Re: [PATCH 4/5] tty: serial: 8250 core: add runtime pm

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 07/16/2014 12:06 PM, Felipe Balbi wrote:
On Wed, Jul 16, 2014 at 05:54:56PM +0200, Sebastian Andrzej Siewior wrote:
On 07/16/2014 05:16 PM, Felipe Balbi wrote:

I wonder if you should get_sync() on start_tx() and only
put_autosuspend() at stop_tx(). I guess the outcome would be
largely the same, no ?

I just opened minicom on ttyS0 and gave a try. start_tx() was invoked
each time I pressed a key (sent a character). I haven't seen stop_tx()
even after after I closed minicom. I guess stop_tx() is invoked if you
switch half-duplex communication.

that's bad, I expected stop to be called also after each character.

The 8250 core auto-stops tx when the tx ring buffer is empty (except
in the case of dma, where stopping tx isn't necessary).

Regards,
Peter Hurley
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux