Commit Graph

2524 Commits

Author SHA1 Message Date
Andy Shevchenko
c99d49a964 i2c: designware-pci: no need to provide clk_khz
The clk_khz field makes sense only if SS counters are not provided. Since we
provide them for Haswell and Baytrail explicitly we may omit the clk_khz
parameter.

Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-23 15:38:13 +01:00
Andy Shevchenko
bd1179fd56 i2c: designware-pci: remove Moorestown support
The Moorestown support bits were removed few years ago. This is a follow up to
that changes.

Suggested-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-23 15:38:12 +01:00
Philipp Zabel
4e355f5128 i2c: imx: whitespace and checkpatch cleanup
This patch fixes up some whitespace issues and addresses a few
checkpatch warnings.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-22 16:34:39 +01:00
Wolfram Sang
a5eb71b207 i2c: simplify boilerplate code for attribute groups
Declaring attribute groups can be done with macros these days, let's use
them for consistency and readability reasons. Also, put the ATTR macros
directly below the referenced functions while we are here.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-22 15:26:50 +01:00
Philipp Zabel
90ebd0eb06 i2c: imx: remove unused return value assignments
The ret variable is set and never used in the error path of i2c_imx_dma_request.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-14 15:18:51 +01:00
Mika Westerberg
393cc1ceb9 i2c: ACPI: Pick the first address if device has multiple
ACPI specification allows I2C devices with multiple addresses. The current
implementation goes over all addresses and assigns the last one to the
device. This is typically not the primary address of the device.

Instead of doing that we assign the first address to the device and then
let the driver handle rest of the addresses as it wishes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-14 11:56:06 +01:00
Harini Katakam
8a86c3aee0 i2c: cadence: Check for errata condition involving master receive
Cadence I2C controller has the following bugs:
- completion indication is not given to the driver at the end of
a read/receive transfer with HOLD bit set.
- Invalid read transaction are generated on the bus when HW timeout
condition occurs with HOLD bit set.

As a result of the above, if a set of messages to be transferred with
repeated start includes any message following a read message,
completion is never indicated and timeout occurs.
Hence a check is implemented to return -EOPNOTSUPP for such sequences.

Signed-off-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Vishnu Motghare <vishnum@xilinx.com>
[wsa: fixed some whitespaces]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-14 11:36:58 +01:00
Nicholas Mc Guire
cb9eaba4c5 i2c: imx: fix handling of wait_for_completion_timeout result
wait_for_completion_timeout does not return negative values so
"result" handling here should be simplified to cover the actually
possible cases only.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 16:21:07 +01:00
Doug Anderson
387f0de6c3 i2c: rk3x: Account for repeated start time requirement
On Rockchip I2C the controller drops SDA low slightly too soon to meet
the "repeated start" requirements.

>From my own experimentation over a number of rates:
 - controller appears to drop SDA at .875x (7/8) programmed clk high.
 - controller appears to keep SCL high for 2x programmed clk high.

The first rule isn't enough to meet tSU;STA requirements in
Standard-mode on the system I tested on.  The second rule is probably
enough to meet tHD;STA requirements in nearly all cases (especially
after accounting for the first), but it doesn't hurt to account for it
anyway just in case.

Even though the repeated start requirement only need to be accounted
for during a small part of the transfer, we'll adjust the timings for
the whole transfer to meet it.  I believe that adjusting the timings
in just the right place to switch things up for repeated start would
require several extra interrupts and that doesn't seem terribly worth
it.

With this change and worst case rise/fall times, I see 100kHz i2c
going to ~85kHz.  With slightly optimized rise/fall (800ns / 50ns) I
see i2c going to ~89kHz.  Fast-mode isn't affected much because
tSU;STA is shorter relative to tHD;STA there.

As part of this change we needed to account for the SDA falling time.
The specification indicates that this should be the same, but we'll
follow Designware's lead and add a binding.  Note that we deviate from
Designware and assign the default SDA falling time to be the same as
the SCL falling time, which is incredibly likely.

Signed-off-by: Doug Anderson <dianders@chromium.org>
[wsa: rebased to i2c/for-next]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 16:21:05 +01:00
addy ke
1330e29105 i2c: rk3x: fix bug that cause measured high_ns doesn't meet I2C specification
The number of clock cycles to be written into the CLKDIV register
that determines the I2C clk high phase includes the rise time.
So to meet the timing requirements defined in the I2C specification
which defines the minimal time SCL has to be high, the rise time
has to taken into account. The same applies to the low phase with
falling time.

