Commit Graph

322 Commits

Author SHA1 Message Date
Mark Brown a3c3774176 regmap: Skip hardware defaults for LZO caches
Saves some I/O when resyncing; we assume that syncs start from the device
reset state.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 20:12:49 +00:00
Dimitris Papastamos f0c2319f9f regmap: Expose the driver name in debugfs
Add a file called 'name' containing the name of the driver.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-22 14:24:45 +00:00
Dimitris Papastamos 09c6ecd394 regmap: Add support for writing to regmap registers via debugfs
To enable writing to the regmap debugfs registers file users will
need to modify the source directly and #define REGMAP_ALLOW_WRITE_DEBUGFS.
The reason for this is that it is dangerous to expose this
functionality in general where clients could potentially be PMICs.

[A couple of minor style updates -- broonie]

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-22 13:10:31 +00:00
Mark Brown b8fb5ab156 regmap: Support raw reads from cached registers
Fall back to a register by register read to do so; most likely we'll be
cache only so the overhead will be low.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-21 19:29:18 +00:00
Mark Brown aca1e172a1 Merge branch 'topic/patch' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into regmap-drivers 2012-02-20 21:21:33 +00:00
Mark Brown 3bf06a1ad9 Merge branch 'topic/devm' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into regmap-drivers 2012-02-20 21:21:25 +00:00
Mark Brown a6539c3294 regmap: Allow users to query the size of register values
Generic infrastructure based on top of regmap may want to operate on
blocks of data and therefore find it useful to find the size of the
register values. Provide an accessor operation for this.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-20 21:17:08 +00:00
Mark Brown 7d5e525b9c regmap: Implement support for 32 bit registers and values
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-17 16:26:50 -08:00
Laxman Dewangan df00c79f78 regmap: Bypassing cache when initializing cache
During regcache_init, if client has not passed the
default data of cached register then it is directly
read from the hw to initialize cache. This hw register
read happens before cache ops are initialized and hence
avoiding register read to check for the data available
on cache or not by enabling flag of cache_bypass.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-17 09:19:00 -08:00
Lars-Peter Clausen 61cddc57dc regmap: Fix cache defaults initialization from raw cache defaults
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 <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org
2012-02-15 08:31:32 -08:00
Laxman Dewangan 8eaeb21925 regmap: add regmap_bulk_write() for register write
The bulk_write() supports the data transfer to multi
register which takes the data into cpu_endianness format
and does formatting of data to device format before
sending to device.
The transfer can be completed in single transfer or multiple
transfer based on data formatting.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-14 14:03:32 -08:00
Laxman Dewangan c915719841 regmap: Support for caching in reg_raw_write()
Adding support for caching of data into the
non-volatile register from the call of reg_raw_write().

This will allow the larger block of data write into multiple
register without worrying whether register is cached or not
through reg_raw_write().

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-11 23:03:45 +00:00
Axel Lin 2a14d7d9b7 regmap: Fix kcalloc parameters swapped
The first parameter should be "number of elements" and the second parameter
should be "element size".

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-10 11:46:14 +00:00
Mark Brown 028a01e601 regmap: Add debugfs information for the cache status
Show all the cache status flags in debugfs if we have a cache.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-06 19:24:46 +00:00
Mark Brown 847fb6fdf5 regmap: Don't use bitfields for booleans
This was a cut'n'paste from some older code.

Since we're about to add debugfs support don't do the obvious thing and
use bool, use u32 instead (which debugfs has been using since time
immemorial).

