Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754819AbcCWMVw (ORCPT ); Wed, 23 Mar 2016 08:21:52 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:41384 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751765AbcCWMVr (ORCPT ); Wed, 23 Mar 2016 08:21:47 -0400 Date: Wed, 23 Mar 2016 13:21:43 +0100 From: Pavel Machek To: Marek Szyprowski Cc: Ruslan Bilovol , pali.rohar@gmail.com, sre@kernel.org, kernel list , linux-arm-kernel , linux-omap , Tony Lindgren , khilman@kernel.org, aaro.koskinen@iki.fi, ivo.g.dimitrov.75@gmail.com, patrikbachan@gmail.com, serge@hallyn.com, Maxime Ripard , Peter Chen , Felipe Balbi Subject: Re: usb: gadget breakage on N900: bind UDC by name passed via usb_gadget_driver structure Message-ID: <20160323122143.GB32031@amd> References: <20160317212603.GA16651@amd> <20160318202041.GA20196@amd> <56EFE057.7070106@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <56EFE057.7070106@samsung.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6924 Lines: 197 On Mon 2016-03-21 12:51:51, Marek Szyprowski wrote: > Hi > > On 2016-03-18 21:20, Pavel Machek wrote: > >Hi! > > > >>>USB gadget stops working for me on n900, if I merge > >>Could you please give us more details? > >>Which gadget driver do you use (g_nokia?) > >Ok, so I could get it to work with v4.5, and this patch. I'm including > >my config, too. No, I don't think I'm using g_nokia. > > This shows that there are some serious problems, probably with your udc > driver, which doesn't handle deferred probe properly. Your patch workaround > it by waiting some predefined time before registering gadget driver, however > this is not the proper way. Please try to isolate what exactly is needed to > get the gadget driver registered properly in your system or at least please > provide some logs from the failed case. Well, Ruslan said he has n900 available, so I provided requested information. This is the dmesg with the hack: [ 0.623138] of_get_named_gpiod_flags: parsed 'ti,power-gpio' property of node '/ocp/spi@480ba00 0/wl1251@0[0]' - status (0) [ 0.623565] wl1251: ERROR vio regulator missing: -517 [ 0.624359] musb probe HACK cf9a9e00 [ 0.624420] musb probe HACK/2 cf9a9e00 [ 0.624511] musb probe HACK/3 cf9a9e00 [ 0.624755] HS USB OTG: no transceiver configured [ 0.624847] musb-hdrc musb-hdrc.0.auto: musb_init_controller failed with status -517 [ 0.626525] mousedev: PS/2 mouse device common for all mice ... [ 2.877441] ieee80211 phy1: Selected rate control algorithm 'minstrel' [ 2.879882] wl1251: loaded [ 2.889617] wl1251: initialized [ 2.897521] Two musb controllers? HACK [ 2.904968] musb probe HACK cf9a9e00 [ 2.912048] musb probe HACK/2 cf9a9e00 [ 2.918823] musb probe HACK/3 cf9a9e00 [ 2.928985] musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, bulk combine, bulk split, HB-ISO Rx, HB-ISO Tx, SoftConn) [ 2.929016] musb-hdrc: MHDRC RTL version 1.400 [ 2.929046] musb-hdrc: setup fifo_mode 4 [ 2.929077] musb-hdrc: 28/31 max ep, 16384/16384 memory [ 2.930511] tsc2005 spi1.0: GPIO lookup for consumer reset [ 2.930541] tsc2005 spi1.0: using device tree for GPIO lookup In the kernel without the hack, there'll be only the first part of the dmesg, AFAICT. If there's an interest, I can repeat the test without the hack. Thanks, Pavel > >diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c > >index b86a6f0..bee109f 100644 > >--- a/drivers/usb/gadget/udc/udc-core.c > >+++ b/drivers/usb/gadget/udc/udc-core.c > >@@ -542,14 +542,37 @@ err1: > > return ret; > > } > >-int usb_gadget_probe_driver(struct usb_gadget_driver *driver) > >+int usb_udc_attach_driver(const char *name, struct usb_gadget_driver *driver) > >+{ > >+ struct