From patchwork Tue Aug 2 19:18:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elson Roy Serrao X-Patchwork-Id: 595073 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 3D998C19F2C for ; Tue, 2 Aug 2022 19:18:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230512AbiHBTSr (ORCPT ); Tue, 2 Aug 2022 15:18:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230300AbiHBTSp (ORCPT ); Tue, 2 Aug 2022 15:18:45 -0400 Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F82713CD9; Tue, 2 Aug 2022 12:18:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1659467924; x=1691003924; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=rQ6Hq/Z43PzcHLHa0X0VopuTrR/clg6tyIPhusfsMT4=; b=KBBy+rqnKloSuXRXUIzsQF794GpqDOmAF8cdY0KJXhoXTgZPiMb6i/2H fULkoaVPd7RzuNnTVB9iIMY/cI4m/CRaM6JuT/BGqG4BMk4PH1mdQBSKK kRVmK0YIivCNF02WoqfUa80jqEC+rMDLqM/lxbrReoq1HRCkXM04y3RJR g=; Received: from ironmsg09-lv.qualcomm.com ([10.47.202.153]) by alexa-out.qualcomm.com with ESMTP; 02 Aug 2022 12:18:42 -0700 X-QCInternal: smtphost Received: from hu-eserrao-lv.qualcomm.com (HELO hu-devc-lv-c.qualcomm.com) ([10.47.235.164]) by ironmsg09-lv.qualcomm.com with ESMTP; 02 Aug 2022 12:18:42 -0700 Received: by hu-devc-lv-c.qualcomm.com (Postfix, from userid 464172) id 7263D2106D; Tue, 2 Aug 2022 12:18:42 -0700 (PDT) From: Elson Roy Serrao To: balbi@kernel.org, gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, quic_wcheng@quicinc.com, quic_jackp@quicinc.com, quic_mrana@quicinc.com, Thinh.Nguyen@synopsys.com, Elson Roy Serrao Subject: [PATCH 1/5] usb: dwc3: Add remote wakeup handling Date: Tue, 2 Aug 2022 12:18:36 -0700 Message-Id: <1659467920-9095-2-git-send-email-quic_eserrao@quicinc.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1659467920-9095-1-git-send-email-quic_eserrao@quicinc.com> References: <1659467920-9095-1-git-send-email-quic_eserrao@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org An usb device can initate a remote wakeup and bring the link out of suspend as dictated by the DEVICE_REMOTE_WAKEUP feature selector. Add support to handle this packet and set the remote wakeup capability accordingly. Some hosts may take longer time to initiate the resume signaling after device triggers a remote wakeup. So improve the gadget_wakeup op to interrupt based rather than polling based by enabling link status change events. Signed-off-by: Elson Roy Serrao --- drivers/usb/dwc3/core.h | 4 +++ drivers/usb/dwc3/ep0.c | 4 +++ drivers/usb/dwc3/gadget.c | 69 ++++++++++++++++++++++++++++++++++++++++++++--- 3 files changed, 74 insertions(+), 3 deletions(-) diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 4fe4287..3306b1c 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -1113,6 +1113,8 @@ struct dwc3_scratchpad_array { * address. * @num_ep_resized: carries the current number endpoints which have had its tx * fifo resized. + * @is_remote_wakeup_enabled: remote wakeup status from host perspective + * @is_gadget_wakeup: remote wakeup requested via gadget op. */ struct dwc3 { struct work_struct drd_work; @@ -1326,6 +1328,8 @@ struct dwc3 { int max_cfg_eps; int last_fifo_depth; int num_ep_resized; + bool is_remote_wakeup_enabled; + bool is_gadget_wakeup; }; #define INCRX_BURST_MODE 0 diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c index 197af63..4cc3d3a 100644 --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -353,6 +353,9 @@ static int dwc3_ep0_handle_status(struct dwc3 *dwc, usb_status |= 1 << USB_DEV_STAT_U1_ENABLED; if (reg & DWC3_DCTL_INITU2ENA) usb_status |= 1 << USB_DEV_STAT_U2_ENABLED; + } else { + usb_status |= dwc->is_remote_wakeup_enabled << + USB_DEVICE_REMOTE_WAKEUP; } break; @@ -473,6 +476,7 @@ static int dwc3_ep0_handle_device(struct dwc3 *dwc, switch (wValue) { case USB_DEVICE_REMOTE_WAKEUP: + dwc->is_remote_wakeup_enabled = set; break; /* * 9.4.1 says only for SS, in AddressState only for diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 4366c45..d6697da 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2232,6 +2232,22 @@ static const struct usb_ep_ops dwc3_gadget_ep_ops = { /* -------------------------------------------------------------------------- */ +static void linksts_change_events_set(struct dwc3 *dwc, bool set) +{ + u32 reg; + + reg = dwc3_readl(dwc->regs, DWC3_DEVTEN); + if (set) + reg |= DWC3_DEVTEN_ULSTCNGEN; + else + reg &= ~DWC3_DEVTEN_ULSTCNGEN; + + dwc3_writel(dwc->regs, DWC3_DEVTEN, reg); + + /* Required