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-06 19:24:35 +00:00
Axel Lin aa795d1292 regmap: Remove incorrect unreachable comment in regcache_set_val()
regcache_set_val() returns false if cache[idx] != val.
Thus it actually is not unreachable.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-31 11:25:08 +00:00
Mark Brown c0eb46766d regmap: Implement managed regmap_init()
Save error handling and unwinding code in drivers by providing managed
versions of the regmap init functions, simplifying usage.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-30 21:06:43 +00:00
Wolfram Sang 4191f19792 regmap: if format_write is used, declare all registers as "unreadable"
Using .format_write means, we have a custom function to write to the
chip, but not to read back. Also, mark registers as "not precious" and
"not volatile" which is implicit because we cannot read them. Make those
functions use 'regmap_readable' to reuse the checks done there.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-30 16:23:11 +00:00
Wolfram Sang c212acccc3 regmap: Properly round reg_bytes and val_bytes
For the upcoming 2/6-format, we don't see debugfs output otherwise,
since the current division results in 0. I'd think 10/14 is broken
currently, too.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-29 21:42:40 +00:00
Wolfram Sang 9aa507505c regmap: Add support for 2/6 register formating
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-27 16:26:03 +00:00
Mark Brown a24f64a648 regmap: Reset device debugfs when reinitialising the cache
Most of the data exposed via debugfs is for or from the cache so reset
all the debugfs configuration to make sure everything is up to date with
the latest configuration, especially if we're changing cache type.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-26 18:34:49 +00:00
Mark Brown 8a892d6996 regmap: Bypass the cache when applying patches
Otherwise any patch that affects a register which is writable may trash
cached values.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-25 21:22:05 +00:00
Mark Brown d9db762708 regmap: Skip patch application when the cache is not dirty on sync
On the basis that if we don't actually need to resync the cache then the
patches are probably also already applied.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-25 21:21:56 +00:00
Mark Brown 7e53b195e4 regmap: Unexport regcache_write() and regcache_read()
They have no current users which is fortunate as they don't take the lock
and therefore aren't safe to use externally. We'll need to add new
operations if direct cache access is needed.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-25 21:20:49 +00:00
Mark Brown 22f0d90a34 regmap: Support register patch sets
Device manufacturers frequently provide register sequences, usually not
fully documented, to be run at startup in order to provide better defaults
for devices (for example, improving performance in the light of silicon
evaluation). Support such updates by allowing drivers to register update
sets with the core. These updates will be written to the device immediately
and will also be rewritten when the cache is synced.

The assumption is that the reason for resyncing the cache will always be
that the device has been powered off. If this turns out to not be the case
then a separate operation can be provided.

Currently the implementation only allows a single set of updates to be
specified for a device, this could be extended in future.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-23 14:01:18 +00:00
Mark Brown 421e8d2de3 regmap: Reset cache status when reinitialsing the cache
When we reinitialise the cache make sure that we reset the cache access
flags, ensuring that the reinitialised cache is in the default state
which is what callers would and do expect given the function name.

This is particularly likely to cause issues in systems where there was no
cache previously as those systems have cache bypass enabled, as for the
wm8994 driver where this was noticed.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-20 13:49:30 +00:00
Mark Brown 82159ba8e6 regmap: Add support for padding between register and address
Some devices, especially those with high speed control interfaces, require
padding between the register and the data. Support this in the regmap API
by providing a pad_bits configuration parameter.

