From e7662bced2e98ffa2c572126677deb9cf55d43b3 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 5 Mar 2026 09:53:02 +0100 Subject: [PATCH] regcache: Move HW readback after cache initialisation Make sure that cache is initialised before calling any IO using regmap, this makes sure that we won't access NULL or invalid pointers in the cache which hasn't been initialised. As a side effect it also makes the ordering of cleaning up the resources in regcache_exit() to be the same (and correct) as in the error path of regcache_init(). This is not a problem right now as they do not have dependencies, but it makes code robust against potential changes in the future. Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20260305085449.3184020-4-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown --- drivers/base/regmap/regcache.c | 27 +++++++++++++++------------ 1 file changed, 15 insertions(+), 12 deletions(-) diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c index e9d95aa63938..27616b05111c 100644 --- a/drivers/base/regmap/regcache.c +++ b/drivers/base/regmap/regcache.c @@ -200,14 +200,6 @@ int regcache_init(struct regmap *map, const struct regmap_config *config) map->reg_defaults = kmalloc_objs(struct reg_default, count); if (!map->reg_defaults) return -ENOMEM; - - /* Some devices such as PMICs don't have cache defaults, - * we cope with this by reading back the HW registers and - * crafting the cache defaults by hand. - */ - ret = regcache_hw_init(map); - if (ret < 0) - goto err_free_reg_defaults; } if (!map->max_register_is_set && map->num_reg_defaults_raw) { @@ -222,7 +214,18 @@ int regcache_init(struct regmap *map, const struct regmap_config *config) ret = map->cache_ops->init(map); map->unlock(map->lock_arg); if (ret) - goto err_free; + goto err_free_reg_defaults; + } + + /* + * Some devices such as PMICs don't have cache defaults, + * we cope with this by reading back the HW registers and + * crafting the cache defaults by hand. + */ + if (count) { + ret = regcache_hw_init(map); + if (ret) + goto err_exit; } if (map->cache_ops->populate && @@ -232,10 +235,12 @@ int regcache_init(struct regmap *map, const struct regmap_config *config) ret = map->cache_ops->populate(map); map->unlock(map->lock_arg); if (ret) - goto err_exit; + goto err_free; } return 0; +err_free: + regcache_hw_exit(map); err_exit: if (map->cache_ops->exit) { dev_dbg(map->dev, "Destroying %s cache\n", map->cache_ops->name); @@ -243,8 +248,6 @@ int regcache_init(struct regmap *map, const struct regmap_config *config) ret = map->cache_ops->exit(map); map->unlock(map->lock_arg); } -err_free: - regcache_hw_exit(map); err_free_reg_defaults: kfree(map->reg_defaults);