drivers/hwmon/nct7802.c:714 nct7802_temp_is_visible() warn: compare has higher precedence than mask

From: Dan Carpenter
Date: Tue Sep 28 2021 - 10:52:01 EST

tree: https://github.com/0day-ci/linux/commits/Oskar-Senft/dt-bindings-hwmon-Add-nct7802-bindings/20210922-121927
head: 0654ba359c66a776f243b53f407f200f9e53a9ba
commit: 0654ba359c66a776f243b53f407f200f9e53a9ba hwmon: (nct7802) Make temperature sensors configurable.
config: i386-randconfig-m021-20210927 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

smatch warnings:
drivers/hwmon/nct7802.c:714 nct7802_temp_is_visible() warn: compare has higher precedence than mask
drivers/hwmon/nct7802.c:714 nct7802_temp_is_visible() warn: add some parenthesis here?
drivers/hwmon/nct7802.c:1136 nct7802_configure_temperature_sensors_from_device_tree() error: uninitialized symbol 'type'.

vim +714 drivers/hwmon/nct7802.c

3434f378358043 Guenter Roeck 2014-06-29 696 static umode_t nct7802_temp_is_visible(struct kobject *kobj,
3434f378358043 Guenter Roeck 2014-06-29 697 struct attribute *attr, int index)
3434f378358043 Guenter Roeck 2014-06-29 698 {
d06f9e6c8960d1 hailizheng 2020-05-19 699 struct device *dev = kobj_to_dev(kobj);
3434f378358043 Guenter Roeck 2014-06-29 700 struct nct7802_data *data = dev_get_drvdata(dev);
3434f378358043 Guenter Roeck 2014-06-29 701 unsigned int reg;
3434f378358043 Guenter Roeck 2014-06-29 702 int err;
3434f378358043 Guenter Roeck 2014-06-29 703
3434f378358043 Guenter Roeck 2014-06-29 704 err = regmap_read(data->regmap, REG_MODE, &reg);
3434f378358043 Guenter Roeck 2014-06-29 705 if (err < 0)
3434f378358043 Guenter Roeck 2014-06-29 706 return 0;
3434f378358043 Guenter Roeck 2014-06-29 707
0654ba359c66a7 Oskar Senft 2021-09-20 708 if (index >= 0 && index < 20 && /* RD1, RD 2*/
0654ba359c66a7 Oskar Senft 2021-09-20 709 ((reg >> MODE_BIT_OFFSET_RTD(index / 10)) & MODE_RTD_MASK) != 0x01 &&
0654ba359c66a7 Oskar Senft 2021-09-20 710 ((reg >> MODE_BIT_OFFSET_RTD(index / 10)) & MODE_RTD_MASK) != 0x02)
3434f378358043 Guenter Roeck 2014-06-29 711 return 0;
fcdc5739dce03d Constantine Shulyupin 2015-07-01 712
0654ba359c66a7 Oskar Senft 2021-09-20 713 if (index >= 20 && index < 30 && /* RD3 */
0654ba359c66a7 Oskar Senft 2021-09-20 @714 (reg >> MODE_BIT_OFFSET_RTD(index / 10) & MODE_RTD_MASK != 0x02))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This is a precedence bug. There are extra parentheses here but they're
in the wrong place. It should be:

if (index >= 20 && index < 30 && /* RD3 */
(reg >> MODE_BIT_OFFSET_RTD(index / 10) & MODE_RTD_MASK) != 0x02)
return 0;

3434f378358043 Guenter Roeck 2014-06-29 715 return 0;
fcdc5739dce03d Constantine Shulyupin 2015-07-01 716
0654ba359c66a7 Oskar Senft 2021-09-20 717 if (index >= 30 && index < 38 && /* local */
0654ba359c66a7 Oskar Senft 2021-09-20 718 (reg & MODE_LTD_EN) != MODE_LTD_EN)
0654ba359c66a7 Oskar Senft 2021-09-20 719 return 0;
3434f378358043 Guenter Roeck 2014-06-29 720
3434f378358043 Guenter Roeck 2014-06-29 721 err = regmap_read(data->regmap, REG_PECI_ENABLE, &reg);
3434f378358043 Guenter Roeck 2014-06-29 722 if (err < 0)
3434f378358043 Guenter Roeck 2014-06-29 723 return 0;
3434f378358043 Guenter Roeck 2014-06-29 724
fcdc5739dce03d Constantine Shulyupin 2015-07-01 725 if (index >= 38 && index < 46 && !(reg & 0x01)) /* PECI 0 */
3434f378358043 Guenter Roeck 2014-06-29 726 return 0;
3434f378358043 Guenter Roeck 2014-06-29 727
fcdc5739dce03d Constantine Shulyupin 2015-07-01 728 if (index >= 0x46 && (!(reg & 0x02))) /* PECI 1 */
3434f378358043 Guenter Roeck 2014-06-29 729 return 0;
3434f378358043 Guenter Roeck 2014-06-29 730
3434f378358043 Guenter Roeck 2014-06-29 731 return attr->mode;
3434f378358043 Guenter Roeck 2014-06-29 732 }

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