The SoundWire 1.1 specification only allowed for reads and writes of
bytes. The SoundWire 1.2 specification adds a new capability to
transfer "Multi-Byte Quantities" (MBQ) across the bus. The transfers
still happens one-byte-at-a-time, but the update is atomic.
For example when writing a 16-bit volume, the first byte transferred
is only taken into account when the second byte is successfully
transferred.
The mechanism is symmetrical for read and writes:
- On a read, the address of the last byte to be read is modified by
setting the MBQ bit
- On a write, the address of all but the last byte to be written are
modified by setting the MBQ bit. The address for the last byte relies
on the MBQ bit being cleared.
The current definitions for MBQ-based controls in the SDCA draft
standard are limited to 16 bits for volumes, so for now this is the
only supported format. An update will be provided if and when support
for 24-bit and 32-bit values is specified by the SDCA standard.
One possible objection is that this code could have been handled with
regmap-sdw.c. However this is a new spec addition not handled by every
SoundWire 1.1 and non-SDCA device, so there's no reason to load code
that will never be used.
Also in practice it's extremely unlikely that CONFIG_REGMAP would not
be selected with CONFIG_REGMAP_MBQ selected. However there's no
functional dependency between the two modules so they can be selected
separately.
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20201103172226.4278-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch add support for regmap APIs that are intended to be used by
the drivers of some SPI slave chips which integrate the "SPI slave to
Avalon Master Bridge" (spi-avmm) IP.
The spi-avmm IP acts as a bridge to convert encoded streams of bytes
from the host to the chip's internal register read/write on Avalon bus.
The driver implements the register read/write operations for a generic
SPI master to access the sub devices behind spi-avmm bridge.
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Reviewed-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Link: https://lore.kernel.org/r/1597822497-25107-2-git-send-email-yilun.xu@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
CONFIG_REGMAP is not selected when no other serial bus is supported.
It's largely academic since CONFIG_I2C is usually selected e.g. by
DRM, but still this can break randconfig so let's be explicit.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200707202628.113142-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The existing code has a mixed select/depend usage which makes no sense.
config SOUNDWIRE_BUS
tristate
select REGMAP_SOUNDWIRE
config REGMAP_SOUNDWIRE
tristate
depends on SOUNDWIRE_BUS
Let's remove one layer of Kconfig definitions and align with the
solutions used by all other serial links.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190718230215.18675-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
REGMAP_SCCB is selected by ov772x and ov9650 drivers,
but CONFIG_REGMAP may not, so building will fails:
rivers/media/i2c/ov772x.c: In function ov772x_probe:
drivers/media/i2c/ov772x.c:1360:22: error: variable ov772x_regmap_config has initializer but incomplete type
static const struct regmap_config ov772x_regmap_config = {
^~~~~~~~~~~~~
drivers/media/i2c/ov772x.c:1361:4: error: const struct regmap_config has no member named reg_bits
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 5bbf32217b ("media: ov772x: use SCCB regmap")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190704093553.49904-1-yuehaibing@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Add basic support for i3c bus.
This is a simple implementation that only give support
for SDR Read and Write commands.
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This adds Serial Camera Control Bus (SCCB) support for regmap API that
is intended to be used by some of Omnivision sensor drivers.
The ov772x and ov9650 drivers are going to use this SCCB regmap API.
The ov772x driver was previously only worked with the i2c controller
drivers that support I2C_FUNC_PROTOCOL_MANGLING, because the ov772x
device doesn't support repeated starts. After commit 0b964d183c
("media: ov772x: allow i2c controllers without
I2C_FUNC_PROTOCOL_MANGLING"), reading ov772x register is replaced with
issuing two separated i2c messages in order to avoid repeated start.
Using this SCCB regmap hides the implementation detail.
The ov9650 driver also issues two separated i2c messages to read the
registers as the device doesn't support repeated start. So it can
make use of this SCCB regmap.
Cc: Mark Brown <broonie@kernel.org>
Cc: Peter Rosin <peda@axentia.se>
Cc: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Jacopo Mondi <jacopo+renesas@jmondi.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Here is the big pull request for char/misc drivers for 4.16-rc1.
There's a lot of stuff in here. Three new driver subsystems were added
for various types of hardware busses:
- siox
- slimbus
- soundwire
as well as a new vboxguest subsystem for the VirtualBox hypervisor
drivers.
