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regmap: Ensure regmap_register_patch() is compatible with fast_io 

With fast_io we use mutexes to lock the I/O operations so we would need
to do GFP_ATOMIC allocations if we wanted to do allocations inside the
lock as we do currently. Since it is unlikely that we will want to register
a patch outside of init where concurrency shouldn't be an issue move the
allocation of the patch data outside the lock.

Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Mark Brown 2014-03-18 10:53:26 +00:00
parent 38dbfb59d1
commit 56fb1c74f3
1 changed files with 14 additions and 11 deletions
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25
drivers/base/regmap/regmap.c
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@ -2173,6 +2173,9 @@ EXPORT_SYMBOL_GPL(regmap_async_complete);
* apply them immediately. Typically this is used to apply
* corrections to be applied to the device defaults on startup, such
* as the updates some vendors provide to undocumented registers.
*
* The caller must ensure that this function cannot be called
* concurrently with either itself or regcache_sync().
*/
int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
int num_regs)
@ -2185,6 +2188,17 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
num_regs))
return 0;
p = krealloc(map->patch,
sizeof(struct reg_default) * (map->patch_regs + num_regs),
GFP_KERNEL);
if (p) {
memcpy(p + map->patch_regs, regs, num_regs * sizeof(*regs));
map->patch = p;
map->patch_regs += num_regs;
} else {
return -ENOMEM;
}
map->lock(map->lock_arg);
bypass = map->cache_bypass;
@ -2202,17 +2216,6 @@ int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
}
}
p = krealloc(map->patch,
sizeof(struct reg_default) * (map->patch_regs + num_regs),
GFP_KERNEL);
if (p) {
memcpy(p + map->patch_regs, regs, num_regs * sizeof(*regs));
map->patch = p;
map->patch_regs += num_regs;
} else {
ret = -ENOMEM;
}
out:
map->async = false;
map->cache_bypass = bypass;