serial-core: reset the console speed on resume
On some platforms, we need to restore the console speed on resume even it was not suspended (no_console_suspend), and on others we don't have to do that. So don't care about the "console_suspend_enabled" and unconditionally reset the console speed if it is a console. This is actually a redo of ba15ab0e (Set proper console speed on resume if console suspend is disabled) from Deepak Saxena. I also tried to investigate more to find out if this change will break others, here is what I've found out: commit 891b9dd1 Author: Jason Wang <jason77.wang@gmail.com> serial-core: restore termios settings when resume console ports commit ca2e71aa Author: Jason Wang <jason77.wang@gmail.com> serial-core: skip call set_termios/console_start when no_console_suspend commit 4547be78 Author: Stanislav Brabec <sbrabec@suse.cz> serial-core: resume serial hardware with no_console_suspend commit ba15ab0e Author: Deepak Saxena <dsaxena@laptop.org> Set proper console speed on resume if console suspend is disabled from ba15ab0e, we learned that, even if the console suspend is disabled (when no_console_suspend is set), we may still need to "reset the port to the state it was in before we suspended." Then with 4547be78, this piece of code is removed. And then Jason Wang added that back in ca2e71aa and 891b9dd1, to fix some breakage on OMAP3EVM platform. From ca2e71aa we learned that the "set_termios" things is actually needed by both console is suspended and not suspended. That's why I removed the console_suspended_enabled condition, and only call console_start() when we actually suspeneded it. I also noticed in this thread: http://marc.info/?t=129079257100004&r=1&w=2 , which talked about on some platforms, UART HW will be cut power whether or not we set no_console_suspend, and then on resume it does not work quite well. I have a similar HW, and this patch fixed this issue, don't know if this patch also works on their platforms. [Update: Stanislav tested this patch on Zaurus and reported it improves the situation. Thanks.] CC: Greg KH <greg@kroah.com> CC: Deepak Saxena <dsaxena@laptop.org> CC: Jason Wang <jason77.wang@gmail.com> CC: Stanislav Brabec <sbrabec@suse.cz> CC: Daniel Drake <dsd@laptop.org> Signed-off-by: Yin Kangkai <kangkai.yin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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