Only devices with integer byte counts are supported.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-01-20 12:15:39 +00:00
Mark Brown 681ba97d9f Merge branch 'regmap/irq' into regmap-next 2011-12-05 16:21:05 +00:00
Mark Brown 209a600623 regmap: Add irq_base accessor to regmap_irq
Allows devices to discover their own interrupt without having to remember
it themselves.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-12-05 16:13:31 +00:00
Mark Brown 8569d023a0 Merge branch 'topic/cache' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into regmap-next 2011-12-05 13:18:50 +00:00
Mark Brown bf31517335 regmap: Allow drivers to reinitialise the register cache at runtime
Sometimes the register map information may change in ways that drivers can
discover at runtime. For example, new revisions of a device may add new
registers. Support runtime discovery by drivers by allowing the register
cache to be reinitialised with a new function regmap_reinit_cache() which
discards the existing cache and creates a new one.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-12-05 13:17:36 +00:00
Mark Brown bc7ee55633 regmap: Add trace event for successful cache reads
Currently we only trace physical reads, there's no instrumentation if
the read is satisfied from cache.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-30 20:51:09 +00:00
Mark Brown 018690d33e regmap: Allow regmap_update_bits() users to detect changes
Some users of regmap_update_bits() would like to be able to tell their
users if they actually did an update so provide a variant which also
returns a flag indicating if an update took place. We could return a
tristate in the return value of regmap_update_bits() but this makes the
API more cumbersome to use and doesn't fit with the general zero for
success idiom we have.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-29 20:15:50 +00:00
Mark Brown c86845dc7b Merge remote-tracking branch 'regmap/topic/irq' into regmap-next 2011-11-28 18:52:24 +00:00
Mark Brown d23511f959 regmap: Report if we actually handled an interrupt in regmap-irq
While the IRQ core doesn't currently support shared threaded interrupts
that's no reason for drivers not to do their bit and report IRQ_NONE when
they don't get an interrupt. This allows the core spurious/wedget interrupt
detection support to do its thing.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-28 18:51:57 +00:00
Mark Brown cce585ce1e regmap: Fix rbtreee build when not using debugfs
The debugfs functions don't stub themselves out quite so well as might
be desirable so provide functions which do do this stubbing.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-22 11:43:01 +00:00
Mark Brown bad2ab4b6d regmap: Provide debugfs dump of the rbtree cache data
Show the register ranges we have in each rbtree node in debugfs, plus
some statistics on how big each node is and the total number of nodes.
It may also be worth collecting data on the ranges of dirty registers
to see if there's much mileage in trying to coalesce writes on sync.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:50:10 +00:00
Mark Brown 052d2cd123 regmap: Do debugfs init before cache init
This allows caches to add custom debugfs files.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:48:26 +00:00
Mark Brown d91e8db2c3 regmap: Suppress noop writes in regmap_update_bits()
If the new register value is identical to the original one then suppress
the write to the hardware in regmap_update_bits(), saving some I/O cost.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-20 20:56:38 +00:00
Mark Brown 4c69166458 regmap: Remove indexed cache type
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 <broonie@opensource.wolfsonmicro.com>
2011-11-20 20:56:34 +00:00
Lars-Peter Clausen b44d48c1cc regmap: Drop check whether a register is readable in regcache_read
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 <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-17 16:51:27 +00:00
Lars-Peter Clausen 064d4db11e regmap: Properly round cache_word_size
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 <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-17 16:51:23 +00:00
Lars-Peter Clausen 7e5ec63ef5 regmap: Add support for 10/14 register formating
This patch adds support for 10 bits register, 14 bits value type register
formating. This is for example used by the Analog Devices AD5380.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-16 17:34:53 +00:00
Lars-Peter Clausen 19254411db regmap: Try cached read before checking if a hardware read is possible
For some register format types we do not provide a parse_val so we can not do a
hardware read. But a cached read is still possible, so try to read from the
cache first, before checking whether a hardware read is possible. Otherwise the
cache becomes pretty useless for these register types.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-16 17:34:53 +00:00
Lars-Peter Clausen 720e4616e8 regmap: Make reg_config reg_defaults const
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 <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-16 17:34:53 +00:00
Lars-Peter Clausen e5e3b8abed regmap: Move initialization of regcache related fields to regcache_init
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 <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-16 17:34:53 +00:00
Lars-Peter Clausen c2b1ecd13c regmap: Do not call regcache_exit from regcache_lzo_init error path
Calling regcache_exit from regcache_lzo_init is first of all a layering
violation and secondly will cause double frees. regcache_exit will free buffers
allocated by the core, but the core will also free the same buffers when the
cacheops init callback returns an error. Thus we end up with a double free.
Fix this by not calling regcache_exit but only free those buffers which, have
been allocated in this function.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-15 19:22:59 +00:00
Lars-Peter Clausen 462a185c5c regmap: Do not call regcache_exit from regcache_rbtree_init error path
Calling regcache_exit from regcache_rbtree_init is first of all a layering
violation and secondly will cause double frees. regcache_exit will free buffers
allocated by the core, but the core will also free the same buffers when the
cacheops init callback returns an error. Thus we end up with a double free.
Fix this by not calling regcache_exit but only free those buffers which, have
been allocated in this function.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-15 19:22:59 +00:00
Lars-Peter Clausen bd061c78ca regmap: Fix memory leak in regcache_init error path
Make sure all allocated memory gets freed again in case initializing the cache
failed.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-14 21:46:25 +00:00
Lars-Peter Clausen 021cd616de regmap: Fix memory leak in regcache_hw_init error path
Make sure reg_defaults_raw gets freed in case of an error.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-14 21:46:09 +00:00
Lars-Peter Clausen abbb18fb4a regmap: return ERR_PTR instead of NULL in regmap_init
The regmap_init documentation states that it will either return a pointer to a
valid regmap structure or a ERR_PTR in case of an error. Currently it returns a
NULL pointer in case no bus or no config was given. Since NULL is not a
ERR_PTR a caller might assume that it is a pointer to a valid regmap structure,
so return a ERR_PTR(-EINVAL) instead.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-14 21:44:45 +00:00
Lars-Peter Clausen 58072cbfc5 regmap: Fix memory leak in regmap_init error path
If regcache initialization fails regmap_init will currently exit without
freeing work_buf.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-10 17:41:20 +00:00
Lars-Peter Clausen c48a9d7492 regmap: Support some more block operations on cached devices
Commit 10a08d9f ("regmap: Support some block operations on cached devices")
allowed raw read operations without throwing a warning when using caches if
all registers are volatile. This patch does the same for raw write operations.

