Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752567AbdHRRBN (ORCPT ); Fri, 18 Aug 2017 13:01:13 -0400 Received: from mail-pg0-f45.google.com ([74.125.83.45]:35868 "EHLO mail-pg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750949AbdHRRBL (ORCPT ); Fri, 18 Aug 2017 13:01:11 -0400 Date: Fri, 18 Aug 2017 10:01:08 -0700 From: Brian Norris To: Jeffy Chen Cc: linux-kernel@vger.kernel.org, bhelgaas@google.com, shawn.lin@rock-chips.com, dianders@chromium.org, Heiko Stuebner , linux-pci@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Tony Lindgren Subject: Re: [RFC PATCH v2 1/3] PCI: rockchip: Add support for pcie wake irq Message-ID: <20170818170107.GA119461@google.com> References: <20170817120431.12398-1-jeffy.chen@rock-chips.com> <20170817120431.12398-2-jeffy.chen@rock-chips.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170817120431.12398-2-jeffy.chen@rock-chips.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3192 Lines: 101 + Tony On Thu, Aug 17, 2017 at 08:04:29PM +0800, Jeffy Chen wrote: > Add support for PCIE_WAKE pin in rockchip pcie driver. > > Signed-off-by: Jeffy Chen > --- > > Changes in v2: > Use dev_pm_set_dedicated_wake_irq > -- Suggested by Brian Norris > > drivers/pci/host/pcie-rockchip.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c > index 7bb9870f6d8c..c2b973c738fe 100644 > --- a/drivers/pci/host/pcie-rockchip.c > +++ b/drivers/pci/host/pcie-rockchip.c > @@ -36,6 +36,7 @@ > #include > #include > #include > +#include > #include > #include > > @@ -853,7 +854,6 @@ static void rockchip_pcie_legacy_int_handler(struct irq_desc *desc) > chained_irq_exit(chip, desc); > } > > - > /** > * rockchip_pcie_parse_dt - Parse Device Tree > * @rockchip: PCIe port information > @@ -1018,6 +1018,14 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip) > return err; > } > > + device_init_wakeup(dev, true); > + irq = platform_get_irq_byname(pdev, "wake"); > + if (irq >= 0) { > + err = dev_pm_set_dedicated_wake_irq(dev, irq); Did you test that this works out correctly as a level-triggered interrupt? IIUC, the dummy handler won't mask the interrupt, so it might keep firing. See: static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq) { struct wake_irq *wirq = _wirq; int res; /* Maybe abort suspend? */ if (irqd_is_wakeup_set(irq_get_irq_data(irq))) { pm_wakeup_event(wirq->dev, 0); return IRQ_HANDLED; <--- We can return here, with the trigger still asserted } ... This could cause some kind of an IRQ storm, including a lockup or significant slowdown, I think. BTW, in another context, Tony suggested we might need to fix up the IRQ flags like this: int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) { ... err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq, - IRQF_ONESHOT, dev_name(dev), wirq); + IRQF_ONESHOT | irq_get_trigger_type(irq), dev_name(dev), wirq); But IIUC, that's not actually necessary, because __setup_irq() automatically configures the trigger type if the driver didn't request one explicitly. Brian > + if (err) > + dev_err(dev, "failed to setup PCIe wake IRQ\n"); > + } > + > rockchip->vpcie3v3 = devm_regulator_get_optional(dev, "vpcie3v3"); > if (IS_ERR(rockchip->vpcie3v3)) { > if (PTR_ERR(rockchip->vpcie3v3) == -EPROBE_DEFER) > @@ -1524,6 +1532,9 @@ static int rockchip_pcie_remove(struct platform_device *pdev) > struct device *dev = &pdev->dev; > struct rockchip_pcie *rockchip = dev_get_drvdata(dev); > > + dev_pm_clear_wake_irq(dev); > + device_init_wakeup(dev, false); > + > pci_stop_root_bus(rockchip->root_bus); > pci_remove_root_bus(rockchip->root_bus); > pci_unmap_iospace(rockchip->io); > -- > 2.11.0 > >