Re: [linux-next:master 3918/4407] drivers/hwmon/sbrmi.c:211:7: warning: variable 'ret' is used uninitialized whenever switch case is taken

Re: [linux-next:master 3918/4407] drivers/hwmon/sbrmi.c:211:7: warning: variable 'ret' is used uninitialized whenever switch case is taken

[Guenter Roeck]

On 7/30/21 6:03 AM, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   4ccc9e2db7ac33f450a1ff6ce158a71e5a81ded9
> commit: 4f5b70eb322a2ab7efc7a60a572fa72e46c89f16 [3918/4407] hwmon: Add support for SB-RMI power module
> config: x86_64-buildonly-randconfig-r002-20210730 (attached as .config)
> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 4f71f59bf3d9914188a11d0c41bedbb339d36ff5)
> 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://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=4f5b70eb322a2ab7efc7a60a572fa72e46c89f16
>          git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>          git fetch --no-tags linux-next master
>          git checkout 4f5b70eb322a2ab7efc7a60a572fa72e46c89f16
>          # 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/hwmon/sbrmi.c:211:7: warning: variable 'ret' is used uninitialized whenever switch case is taken [-Wsometimes-uninitialized]
>             case hwmon_power_cap_max:
>                  ^~~~~~~~~~~~~~~~~~~
>     drivers/hwmon/sbrmi.c:217:6: note: uninitialized use occurs here
>             if (ret < 0)
>                 ^~~
>     drivers/hwmon/sbrmi.c:196:9: note: initialize the variable 'ret' to silence this warning
>             int ret;
>                    ^
>                     = 0
>     1 warning generated.
> 

There is no need to send an updated patch; I fixed this up.

Thanks,
Guenter

> 
> vim +/ret +211 drivers/hwmon/sbrmi.c
> 
>     190	
>     191	static int sbrmi_read(struct device *dev, enum hwmon_sensor_types type,
>     192			      u32 attr, int channel, long *val)
>     193	{
>     194		struct sbrmi_data *data = dev_get_drvdata(dev);
>     195		struct sbrmi_mailbox_msg msg = { 0 };
>     196		int ret;
>     197	
>     198		if (type != hwmon_power)
>     199			return -EINVAL;
>     200	
>     201		msg.read = true;
>     202		switch (attr) {
>     203		case hwmon_power_input:
>     204			msg.cmd = SBRMI_READ_PKG_PWR_CONSUMPTION;
>     205			ret = rmi_mailbox_xfer(data, &msg);
>     206			break;
>     207		case hwmon_power_cap:
>     208			msg.cmd = SBRMI_READ_PKG_PWR_LIMIT;
>     209			ret = rmi_mailbox_xfer(data, &msg);
>     210			break;
>   > 211		case hwmon_power_cap_max:
>     212			msg.data_out = data->pwr_limit_max;
>     213			break;
>     214		default:
>     215			return -EINVAL;
>     216		}
>     217		if (ret < 0)
>     218			return ret;
>     219		/* hwmon power attributes are in microWatt */
>     220		*val = (long)msg.data_out * 1000;
>     221		return ret;
>     222	}
>     223	
> 
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
>