to complete this operation before returning */ + mb(); +} + static int dwc3_gadget_get_frame(struct usb_gadget *g) { struct dwc3 *dwc = gadget_to_dwc(g); @@ -2270,9 +2286,13 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc) return -EINVAL; } + linksts_change_events_set(dwc, true); + ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV); if (ret < 0) { dev_err(dwc->dev, "failed to put link in Recovery\n"); + linksts_change_events_set(dwc, false); + dwc->is_gadget_wakeup = false; return ret; } @@ -2284,9 +2304,15 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc) dwc3_writel(dwc->regs, DWC3_DCTL, reg); } + /* If remote wakeup is triggered from function driver, bail out. + * Since link status change events are enabled we would receive + * an U0 event when wakeup is successful. + */ + if (dwc->is_gadget_wakeup) + return -EAGAIN; + /* poll until Link State changes to ON */ retries = 20000; - while (retries--) { reg = dwc3_readl(dwc->regs, DWC3_DSTS); @@ -2295,6 +2321,8 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc) break; } + linksts_change_events_set(dwc, false); + if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) { dev_err(dwc->dev, "failed to send remote wakeup\n"); return -EINVAL; @@ -2310,7 +2338,20 @@ static int dwc3_gadget_wakeup(struct usb_gadget *g) int ret; spin_lock_irqsave(&dwc->lock, flags); + if (g->speed < USB_SPEED_SUPER && !dwc->is_remote_wakeup_enabled) { + dev_err(dwc->dev, "%s:remote wakeup not supported\n", __func__); + ret = -EPERM; + goto out; + } + if (dwc->is_gadget_wakeup) { + dev_err(dwc->dev, "%s: remote wakeup in progress\n", __func__); + ret = -EINVAL; + goto out; + } + dwc->is_gadget_wakeup = true; ret = __dwc3_gadget_wakeup(dwc); + +out: spin_unlock_irqrestore(&dwc->lock, flags); return ret; @@ -2766,6 +2807,9 @@ static int dwc3_gadget_start(struct usb_gadget *g, spin_lock_irqsave(&dwc->lock, flags); dwc->gadget_driver = driver; + linksts_change_events_set(dwc, false); + dwc->is_remote_wakeup_enabled = false; + dwc->is_gadget_wakeup = false; spin_unlock_irqrestore(&dwc->lock, flags); return 0; @@ -2785,6 +2829,9 @@ static int dwc3_gadget_stop(struct usb_gadget *g) spin_lock_irqsave(&dwc->lock, flags); dwc->gadget_driver = NULL; + linksts_change_events_set(dwc, false); + dwc->is_remote_wakeup_enabled = false; + dwc->is_gadget_wakeup = false; dwc->max_cfg_eps = 0; spin_unlock_irqrestore(&dwc->lock, flags); @@ -3768,6 +3815,8 @@ static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc) usb_gadget_set_state(dwc->gadget, USB_STATE_NOTATTACHED); dwc->connected = false; + linksts_change_events_set(dwc, false); + dwc->is_gadget_wakeup = false; } static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc) @@ -3855,6 +3904,10 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc) reg = dwc3_readl(dwc->regs, DWC3_DCFG); reg &= ~(DWC3_DCFG_DEVADDR_MASK); dwc3_writel(dwc->regs, DWC3_DCFG, reg); + + dwc->is_remote_wakeup_enabled = false; + linksts_change_events_set(dwc, false); + dwc->is_gadget_wakeup = false; } static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc) @@ -3998,8 +4051,9 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc) */ } -static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc) +static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc, unsigned int evtinfo) { + enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK; /* * TODO take core out of low power mode when that's * implemented. @@ -4010,6 +4064,8 @@ static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc) dwc->gadget_driver->resume(dwc->gadget); spin_lock(&dwc->lock); } + + dwc->link_state = next; } static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc, @@ -4091,6 +4147,13 @@ static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc, } switch (next) { + case DWC3_LINK_STATE_U0: + if (dwc->is_gadget_wakeup) { + linksts_change_events_set(dwc, false); + dwc3_resume_gadget(dwc); + dwc->is_gadget_wakeup = false; + } + break; case DWC3_LINK_STATE_U1: if (dwc->speed == USB_SPEED_SUPER) dwc3_suspend_gadget(dwc); @@ -4159,7 +4222,7 @@ static void dwc3_gadget_interrupt(struct dwc3 *dwc, dwc3_gadget_conndone_interrupt(dwc); break; case DWC3_DEVICE_EVENT_WAKEUP: - dwc3_gadget_wakeup_interrupt(dwc); + dwc3_gadget_wakeup_interrupt(dwc, event->event_info); break; case DWC3_DEVICE_EVENT_HIBER_REQ: if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,