Hi Maximilian,

I love your patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v5.13-rc4 next-20210603]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Maximilian-Luz/platform-surface-aggregator-Extend-user-space-interface-for-events/20210604-074904
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f88cd3fb9df228e5ce4e13ec3dbad671ddb2146e
config: x86_64-randconfig-r016-20210604 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 5c0d1b2f902aa6a9cf47cc7e42c5b83bb2217cf9)
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
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/7b6b5a24e7c8e389e231ee547972e871145f5972
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Maximilian-Luz/platform-surface-aggregator-Extend-user-space-interface-for-events/20210604-074904
        git checkout 7b6b5a24e7c8e389e231ee547972e871145f5972
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/platform/surface/aggregator/controller.c:2317:23: warning: variable 'nf_head' set but not used [-Wunused-but-set-variable]
           struct ssam_nf_head *nf_head;
                                ^
   drivers/platform/surface/aggregator/controller.c:2386:23: warning: variable 'nf_head' set but not used [-Wunused-but-set-variable]
           struct ssam_nf_head *nf_head;
                                ^
   2 warnings generated.


vim +/nf_head +2317 drivers/platform/surface/aggregator/controller.c

  2289	
  2290	/**
  2291	 * ssam_controller_event_enable() - Enable the specified event.
  2292	 * @ctrl:  The controller to enable the event for.
  2293	 * @reg:   The event registry to use for enabling the event.
  2294	 * @id:    The event ID specifying the event to be enabled.
  2295	 * @flags: The SAM event flags used for enabling the event.
  2296	 *
  2297	 * Increment the event reference count of the specified event. If the event has
  2298	 * not been enabled previously, it will be enabled by this call.
  2299	 *
  2300	 * Note: In general, ssam_notifier_register() with a non-observer notifier
  2301	 * should be preferred for enabling/disabling events, as this will guarantee
  2302	 * proper ordering and event forwarding in case of errors during event
  2303	 * enabling/disabling.
  2304	 *
  2305	 * Return: Returns zero on success, %-ENOSPC if the reference count for the
  2306	 * specified event has reached its maximum, %-ENOMEM if the corresponding event
  2307	 * entry could not be allocated. If this is the first time that this event has
  2308	 * been enabled (i.e. the reference count was incremented from zero to one by
  2309	 * this call), returns the status of the event-enable EC-command.
  2310	 */
  2311	int ssam_controller_event_enable(struct ssam_controller *ctrl,
  2312					 struct ssam_event_registry reg,
  2313					 struct ssam_event_id id, u8 flags)
  2314	{
  2315		u16 rqid = ssh_tc_to_rqid(id.target_category);
  2316		struct ssam_nf_refcount_entry *entry;
> 2317		struct ssam_nf_head *nf_head;
  2318		struct ssam_nf *nf;
  2319		int status;
  2320	
  2321		if (!ssh_rqid_is_event(rqid))
  2322			return -EINVAL;
  2323	
  2324		nf = &ctrl->cplt.event.notif;
  2325		nf_head = &nf->head[ssh_rqid_to_event(rqid)];
  2326	
  2327		mutex_lock(&nf->lock);
  2328	
  2329		entry = ssam_nf_refcount_inc(nf, reg, id);
  2330		if (IS_ERR(entry)) {
  2331			mutex_unlock(&nf->lock);
  2332			return PTR_ERR(entry);
  2333		}
  2334	
  2335		ssam_dbg(ctrl, "enabling event (reg: %#04x, tc: %#04x, iid: %#04x, rc: %d)\n",
  2336			 reg.target_category, id.target_category, id.instance,
  2337			 entry->refcount);
  2338	
  2339		if (entry->refcount == 1) {
  2340			status = ssam_ssh_event_enable(ctrl, reg, id, flags);
  2341			if (status) {
  2342				kfree(ssam_nf_refcount_dec(nf, reg, id));
  2343				mutex_unlock(&nf->lock);
  2344				return status;
  2345			}
  2346	
  2347			entry->flags = flags;
  2348	
  2349		} else if (entry->flags != flags) {
  2350			ssam_warn(ctrl,
  2351				  "inconsistent flags when enabling event: got %#04x, expected %#04x (reg: %#04x, tc: %#04x, iid: %#04x)\n",
  2352				  flags, entry->flags, reg.target_category,
  2353				  id.target_category, id.instance);
  2354		}
  2355	
  2356		mutex_unlock(&nf->lock);
  2357		return 0;
  2358	}
  2359	EXPORT_SYMBOL_GPL(ssam_controller_event_enable);
  2360	

---
0-DAY CI Kernel Test Service, Intel Corporation
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