From 1b079ca2c2e9a4652051bc4b62a5ef83d59d86bb Mon Sep 17 00:00:00 2001 From: Charles Keepax Date: Thu, 15 Feb 2018 17:52:17 +0000 Subject: [PATCH] regmap: Tidy up regmap_raw_read chunking code Raw reads may need to be split into small chunks if max_raw_read is set. Tidy up the code implementing this, the new code is slightly clearer, slightly shorter and slightly more efficient. Signed-off-by: Charles Keepax Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 44 ++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 25 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 0cc7387008c9..ff30a9157de5 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -2542,44 +2542,38 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val, if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass || map->cache_type == REGCACHE_NONE) { - int chunk_stride = map->reg_stride; - size_t chunk_size = val_bytes; - size_t chunk_count = val_count; + size_t chunk_count, chunk_bytes; + size_t chunk_regs = val_count; if (!map->bus->read) { ret = -ENOTSUPP; goto out; } - if (!map->use_single_read) { - if (map->max_raw_read) - chunk_size = map->max_raw_read; - else - chunk_size = val_len; - if (chunk_size % val_bytes) - chunk_size -= chunk_size % val_bytes; - chunk_count = val_len / chunk_size; - chunk_stride *= chunk_size / val_bytes; - } + if (map->use_single_read) + chunk_regs = 1; + else if (map->max_raw_read && val_len > map->max_raw_read) + chunk_regs = map->max_raw_read / val_bytes; - /* Read bytes that fit into a multiple of chunk_size */ + chunk_count = val_count / chunk_regs; + chunk_bytes = chunk_regs * val_bytes; + + /* Read bytes that fit into whole chunks */ for (i = 0; i < chunk_count; i++) { - ret = _regmap_raw_read(map, - reg + (i * chunk_stride), - val + (i * chunk_size), - chunk_size); + ret = _regmap_raw_read(map, reg, val, chunk_bytes); if (ret != 0) - return ret; + goto out; + + reg += regmap_get_offset(map, chunk_regs); + val += chunk_bytes; + val_len -= chunk_bytes; } /* Read remaining bytes */ - if (chunk_size * i < val_len) { - ret = _regmap_raw_read(map, - reg + (i * chunk_stride), - val + (i * chunk_size), - val_len - i * chunk_size); + if (val_len) { + ret = _regmap_raw_read(map, reg, val, val_len); if (ret != 0) - return ret; + goto out; } } else { /* Otherwise go word by word for the cache; should be low