diff options
Diffstat (limited to 'drivers/base/regmap/regcache.c')
| -rw-r--r-- | drivers/base/regmap/regcache.c | 45 |
1 files changed, 30 insertions, 15 deletions
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c index 7eb7b3b98..b9862d741 100644 --- a/drivers/base/regmap/regcache.c +++ b/drivers/base/regmap/regcache.c @@ -249,6 +249,22 @@ int regcache_write(struct regmap *map, return 0; } +static bool regcache_reg_needs_sync(struct regmap *map, unsigned int reg, + unsigned int val) +{ + int ret; + + /* If we don't know the chip just got reset, then sync everything. */ + if (!map->no_sync_defaults) + return true; + + /* Is this the hardware default? If so skip. */ + ret = regcache_lookup_reg(map, reg); + if (ret >= 0 && val == map->reg_defaults[ret].def) + return false; + return true; +} + static int regcache_default_sync(struct regmap *map, unsigned int min, unsigned int max) { @@ -266,9 +282,7 @@ static int regcache_default_sync(struct regmap *map, unsigned int min, if (ret) return ret; - /* Is this the hardware default? If so skip. */ - ret = regcache_lookup_reg(map, reg); - if (ret >= 0 && val == map->reg_defaults[ret].def) + if (!regcache_reg_needs_sync(map, reg, val)) continue; map->cache_bypass = 1; @@ -342,6 +356,7 @@ out: /* Restore the bypass state */ map->async = false; map->cache_bypass = bypass; + map->no_sync_defaults = false; map->unlock(map->lock_arg); regmap_async_complete(map); @@ -397,6 +412,7 @@ out: /* Restore the bypass state */ map->cache_bypass = bypass; map->async = false; + map->no_sync_defaults = false; map->unlock(map->lock_arg); regmap_async_complete(map); @@ -461,18 +477,23 @@ void regcache_cache_only(struct regmap *map, bool enable) EXPORT_SYMBOL_GPL(regcache_cache_only); /** - * regcache_mark_dirty: Mark the register cache as dirty + * regcache_mark_dirty: Indicate that HW registers were reset to default values * * @map: map to mark * - * Mark the register cache as dirty, for example due to the device - * having been powered down for suspend. If the cache is not marked - * as dirty then the cache sync will be suppressed. + * Inform regcache that the device has been powered down or reset, so that + * on resume, regcache_sync() knows to write out all non-default values + * stored in the cache. + * + * If this function is not called, regcache_sync() will assume that + * the hardware state still matches the cache state, modulo any writes that + * happened when cache_only was true. */ void regcache_mark_dirty(struct regmap *map) { map->lock(map->lock_arg); map->cache_dirty = true; + map->no_sync_defaults = true; map->unlock(map->lock_arg); } EXPORT_SYMBOL_GPL(regcache_mark_dirty); @@ -613,10 +634,7 @@ static int regcache_sync_block_single(struct regmap *map, void *block, continue; val = regcache_get_val(map, block, i); - - /* Is this the hardware default? If so skip. */ - ret = regcache_lookup_reg(map, regtmp); - if (ret >= 0 && val == map->reg_defaults[ret].def) + if (!regcache_reg_needs_sync(map, regtmp, val)) continue; map->cache_bypass = 1; @@ -688,10 +706,7 @@ static int regcache_sync_block_raw(struct regmap *map, void *block, } val = regcache_get_val(map, block, i); - - /* Is this the hardware default? If so skip. */ - ret = regcache_lookup_reg(map, regtmp); - if (ret >= 0 && val == map->reg_defaults[ret].def) { + if (!regcache_reg_needs_sync(map, regtmp, val)) { ret = regcache_sync_block_raw_flush(map, &data, base, regtmp); if (ret != 0) |