From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Chen Subject: Re: [PATCH v2 08/22] usb: chipidea: Remove locking in ci_udc_start() Date: Fri, 8 Jul 2016 17:45:28 +0800 Message-ID: <20160708094528.GF20485@shlinux2> References: <20160707222114.1673-1-stephen.boyd@linaro.org> <20160707222114.1673-9-stephen.boyd@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20160707222114.1673-9-stephen.boyd-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stephen Boyd Cc: linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Felipe Balbi , Arnd Bergmann , Neil Armstrong , linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Bjorn Andersson , Peter Chen , Greg Kroah-Hartman , Andy Gross , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-arm-msm@vger.kernel.org On Thu, Jul 07, 2016 at 03:20:59PM -0700, Stephen Boyd wrote: > We don't call hw_device_reset() with the ci->lock held, so it > doesn't seem like this lock here is protecting anything. Let's > just remove it. This allows us to call sleeping functions like > phy_init() from within the CI_HDRC_CONTROLLER_RESET_EVENT hook. > > Cc: Peter Chen > Cc: Greg Kroah-Hartman > Signed-off-by: Stephen Boyd > --- > drivers/usb/chipidea/udc.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c > index 065f5d97aa67..f16be4710cdb 100644 > --- a/drivers/usb/chipidea/udc.c > +++ b/drivers/usb/chipidea/udc.c > @@ -1719,7 +1719,6 @@ static int ci_udc_start(struct usb_gadget *gadget, > struct usb_gadget_driver *driver) > { > struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget); > - unsigned long flags; > int retval = -ENOMEM; > > if (driver->disconnect == NULL) > @@ -1746,7 +1745,6 @@ static int ci_udc_start(struct usb_gadget *gadget, > > pm_runtime_get_sync(&ci->gadget.dev); > if (ci->vbus_active) { > - spin_lock_irqsave(&ci->lock, flags); > hw_device_reset(ci); > } else { > usb_udc_vbus_handler(&ci->gadget, false); > @@ -1755,7 +1753,6 @@ static int ci_udc_start(struct usb_gadget *gadget, > } > > retval = hw_device_state(ci, ci->ep0out->qh.dma); > - spin_unlock_irqrestore(&ci->lock, flags); > if (retval) > pm_runtime_put_sync(&ci->gadget.dev); > The main purpose for this is disabling interrupt when reset controller, in case the unexpected interrupts occur. You can move this between hw_device_state. -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html