This is for example useful when loading a firmware in a predefined volatile
region on a chip where we otherwise want registers to be cached.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-09 00:56:52 +00:00
Lars-Peter Clausen 82cd9965c3 regmap: Add helper function for checking if a register range is volatile
We already have the same code for checking whether a register range is volatile
in two different places. Instead of duplicating it once more  add a small helper
function for checking whether a register range is voltaile.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-09 00:56:51 +00:00
Mark Brown 81bf58eb3c Merge branches 'regmap/irq' and 'regmap/cache' into regmap-next 2011-11-08 14:16:06 +00:00
Mark Brown 50b776fc71 regmap: Rename LZO cache type to compressed
Users probably don't care about the specific compression algorithm and
we might want to use a different algorithm (snappy being the one I'm
thinking of right now) so update the public interface to have a more
generic name.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-08 14:15:00 +00:00
Mark Brown 8ae0d7e8a9 regmap: Track if the register cache is dirty and suppress unneeded syncs
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 <broonie@opensource.wolfsonmicro.com>
2011-11-08 11:38:15 +00:00
Mark Brown b973aa3624 regmap: Fix typo in kerneldoc for regmap_update_bits()
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-08 11:32:55 +00:00
Mark Brown 7ea7580183 regmap: Fix word wrap in Makefile
80 columns FTW.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-08 11:32:31 +00:00
Mark Brown 82732bdd66 regmap: Prepare LZO cache for variable block sizes
Give regcache_lzo_block_count() a copy of the map so that when we decide
we want to make the LZO cache more controllable we can more easily do so.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-11-08 11:32:05 +00:00
Mark Brown f8beab2bb6 regmap: Add a reusable irq_chip for regmap based interrupt controllers
There seem to be lots of regmap-using devices with very similar interrupt
controllers with a small bank of interrupt registers and mask registers
with an interrupt per bit. This won't cover everything but it's a good
start.

Each chip supplies a base for the status registers, a base for the mask
registers, an optional base for writing acknowledgements (which may be the
same as the status registers) and an array of bits within each of these
register banks which indicate the interrupt.

There is an assumption that the bit for each interrupt will be the same
in each of the register bank.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-08 11:29:48 +00:00
Paul Gortmaker 1b6bc32f0a drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.
Most of these files were implicitly getting EXPORT_SYMBOL via
device.h which was including module.h, but that path will be broken
soon.

[ with input from Stephen Rothwell <sfr@canb.auug.org.au> ]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:38 -04:00
Linus Torvalds 4e7e2a2008 Merge branch 'for-linus' of git://opensource.wolfsonmicro.com/regmap
* 'for-linus' of git://opensource.wolfsonmicro.com/regmap: (62 commits)
  mfd: Enable rbtree cache for wm831x devices
  regmap: Support some block operations on cached devices
  regmap: Allow caches for devices with no defaults
  regmap: Ensure rbtree syncs registers set to zero properly
  regmap: Allow rbtree to cache zero default values
  regmap: Warn on raw I/O as well as bulk reads that bypass cache
  regmap: Return a sensible error code if we fail to read the cache
  regmap: Use bsearch() to search the register defaults
  regmap: Fix doc comment
  regmap: Optimize the lookup path to use binary search
  regmap: Ensure we scream if we enable cache bypass/only at the same time
  regmap: Implement regcache_cache_bypass helper function
  regmap: Save/restore the bypass state upon syncing
  regmap: Lock the sync path, ensure we use the lockless _regmap_write()
  regmap: Fix apostrophe usage
  regmap: Make _regmap_write() global
  regmap: Fix lock used for regcache_cache_only()
  regmap: Grab the lock in regcache_cache_only()
  regmap: Modify map->cache_bypass directly
  regmap: Fix regcache_sync generic implementation
  ...
2011-10-25 13:57:45 +02:00
Mark Brown de2d808f4d regmap: Support some block operations on cached devices
Support raw reads if all the registers being read are volatile, the cache
will have no impact for tem.

