From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Zapolskiy Subject: Re: [PATCH 4/7] mfd: ds90ux9xx: add TI DS90Ux9xx de-/serializer MFD driver Date: Fri, 12 Oct 2018 10:41:20 +0300 Message-ID: <63733d2e-f95e-8894-f2b0-0b551b5cfeeb@mentor.com> References: <20181008211205.2900-1-vz@mleia.com> <20181008211205.2900-5-vz@mleia.com> <20181012060314.GU4939@dell> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181012060314.GU4939@dell> Sender: linux-kernel-owner@vger.kernel.org To: Lee Jones , Laurent Pinchart Cc: Vladimir Zapolskiy , Linus Walleij , Rob Herring , Marek Vasut , Wolfram Sang , devicetree@vger.kernel.org, linux-gpio@vger.kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-gpio@vger.kernel.org Hi Lee, On 10/12/2018 09:03 AM, Lee Jones wrote: > On Tue, 09 Oct 2018, Vladimir Zapolskiy wrote: > >> From: Vladimir Zapolskiy >> >> The change adds I2C device driver for TI DS90Ux9xx de-/serializers, >> support of subdevice controllers is done in separate drivers, because >> not all IC functionality may be needed in particular situations, and >> this can be fine grained controlled in device tree. >> >> The development of the driver was a collaborative work, the >> contribution done by Balasubramani Vivekanandan includes: >> * original implementation of the driver based on a reference driver, >> * regmap powered interrupt controller support on serializers, >> * support of implicitly or improperly specified in device tree ICs, >> * support of device properties and attributes: backward compatible >> mode, low frequency operation mode, spread spectrum clock generator. >> >> Contribution by Steve Longerbeam: >> * added ds90ux9xx_read_indirect() function, >> * moved number of links property and added ds90ux9xx_num_fpd_links(), >> * moved and updated ds90ux9xx_get_link_status() function to core driver, >> * added fpd_link_show device attribute. >> >> Sandeep Jain added support of pixel clock edge configuration. >> >> Signed-off-by: Vladimir Zapolskiy >> --- >> drivers/mfd/Kconfig | 14 + >> drivers/mfd/Makefile | 1 + >> drivers/mfd/ds90ux9xx-core.c | 879 ++++++++++++++++++++++++++++++++++ >> include/linux/mfd/ds90ux9xx.h | 42 ++ >> 4 files changed, 936 insertions(+) >> create mode 100644 drivers/mfd/ds90ux9xx-core.c >> create mode 100644 include/linux/mfd/ds90ux9xx.h >> >> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig >> index 8c5dfdce4326..a969fa123f64 100644 >> --- a/drivers/mfd/Kconfig >> +++ b/drivers/mfd/Kconfig >> @@ -1280,6 +1280,20 @@ config MFD_DM355EVM_MSP >> boards. MSP430 firmware manages resets and power sequencing, >> inputs from buttons and the IR remote, LEDs, an RTC, and more. >> >> +config MFD_DS90UX9XX >> + tristate "TI DS90Ux9xx FPD-Link de-/serializer driver" >> + depends on I2C && OF >> + select MFD_CORE >> + select REGMAP_I2C >> + help >> + Say yes here to enable support for TI DS90UX9XX de-/serializer ICs. >> + >> + This driver provides basic support for setting up the de-/serializer >> + chips. Additional functionalities like connection handling to >> + remote de-/serializers, I2C bridging, pin multiplexing, GPIO >> + controller and so on are provided by separate drivers and should >> + enabled individually. > > This is not an MFD driver. Why do you think so? The representation of the ICs into device tree format of hardware description shows that this is a truly MFD driver with multiple IP subcomponents naturally mapped into MFD cells. Basically it is possible to replace explicit of_platform_populate() by adding a "simple-mfd" compatible, if it is desired. > After a 30 second Google of what this device actually does, perhaps > drivers/media might be a better fit? > I assume it would be quite unusual to add a driver with NO media functions and controls into drivers/media. Laurent, can you please share your opinion? -- Best wishes, Vladimir 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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 0A3A6C43441 for ; Fri, 12 Oct 2018 07:41:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB6F82087D for ; Fri, 12 Oct 2018 07:41:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BB6F82087D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mentor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727565AbeJLPMm (ORCPT ); Fri, 12 Oct 2018 11:12:42 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:35792 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726761AbeJLPMl (ORCPT ); Fri, 12 Oct 2018 11:12:41 -0400 Received: from nat-ies.mentorg.com ([192.94.31.2] helo=SVR-IES-MBX-04.mgc.mentorg.com) by relay1.mentorg.