[PATCH] regmap: Format data for raw write in regmap_bulk_write

From: Charles Keepax
Date: Thu Feb 22 2018 - 07:59:10 EST


In the case were the bulk transaction is split up into smaller chunks
data is passed directly to regmap_raw_write. However regmap_bulk_write
uses data in host endian and regmap_raw_write expects data in device
endian. As such if the host and device differ in endian the wrong data
will be written to the device. Correct this issue using a similar
approach to the single raw write case below it, duplicate the data
into a new buffer and use parse_inplace to format the data correctly.

Fixes: adaac459759d ("regmap: Introduce max_raw_read/write for regmap_bulk_read/write")
Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/base/regmap/regmap.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index f5d653663626..8fe6e08fa41e 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -2003,6 +2003,17 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
int chunk_stride = map->reg_stride;
size_t chunk_size = val_bytes;
size_t chunk_count = val_count;
+ void *wval;
+
+ if (!val_count)
+ return -EINVAL;
+
+ wval = kmemdup(val, val_count * val_bytes, map->alloc_flags);
+ if (!wval)
+ return -ENOMEM;
+
+ for (i = 0; i < val_count * val_bytes; i += val_bytes)
+ map->format.parse_inplace(wval + i);

if (!map->use_single_write) {
chunk_size = map->max_raw_write;
@@ -2017,7 +2028,7 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
for (i = 0; i < chunk_count; i++) {
ret = _regmap_raw_write(map,
reg + (i * chunk_stride),
- val + (i * chunk_size),
+ wval + (i * chunk_size),
chunk_size);
if (ret)
break;
@@ -2026,10 +2037,12 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
/* Write remaining bytes */
if (!ret && chunk_size * i < total_size) {
ret = _regmap_raw_write(map, reg + (i * chunk_stride),
- val + (i * chunk_size),
+ wval + (i * chunk_size),
total_size - i * chunk_size);
}
map->unlock(map->lock_arg);
+
+ kfree(wval);
} else {
void *wval;

--
2.16.1