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authorLinus Torvalds <torvalds@linux-foundation.org>2016-09-06 11:02:36 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-09-06 11:02:36 -0700
commitec9a03d47ed71364501c54ce3845af0bd81ff2f6 (patch)
tree0f0397b69c91101d7ad013b9f3f8ba2f13a2d4ce /drivers
parent8ded8f0030b9b44e9dcf48ce2421f9502cece39b (diff)
parent787ad90332b3573d502a6c1aff52f708ca141976 (diff)
Merge tag 'regmap-fix-v4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap fixes from Mark Brown: "Several fixes here, the main one being the change from Lars-Peter which I'd been letting soak in -next since the merge window in case it uncovered further issues as it's a minimal fix rather than a change addressing the root cause of the problems (which would've been too invasive for -rc): - The biggest change is a fix from Lars-Peter to ensure that we don't create overlapping rbtree nodes which in turn avoids returning corrupt cache values to users, fixing some issues that were exposed by some recent optimisations with certain access patterns but had been present for a long time. - A fix from Elaine Zhang to stop us updating the cache if we get an I/O error when writing to the hardware. - A fix fromm Maarten ter Huurne to avoid uninitialized defaults in cases where we have non-readable registers but are initializing the cache by reading from the device" * tag 'regmap-fix-v4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: drop cache if the bus transfer error regmap: rbtree: Avoid overlapping nodes regmap: cache: Fix num_reg_defaults computation from reg_defaults_raw
Diffstat (limited to 'drivers')
-rw-r--r--drivers/base/regmap/regcache-rbtree.c38
-rw-r--r--drivers/base/regmap/regcache.c5
-rw-r--r--drivers/base/regmap/regmap.c2
3 files changed, 33 insertions, 12 deletions
diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index aa56af87d941..b11af3f2c1db 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -404,6 +404,7 @@ static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
unsigned int new_base_reg, new_top_reg;
unsigned int min, max;
unsigned int max_dist;
+ unsigned int dist, best_dist = UINT_MAX;
max_dist = map->reg_stride * sizeof(*rbnode_tmp) /
map->cache_word_size;
@@ -423,24 +424,41 @@ static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
&base_reg, &top_reg);
if (base_reg <= max && top_reg >= min) {
- new_base_reg = min(reg, base_reg);
- new_top_reg = max(reg, top_reg);
- } else {
- if (max < base_reg)
- node = node->rb_left;
+ if (reg < base_reg)
+ dist = base_reg - reg;
+ else if (reg > top_reg)
+ dist = reg - top_reg;
else
- node = node->rb_right;
-
- continue;
+ dist = 0;
+ if (dist < best_dist) {
+ rbnode = rbnode_tmp;
+ best_dist = dist;
+ new_base_reg = min(reg, base_reg);
+ new_top_reg = max(reg, top_reg);
+ }
}
- ret = regcache_rbtree_insert_to_block(map, rbnode_tmp,
+ /*
+ * Keep looking, we want to choose the closest block,
+ * otherwise we might end up creating overlapping
+ * blocks, which breaks the rbtree.
+ */
+ if (reg < base_reg)
+ node = node->rb_left;
+ else if (reg > top_reg)
+ node = node->rb_right;
+ else
+ break;
+ }
+
+ if (rbnode) {
+ ret = regcache_rbtree_insert_to_block(map, rbnode,
new_base_reg,
new_top_reg, reg,
value);
if (ret)
return ret;
- rbtree_ctx->cached_rbnode = rbnode_tmp;
+ rbtree_ctx->cached_rbnode = rbnode;
return 0;
}
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;
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);