Commit graph

80 commits

Author SHA1 Message Date
Dimitris Papastamos
4d879514e7 regmap: Don't lock in regmap_reinit_cache()
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: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-08-04 11:07:57 +01:00
Mark Brown
38e23194e1 Merge branches 'regmap-core', 'regmap-irq' and 'regmap-page' into regmap-next
Conflicts (trivial context stuff):
	drivers/base/regmap/regmap.c
	include/linux/regmap.h
2012-07-22 19:26:07 +01:00
Mark Brown
1044c180de regmap: Add hook for printk logging for debugging during early init
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: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-07-06 14:16:16 +01:00
Krystian Garbaciak
632a5b01db regmap: Fix work_buf switching for page update during virtual range access.
After page update, orginal work_buf has to be restored regardless of
the result.

Signed-off-by: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-19 10:42:56 +01:00
Krystian Garbaciak
6863ca6227 regmap: Add support for register indirect addressing.
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: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-17 21:34:18 +01:00
Krystian Garbaciak
fc3ebd788e regmap: Move lock out from internal function _regmap_update_bits().
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: Krystian Garbaciak <krystian.garbaciak@diasemi.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-17 21:30:39 +01:00
Mark Brown
752a6a5f84 regmap: Export regmap_reinit_cache()
It's supposed to be there for drivers.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-08 05:57:21 +08:00
Fabio Estevam
5494a98f45 regmap: Fix the size calculation for map->format.buf_size
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: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03 13:14:01 +01:00
Stephen Warren
bfaa25f334 regmap: clean up debugfs if regmap_init fails
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: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03 13:13:38 +01:00
Stephen Warren
141eba2e00 regmap: allow busses to request formatting with specific endianness
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: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-06-03 13:11:43 +01:00
Mark Brown
06e65cb322 Merge branches 'regmap-core', 'regmap-stride', 'regmap-mmio' and 'regmap-irq' into regmap-next 2012-05-13 19:20:47 +01:00
Mark Brown
25061d2857 regmap: Last minute bug fix for 3.4
This is a last minute bug fix that was only just noticed since the code
 path that's being exercised here is one that is fairly rarely used.  The
 changelog for the change itself is extremely clear and the code itself
 is obvious to inspection so should be pretty safe.
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Merge tag 'regmap-3.4' into regmap-stride

regmap: Last minute bug fix for 3.4

This is a last minute bug fix that was only just noticed since the code
path that's being exercised here is one that is fairly rarely used.  The
changelog for the change itself is extremely clear and the code itself
is obvious to inspection so should be pretty safe.

Conflicts:
	drivers/base/regmap/regmap.c (overlap between the fix and stride code)
2012-05-12 13:06:08 +01:00
Laxman Dewangan
6560ffd1cc regmap: fix possible memory corruption in regmap_bulk_read()
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: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-05-09 15:44:11 +01:00
Mark Brown
72b39f6f2b regmap: Implement dev_get_regmap()
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: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-05-08 18:19:15 +01:00
Mark Brown
7a64761432 regmap: Devices using format_write don't support bulk operations
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: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-30 23:30:15 +01:00
Ashish Jangam
2e33caf16f regmap: Converts group operation into single read write operations
Some devices does not support bulk read and write operations, for them
we have series of single write and read operations.

Signed-off-by: Anthony Olech <Anthony.Olech@diasemi.com>
Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
[Fixed coding style, don't check use_single_rw before assign --broonie ]
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-30 23:29:56 +01:00
Mark Brown
f298536728 regmap: Cache single values read from the chip
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: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-30 22:57:10 +01:00
Stephen Warren
f01ee60fff regmap: implement register striding
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: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-10 11:01:18 +01:00
Mark Brown
c0cc6fe1d0 Merge branches 'regmap-core', 'regmap-mmio' and 'regmap-naming' into regmap-stride 2012-04-10 11:01:07 +01:00
Stephen Warren
d3c242e1f2 regmap: allow regmap instances to be named
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: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-10 10:31:41 +01:00
Stephen Warren
851960ba7c regmap: validate regmap_raw_read/write val_len
val_len should be a multiple of val_bytes. If it's not, error out early.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-07 09:27:04 +01:00
Stephen Warren
bacdbe0773 regmap: introduce fast_io busses, and use a spinlock for them
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: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-06 10:47:34 +01:00
Stephen Warren
0135bbcc7a regmap: introduce explicit bus_context for bus callbacks
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: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-06 10:47:34 +01:00
Marc Reilly
d939fb9a78 regmap: Use pad_bits and reg_bits when determining register format.
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: Marc Reilly <marc@cpdesign.com.au>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-01 11:55:20 +01:00
Marc Reilly
ea279fc561 regmap: Add support for device with 24 data bits.
Add support for devices with 24 data bits.

Signed-off-by: Marc Reilly <marc@cpdesign.com.au>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-01 11:54:06 +01:00
Mark Brown
addfd8a09e Merge remote-tracking branch 'regmap/topic/bulk' into regmap-next 2012-03-14 13:15:48 +00:00
Mark Brown
eae4b51b21 Merge remote-tracking branch 'regmap/topic/introspection' into regmap-next
Simple add/add conflict:
	drivers/base/regmap/regmap.c
2012-03-14 13:15:03 +00:00
Mark Brown
7d9aca39dc Merge remote-tracking branch 'regmap/topic/drivers' into regmap-next
Resolved simple add/add conflicts:
	drivers/base/regmap/internal.h
	drivers/base/regmap/regmap.c
2012-03-14 13:13:25 +00:00
Mark Brown
e1c1c69c8f Merge remote-tracking branches 'regmap/topic/core' and 'regmap/topic/devm' into regmap-next 2012-03-14 13:12:33 +00:00
Stephen Warren
f5d6eba74b regmap: Fix future missing prototype of devres_alloc() and friends
[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: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-03-11 12:52:44 +00:00
Paul Gortmaker
19694b5ea1 regmap: delete unused module.h from drivers/base/regmap files
Remove unused module.h and/or replace with export.h
as required.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-03-01 11:10:35 +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
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
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
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
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
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