Commit Graph

126 Commits

Author SHA1 Message Date
Nariman Poushin 8019ff6cfc regmap: Use reg_sequence for multi_reg_write / register_patch
Separate the functionality using sequences of register writes from the
functions that take register defaults. This change renames the arguments
in order to support the extension of reg_sequence to take an optional
delay to be applied after any given register in a sequence is written.
This avoids adding an int to all register defaults, which could
substantially increase memory usage for regmaps with large default tables.

This also updates all the clients of multi_reg_write/register_patch.

Signed-off-by: Nariman Poushin <nariman@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-16 22:02:55 +01:00
Srinivas Kandagatla a2f776cbb8 regmap: Introduce regmap_get_reg_stride
This patch introduces regmap_get_reg_stride() function which would
be used by the infrastructures like nvmem framework built on top of
regmap. Mostly this function would be used for sanity checks on inputs
within such infrastructure.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-05-22 12:19:21 +01:00
Srinivas Kandagatla 668abc729f regmap: Introduce regmap_get_max_register
This patch introduces regmap_get_max_register() function which would be
used by the infrastructures like nvmem framework built on top of
regmap.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-05-22 12:19:18 +01:00
Bintian Wang f27b37f599 regmap: correct the description of structure element in reg_field
Fix incorrect description of structure element "msb", which is
described as "reg".

Signed-off-by: Bintian Wang <bintian.wang@huawei.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2015-01-27 13:13:04 +00:00
Mark Brown 22853223d1 regmap: ac97: Add generic AC'97 callbacks
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>
2014-11-19 10:28:14 +00:00
Mark Brown 1d33dc6b0f regmap: Fix return code for stub regmap_get_device()
We return a pointer, not an int.

Signed-off-by: Mark Brown <broonie@linaro.org>
2014-07-25 19:01:53 +01:00
Tuomas Tynkkynen 8d7d3972a9 regmap: Add regmap_get_device
Add a new function regmap_get_device to obtain the underlying struct
device from a regmap.

Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-07-25 18:29:28 +01:00
Boris BREZILLON 3ac170376f regmap: add reg_read/reg_write callbacks to regmap_bus struct
Some busses do not support sending/receiving multiple registers in one go.
Such kind of busses just unpack the registers that have been previously
packed by the regmap core or pack registers that will be later unpacked by
the core code.

Add reg_write and reg_read callbacks in order to optimize access through
this kind of busses.

Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-18 16:07:22 +01:00
Linus Torvalds 675c354a95 Char/Misc driver patches for 3.15-rc1
Here's the big char/misc driver updates for 3.15-rc1.
 
 Lots of various things here, including the new mcb driver subsystem.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver patches from Greg KH:
 "Here's the big char/misc driver updates for 3.15-rc1.

  Lots of various things here, including the new mcb driver subsystem.

  All of these have been in linux-next for a while"

* tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (118 commits)
  extcon: Move OF helper function to extcon core and change function name
  extcon: of: Remove unnecessary function call by using the name of device_node
  extcon: gpio: Use SIMPLE_DEV_PM_OPS macro
  extcon: palmas: Use SIMPLE_DEV_PM_OPS macro
  mei: don't use deprecated DEFINE_PCI_DEVICE_TABLE macro
  mei: amthif: fix checkpatch error
  mei: client.h fix checkpatch errors
  mei: use cl_dbg where appropriate
  mei: fix Unnecessary space after function pointer name
  mei: report consistently copy_from/to_user failures
  mei: drop pr_fmt macros
  mei: make me hw headers private to me hw.
  mei: fix memory leak of pending write cb objects
  mei: me: do not reset when less than expected data is received
  drivers: mcb: Fix build error discovered by 0-day bot
  cs5535-mfgpt: Simplify dependencies
  spmi: pm: drop bus-level PM suspend/resume routines
  spmi: pmic_arb: make selectable on ARCH_QCOM
  Drivers: hv: vmbus: Increase the limit on the number of pfns we can handle
  pch_phub: Report error writing MAC back to user
  ...
2014-04-01 16:13:21 -07:00
Mark Brown 6012b1f342 Merge remote-tracking branches 'regmap/topic/cache', 'regmap/topic/irq', 'regmap/topic/lock', 'regmap/topic/mmio', 'regmap/topic/nodev', 'regmap/topic/parse-val' and 'regmap/topic/patch' into regmap-next 2014-03-28 11:50:43 +00:00
Opensource [Anthony Olech] e894c3f46c regmap: Implementation for regmap_multi_reg_write
This is the implementation of regmap_multi_reg_write()

There is a new capability 'can_multi_write' that device drivers
must set in order to use this multi reg write mode.