In my test on RK3288-Pink2 board, which is not an upstream board yet,
if external pull-up resistor is 4.7K, rise_ns is about 700ns.
So the measured high_ns is about 3900ns, which is less than 4000ns
(the minimum high_ns in I2C specification for Standard-mode).

To fix this bug min_low_ns should include fall time and min_high_ns
should include rise time.

This patch merged the patch from chromium project which can get the
rise and fall times for signals from the device tree. This allows us
to more accurately calculate timings. see:
https://chromium-review.googlesource.com/#/c/232774/

Signed-off-by: Addy Ke <addy.ke@rock-chips.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
[wsa: fixed a typo in the docs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 16:21:04 +01:00
Harini Katakam
9fae82e1ac i2c: cadence: Handle > 252 byte transfers
The I2C controller sends a NACK to the slave when transfer size register
reaches zero, irrespective of the hold bit. So, in order to handle transfers
greater than 252 bytes, the transfer size register has to be maintained at a
value >= 1. This patch implements the same.
The interrupt status is cleared at the beginning of the isr instead of
the end, to avoid missing any interrupts.

Signed-off-by: Harini Katakam <harinik@xilinx.com>
[wsa: added braces around else branch]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 16:21:03 +01:00
Wolfram Sang
1c57499361 i2c: pmcmsp: remove dead code
CPPCHECK rightfully says:

drivers/i2c/busses/i2c-pmcmsp.c:151: style: The function 'pmcmsptwi_reg_to_clock' is never used.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 10:37:43 +01:00
Lars-Peter Clausen
523c5b8964 i2c: Remove support for legacy PM
There haven't been any I2C driver that use the legacy suspend/resume
callbacks for a while now and new drivers are supposed to use PM ops. So
remove support for legacy suspend/resume for I2C drivers.

Since there aren't any special bus specific things to do during
suspend/resume and since the PM core will automatically fallback directly to
using the device's PM ops if no bus PM ops are specified there is no need to
have any I2C bus PM ops.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-22 20:09:08 +01:00
Linus Torvalds
a4e1328a9d Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull more i2c updates from Wolfram Sang:
 "Included are two bugfixes needing some bigger refactoring (sh_mobile:
  deferred probe with DMA, mv64xxx: fix offload support) and one
  deprecated driver removal I thought would go in via ppc but I
  misunderstood.  It has a proper ack from BenH"

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: sh_mobile: fix uninitialized var when debug is enabled
  macintosh: therm_pm72: delete deprecated driver
  i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMA
  i2c: sh_mobile: rework deferred probing
  i2c: sh_mobile: refactor DMA setup
  i2c: mv64xxx: rework offload support to fix several problems
  i2c: mv64xxx: use BIT() macro for register value definitions
2014-12-20 13:52:52 -08:00
Wolfram Sang
fe07adec73 i2c: sh_mobile: fix uninitialized var when debug is enabled
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-20 09:28:09 +01:00
Linus Torvalds
34b85e3574 powerpc updates for 3.19 batch 2
The highlight is the series that reworks the idle management on powernv, which
 allows us to use deeper idle states on those machines.
 
 There's the fix from Anton for the "BUG at kernel/smpboot.c:134!" problem.
 
 An i2c driver for powernv. This is acked by Wolfram Sang, and he asked that we
 take it through the powerpc tree.
 
 A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of the audit
 maintainers.
 
 A patch from Ben to export the symbol map of our OPAL firmware as a sysfs file,
 so that tools can use it.
 
 Also some CXL fixes, a couple of powerpc perf fixes, a fix for smt-enabled, and
 the patch to add __force to get_user() so we can use bitwise types.
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Merge tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull second batch of powerpc updates from Michael Ellerman:
 "The highlight is the series that reworks the idle management on
  powernv, which allows us to use deeper idle states on those machines.

  There's the fix from Anton for the "BUG at kernel/smpboot.c:134!"
  problem.

  An i2c driver for powernv.  This is acked by Wolfram Sang, and he
  asked that we take it through the powerpc tree.

  A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of
  the audit maintainers.

  A patch from Ben to export the symbol map of our OPAL firmware as a
  sysfs file, so that tools can use it.

