regmap: Drop check whether a register is readable in regcache_read

One of the reasons for using a cache is to have a software shadow of a register
which is writable but not readable. This allows us to do a read-modify-write
operation on such a register.

Currently regcache checks whether a register is readable when performing a
cached read and returns an error if it is not. Drop this check, since it will
prevent us from using the cache for registers where read-back is not possible.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 6d93e49c462f18dcf595c3a2bbc445b0fe45f167..e21eebd36afab27d884c857bd07b96414ca86f33 100644 (file)
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -199,9 +199,6 @@ int regcache_read(struct regmap *map,
 
        BUG_ON(!map->cache_ops);
 
-       if (!regmap_readable(map, reg))
-               return -EIO;
-
        if (!regmap_volatile(map, reg))
                return map->cache_ops->read(map, reg, value);