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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98CA2C7618E for ; Fri, 21 Apr 2023 07:26:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230036AbjDUH0w (ORCPT ); Fri, 21 Apr 2023 03:26:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229712AbjDUH0w (ORCPT ); Fri, 21 Apr 2023 03:26:52 -0400 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46DA82680; Fri, 21 Apr 2023 00:26:49 -0700 (PDT) Received: (Authenticated sender: herve.codina@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 0A6C22000F; Fri, 21 Apr 2023 07:26:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1682062007; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rg7mAqWYm80zziSBLUX+QJbAH6dTgm61KDeO9JG0CbU=; b=WIxsnrcBlhc9LsM3u1yFOmR9oM19m7i3CMb6shmBvGggsaVHgJnCVF8YbOfNLJs4Drj7dI Gnk4+aexGNF6tVsushn80roLXBUgjed/c4CQRPqkNYNY1tz7emmr9KyuJGq1XaIg34OMoG CigzyYfobZpKMu//UHsn/R7MgA6hlwrtdLY6Ns2VfxK+kP8pN5N0a7knbl3aCDkMEy+afA BbmDPWjJ6u88w+4xtx+ztmKh/sx88ytClv9s4IiBhB6Y0NmiscKObKuQ8oyEfpr8nl0rUJ o7Wle9mu+0sEEs2FmyRmRPbD1rN14crmFQbc9rgRxn5dDIAhkzjkBk9o5SqfXQ== Date: Fri, 21 Apr 2023 09:26:45 +0200 From: Herve Codina To: Lee Jones , Krzysztof Kozlowski Cc: Rob Herring , Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, alsa-devel@alsa-project.org, Christophe Leroy , Thomas Petazzoni Subject: Re: [PATCH v6 3/7] mfd: Add support for the Lantiq PEF2256 framer Message-ID: <20230421092645.56127f11@bootlin.com> In-Reply-To: <20230420134703.GC996918@google.com> References: <20230417171601.74656-1-herve.codina@bootlin.com> <20230417171601.74656-4-herve.codina@bootlin.com> <20230420123946.GB996918@google.com> <20230420151551.78c1288b@bootlin.com> <20230420134703.GC996918@google.com> Organization: Bootlin X-Mailer: Claws Mail 4.1.1 (GTK 3.24.37; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Lee, Krzysztof, On Thu, 20 Apr 2023 14:47:03 +0100 Lee Jones wrote: > On Thu, 20 Apr 2023, Herve Codina wrote: > > > On Thu, 20 Apr 2023 13:39:46 +0100 > > Lee Jones wrote: > > > > > On Mon, 17 Apr 2023, Herve Codina wrote: > > > > > > > The Lantiq PEF2256 is a framer and line interface component designed to > > > > fulfill all required interfacing between an analog E1/T1/J1 line and the > > > > digital PCM system highway/H.100 bus. > > > > > > > > Signed-off-by: Herve Codina > > > > --- > > > > drivers/mfd/Kconfig | 16 + > > > > drivers/mfd/Makefile | 1 + > > > > drivers/mfd/pef2256-regs.h | 250 ++++++++++ > > > > drivers/mfd/pef2256.c | 950 ++++++++++++++++++++++++++++++++++++ > > > > > > 95% of this driver needs to be moved somewhere else. > > > > > > What is a Framer? Perhaps sound/ is a good candidate? > > > > The pef2256 framer is a device that transfers data to/from a TDM (time-slots > > data) from/to quite old telecommunication lines (E1 in my case). > > Several subsystem can set/get data to/from the TDM. Each device using their > > own time-slots set. > > > > On my use-case, I have some audio consumer and a not yet upstreamed HDLC > > consumer. Both of them uses the framer to know the E1 link state. > > The framer needs to be initialized 'globally' and not by a specific consumer > > as several consumers can use the framer. > > I can't think of a good place for this. > > If all else fails, it's drivers/misc > > > > > include/linux/mfd/pef2256.h | 52 ++ > > > > 5 files changed, 1269 insertions(+) > > > > create mode 100644 drivers/mfd/pef2256-regs.h > > > > create mode 100644 drivers/mfd/pef2256.c > > > > create mode 100644 include/linux/mfd/pef2256.h > > > > > > [...] > > > > > > > +static int pef2256_add_audio_devices(struct pef2256 *pef2256) > > > > +{ > > > > + const char *compatible = "lantiq,pef2256-codec"; > > > > + struct mfd_cell *audio_devs; > > > > + struct device_node *np; > > > > + unsigned int count = 0; > > > > + unsigned int i; > > > > + int ret; > > > > + > > > > + for_each_available_child_of_node(pef2256->dev->of_node, np) { > > > > + if (of_device_is_compatible(np, compatible)) > > > > + count++; > > > > + } > > > > > > Converting Device Tree nodes into MFD cells to register with the > > > Platform Device API is not a reasonable use-case of MFD. > > > > > > Have the CODEC driver match on "lantiq,pef2256-codec" and let it > > > instantiate itself. > > > > As the framer is going to used by several subsystem, I cannot instantiate > > it in the specific ASoC subsystem. > > > > > > > > Your first version using of_platform_populate() was closer to the mark. > > > > The issue was that I need MFD cells for the pinctrl part. > > Why can't it be represented in DT? The pinctrl part has no specific compatible string. Not sure that a compatible string for pinctrl can be accepted as there is only one pinctrl subnode and no specific reg for this subnode. The DT looks like this: framer@2000000 { compatible = "lantiq,pef2256"; reg = <0x2000000 0x100>; ... pinctrl { pef2256_rpa_sypr: rpa-pins { pins = "RPA"; function = "SYPR"; }; }; pef2256_codec0: codec-0 { compatible = "lantiq,pef2256-codec"; #sound-dai-cells = <0>; sound-name-prefix = "PEF2256_0"; }; }; Krzysztof, is it acceptable to have a compatible string in the pinctrl node ? In this case, it will looks like this: framer@2000000 { compatible = "lantiq,pef2256"; reg = <0x2000000 0x100>; ... pinctrl { compatible = "lantiq,pef2256-pinctrl"; pef2256_rpa_sypr: rpa-pins { pins = "RPA"; function = "SYPR"; }; }; pef2256_codec0: codec-0 { compatible = "lantiq,pef2256-codec"; #sound-dai-cells = <0>; sound-name-prefix = "PEF2256_0"; }; }; Best regards, Hervé