From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH 3/5] ARM: DT: tegra114:add aliases and DMA requestor for serial controller Date: Fri, 08 Mar 2013 11:40:38 -0700 Message-ID: <513A30A6.3040806@wwwdotorg.org> References: <1362750782-15174-1-git-send-email-ldewangan@nvidia.com> <1362750782-15174-4-git-send-email-ldewangan@nvidia.com> <513A25E4.8040504@wwwdotorg.org> <513A281B.9010702@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <513A281B.9010702-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Laxman Dewangan Cc: "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Peter De Schrijver List-Id: linux-tegra@vger.kernel.org On 03/08/2013 11:04 AM, Laxman Dewangan wrote: > On Friday 08 March 2013 11:24 PM, Stephen Warren wrote: >> On 03/08/2013 06:53 AM, Laxman Dewangan wrote: >>> Add APB DMA requestor and serial aliases for serial controller. >>> There will be two serial driver i.e. 8250 based simple serial driver >>> and APB DMA based serial driver for higher baudrate and performace. >>> >>> The simple serial driver get enabled with compatible nvidia,tegra20-uart >>> and APB DMA based driver will get enabled with compatible >>> nvidia,tegra30-hsuart. >>> diff --git a/arch/arm/boot/dts/tegra114.dtsi >>> b/arch/arm/boot/dts/tegra114.dtsi >>> + /* >>> + * There are two serial driver i.e. 8250 based simple serial >>> + * driver and APB DMA based serial driver for higher baudrate >>> + * and performace. To enable the 8250 based driver, the compatible >>> + * is "nvidia,tegra30-uart", "nvidia,tegra20-uart" and to enable >>> + * the APB DMA based serial driver, the comptible is >>> + * "nvidia,tegra30-hsuart", "nvidia,tegra20-hsuart". >>> + */ >> Any references to Tegra30 there should be changed to Tegra114 I think. > > Ok, there is not change on tegra30 and Tegra114, also we have not added > the tegra114 compatible in driver file. As I mentioned elsewhere, compatible must always include the most specific value; nvidia,tegra114-uart in this case. If the HW is backwards-compatible, then also include entries for the HW it's compatible with. Hence here, you want: compatible = "nvidia,tegra114-uart", "nvdia,tegra20-uart"; Since the compatible value here shouldn't include any Tegra30-related value, the comment shouldn't say that it should. Note that when there are multiple values in the compatible property, even if the driver doesn't know about the first value, it will still get matched based upon the 2nd/3rd/... value, so even though the driver doesn't explicitly know about nvidia,tegra114-uart, it will still get instantiated, because it does support nvdia,tegra20-uart. From mboxrd@z Thu Jan 1 00:00:00 1970 From: swarren@wwwdotorg.org (Stephen Warren) Date: Fri, 08 Mar 2013 11:40:38 -0700 Subject: [PATCH 3/5] ARM: DT: tegra114:add aliases and DMA requestor for serial controller In-Reply-To: <513A281B.9010702@nvidia.com> References: <1362750782-15174-1-git-send-email-ldewangan@nvidia.com> <1362750782-15174-4-git-send-email-ldewangan@nvidia.com> <513A25E4.8040504@wwwdotorg.org> <513A281B.9010702@nvidia.com> Message-ID: <513A30A6.3040806@wwwdotorg.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 03/08/2013 11:04 AM, Laxman Dewangan wrote: > On Friday 08 March 2013 11:24 PM, Stephen Warren wrote: >> On 03/08/2013 06:53 AM, Laxman Dewangan wrote: >>> Add APB DMA requestor and serial aliases for serial controller. >>> There will be two serial driver i.e. 8250 based simple serial driver >>> and APB DMA based serial driver for higher baudrate and performace. >>> >>> The simple serial driver get enabled with compatible nvidia,tegra20-uart >>> and APB DMA based driver will get enabled with compatible >>> nvidia,tegra30-hsuart. >>> diff --git a/arch/arm/boot/dts/tegra114.dtsi >>> b/arch/arm/boot/dts/tegra114.dtsi >>> + /* >>> + * There are two serial driver i.e. 8250 based simple serial >>> + * driver and APB DMA based serial driver for higher baudrate >>> + * and performace. To enable the 8250 based driver, the compatible >>> + * is "nvidia,tegra30-uart", "nvidia,tegra20-uart" and to enable >>> + * the APB DMA based serial driver, the comptible is >>> + * "nvidia,tegra30-hsuart", "nvidia,tegra20-hsuart". >>> + */ >> Any references to Tegra30 there should be changed to Tegra114 I think. > > Ok, there is not change on tegra30 and Tegra114, also we have not added > the tegra114 compatible in driver file. As I mentioned elsewhere, compatible must always include the most specific value; nvidia,tegra114-uart in this case. If the HW is backwards-compatible, then also include entries for the HW it's compatible with. Hence here, you want: compatible = "nvidia,tegra114-uart", "nvdia,tegra20-uart"; Since the compatible value here shouldn't include any Tegra30-related value, the comment shouldn't say that it should. Note that when there are multiple values in the compatible property, even if the driver doesn't know about the first value, it will still get matched based upon the 2nd/3rd/... value, so even though the driver doesn't explicitly know about nvidia,tegra114-uart, it will still get instantiated, because it does support nvdia,tegra20-uart. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760038Ab3CHSkm (ORCPT ); Fri, 8 Mar 2013 13:40:42 -0500 Received: from avon.wwwdotorg.org ([70.85.31.133]:43099 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759601Ab3CHSkk (ORCPT ); Fri, 8 Mar 2013 13:40:40 -0500 Message-ID: <513A30A6.3040806@wwwdotorg.org> Date: Fri, 08 Mar 2013 11:40:38 -0700 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: Laxman Dewangan CC: "linux-arm-kernel@lists.infradead.org" , "linux-tegra@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Peter De Schrijver Subject: Re: [PATCH 3/5] ARM: DT: tegra114:add aliases and DMA requestor for serial controller References: <1362750782-15174-1-git-send-email-ldewangan@nvidia.com> <1362750782-15174-4-git-send-email-ldewangan@nvidia.com> <513A25E4.8040504@wwwdotorg.org> <513A281B.9010702@nvidia.com> In-Reply-To: <513A281B.9010702@nvidia.com> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/08/2013 11:04 AM, Laxman Dewangan wrote: > On Friday 08 March 2013 11:24 PM, Stephen Warren wrote: >> On 03/08/2013 06:53 AM, Laxman Dewangan wrote: >>> Add APB DMA requestor and serial aliases for serial controller. >>> There will be two serial driver i.e. 8250 based simple serial driver >>> and APB DMA based serial driver for higher baudrate and performace. >>> >>> The simple serial driver get enabled with compatible nvidia,tegra20-uart >>> and APB DMA based driver will get enabled with compatible >>> nvidia,tegra30-hsuart. >>> diff --git a/arch/arm/boot/dts/tegra114.dtsi >>> b/arch/arm/boot/dts/tegra114.dtsi >>> + /* >>> + * There are two serial driver i.e. 8250 based simple serial >>> + * driver and APB DMA based serial driver for higher baudrate >>> + * and performace. To enable the 8250 based driver, the compatible >>> + * is "nvidia,tegra30-uart", "nvidia,tegra20-uart" and to enable >>> + * the APB DMA based serial driver, the comptible is >>> + * "nvidia,tegra30-hsuart", "nvidia,tegra20-hsuart". >>> + */ >> Any references to Tegra30 there should be changed to Tegra114 I think. > > Ok, there is not change on tegra30 and Tegra114, also we have not added > the tegra114 compatible in driver file. As I mentioned elsewhere, compatible must always include the most specific value; nvidia,tegra114-uart in this case. If the HW is backwards-compatible, then also include entries for the HW it's compatible with. Hence here, you want: compatible = "nvidia,tegra114-uart", "nvdia,tegra20-uart"; Since the compatible value here shouldn't include any Tegra30-related value, the comment shouldn't say that it should. Note that when there are multiple values in the compatible property, even if the driver doesn't know about the first value, it will still get matched based upon the 2nd/3rd/... value, so even though the driver doesn't explicitly know about nvidia,tegra114-uart, it will still get instantiated, because it does support nvdia,tegra20-uart.