From patchwork Tue Jul 26 00:58:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vicki Pfau X-Patchwork-Id: 12928546 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 A16B7C43334 for ; Tue, 26 Jul 2022 01:08:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231665AbiGZBI2 (ORCPT ); Mon, 25 Jul 2022 21:08:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230130AbiGZBI1 (ORCPT ); Mon, 25 Jul 2022 21:08:27 -0400 X-Greylist: delayed 519 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 25 Jul 2022 18:08:25 PDT Received: from endrift.com (endrift.com [173.255.198.10]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77C5B27FE7 for ; Mon, 25 Jul 2022 18:08:25 -0700 (PDT) Received: from localhost.localdomain (c-73-100-220-23.hsd1.ma.comcast.net [73.100.220.23]) by endrift.com (Postfix) with ESMTPSA id 37588A2A0; Mon, 25 Jul 2022 17:59:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=endrift.com; s=2020; t=1658797186; bh=4k4dBaKSGveA16isbS3KL3AqRhTfNDtH6wpw0BZSGys=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sPUrWtCN6WzqP2Y4WlgzGsrFuqvenA+FVGgZzxlSbQzvcUOfn9A9udNFdxfHAT3F9 3BcqmVVFRNVShG6BDc0CGhQgATWZVJ0O3CY4prvBA07inGeNf0EgGQMBcZzCrUJAo2 IjnjeJja01ul5EtDvNM78ZvgZyJNfqU8yA1kdkTdh1gDl/gcvn0vV94uS9FaoDWtHW TSn8NuFGpoYWOtOa+HYpsekg319Kgfjufe3GjWO/bpQIhY2/1477b64UCh1gzCJcaL 49Qq8AUUSk7ZFjZ8jSRuuIGZfajrlZmrWNMW+26Nnn4JDfIaANPO0HCtpZ/WgunZux C63e/U1GJ5BNA== From: Vicki Pfau To: Felipe Balbi , Greg Kroah-Hartman , Maxim Devaev , linux-usb@vger.kernel.org Cc: Vicki Pfau Subject: [PATCH 2/2] USB: gadget: f_hid: Add Set-Feature report Date: Mon, 25 Jul 2022 17:58:26 -0700 Message-Id: <20220726005824.2817646-2-vi@endrift.com> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220726005824.2817646-1-vi@endrift.com> References: <20220726005824.2817646-1-vi@endrift.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org While the HID gadget implementation has been sufficient for devices that only use INTERRUPT transfers, the USB HID standard includes provisions for Set- and Get-Feature report CONTROL transfers that go over endpoint 0. These were previously impossible with the existing implementation, and would either send an empty reply, or stall out. As the feature is a standard part of USB HID, it stands to reason that devices would use it, and that the HID gadget should support it. This patch adds support for host-to-device Set-Feature reports through a new ioctl interface to the hidg class dev nodes. Signed-off-by: Vicki Pfau --- drivers/usb/gadget/function/f_hid.c | 112 ++++++++++++++++++++++++++-- include/uapi/linux/usb/g_hid.h | 1 + 2 files changed, 105 insertions(+), 8 deletions(-) diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c index 7e70e4a168e6..97aa56206020 100644 --- a/drivers/usb/gadget/function/f_hid.c +++ b/drivers/usb/gadget/function/f_hid.c @@ -72,6 +72,11 @@ struct f_hidg { wait_queue_head_t write_queue; struct usb_request *req; + /* set report */ + struct list_head completed_set_req; + spinlock_t set_spinlock; + wait_queue_head_t set_queue; + /* get report */ struct usb_request *get_req; struct usb_hidg_report get_report; @@ -519,6 +524,54 @@ static ssize_t f_hidg_write(struct file *file, const char __user *buffer, return status; } +static int f_hidg_set_report(struct file *file, struct usb_hidg_report __user *buffer) +{ + struct f_hidg *hidg = file->private_data; + struct f_hidg_req_list *list; + struct usb_request *req; + unsigned long flags; + unsigned short length; + int status; + + spin_lock_irqsave(&hidg->set_spinlock, flags); + +#define SET_REPORT_COND (!list_empty(&hidg->completed_set_req)) + + /* wait for at least one buffer to complete */ + while (!SET_REPORT_COND) { + spin_unlock_irqrestore(&hidg->set_spinlock, flags); + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + if (wait_event_interruptible(hidg->set_queue, SET_REPORT_COND)) + return -ERESTARTSYS; + + spin_lock_irqsave(&hidg->set_spinlock, flags); + } + + /* pick the first one */ + list = list_first_entry(&hidg->completed_set_req, + struct f_hidg_req_list, list); + + /* + * Remove this from list to protect it from being free() + * while host disables our function + */ + list_del(&list->list); + + req = list->req; + spin_unlock_irqrestore(&hidg->set_spinlock, flags); + + /* copy to user outside spinlock */ + length = min_t(unsigned short, sizeof(buffer->data), req->actual); + status = copy_to_user(&buffer->length, &length, sizeof(buffer->length)); + if (!status) { + status = copy_to_user(&buffer->data, req->buf, length); + } + kfree(list); + free_ep_req(hidg->func.config->cdev->gadget->ep0, req); + return