In some chips the IRQ status registers are not contiguous in the register
map but spaced at even spaces. This is an easy case to handle with minor
changes. It is assume for this purpose that the stride for status is
equal to the stride for mask/ack registers as well.
Signed-off-by: NGraeme Gregory <gg@slimlogic.co.uk>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

This gets us up to date with the recommended current kernel infrastructure
and should transparently give us device tree interrupt bindings for any
devices using the framework. If an explicit IRQ mapping is passed in then
a legacy interrupt range is created, otherwise a simple linear mapping is
used. Previously a mapping was mandatory so existing drivers should not
be affected.

A function regmap_irq_get_virq() is provided to allow drivers to map
individual IRQs which should be used in preference to the existing
regmap_irq_chip_get_base() which is only valid if a legacy IRQ range is
provided.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Use devres to implement dev_get_regmap(). This should mean that in almost
all cases devices wishing to take advantage of framework features based on
regmap shouldn't need to explicitly pass the regmap into the framework.
This simplifies device setup a bit.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Some devices does not support bulk read and write operations, for them
we have series of single write and read operations.
Signed-off-by: NAnthony Olech <Anthony.Olech@diasemi.com>
Signed-off-by: NAshish Jangam <ashish.jangam@kpitcummins.com>
[Fixed coding style, don't check use_single_rw before assign --broonie ]
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

regmap_config.reg_stride is introduced. All extant register addresses
are a multiple of this value. Users of serial-oriented regmap busses will
typically set this to 1. Users of the MMIO regmap bus will typically set
this based on the value size of their registers, in bytes, so 4 for a
32-bit register.

Throughout the regmap code, actual register addresses are used. Wherever
the register address is used to index some array of values, the address
is divided by the stride to determine the index, or vice-versa. Error-
checking is added to all entry-points for register address data to ensure
that register addresses actually satisfy the specified stride. The MMIO
bus ensures that the specified stride is large enough for the register
size.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Some devices have multiple separate register regions. Logically, one
regmap would be created per region. One issue that prevents this is that
each instance will attempt to create the same debugfs files. Avoid this
by allowing regmaps to be named, and use the name to construct the
debugfs directory name.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

This is a basic memory-mapped-IO bus for regmap. It has the following
features and limitations:

* Registers themselves may be 8, 16, 32, or 64-bit. 64-bit is only
  supported on 64-bit platforms.
* Register offsets are limited to precisely 32-bit.
* IO is performed using readl/writel, with no provision for using the
  __raw_readl or readl_relaxed variants.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Some bus types have very fast IO. For these, acquiring a mutex for every
IO operation is a significant overhead. Allow busses to indicate their IO
is fast, and enhance regmap to use a spinlock for those busses.

[Currently limited to native endian registers -- broonie]
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The only context needed by I2C and SPI bus definitions is the device
itself; this can be converted to an i2c_client or spi_device in order
to perform IO on the device. However, other bus types may need more
context in order to perform IO. Enable this by having regmap_init accept
a bus_context parameter, and pass this to all bus callbacks. The
existing callbacks simply pass the struct device here. Future bus types
may pass something else.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The <linux/device.h> header includes a lot of stuff, and
it in turn gets a lot of use just for the basic "struct device"
which appears so often.

Clean up the users as follows:

1) For those headers only needing "struct device" as a pointer
in fcn args, replace the include with exactly that.

2) For headers not really using anything from device.h, simply
delete the include altogether.

3) For headers relying on getting device.h implicitly before
being included themselves, now explicitly include device.h

4) For files in which doing #1 or #2 uncovers an implicit
dependency on some other header, fix by explicitly adding
the required header(s).

Any C files that were implicitly relying on device.h to be
present have already been dealt with in advance.

Total removals from #1 and #2: 51.  Total additions coming
from #3: 9.  Total other implicit dependencies from #4: 7.

As of 3.3-rc1, there were 110, so a net removal of 42 gives
about a 38% reduction in device.h presence in include/*
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Ensure we have a forward declaration of struct regmap that isn't just
the return value of regmap_init() and make the definition of the
register defaults available.
Reported-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Added on another branch.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Provide a regcache_sync_region() operation which allows drivers to
write only part of the cache back to the hardware. This is intended
for use in cases like power domains or DSP memories where part of the
device register map may be reset without fully resetting the device.

Fully supporting these devices is likely to require additional work to
make specific regions of the register map cache only while they are in
reset, but this is enough for most devices.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

Make life easier for subsystems which build infrastructure on top of the
regmap API by providing stub definitions for most of the API so that users
can at least build even if the regmap API is not enabled without having to
add ifdefs if they don't want to.

These stubs are not expected to be useful and should never actually get
called, they just exist so that we can link so there are WARN_ONCE()s in
the stubs.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Save error handling and unwinding code in drivers by providing managed
versions of the regmap init functions, simplifying usage.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

Allows devices to discover their own interrupt without having to remember
it themselves.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NMark Brown <broonie@opensource.wolfsonmicro.com>

The <linux/module.h> pretty much brings in the kitchen sink along
with it, so it should be avoided wherever reasonably possible in
terms of being included from other commonly used <linux/something.h>
files, as it results in a measureable increase on compile times.

The worst culprit was probably device.h since it is used everywhere.
This file also had an implicit dependency/usage of mutex.h which was
masked by module.h, and is also fixed here at the same time.

There are over a dozen other headers that simply declare the
struct instead of pulling in the whole file, so follow their lead
and simply make it a few more.

Most of the implicit dependencies on module.h being present by
these headers pulling it in have been now weeded out, so we can
finally make this change with hopefully minimal breakage.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Ensure we've got a function so users can enable/disable the
cache bypass option.
Signed-off-by: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Tested-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Tested-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Add the externally visible interface introduced by Lars-Peter's commit
6f3064 (regmap: Add support for device specific write and read flag
masks) separately in order to allow merge into other subsystems for
integration with drivers.  Drivers relying on this feature will not be
functional until they are merged with the implementation.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

No longer used as users link directly with the bus types so the core
module infrastructure does refcounting for us.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

It is useful for the register cache code to be able to specify the
default values for the device registers. The major use is when restoring
the register cache after suspend, knowing the register defaults allows
us to skip registers that are at their default values when we resume which
can be a substantial win on larger modern devices. For some devices
(mostly older ones) the hardware does not support readback so the only way we
can know the values is from code and so initializing the cache with default
values makes it much easier for drivers work with read/modify/write
updates.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

We no longer enumerate the bus types, we rely on the driver telling us
this on init.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>