Messages in this thread | | | Date | Wed, 16 Jul 2014 18:40:01 +0200 | From | Sebastian Andrzej Siewior <> | Subject | Re: [PATCH 4/5] tty: serial: 8250 core: add runtime pm |
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On 07/16/2014 06:06 PM, Felipe Balbi wrote:
>>> well, other than in probe and other functions which need to >>> make sure clocks are on, but it seems unnecessary to >>> enable/disable in every function. >> >> What do you have in mind? Do you plan to let the uart on while >> the minicom is attached but is doing nothing? In that case, >> ->startup() and ->shutdown() should be enough. > > no the idea was to keep it on for as long as it's transferring > characters and idle it otherwise, if that can't be done easily, > then I guess your way is the only way.
But maybe we have to add some additional logic here to keep it up for the transfer. I've been just (maybe over)thinking: If you send 300 bytes over DMA via 300 baud it should take 10 seconds. The PM-timeout could hit before the transfer is complete. Same thing with hw-flowcontrol where you could get stalled for a few seconds. However it doesn't seem to be a problem in current omap-serial driver.
> cheers
Sebastian
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