Re: [PATCH v2 1/2] usb: gadget: udc: core: Invoke usb_gadget_connect only when started

[kernel test robot <lkp@intel.com>]

Hi Badhri,

kernel test robot noticed the following build warnings:

[auto build test WARNING on d629c0e221cd99198b843d8351a0a9bfec6c0423]

url:    https://github.com/intel-lab-lkp/linux/commits/Badhri-Jagan-Sridharan/usb-gadget-udc-core-Prevent-redundant-calls-to-pullup/20230406-142708
base:   d629c0e221cd99198b843d8351a0a9bfec6c0423
patch link:    https://lore.kernel.org/r/20230406062549.2461917-1-badhri%40google.com
patch subject: [PATCH v2 1/2] usb: gadget: udc: core: Invoke usb_gadget_connect only when started
config: s390-allyesconfig (https://download.01.org/0day-ci/archive/20230406/202304061758.Tz5RJDZU-lkp@intel.com/config)
compiler: s390-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/2f12e8b0c9bf3d25df88c73b614c3e8d84bd7338
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Badhri-Jagan-Sridharan/usb-gadget-udc-core-Prevent-redundant-calls-to-pullup/20230406-142708
        git checkout 2f12e8b0c9bf3d25df88c73b614c3e8d84bd7338
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=s390 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash drivers/usb/gadget/udc/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304061758.Tz5RJDZU-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/usb/gadget/udc/core.c:696:5: warning: no previous prototype for 'usb_gadget_connect_locked' [-Wmissing-prototypes]
     696 | int usb_gadget_connect_locked(struct usb_gadget *gadget)
         |     ^~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/usb/gadget/udc/core.c:749:5: warning: no previous prototype for 'usb_gadget_disconnect_locked' [-Wmissing-prototypes]
     749 | int usb_gadget_disconnect_locked(struct usb_gadget *gadget)
         |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~


vim +/usb_gadget_connect_locked +696 drivers/usb/gadget/udc/core.c

   694	
   695	/* Internal version of usb_gadget_connect needs to be called with udc_connect_control_lock held. */
 > 696	int usb_gadget_connect_locked(struct usb_gadget *gadget)
   697	{
   698		int ret = 0;
   699	
   700		if (!gadget->ops->pullup) {
   701			ret = -EOPNOTSUPP;
   702			goto out;
   703		}
   704	
   705		if (gadget->deactivated || !gadget->udc->started) {
   706			/*
   707			 * If gadget is deactivated we only save new state.
   708			 * Gadget will be connected automatically after activation.
   709			 *
   710			 * udc first needs to be started before gadget can be pulled up.
   711			 */
   712			gadget->connected = true;
   713			goto out;
   714		}
   715	
   716		ret = gadget->ops->pullup(gadget, 1);
   717		if (!ret)
   718			gadget->connected = 1;
   719	
   720	out:
   721		trace_usb_gadget_connect(gadget, ret);
   722	
   723		return ret;
   724	}
   725	
   726	/**
   727	 * usb_gadget_connect - software-controlled connect to USB host
   728	 * @gadget:the peripheral being connected
   729	 *
   730	 * Enables the D+ (or potentially D-) pullup.  The host will start
   731	 * enumerating this gadget when the pullup is active and a VBUS session
   732	 * is active (the link is powered).
   733	 *
   734	 * Returns zero on success, else negative errno.
   735	 */
   736	int usb_gadget_connect(struct usb_gadget *gadget)
   737	{
   738		int ret;
   739	
   740		mutex_lock(&gadget->udc->connect_lock);
   741		ret = usb_gadget_connect_locked(gadget);
   742		mutex_unlock(&gadget->udc->connect_lock);
   743	
   744		return ret;
   745	}
   746	EXPORT_SYMBOL_GPL(usb_gadget_connect);
   747	
   748	/* Internal version of usb_gadget_disconnect needs to be called with udc->connect_lock held. */
 > 749	int usb_gadget_disconnect_locked(struct usb_gadget *gadget)
   750	{
   751		int ret = 0;
   752	
   753		if (!gadget->ops->pullup) {
   754			ret = -EOPNOTSUPP;
   755			goto out;
   756		}
   757	
   758		if (!gadget->connected)
   759			goto out;
   760	
   761		if (gadget->deactivated || !gadget->udc->started) {
   762			/*
   763			 * If gadget is deactivated we only save new state.
   764			 * Gadget will stay disconnected after activation.
   765			 *
   766			 * udc should have been started before gadget being pulled down.
   767			 */
   768			gadget->connected = false;
   769			goto out;
   770		}
   771	
   772		ret = gadget->ops->pullup(gadget, 0);
   773		if (!ret)
   774			gadget->connected = 0;
   775	
   776		mutex_lock(&udc_lock);
   777		if (gadget->udc->driver)
   778			gadget->udc->driver->disconnect(gadget);
   779		mutex_unlock(&udc_lock);
   780	
   781	out:
   782		trace_usb_gadget_disconnect(gadget, ret);
   783	
   784		return ret;
   785	}
   786	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests