From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Nikula Subject: Re: [RFC] serial: omap-serial: Enable the UART wake-up bits always Date: Fri, 4 Feb 2011 17:47:01 +0200 Message-ID: <20110204174701.4dcf290a.jhnikula@gmail.com> References: <1295884282-16562-1-git-send-email-jhnikula@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1295884282-16562-1-git-send-email-jhnikula@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-omap@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Tony Lindgren , "Govindraj.R" List-Id: linux-omap@vger.kernel.org On Mon, 24 Jan 2011 17:51:22 +0200 Jarkko Nikula 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 > Cc: Govindraj.R > --- > 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