This replaces the first definition, which just defined the API.

Signed-off-by: Anthony Olech <anthony.olech.opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-03-10 17:09:32 +00:00
Nenghua Cao 13ff50c858 regmap: add regmap_parse_val api
In some cases, we need regmap's format parse_val function
to do be/le translation according to the bus configuration.
For example, snd_soc_bytes_put() uses regmap to write/read values,
and use cpu_to_be() directly to covert MASK into big endian. This
is a defect, and should use regmap's format function to do it according
to bus configuration.

Signed-off-by: Nenghua Cao <nhcao@marvell.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-03-06 17:40:54 +08:00
Charles Keepax 1d5b40bccf regmap: Add bypassed version of regmap_multi_reg_write
Devices with more complex boot proceedures may occasionally apply the
register patch manual. regmap_multi_reg_write is a logical way to do so,
however the patch must be applied with cache bypass on, such that it
doesn't override any user settings. This patch adds a
regmap_multi_reg_write_bypassed function that applies a set of writes
with the bypass enabled.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-02-26 08:58:40 +09:00
Charles Keepax f7e2cec02b regmap: Mark reg_defaults in regmap_multi_reg_write as const
There should be no need for the writes supplied to this function to be
edited by it so mark them as const.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-02-26 08:58:40 +09:00
Michal Simek 6cfec04bcc regmap: Separate regmap dev initialization
Create special function regmap_attach_dev
which can be called separately out of regmap_init.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-02-16 09:53:02 +08:00
Josh Cartwright c9afbb05a9 regmap: spmi: support base and extended register spaces
SPMI states that a slave may contain two register spaces, the Base
register space is a 5-bit byte-addressable space accessed via the
Register Read/Write and Register Zero Write command sequences, and the
Extended register space: a 16-bit byte-addressable space accessed via
the Extended Read/Write and Extended Read/Write Long command sequences.

Provide support for accessing both of these spaces, taking advantage of
the more bandwidth-efficient commands ('Register 0 Write' vs 'Register
Write', and 'Extended Register Read/Write' vs 'Extended Register
Read/Write Long') when possible.

Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Acked-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-15 11:55:28 -08:00
Mark Brown 86776fc174 Merge remote-tracking branch 'regmap/topic/ack' into regmap-next 2014-01-09 14:34:13 +00:00
Laszlo Papp bdc39644b5 regmap: fix a couple of typos
These sentences are not proper English due to the typos. I had initially caught
one of them while trying to understand the regmap feature, and then I just ran
the vim spell checker, and went through all the items that would need to be
fixed for this header file.

Signed-off-by: Laszlo Papp <lpapp@kde.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-01-09 14:20:54 +00:00
Alexander Shiyan d323343335 regmap: irq: Allow using zero value for ack_base
In some cases, clear interrupt register may be at address 0.
This patch allows to use such configurations by adding additional
configuration bit to indicate this.

[With doc fix from Levente Kurusa <levex@linux.com> -- broonie]

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-16 20:50:13 +00:00
Mark Brown 04bc9ac163 Merge remote-tracking branch 'regmap/topic/spmi' into regmap-next 2013-10-28 13:01:35 -07:00
Mark Brown c435d5b9b8 Merge remote-tracking branch 'regmap/topic/range' into regmap-next 2013-10-28 13:01:35 -07:00
Mark Brown 18f513db93 Merge remote-tracking branch 'regmap/topic/multi' into regmap-next 2013-10-28 13:01:34 -07:00
Mark Brown f2783f0e9c Merge remote-tracking branch 'regmap/topic/field' into regmap-next 2013-10-28 13:01:33 -07:00
Josh Cartwright a01779f89f regmap: add SPMI support
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>
2013-10-28 12:51:43 -07:00
Anthony Olech e33fabd365 regmap: new API regmap_multi_reg_write() definition
New API regmap_multi_reg_write() is defined that allows a set of reg,val
pairs to be written to a I2C client device as one block transfer from the
point of view of a single I2C master system.

A simple demonstration implementation is included that just splits the
block write request into a sequence of single register writes.

The implementation will be modified later to support those I2C clients
that implement the alternative non-standard MULTIWRITE block write mode
so to achieve a single I2C transfer that will be atomic even in multiple
I2C master systems.

Signed-off-by: Anthony Olech <anthony.olech.opensource@diasemi.com>
Signed-off-by: David Dajun Chen <david.chen@diasemi.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-10-14 15:09:16 +01:00
Mark Brown 915f441b6f regmap: Provide asynchronous write and update bits operations
Make it easier for drivers to include single register writes in
asynchronous sequences by providing async versions of the write
and update bits operations. The update bits operations are only
likely to be effective when used with devices that have caches
but this is common enough to be useful.

