linux-stable.git/drivers/base/regmap/regcache.c, branch v3.3.4

regmap: Fix cache defaults initialization from raw cache defaults

2012-02-15T16:31:32+00:00

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 
Signed-off-by: Mark Brown 
Cc: stable@vger.kernel.org

regmap: Add trace event for successful cache reads

2011-11-30T20:51:09+00:00

Currently we only trace physical reads, there's no instrumentation if
the read is satisfied from cache.

Signed-off-by: Mark Brown

regmap: Remove indexed cache type

2011-11-20T20:56:34+00:00

There should be no situation where it offers any advantage over rbtree
and there are no current users so remove the code for simplicity.

Signed-off-by: Mark Brown

regmap: Drop check whether a register is readable in regcache_read

2011-11-17T16:51:27+00:00

One of the reasons for using a cache is to have a software shadow of a register
which is writable but not readable. This allows us to do a read-modify-write
operation on such a register.

Currently regcache checks whether a register is readable when performing a
cached read and returns an error if it is not. Drop this check, since it will
prevent us from using the cache for registers where read-back is not possible.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Mark Brown

regmap: Properly round cache_word_size

2011-11-17T16:51:23+00:00

regcache currently only properly works with val bit sizes of 8 or 16, since
it will, when calculating the cache word size, round down. This causes the
cache storage to be too small to hold the full register value. Fix this by
rounding up instead.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Mark Brown

regmap: Make reg_config reg_defaults const

2011-11-16T17:34:53+00:00

The reg_defaults field usually points to a static per driver array, which should
not be modified. Make requirement this explicit by making reg_defaults const.
To allow this the regcache_init code needs some minor changes. Previoulsy the
reg_config was not available in regcache_init and regmap->reg_defaults was used
to pass the default register set to regcache_init. Now that the reg_config is
available we can work on it directly.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Mark Brown

regmap: Move initialization of regcache related fields to regcache_init

2011-11-16T17:34:53+00:00

Move the initialization regcache related fields of the regmap struct to
regcache_init. This allows us to keep regmap and regcache code better
separated.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Mark Brown

regmap: Fix memory leak in regcache_init error path

2011-11-14T21:46:25+00:00

Make sure all allocated memory gets freed again in case initializing the cache
failed.

Signed-off-by: Lars-Peter Clausen 
Acked-by: Dimitris Papastamos 
Signed-off-by: Mark Brown

regmap: Fix memory leak in regcache_hw_init error path

2011-11-14T21:46:09+00:00

Make sure reg_defaults_raw gets freed in case of an error.

Signed-off-by: Lars-Peter Clausen 
Acked-by: Dimitris Papastamos 
Signed-off-by: Mark Brown

regmap: Track if the register cache is dirty and suppress unneeded syncs

2011-11-08T11:38:15+00:00

Allow drivers to optimise out the register cache sync if they didn't need
to do one. If the hardware is desynced from the register cache (by power
loss for example) then the driver should call regcache_mark_dirty() to
let the core know about this.

Signed-off-by: Mark Brown