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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 5D9D7C00144 for ; Thu, 19 Aug 2021 15:23:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 464146056C for ; Thu, 19 Aug 2021 15:23:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239983AbhHSPYY convert rfc822-to-8bit (ORCPT ); Thu, 19 Aug 2021 11:24:24 -0400 Received: from coyote.holtmann.net ([212.227.132.17]:59363 "EHLO mail.holtmann.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240159AbhHSPYR (ORCPT ); Thu, 19 Aug 2021 11:24:17 -0400 Received: from smtpclient.apple (p5b3d23f8.dip0.t-ipconnect.de [91.61.35.248]) by mail.holtmann.org (Postfix) with ESMTPSA id 04B76CED17; Thu, 19 Aug 2021 17:23:37 +0200 (CEST) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.120.0.1.13\)) Subject: Re: [RFC PATCH 00/15] create power sequencing subsystem From: Marcel Holtmann In-Reply-To: <20210817005507.1507580-1-dmitry.baryshkov@linaro.org> Date: Thu, 19 Aug 2021 17:23:36 +0200 Cc: Andy Gross , Bjorn Andersson , Ulf Hansson , Johan Hedberg , Luiz Augusto von Dentz , Kalle Valo , "David S. Miller" , Jakub Kicinski , Stanimir Varbanov , MSM , linux-mmc@vger.kernel.org, open list , "open list:BLUETOOTH SUBSYSTEM" , ath10k@lists.infradead.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org Content-Transfer-Encoding: 8BIT Message-Id: <1CA665D1-86F0-45A1-862D-17DAB3ABA974@holtmann.org> References: <20210817005507.1507580-1-dmitry.baryshkov@linaro.org> To: Dmitry Baryshkov X-Mailer: Apple Mail (2.3654.120.0.1.13) Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Hi Dmitry, > This is an RFC of the proposed power sequencer subsystem. This is a > generification of the MMC pwrseq code. The subsystem tries to abstract > the idea of complex power-up/power-down/reset of the devices. > > The primary set of devices that promted me to create this patchset is > the Qualcomm BT+WiFi family of chips. They reside on serial+platform > interfaces (older generations) or on serial+PCIe (newer generations). > They require a set of external voltage regulators to be powered on and > (some of them) have separate WiFi and Bluetooth enable GPIOs. > > This patchset being an RFC tries to demonstrate the approach, design and > usage of the pwrseq subsystem. Following issues are present in the RFC > at this moment but will be fixed later if the overall approach would be > viewed as acceptable: > > - No documentation > While the code tries to be self-documenting proper documentation > would be required. > > - Minimal device tree bindings changes > There are no proper updates for the DT bindings (thus neither Rob > Herring nor devicetree are included in the To/Cc lists). The dt > schema changes would be a part of v1. > > - Lack of proper PCIe integration > At this moment support for PCIe is hacked up to be able to test the > PCIe part of qca6390. Proper PCIe support would require automatically > powering up the devices before the scan basing on the proper device > structure in the device tree. > > ---------------------------------------------------------------- > Dmitry Baryshkov (15): > power: add power sequencer subsystem > pwrseq: port MMC's pwrseq drivers to new pwrseq subsystem > mmc: core: switch to new pwrseq subsystem > ath10k: add support for pwrseq sequencing > Bluetooth: hci_qca: merge qca_power into qca_serdev > Bluetooth: hci_qca: merge init paths > Bluetooth: hci_qca: merge qca_power_on with qca_regulators_init > Bluetooth: hci_qca: futher rework of power on/off handling > Bluetooth: hci_qca: add support for pwrseq any chance you can try to abandon patching hci_qca. The serdev support in hci_uart is rather hacking into old line discipline code and it is not aging well. It is really becoming a mess. I would say that the Qualcomm serial devices could use a separate standalone serdev driver. A while I send an RFC for a new serdev driver. https://www.spinics.net/lists/linux-bluetooth/msg74918.html There I had the idea that simple vendor specifics can be in that driver (like the Broadcom part I added there), but frankly the QCA specifics are a bit too specific and it should be a separate driver. However I think this would be a good starting point. In general a H:4 based Bluetooth driver is dead simple with the help of h4_recv.h helper we have in the kernel. The complicated part is the power management pieces or any vendor specific low-power protocol they are running on that serial line. And since you are touching this anyway, doing a driver from scratch might be lot simpler and cleaner. It would surely help all the new QCA device showing up in the future. Regards Marcel 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=-4.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 68614C4338F for ; Thu, 19 Aug 2021 15:24:00 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 36CCF610A3 for ; Thu, 19 Aug 2021 15:24:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 36CCF610A3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=holtmann.