From patchwork Thu Feb 18 07:58:57 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Szyprowski X-Patchwork-Id: 62156 Delivered-To: patch@linaro.org Received: by 10.112.43.199 with SMTP id y7csp442844lbl; Wed, 17 Feb 2016 23:59:11 -0800 (PST) X-Received: by 10.98.9.92 with SMTP id e89mr8190310pfd.34.1455782351011; Wed, 17 Feb 2016 23:59:11 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id q7si7875531pfq.27.2016.02.17.23.59.10; Wed, 17 Feb 2016 23:59:10 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934150AbcBRH7I (ORCPT + 30 others); Thu, 18 Feb 2016 02:59:08 -0500 Received: from mailout1.w1.samsung.com ([210.118.77.11]:35240 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933792AbcBRH7F (ORCPT ); Thu, 18 Feb 2016 02:59:05 -0500 Received: from eucpsbgm2.samsung.com (unknown [203.254.199.245]) by mailout1.w1.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0O2Q00H31GUF7410@mailout1.w1.samsung.com>; Thu, 18 Feb 2016 07:59:03 +0000 (GMT) X-AuditID: cbfec7f5-f79b16d000005389-d5-56c579c69924 Received: from eusync3.samsung.com ( [203.254.199.213]) by eucpsbgm2.samsung.com (EUCPMTA) with SMTP id 75.3D.21385.6C975C65; Thu, 18 Feb 2016 07:59:02 +0000 (GMT) Received: from amdc1339.digital.local ([106.116.147.30]) by eusync3.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTPA id <0O2Q004O6GUAQ080@eusync3.samsung.com>; Thu, 18 Feb 2016 07:59:02 +0000 (GMT) From: Marek Szyprowski To: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Marek Szyprowski , Ruslan Bilovol , Bartlomiej Zolnierkiewicz , Vegard Nossum , Maxime Ripard , Greg Kroah-Hartman , Peter Chen , Felipe Balbi Subject: [PATCH v2 RESEND] usb: gadget: provide interface for legacy gadgets to get UDC name Date: Thu, 18 Feb 2016 08:58:57 +0100 Message-id: <1455782337-4713-1-git-send-email-m.szyprowski@samsung.com> X-Mailer: git-send-email 1.9.2 In-reply-to: <56B7D2C9.5070301@oracle.com> References: <56B7D2C9.5070301@oracle.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrPLMWRmVeSWpSXmKPExsVy+t/xq7rHKo+GGcyaa2axccZ6VotjbU/Y LZoXr2ezuLxrDpvFomWtzBZrj9xlt9i6aS+zxbHZf5ksenaeYLQ427SG1YHL48mmi4we/w73 M3nsnHWX3WPTqk42j/1z17B7fHx6i8Wjb8sqRo/Pm+QCOKK4bFJSczLLUov07RK4Mr5u/MVU 0KlacW5TTAPjS7kuRk4OCQETibfTz7JC2GISF+6tZ+ti5OIQEljKKHFs4xN2CKeJSWJD1yc2 kCo2AUOJrrddQDYHh4iAtUTfwSCQGmaBj0wSHXMnMIHEhQXiJNY16ICUswioSpzasZwRxOYV cJf4cngyO8QyOYn/L1eAlXMKaEnM+OAHEhYS0JTofNbJOIGRdwEjwypG0dTS5ILipPRcI73i xNzi0rx0veT83E2MkGD8uoNx6TGrQ4wCHIxKPLwbXhwJE2JNLCuuzD3EKMHBrCTC+839aJgQ b0piZVVqUX58UWlOavEhRmkOFiVx3pm73ocICaQnlqRmp6YWpBbBZJk4OKUaGNdtbHz4WUJB y/0Y282J9edFlqxaFVb47ZZs5Lz8pUcmqet9sZyx60P4s/6dn37xHb/4bOe3qRn3d6T4zDRf G9VbHXTs1rtkY1G/aQ//KGz+IvdwVs2JFR6Lg6qEDv8USuGX2uPM0vRdYqMXI+vTGNvXGr7r T8evv6QoluSpxXBb88Lu/9tbz7MpsRRnJBpqMRcVJwIAZ71f20ICAAA= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since commit 855ed04a3758b205e84b269f92d26ab36ed8e2f7 ("usb: gadget: udc-core: independent registration of gadgets and gadget drivers") gadget drivers can not assume that UDC drivers are already available on their initialization. This broke the HACK, which was used in gadgetfs driver, to get UDC controller name. This patch removes this hack and replaces it by additional function in the UDC core (which is usefully only for legacy drivers, please don't use it in the new code). Reported-by: Vegard Nossum Signed-off-by: Marek Szyprowski Tested-by: Vegard Nossum --- changelog: v2: - properly report udc gagdet driver name instead of udc device name v1: https://lkml.org/lkml/2016/2/8/176 - initial version --- drivers/usb/gadget/legacy/inode.c | 29 ++--------------------------- drivers/usb/gadget/udc/udc-core.c | 33 +++++++++++++++++++++++++++++++++ include/linux/usb/gadget.h | 1 + 3 files changed, 36 insertions(+), 27 deletions(-) -- 1.9.2 diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c index 7e179f81d05c..7a62a2f7bc18 100644 --- a/drivers/usb/gadget/legacy/inode.c +++ b/drivers/usb/gadget/legacy/inode.c @@ -227,7 +227,7 @@ static void put_ep (struct ep_data *data) * implicitly, starting with the driver name and then endpoint names. */ -static const char *CHIP; +static char CHIP[32]; /*----------------------------------------------------------------------*/ @@ -1697,28 +1697,6 @@ static struct usb_gadget_driver gadgetfs_driver = { }; /*----------------------------------------------------------------------*/ - -static void gadgetfs_nop(struct usb_gadget *arg) { } - -static int gadgetfs_probe(struct usb_gadget *gadget, - struct usb_gadget_driver *driver) -{ - CHIP = gadget->name; - return -EISNAM; -} - -static struct usb_gadget_driver probe_driver = { - .max_speed = USB_SPEED_HIGH, - .bind = gadgetfs_probe, - .unbind = gadgetfs_nop, - .setup = (void *)gadgetfs_nop, - .disconnect = gadgetfs_nop, - .driver = { - .name = "nop", - }, -}; - - /* DEVICE INITIALIZATION * * fd = open ("/dev/gadget/$CHIP", O_RDWR) @@ -1968,10 +1946,7 @@ gadgetfs_fill_super (struct super_block *sb, void *opts, int silent) if (the_device) return -ESRCH; - /* fake probe to determine $CHIP */ - CHIP = NULL; - usb_gadget_probe_driver(&probe_driver); - if (!CHIP) + if (usb_get_gadget_udc_name(CHIP, sizeof(CHIP)) != 0) return -ENODEV; /* superblock */ diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c index fd73a3ea07c2..4bde2e110e44 100644 --- a/drivers/usb/gadget/udc/udc-core.c +++ b/drivers/usb/gadget/udc/udc-core.c @@ -442,6 +442,39 @@ err1: EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release); /** + * usb_get_gadget_udc_name - get the name of the first UDC controller + * @dst_name + * @len + * This functions returns the name of the first UDC controller in the system. + * Please note that this interface is usefull only for legacy drivers which + * assume that there is only one UDC controller in the system and they need to + * get its name before initialization. There is no guarantee that the UDC + * of the returned name will be still available, when gadget driver registers + * itself. + * + * Returns zero on success, negative errno otherwise. + */ +int usb_get_gadget_udc_name(char *dst_name, int len) +{ + struct usb_udc *udc; + int ret = -ENODEV; + + mutex_lock(&udc_lock); + list_for_each_entry(udc, &udc_list, list) { + const char *name = udc->gadget->name; + /* For now we take the first one */ + if (!udc->driver && strlen(name) + 1 <= len) { + strcpy(dst_name, name); + ret = 0; + break; + } + } + mutex_unlock(&udc_lock); + return ret; +} +EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name); + +/** * usb_add_gadget_udc - adds a new gadget to the udc class driver list * @parent: the parent device to this udc. Usually the controller * driver's device. diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h index d82d0068872b..0a8f08302a34 100644 --- a/include/linux/usb/gadget.h +++ b/include/linux/usb/gadget.h @@ -1126,6 +1126,7 @@ extern int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, void (*release)(struct device *dev)); extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget); extern void usb_del_gadget_udc(struct usb_gadget *gadget); +extern int usb_get_gadget_udc_name(char *dst_name, int len); /*-------------------------------------------------------------------------*/