There's also big updates from the FPGA subsystem, lots of Android binder
fixes, the usual handful of hyper-v updates, and lots of other smaller
driver updates.
All of these have been in linux-next for a long time, with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big pull request for char/misc drivers for 4.16-rc1.
There's a lot of stuff in here. Three new driver subsystems were added
for various types of hardware busses:
- siox
- slimbus
- soundwire
as well as a new vboxguest subsystem for the VirtualBox hypervisor
drivers.
There's also big updates from the FPGA subsystem, lots of Android
binder fixes, the usual handful of hyper-v updates, and lots of other
smaller driver updates.
All of these have been in linux-next for a long time, with no reported
issues"
* tag 'char-misc-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (155 commits)
char: lp: use true or false for boolean values
android: binder: use VM_ALLOC to get vm area
android: binder: Use true and false for boolean values
lkdtm: fix handle_irq_event symbol for INT_HW_IRQ_EN
EISA: Delete error message for a failed memory allocation in eisa_probe()
EISA: Whitespace cleanup
misc: remove AVR32 dependencies
virt: vbox: Add error mapping for VERR_INVALID_NAME and VERR_NO_MORE_FILES
soundwire: Fix a signedness bug
uio_hv_generic: fix new type mismatch warnings
uio_hv_generic: fix type mismatch warnings
auxdisplay: img-ascii-lcd: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
uio_hv_generic: add rescind support
uio_hv_generic: check that host supports monitor page
uio_hv_generic: create send and receive buffers
uio: document uio_hv_generic regions
doc: fix documentation about uio_hv_generic
vmbus: add monitor_id and subchannel_id to sysfs per channel
vmbus: fix ABI documentation
uio_hv_generic: use ISR callback method
...
SoundWire bus provides sdw_read() and sdw_write() APIs for Slave
devices to program the registers. Provide support in regmap for
SoundWire bus.
Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com>
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds support to read/write SLIMbus value elements.
Currently it only supports byte read/write. Adding this support in
regmap would give codec drivers more flexibility when there are more
than 2 control interfaces like SLIMbus, i2c.
Without this patch each codec driver has to directly call SLIMbus value
element apis, and this could would get messy once we want to add i2c
interface to it.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The hwspinlock was changed to a bool by commit d048236dfd
("hwspinlock: Change hwspinlock to a bool"), so we do not need
the REGMAP_HWSPINLOCK config to select hwspinlock or not.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
After several quiet kernel releases we've got a couple of new features
in regmap, support for using hwspinlocks as the lock for the internal
data structures and a helper for polling on regmap_fields. The Kconfig
dependencies on hwspinlocks were annoyingly difficult to squash between
things behaving surprisingly and randconfig, I could've squashed those
commits down but might've have caused hassle with other trees trying to
use the new support.
- Support for using a hwspinlock to protect the regmap.
- An iopoll style helper for regmap_field.
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Merge tag 'regmap-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap
Pull regmap updates from Mark Brown:
"After several quiet kernel releases we've got a couple of new features
in regmap, support for using hwspinlocks as the lock for the internal
data structures and a helper for polling on regmap_fields. The Kconfig
dependencies on hwspinlocks were annoyingly difficult to squash
between things behaving surprisingly and randconfig, I could've
squashed those commits down but might've have caused hassle with other
trees trying to use the new support.
- support for using a hwspinlock to protect the regmap
- an iopoll style helper for regmap_field"
* tag 'regmap-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: Fix unused warning
regmap: Try to work around Kconfig exploding on HWSPINLOCK
regmap: Clean up hwspinlock on regmap exit
regmap: Also protect hwspinlock in error handling path
regmap: Add a config option for hwspinlock
regmap: Add hardware spinlock support
regmap: avoid -Wint-in-bool-context warning
regmap: add iopoll-like polling macro for regmap_field
regmap: constify regmap_bus structures
regmap: Avoid namespace collision within macro & tidy up
Trying to work with hwspinlock from built in code is painful as it can
be built modular. Invert the test for REGMAP_HWSPINLOCK for now so we
end up requiring users to depend on HWSPINLOCK=y in order to turn on the
hwspinlock code.
