[PATCH 1/3] regmap: flat: use the cache_present bitmap

From: Ionut Nicu
Date: Fri Aug 09 2013 - 06:09:57 EST


As opposed to the other regmap cache implementations,
regcache_flat didn't use the cache_present bitmap for
figuring out whether a register was cached or not, nor
did it mark a register as present in the cache when
regcache_flat_write() was called.

This caused incorrect behaviour, such as returning
value 0 for non-volatile registers without first reading
their value from the device and storing it in the cache.

Signed-off-by: Ionut Nicu <ioan.nicu.ext@xxxxxxx>
---
drivers/base/regmap/regcache-flat.c | 25 ++++++++++++++++++++++---
1 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/base/regmap/regcache-flat.c b/drivers/base/regmap/regcache-flat.c
index d9762e4..f47278e 100644
--- a/drivers/base/regmap/regcache-flat.c
+++ b/drivers/base/regmap/regcache-flat.c
@@ -16,9 +16,13 @@

#include "internal.h"

+static int regcache_flat_write(struct regmap *map, unsigned int reg,
+ unsigned int value);
+static int regcache_flat_exit(struct regmap *map);
+
static int regcache_flat_init(struct regmap *map)
{
- int i;
+ int i, ret;
unsigned int *cache;

map->cache = kzalloc(sizeof(unsigned int) * (map->max_register + 1),
@@ -28,8 +32,15 @@ static int regcache_flat_init(struct regmap *map)

cache = map->cache;

- for (i = 0; i < map->num_reg_defaults; i++)
- cache[map->reg_defaults[i].reg] = map->reg_defaults[i].def;
+ for (i = 0; i < map->num_reg_defaults; i++) {
+ ret = regcache_flat_write(map,
+ map->reg_defaults[i].reg,
+ map->reg_defaults[i].def);
+ if (ret) {
+ regcache_flat_exit(map);
+ return ret;
+ }
+ }

return 0;
}
@@ -47,6 +58,9 @@ static int regcache_flat_read(struct regmap *map,
{
unsigned int *cache = map->cache;

+ if (!regcache_reg_present(map, reg))
+ return -ENOENT;
+
*value = cache[reg];

return 0;
@@ -56,6 +70,11 @@ static int regcache_flat_write(struct regmap *map, unsigned int reg,
unsigned int value)
{
unsigned int *cache = map->cache;
+ int ret;
+
+ ret = regcache_set_reg_present(map, reg);
+ if (ret < 0)
+ return ret;

cache[reg] = value;

--
1.7.1

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