From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754582AbbGFS2B (ORCPT ); Mon, 6 Jul 2015 14:28:01 -0400 Received: from mail-ie0-f181.google.com ([209.85.223.181]:34946 "EHLO mail-ie0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754162AbbGFS1j (ORCPT ); Mon, 6 Jul 2015 14:27:39 -0400 From: Douglas Anderson To: Greg Kroah-Hartman , John Youn , Felipe Balbi Cc: linux-usb@vger.kernel.org, Chris Zhong , Heiko Stuebner , Julius Werner , Andrew Bresticker , Alexandru Stan , lyz@rock-chips.com, linux-rockchip@lists.infradead.org, Douglas Anderson , linux-kernel@vger.kernel.org Subject: [REPOST PATCH 3/3] USB: dwc2: Don't turn off the usbphy in suspend if wakeup is enabled Date: Mon, 6 Jul 2015 11:27:04 -0700 Message-Id: <1436207224-21849-4-git-send-email-dianders@chromium.org> X-Mailer: git-send-email 2.4.3.573.g4eafbef In-Reply-To: <1436207224-21849-1-git-send-email-dianders@chromium.org> References: <1436207224-21849-1-git-send-email-dianders@chromium.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the 'snps,need-phy-for-wake' is set in the device tree then: - We know that we can wakeup, so call device_set_wakeup_capable(). The USB core will use this knowledge to enable wakeup by default. - We know that we should keep the PHY on during suspend if something on our root hub needs remote wakeup. This requires the patch (USB: Export usb_wakeup_enabled_descendants()). Note that we don't keep the PHY on at suspend time if it's not needed because it would be a power draw. If we later find some users of dwc2 that can support wakeup without keeping the PHY on we may want to add a way to call device_set_wakeup_capable() without keeping the PHY on at suspend time. Signed-off-by: Chris Zhong Signed-off-by: Douglas Anderson --- drivers/usb/dwc2/core.h | 2 ++ drivers/usb/dwc2/platform.c | 45 +++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 45 insertions(+), 2 deletions(-) diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index 53b8de0..b60a1e8 100644 --- a/drivers/usb/dwc2/core.h +++ b/drivers/usb/dwc2/core.h @@ -687,6 +687,8 @@ struct dwc2_hsotg { enum usb_dr_mode dr_mode; unsigned int hcd_enabled:1; unsigned int gadget_enabled:1; + unsigned int need_phy_for_wake:1; + unsigned int phy_off_for_suspend:1; struct phy *phy; struct usb_phy *uphy; diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c index 9093530..38fce75 100644 --- a/drivers/usb/dwc2/platform.c +++ b/drivers/usb/dwc2/platform.c @@ -42,7 +42,9 @@ #include #include #include +#include +#include #include #include "core.h" @@ -222,6 +224,10 @@ static int dwc2_driver_probe(struct platform_device *dev) hsotg->dr_mode = of_usb_get_dr_mode(dev->dev.of_node); + hsotg->need_phy_for_wake = + of_property_read_bool(dev->dev.of_node, + "snps,need-phy-for-wake"); + /* * Attempt to find a generic PHY, then look for an old style * USB PHY @@ -265,6 +271,14 @@ static int dwc2_driver_probe(struct platform_device *dev) hsotg->gadget_enabled = 1; } + /* + * If we need PHY for wakeup we must be wakeup capable. + * When we have a device that can wake without the PHY we + * can adjust this condition. + */ + if (hsotg->need_phy_for_wake) + device_set_wakeup_capable(&dev->dev, true); + if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) { retval = dwc2_hcd_init(hsotg, irq); if (retval) { @@ -282,6 +296,28 @@ static int dwc2_driver_probe(struct platform_device *dev) return retval; } +static bool __maybe_unused dwc2_can_poweroff_phy(struct dwc2_hsotg *dwc2) +{ + struct usb_device *root_hub = dwc2_hsotg_to_hcd(dwc2)->self.root_hub; + + if (dwc2->lx_state == DWC2_L0) + return false; + + /* If the controller isn't allowed to wakeup then we can power off. */ + if (!device_may_wakeup(dwc2->dev)) + return true; + + /* + * We don't want to power off the PHY if something under the + * root hub has wakeup enabled. + */ + if (usb_wakeup_enabled_descendants(root_hub)) + return false; + + /* No reason to keep the PHY powered, so allow poweroff */ + return true; +} + static int __maybe_unused dwc2_suspend(struct device *dev) { struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev); @@ -290,8 +326,10 @@ static int __maybe_unused dwc2_suspend(struct device *dev) if (dwc2_is_device_mode(dwc2)) { ret = s3c_hsotg_suspend(dwc2); } else { - if (dwc2->lx_state == DWC2_L0) + if (!dwc2_can_poweroff_phy(dwc2)) return 0; + + dwc2->phy_off_for_suspend = true; phy_exit(dwc2->phy); phy_power_off(dwc2->phy); @@ -307,9 +345,12 @@ static int __maybe_unused dwc2_resume(struct device *dev) if (dwc2_is_device_mode(dwc2)) { ret = s3c_hsotg_resume(dwc2); } else { + if (!dwc2->phy_off_for_suspend) + return ret; + phy_power_on(dwc2->phy); phy_init(dwc2->phy); - + dwc2->phy_off_for_suspend = false; } return ret; } -- 2.4.3.573.g4eafbef