  Also some CXL fixes, a couple of powerpc perf fixes, a fix for
  smt-enabled, and the patch to add __force to get_user() so we can use
  bitwise types"

* tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux:
  powerpc/powernv: Ignore smt-enabled on Power8 and later
  powerpc/uaccess: Allow get_user() with bitwise types
  powerpc/powernv: Expose OPAL firmware symbol map
  powernv/powerpc: Add winkle support for offline cpus
  powernv/cpuidle: Redesign idle states management
  powerpc/powernv: Enable Offline CPUs to enter deep idle states
  powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode
  i2c: Driver to expose PowerNV platform i2c busses
  powerpc: add little endian flag to syscall_get_arch()
  power/perf/hv-24x7: Use kmem_cache_free() instead of kfree
  powerpc/perf/hv-24x7: Use per-cpu page buffer
  cxl: Unmap MMIO regions when detaching a context
  cxl: Add timeout to process element commands
  cxl: Change contexts_lock to a mutex to fix sleep while atomic bug
  powerpc: Secondary CPUs must set cpu_callin_map after setting active and online
2014-12-19 12:57:45 -08:00
Geert Uytterhoeven
f16ea4f0e1 i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMA
If NO_DMA=y:

drivers/built-in.o: In function `sh_mobile_i2c_dma_unmap':
i2c-sh_mobile.c:(.text+0x60de42): undefined reference to `dma_unmap_single'
drivers/built-in.o: In function `sh_mobile_i2c_xfer_dma':
i2c-sh_mobile.c:(.text+0x60df22): undefined reference to `dma_map_single'
i2c-sh_mobile.c:(.text+0x60df2e): undefined reference to `dma_mapping_error'

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17 19:26:09 +01:00
Wolfram Sang
55f5f9862a i2c: sh_mobile: rework deferred probing
DMA is opt-in for this driver. So, we can't use deferred probing for
requesting DMA channels in probe, because our driver would get endlessly
deferred if DMA support is compiled in AND the DMA driver is missing.
Because we can't know when the DMA driver might show up, we always try
again when a DMA transfer would be possible. The downside is that there
is more overhead for setting up PIO transfers under the above scenario.
But well, having DMA enabled and the proper DMA driver missing looks
like a broken or test config anyhow.

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17 19:26:08 +01:00
Wolfram Sang
e844a7997d i2c: sh_mobile: refactor DMA setup
Refactor DMA setup to keep the errno so we can implement better
deferred probe support in the next step.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17 19:26:07 +01:00
Thomas Petazzoni
00d8689b85 i2c: mv64xxx: rework offload support to fix several problems
Originally, the I2C controller supported by the i2c-mv64xxx driver
requires a lot of software support: an interrupt is generated at each
step of an I2C transaction (after the start bit, after sending the
address, etc.) and the driver is in charge of re-programming the I2C
controller to do the next step of the I2C transaction. This explains
the fairly complex state machine that the driver has.

On Marvell Armada XP and later processors (Armada 375, 38x, etc.), the
I2C controller was extended with a part called the "I2C Bridge", which
allows to offload the I2C transaction completely to the
hardware. Initial support for this mechanism was added in commit
930ab3d403 ("i2c: mv64xxx: Add I2C Transaction Generator support").

However, the implementation done in this commit has two related
issues, which this commit fixes by completely changing how the offload
implementation is done:

 * SMBus read transfers, where there is one write to select the
   register immediately followed in the same transaction by one read,
   were making the processor hang. This was easier visible on the
   Marvell Armada XP WRT1900AC platform using a driver for an I2C LED
   controller, or on other Armada XP platforms by using a simple
   'i2cget' command to read an I2C EEPROM.

 * The implementation was based on the fact that the offload engine
   was re-programmed to transfer each message of an I2C xfer: this
   meant that each message sent with the offload engine was starting
   with a normal I2C start sequence. However, the I2C subsystem
   assumes that all messages belonging to the same xfer will use the
   so-called "repeated start" so that the entire I2C xfer is seen as
   one transfer by the I2C devices and cannot be interrupt by other
   I2C masters on the same bus.

In fact, the "I2C Bridge" allows to offload three types of xfer:

 - xfer of one write message
 - xfer of one read message
 - xfer of one write message followed by one read message

For all other situations, we have to fallback to not using the "I2C
Bridge" in order to get proper I2C semantics.