Signed-off-by: Mark Brown <broonie@linaro.org>
2013-10-09 14:05:26 +01:00
Laxman Dewangan 6112fe60ac regmap: add helper macro to set min/max range of register
Add helper macro to set the min and max value of the register range.

This is useful when initialising the register ranges of the device like

static const struct regmap_range readable_ranges[] = {
	regmap_reg_range(DEVICE_REG0, DEVICE_REG10),
};

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-09-20 17:50:46 +01:00
Kuninori Morimoto a0102375ee regmap: Add regmap_fields APIs
Current Linux kernel is supporting regmap_field method
and it is very useful feature.
It needs one regmap_filed for one register access.

OTOH, there is multi port device which
has many same registers in the market.
The difference for each register access is
only its address offset.

Current API needs many regmap_field for such device,
but it is not good.
This patch adds new regmap_fileds API which can care
about multi port/offset access via regmap.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-09-17 13:46:57 +01:00
Kuninori Morimoto fdf2002905 regmap: add regmap_field_update_bits()
Current regmap_field is supporting read/write functions.
This patch adds new update_bits function for it.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-09-17 00:12:23 +01:00
Linus Torvalds 8243b7f5dc regmap: Updates for v3.12
A quiet release for regmap, some cleanups, fixes and:
 
  - Improved node coalescing for rbtree, reducing memory usage and
    improving performance during syncs.
  - Support for registering multiple register patches.
  - A quirk for handling interrupts that need to be clear when masked
    in regmap-irq.
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Merge tag 'regmap-v3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap

Pull regmap updates from Mark Brown:
 "A quiet release for regmap, some cleanups, fixes and:

   - Improved node coalescing for rbtree, reducing memory usage and
     improving performance during syncs.
   - Support for registering multiple register patches.
   - A quirk for handling interrupts that need to be clear when masked
     in regmap-irq"

* tag 'regmap-v3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: rbtree: Make cache_present bitmap per node
  regmap: rbtree: Reduce number of nodes, take 2
  regmap: rbtree: Simplify adjacent node look-up
  regmap: debugfs: Fix continued read from registers file
  regcache-rbtree: Fix reg_stride != 1
  regmap: Allow multiple patches to be registered
  regmap: regcache: allow read-only regs to be cached
  regmap: fix regcache_reg_present() for empty cache
  regmap: core: allow a virtual range to cover its own data window
  regmap: irq: document mask/wake_invert flags
  regmap: irq: make flags bool and put them in a bitfield
  regmap: irq: Allow to acknowledge masked interrupts during initialization
  regmap: Provide __acquires/__releases annotations
2013-09-03 10:07:40 -07:00
Mark Brown 1801ceaf07 Merge remote-tracking branch 'regmap/topic/irq' into regmap-next 2013-08-31 19:25:12 +01:00
Kevin Hilman 3f0fa9a808 regmap: Add another missing header for !CONFIG_REGMAP stubs
The use of WARN_ON() needs the definitions from bug.h, without it
you can get:

include/linux/regmap.h: In function 'regmap_write':
include/linux/regmap.h:525:2: error: implicit declaration of function 'WARN_ONCE' [-Werror=implicit-function-declaration]

Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org
2013-08-15 12:08:55 +01:00
Mateusz Krawczuk 49ccc142f9 regmap: Add missing header for !CONFIG_REGMAP stubs
regmap.h requires linux/err.h if CONFIG_REGMAP is not defined. Without it I get
error.
CC      drivers/media/platform/exynos4-is/fimc-reg.o
In file included from drivers/media/platform/exynos4-is/fimc-reg.c:14:0:
include/linux/regmap.h: In function ‘regmap_write’:
include/linux/regmap.h:525:10: error: ‘EINVAL’ undeclared (first use in this function)
include/linux/regmap.h:525:10: note: each undeclared identifier is reported only once for each function it appears in

