linux-kernel - Re: [RFC] serial: omap-serial: Enable the UART wake-up bits always

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Fri, 4 Feb 2011 17:47:01 +0200
From:	Jarkko Nikula <jhnikula@...il.com>
To:	linux-omap@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, Greg Kroah-Hartman <gregkh@...e.de>,
	Tony Lindgren <tony@...mide.com>,
	"Govindraj.R" <govindraj.raja@...com>
Subject: Re: [RFC] serial: omap-serial: Enable the UART wake-up bits always

On Mon, 24 Jan 2011 17:51:22 +0200
Jarkko Nikula <jhnikula@...il.com> wrote:

> OMAP can do also dynamic idling so wake-up enable register should be set
> also while system is running. If UART_OMAP_WER is not set, then for instance
> the RX activity cannot wake up the UART port that is sleeping.
> 
> This RX wake-up feature was working when the 8250 driver was used instead
> of omap-serial. Reason for this is that the 8250 doesn't set the
> UART_OMAP_WER and then arch/arm/mach-omap2/pm34xx.c ends up saving and
> restoring the reset default which is the same than value
> OMAP_UART_WER_MOD_WKUP here.
> 
> Fix this by moving the conditional UART_OMAP_WER write from serial_omap_pm
> into serial_omap_startup where wake-up bits are set unconditionally.
> 
> Signed-off-by: Jarkko Nikula <jhnikula@...il.com>
> Cc: Govindraj.R <govindraj.raja@...com>
> ---
> This problem has been here since 2.6.37 when the omap-serial was switched
> into use so this patch is for 2.6.39.
> ---
For omap folks:

1. This patch is coming through tty tree
http://git.kernel.org/?p=linux/kernel/git/gregkh/tty-2.6.git;a=commit;h=78841462d72fe7038cb7ea48adecc6fc395f2dc5

2. This patch helps those boards that don't have UART RTS signal (e.g.
BeagleBoard) and thus padconf wakeup mechanism is not available.

-- 
Jarkko
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/