Re: [PATCH 5/6] drm/meson: add DSI encoder

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

Hi Neil,

I love your patch! Perhaps something to improve:

[auto build test WARNING on drm/drm-next]
[also build test WARNING on drm-intel/for-linux-next drm-tip/drm-tip drm-exynos/exynos-drm-next next-20220107]
[cannot apply to tegra-drm/drm/tegra/for-next airlied/drm-next v5.16-rc8]
[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/Neil-Armstrong/drm-meson-add-support-for-MIPI-DSI-Display/20220107-225717
base:   git://anongit.freedesktop.org/drm/drm drm-next
config: arm-randconfig-r002-20220107 (https://download.01.org/0day-ci/archive/20220109/202201090255.SV1mvcAL-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project f3a344d2125fa37e59bae1b0874442c650a19607)
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 arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        # https://github.com/0day-ci/linux/commit/ceb473650c47d3914419f8795fba12fbc9947710
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Neil-Armstrong/drm-meson-add-support-for-MIPI-DSI-Display/20220107-225717
        git checkout ceb473650c47d3914419f8795fba12fbc9947710
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/gpu/drm/meson/

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/gpu/drm/meson/meson_encoder_dsi.c:121:69: warning: variable 'ret' is uninitialized when used here [-Wuninitialized]
                   dev_dbg(priv->dev, "Failed to find DSI transceiver bridge: %d\n", ret);
                                                                                     ^~~
   include/linux/dev_printk.h:155:39: note: expanded from macro 'dev_dbg'
           dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
                                                ^~~~~~~~~~~
   include/linux/dynamic_debug.h:167:19: note: expanded from macro 'dynamic_dev_dbg'
                              dev, fmt, ##__VA_ARGS__)
                                          ^~~~~~~~~~~
   include/linux/dynamic_debug.h:152:56: note: expanded from macro '_dynamic_func_call'
           __dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
                                                                 ^~~~~~~~~~~
   include/linux/dynamic_debug.h:134:15: note: expanded from macro '__dynamic_func_call'
                   func(&id, ##__VA_ARGS__);               \
                               ^~~~~~~~~~~
   drivers/gpu/drm/meson/meson_encoder_dsi.c:106:9: note: initialize the variable 'ret' to silence this warning
           int ret;
                  ^
                   = 0
   1 warning generated.


vim +/ret +121 drivers/gpu/drm/meson/meson_encoder_dsi.c

   101	
   102	int meson_encoder_dsi_init(struct meson_drm *priv)
   103	{
   104		struct meson_encoder_dsi *meson_encoder_dsi;
   105		struct device_node *remote;
   106		int ret;
   107	
   108		meson_encoder_dsi = devm_kzalloc(priv->dev, sizeof(*meson_encoder_dsi), GFP_KERNEL);
   109		if (!meson_encoder_dsi)
   110			return -ENOMEM;
   111	
   112		/* DSI Transceiver Bridge */
   113		remote = of_graph_get_remote_node(priv->dev->of_node, 2, 0);
   114		if (!remote) {
   115			dev_err(priv->dev, "DSI transceiver device is disabled");
   116			return 0;
   117		}
   118	
   119		meson_encoder_dsi->next_bridge = of_drm_find_bridge(remote);
   120		if (!meson_encoder_dsi->next_bridge) {
 > 121			dev_dbg(priv->dev, "Failed to find DSI transceiver bridge: %d\n", ret);

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org