From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162362AbbKTIzk (ORCPT ); Fri, 20 Nov 2015 03:55:40 -0500 Received: from mailout2.w1.samsung.com ([210.118.77.12]:12388 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934867AbbKTIyX (ORCPT ); Fri, 20 Nov 2015 03:54:23 -0500 X-AuditID: cbfec7f4-f79026d00000418a-05-564edfbb6352 From: Marek Szyprowski To: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Marek Szyprowski , Ruslan Bilovol , Bartlomiej Zolnierkiewicz Subject: [PATCH v6 4/4] usb: gadget: udc-core: independent registration of gadgets and gadget drivers Date: Fri, 20 Nov 2015 09:54:12 +0100 Message-id: <1448009652-14716-5-git-send-email-m.szyprowski@samsung.com> X-Mailer: git-send-email 1.9.2 In-reply-to: <1448009652-14716-1-git-send-email-m.szyprowski@samsung.com> References: <1448009652-14716-1-git-send-email-m.szyprowski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrHJMWRmVeSWpSXmKPExsVy+t/xq7p77vuFGZznttg4Yz2rxeVdc9gs Fi1rZbZYe+Quu0XPzhOMDqweO2fdZffo27KK0ePzJrkA5igum5TUnMyy1CJ9uwSujNUrD7IW LFOv6Nl9ga2BcYZCFyMnh4SAicSlqx+ZIWwxiQv31rN1MXJxCAksZZTY0/eJFcJpYpJo6NjN BFLFJmAo0fW2C6iKg0NEwFqi72AQSA2zwBRGiZ+3n4HVCAukS3z42MgCYrMIqEpM/LCUEaSe V8BD4uZCDohlchL/X64AK+cU8JSYPf0yO4gtBFTy89RJ5gmMvAsYGVYxiqaWJhcUJ6XnGuoV J+YWl+al6yXn525ihITKlx2Mi49ZHWIU4GBU4uFtEPcLE2JNLCuuzD3EKMHBrCTCu9QPKMSb klhZlVqUH19UmpNafIhRmoNFSZx37q73IUIC6YklqdmpqQWpRTBZJg5OqQZGK/8dQGusdrq8 3K5w3Cxw8v1jl9eFvzE/I/A9uuhhXvubPvEpmjYu8ha3V37h8zfKOzq78OEibulpG7c88H7B 37PJwsLsuen7FyEvYp7O8eae0/aPQ25p82Pm0ufP5QQLXxSVJRvZeDywY1nOzzxbSFPk+7ks /eraww1J3hNuFbZFHWebvlmJpTgj0VCLuag4EQBWl6bhEQIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ruslan Bilovol Change behavior during registration of gadgets and gadget drivers in udc-core. Instead of previous approach when for successful probe of usb gadget driver at least one usb gadget should be already registered use another one where gadget drivers and gadgets can be registered in udc-core independently. Independent registration of gadgets and gadget drivers is useful for built-in into kernel gadget and gadget driver case - because it's possible that gadget is really probed only on late_init stage (due to deferred probe) whereas gadget driver's probe is silently failed on module_init stage due to no any UDC added. Also it is useful for modules case - now there is no difference what module to insert first: gadget module or gadget driver one. Tested-by: Maxime Ripard Signed-off-by: Ruslan Bilovol [simplified code as requested by Alan Stern and Felipe Balbi] Signed-off-by: Marek Szyprowski --- drivers/usb/gadget/udc/udc-core.c | 43 +++++++++++++++++++++++++++++++-------- include/linux/usb/gadget.h | 2 ++ 2 files changed, 37 insertions(+), 8 deletions(-) diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c index f76ebc8..461b311 100644 --- a/drivers/usb/gadget/udc/udc-core.c +++ b/drivers/usb/gadget/udc/udc-core.c @@ -51,8 +51,12 @@ struct usb_udc { static struct class *udc_class; static LIST_HEAD(udc_list); +static LIST_HEAD(gadget_driver_pending_list); static DEFINE_MUTEX(udc_lock); +static int udc_bind_to_driver(struct usb_udc *udc, + struct usb_gadget_driver *driver); + /* ------------------------------------------------------------------------- */ #ifdef CONFIG_HAS_DMA @@ -356,6 +360,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, void (*release)(struct device *dev)) { struct usb_udc *udc; + struct usb_gadget_driver *driver; int ret = -ENOMEM; udc = kzalloc(sizeof(*udc), GFP_KERNEL); @@ -403,6 +408,18 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); udc->vbus = true; + /* pick up one of pending gadget drivers */ + list_for_each_entry(driver, &gadget_driver_pending_list, pending) { + if (!driver->udc_name || strcmp(driver->udc_name, + dev_name(&udc->dev)) == 0) { + ret = udc_bind_to_driver(udc, driver); + if (ret) + goto err4; + list_del(&driver->pending); + break; + } + } + mutex_unlock(&udc_lock); return 0; @@ -475,9 +492,16 @@ void usb_del_gadget_udc(struct usb_gadget *gadget) list_del(&udc->list); mutex_unlock(&udc_lock); - if (udc->driver) + if (udc->driver) { + struct usb_gadget_driver *driver = udc->driver; + usb_gadget_remove_driver(udc); + mutex_lock(&udc_lock); + list_add(&driver->pending, &gadget_driver_pending_list); + mutex_unlock(&udc_lock); + } + kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE); flush_work(&gadget->work); device_unregister(&udc->dev); @@ -535,11 +559,7 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver) if (!ret) break; } - if (ret) - ret = -ENODEV; - else if (udc->driver) - ret = -EBUSY; - else + if (!ret && !udc->driver) goto found; } else { list_for_each_entry(udc, &udc_list, list) { @@ -549,9 +569,12 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver) } } - pr_debug("couldn't find an available UDC\n"); + list_add_tail(&driver->pending, &gadget_driver_pending_list); + pr_info("udc-core: couldn't find an available UDC " + "- added [%s] to list of pending drivers\n", + driver->function); mutex_unlock(&udc_lock); - return ret; + return 0; found: ret = udc_bind_to_driver(udc, driver); mutex_unlock(&udc_lock); @@ -577,6 +600,10 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) break; } + if (ret) { + list_del(&driver->pending); + ret = 0; + } mutex_unlock(&udc_lock); return ret; } diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h index e11f5a2..a3436bf 100644 --- a/include/linux/usb/gadget.h +++ b/include/linux/usb/gadget.h @@ -1014,6 +1014,7 @@ static inline int usb_gadget_activate(struct usb_gadget *gadget) * @driver: Driver model state for this driver. * @udc_name: A name of UDC this driver should be bound to. If udc_name is NULL, * this driver will be bound to any available UDC. + * @pending: UDC core private data used for deferred probe of this driver. * * Devices are disabled till a gadget driver successfully bind()s, which * means the driver will handle setup() requests needed to enumerate (and @@ -1076,6 +1077,7 @@ struct usb_gadget_driver { struct device_driver driver; char *udc_name; + struct list_head pending; }; -- 1.9.2