From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764481AbbA2DoO (ORCPT ); Wed, 28 Jan 2015 22:44:14 -0500 Received: from mail-lb0-f178.google.com ([209.85.217.178]:54798 "EHLO mail-lb0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754967AbbA2BZl (ORCPT ); Wed, 28 Jan 2015 20:25:41 -0500 From: Ruslan Bilovol To: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, balbi@ti.com, gregkh@linuxfoundation.org Cc: andrzej.p@samsung.com Subject: [PATCH 1/2] usb: gadget: udc-core: independent registration of gadgets and gadget drivers Date: Thu, 29 Jan 2015 03:25:33 +0200 Message-Id: <1422494734-9499-2-git-send-email-ruslan.bilovol@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1422494734-9499-1-git-send-email-ruslan.bilovol@gmail.com> References: <1422494734-9499-1-git-send-email-ruslan.bilovol@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: Ruslan Bilovol --- drivers/usb/gadget/udc/udc-core.c | 113 +++++++++++++++++++++++++++++++++++--- 1 file changed, 105 insertions(+), 8 deletions(-) diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c index e31d574..4c9412b 100644 --- a/drivers/usb/gadget/udc/udc-core.c +++ b/drivers/usb/gadget/udc/udc-core.c @@ -43,13 +43,23 @@ struct usb_udc { struct usb_gadget_driver *driver; struct usb_gadget *gadget; struct device dev; + bool bind_by_name; + struct list_head list; +}; + +struct pending_gadget_driver { + struct usb_gadget_driver *driver; + char *udc_name; struct list_head list; }; 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, + bool bind_by_name); /* ------------------------------------------------------------------------- */ #ifdef CONFIG_HAS_DMA @@ -244,6 +254,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, { struct usb_udc *udc; int ret = -ENOMEM; + struct pending_gadget_driver *pending; udc = kzalloc(sizeof(*udc), GFP_KERNEL); if (!udc) @@ -288,6 +299,24 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); + if (!list_empty(&gadget_driver_pending_list)) { + pending = list_first_entry(&gadget_driver_pending_list, + struct pending_gadget_driver, list); + + if (pending->udc_name) { + if (!strcmp(pending->udc_name, dev_name(&udc->dev))) { + udc_bind_to_driver(udc, pending->driver, true); + list_del(&pending->list); + kfree(pending->udc_name); + kfree(pending); + } + } else { + udc_bind_to_driver(udc, pending->driver, false); + list_del(&pending->list); + kfree(pending); + } + } + mutex_unlock(&udc_lock); return 0; @@ -364,10 +393,32 @@ found: dev_vdbg(gadget->dev.parent, "unregistering gadget\n"); list_del(&udc->list); - mutex_unlock(&udc_lock); - if (udc->driver) + if (udc->driver) { + struct pending_gadget_driver *pending; + + pending = kzalloc(sizeof(*pending), GFP_KERNEL); + if (!pending) + goto err; + + if (udc->bind_by_name) { + pending->udc_name = kstrdup(dev_name(&udc->dev), + GFP_KERNEL); + if (!pending->udc_name) { + kfree(pending); + goto err; + } + } + + pending->driver = udc->driver; + list_add_tail(&pending->list, &gadget_driver_pending_list); + + pr_info("udc-core: added [%s] to list of pending drivers\n", + pending->driver->function); +err: usb_gadget_remove_driver(udc); + } + mutex_unlock(&udc_lock); kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE); flush_work(&gadget->work); @@ -378,7 +429,8 @@ EXPORT_SYMBOL_GPL(usb_del_gadget_udc); /* ------------------------------------------------------------------------- */ -static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver) +static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver, + bool bind_by_name) { int ret; @@ -386,6 +438,7 @@ static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *dri driver->function); udc->driver = driver; + udc->bind_by_name = bind_by_name; udc->dev.driver = &driver->driver; udc->gadget->dev.driver = &driver->driver; @@ -423,14 +476,34 @@ int usb_udc_attach_driver(const char *name, struct usb_gadget_driver *driver) break; } if (ret) { - ret = -ENODEV; + struct pending_gadget_driver *pending; + + pending = kzalloc(sizeof(*pending), GFP_KERNEL); + if (!pending) { + ret = -ENOMEM; + goto out; + } + pending->driver = driver; + pending->udc_name = kstrdup(name, GFP_KERNEL); + if (!pending->udc_name) { + kfree(pending); + ret = -ENOMEM; + goto out; + } + + list_add_tail(&pending->list, &gadget_driver_pending_list); + + pr_info("udc-core: couldn't find the [%s] UDC " + "- add [%s] to list of pending drivers\n", + name, driver->function); + ret = 0; goto out; } if (udc->driver) { ret = -EBUSY; goto out; } - ret = udc_bind_to_driver(udc, driver); + ret = udc_bind_to_driver(udc, driver, true); out: mutex_unlock(&udc_lock); return ret; @@ -440,6 +513,7 @@ EXPORT_SYMBOL_GPL(usb_udc_attach_driver); int usb_gadget_probe_driver(struct usb_gadget_driver *driver) { struct usb_udc *udc = NULL; + struct pending_gadget_driver *pending; int ret; if (!driver || !driver->bind || !driver->setup) @@ -452,11 +526,22 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver) goto found; } - pr_debug("couldn't find an available UDC\n"); + pending = kzalloc(sizeof(*pending), GFP_KERNEL); + if (!pending) { + mutex_unlock(&udc_lock); + return -ENOMEM; + } + pending->driver = driver; + list_add_tail(&pending->list, &gadget_driver_pending_list); + + pr_info("udc-core: couldn't find an available UDC " + "- add [%s] to list of pending drivers\n", + driver->function); + mutex_unlock(&udc_lock); - return -ENODEV; + return 0; found: - ret = udc_bind_to_driver(udc, driver); + ret = udc_bind_to_driver(udc, driver, false); mutex_unlock(&udc_lock); return ret; } @@ -465,6 +550,7 @@ EXPORT_SYMBOL_GPL(usb_gadget_probe_driver); int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) { struct usb_udc *udc = NULL; + struct pending_gadget_driver *pending = NULL; int ret = -ENODEV; if (!driver || !driver->unbind) @@ -480,6 +566,17 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) break; } + if (ret) { + list_for_each_entry(pending, &gadget_driver_pending_list, list) + if (pending->driver == driver) { + list_del(&pending->list); + kfree(pending->udc_name); + kfree(pending); + ret = 0; + break; + } + } + mutex_unlock(&udc_lock); return ret; } -- 1.9.1