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-SHA384:256) id 1gAs4c-0002SC-3w from Vladimir_Zapolskiy@mentor.com ; Fri, 12 Oct 2018 00:41:26 -0700 Received: from [137.202.108.125] (137.202.0.90) by SVR-IES-MBX-04.mgc.mentorg.com (139.181.222.4) with Microsoft SMTP Server (TLS) id 15.0.1320.4; Fri, 12 Oct 2018 08:41:21 +0100 Subject: Re: [PATCH 4/7] mfd: ds90ux9xx: add TI DS90Ux9xx de-/serializer MFD driver To: Lee Jones , Laurent Pinchart References: <20181008211205.2900-1-vz@mleia.com> <20181008211205.2900-5-vz@mleia.com> <20181012060314.GU4939@dell> CC: Vladimir Zapolskiy , Linus Walleij , Rob Herring , Marek Vasut , Wolfram Sang , , , , From: Vladimir Zapolskiy Message-ID: <63733d2e-f95e-8894-f2b0-0b551b5cfeeb@mentor.com> Date: Fri, 12 Oct 2018 10:41:20 +0300 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:45.0) Gecko/20100101 Icedove/45.2.0 MIME-Version: 1.0 In-Reply-To: <20181012060314.GU4939@dell> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [137.202.0.90] X-ClientProxiedBy: SVR-IES-MBX-03.mgc.mentorg.com (139.181.222.3) To SVR-IES-MBX-04.mgc.mentorg.com (139.181.222.4) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Lee, On 10/12/2018 09:03 AM, Lee Jones wrote: > On Tue, 09 Oct 2018, Vladimir Zapolskiy wrote: > >> From: Vladimir Zapolskiy >> >> The change adds I2C device driver for TI DS90Ux9xx de-/serializers, >> support of subdevice controllers is done in separate drivers, because >> not all IC functionality may be needed in particular situations, and >> this can be fine grained controlled in device tree. >> >> The development of the driver was a collaborative work, the >> contribution done by Balasubramani Vivekanandan includes: >> * original implementation of the driver based on a reference driver, >> * regmap powered interrupt controller support on serializers, >> * support of implicitly or improperly specified in device tree ICs, >> * support of device properties and attributes: backward compatible >> mode, low frequency operation mode, spread spectrum clock generator. >> >> Contribution by Steve Longerbeam: >> * added ds90ux9xx_read_indirect() function, >> * moved number of links property and added ds90ux9xx_num_fpd_links(), >> * moved and updated ds90ux9xx_get_link_status() function to core driver, >> * added fpd_link_show device attribute. >> >> Sandeep Jain added support of pixel clock edge configuration. >> >> Signed-off-by: Vladimir Zapolskiy >> --- >> drivers/mfd/Kconfig | 14 + >> drivers/mfd/Makefile | 1 + >> drivers/mfd/ds90ux9xx-core.c | 879 ++++++++++++++++++++++++++++++++++ >> include/linux/mfd/ds90ux9xx.h | 42 ++ >> 4 files changed, 936 insertions(+) >> create mode 100644 drivers/mfd/ds90ux9xx-core.c >> create mode 100644 include/linux/mfd/ds90ux9xx.h >> >> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig >> index 8c5dfdce4326..a969fa123f64 100644 >> --- a/drivers/mfd/Kconfig >> +++ b/drivers/mfd/Kconfig >> @@ -1280,6 +1280,20 @@ config MFD_DM355EVM_MSP >> boards. MSP430 firmware manages resets and power sequencing, >> inputs from buttons and the IR remote, LEDs, an RTC, and more. >> >> +config MFD_DS90UX9XX >> + tristate "TI DS90Ux9xx FPD-Link de-/serializer driver" >> + depends on I2C && OF >> + select MFD_CORE >> + select REGMAP_I2C >> + help >> + Say yes here to enable support for TI DS90UX9XX de-/serializer ICs. >> + >> + This driver provides basic support for setting up the de-/serializer >> + chips. Additional functionalities like connection handling to >> + remote de-/serializers, I2C bridging, pin multiplexing, GPIO >> + controller and so on are provided by separate drivers and should >> + enabled individually. > > This is not an MFD driver. Why do you think so? The representation of the ICs into device tree format of hardware description shows that this is a truly MFD driver with multiple IP subcomponents naturally mapped into MFD cells. Basically it is possible to replace explicit of_platform_populate() by adding a "simple-mfd" compatible, if it is desired. > After a 30 second Google of what this device actually does, perhaps > drivers/media might be a better fit? > I assume it would be quite unusual to add a driver with NO media functions and controls into drivers/media. Laurent, can you please share your opinion? -- Best wishes, Vladimir