Support bulk reads either directly (if all the registers are volatile) or
by falling back to iterating over single register reads otherwise.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-13 11:41:54 +01:00
Mark Brown 8528bdd450 regmap: Allow caches for devices with no defaults
We only really need the defaults in order to cut down the number of
registers we sync and to satisfy reads while the device is powered off
but not all devices are going to need to do that (always on devices like
PMICs being the prime example) so don't require those devices to supply
a default.  Instead only try to fall back to hardware defaults if the
driver told us to.

Devices using LZO won't be able to instantiate with this, that will require
some updates in the LZO code to handle this case.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-10-10 11:55:32 +01:00
Mark Brown b03622a80d regmap: Ensure rbtree syncs registers set to zero properly
Simplify the check for registers set at their default value by avoiding
picking a default value in the case where we don't have one. Instead we
only compare the current value to the current value when we looked one
up. This fixes the case where we don't have a default stored but the value
was set to zero when that isn't the chip default.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-10-10 10:26:48 +01:00
Mark Brown e42c5a9a42 regmap: Allow rbtree to cache zero default values
Ensure that when we start up in cache only mode we can store defaults of
zero, otherwise if the hardware is unavailable we won't be able to read.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-10-10 10:25:00 +01:00
Mark Brown 04e016adca regmap: Warn on raw I/O as well as bulk reads that bypass cache
As with the bulk reads we really should be able to make these play
nicely with the cache but warn for now.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-10-10 10:24:33 +01:00
Mark Brown 6e6ace00a0 regmap: Return a sensible error code if we fail to read the cache
If a register isn't cached then let callers know that so they can fall
back or error handle appropriately.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-10-10 10:24:03 +01:00
Mark Brown f094fea68f regmap: Use bsearch() to search the register defaults
Rather than open coding a binary search use the standard bsearch() using
the comparison function we're already using for sort() on insert. This
fixes a lockup I was observing due to iterating on min <= max rather
than min < max when we fail to look up.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-10-09 12:36:56 +01:00
Dimitris Papastamos 0eef6b0415 regmap: Fix doc comment
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-03 11:50:53 +01:00
Dimitris Papastamos c08604b8ae regmap: Optimize the lookup path to use binary search
Since there are more lookups than insertions in a typical
scenario, optimize the linear search into a binary search.  For
this to work, we need to keep reg_defaults sorted upon
insertions, for now be lazy and use sort().

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-03 11:50:53 +01:00
Dimitris Papastamos ac77a765cb regmap: Ensure we scream if we enable cache bypass/only at the same time
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-30 13:57:47 +01:00
Dimitris Papastamos 6eb0f5e015 regmap: Implement regcache_cache_bypass helper function
Ensure we've got a function so users can enable/disable the
cache bypass option.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-30 13:57:47 +01:00
Dimitris Papastamos beb1a10f21 regmap: Save/restore the bypass state upon syncing
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-30 13:57:47 +01:00
Dimitris Papastamos 13753a9088 regmap: Lock the sync path, ensure we use the lockless _regmap_write()
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-30 13:57:47 +01:00
Mark Brown 5fcd256076 regmap: Fix apostrophe usage
An apostrophe does not mean "look out, here comes an s!".

