diff options
| author | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2012-02-21 19:12:47 +0000 |
|---|---|---|
| committer | Simone Willett <swillett@nvidia.com> | 2012-04-15 13:28:12 -0700 |
| commit | 8f010007a636b19728dd504bdf986d13e416cc67 (patch) | |
| tree | 17d7135c53932b44ba65d003222a729731266872 /drivers/base | |
| parent | 4905e92c32deb4438361f3e52f3355aa877728ff (diff) | |
regmap: Support raw reads from cached registers
Fall back to a register by register read to do so; most likely we'll be
cache only so the overhead will be low.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
(cherry picked from commit b8fb5ab156055b745254609f4635fcfd6b7dabc8)
Change-Id: I9f3b6011f4704987c5a014de8b30a2e6e3196d21
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/96482
Reviewed-by: Simone Willett <swillett@nvidia.com>
Tested-by: Simone Willett <swillett@nvidia.com>
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/regmap/regmap.c | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index e5ae78623fb7..fdea9b67255f 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -711,16 +711,32 @@ EXPORT_SYMBOL_GPL(regmap_read); int regmap_raw_read(struct regmap *map, unsigned int reg, void *val, size_t val_len) { - size_t val_count = val_len / map->format.val_bytes; - int ret; - - WARN_ON(!regmap_volatile_range(map, reg, val_count) && - map->cache_type != REGCACHE_NONE); + size_t val_bytes = map->format.val_bytes; + size_t val_count = val_len / val_bytes; + unsigned int v; + int ret, i; mutex_lock(&map->lock); - ret = _regmap_raw_read(map, reg, val, val_len); + if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass || + map->cache_type == REGCACHE_NONE) { + /* Physical block read if there's no cache involved */ + ret = _regmap_raw_read(map, reg, val, val_len); + + } else { + /* Otherwise go word by word for the cache; should be low + * cost as we expect to hit the cache. + */ + for (i = 0; i < val_count; i++) { + ret = _regmap_read(map, reg + i, &v); + if (ret != 0) + goto out; + + map->format.format_val(val + (i * val_bytes), v); + } + } + out: mutex_unlock(&map->lock); return ret; |