[PATCH] ASoC: mediatek: common: Switch to for_each_available_child_of_node_scoped()

[kernel test robot]

Hi Chen-Yu,

kernel test robot noticed the following build warnings:

[auto build test WARNING on broonie-sound/for-next]
[also build test WARNING on broonie-spi/for-next linus/master v6.17-rc2 next-20250822]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Chen-Yu-Tsai/ASoC-mediatek-common-Switch-to-for_each_available_child_of_node_scoped/20250822-142918
base:   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next
patch link:    https://lore.kernel.org/r/20250822062738.2632746-1-wenst%40chromium.org
patch subject: [PATCH] ASoC: mediatek: common: Switch to for_each_available_child_of_node_scoped()
config: x86_64-buildonly-randconfig-001-20250823 (https://download.01.org/0day-ci/archive/20250823/202508230528.DeD3hVns-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14+deb12u1) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250823/202508230528.DeD3hVns-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp at intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202508230528.DeD3hVns-lkp@intel.com/

All warnings (new ones prefixed by >>):

   sound/soc/mediatek/common/mtk-soundcard-driver.c: In function 'parse_dai_link_info':
>> sound/soc/mediatek/common/mtk-soundcard-driver.c:92:29: warning: unused variable 'sub_node' [-Wunused-variable]
      92 |         struct device_node *sub_node;
         |                             ^~~~~~~~


vim +/sub_node +92 sound/soc/mediatek/common/mtk-soundcard-driver.c

c0e7390e6d3f42b Trevor Wu    2023-05-26   88  
4302187d955f166 Trevor Wu    2023-01-16   89  int parse_dai_link_info(struct snd_soc_card *card)
4302187d955f166 Trevor Wu    2023-01-16   90  {
4302187d955f166 Trevor Wu    2023-01-16   91  	struct device *dev = card->dev;
4302187d955f166 Trevor Wu    2023-01-16  @92  	struct device_node *sub_node;
4302187d955f166 Trevor Wu    2023-01-16   93  	struct snd_soc_dai_link *dai_link;
4302187d955f166 Trevor Wu    2023-01-16   94  	const char *dai_link_name;
4302187d955f166 Trevor Wu    2023-01-16   95  	int ret, i;
4302187d955f166 Trevor Wu    2023-01-16   96  
4302187d955f166 Trevor Wu    2023-01-16   97  	/* Loop over all the dai link sub nodes */
bd1311e421261f6 Chen-Yu Tsai 2025-08-22   98  	for_each_available_child_of_node_scoped(dev->of_node, sub_node) {
4302187d955f166 Trevor Wu    2023-01-16   99  		if (of_property_read_string(sub_node, "link-name",
bd1311e421261f6 Chen-Yu Tsai 2025-08-22  100  					    &dai_link_name))
4302187d955f166 Trevor Wu    2023-01-16  101  			return -EINVAL;
4302187d955f166 Trevor Wu    2023-01-16  102  
4302187d955f166 Trevor Wu    2023-01-16  103  		for_each_card_prelinks(card, i, dai_link) {
4302187d955f166 Trevor Wu    2023-01-16  104  			if (!strcmp(dai_link_name, dai_link->name))
4302187d955f166 Trevor Wu    2023-01-16  105  				break;
4302187d955f166 Trevor Wu    2023-01-16  106  		}
4302187d955f166 Trevor Wu    2023-01-16  107  
bd1311e421261f6 Chen-Yu Tsai 2025-08-22  108  		if (i >= card->num_links)
4302187d955f166 Trevor Wu    2023-01-16  109  			return -EINVAL;
4302187d955f166 Trevor Wu    2023-01-16  110  
4302187d955f166 Trevor Wu    2023-01-16  111  		ret = set_card_codec_info(card, sub_node, dai_link);
bd1311e421261f6 Chen-Yu Tsai 2025-08-22  112  		if (ret < 0)
4302187d955f166 Trevor Wu    2023-01-16  113  			return ret;
c0e7390e6d3f42b Trevor Wu    2023-05-26  114  
c0e7390e6d3f42b Trevor Wu    2023-05-26  115  		ret = set_dailink_daifmt(card, sub_node, dai_link);
bd1311e421261f6 Chen-Yu Tsai 2025-08-22  116  		if (ret < 0)
c0e7390e6d3f42b Trevor Wu    2023-05-26  117  			return ret;
c0e7390e6d3f42b Trevor Wu    2023-05-26  118  	}
4302187d955f166 Trevor Wu    2023-01-16  119  
4302187d955f166 Trevor Wu    2023-01-16  120  	return 0;
4302187d955f166 Trevor Wu    2023-01-16  121  }
4302187d955f166 Trevor Wu    2023-01-16  122  EXPORT_SYMBOL_GPL(parse_dai_link_info);
4302187d955f166 Trevor Wu    2023-01-16  123  

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