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-30 11:20:14 +01:00
Dimitris Papastamos 4d2dc09538 regmap: Make _regmap_write() global
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-29 11:19:45 +01:00
Mark Brown 2cd148f159 regmap: Fix lock used for regcache_cache_only()
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-29 10:40:55 +01:00
Dimitris Papastamos 38f6916976 regmap: Grab the lock in regcache_cache_only()
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-28 13:57:36 +01:00
Dimitris Papastamos ec8a365fe6 regmap: Modify map->cache_bypass directly
In preperation for the upcoming patches, modify map->cache_bypass
directly.  The helper functions will grab an exclusive lock.  Because
we'll have acquired the same lock we need to avoid a deadlock.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-28 13:56:39 +01:00
Dimitris Papastamos a40c282362 regmap: Fix regcache_sync generic implementation
We want to use regmap_write() to actually write anything
to the HW.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-28 13:56:39 +01:00
Lars-Peter Clausen 3405addd22 regmap: rbtree-cache: Move cached rbnode handling into lookup function
Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows
us to remove of some duplicated code sections in regcache_rbtree_read and
regcache_rbtree_write.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-28 13:18:22 +01:00
Lars-Peter Clausen c5713004b3 regmap: regcache_rbtree_{set,get}_register: Use regcache_{set,get}_val
Use regcache_{set,get}_val in regcache_rbtree_{set,get}_register instead of
re-implementing its functionality.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-28 13:18:11 +01:00
Dimitris Papastamos 954757d767 regmap: Implement generic syncing functionality
In the absence of a sync callback, do it manually.  This of course
can't take advantange of the specific optimizations of each
cache type but it will do well enough in most cases.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 20:06:38 +01:00
Dimitris Papastamos dfdc4448e0 regmap: Fix signed/unsigned comparison
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 13:27:09 +01:00
Dimitris Papastamos 25ed1156dd regmap: Remove redundant member `word_size' from regcache_rbtree_node
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 13:27:09 +01:00
Mark Brown 92afb286d7 regmap: Allow drivers to control cache_only flag
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:37 +01:00
Mark Brown e7a6db30df regmap: A cache type of _NONE behaves like a bypassed cache
Avoid extra special casing by setting the cache_bypass flag when we're
not caching.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:36 +01:00
Dimitris Papastamos 5d1729e7f0 regmap: Incorporate the regcache core into regmap
This patch incorporates the regcache core code into regmap.  All previous
patches have been no-ops essentially up to this point.

The bulk read operation is not supported by regcache at the moment.  This
will be implemented incrementally.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Tested-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:35 +01:00
Dimitris Papastamos 5936008901 regmap: Add the regcache_sync trace event
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:34 +01:00
Dimitris Papastamos 2cbbb579bc regmap: Add the LZO cache support
This patch adds support for LZO compression when storing the register
cache.

For a typical device whose register map would normally occupy 25kB or 50kB
by using the LZO compression technique, one can get down to ~5-7kB.  There
might be a performance penalty associated with each individual read/write
due to decompressing/compressing the underlying cache, however that should not
be noticeable.  These memory benefits depend on whether the target architecture
can get rid of the memory occupied by the original register defaults cache
which is marked as __devinitconst.  Nevertheless there will be some memory
gain even if the target architecture can't get rid of the original register
map, this should be around ~30-32kB instead of 50kB.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:33 +01:00
Dimitris Papastamos 28644c809f regmap: Add the rbtree cache support
This patch adds support for the rbtree cache compression type.

Each rbnode manages a variable length block of registers.  There can be no
two nodes with overlapping blocks.  Each block has a base register and a
currently top register, all the other registers, if any, lie in between these
two and in ascending order.

The reasoning behind the construction of this rbtree is simple.  In the
snd_soc_rbtree_cache_init() function, we iterate over the register defaults
provided by the regcache core.  For each register value that is non-zero we
insert it in the rbtree.  In order to determine in which rbnode we need
to add the register, we first look if there is another register already
added that is adjacent to the one we are about to add.  If that is the case
we append it in that rbnode block, otherwise we create a new rbnode
with a single register in its block and add it to the tree.

There are various optimizations across the implementation to speed up lookups
by caching the most recently used rbnode.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Tested-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:33 +01:00
Dimitris Papastamos 195af65ca9 regmap: Add the indexed cache support
This is the simplest form of a cache available in regcache.  Any
registers whose default value is 0 are ignored.  If any of those
registers are modified in the future, they will be placed in the
cache on demand.  The cache layout is essentially using the provided
register defaults by the regcache core directly and does not re-map
it to another representation.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:32 +01:00
Dimitris Papastamos 9fabe24e9b regmap: Introduce caching support
This patch introduces caching support for regmap.  The regcache API
has evolved essentially out of ASoC soc-cache so most of the actual
caching types (except LZO) have been tested in the past.

