From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomi Valkeinen Subject: Re: OMAP4 DSS clock setup Date: Mon, 11 Apr 2011 12:05:00 +0300 Message-ID: <1302512700.2198.53.camel@deskari> References: <1301467733.2333.83.camel@deskari> <4D92F899.7010606@ti.com> <1301483027.4045.16.camel@deskari> <4D931E21.8090305@ti.com> <1301489930.15095.51.camel@deskari> <1301900022.2715.12.camel@deskari> <1302241893.2102.21.camel@deskari> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from na3sys009aog105.obsmtp.com ([74.125.149.75]:39098 "EHLO na3sys009aog105.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751339Ab1DKJFG (ORCPT ); Mon, 11 Apr 2011 05:05:06 -0400 Received: by fxm3 with SMTP id 3so5371360fxm.16 for ; Mon, 11 Apr 2011 02:05:03 -0700 (PDT) In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Paul Walmsley Cc: "Cousson, Benoit" , "Semwal, Sumit" , "Taneja, Archit" , linux-omap On Fri, 2011-04-08 at 08:55 -0600, Paul Walmsley wrote: > Hi > > On Fri, 8 Apr 2011, Tomi Valkeinen wrote: > > and not the clock used for the pixel clock? If so, I'm fine with having > > "fck" to be what it is currently, but then we need a new name for the > > clock used for pixel clock, which is consistent on all platforms. > > If there is a separate PRCM-provided clock used only for the pixel clock, > then that clock should have an alias name of "system_pixel_ck" or > something similar that is meaningful to the DSS driver. I think the > problem in this case is that "dss_dss_clk" is (optionally) used for two > purposes: optionally as a "main PRCM-provided functional clock" and > optionally as a system-provided pixel clock. Not only for pixel clock, but in the end it'll come out as pixel clock. I'm not sure what exactly is a "functional clock" here. I mean, one could think it as a basic functionality of DSS to read the pixels, manipulate them, and output them (with the rate of the pixel clock). However, I think there is one difference between the clock used just to enable the DSS registers, and the one used to output pixels: we need to be able to adjust the rate of the clock. Thus we need to have a common (omap2/3/4) clock name for it to be able to clk_get() it. Should that clock name be just the "main" clock provided automatically, or something else? Tomi