Re: [PATCH] serial: 8250_dw: Handle no_console_suspend when uart loses state

From: Loic Poulain
Date: Mon Nov 17 2014 - 03:53:32 EST

In certain suspend modes on certain boards the 8250 UART may lose
state when the device goes to suspend. If we're using
no_console_suspend this can cause lots of problems during resume.

Let's cache the basic UART config registers at suspend time and if we
notice that the UART loses state (by looking at a canary stored in the
scratch register) we'll restore it.

If I'm not wrong, it's already done in acpi_lpss suspend/resume (for 8250_dw).
Commit c78b0830667a7e7c1f0ca65b76b33166a84806b3.


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