design itself. This > case should never happen. Even if it happens we would get timeout errors > on every SLIMbus transactions. > >> >>>> I would however not remove the devices when the status is down but >>>> only on an explicit .remove. >>> >>> Am open for suggestions but I would not like the child devices to >>> talk on the bus once the SLIMbus device is down! Only way to ensure >>> or make it silent is to remove. >> >> it's as if you are missing a mechanism to forward the parent status to >> the children so use remove() for lack of a better solution? > That is true. This gives bit more control on the slave device lifecycle. > Current solution works fine for now with less complexities across > multiple drivers. I also agree that there is scope of improvement in > future for this.
ok, makes sense, thanks for the answers. No further questions, so
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
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