usb_udc *udc = NULL; > >+ int ret = -ENODEV; > >+ > >+ mutex_lock(&udc_lock); > >+ list_for_each_entry(udc, &udc_list, list) { > >+ ret = strcmp(name, dev_name(&udc->dev)); > >+ if (!ret) > >+ break; > >+ } > >+ if (ret) { > >+ ret = -ENODEV; > >+ goto out; > >+ } > >+ if (udc->driver) { > >+ ret = -EBUSY; > >+ goto out; > >+ } > >+ ret = udc_bind_to_driver(udc, driver); > >+out: > >+ mutex_unlock(&udc_lock); > >+ return ret; > >+} > >+EXPORT_SYMBOL_GPL(usb_udc_attach_driver); > >+ > >+int __usb_gadget_probe_driver(struct usb_gadget_driver *driver) > > { > > struct usb_udc *udc = NULL; > > int ret = -ENODEV; > >- if (!driver || !driver->bind || !driver->setup) > >- return -EINVAL; > >- > > mutex_lock(&udc_lock); > > if (driver->udc_name) { > > list_for_each_entry(udc, &udc_list, list) { > >@@ -567,16 +590,47 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver) > > } > > } > >- list_add_tail(&driver->pending, &gadget_driver_pending_list); > >+// list_add_tail(&driver->pending, &gadget_driver_pending_list); FIXME > > 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 0; > >+ return ret; > > found: > > ret = udc_bind_to_driver(udc, driver); > > mutex_unlock(&udc_lock); > > return ret; > > } > >+ > >+#define USB_GADGET_BIND_RETRIES 5 > >+#define USB_GADGET_BIND_TIMEOUT (3 * HZ) > >+static void usb_gadget_work(struct work_struct *work) > >+{ > >+ struct usb_gadget_driver *driver = container_of(work, > >+ struct usb_gadget_driver, > >+ work.work); > >+ int res; > >+ > >+ if (driver->retries++ > USB_GADGET_BIND_RETRIES) { > >+ pr_err("couldn't find an available UDC\n"); > >+ return; > >+ } > >+ > >+ res = __usb_gadget_probe_driver(driver); > >+ if (res == -ENODEV) > >+ schedule_delayed_work(&driver->work, USB_GADGET_BIND_TIMEOUT); > >+} > >+ > >+int usb_gadget_probe_driver(struct usb_gadget_driver *driver) > >+{ > >+ if (!driver || !driver->bind || !driver->setup) > >+ return -EINVAL; > >+ > >+ INIT_DELAYED_WORK(&driver->work, usb_gadget_work); > >+ schedule_delayed_work(&driver->work, 0); > >+ > >+ return 0; > >+} > > EXPORT_SYMBOL_GPL(usb_gadget_probe_driver); > > int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) > >@@ -587,6 +641,8 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) > > if (!driver || !driver->unbind) > > return -EINVAL; > >+ cancel_delayed_work(&driver->work); > >+ > > mutex_lock(&udc_lock); > > list_for_each_entry(udc, &udc_list, list) > > if (udc->driver == driver) { > >@@ -747,7 +803,7 @@ static int __init usb_udc_init(void) > > udc_class->dev_uevent = usb_udc_uevent; > > return 0; > > } > >-subsys_initcall(usb_udc_init); > >+late_initcall_sync(usb_udc_init); > > static void __exit usb_udc_exit(void) > > { > >diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h > >index d82d006..adb1e68 100644 > >--- a/include/linux/usb/gadget.h > >+++ b/include/linux/usb/gadget.h > >@@ -1014,6 +1014,8 @@ static inline int usb_gadget_activate(struct usb_gadget *gadget) > > * @resume: Invoked on USB resume. May be called in_interrupt. > > * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers > > * and should be called in_interrupt. > >+ * @work: Gadget work used to bind to the USB controller. > >+ * @retries: Gadget retries to bind to the USB controller. > > * @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. > >@@ -1075,6 +1077,8 @@ struct usb_gadget_driver { > > void (*suspend)(struct usb_gadget *); > > void (*resume)(struct usb_gadget *); > > void (*reset)(struct usb_gadget *); > >+ struct delayed_work work; > >+ int retries; > > /* FIXME support safe rmmod */ > > struct device_driver driver; > > > > Best regards -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html