From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0F49C433E6 for ; Wed, 10 Mar 2021 13:34:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 74EBA64FD6 for ; Wed, 10 Mar 2021 13:34:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233433AbhCJNdj (ORCPT ); Wed, 10 Mar 2021 08:33:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47968 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232931AbhCJNdZ (ORCPT ); Wed, 10 Mar 2021 08:33:25 -0500 Received: from mail-qk1-x72c.google.com (mail-qk1-x72c.google.com [IPv6:2607:f8b0:4864:20::72c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E152C061760; Wed, 10 Mar 2021 05:33:23 -0800 (PST) Received: by mail-qk1-x72c.google.com with SMTP id f124so16727385qkj.5; Wed, 10 Mar 2021 05:33:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=xATgDCcvjbRfKhf77xL4HQKVKsZXwxoQX6S2FdKT3Oo=; b=bl9foFVuWm1U0ekqf1RlZ6JOgyHSxk20HsshPAc/WzmNMQkpqow9aJHwikbBuhzGt5 jT1S7UCkiQhavHDTqfeS/7Pfr5/IePsLcFDW+xtC3oZT8urNRddeoTEDdbA1IepPMPk+ opy2by+nNj9L9mcjh3ek7aNkXjf9fKBBKm2Jqgd5tMFigjlDZjBf2JhaP0RIxWNQxb2T /+3P/012KMPMRD/pd+hAGnOJoVnTUWu55a3JQpQ9tb6n/wtLR9H0ZJW4J2/1/FeMOnPA ckGsAVCt8a/1taU7nsP+U4gCNpvnevNcHi/hhmmnz1IViwSN4ngtMzFuAOU/mXVgcYBY nErg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=xATgDCcvjbRfKhf77xL4HQKVKsZXwxoQX6S2FdKT3Oo=; b=ZNjDI9cRf+sLSltR3BDW02f7FXgiWXtMRWkaeb/iDEeBs7AdZlmaRmUlEpmMnjaA3/ sW8xBJw8i4/KHMnlC5+Jd5MDJjgehmHG5FAdeGdra8RTlMEz01zTHbqwbYnI3kTwZHXM kifVoocHori5qzZgF42UBf3rjhyI2hptmEpG26VdkFJLN9MhBL9YExC9+7jFC1Fgcn/q 9ciMZlG70CpIV2vAsmUkIgN661endpnSXJYh4J5u2WXnAViE3X9zn9lFOrAB9b87DnaA Xj881ReCcwihRX/4FT4xcd5cMkmbY7D0Ftwxr66/OB/Pftqk6l6FXS6CNoVcCdcEtCoJ 2c7w== X-Gm-Message-State: AOAM530UEX3kv7pdwyDm4SL1sycoEV3eCStRINADWWo+goaWjdmFouz9 EpwgpCxKQrrQADTXw6x0ZbqjwwR4MoFCI+hGkZc= X-Google-Smtp-Source: ABdhPJwsnjO9VMCLT+e6qoznWlE6iGQjtNS8w36gj0aKWvcdVWBIbKTu/A3JNEQWuep1O/iNA0xg755nBa0vz1K9AyA= X-Received: by 2002:a05:620a:89d:: with SMTP id b29mr2468495qka.103.1615383202487; Wed, 10 Mar 2021 05:33:22 -0800 (PST) MIME-Version: 1.0 References: <1615209750-2357-1-git-send-email-shengjiu.wang@nxp.com> <1615209750-2357-4-git-send-email-shengjiu.wang@nxp.com> <20210310024834.GA1623179@robh.at.kernel.org> In-Reply-To: <20210310024834.GA1623179@robh.at.kernel.org> From: Shengjiu Wang Date: Wed, 10 Mar 2021 21:33:11 +0800 Message-ID: Subject: Re: [PATCH v4 3/6] ASoC: dt-bindings: fsl_rpmsg: Add binding doc for rpmsg cpu dai driver To: Rob Herring Cc: Shengjiu Wang , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , alsa-devel@alsa-project.org, Timur Tabi , Liam Girdwood , linuxppc-dev , Xiubo Li , linux-kernel , Takashi Iwai , Nicolin Chen , Mark Brown , Fabio Estevam Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Rob On Wed, Mar 10, 2021 at 10:49 AM Rob Herring wrote: > > On Mon, Mar 08, 2021 at 09:22:27PM +0800, Shengjiu Wang wrote: > > fsl_rpmsg cpu dai driver is driver for rpmsg audio, which is mainly used > > Bindings describe h/w blocks, not drivers. I will modify the descriptions. but here it is a virtual device. the mapping in real h/w is cortex M core, Cortex M core controls the SAI, DMA interface. What we see from Linux side is a audio service through rpmsg channel. > > > for getting the user's configuration from device tree and configure the > > clocks which is used by Cortex-M core. So in this document define the > > needed property. > > > > Signed-off-by: Shengjiu Wang > > --- > > .../devicetree/bindings/sound/fsl,rpmsg.yaml | 118 ++++++++++++++++++ > > 1 file changed, 118 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml > > > > diff --git a/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml > > new file mode 100644 > > index 000000000000..5731c1fbc0a6 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml > > @@ -0,0 +1,118 @@ > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/sound/fsl,rpmsg.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: NXP Audio RPMSG CPU DAI Controller > > + > > +maintainers: > > + - Shengjiu Wang > > + > > +description: | > > + fsl_rpmsg cpu dai driver is virtual driver for rpmsg audio, which doesn't > > + touch hardware. It is mainly used for getting the user's configuration > > + from device tree and configure the clocks which is used by Cortex-M core. > > + So in this document define the needed property. > > + > > +properties: > > + compatible: > > + enum: > > + - fsl,imx7ulp-rpmsg > > + - fsl,imx8mn-rpmsg > > + - fsl,imx8mm-rpmsg > > + - fsl,imx8mp-rpmsg > > + > > + model: > > + $ref: /schemas/types.yaml#/definitions/string > > + description: User specified audio sound card name > > + > > + clocks: > > + items: > > + - description: Peripheral clock for register access > > + - description: Master clock > > + - description: DMA clock for DMA register access > > + - description: Parent clock for multiple of 8kHz sample rates > > + - description: Parent clock for multiple of 11kHz sample