[PATCH 4/5] tty: serial: 8250 core: add runtime pm
From: bigeasy@linutronix.de (Sebastian Andrzej Siewior)
Date: 2014-07-16 16:40:50
Also in:
linux-omap, linux-serial, lkml
From: bigeasy@linutronix.de (Sebastian Andrzej Siewior)
Date: 2014-07-16 16:40:50
Also in:
linux-omap, linux-serial, lkml
On 07/16/2014 06:06 PM, Felipe Balbi wrote:
quoted
quoted
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