[Fix for breakage which will be introduced during the merge window via
header reworks in another tree, the regmap tree does include device.h
but Paul's tree breaks that.  Reworded subject to reflect -- broonie]

regmap.s uses devres_alloc() and others that are prototyped in device.h.
Include that to solve the following:

drivers/base/regmap/regmap.c: In function 'devm_regmap_init':
drivers/base/regmap/regmap.c:331:2: error: implicit declaration of function 'devres_alloc' [-Werror=implicit-function-declaration]
drivers/base/regmap/regmap.c:338:3: error: implicit declaration of function 'devres_add' [-Werror=implicit-function-declaration]
drivers/base/regmap/regmap.c:340:3: error: implicit declaration of function 'devres_free' [-Werror=implicit-function-declaration]
drivers/base/regmap/regmap.c: In function '_regmap_raw_write':
drivers/base/regmap/regmap.c:421:5: error: implicit declaration of function 'dev_err' [-Werror=implicit-function-declaration]
Signed-off-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Remove unused module.h and/or replace with export.h
as required.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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

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

The first parameter should be "number of elements" and the second parameter
should be "element size".
Signed-off-by: NAxel Lin <axel.lin@gmail.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>

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: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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: 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>

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: 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>

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: NLars-Peter Clausen <lars@metafoo.de>
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>

This allows caches to add custom debugfs files.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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

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

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

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

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

If regcache initialization fails regmap_init will currently exit without
freeing work_buf.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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

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: NLars-Peter Clausen <lars@metafoo.de>
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>

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

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

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

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

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: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Tested-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>

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: NJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

We're going to be using these in quite a few places so factor out the
readable/writable/volatile/precious checks.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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

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

Allowing the implementation to be multi-file.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

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

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

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