From b2c7f5d9c939a37c1ce7f86a642de70e3033ee9e Mon Sep 17 00:00:00 2001 From: Maarten ter Huurne Date: Fri, 29 Jul 2016 23:42:12 +0200 Subject: [PATCH 1/2] regmap: cache: Fix num_reg_defaults computation from reg_defaults_raw In 3245d460 (regmap: cache: Fall back to register by register read for cache defaults) non-readable registers are skipped when initializing reg_defaults, but are still included in num_reg_defaults. So there can be uninitialized entries at the end of reg_defaults, which can cause problems when the register cache initializes from the full array. Fixed it by excluding non-readable registers from the count as well. Signed-off-by: Maarten ter Huurne Signed-off-by: Mark Brown --- drivers/base/regmap/regcache.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c index df7ff7290821..4e582561e1e7 100644 --- a/drivers/base/regmap/regcache.c +++ b/drivers/base/regmap/regcache.c @@ -38,10 +38,11 @@ static int regcache_hw_init(struct regmap *map) /* calculate the size of reg_defaults */ for (count = 0, i = 0; i < map->num_reg_defaults_raw; i++) - if (!regmap_volatile(map, i * map->reg_stride)) + if (regmap_readable(map, i * map->reg_stride) && + !regmap_volatile(map, i * map->reg_stride)) count++; - /* all registers are volatile, so just bypass */ + /* all registers are unreadable or volatile, so just bypass */ if (!count) { map->cache_bypass = true; return 0; From 815806e39bf6f7e7b34875d4a9609dbe76661782 Mon Sep 17 00:00:00 2001 From: Elaine Zhang Date: Thu, 18 Aug 2016 17:01:55 +0800 Subject: [PATCH 2/2] regmap: drop cache if the bus transfer error regmap_write ->_regmap_raw_write -->regcache_write first and than use map->bus->write to wirte i2c or spi But if the i2c or spi transfer failed, But the cache is updated, So if I use regmap_read will get the cache data which is not the real register value. Signed-off-by: Elaine Zhang Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 51fa7d66a393..25d26bb18970 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1474,6 +1474,8 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg, ret = map->bus->write(map->bus_context, buf, len); kfree(buf); + } else if (ret != 0 && !map->cache_bypass && map->format.parse_val) { + regcache_drop_region(map, reg, reg + 1); } trace_regmap_hw_write_done(map, reg, val_len / map->format.val_bytes);