This makes things consistent with the rest of the API and is actually what
the documentation says. We don't currently have any in tree users so low
cost.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

When bus->fast_io is set, the locking here is done with spinlocks.
This is currently true for the regmap-mmio bus implementation.

While holding a spinlock we can't go to sleep, various operations
like removing the debugfs entries or re-initializing the cache will
sleep, therefore, shift the locking up to the user.
Signed-off-by: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Sometimes for failures during very early init the trace infrastructure
isn't available early enough to be used.  For this sort of problem
defining LOG_DEVICE will add printks for basic register I/O on a specific
device, allowing trace to be extracted when the trace system doesn't come
up early enough to work with.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

After page update, orginal work_buf has to be restored regardless of
the result.
Signed-off-by: NKrystian Garbaciak <krystian.garbaciak@diasemi.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Devices with register paging or indirectly accessed registers can configure
register mapping to map those on virtual address range. During access to
virtually mapped register range, indirect addressing is processed
automatically, in following steps:
  1. selector for page or indirect register is updated (when needed);
  2. register in data window is accessed.

Configuration should provide minimum and maximum register for virtual range,
details of selector field for page selection, minimum and maximum register of
data window for indirect access.

Virtual range registers are managed by cache as well as direct access
registers. In order to make indirect access more efficient, selector register
should be declared as non-volatile, if possible.

struct regmap_config is extended with the following:
struct regmap_range_cfg	*ranges;
unsigned int		n_ranges;

[Also reordered debugfs init to later on since the cleanup code was
conflicting with the new cleanup code for ranges anyway -- broonie]
Signed-off-by: NKrystian Garbaciak <krystian.garbaciak@diasemi.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Locks are moved to regmap_update_bits(), which allows to reenter internal
function _regmap_update_bits() from inside of regmap read/write routines.
Signed-off-by: NKrystian Garbaciak <krystian.garbaciak@diasemi.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

It's supposed to be there for drivers.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The word to be transmitted/received via regmap is composed by the following
parts:

config->reg_bits
config->val_bits
config->pad_bits

,so the total size should be calculated by summing up the number of bits of
each element and using a DIV_ROUND_UP to return the number of bytes.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

If debugfs isn't cleaned up, stale files will be left in the filesystem
which will cause an OOPS when accessed the first time, and hang the
accessing application when accessed again, presumably due to some lock
being left held.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Add a field to struct regmap_bus that allows bus drivers to request that
register addresses and values be formatted with a specific endianness.

The default endianness is unchanged from current operation: Big.

Implement native endian formatting/parsing for 16- and 32-bit values.
This will be enough to support regmap-mmio.c.
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The function regmap_bulk_read() calls the regmap_read() for
each register if set of register has volatile and cache is
enabled. In this case, last few register read makes the memory
corruption if the register size is not the size of unsigned int.
The regam_read() takes argument as unsigned int for returning
value and it update the value as
	*val = map->format.parse_val(map->work_buf);
This causes complete 4 bytes (size of unsigned int) to get written.
Now if client pass the memory pointer for value which is equal to the
required size of register count in regmap_bulk_read() then last few
register read actually update the memory beyond passed pointer size.

Avoid this by using local variable for read and then do memcpy()
for actual byte copy to passed pointer based on register size.

I allocated one pointer ptr and take first 16 bytes dump of that
pointer then call regmap_bulk_read() with pointer which is just
on top of this allocated pointer and register count of 128. Here
register size is 1 byte.
The memory trace of last 5 register read are as follows:

[    5.438589] regmap_bulk_read after regamp_read() for register 122
[    5.447421] 0xef993c20 0xef993c00 0x00000000 0x00000001
[    5.467535] regmap_bulk_read after regamp_read() for register 123
[    5.476374] 0xef993c20 0xef993c00 0x00000000 0x00000001
[    5.496425] regmap_bulk_read after regamp_read() for register 124
[    5.505260] 0xef993c20 0xef993c00 0x00000000 0x00000001
[    5.525372] regmap_bulk_read after regamp_read() for register 125
[    5.534205] 0xef993c00 0xef993c00 0x00000000 0x00000001
[    5.554258] regmap_bulk_read after regamp_read() for register 126
[    5.563100] 0xef990000 0xef993c00 0x00000000 0x00000001
[    5.554258] regmap_bulk_read after regamp_read() for register 127
[    5.587108] 0xef000000 0xef993c00 0x00000000 0x00000001

Here it is observed that the memory content at first word started changing
on last 3 regmap_read() and so corruption happened.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
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>

Set the use_single_rw flag for devices that use format_write() since
format_write() doesn't support any form of block operation.
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>

If we don't have a cached value for a register and we can cache it then
when we do a read a value we should add it to the cache to save rereading
it later on. Do this for single register reads, for block reads the code
would be a little more complex and this covers most practical usage.
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>

val_len should be a multiple of val_bytes. If it's not, error out early.
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>

This change combines any padding bits into the register address bits when
determining register format handlers to use the next byte-divisible
register size.
A reg_shift member is introduced to the regmap struct to enable fixup
of the reg format.
Format handlers now take an extra parameter specifying the number of
bits to shift the value by.
Signed-off-by: NMarc Reilly <marc@cpdesign.com.au>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Add support for devices with 24 data bits.
Signed-off-by: NMarc Reilly <marc@cpdesign.com.au>
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>

val_len should be a multiple of val_bytes. If it's not, error out early.
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>

This change combines any padding bits into the register address bits when
determining register format handlers to use the next byte-divisible
register size.
A reg_shift member is introduced to the regmap struct to enable fixup
of the reg format.
Format handlers now take an extra parameter specifying the number of
bits to shift the value by.
Signed-off-by: NMarc Reilly <marc@cpdesign.com.au>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Add support for devices with 24 data bits.
Signed-off-by: NMarc Reilly <marc@cpdesign.com.au>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

For files that are actively using linux/device.h, make sure
that they call it out.  This will allow us to clean up some
of the implicit uses of linux/device.h within include/*
without introducing build regressions.

Yes, this was created by "cheating" -- i.e. the headers were
cleaned up, and then the fallout was found and fixed, and then
the two commits were reordered.  This ensures we don't introduce
build regressions into the git history.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

[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>

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>

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>

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: NLaxman Dewangan <ldewangan@nvidia.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>