From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x227OjIJ15ffp3xNKXc1Wavfa3+vjNMwUAh1wd0KG36Lfok0XBFazPnst9iYpgght8uOMCmBo ARC-Seal: i=1; a=rsa-sha256; t=1517475199; cv=none; d=google.com; s=arc-20160816; b=dohkDfFGpfwd0qRLeDNqt59XyhNhshn87/zOmTFDQfzro+z8Mh7+vpDDWEETLzn6gQ Pnj4SqM0eMLNvUotTP/Bra13R74IKScbVFT2pLxeDJ0I/qqhLlnU5ocWgMPL/RmKCHC5 3tk3/mGu3hii6VvkQdG9gKZC9PrF0M65vUbvTQbxkVUMlxP75cj15QXiP4IanviXHIrw K9GUQ6/k2tgS5dgrRFo4VWzsW8S488yNFHz/gGtoCQ1abDRnepMA0J/IJb3bWYVwcdFM TRz1j8v/GIMrEkgLUjR2b6JaO5jb08RareHEVQlY0JKkkP38Y6zaE+2AnDg8Q+X26f+z mxLA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-language:content-transfer-encoding:in-reply-to:mime-version :user-agent:date:message-id:from:references:cc:to:subject :dmarc-filter:dkim-signature:dkim-signature :arc-authentication-results; bh=iaWcD20VeB9+z9GkNE4KnN4POpMPP5I8ZV9DGziguVQ=; b=KJxgSoBLluf3nSTnwK829qcbYie2zLM33Qx1QFfSBsE7YhqI/5iwWBzTe4bunltAlm g9j8+Tcm+EGhrU4515FR/6HID1JWl8xkY0UVmzVixc/gDHiUnhb2pBjukQQBxM3umviH djNo0tegInJrLOtGh81b/NCriJUgVGhHi1lFXYi8RA0T6EfnNC2pRV35581Hzsea+JVx LLf4wvErTSfxI6HQqpbezvb6hkUsD6EQ/3jbzHhRcFx1rm+PfnTYw8lSpHNmP67HAMNI gPl128p4v/8WaBIs39hiwwI2GX7EYrn1P9f7ewB9gnBD89kYYuGffH78DQGCJmvq2l2R 27GQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@codeaurora.org header.s=default header.b=FbTbFLra; dkim=pass header.i=@codeaurora.org header.s=default header.b=Vk0CYrdz; spf=pass (google.com: domain of vivek.gautam@codeaurora.org designates 198.145.29.96 as permitted sender) smtp.mailfrom=vivek.gautam@codeaurora.org Authentication-Results: mx.google.com; dkim=pass header.i=@codeaurora.org header.s=default header.b=FbTbFLra; dkim=pass header.i=@codeaurora.org header.s=default header.b=Vk0CYrdz; spf=pass (google.com: domain of vivek.gautam@codeaurora.org designates 198.145.29.96 as permitted sender) smtp.mailfrom=vivek.gautam@codeaurora.org DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 42A9C6014B Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=vivek.gautam@codeaurora.org Subject: Re: [PATCH v6 4/6] iommu/arm-smmu: Add the device_link between masters and smmu To: Robin Murphy , alex.williamson@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, rjw@rjwysocki.net, will.deacon@arm.com, iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, sboyd@codeaurora.org Cc: gregkh@linuxfoundation.org, sricharan@codeaurora.org, m.szyprowski@samsung.com, architt@codeaurora.org, linux-arm-msm@vger.kernel.org References: <1516362223-22946-1-git-send-email-vivek.gautam@codeaurora.org> <1516362223-22946-5-git-send-email-vivek.gautam@codeaurora.org> <6b930150-cb81-b0a5-601c-16cb576c4341@arm.com> From: Vivek Gautam Message-ID: Date: Thu, 1 Feb 2018 14:23:11 +0530 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.5.2 MIME-Version: 1.0 In-Reply-To: <6b930150-cb81-b0a5-601c-16cb576c4341@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1590021073891800456?= X-GMAIL-MSGID: =?utf-8?q?1591188074955072783?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi, On 1/31/2018 6:39 PM, Robin Murphy wrote: > On 19/01/18 11:43, Vivek Gautam wrote: >> From: Sricharan R >> >> Finally add the device link between the master device and >> smmu, so that the smmu gets runtime enabled/disabled only when the >> master needs it. This is done from add_device callback which gets >> called once when the master is added to the smmu. > > Don't we need to balance this with a device_link_del() in > .remove_device (like exynos-iommu does)? Right. Will add device_link_del() call. Thanks for pointing out. regards Vivek > > Robin. > >> Signed-off-by: Sricharan R >> --- >>   drivers/iommu/arm-smmu.c | 11 +++++++++++ >>   1 file changed, 11 insertions(+) >> >> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c >> index 95478bfb182c..33bbcfedb896 100644 >> --- a/drivers/iommu/arm-smmu.c >> +++ b/drivers/iommu/arm-smmu.c >> @@ -1367,6 +1367,7 @@ static int arm_smmu_add_device(struct device *dev) >>       struct arm_smmu_device *smmu; >>       struct arm_smmu_master_cfg *cfg; >>       struct iommu_fwspec *fwspec = dev->iommu_fwspec; >> +    struct device_link *link; >>       int i, ret; >>         if (using_legacy_binding) { >> @@ -1428,6 +1429,16 @@ static int arm_smmu_add_device(struct device >> *dev) >>         pm_runtime_put_sync(smmu->dev); >>   +    /* >> +     * Establish the link between smmu and master, so that the >> +     * smmu gets runtime enabled/disabled as per the master's >> +     * needs. >> +     */ >> +    link = device_link_add(dev, smmu->dev, DL_FLAG_PM_RUNTIME); >> +    if (!link) >> +        dev_warn(smmu->dev, "Unable to create device link between %s >> and %s\n", >> +             dev_name(smmu->dev), dev_name(dev)); >> + >>       return 0; >>     out_cfg_free: >>