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=-17.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,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 E2265C4320A for ; Fri, 23 Jul 2021 19:28:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B8B0E60F22 for ; Fri, 23 Jul 2021 19:28:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229461AbhGWSrm (ORCPT ); Fri, 23 Jul 2021 14:47:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230490AbhGWSrm (ORCPT ); Fri, 23 Jul 2021 14:47:42 -0400 Received: from mail-ot1-x336.google.com (mail-ot1-x336.google.com [IPv6:2607:f8b0:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F727C061757 for ; Fri, 23 Jul 2021 12:28:14 -0700 (PDT) Received: by mail-ot1-x336.google.com with SMTP id c7-20020a9d27870000b02904d360fbc71bso3046839otb.10 for ; Fri, 23 Jul 2021 12:28:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:in-reply-to:references:from:user-agent:date:message-id :subject:to:cc; bh=Bs+9Wf2Rg7YUqulOFkE7bAQ3itXKARyReOSzJvhssws=; b=EZ92o+lU4+P+XV7xO6773WcUyvEJ/+NHJbWZkHjHBnYF8dDDdjb+oH7HgG/fmo4XEQ 8ZnGklqLIagB3CjPx52/0BFFaDy3J1PTTuLAi/AUmOx77rJR7GlZ2OxfBmx9+QKqLayf 44+/7xRfVvPMZMYJRm31me7qFPlWYWG/Np0ao= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from :user-agent:date:message-id:subject:to:cc; bh=Bs+9Wf2Rg7YUqulOFkE7bAQ3itXKARyReOSzJvhssws=; b=ABKS3zitSDEmSgrIqVNpMKd27S5+95AydGDBz4BMlPbZeWHO2tEE1EFLnsmnQwTUOl 4GHTyt9FEnLqbsKKCp/YaAlw/JQC3JGPdiyzmpHDZL9JZllhiRnFCrogYN3ND6w73Uvb 2D22Xjj2Uxc0CbXih269o5Nor3ZJSb6dhG/+WLkeU5wSo6YYaVPn8W+DJtSfftPnaGB0 swku7CzYWHiv+F3qlb6uBseQgLdgzxa8HY7BQ/+G4zxA6qevjit3BHs0zE1trNfTbERq rS4wQDuSWlEMAWhELtocWIIvgmBDM01JwHvVOSip1f1/8qeIkLWNQBcZmuGxh8+FcCHN fQcg== X-Gm-Message-State: AOAM5339ixRBag2ixuxXCBQpkLfZrjNgCBGOmQE8cDnweFcc7Ykd382v 0s+Lqanquq+75DYEzhwEATpJoTxtiInUwmPkepADkw== X-Google-Smtp-Source: ABdhPJz6hKhnuc07sMCNisJAktb5x8bleD4y8wHakw0tll6AwU3RSHxxohogKWMuvWqjWon3uBzCV+xu7sZ4SrYCDkM= X-Received: by 2002:a9d:8c7:: with SMTP id 65mr4160483otf.25.1627068493821; Fri, 23 Jul 2021 12:28:13 -0700 (PDT) Received: from 753933720722 named unknown by gmailapi.google.com with HTTPREST; Fri, 23 Jul 2021 19:28:13 +0000 MIME-Version: 1.0 In-Reply-To: References: <1623237532-20829-1-git-send-email-sibis@codeaurora.org> <1623237532-20829-2-git-send-email-sibis@codeaurora.org> From: Stephen Boyd User-Agent: alot/0.9.1 Date: Fri, 23 Jul 2021 19:28:13 +0000 Message-ID: Subject: Re: [PATCH v4 1/2] soc: qcom: aoss: Expose send for generic usecase To: Deepak Kumar Singh , Sibi Sankar , bjorn.andersson@linaro.org Cc: agross@kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, manivannan.sadhasivam@linaro.org, Chris Lew Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Quoting Deepak Kumar Singh (2021-07-23 02:51:50) > > On 7/21/2021 12:07 PM, Stephen Boyd wrote: > > Quoting Sibi Sankar (2021-06-09 04:18:51) > >> From: Deepak Kumar Singh > >> > >> Not all upcoming usecases will have an interface to allow the aoss > >> driver to hook onto. Expose the send api and create a get function to > >> enable drivers to send their own messages to aoss. > >> > >> Signed-off-by: Chris Lew > >> Signed-off-by: Deepak Kumar Singh > >> Reviewed-by: Bjorn Andersson > >> Signed-off-by: Sibi Sankar > >> --- > >> > >> v4: > >> * Fix compilation error due to missing qmp_put > >> * Minor typos [s/tarcks/tracks] > >> > >> drivers/soc/qcom/qcom_aoss.c | 70 ++++++++++++++++++++++++++++++++++++-- > >> include/linux/soc/qcom/qcom_aoss.h | 36 ++++++++++++++++++++ > >> 2 files changed, 104 insertions(+), 2 deletions(-) > >> create mode 100644 include/linux/soc/qcom/qcom_aoss.h > >> > >> diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c > >> index 934fcc4d2b05..e8f48760bac8 100644 > >> --- a/drivers/soc/qcom/qcom_aoss.c > >> +++ b/drivers/soc/qcom/qcom_aoss.c > >> @@ -522,13 +582,14 @@ static int qmp_probe(struct platform_device *pdev) > >> int irq; > >> int ret; > >> > >> - qmp = devm_kzalloc(&pdev->dev, sizeof(*qmp), GFP_KERNEL); > >> + qmp = kzalloc(sizeof(*qmp), GFP_KERNEL); > >> if (!qmp) > >> return -ENOMEM; > >> > >> qmp->dev = &pdev->dev; > >> init_waitqueue_head(&qmp->event); > >> mutex_init(&qmp->tx_lock); > >> + kref_init(&qmp->refcount); > >> > >> res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > >> qmp->msgram = devm_ioremap_resource(&pdev->dev, res); > >> @@ -569,6 +630,8 @@ static int qmp_probe(struct platform_device *pdev) > >> > >> platform_set_drvdata(pdev, qmp); > >> > >> + atomic_set(&qmp->orphan, 0); > >> + > >> return 0; > >> > >> err_remove_qdss_clk: > >> @@ -577,6 +640,7 @@ static int qmp_probe(struct platform_device *pdev) > >> qmp_close(qmp); > >> err_free_mbox: > >> mbox_free_channel(qmp->mbox_chan); > >> + kfree(qmp); > >> > >> return ret; > >> } > >> @@ -590,7 +654,9 @@ static int qmp_remove(struct platform_device *pdev) > >> qmp_cooling_devices_remove(qmp); > >> > >> qmp_close(qmp); > >> + atomic_set(&qmp->orphan, 1); > > This looks odd. Why are we letting the device be removed while it is in > > use by other drivers? Can't we pin the device with get_device() so it > > can't be removed and then prevent the driver from being removed until > > all the consumer drivers drop the reference, i.e. suppress sysfs unbind? > > > > Otherwise it looks like a generic problem that all provider devices, > > clks, regulators, gpios, etc. have to deal with and thus this > > hand-rolled mechanism can't be right. > > As per my earlier discussion with Bjorn, device could be unbound using > sysfs, in which case > > remove() is called irrespective of whether any client driver is holding > struct device reference > > or not. That's why i have added separate refcount for qmp handle and > marking it invalid if > > qmp_remove() is called. > We have struct device_driver::suppress_bind_attrs for that. Can you set it?