Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933361AbZJMGyr (ORCPT ); Tue, 13 Oct 2009 02:54:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933214AbZJMGyq (ORCPT ); Tue, 13 Oct 2009 02:54:46 -0400 Received: from mail-ew0-f208.google.com ([209.85.219.208]:43140 "EHLO mail-ew0-f208.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933148AbZJMGyo convert rfc822-to-8bit (ORCPT ); Tue, 13 Oct 2009 02:54:44 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=nn55SOOHdftiJNQJHeRUforjLcuVr4Msva8pqva64uExgcZdV6SwE7hky17La1CAAC 6PYJJkRYfFoJCMCUhSNIUZ6gnt9ubMHHvyRxDxqNTyvdI+usgy9UID8kvr0ceGUiINGj 27NFGTZIBrlsH1hoA9cUYlY8HGLBw+c2qzAtQ= MIME-Version: 1.0 In-Reply-To: <20091009174635.GH25892@atomide.com> References: <65168.192.168.10.89.1253788033.squirrel@dbdmail.itg.ti.com> <20091007215116.GB29320@atomide.com> <20091009174635.GH25892@atomide.com> Date: Tue, 13 Oct 2009 12:24:06 +0530 Message-ID: <7f9d1ffb0910122354o64b5aa01l3fe33ab78dfb5f23@mail.gmail.com> Subject: Re: [PATCHv1 1/3] OMAP UART: Adds omap-serial driver support. From: kishore kadiyala To: Tony Lindgren Cc: "G, Manjunath Kondaiah" , Govindraj , "Raja, Govindraj" , "linux-omap@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-serial@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6086 Lines: 155 Tony, On Fri, Oct 9, 2009 at 11:16 PM, Tony Lindgren wrote: > * G, Manjunath Kondaiah [091008 00:41]: >> >> Govind, >> > -----Original Message----- >> > From: linux-omap-owner@vger.kernel.org >> > [mailto:linux-omap-owner@vger.kernel.org] On Behalf Of Govindraj >> > Sent: Thursday, October 08, 2009 11:44 AM >> > To: Tony Lindgren >> > Cc: Raja, Govindraj; linux-omap@vger.kernel.org; >> > linux-kernel@vger.kernel.org; linux-serial@vger.kernel.org >> > Subject: Re: [PATCHv1 1/3] OMAP UART: Adds omap-serial driver support. >> > >> > On Thu, Oct 8, 2009 at 3:21 AM, Tony Lindgren >> > wrote: >> > > * Govindraj.R [090924 03:29]: >> > >> From: Govindraj R >> > >> >> > >> This patch adds support for OMAP3430-HIGH SPEED UART Controller. >> > >> >> > >> Signed-off-by: ? ? ? ?Govindraj R >> > >> Reviewed-by: Alan Cox >> > >> Reviewed-by: Tony Lindgren >> > > >> > > You should only add Reviewed-by if Alan or me have replied with it. >> > > >> > > So far I've only replied with some comments that have not yet >> > > been fixed, so we're few more steps from being Reviewd-by. >> > > >> > > >> > > >> > >> diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig >> > >> index 6553833..67a7129 100644 >> > >> --- a/drivers/serial/Kconfig >> > >> +++ b/drivers/serial/Kconfig >> > >> @@ -1359,6 +1359,53 @@ config SERIAL_OF_PLATFORM >> > >> ? ? ? ? Currently, only 8250 compatible ports are supported, but >> > >> ? ? ? ? others can easily be added. >> > >> >> > >> +config SERIAL_OMAP >> > >> + ? ? bool "OMAP serial port support" >> > >> + ? ? depends on ARM && ARCH_OMAP >> > >> + ? ? select SERIAL_CORE >> > >> + ? ? help >> > >> + ? ? If you have a machine based on an Texas Instruments >> > OMAP CPU you >> > >> + ? ? can enable its onboard serial ports by enabling this option. >> > >> + >> > >> +config SERIAL_OMAP_CONSOLE >> > >> + ? ? bool "Console on OMAP serial port" >> > >> + ? ? depends on SERIAL_OMAP >> > >> + ? ? select SERIAL_CORE_CONSOLE >> > >> + ? ? help >> > >> + ? ? If you have enabled the serial port on the Texas >> > Instruments OMAP >> > >> + ? ? CPU you can make it the console by answering Y to >> > this option. >> > >> + >> > >> + ? ? Even if you say Y here, the currently visible virtual console >> > >> + ? ? (/dev/tty0) will still be used as the system console >> > by default, but >> > >> + ? ? you can alter that using a kernel command line option such as >> > >> + ? ? "console=ttyS0". (Try "man bootparam" or see the >> > documentation of >> > >> + ? ? your boot loader (lilo or loadlin) about how to pass >> > options to the >> > >> + ? ? kernel at boot time.) >> > >> + >> > >> +config SERIAL_OMAP_DMA_UART1 >> > >> + ? ? bool "UART1 DMA support" >> > >> + ? ? depends on SERIAL_OMAP >> > >> + ? ? help >> > >> + ? ? If you have enabled the serial port on the Texas >> > Instruments OMAP >> > >> + ? ? CPU you can enable the DMA transfer on UART 1 by answering >> > >> + ? ? to this option. >> > >> + >> > >> +config SERIAL_OMAP_DMA_UART2 >> > >> + ? ? bool "UART2 DMA support" >> > >> + ? ? depends on SERIAL_OMAP >> > >> + ? ? help >> > >> + ? ? If you have enabled the serial port on the Texas >> > Instruments OMAP >> > >> + ? ? CPU you can enable the DMA transfer on UART 2 by answering >> > >> + ? ? to this option. >> > >> + >> > >> +config SERIAL_OMAP_DMA_UART3 >> > >> + ? ? bool "UART3 DMA support" >> > >> + ? ? depends on SERIAL_OMAP >> > >> + ? ? help >> > >> + ? ? If you have enabled the serial port on the Texas >> > Instruments OMAP >> > >> + ? ? CPU you can enable the DMA transfer on UART 3 by answering >> > >> + ? ? to this option. >> > >> + >> > >> ?config SERIAL_OF_PLATFORM_NWPSERIAL >> > >> ? ? ? tristate "NWP serial port driver" >> > >> ? ? ? depends on PPC_OF && PPC_DCR >> > > >> > > There's absolutely no need for having Kconfig options for the DMA >> > > support. Please pass that in platform_data from the board-*.c files. >> > > >> > > This is the third time I'm commenting on the same issue! >> > > >> > > What's the point of posting these patches for review if the issues >> > > don't get solved? >> > >> > >> > The omap-serial uart driver is designed to work either in interrupt >> > mode or in DMA mode, >> > We have provided this option so that one can select interrupt mode or >> > DMA mode based on the uart usage, if somebody is using uart as console >> > then interrupt mode will do, else if used with bluetooth which does >> > huge data transfer then DMA mode can be selected. >> > >> > Don't you think this should be a configurable option using kconfig >> > rather than passing as platform data? > > Nope. I think it should be platform_data and should be possible to override > vith a kernel cmdline option. That's because we support compiling in and > booting many boards the same kernel binary. > >> > if used as platform data then one has to modify platform data to >> > switch between the interrupt and DMA mode. > > How about set some kernel cmdline options if you want to override the > default settings? Using cmdline options, will make specific UART switch dynamically between Non-DMA and DMA mode which is not handled in the driver. how abt using bootargs to share this Mode info ? > >> Usage of UART is board dependent. It's usage will not change dynamically for >> a given board. This can be removed from Kconfig and move it to respective >> board file-> board-*.c > > Or can be changed from kernel cmdline if necessary. > > Regards, > > Tony > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at ?http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/