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 4C534C74A5B for ; Sat, 18 Mar 2023 00:24:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229988AbjCRAYM (ORCPT ); Fri, 17 Mar 2023 20:24:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230047AbjCRAYI (ORCPT ); Fri, 17 Mar 2023 20:24:08 -0400 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6D760E4866; Fri, 17 Mar 2023 17:23:56 -0700 (PDT) Received: from pps.filterd (m0279868.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 32HN6ack006717; Sat, 18 Mar 2023 00:23:42 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=qcppdkim1; bh=YbJlbRd8JL1QZiWVWhmE/ZzDI8mZG6GyuQiWnEyG06s=; b=kETSDRgYjyYb7aGy0Nqd6EBy99LqQhJ6SLt5c4cTO9PO+/bJKIj9NC8DdcxW7u+gV3sh C7muKITMdS8aEl9BJKvjm19rea6BPqBaHsjz4S5Jrv11R1/MneYEPzo/tPibWDCrbhIf 8SZUykIfWPqnqHm+2IhRE+lwhDj+BXfT9nXtd6xHDOR2WMeLqau38BYdKWymm4t9jNeJ lleRlUCfROeIDf+Lkg59Jc4g89ghfzE0FZ4PE8GsRUdBpZASf1MMitlmpgzMrBqMxiLB 3sX1ld4ufVYKpmJ/a1Oc24KcLC7Mnpz6uNNSuQKDJ0dhUjHtrzJwtrIeLkAnH3tLol5v YQ== Received: from nalasppmta03.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3pce6nkr81-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 18 Mar 2023 00:23:41 +0000 Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA03.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 32I0NeBA026158 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 18 Mar 2023 00:23:40 GMT Received: from [10.110.60.126] (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.41; Fri, 17 Mar 2023 17:23:39 -0700 Message-ID: <2632a958-2750-c057-2606-c2541efff392@quicinc.com> Date: Fri, 17 Mar 2023 17:23:28 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH v12 6/6] usb: gadget: f_ecm: Add suspend/resume and remote wakeup support Content-Language: en-US To: Thinh Nguyen CC: "gregkh@linuxfoundation.org" , "linux-kernel@vger.kernel.org" , "linux-usb@vger.kernel.org" , "quic_wcheng@quicinc.com" , "quic_jackp@quicinc.com" References: <1679009888-8239-1-git-send-email-quic_eserrao@quicinc.com> <1679009888-8239-7-git-send-email-quic_eserrao@quicinc.com> <20230317001149.nlvcj2y3fuvq32qt@synopsys.com> <0bf5bddd-515b-76b6-f22f-9da10a140d83@quicinc.com> <20230317212831.bcapq26jnuk2vkws@synopsys.com> <20230317231956.w3kr3zcy44odxdko@synopsys.com> From: Elson Serrao In-Reply-To: <20230317231956.w3kr3zcy44odxdko@synopsys.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: hgVwyq6HDxT4RvMPC_OYm9ZzKv7mNncL X-Proofpoint-GUID: hgVwyq6HDxT4RvMPC_OYm9ZzKv7mNncL X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-03-17_20,2023-03-16_02,2023-02-09_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 adultscore=0 priorityscore=1501 spamscore=0 mlxlogscore=999 malwarescore=0 suspectscore=0 bulkscore=0 phishscore=0 impostorscore=0 clxscore=1015 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2303150002 definitions=main-2303180001 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/17/2023 4:20 PM, Thinh Nguyen wrote: > On Fri, Mar 17, 2023, Thinh Nguyen wrote: >> On Fri, Mar 17, 2023, Elson Serrao wrote: >>> >>> >>> On 3/16/2023 5:11 PM, Thinh Nguyen wrote: >>>> On Thu, Mar 16, 2023, Elson Roy Serrao wrote: >>>>> When host sends a suspend notification to the device, handle >>>>> the suspend callbacks in the function driver. Enhanced super >>>>> speed devices can support function suspend feature to put the >>>>> function in suspend state. Handle function suspend callback. >>>>> >>>>> Depending on the remote wakeup capability the device can either >>>>> trigger a remote wakeup or wait for the host initiated resume to >>>>> start data transfer again. >>>>> >>>>> Signed-off-by: Elson Roy