Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757230AbbDPMH7 (ORCPT ); Thu, 16 Apr 2015 08:07:59 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:58299 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753156AbbDPMHu (ORCPT ); Thu, 16 Apr 2015 08:07:50 -0400 Message-ID: <552FA60D.5030707@ti.com> Date: Thu, 16 Apr 2015 15:07:41 +0300 From: Roger Quadros User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Peter Chen CC: , , , , , , , , , Subject: Re: [RFC][PATCH v2 04/13] usb: gadget: add usb_gadget_start/stop() References: <1429008120-5395-1-git-send-email-rogerq@ti.com> <1429008120-5395-5-git-send-email-rogerq@ti.com> <20150416114839.GD3181@shlinux2> In-Reply-To: <20150416114839.GD3181@shlinux2> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4534 Lines: 146 On 16/04/15 14:48, Peter Chen wrote: > On Tue, Apr 14, 2015 at 01:41:51PM +0300, Roger Quadros wrote: >> The OTG state machine needs a mechanism to start and >> stop the gadget controller. Add usb_gadget_start() >> and usb_gadget_stop(). >> >> Signed-off-by: Roger Quadros >> --- >> drivers/usb/gadget/udc/udc-core.c | 74 +++++++++++++++++++++++++++++++++++++++ >> include/linux/usb/gadget.h | 3 ++ >> 2 files changed, 77 insertions(+) >> >> diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c >> index 5a81cb0..3aa5dd5 100644 >> --- a/drivers/usb/gadget/udc/udc-core.c >> +++ b/drivers/usb/gadget/udc/udc-core.c >> @@ -187,6 +187,7 @@ EXPORT_SYMBOL_GPL(usb_gadget_udc_reset); >> */ >> static inline int usb_gadget_udc_start(struct usb_udc *udc) >> { >> + dev_dbg(&udc->dev, "%s\n", __func__); >> return udc->gadget->ops->udc_start(udc->gadget, udc->driver); >> } >> >> @@ -204,10 +205,83 @@ static inline int usb_gadget_udc_start(struct usb_udc *udc) >> */ >> static inline void usb_gadget_udc_stop(struct usb_udc *udc) >> { >> + dev_dbg(&udc->dev, "%s\n", __func__); >> udc->gadget->ops->udc_stop(udc->gadget); >> } >> >> /** >> + * usb_gadget_start - start the usb gadget controller and connect to bus >> + * @gadget: the gadget device to start >> + * >> + * This is external API for use by OTG core. >> + * >> + * Start the usb device controller and connect to bus (enable pull). >> + */ >> +int usb_gadget_start(struct usb_gadget *gadget) >> +{ >> + int ret; >> + struct usb_udc *udc = NULL; >> + >> + dev_dbg(&gadget->dev, "%s\n", __func__); >> + mutex_lock(&udc_lock); >> + list_for_each_entry(udc, &udc_list, list) >> + if (udc->gadget == gadget) >> + goto found; >> + >> + dev_err(gadget->dev.parent, "%s: gadget not registered.\n", >> + __func__); >> + mutex_unlock(&udc_lock); >> + return -EINVAL; >> + >> +found: >> + ret = usb_gadget_udc_start(udc); >> + if (ret) >> + dev_err(&udc->dev, "USB Device Controller didn't start: %d\n", >> + ret); >> + else >> + usb_gadget_connect(udc->gadget); > > OTG FSM manages its pullup/pulldown itself through its fsm->ops->loc_conn That API usb_gadget_udc_start() is used by DRD (dual-role) FSM as well and it doesn't use ops->loc_conn. So i'm wondering how to make this work for both. I could probably remove the pull up control from usb_gadget_start/stop() and move it into the DRD FSM. cheers, -roger > >> + >> + mutex_unlock(&udc_lock); >> + >> + return ret; >> +} >> +EXPORT_SYMBOL_GPL(usb_gadget_start); >> + >> +/** >> + * usb_gadget_stop - disconnect from bus and stop the usb gadget >> + * @gadget: The gadget device we want to stop >> + * >> + * This is external API for use by OTG core. >> + * >> + * Disconnect from the bus (disable pull) and stop the >> + * gadget controller. >> + */ >> +int usb_gadget_stop(struct usb_gadget *gadget) >> +{ >> + struct usb_udc *udc = NULL; >> + >> + dev_dbg(&gadget->dev, "%s\n", __func__); >> + mutex_lock(&udc_lock); >> + list_for_each_entry(udc, &udc_list, list) >> + if (udc->gadget == gadget) >> + goto found; >> + >> + dev_err(gadget->dev.parent, "%s: gadget not registered.\n", >> + __func__); >> + mutex_unlock(&udc_lock); >> + return -EINVAL; >> + >> +found: >> + usb_gadget_disconnect(udc->gadget); >> + udc->driver->disconnect(udc->gadget); >> + usb_gadget_udc_stop(udc); >> + mutex_unlock(&udc_lock); >> + >> + return 0; >> +} >> +EXPORT_SYMBOL_GPL(usb_gadget_stop); >> + >> +/** >> * usb_udc_release - release the usb_udc struct >> * @dev: the dev member within usb_udc >> * >> diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h >> index e2f00fd..7ada7e6 100644 >> --- a/include/linux/usb/gadget.h >> +++ b/include/linux/usb/gadget.h >> @@ -922,6 +922,9 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver); >> */ >> int usb_gadget_unregister_driver(struct usb_gadget_driver *driver); >> >> +int usb_gadget_start(struct usb_gadget *gadget); >> +int usb_gadget_stop(struct usb_gadget *gadget); >> + >> 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); >> -- >> 2.1.0 >> > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/