rates > > + minItems: 5 > > If this doesn't touch hardware, what are these clocks for? When the cortex-M core support audio service, these clock needed prepared & enabled by ALSA driver. > > You don't need 'minItems' unless it's less than the number of 'items'. Ok, I will remove this minItems. > > > + > > + clock-names: > > + items: > > + - const: ipg > > + - const: mclk > > + - const: dma > > + - const: pll8k > > + - const: pll11k > > + minItems: 5 > > + > > + power-domains: > > + maxItems: 1 > > + > > + fsl,audioindex: > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [0, 1] > > + default: 0 > > + description: Instance index for sound card in > > + M core side, which share one rpmsg > > + channel. > > We don't do indexes in DT. What's this numbering tied to? I will remove it. it is not necessary > > > + > > + fsl,version: > > version of what? > > This seems odd at best. > I will remove it. it is not necessary > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [1, 2] > > You're going to update this with every new firmware version? > > > + default: 2 > > + description: The version of M core image, which is > > + to make driver compatible with different image. > > + > > + fsl,buffer-size: > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + description: pre allocate dma buffer size > > How can you have DMA, this doesn't touch h/w? The DMA is handled by M core image for sound playback and capture. we need to allocated buffer in Linux side. here just make the buffer size to be configurable. > > > + > > + fsl,enable-lpa: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: enable low power audio path. > > + > > + fsl,rpmsg-out: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: | > > + This is a boolean property. If present, the transmitting function > > + will be enabled. > > + > > + fsl,rpmsg-in: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: | > > + This is a boolean property. If present, the receiving function > > + will be enabled. > > + > > + fsl,codec-type: > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [0, 1, 2] > > + default: 0 > > + description: Sometimes the codec is registered by > > + driver not by the device tree, this items > > + can be used to distinguish codecs. > > How does one decide what value to use? I will add more description: 0: dummy codec 1: WM8960 codec 2: AK4497 codec > > > + > > + audio-codec: > > + $ref: /schemas/types.yaml#/definitions/phandle > > + description: The phandle of the audio codec > > The codec is controlled from the Linux side? yes. > > > + > > + memory-region: > > + $ref: /schemas/types.yaml#/definitions/phandle > > + description: phandle to the reserved memory nodes > > + > > +required: > > + - compatible > > + - fsl,audioindex > > + - fsl,version > > + - fsl,buffer-size > > + > > +additionalProperties: false > > + > > +examples: > > + - | > > + rpmsg_audio: rpmsg_audio { > > + compatible = "fsl,imx8mn-rpmsg"; > > + fsl,audioindex = <0> ; > > + fsl,version = <2>; > > + fsl,buffer-size = <0x6000000>; > > + fsl,enable-lpa; > > How does this work? Don't you need somewhere to put the 'rpmsg' data? The rpmsg data is not handled in this "rpmsg_audio" device, it is just to prepare the resource for rpmsg audio function, the clock, the memory the power... The rpmsg data is handled in imx-pcm-rpmsg.c and imx-audio-rpmsg.c These devices is registered by imx remoteproc driver. I will update this document in v5 Best regards Wang Shengjiu From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.7 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B51AC433E6 for ; Wed, 10 Mar 2021 13:35:31 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 41E8064FE8 for ; Wed, 10 Mar 2021 13:35:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 41E8064FE8 Authentication-Results: mail.kernel.org; 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charset="UTF-8" Cc: "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , alsa-devel@alsa-project.org, Timur Tabi , Xiubo Li , Fabio Estevam , Shengjiu Wang , Takashi Iwai , Liam Girdwood , linux-kernel , Nicolin Chen , Mark Brown , linuxppc-dev X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" Hi Rob On Wed, Mar 10, 2021 at 10:49 AM Rob Herring wrote: > > On Mon, Mar 08, 2021 at 09:22:27PM +0800, Shengjiu Wang wrote: > > fsl_rpmsg cpu dai driver is driver for rpmsg audio, which is mainly used > > Bindings describe h/w blocks, not drivers. I will modify the descriptions. but here it is a virtual device. the mapping in real h/w is cortex M core, Cortex M core controls the SAI, DMA interface. What we see from Linux side is a audio service through rpmsg channel. > > > for getting the user's configuration from device tree and configure the > > clocks which is used by Cortex-M core. So in this document define the > > needed property. > > > > Signed-off-by: Shengjiu Wang > > --- > > .../devicetree/bindings/sound/fsl,rpmsg.yaml | 118 ++++++++++++++++++ > > 1 file changed, 118 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml > > > > diff --git a/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml > > new file mode 100644 > > index 000000000000..5731c1fbc0a6 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml > > @@ -0,0 +1,118 @@ > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/sound/fsl,rpmsg.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: NXP Audio RPMSG CPU DAI Controller > > + > > +maintainers: > > + - Shengjiu Wang > > + > > +description: | > > + fsl_rpmsg cpu dai driver is virtual driver for rpmsg audio, which doesn't > > + touch hardware. It is mainly used for getting the user's configuration > > + from device tree and configure the clocks which is used by Cortex-M core. > > + So in this document define the needed property. > > + > > +properties: > > + compatible: > > + enum: > > + - fsl,imx7ulp-rpmsg > > + - fsl,imx8mn-rpmsg > > + - fsl,imx8mm-rpmsg > > + - fsl,imx8mp-rpmsg > > + > > + model: > > + $ref: /schemas/types.yaml#/definitions/string > > + description: User specified audio sound card name > > + > > + clocks: > > + items: > > + - description: Peripheral clock for register access > > + - description: Master clock > > + - description: DMA clock for DMA register access > > + - description: Parent clock for multiple of 8kHz sample rates > > + - description: Parent clock for multiple of 11kHz sample rates > > + minItems: 5 > > If this doesn't touch hardware, what are these clocks for? When the cortex-M core support audio service, these clock needed prepared & enabled by ALSA driver. > > You don't need 'minItems' unless it's less than the number of 'items'. Ok, I will remove this minItems. > > > + > > + clock-names: > > + items: > > + - const: ipg > > + - const: mclk > > + - const: dma > > + - const: pll8k > > + - const: pll11k > > + minItems: 5 > > + > > + power-domains: > > + maxItems: 1 > > + > > + fsl,audioindex: > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [0, 1] > > + default: 0 > > + description: Instance index for sound card in > > + M core side, which share one rpmsg > > + channel. > > We don't do indexes in DT. What's this numbering tied to? I will remove it. it is not necessary > > > + > > + fsl,version: > > version of what? > > This seems odd at best. > I will remove it. it is not necessary > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [1, 2] > > You're going to update this with every new firmware version? > > > + default: 2 > > + description: The version of M core image, which is > > + to make driver compatible with different image. > > + > > + fsl,buffer-size: > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + description: pre allocate dma buffer size > > How can you have DMA, this doesn't touch h/w? The DMA is handled by M core image for sound playback and capture. we need to allocated buffer in Linux side. here just make the buffer size to be configurable. > > > + > > + fsl,enable-lpa: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: enable low power audio path. > > + > > + fsl,rpmsg-out: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: | > > + This is a boolean property. If present, the transmitting function > > + will be enabled. > > + > > + fsl,rpmsg-in: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: | > > + This is a boolean property. If present, the receiving function > > + will be enabled. > > + > > + fsl,codec-type: > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [0, 1, 2] > > + default: 0 > > + description: Sometimes the codec is registered by > > + driver not by the device tree, this items > > + can be used to distinguish codecs. > > How does one decide what value to use? I will add more description: 0: dummy codec 1: WM8960 codec 2: AK4497 codec > > > + > > + audio-codec: > > + $ref: /schemas/types.yaml#/definitions/phandle > > + description: The phandle of the audio codec > > The codec is controlled from the Linux side? yes. > > > + > > + memory-region: > > + $ref: /schemas/types.yaml#/definitions/phandle > > + description: phandle to the reserved memory nodes > > + > > +required: > > + - compatible > > + - fsl,audioindex > > + - fsl,version > > + - fsl,buffer-size > > + > > +additionalProperties: false > > + > > +examples: > > + - | > > + rpmsg_audio: rpmsg_audio { > > + compatible = "fsl,imx8mn-rpmsg"; > > + fsl,audioindex = <0> ; > > + fsl,version = <2>; > > + fsl,buffer-size = <0x6000000>; > > + fsl,enable-lpa; > > How does this work? Don't you need somewhere to put the 'rpmsg' data? The rpmsg data is not handled in this "rpmsg_audio" device, it is just to prepare the resource for rpmsg audio function, the clock, the memory the power... The rpmsg data is handled in imx-pcm-rpmsg.c and imx-audio-rpmsg.c These devices is registered by imx remoteproc driver. I will update this document in v5 Best regards Wang Shengjiu