[PATCH 1/5] regmap: Move the handling for max_raw_read into regmap_raw_read

From: Charles Keepax
Date: Thu Feb 15 2018 - 12:53:44 EST


Currently regmap_bulk_read will split a read into chunks before
calling regmap_raw_read if max_raw_read is set. It is more logical for
this handling to be inside regmap_raw_read itself, as this removes the
need to keep re-implementing the chunking code, which would be the
same for all users of regmap_raw_read.

Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/base/regmap/regmap.c | 90 +++++++++++++++++---------------------------
1 file changed, 35 insertions(+), 55 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 6342eaefc218..f78ddaa9a1e8 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -2542,18 +2542,45 @@ 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;
+
if (!map->bus->read) {
ret = -ENOTSUPP;
goto out;
}
- if (map->max_raw_read && map->max_raw_read < val_len) {
- ret = -E2BIG;
- 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;
}

- /* Physical block read if there's no cache involved */
- ret = _regmap_raw_read(map, reg, val, val_len);
+ /* Read bytes that fit into a multiple of chunk_size */
+ for (i = 0; i < chunk_count; i++) {
+ ret = _regmap_raw_read(map,
+ reg + (i * chunk_stride),
+ val + (i * chunk_size),
+ chunk_size);
+ if (ret != 0)
+ return ret;
+ }

+ /* 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 (ret != 0)
+ return ret;
+ }
} else {
/* Otherwise go word by word for the cache; should be low
* cost as we expect to hit the cache.
@@ -2655,56 +2682,9 @@ int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
return -EINVAL;

if (map->bus && map->format.parse_inplace && (vol || map->cache_type == REGCACHE_NONE)) {
- /*
- * Some devices does not support bulk read, for
- * them we have a series of single read operations.
- */
- size_t total_size = val_bytes * val_count;
-
- if (!map->use_single_read &&
- (!map->max_raw_read || map->max_raw_read > total_size)) {
- ret = regmap_raw_read(map, reg, val,
- val_bytes * val_count);
- if (ret != 0)
- return ret;
- } else {
- /*
- * Some devices do not support bulk read or do not
- * support large bulk reads, for them we have a series
- * of read operations.
- */
- int chunk_stride = map->reg_stride;
- size_t chunk_size = val_bytes;
- size_t chunk_count = val_count;
-
- if (!map->use_single_read) {
- chunk_size = map->max_raw_read;
- if (chunk_size % val_bytes)
- chunk_size -= chunk_size % val_bytes;
- chunk_count = total_size / chunk_size;
- chunk_stride *= chunk_size / val_bytes;
- }
-
- /* Read bytes that fit into a multiple of chunk_size */
- for (i = 0; i < chunk_count; i++) {
- ret = regmap_raw_read(map,
- reg + (i * chunk_stride),
- val + (i * chunk_size),
- chunk_size);
- if (ret != 0)
- return ret;
- }
-
- /* Read remaining bytes */
- if (chunk_size * i < total_size) {
- ret = regmap_raw_read(map,
- reg + (i * chunk_stride),
- val + (i * chunk_size),
- total_size - i * chunk_size);
- if (ret != 0)
- return ret;
- }
- }
+ ret = regmap_raw_read(map, reg, val, val_bytes * val_count);
+ if (ret != 0)
+ return ret;

for (i = 0; i < val_count * val_bytes; i += val_bytes)
map->format.parse_inplace(val + i);
--
2.11.0