The purpose of regcache is to optimize in time and space the handling
of register caches.  Time optimization is achieved by not having to go
over a slow bus like I2C to read the value of a register, instead it is
cached locally in memory and can be retrieved faster.  Regarding space
optimization, some of the cache types are better at packing the caches,
for e.g. the rbtree and the LZO caches.  By doing this the sacrifice in
time still wins over doing I2C transactions.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Tested-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 19:06:31 +01:00
Linus Torvalds 9ba365438a Merge branch 'for-linus' of git://opensource.wolfsonmicro.com/regmap
* 'for-linus' of git://opensource.wolfsonmicro.com/regmap:
  regmap: Remove bitrotted module_put()s
2011-09-08 16:47:52 -07:00
Lars-Peter Clausen bbcf61ca8d regmap: Make debugfs stubs static inline
Make the debugfs stubs static inline to avoid future compilation issues due to
duplicated symbols when CONFIG_DEBUG_FS=n once internal.h is included by
multiple source files.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-05 15:00:08 -07:00
Lars-Peter Clausen 6f306441e9 regmap: Add support for device specific write and read flag masks.
Some buses like SPI have no standard notation of read or write operations.
The general scheme here is to set or clear specific bits in the register
address to indicate whether the operation is a read or write. We already
support having a read flag mask per bus, but as there is no standard
the bits which need to be set or cleared differ between devices and vendors,
thus we need a mechanism to specify them per device.

This patch adds two new entries to the regmap_config struct, read_flag_mask and
write_flag_mask. These will be or'ed onto the top byte when doing a read or
write operation. If both masks are empty the device will fallback to the
regmap_bus masks.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-05 14:55:57 -07:00
Mark Brown d813ae9a10 regmap: Include the last register in debugfs output
Off by one in the array iteration.

Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-05 10:58:31 -07:00
Mark Brown 5b457e3910 regmap: Remove redundant owner field from the bus type struct
No longer used as users link directly with the bus types so the core
module infrastructure does refcounting for us.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-05 10:57:04 -07:00
Mark Brown a7ace561f1 Merge branch 'regmap-linus' into regmap-next 2011-09-05 10:56:57 -07:00
Mark Brown 5204f5e3f5 regmap: Remove bitrotted module_put()s
The conversion to per bus type registration functions means we don't need
to do module_get()s to hold the bus types in memory (their users will link
to them) so we removed all those calls. This left module_put() calls in
the cleanup paths which aren't needed and which cause unbalanced puts if
we ever try to unload anything.

Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-05 10:55:58 -07:00
Stephen Rothwell b5ddbf465f regmap: using module facilities requires module.h
Commit b33f9cbd67 ("regmap: Specify a module license") added a
MODULES_LICENSE to this file without adding an include of module.h.

module.h should have been included anyway, since this file has
EXPORT_SYMBOLs as well.  With the pending module.h split up, this would
probably have caused build problems.

Cc: Stephen Warren <swarren@nvidia.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-15 19:28:17 -07:00
Mark Brown 449e38427f regmap: Provide access information via debugfs
Let userspace know what the access map for the device is. This is helpful
for verifying that the access map is correctly configured and could also
be useful for programs that try to work with the data. File format is:

