This is a note to let you know that I've just added the patch titled
regmap: Fix cache defaults initialization from raw cache defaults
to the 3.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
regmap-fix-cache-defaults-initialization-from-raw-cache-defaults.patch
and it can be found in the queue-3.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From 61cddc57dc14a5dffa0921d9a24fd68edbb374ac Mon Sep 17 00:00:00 2001
From: Lars-Peter Clausen <[email protected]>
Date: Wed, 15 Feb 2012 10:23:25 +0100
Subject: regmap: Fix cache defaults initialization from raw cache defaults
From: Lars-Peter Clausen <[email protected]>
commit 61cddc57dc14a5dffa0921d9a24fd68edbb374ac upstream.
Currently registers with a value of 0 are ignored when initializing the register
defaults from raw defaults. This worked in the past, because registers without a
explicit default were assumed to have a default value of 0. This was changed in
commit b03622a8 ("regmap: Ensure rbtree syncs registers set to zero properly").
As a result registers, which have a raw default value of 0 are now assumed to
have no default. This again can result in unnecessary writes when syncing the
cache. It will also result in unnecessary reads for e.g. the first update
operation. In the case where readback is not possible this will even let the
update operation fail, if the register has not been written to before.
So this patch removes the check. Instead it adds a check to ignore raw defaults
for registers which are volatile, since those registers are not cached.
Signed-off-by: Lars-Peter Clausen <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/base/regmap/regcache.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -54,7 +54,7 @@ static int regcache_hw_init(struct regma
for (count = 0, i = 0; i < map->num_reg_defaults_raw; i++) {
val = regcache_get_val(map->reg_defaults_raw,
i, map->cache_word_size);
- if (!val)
+ if (regmap_volatile(map, i))
continue;
count++;
}
@@ -69,7 +69,7 @@ static int regcache_hw_init(struct regma
for (i = 0, j = 0; i < map->num_reg_defaults_raw; i++) {
val = regcache_get_val(map->reg_defaults_raw,
i, map->cache_word_size);
- if (!val)
+ if (regmap_volatile(map, i))
continue;
map->reg_defaults[j].reg = i;
map->reg_defaults[j].def = val;
Patches currently in stable-queue which might be from [email protected] are
queue-3.2/regmap-fix-cache-defaults-initialization-from-raw-cache-defaults.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
