Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756803AbaFYXPB (ORCPT ); Wed, 25 Jun 2014 19:15:01 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:53733 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751598AbaFYXO6 (ORCPT ); Wed, 25 Jun 2014 19:14:58 -0400 Message-ID: <53AB57ED.7080600@wwwdotorg.org> Date: Wed, 25 Jun 2014 17:14:53 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Andrew Bresticker CC: devicetree@vger.kernel.org, linux-doc@vger.kernel.org, "linux-tegra@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , linux-usb@vger.kernel.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Randy Dunlap , Thierry Reding , Russell King , Linus Walleij , Greg Kroah-Hartman , Mathias Nyman , Grant Likely , Alan Stern , Kishon Vijay Abraham I , Arnd Bergmann Subject: Re: [PATCH v1 5/9] of: Add NVIDIA Tegra XHCI controller binding References: <1403072180-4944-1-git-send-email-abrestic@chromium.org> <1403072180-4944-6-git-send-email-abrestic@chromium.org> <53AB4530.2050106@wwwdotorg.org> In-Reply-To: X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/25/2014 05:02 PM, Andrew Bresticker wrote: > On Wed, Jun 25, 2014 at 2:54 PM, Stephen Warren wrote: >> On 06/18/2014 12:16 AM, Andrew Bresticker wrote: >>> Add device-tree binding documentation for the XHCI controller present >>> on Tegra124 and later SoCs. >> >>> diff --git a/Documentation/devicetree/bindings/usb/nvidia,tegra124-xhci.txt b/Documentation/devicetree/bindings/usb/nvidia,tegra124-xhci.txt >> >>> + - clock-names: Must include the following entries: >>> + - xusb_host >>> + - xusb_falcon_src >>> + - xusb_ss >>> + - xusb_ss_src >>> + - xusb_hs_src >>> + - xusb_fs_src >> >> Looking at include/dt-bindings/clock/tegra124-car.h I see a few entries >> potentially missing here: >> >> #define TEGRA124_CLK_XUSB_HOST_SRC 252 >> #define TEGRA124_CLK_XUSB_DEV_SRC 256 >> #define TEGRA124_CLK_XUSB_DEV 257 >> #define TEGRA124_CLK_XUSB_SS_DIV2 312 > > The driver doesn't use them, so I didn't put them in the binding. I think we should add them in case we need them later. Best to fully describe the HW rather than the parts of the HW that SW currently uses. >>> + - pll_u_480m >> >> Not just pll_u? > > We specifically want pll_u_480M as that's what we use as the parent of > xusb_ss_src when scaling it to 120Mhz. OK. I recall text in the TRM implying that SW should just leave PLL_U alone and not fiddle with the separate output clocks. Still, if we have a clock ID for each output, and it's the correct parent for the clock, then it does make sense to use that ID. -- 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/