re: fbdev: ssd1307fb: Unify init code and obtain hw specific bits from DT

[Dan Carpenter <dan.carpenter@oracle.com>]

Hello Thomas Niederprüm,

The patch a3998fe03e87: "fbdev: ssd1307fb: Unify init code and obtain
hw specific bits from DT" from Mar 31, 2015, leads to the following
static checker warning:

	drivers/video/fbdev/ssd1307fb.c:371 ssd1307fb_init()
	warn: add some parenthesis here?

drivers/video/fbdev/ssd1307fb.c
   366          /* Set COM pins configuration */
   367          ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG);
   368          if (ret < 0)
   369                  return ret;
   370  
   371          compins = 0x02 | (!par->com_seq & 0x1) << 4
   372                                     | (par->com_lrremap & 0x1) << 5;

Smatch is complaining because it's normally  "!par->com_seq & 0x1" is
a bug and "!(par->com_seq & 0x1)" is intended.  I don't know what was
intended here though.  If the current code is correct, you can silence
the static checker warning by writing it as "(!par->com_seq) & 0x1".

But I also have a hard time remembering if | or << is higher precedence
so that might be clearer with parenthesis as well even though the code
is clearly correct when I google for "order of operations" in C.

   373          ret = ssd1307fb_write_cmd(par->client, compins);
   374          if (ret < 0)
   375                  return ret;

regards,
dan carpenter