Commit Graph

17 Commits

Author SHA1 Message Date
Julia Lawall 9c2e5cb38d regmap: constify regmap_bus structures
These regmap_bus structures are only passed as the second argument to
__devm_regmap_init or __regmap_init, both of which are const, so the
regmap_bus structures can be const too.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-14 17:36:29 +01:00
Nicolas Boichat 1ed8111443 regmap: Move documentation to regmap.h
Init functions defined in regmap*.c files are now prefixed with
__, take lockdep key and class parameters, and should not be
called directly: move the documentation to regmap.h, where the
macros are defined.

Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-08-11 17:21:44 +01:00
Nicolas Boichat 3cfe7a74d4 regmap: Use different lockdep class for each regmap init call
Lockdep validator complains about recursive locking and deadlock
when two different regmap instances are called in a nested order.
That happens anytime a regmap read/write call needs to access
another regmap.

This is because, for performance reason, lockdep groups all locks
initialized by the same mutex_init() in the same lock class.
Therefore all regmap mutexes are in the same lock class, leading
to lockdep "nested locking" warnings if a regmap accesses another
regmap.

In general, it is impossible to establish in advance the hierarchy
of regmaps, so we make sure that each regmap init call initializes
its own static lock_class_key. This is done by wrapping all
regmap_init calls into macros.

This also allows us to give meaningful names to the lock_class_key.
For example, in rt5677 case, we have in /proc/lockdep_chains:
irq_context: 0
[ffffffc0018d2198] &dev->mutex
[ffffffc0018d2198] &dev->mutex
[ffffffc001bd7f60] rt5677:5104:(&rt5677_regmap)->_lock
[ffffffc001bd7f58] rt5677:5096:(&rt5677_regmap_physical)->_lock
[ffffffc001b95448] &(&base->lock)->rlock

The above would have resulted in a lockdep recursive warning
previously. This is not the case anymore as the lockdep validator
now clearly identifies the 2 regmaps as separate.

Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-08-07 14:50:59 +01:00
Xiubo Li d647c19951 regmap: add DT endianness binding support.
For many drivers which will support rich endianness of Devices
need define DT properties by itself with the binding support.

The endianness using regmap:
Index      Device     Properties if needs bytes-swap,
                      or just ignore it
-------------------------------------------------------------
1          BE         'big-endian'
2          LE         'little-endian'

The properties include all the register values and the buffers.
And these properties are very usful for the MMIO devices:

Such as: a memory-mapped device, on one SoC is in BE mode, while
in another SoC will be in LE mode, and the CPU will always in LE
mode.

For the first case, we must use cpu_to_be32/be32_to_cpu for
32-bit registers accessing, so the 'big-endian' property is needed.

For the second case, we can just ignore the bytes-swap
functions like cpu_to_le32/le32_to_cpu, so the 'little-endian'
property could be abscent.

And vice versa...

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-08-16 16:56:23 -05:00
Paul Gortmaker 4272b9611c drivers/base: delete non-required instances of include <linux/init.h>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>.  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Cc: Len Brown <len.brown@intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-14 14:31:37 -08:00
Mark Brown cd1b9dd022 regmap: spi: Handle async writes of only one buffer
If the value is zero then assume it has been included in the register data
and don't send anything, minimising the number of interactions with the
hardware.

Signed-off-by: Mark Brown <broonie@linaro.org>
2013-10-14 22:09:26 +01:00
Mark Brown 95601d65a1 regmap: spi: Handle allocation failures gracefully
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-05 14:14:32 +00:00
Mark Brown e0356dfe98 regmap: spi: Support asynchronous I/O for SPI
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-01-29 12:16:21 +08:00
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
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
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 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
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 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 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