From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936454AbcCQVai (ORCPT ); Thu, 17 Mar 2016 17:30:38 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:34801 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933278AbcCQVae (ORCPT ); Thu, 17 Mar 2016 17:30:34 -0400 Subject: Re: [PATCH 4/5] pwm: pwm-tipwmss: Update documentation to use empty range property To: Rob Herring References: <1457380318-15452-1-git-send-email-fcooper@ti.com> <1457380318-15452-5-git-send-email-fcooper@ti.com> <20160317150140.GA25775@rob-hp-laptop> <56EAE1BD.9040601@ti.com> CC: , , , , , , , , , , , , , , , , From: "Franklin S Cooper Jr." Message-ID: <56EB21C3.8000806@ti.com> Date: Thu, 17 Mar 2016 16:29:39 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56EAE1BD.9040601@ti.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/17/2016 11:56 AM, Franklin S Cooper Jr. wrote: > > On 03/17/2016 10:01 AM, Rob Herring wrote: >> On Mon, Mar 07, 2016 at 01:51:57PM -0600, Franklin S Cooper Jr wrote: >>> Since the PWMSS and its subdevices (eCAP and ePWM) use the same address >>> space then the range property should be empty. Update the documentation >>> to show the correct usage. >> Why does it matter? An empty ranges is generally not preferred. > Someone pointed out that ranges should probably be empty. I > double checked it with what is in the ePAPR doc and based on > the definition it should be set to empty. I also checked > against the am33xx.dtsi and saw that both USB and ethernet > uses an empty value for ranges. > > Can you elaborate on why this isn't preferable? I'm going to drop this patch and the previous patch for now that messes with the ranges property. I can resubmit them separately later on if that is the route we decide to take. > >>> Signed-off-by: Franklin S Cooper Jr >>> --- >>> Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt | 12 ++++-------- >>> 1 file changed, 4 insertions(+), 8 deletions(-) >>> >>> diff --git a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >>> index f7eae77..672fa71 100644 >>> --- a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >>> +++ b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt >>> @@ -7,11 +7,9 @@ Required properties: >>> Should set to 1. >>> - size-cells: specify number of u32 entries needed to specify child nodes size >>> in reg property. Should set to 1. >>> -- ranges: describes the address mapping of a memory-mapped bus. Should set to >>> - physical address map of child's base address, physical address within >>> - parent's address space and length of the address map. For am33xx, >>> - 3 set of child register maps present, ECAP register space, EQEP >>> - register space, EHRPWM register space. >>> +- ranges: describes the address mapping of a memory-mapped bus. Its value >>> + should be empty since no address translation is needed between the >>> + parent and the child. >>> >>> Also child nodes should also populated under PWMSS DT node. >>> >>> @@ -23,9 +21,7 @@ pwmss0: pwmss@48300000 { >>> #address-cells = <1>; >>> #size-cells = <1>; >>> status = "disabled"; >>> - ranges = <0x48300100 0x48300100 0x80 /* ECAP */ >>> - 0x48300180 0x48300180 0x80 /* EQEP */ >>> - 0x48300200 0x48300200 0x80>; /* EHRPWM */ >>> + ranges; >>> >>> /* child nodes go here */ >>> }; >>> -- >>> 2.7.0 >>> > -- > 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