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:To:References:Message-Id:Cc:Date: In-Reply-To:From:Subject:Mime-Version:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=L5kM+Qgd1rEZC3ORGRtxNq7HElvmiCWrB5FwVmYWkz4=; b=boHCpnPK+MxSGs A/pyyp/gWli9aXl0QUc/oaVI/WeiC9hmQQ+Cq5a2CxkhEqTqkkYK+po3rgR6xb2f49F7dxRNvgjwL D/c2loKGJQgj/l52J9ZlijEzn6fWy1JIibE1SYUOyexBcHfpwFalmGFhbLXjMi5f847wHlLAYMwXb QxNN86kSoiaO4J/z7av9hzNao717gMN72mrX/4zKIDPmYD3LoKm8fJCHIG4cdkBj6iWZq1ZPCVEjU CosRQDW7cIwK9/GxGy2ZvyY6QzdqsgM9zP+AUHLo6J8oT4V7+3YkYld/oNwYCqNX+IlxswoOjQMC5 nSnx1OnDMRFKf7m9ud8Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mGjtS-008oHX-FB; Thu, 19 Aug 2021 15:23:46 +0000 Received: from coyote.holtmann.net ([212.227.132.17] helo=mail.holtmann.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mGjtM-008oGg-3C for ath10k@lists.infradead.org; Thu, 19 Aug 2021 15:23:44 +0000 Received: from smtpclient.apple (p5b3d23f8.dip0.t-ipconnect.de [91.61.35.248]) by mail.holtmann.org (Postfix) with ESMTPSA id 04B76CED17; Thu, 19 Aug 2021 17:23:37 +0200 (CEST) Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.120.0.1.13\)) Subject: Re: [RFC PATCH 00/15] create power sequencing subsystem From: Marcel Holtmann In-Reply-To: <20210817005507.1507580-1-dmitry.baryshkov@linaro.org> Date: Thu, 19 Aug 2021 17:23:36 +0200 Cc: Andy Gross , Bjorn Andersson , Ulf Hansson , Johan Hedberg , Luiz Augusto von Dentz , Kalle Valo , "David S. Miller" , Jakub Kicinski , Stanimir Varbanov , MSM , linux-mmc@vger.kernel.org, open list , "open list:BLUETOOTH SUBSYSTEM" , ath10k@lists.infradead.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org Message-Id: <1CA665D1-86F0-45A1-862D-17DAB3ABA974@holtmann.org> References: <20210817005507.1507580-1-dmitry.baryshkov@linaro.org> To: Dmitry Baryshkov X-Mailer: Apple Mail (2.3654.120.0.1.13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210819_082340_329024_1A8311D1 X-CRM114-Status: GOOD ( 27.67 ) X-BeenThere: ath10k@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "ath10k" Errors-To: ath10k-bounces+ath10k=archiver.kernel.org@lists.infradead.org Hi Dmitry, > This is an RFC of the proposed power sequencer subsystem. This is a > generification of the MMC pwrseq code. The subsystem tries to abstract > the idea of complex power-up/power-down/reset of the devices. > > The primary set of devices that promted me to create this patchset is > the Qualcomm BT+WiFi family of chips. They reside on serial+platform > interfaces (older generations) or on serial+PCIe (newer generations). > They require a set of external voltage regulators to be powered on and > (some of them) have separate WiFi and Bluetooth enable GPIOs. > > This patchset being an RFC tries to demonstrate the approach, design and > usage of the pwrseq subsystem. Following issues are present in the RFC > at this moment but will be fixed later if the overall approach would be > viewed as acceptable: > > - No documentation > While the code tries to be self-documenting proper documentation > would be required. > > - Minimal device tree bindings changes > There are no proper updates for the DT bindings (thus neither Rob > Herring nor devicetree are included in the To/Cc lists). The dt > schema changes would be a part of v1. > > - Lack of proper PCIe integration > At this moment support for PCIe is hacked up to be able to test the > PCIe part of qca6390. Proper PCIe support would require automatically > powering up the devices before the scan basing on the proper device > structure in the device tree. > > ---------------------------------------------------------------- > Dmitry Baryshkov (15): > power: add power sequencer subsystem > pwrseq: port MMC's pwrseq drivers to new pwrseq subsystem > mmc: core: switch to new pwrseq subsystem > ath10k: add support for pwrseq sequencing > Bluetooth: hci_qca: merge qca_power into qca_serdev > Bluetooth: hci_qca: merge init paths > Bluetooth: hci_qca: merge qca_power_on with qca_regulators_init > Bluetooth: hci_qca: futher rework of power on/off handling > Bluetooth: hci_qca: add support for pwrseq any chance you can try to abandon patching hci_qca. The serdev support in hci_uart is rather hacking into old line discipline code and it is not aging well. It is really becoming a mess. I would say that the Qualcomm serial devices could use a separate standalone serdev driver. A while I send an RFC for a new serdev driver. https://www.spinics.net/lists/linux-bluetooth/msg74918.html There I had the idea that simple vendor specifics can be in that driver (like the Broadcom part I added there), but frankly the QCA specifics are a bit too specific and it should be a separate driver. However I think this would be a good starting point. In general a H:4 based Bluetooth driver is dead simple with the help of h4_recv.h helper we have in the kernel. The complicated part is the power management pieces or any vendor specific low-power protocol they are running on that serial line. And since you are touching this anyway, doing a driver from scratch might be lot simpler and cleaner. It would surely help all the new QCA device showing up in the future. Regards Marcel _______________________________________________ ath10k mailing list ath10k@lists.infradead.org http://lists.infradead.org/mailman/listinfo/ath10k