From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCHv1 1/3] OMAP UART: Adds omap-serial driver support. Date: Fri, 9 Oct 2009 10:46:36 -0700 Message-ID: <20091009174635.GH25892@atomide.com> References: <65168.192.168.10.89.1253788033.squirrel@dbdmail.itg.ti.com> <20091007215116.GB29320@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mho-02-ewr.mailhop.org ([204.13.248.72]:54624 "EHLO mho-02-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933772AbZJIRrW (ORCPT ); Fri, 9 Oct 2009 13:47:22 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "G, Manjunath Kondaiah" Cc: Govindraj , "Raja, Govindraj" , "linux-omap@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-serial@vger.kernel.org" * G, Manjunath Kondaiah [091008 00:41]: >=20 > Govind, > > -----Original Message----- > > From: linux-omap-owner@vger.kernel.org=20 > > [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;=20 > > linux-kernel@vger.kernel.org; linux-serial@vger.kernel.org > > Subject: Re: [PATCHv1 1/3] OMAP UART: Adds omap-serial driver suppo= rt. > >=20 > > On Thu, Oct 8, 2009 at 3:21 AM, Tony Lindgren=20 > > wrote: > > > * Govindraj.R [090924 03:29]: > > >> From: Govindraj R > > >> > > >> This patch adds support for OMAP3430-HIGH SPEED UART Controller. > > >> > > >> Signed-off-by: =A0 =A0 =A0 =A0Govindraj R > > >> Reviewed-by: Alan Cox > > >> Reviewed-by: Tony Lindgren > > > > > > You should only add Reviewed-by if Alan or me have replied with i= t. > > > > > > 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 > > >> =A0 =A0 =A0 =A0 Currently, only 8250 compatible ports are suppor= ted, but > > >> =A0 =A0 =A0 =A0 others can easily be added. > > >> > > >> +config SERIAL_OMAP > > >> + =A0 =A0 bool "OMAP serial port support" > > >> + =A0 =A0 depends on ARM && ARCH_OMAP > > >> + =A0 =A0 select SERIAL_CORE > > >> + =A0 =A0 help > > >> + =A0 =A0 If you have a machine based on an Texas Instruments=20 > > OMAP CPU you > > >> + =A0 =A0 can enable its onboard serial ports by enabling this o= ption. > > >> + > > >> +config SERIAL_OMAP_CONSOLE > > >> + =A0 =A0 bool "Console on OMAP serial port" > > >> + =A0 =A0 depends on SERIAL_OMAP > > >> + =A0 =A0 select SERIAL_CORE_CONSOLE > > >> + =A0 =A0 help > > >> + =A0 =A0 If you have enabled the serial port on the Texas=20 > > Instruments OMAP > > >> + =A0 =A0 CPU you can make it the console by answering Y to=20 > > this option. > > >> + > > >> + =A0 =A0 Even if you say Y here, the currently visible virtual = console > > >> + =A0 =A0 (/dev/tty0) will still be used as the system console=20 > > by default, but > > >> + =A0 =A0 you can alter that using a kernel command line option = such as > > >> + =A0 =A0 "console=3DttyS0". (Try "man bootparam" or see the=20 > > documentation of > > >> + =A0 =A0 your boot loader (lilo or loadlin) about how to pass=20 > > options to the > > >> + =A0 =A0 kernel at boot time.) > > >> + > > >> +config SERIAL_OMAP_DMA_UART1 > > >> + =A0 =A0 bool "UART1 DMA support" > > >> + =A0 =A0 depends on SERIAL_OMAP > > >> + =A0 =A0 help > > >> + =A0 =A0 If you have enabled the serial port on the Texas=20 > > Instruments OMAP > > >> + =A0 =A0 CPU you can enable the DMA transfer on UART 1 by answe= ring > > >> + =A0 =A0 to this option. > > >> + > > >> +config SERIAL_OMAP_DMA_UART2 > > >> + =A0 =A0 bool "UART2 DMA support" > > >> + =A0 =A0 depends on SERIAL_OMAP > > >> + =A0 =A0 help > > >> + =A0 =A0 If you have enabled the serial port on the Texas=20 > > Instruments OMAP > > >> + =A0 =A0 CPU you can enable the DMA transfer on UART 2 by answe= ring > > >> + =A0 =A0 to this option. > > >> + > > >> +config SERIAL_OMAP_DMA_UART3 > > >> + =A0 =A0 bool "UART3 DMA support" > > >> + =A0 =A0 depends on SERIAL_OMAP > > >> + =A0 =A0 help > > >> + =A0 =A0 If you have enabled the serial port on the Texas=20 > > Instruments OMAP > > >> + =A0 =A0 CPU you can enable the DMA transfer on UART 3 by answe= ring > > >> + =A0 =A0 to this option. > > >> + > > >> =A0config SERIAL_OF_PLATFORM_NWPSERIAL > > >> =A0 =A0 =A0 tristate "NWP serial port driver" > > >> =A0 =A0 =A0 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 fil= es. > > > > > > This is the third time I'm commenting on the same issue! > > > > > > What's the point of posting these patches for review if the issue= s > > > don't get solved? > >=20 > >=20 > > 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 cons= ole > > then interrupt mode will do, else if used with bluetooth which does > > huge data transfer then DMA mode can be selected. > >=20 > > 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 over= ride vith a kernel cmdline option. That's because we support compiling in an= d 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? > Usage of UART is board dependent. It's usage will not change dynamica= lly for > a given board. This can be removed from Kconfig and move it to respec= tive=20 > 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" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html