From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaud Pouliquen Subject: Re: [PATCH 09/18] ASoC: sti: Update DT example to match the driver code Date: Wed, 4 May 2016 09:52:19 +0200 Message-ID: <5729AA33.6020305@st.com> References: <1461236675-10176-1-git-send-email-peter.griffin@linaro.org> <6161197.8XCk69TI60@wuerfel> <20160426111532.GA5457@griffinp-ThinkPad-X1-Carbon-2nd> <5608365.uloflbeuqO@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <5608365.uloflbeuqO@wuerfel> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann , Peter Griffin Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, srinivas.kandagatla-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, maxime.coquelin-qxv4g6HH51o@public.gmane.org, patrice.chotard-qxv4g6HH51o@public.gmane.org, vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, ludovic.barre-qxv4g6HH51o@public.gmane.org List-Id: devicetree@vger.kernel.org hello Arnd, peter, On 04/26/2016 01:44 PM, Arnd Bergmann wrote: > On Tuesday 26 April 2016 12:15:32 Peter Griffin wrote: >>> >>>> If not what would you recommend instead? >>> >>> It's still not clear to me what that bit in the syscfg register >>> is for. Given the error message about "sti-audio-clk-glue", >>> I suspect that this is actually a clock controller and that >>> it should be using the clock binding with a separate driver >>> instead of manipulating the regmap directly from the audio driver. >> >> Luckily I do have the datasheet for the audio-glue sysconf register. >> >> It says: - >> >> [11:8] PCM_CLK_SEL: Selects the frequency synthesizer clock or the external >> PCM clock for each channel. >> >> The driver only ever sets this to 1 which selects the frequency synthesizer >> clock. So the bitfield of the register which the driver is using (PCM_CLK_SEL) >> is a clock mux. > > Ok, that sounds like it could be either a really simple clock driver > with just a few lines, or integrated into an existing clock driver > if you already have one for this syscon node. > > Arnd > FYI, Name of this glue is related to the register name. But it does not concern only clock... This glue register is used to : - select clock source ( clock framework or external clock from GPIO) => one bit field per IP instance (player->clk_sel) - select uniperiph player IP instance for PCM out. (http://www.spinics.net/lists/alsa-devel/msg49034.html) Regards Arnaud -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html