From mboxrd@z Thu Jan  1 00:00:00 1970
From: Felipe Balbi <balbi@ti.com>
Subject: Re: [RFC v2]: Issues implementing clock handling mechanism within
 UART driver
Date: Fri, 29 Jul 2011 12:55:13 +0300
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To: "Govindraj.R" <govindraj.raja@ti.com>
Cc: linux-omap@vger.kernel.org, linux-serial@vger.kernel.org, linux-pm@lists.linux-foundation.org, "Rafael J. Wysocki" <rjw@sisk.pl>, Paul Walmsley <paul@pwsan.com>, Kevin Hilman <khilman@ti.com>, Vishwanath Sripathy <vishwanath.bs@ti.com>, Partha Basak <p-basak2@ti.com>, Felipe Balbi <balbi@ti.com>, Santosh Shilimkar <santosh.shilimkar@ti.com>, Rajendra Nayak <rnayak@ti.com>, Benoit Cousson <b-cousson@ti.com>, Tero Kristo <t-kristo@ti.com>
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Hi,

On Thu, Jul 28, 2011 at 02:59:55PM +0530, Govindraj.R wrote:
> Proposal:
> --------
> 	1. For the UART, follow the current approach of locking the console in
> 	   Idle/Suspend path before cutting the clock but using pm_runtime_putsy=
nc.
> 	   That is, continue using the prepare/resume Idle calls in idle path.

I believe you should be using ->prepare() to prevent that any other
work on UART won't trigger a console_write() right now. Maybe only
queueing the work for after ->complete() or, maybe, just ignoring the
work and loosing some prints, dunno.

> 	2. Other Approach would be adding conditions to debug prints from
> 	   omap_device/ omap_hwmod/clock_framework avoid calling these debug
> 	   prints for uart.
> 	   Or Even a debug macro that would not debug prints if the context is
> 	   from uart.

yeah, that might work but then again, if we were using 8250.c, would we
have this limitation ??

I think that, maybe, your best call would be to capture console_write()
calls into an internal temporary buffer on ->prepare() and flush it once
->complete() is called ?

BTW, where are the patches ? :-)

--=20
balbi

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