[PATCH] regmap: Drop early readability check

From: Mark Brown
Date: Thu Jun 15 2023 - 19:05:06 EST


We have some drivers that have a use case for cached write only
registers, doing read/modify/writes on read only registers in order to
work more easily with bitfields. Go back to trying the cache before we
check if we can read from the device.

Fixes: eab5abdeb79f0 ("regmap: Check for register readability before checking cache during read")
Reported-by: Konrad Dybcio <konradybcio@xxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/base/regmap/regmap.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index fad66b309ef9..89a7f1c459c1 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -2897,9 +2897,6 @@ static int _regmap_read(struct regmap *map, unsigned int reg,
int ret;
void *context = _regmap_map_get_context(map);

- if (!regmap_readable(map, reg))
- return -EIO;
-
if (!map->cache_bypass) {
ret = regcache_read(map, reg, val);
if (ret == 0)
@@ -2909,6 +2906,9 @@ static int _regmap_read(struct regmap *map, unsigned int reg,
if (map->cache_only)
return -EBUSY;

+ if (!regmap_readable(map, reg))
+ return -EIO;
+
ret = map->reg_read(context, reg, val);
if (ret == 0) {
if (regmap_should_log(map))

---
base-commit: 505cb70cd27abde24bd48b2c9a539cca485d722f
change-id: 20230615-regmap-drop-early-readability-3832b755ae14

Best regards,
--
Mark Brown <broonie@xxxxxxxxxx>