Hi Andrew,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on sound/for-next]
[also build test ERROR on v5.4-rc6 next-20191105]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Andrew-Gabbasov/ALSA-aloop-Support-sound-timer-as-clock-source-instead-of-jiffies/20191106-073459
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git for-next
config: sh-allmodconfig (attached as .config)
compiler: sh4-linux-gcc (GCC) 7.4.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=7.4.0 make.cross ARCH=sh 

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

All errors (new ones prefixed by >>):

   sound/drivers/aloop.c: In function 'loopback_parse_timer_id':
>> sound/drivers/aloop.c:1063:8: error: 'snd_cards' undeclared (first use in this function); did you mean 'snd_card'?
       if (snd_cards[card] &&
           ^~~~~~~~~
           snd_card
   sound/drivers/aloop.c:1063:8: note: each undeclared identifier is reported only once for each function it appears in

vim +1063 sound/drivers/aloop.c

  1039	
  1040	static int loopback_parse_timer_id(const char * const str,
  1041					   struct snd_timer_id *tid)
  1042	{
  1043		/* [<pref>:](<card name>|<card idx>)[{.,}<dev idx>[{.,}<subdev idx>]] */
  1044		const char * const sep_dev = ".,";
  1045		const char * const sep_pref = ":";
  1046		const char *name = str;
  1047		char save, *sep;
  1048		int card = 0, device = 0, subdevice = 0;
  1049		int err;
  1050	
  1051		sep = strpbrk(str, sep_pref);
  1052		if (sep)
  1053			name = sep + 1;
  1054		sep = strpbrk(name, sep_dev);
  1055		if (sep) {
  1056			save = *sep;
  1057			*sep = '\0';
  1058		}
  1059		err = kstrtoint(name, 0, &card);
  1060		if (err == -EINVAL) {
  1061			/* Must be the name, not number */
  1062			for (card = 0; card < snd_ecards_limit; card++) {
> 1063				if (snd_cards[card] &&
  1064				    !strcmp(snd_cards[card]->id, name)) {
  1065					err = 0;
  1066					break;
  1067				}
  1068			}
  1069		}
  1070		if (!err && sep) {
  1071			char save2, *sep2;
  1072			sep2 = strpbrk(sep + 1, sep_dev);
  1073			if (sep2) {
  1074				save2 = *sep2;
  1075				*sep2 = '\0';
  1076			}
  1077			err = kstrtoint(sep + 1, 0, &device);
  1078			if (!err && sep2) {
  1079				err = kstrtoint(sep2 + 1, 0, &subdevice);
  1080			}
  1081			if (sep2)
  1082				*sep2 = save2;
  1083		}
  1084		if (!err && tid) {
  1085			tid->card = card;
  1086			tid->device = device;
  1087			tid->subdevice = subdevice;
  1088		}
  1089		if (sep)
  1090			*sep = save;
  1091		return err;
  1092	}
  1093	

---
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