Re: [PATCH v2] serio: PS2 gpio bit banging driver for the serio bus

[kbuild test robot]

Hi Danilo,

[auto build test WARNING on input/next]
[also build test WARNING on v4.13-rc3 next-20170731]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Danilo-Krummrich/serio-PS2-gpio-bit-banging-driver-for-the-serio-bus/20170801-081531
base:   https://git.kernel.org/pub/scm/linux/kernel/git/dtor/input.git next
config: blackfin-allyesconfig (attached as .config)
compiler: bfin-uclinux-gcc (GCC) 6.2.0
reproduce:
        wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=blackfin 

Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings

All warnings (new ones prefixed by >>):

   In file included from arch/blackfin/include/asm/gpio.h:191:0,
                    from include/linux/gpio.h:48,
                    from drivers/input/serio/ps2-gpio.c:11:
   drivers/input/serio/ps2-gpio.c: In function 'ps2_gpio_irq':
>> include/asm-generic/gpio.h:103:9: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized]
     return gpiod_set_raw_value(gpio_to_desc(gpio), value);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/input/serio/ps2-gpio.c:191:6: note: 'data' was declared here
     int data;
         ^~~~

vim +/data +103 include/asm-generic/gpio.h

d2876d08 David Brownell    2008-02-04   91  
d2876d08 David Brownell    2008-02-04   92  
d2876d08 David Brownell    2008-02-04   93  /* A platform's <asm/gpio.h> code may want to inline the I/O calls when
d2876d08 David Brownell    2008-02-04   94   * the GPIO is constant and refers to some always-present controller,
d2876d08 David Brownell    2008-02-04   95   * giving direct access to chip registers and tight bitbanging loops.
d2876d08 David Brownell    2008-02-04   96   */
79a9becd Alexandre Courbot 2013-10-17   97  static inline int __gpio_get_value(unsigned gpio)
79a9becd Alexandre Courbot 2013-10-17   98  {
79a9becd Alexandre Courbot 2013-10-17   99  	return gpiod_get_raw_value(gpio_to_desc(gpio));
79a9becd Alexandre Courbot 2013-10-17  100  }
79a9becd Alexandre Courbot 2013-10-17  101  static inline void __gpio_set_value(unsigned gpio, int value)
79a9becd Alexandre Courbot 2013-10-17  102  {
79a9becd Alexandre Courbot 2013-10-17 @103  	return gpiod_set_raw_value(gpio_to_desc(gpio), value);
79a9becd Alexandre Courbot 2013-10-17  104  }
d2876d08 David Brownell    2008-02-04  105  

:::::: The code at line 103 was first introduced by commit
:::::: 79a9becda8940deb2274b5aa4577c86d52ee7ecb gpiolib: export descriptor-based GPIO interface

:::::: TO: Alexandre Courbot <acourbot@xxxxxxxxxx>
:::::: CC: Linus Walleij <linus.walleij@xxxxxxxxxx>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

Attachment: .config.gz
Description: application/gzip