register: R W V P

where R, W, V and P are 'y' or 'n' showing readable, writable, volatile
and precious respectively.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-14 19:51:16 +09:00
Mark Brown 21f5554456 regmap: Share some of the debugfs infrastructure ready for more files
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-14 19:51:14 +09:00
Mark Brown 8de2f081ef regmap: Add functions to check for access on registers
We're going to be using these in quite a few places so factor out the
readable/writable/volatile/precious checks.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-14 19:51:11 +09:00
Mark Brown 13c54137f7 Merge branch 'regmap-linus' into regmap-next 2011-08-12 10:43:15 +09:00
Stephen Warren b33f9cbd67 regmap: Specify a module license
CONFIG_REGMAP_I2C/SPI are set to m when selected by a tristate config
option that's set to m. The regmap modules don't specify a license, so
fail to link to regmap_init at load time, since that is EXPORT_SYMBOL_GPL.
Fix this by specifying a license for the regmap modules.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-12 10:42:02 +09:00
Mark Brown 790923e56b regmap: Remove unused type and list fields from bus interface
We no longer enumerate the bus types, we rely on the driver telling us
this on init.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-10 00:26:38 +09:00
Mark Brown cb3c2dcfa3 regmap: Fix type of field width specifiers for x86_64
x86_64 size_t is not an int but the printf format specifier for size_t
should be an int.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
2011-08-10 00:26:38 +09:00
Mark Brown 2efe1642b7 regmap: Skip precious registers when dumping registers via debugfs
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:57:35 +09:00
Mark Brown 31244e396f regmap: Provide register map dump via debugfs
Copy over the read parts of the ASoC debugfs implementation into regmap,
allowing users to see what the register values the device has are at
runtime. The implementation, especially the support for seeking, is
mostly due to Dimitris Papastamos' work in ASoC.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:57:00 +09:00
Mark Brown 93de91245b regmap: Use a local header for API internals
Allowing the implementation to be multi-file.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:56:50 +09:00
Mark Brown 7330478127 regmap: Implement writable register checks
This is mainly intended to be used by devices which can dynamically
block register writes at runtime, for other devices there is usually
limited value.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:56:41 +09:00
Mark Brown fb2736bbae regmap: Add basic tracepoints
Trace single register reads and writes, plus start/stop tracepoints for
the actual I/O to see where we're spending time. This makes it easy to
have always on logging without overwhelming the logs and also lets us take
advantage of all the context and time information that the trace subsystem
collects for us.

We don't currently trace register values for bulk operations as this would
add complexity and overhead parsing the cooked data that's being worked
with.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:56:16 +09:00
Mark Brown 555fedacc3 Merge branches 'regmap-linus' and 'regmap-interface' into regmap-next 2011-08-08 15:55:53 +09:00
Mark Brown 2547e201b3 regmap: Just send the buffer directly for single register writes
When doing a single register write we use work_buf for both the register
and the value with the buffer formatted for sending directly to the device
so we can just do a write() directly. This saves allocating a temporary
buffer if we can't do gather writes and is likely to be faster than doing
a gather write.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:52:25 +09:00
Mark Brown 2e2ae66df3 regmap: Allow devices to specify which registers are accessible
This is currently unused but we need to know which registers exist and
their properties in order to implement diagnostics like register map
dumps and the cache features.

We use callbacks partly because properties can vary at runtime (eg, through
access locks on registers) and partly because big switch statements are a
good compromise between readable code and small data size for providing
information on big register maps.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-08-08 15:47:00 +09:00
Mark Brown 40c5cc2639 regmap: Fix bulk reads
We should be reading the number of bytes we were asked for, not the size
of a single register.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-07-24 22:44:51 +01:00
Mark Brown a676f08306 regmap: Add SPI bus support
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-23 07:56:59 +01:00
Mark Brown 9943fa300a regmap: Add I2C bus support
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-23 07:56:39 +01:00
Mark Brown b83a313bf2 regmap: Add generic non-memory mapped register access API
There are many places in the tree where we implement register access for
devices on non-memory mapped buses, especially I2C and SPI. Since hardware
designers seem to have settled on a relatively consistent set of register
interfaces this can be effectively factored out into shared code.  There
are a standard set of formats for marshalling data for exchange with the
device, with the actual I/O mechanisms generally being simple byte
streams.

We create an abstraction for marshaling data into formats which can be
sent on the control interfaces, and create a standard method for
plugging in actual transport underneath that.

This is mostly a refactoring and renaming of the bottom level of the
existing code for sharing register I/O which we have in ASoC. A
subsequent patch in this series converts ASoC to use this.  The main
difference in interface is that reads return values by writing to a
location provided by a pointer rather than in the return value, ensuring
we can use the full range of the type for register data.  We also use
unsigned types rather than ints for the same reason.

As some of the devices can have very large register maps the existing
ASoC code also contains infrastructure for managing register caches.
This cache work will be moved over in a future stage to allow for
separate review, the current patch only deals with the physical I/O.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-23 07:56:03 +01:00