status; +} static int f_hidg_get_report(struct file *file, struct usb_hidg_report __user *buffer) { @@ -570,6 +623,8 @@ static int f_hidg_get_report(struct file *file, struct usb_hidg_report __user *b static long f_hidg_ioctl(struct file *file, unsigned int code, unsigned long arg) { switch (code) { + case GADGET_HID_READ_SET_REPORT: + return f_hidg_set_report(file, (struct usb_hidg_report __user *)arg); case GADGET_HID_WRITE_GET_REPORT: return f_hidg_get_report(file, (struct usb_hidg_report __user *)arg); default: @@ -584,6 +639,7 @@ static __poll_t f_hidg_poll(struct file *file, poll_table *wait) poll_wait(file, &hidg->read_queue, wait); poll_wait(file, &hidg->write_queue, wait); + poll_wait(file, &hidg->set_queue, wait); if (WRITE_COND) ret |= EPOLLOUT | EPOLLWRNORM; @@ -596,12 +652,16 @@ static __poll_t f_hidg_poll(struct file *file, poll_table *wait) ret |= EPOLLIN | EPOLLRDNORM; } + if (SET_REPORT_COND) + ret |= EPOLLPRI; + return ret; } #undef WRITE_COND #undef READ_COND_SSREPORT #undef READ_COND_INTOUT +#undef SET_REPORT_COND #undef GET_REPORT_COND static int f_hidg_release(struct inode *inode, struct file *fd) @@ -646,11 +706,19 @@ static void hidg_intout_complete(struct usb_ep *ep, struct usb_request *req) req_list->req = req; - spin_lock_irqsave(&hidg->read_spinlock, flags); - list_add_tail(&req_list->list, &hidg->completed_out_req); - spin_unlock_irqrestore(&hidg->read_spinlock, flags); + if (ep == cdev->gadget->ep0) { + spin_lock_irqsave(&hidg->set_spinlock, flags); + list_add_tail(&req_list->list, &hidg->completed_set_req); + spin_unlock_irqrestore(&hidg->set_spinlock, flags); - wake_up(&hidg->read_queue); + wake_up(&hidg->set_queue); + } else { + spin_lock_irqsave(&hidg->read_spinlock, flags); + list_add_tail(&req_list->list, &hidg->completed_out_req); + spin_unlock_irqrestore(&hidg->read_spinlock, flags); + + wake_up(&hidg->read_queue); + } break; default: ERROR(cdev, "Set report failed %d\n", req->status); @@ -763,12 +831,29 @@ static int hidg_setup(struct usb_function *f, case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 | HID_REQ_SET_REPORT): VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength); - if (hidg->use_out_ep) + if (!hidg->use_out_ep) { + req->complete = hidg_ssreport_complete; + req->context = hidg; + goto respond; + } + if (!length) { goto stall; - req->complete = hidg_ssreport_complete; + } + req = alloc_ep_req(cdev->gadget->ep0, GFP_ATOMIC); + if (!req) { + return -ENOMEM; + } + req->complete = hidg_intout_complete; req->context = hidg; - goto respond; - break; + req->zero = 0; + req->length = length; + status = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); + if (status < 0) { + ERROR(cdev, "usb_ep_queue error on set_report %d\n", status); + free_ep_req(cdev->gadget->ep0, req); + } + + return status; case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 | HID_REQ_SET_PROTOCOL): @@ -868,6 +953,14 @@ static void hidg_disable(struct usb_function *f) spin_unlock_irqrestore(&hidg->read_spinlock, flags); } + spin_lock_irqsave(&hidg->set_spinlock, flags); + list_for_each_entry_safe(list, next, &hidg->completed_set_req, list) { + free_ep_req(f->config->cdev->gadget->ep0, list->req); + list_del(&list->list); + kfree(list); + } + spin_unlock_irqrestore(&hidg->set_spinlock, flags); + spin_lock_irqsave(&hidg->write_spinlock, flags); if (!hidg->write_pending) { free_ep_req(hidg->in_ep, hidg->req); @@ -1098,11 +1191,14 @@ static int hidg_bind(struct usb_configuration *c, struct usb_function *f) hidg->write_pending = 1; hidg->req = NULL; spin_lock_init(&hidg->read_spinlock); + spin_lock_init(&hidg->set_spinlock); spin_lock_init(&hidg->get_spinlock); init_waitqueue_head(&hidg->write_queue); init_waitqueue_head(&hidg->read_queue); + init_waitqueue_head(&hidg->set_queue); init_waitqueue_head(&hidg->get_queue); INIT_LIST_HEAD(&hidg->completed_out_req); + INIT_LIST_HEAD(&hidg->completed_set_req); /* create char device */ cdev_init(&hidg->cdev, &f_hidg_fops); diff --git a/include/uapi/linux/usb/g_hid.h b/include/uapi/linux/usb/g_hid.h index c6068b486354..81416698e145 100644 --- a/include/uapi/linux/usb/g_hid.h +++ b/include/uapi/linux/usb/g_hid.h @@ -33,6 +33,7 @@ struct usb_hidg_report { * Don't add any colliding codes to either driver, and keep * them in unique ranges (size 0x20 for now). */ +#define GADGET_HID_READ_SET_REPORT _IOR('g', 0x41, struct usb_hidg_report) #define GADGET_HID_WRITE_GET_REPORT _IOW('g', 0x42, struct usb_hidg_report) #endif /* __UAPI_LINUX_USB_G_HID_H */