Serrao >>>>> --- >>>>> drivers/usb/gadget/function/f_ecm.c | 71 +++++++++++++++++++++++++++++++++++ >>>>> drivers/usb/gadget/function/u_ether.c | 63 +++++++++++++++++++++++++++++++ >>>>> drivers/usb/gadget/function/u_ether.h | 4 ++ >>>>> 3 files changed, 138 insertions(+) >>>>> >>>>> diff --git a/drivers/usb/gadget/function/f_ecm.c b/drivers/usb/gadget/function/f_ecm.c >>>>> index a7ab30e..c43cd557 100644 >>>>> --- a/drivers/usb/gadget/function/f_ecm.c >>>>> +++ b/drivers/usb/gadget/function/f_ecm.c >>>>> @@ -633,6 +633,8 @@ static void ecm_disable(struct usb_function *f) >>>>> usb_ep_disable(ecm->notify); >>>>> ecm->notify->desc = NULL; >>>>> + f->func_suspended = false; >>>>> + f->func_wakeup_armed = false; >>>>> } >>>>> /*-------------------------------------------------------------------------*/ >>>>> @@ -885,6 +887,71 @@ static struct usb_function_instance *ecm_alloc_inst(void) >>>>> return &opts->func_inst; >>>>> } >>>>> +static void ecm_suspend(struct usb_function *f) >>>>> +{ >>>>> + struct f_ecm *ecm = func_to_ecm(f); >>>>> + struct usb_composite_dev *cdev = ecm->port.func.config->cdev; >>>>> + >>>>> + if (f->func_suspended) { >>>>> + DBG(cdev, "Function already suspended\n"); >>>>> + return; >>>>> + } >>>>> + >>>>> + DBG(cdev, "ECM Suspend\n"); >>>>> + >>>>> + gether_suspend(&ecm->port); >>>>> +} >>>>> + >>>>> +static void ecm_resume(struct usb_function *f) >>>>> +{ >>>>> + struct f_ecm *ecm = func_to_ecm(f); >>>>> + struct usb_composite_dev *cdev = ecm->port.func.config->cdev; >>>>> + >>>>> + /* >>>>> + * If the function is in USB3 Function Suspend state, resume is >>>>> + * canceled. In this case resume is done by a Function Resume request. >>>>> + */ >>>>> + if (f->func_suspended) >>>>> + return; >>>>> + >>>>> + DBG(cdev, "ECM Resume\n"); >>>>> + >>>>> + gether_resume(&ecm->port); >>>>> +} >>>>> + >>>>> +static int ecm_get_status(struct usb_function *f) >>>>> +{ >>>>> + struct usb_configuration *c = f->config; >>>>> + >>>>> + /* D0 and D1 bit set to 0 if device is not wakeup capable */ >>>>> + if (!(USB_CONFIG_ATT_WAKEUP & c->bmAttributes)) >>>>> + return 0; >>>>> + >>>>> + return (f->func_wakeup_armed ? USB_INTRF_STAT_FUNC_RW : 0) | >>>>> + USB_INTRF_STAT_FUNC_RW_CAP; >>>>> +} >>>> >>>> Why do we need to implement ecm_get_status if it's already handled in >>>> composite.c now? >>>> >>> >>> Yes this can be removed now. Will modify accordingly. >>>>> + >>>>> +static int ecm_func_suspend(struct usb_function *f, u8 options) >>>>> +{ >>>>> + struct usb_composite_dev *cdev = f->config->cdev; >>>>> + >>>>> + DBG(cdev, "func susp %u cmd\n", options); >>>>> + >>>>> + if (options & (USB_INTRF_FUNC_SUSPEND_LP >> 8)) { >>>> >>>> This feature selector doesn't indicate whether it's SetFeature or >>>> ClearFeature request. ecm_func_suspend is supposed to be for >>>> SetFeature(suspend) only. Perhaps we may have to define func_resume() >>>> for ClearFeature(suspend)? >>>> >> >>> Host uses the same feature selector FUNCTION_SUSPEND for function suspend >>> and function resume and func_suspend() callback can be used to >>> handle both the cases ? The distinction comes whether it is a >> >> How do you plan to handle that? Pass this info in some unused/reserved >> bit of the "options" argument? Introduce a new parameter to the >> func_suspend()? >> >> If that's the case, then you need to update the document on >> func_suspend() to also support ClearFeature(suspend). Right now it's >> documented for SetFeature only. Also, make sure that other existing >> function drivers will not break because of the change of the >> func_suspend behavior. >> >>> SetFeature(FUNCTION_SUSPEND) or