[PATCH 4/7] regmap: Try cached read before checking if a hardware read is possible

From: Lars-Peter Clausen
Date: Wed Nov 16 2011 - 10:28:57 EST


For some register format types we do not provide a parse_val so we can not do a
hardware read. But a cached read is still possible, so try to read from the
cache first, before checking whether a hardware read is possible. Otherwise the
cache becomes pretty useless for these register types.

Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
---
drivers/base/regmap/regmap.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 3cf4785..b96cf72 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -434,15 +434,15 @@ static int _regmap_read(struct regmap *map, unsigned int reg,
{
int ret;

- if (!map->format.parse_val)
- return -EINVAL;
-
if (!map->cache_bypass) {
ret = regcache_read(map, reg, val);
if (ret == 0)
return 0;
}

+ if (!map->format.parse_val)
+ return -EINVAL;
+
if (map->cache_only)
return -EBUSY;

--
1.7.7.1


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