Signed-off-by: Mateusz Krawczuk <m.krawczuk@partner.samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@kernel.org
2013-08-06 19:49:46 +01:00
Philipp Zabel 68622bdfef regmap: irq: document mask/wake_invert flags
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-07-24 16:55:30 +01:00
Philipp Zabel f484f7a6bc regmap: irq: make flags bool and put them in a bitfield
This patch makes mask/wake_invert bool and puts all flags into a bitfield
for consistency and to save some space.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-07-24 16:55:30 +01:00
Philipp Zabel 2753e6f820 regmap: irq: Allow to acknowledge masked interrupts during initialization
In case the hardware interrupt mask register does not prevent the chip level
irq from being asserted by the corresponding interrupt status bit, already
set interrupt bits should to be cleared once after masking them during
initialization. Add a flag to let drivers enable this behavior.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-07-23 20:39:12 +01:00
Mark Brown 7bc8c4c37a Merge remote-tracking branch 'regmap/topic/field' into regmap-next 2013-06-30 12:40:03 +01:00
Srinivas Kandagatla 6725228787 regmap: Add regmap_field APIs
It is common to access regmap registers at bit level, using
regmap_update_bits or regmap_read functions, however the end user has to
take care of a mask or shifting. This becomes overhead when such use
cases are high. Having a common function to do this is much convenient
and less error prone.

The idea of regmap_field is simple, regmap_field gives a logical
structure to bits of the regmap register, and the driver can use this
logical entity without the knowledge of the bit positions and masks all
over the code. This way code looks much neat and it need not handle the
masks, shifts every time it access the those entities.

With this new regmap_field_read/write apis the end user can setup a
regmap field using regmap_field_init and use the return regmap_field to
read write the register field without worrying about the masks or
shifts.

Also this apis will be useful for drivers which are based on regmaps,
like some clocks or pinctrls which can work on the regmap_fields
directly without having to worry about bit positions.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-06-12 16:27:44 +01:00
Mark Brown 154881e59b regmap: Make regmap_check_range_table() a public API
Allow drivers to use an access table as part of their implementation.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-12 18:46:47 +04:00
Mark Brown 697e85bc6a regmap: Add support for discarding parts of the register cache
Allow drivers to discard parts of the register cache, for example if part
of the hardware has been reset.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-12 18:46:47 +04:00
Mark Brown 221ad7f2df regmap: core: Provide regmap_can_raw_write() operation
Mainly useful internally but exported since this is a public API that's
being checked for.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-27 13:03:39 +00:00
Mark Brown a2b37efc4e Merge remote-tracking branch 'regmap/topic/no-bus' into regmap-next 2013-02-14 17:11:09 +00:00
Mark Brown a31f68497e Merge remote-tracking branch 'regmap/topic/mmio' into regmap-next 2013-02-14 17:11:08 +00:00
Mark Brown 5dea215028 Merge remote-tracking branch 'regmap/topic/irq' into regmap-next 2013-02-14 17:11:08 +00:00
Mark Brown 7798b582d3 Merge remote-tracking branch 'regmap/topic/flat' into regmap-next 2013-02-14 17:11:07 +00:00
Philipp Zabel 878ec67b3a regmap: mmio: add register clock support
Some mmio devices have a dedicated interface clock that needs
to be enabled to access their registers. This patch optionally
enables a clock before accessing registers in the regmap_bus
callbacks.

I added (devm_)regmap_init_mmio_clk variants of the init
functions that have an added clk_id string parameter. This
is passed to clk_get to request the clock from the clk
framework.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-14 16:40:28 +00:00
Mark Brown 0d509f2b11 regmap: Add asynchronous I/O support
Some use cases like firmware download can transfer a lot of data in quick
succession. With high speed buses these use cases can benefit from having
multiple transfers scheduled at once since this allows the bus to minimise
the delay between transfers.

Support this by adding regmap_raw_write_async(), allowing raw transfers to
be scheduled, and regmap_async_complete() to wait for them to finish.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-01-29 12:14:52 +08:00
Andrey Smirnov d2a5884a64 regmap: Add "no-bus" option for regmap API
This commit adds provision for "no-bus" usage of the regmap API. In
this configuration user can provide API with two callbacks 'reg_read'
and 'reg_write' which are to be called when reads and writes to one of
device's registers is performed. This is useful for devices that
expose registers but whose register access sequence does not fit the 'bus'
abstraction.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-01-29 11:42:49 +08:00
Mark Brown 9442490a02 regmap: irq: Support wake IRQ mask inversion
Support devices which have an enable rather than mask register for wake
sources.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-01-04 20:53:44 +00:00
Mark Brown 2ac902ce17 regmap: flat: Add flat cache type
While for I2C and SPI devices the overhead of using rbtree for devices with
only one block of registers is negligible the same isn't always going to
be true for MMIO devices where the I/O costs are very much lower. Cater
for these devices by adding a simple flat array type for them where the
lookups are simple array accesses, taking us right back to the original
ASoC cache implementation.

Thanks to Magnus Damm for the discussion which prompted this.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-01-02 10:58:53 +00:00