Signed-off-by: Mark Brown <broonie@kernel.org>
Unlike other lock types hwspinlocks are optional and can be built
modular so we can't use them unconditionally in regmap so add a config
option that drivers that want to use hwspinlocks with regmap can select
which will ensure that hwspinlock is built in.
Signed-off-by: Mark Brown <broonie@kernel.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 2cbbb579bc ("regmap: Add the LZO cache support") added support
for LZO compression in regcache, but there were never any users added
afterwards. Since LZO support itself has its own size, it currently is
rather a deoptimization.
So make it optional by introducing a symbol that can be selected by
drivers wanting to make use of it.
Saves e.g. ~46 kB on MIPS (size of LZO support + regcache LZO code).
Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use the recently added support for bus operations to provide a standard
mapping for AC'97 register I/O.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Add explicit dependencies for the various regmap modules, so Kconfig
will print a warning message when another module selects a regmap module
without fulfilling its dependencies.
Without this, it's much more difficult to find out which module did the
offending select.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Add basic support for the System Power Management Interface (SPMI) bus.
This is a simple implementation which only implements register accesses
via the Extended Register Read/Write Long commands.
Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
The regmap_mmio and regmap_irq depend on regmap core, if not select,
we may not compile regmap core and meet compiling errors as follows
if REGMAP_MMIO is selected by client drivers:
drivers/mfd/syscon.c:94:15: error: variable 'syscon_regmap_config' has initializer but incomplete type
drivers/mfd/syscon.c:95:2: error: unknown field 'reg_bits' specified in initializer
drivers/mfd/syscon.c:95:2: warning: excess elements in struct initializer [enabled by default]
drivers/mfd/syscon.c:95:2: warning: (near initialization for 'syscon_regmap_config') [enabled by default]
drivers/mfd/syscon.c:96:2: error: unknown field 'val_bits' specified in initializer
drivers/mfd/syscon.c:96:2: warning: excess elements in struct initializer [enabled by default]
drivers/mfd/syscon.c:96:2: warning: (near initialization for 'syscon_regmap_config') [enabled by default]
drivers/mfd/syscon.c:97:2: error: unknown field 'reg_stride' specified in initializer
drivers/mfd/syscon.c:97:2: warning: excess elements in struct initializer [enabled by default]
drivers/mfd/syscon.c:97:2: warning: (near initialization for 'syscon_regmap_config') [enabled by default]
drivers/mfd/syscon.c: In function 'syscon_probe':
drivers/mfd/syscon.c:124:2: error: invalid use of undefined type 'struct regmap_config'
drivers/mfd/syscon.c:125:2: error: implicit declaration of function 'devm_regmap_init_mmio' [-Werror=implicit-function-declaration]
drivers/mfd/syscon.c:125:17: warning: assignment makes pointer from integer without a cast [enabled by default]
cc1: some warnings being treated as errors
drivers/mfd/Kconfig:
config MFD_SYSCON
bool "System Controller Register R/W Based on Regmap"
depends on OF
select REGMAP_MMIO
help
Select this option to enable accessing system control registers
via regmap.
Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Ensure that we can't get randconfig breakage by doing the IRQ_DOMAIN
select automatically. Don't just do the select from REGMAP_IRQ to ensure
that the select actually gets noticed.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Mark 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: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark 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: Mark 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: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
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>
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>
There are many places in the tree where we implement register access for
devices on non-memory mapped buses, especially I2C and SPI. Since hardware
designers seem to have settled on a relatively consistent set of register
interfaces this can be effectively factored out into shared code. There
are a standard set of formats for marshalling data for exchange with the
device, with the actual I/O mechanisms generally being simple byte
streams.
We create an abstraction for marshaling data into formats which can be
sent on the control interfaces, and create a standard method for
plugging in actual transport underneath that.
This is mostly a refactoring and renaming of the bottom level of the
existing code for sharing register I/O which we have in ASoC. A
subsequent patch in this series converts ASoC to use this. The main
difference in interface is that reads return values by writing to a
location provided by a pointer rather than in the return value, ensuring
we can use the full range of the type for register data. We also use
unsigned types rather than ints for the same reason.
As some of the devices can have very large register maps the existing
ASoC code also contains infrastructure for managing register caches.
This cache work will be moved over in a future stage to allow for
separate review, the current patch only deals with the physical I/O.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
