Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965458AbcJYBbE (ORCPT ); Mon, 24 Oct 2016 21:31:04 -0400 Received: from us01smtprelay-2.synopsys.com ([198.182.60.111]:41331 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932496AbcJYBbB (ORCPT ); Mon, 24 Oct 2016 21:31:01 -0400 Subject: Re: [PATCH v9 1/2] usb: dwc2: assert phy reset when waking up in rk3288 platform To: ayaka , John Youn , "linux-usb@vger.kernel.org" , "kishon@ti.com" References: <1476988627-14953-1-git-send-email-ayaka@soulik.info> <1476988627-14953-2-git-send-email-ayaka@soulik.info> <4ee5817d-0076-9974-8b0e-182a0241e1f5@synopsys.com> <922d7f12-a520-7c07-bc4c-887321177c6d@soulik.info> From: John Youn CC: "felipe.balbi@linux.intel.com" , "mark.rutland@arm.com" , "devicetree@vger.kernel.org" , "heiko@sntech.de" , "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "robh+dt@kernel.org" , "randy.li@rock-chips.com" Message-ID: <9a5d53a8-6c64-804a-0b47-7d7f24e9aa88@synopsys.com> Date: Mon, 24 Oct 2016 18:30:57 -0700 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <922d7f12-a520-7c07-bc4c-887321177c6d@soulik.info> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.9.139.69] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4633 Lines: 122 On 10/23/2016 2:33 AM, ayaka wrote: > > > On 10/22/2016 03:27 AM, John Youn wrote: >> On 10/20/2016 11:38 AM, Randy Li wrote: >>> On the rk3288 USB host-only port (the one that's not the OTG-enabled >>> port) the PHY can get into a bad state when a wakeup is asserted (not >>> just a wakeup from full system suspend but also a wakeup from >>> autosuspend). >>> >>> We can get the PHY out of its bad state by asserting its "port reset", >>> but unfortunately that seems to assert a reset onto the USB bus so it >>> could confuse things if we don't actually deenumerate / reenumerate the >>> device. >>> >>> We can also get the PHY out of its bad state by fully resetting it using >>> the reset from the CRU (clock reset unit) in chip, which does a more full >>> reset. The CRU-based reset appears to actually cause devices on the bus >>> to be removed and reinserted, which fixes the problem (albeit in a hacky >>> way). >>> >>> It's unfortunate that we need to do a full re-enumeration of devices at >>> wakeup time, but this is better than alternative of letting the bus get >>> wedged. >>> >>> Signed-off-by: Randy Li >>> --- >>> drivers/usb/dwc2/core.h | 1 + >>> drivers/usb/dwc2/core_intr.c | 11 +++++++++++ >>> drivers/usb/dwc2/platform.c | 9 +++++++++ >>> 3 files changed, 21 insertions(+) >>> >>> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h >>> index 2a21a04..e91ddbc 100644 >>> --- a/drivers/usb/dwc2/core.h >>> +++ b/drivers/usb/dwc2/core.h >>> @@ -859,6 +859,7 @@ struct dwc2_hsotg { >>> unsigned int ll_hw_enabled:1; >>> >>> struct phy *phy; >>> + struct work_struct phy_rst_work; >>> struct usb_phy *uphy; >>> struct dwc2_hsotg_plat *plat; >>> struct regulator_bulk_data supplies[ARRAY_SIZE(dwc2_hsotg_supply_names)]; >>> diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c >>> index d85c5c9..c3d2168 100644 >>> --- a/drivers/usb/dwc2/core_intr.c >>> +++ b/drivers/usb/dwc2/core_intr.c >>> @@ -345,6 +345,7 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg) >>> static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) >>> { >>> int ret; >>> + struct device_node *np = hsotg->dev->of_node; >>> >>> /* Clear interrupt */ >>> dwc2_writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS); >>> @@ -379,6 +380,16 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg) >>> /* Restart the Phy Clock */ >>> pcgcctl &= ~PCGCTL_STOPPCLK; >>> dwc2_writel(pcgcctl, hsotg->regs + PCGCTL); >>> + >>> + /* >>> + * It is a quirk in Rockchip RK3288, causing by >>> + * a hardware bug. This will propagate out and >>> + * eventually we'll re-enumerate the device. >>> + * Not great but the best we can do >>> + */ >>> + if (of_device_is_compatible(np, "rockchip,rk3288-usb")) >>> + schedule_work(&hsotg->phy_rst_work); >>> + >>> mod_timer(&hsotg->wkp_timer, >>> jiffies + msecs_to_jiffies(71)); >>> } else { >>> diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c >>> index 8e1728b..65953cf 100644 >>> --- a/drivers/usb/dwc2/platform.c >>> +++ b/drivers/usb/dwc2/platform.c >>> @@ -366,6 +366,14 @@ int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg) >>> return ret; >>> } >>> >>> +/* Only used to reset usb phy at interrupter runtime */ >>> +static void dwc2_reset_phy_work(struct work_struct *data) >>> +{ >>> + struct dwc2_hsotg *hsotg = container_of(data, struct dwc2_hsotg, >>> + phy_rst_work); >>> + phy_reset(hsotg->phy); >>> +} >>> + >>> static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg) >>> { >>> int i, ret; >>> @@ -410,6 +418,7 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg) >>> return ret; >>> } >>> } >>> + INIT_WORK(&hsotg->phy_rst_work, dwc2_reset_phy_work); >>> >>> if (!hsotg->phy) { >>> hsotg->uphy = devm_usb_get_phy(hsotg->dev, USB_PHY_TYPE_USB2); >>> >> Hi Randy, >> >> This fails compile if CONFIG_GENERIC_PHY is disabled. I think you need >> to make a fix to your phy_reset patch first. > In the last time, cac18ecb6f44b11bc303d7afbae3887b27938fa4 have not been > merged, I though the > [PATCH v8 1/3] phy: Add reset callback for not generic phy have been > merged before that. when the rebase abandon it. > Should re-send that patch? As the mainline have not been affected, could > you arrange a squash for it? Hi Randy, Can you resend the fix to Kishon? The phy_reset patch landed in 4.9-rc so I think he should take the fix for the next -rc. After that we can send the dwc2 change through Felipe. Regards, John