ClearFeature(FUNCTION_SUSPEND) which can be >>> easily done in the func_suspend callback itself. We can add another callback >>> func_resume specific to ClearFeature(FUNCTION_SUSPEND) but wont that be >>> redundant and more callback handling on function driver/composite side as >>> well? Please let me know your opinion. >>> >> >> We actually didn't properly define func_suspend and its counter part. It >> seems cleaner to me to introduce func_resume as it seems more intuitive >> and easier to read. Let me know how you plan to use func_suspend() for >> both cases. >> > > How about we handle function suspend resume in composite also? I mean > something like this: > > diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c > index 36add1879ed2..79dc055eb5f7 100644 > --- a/drivers/usb/gadget/composite.c > +++ b/drivers/usb/gadget/composite.c > @@ -1948,9 +1948,18 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) > f = cdev->config->interface[intf]; > if (!f) > break; > - status = f->get_status ? f->get_status(f) : 0; > - if (status < 0) > - break; > + > + if (f->get_status) { > + status = f->get_status(f); > + if (status < 0) > + break; > + } else { > + if (f->config->bmAttributes & USB_CONFIG_ATT_WAKEUP) { > + status |= USB_INTRF_STAT_FUNC_RW_CAP; > + if (f->func_wakeup_armed) > + status |= USB_INTRF_STAT_FUNC_RW; > + } > + } > put_unaligned_le16(status & 0x0000ffff, req->buf); > break; > /* > @@ -1971,9 +1980,28 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) > f = cdev->config->interface[intf]; > if (!f) > break; > + if (w_index & USB_INTRF_FUNC_SUSPEND_RW) { > + if (!(f->config->bmAttributes & USB_CONFIG_ATT_WAKEUP)) > + break; > + > + f->func_wakeup_armed = (ctrl->bRequest == USB_REQ_SET_FEATURE); > + } > + > value = 0; > - if (f->func_suspend) > + if (f->func_suspend) { > value = f->func_suspend(f, w_index >> 8); > + } else if (w_index & USB_INTRF_FUNC_SUSPEND_LP) { > + if (f->suspend && && !f->func_suspended && > + ctrl->bRequest == USB_REQ_SET_FEATURE)) { > + f->suspend(f); > + f->func_suspended = true; > + } else if (f->resume && f->func_suspended && > + ctrl->bRequest == USB_REQ_CLEAR_FEATURE_FEATURE)) { > + f->resume(f); > + f->func_suspended = false; > + } > + } > + > if (value < 0) { > ERROR(cdev, > "func_suspend() returned error %d\n", > At individual function driver level there is no need to differentiate between suspend() and func_suspend() APIs, as both are intended to put the function in suspend state. So your idea/implementation above makes it much more clearer. Let composite also handle this and call either f->suspend() or f->resume() callback based on the setup packet received. Thank you for this suggestion. > > Also, do we need the f->func_suspended flag? we'd need the remote wakeup > flag for the status, but when do we need f->func_suspended? It seems > like it can be handled within the function driver's scope. f->func_suspended flag I had added for below purposes 1.) Function drivers should know the right wakeup() op to be called. That is if they are in FUNC_SUSPEND then call usb_func_wakeup() and if they are in device suspend then call usb_gadget_wakeup(). (we can use f->func_wakeup_armed flag for this purpose as well) 2.) If a function is in USB3 FUNCTION_SUSPEND state then it shouldn't allow f->resume() called through composite_resume() as the exit from FUNCTION_SUSPEND state is via ClearFeature(FUNCTION_SUSPEND). So we need a way to tell function drivers if they are in USB3 FUNCTION_SUSPEND state OR device suspend. Please let me know if you see any alternative or better approach here. Thanks Elson