[PATCH 4.19 232/245] regmap: fix page selection for noinc reads

From: Greg Kroah-Hartman
Date: Tue Sep 29 2020 - 08:19:43 EST


From: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

[ Upstream commit 4003324856311faebb46cbd56a1616bd3f3b67c2 ]

Non-incrementing reads can fail if register + length crosses page
border. However for non-incrementing reads we should not check for page
border crossing. Fix this by passing additional flag to _regmap_raw_read
and passing length to _regmap_select_page basing on the flag.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Fixes: 74fe7b551f33 ("regmap: Add regmap_noinc_read API")
Link: https://lore.kernel.org/r/20200917153405.3139200-1-dmitry.baryshkov@xxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/base/regmap/regmap.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index d26b485ccc7d0..e8b3353c18eb8 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -2367,7 +2367,7 @@ int regmap_raw_write_async(struct regmap *map, unsigned int reg,
EXPORT_SYMBOL_GPL(regmap_raw_write_async);

static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
- unsigned int val_len)
+ unsigned int val_len, bool noinc)
{
struct regmap_range_node *range;
int ret;
@@ -2380,7 +2380,7 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
range = _regmap_range_lookup(map, reg);
if (range) {
ret = _regmap_select_page(map, &reg, range,
- val_len / map->format.val_bytes);
+ noinc ? 1 : val_len / map->format.val_bytes);
if (ret != 0)
return ret;
}
@@ -2418,7 +2418,7 @@ static int _regmap_bus_read(void *context, unsigned int reg,
if (!map->format.parse_val)
return -EINVAL;

- ret = _regmap_raw_read(map, reg, work_val, map->format.val_bytes);
+ ret = _regmap_raw_read(map, reg, work_val, map->format.val_bytes, false);
if (ret == 0)
*val = map->format.parse_val(work_val);

@@ -2536,7 +2536,7 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,

/* Read bytes that fit into whole chunks */
for (i = 0; i < chunk_count; i++) {
- ret = _regmap_raw_read(map, reg, val, chunk_bytes);
+ ret = _regmap_raw_read(map, reg, val, chunk_bytes, false);
if (ret != 0)
goto out;

@@ -2547,7 +2547,7 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,

/* Read remaining bytes */
if (val_len) {
- ret = _regmap_raw_read(map, reg, val, val_len);
+ ret = _regmap_raw_read(map, reg, val, val_len, false);
if (ret != 0)
goto out;
}
@@ -2622,7 +2622,7 @@ int regmap_noinc_read(struct regmap *map, unsigned int reg,
read_len = map->max_raw_read;
else
read_len = val_len;
- ret = _regmap_raw_read(map, reg, val, read_len);
+ ret = _regmap_raw_read(map, reg, val, read_len, true);
if (ret)
goto out_unlock;
val = ((u8 *)val) + read_len;
--
2.25.1