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 9754BC433EF for ; Wed, 29 Dec 2021 20:12:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231733AbhL2UMd (ORCPT ); Wed, 29 Dec 2021 15:12:33 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:60692 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231701AbhL2UMc (ORCPT ); Wed, 29 Dec 2021 15:12:32 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2C294614B3; Wed, 29 Dec 2021 20:12:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41703C36AE9; Wed, 29 Dec 2021 20:12:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1640808751; bh=vWtanjbewujinnsoAkIMuVPTzg/CYmtOfG32HMGoOIM=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=ri2QRYB/7J/7LVZ8rfiwgnIizpgwLsLMSsLF3cm4tBjkhVFJrtTto93EM18va0Yqr FYhWUXtXuIcM5kYowDEonIa23f+MV8wNNdNhi9rHljv2F64NfNznxlJP5uuPmNlxN3 we4bma2po+ck6Pxx3nWUGOX/bl5iZ9kbKO+I3mXRKGGsoqNBYEE3+9mpXYmfRvkSmb MfKwkkCRLPNJZ8WvnSrldTdF07hOG1th8BRnvWCOm5BW7Y2d41ctz6KoEjpnWDCJEo NznV53lorTyejhVUqJgmARWf/NOxYjP1+bea/FKfvni2Hr302VZXjHejIp1Vx/FSdd JMKiG/5vDQgag== Date: Wed, 29 Dec 2021 14:12:29 -0600 From: Bjorn Helgaas To: Kai-Heng Feng Cc: m.chetan.kumar@intel.com, linuxwwan@intel.com, linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, Loic Poulain , Sergey Ryazanov , Johannes Berg , "David S. Miller" , Jakub Kicinski , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Vaibhav Gupta , "Rafael J. Wysocki" Subject: Re: [PATCH 1/2] net: wwan: iosm: Let PCI core handle PCI power transition Message-ID: <20211229201229.GA1698801@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211224081914.345292-1-kai.heng.feng@canonical.com> Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org [+cc Rafael, in case you have insight about the PCI_D0 question below; Vaibhav, since this is related to your generic PM conversions] On Fri, Dec 24, 2021 at 04:19:13PM +0800, Kai-Heng Feng wrote: > pci_pm_suspend_noirq() and pci_pm_resume_noirq() already handle power > transition for system-wide suspend and resume, so it's not necessary to > do it in the driver. I see DaveM has already applied this, but it looks good to me, thanks for doing this! One minor question below... > Signed-off-by: Kai-Heng Feng > --- > drivers/net/wwan/iosm/iosm_ipc_pcie.c | 49 ++------------------------- > 1 file changed, 2 insertions(+), 47 deletions(-) > > diff --git a/drivers/net/wwan/iosm/iosm_ipc_pcie.c b/drivers/net/wwan/iosm/iosm_ipc_pcie.c > index 2fe88b8be3481..d73894e2a84ed 100644 > --- a/drivers/net/wwan/iosm/iosm_ipc_pcie.c > +++ b/drivers/net/wwan/iosm/iosm_ipc_pcie.c > @@ -363,67 +363,22 @@ static int __maybe_unused ipc_pcie_resume_s2idle(struct iosm_pcie *ipc_pcie) > > int __maybe_unused ipc_pcie_suspend(struct iosm_pcie *ipc_pcie) > { > - struct pci_dev *pdev; > - int ret; > - > - pdev = ipc_pcie->pci; > - > - /* Execute D3 one time. */ > - if (pdev->current_state != PCI_D0) { > - dev_dbg(ipc_pcie->dev, "done for PM=%d", pdev->current_state); > - return 0; > - } I don't understand the intent of this early exit, and it's not obvious to me that pci_pm_suspend_noirq() bails out early when (pdev->current_state != PCI_D0). > /* The HAL shall ask the shared memory layer whether D3 is allowed. */ > ipc_imem_pm_suspend(ipc_pcie->imem); > > - /* Save the PCI configuration space of a device before suspending. */ > - ret = pci_save_state(pdev); > - > - if (ret) { > - dev_err(ipc_pcie->dev, "pci_save_state error=%d", ret); > - return ret; > - } > - > - /* Set the power state of a PCI device. > - * Transition a device to a new power state, using the device's PCI PM > - * registers. > - */ > - ret = pci_set_power_state(pdev, PCI_D3cold); > - > - if (ret) { > - dev_err(ipc_pcie->dev, "pci_set_power_state error=%d", ret); > - return ret; > - } > - > dev_dbg(ipc_pcie->dev, "SUSPEND done"); > - return ret; > + return 0; > } > > int __maybe_unused ipc_pcie_resume(struct iosm_pcie *ipc_pcie) > { > - int ret; > - > - /* Set the power state of a PCI device. > - * Transition a device to a new power state, using the device's PCI PM > - * registers. > - */ > - ret = pci_set_power_state(ipc_pcie->pci, PCI_D0); > - > - if (ret) { > - dev_err(ipc_pcie->dev, "pci_set_power_state error=%d", ret); > - return ret; > - } > - > - pci_restore_state(ipc_pcie->pci); > - > /* The HAL shall inform the shared memory layer that the device is > * active. > */ > ipc_imem_pm_resume(ipc_pcie->imem); > > dev_dbg(ipc_pcie->dev, "RESUME done"); > - return ret; > + return 0; > } > > static int __maybe_unused ipc_pcie_suspend_cb(struct device *dev) > -- > 2.33.1 >