regmap: regmap: avoid spurious warning in regmap_read_debugfs

Gcc warns about the case where regmap_read_debugfs tries to walk an
empty map->debugfs_off_cache list, which would results in uninitialized
variable getting returned, if we hadn't checked the same condition
just before that.

After an originally suggested inferior patch from Arnd Bergmann,
this is the solution that Russell King came up with, sidestepping
the problem by merging the error case for an empty list with the
normal path.

Without this patch, building mxs_defconfig results in:

drivers/base/regmap/regmap-debugfs.c: In function 'regmap_read_debugfs':
drivers/base/regmap/regmap-debugfs.c:147:9: : warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]

Reported-by: Vincent Stehle <v-stehle@ti.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Russell King 2013-01-26 11:45:35 +00:00 committed by Mark Brown
parent 949db153b6
commit a3471469bc
1 changed files with 2 additions and 4 deletions

View File

@ -128,10 +128,8 @@ static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
* allocate and we should never be in this code if there are
* no registers at all.
*/
if (list_empty(&map->debugfs_off_cache)) {
WARN_ON(list_empty(&map->debugfs_off_cache));
return base;
}
WARN_ON(list_empty(&map->debugfs_off_cache));
ret = base;
/* Find the relevant block */
list_for_each_entry(c, &map->debugfs_off_cache, list) {