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regmap: Tidy up regmap_raw_read chunking code

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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 <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Charles Keepax 2018-02-15 17:52:17 +00:00 committed by Mark Brown
parent 0645ba4331
commit 1b079ca2c2
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GPG Key ID: 24D68B725D5487D0
1 changed files with 19 additions and 25 deletions
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44
drivers/base/regmap/regmap.c
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@ -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