Therefore, this commit reworks the offload implementation to put it
not at the message level, but at the xfer level: in the
mv64xxx_i2c_xfer() function, we decide if the transaction can be
offloaded (in which case it is handled by the
mv64xxx_i2c_offload_xfer() function), or otherwise it is handled by
the slow path (implemented in the existing mv64xxx_i2c_execute_msg()).

This allows to simplify the state machine, which no longer needs to
have any state related to the offload implementation: the offload
implementation is now completely separated from the slow path (with
the exception of the interrupt handler, of course).

In summary:

 - mv64xxx_i2c_can_offload() will analyze an I2C xfer and decided of
   the "I2C Bridge" can be used to offload it or not.

 - mv64xxx_i2c_offload_xfer() will actually program the "I2C Bridge"
   to offload one xfer (of either one or two messages), and block
   using mv64xxx_i2c_wait_for_completion() until the xfer completes.

 - The interrupt handler mv64xxx_i2c_intr() is modified to push the
   offload related code to a separate function,
   mv64xxx_i2c_intr_offload(). It will take care of reading the
   received data if needed.

This commit was tested on:

 - Armada XP OpenBlocks AX3-4 (EEPROM on I2C and RTC on I2C)
 - Armada XP WRT1900AC (LED controller on I2C)
 - Armada XP GP (EEPROM on I2C)

Fixes: 930ab3d403 ("i2c: mv64xxx: Add I2C Transaction Generator support")
Cc: <stable@vger.kernel.org> # v3.12+
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
[wsa: fixed checkpatch warnings]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17 19:26:03 +01:00
Thomas Petazzoni
12598695c2 i2c: mv64xxx: use BIT() macro for register value definitions
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17 19:25:55 +01:00
Linus Torvalds
e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Linus Torvalds
96895199c8 Merge branch 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "For 3.19, the I2C subsystem has to offer special candy this time.
  Right in time for Christmas :)

   - I2C slave framework: finally, a generic mechanism for Linux being
     an I2C slave (if the bus driver supports that).  Docs are still
     missing but will come later this cycle, the code is good enough to
     go.
   - I2C muxes represent their topology in sysfs much more detailed.
     This will help users to navigate around much easier.
   - irq population of i2c clients is now done at probe time, not device
     creation time, to have better support for deferred probing.
   - new drivers for Imagination SCB, Amlogic Meson
   - DMA support added for Freescale IMX, Renesas SHMobile
   - slightly bigger driver updates to OMAP, i801, AT91, and rk3x
     (mostly quirk handling, timing updates, and using better kernel
     interfaces)
   - eeprom driver can now write with byte-access (very slow, but OK to
     have)
   - and the bunch of smaller fixes, cleanups, ID updates..."

* 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (56 commits)
  i2c: sh_mobile: remove unneeded DMA mask
  i2c: rcar: add slave support
  i2c: slave-eeprom: add eeprom simulator driver
  i2c: core changes for slave support
  MAINTAINERS: add I2C dt bindings also to I2C realm
  i2c: designware: Fix falling time bindings doc
  i2c: davinci: switch to use platform_get_irq
  Documentation: i2c: Use PM ops instead of legacy suspend/resume
  i2c: sh_mobile: optimize irq entry
  i2c: pxa: add support for SCCB devices
  omap: i2c: don't check bus state IP rev3.3 and earlier
  i2c: s3c2410: Handle i2c sys_cfg register in i2c driver
  i2c: rk3x: add Kconfig dependency on COMMON_CLK
  i2c: omap: add notes related to i2c multimaster mode
  i2c: omap: don't reset controller if Arbitration Lost detected
  i2c: omap: implement workaround for handling invalid BB-bit values
  i2c: omap: cleanup register definitions
  i2c: rk3x: handle dynamic clock rate changes correctly
  i2c: at91: enable probe deferring on dma channel request
  i2c: at91: remove legacy DMA support
  ...
2014-12-14 12:54:40 -08:00
Neelesh Gupta
470834508f i2c: Driver to expose PowerNV platform i2c busses
The patch exposes the available i2c busses on the PowerNV platform
to the kernel and implements the bus driver to support i2c and
smbus commands.
The driver uses the platform device infrastructure to probe the busses
on the platform and registers them with the i2c driver framework.

Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de> (I2C part, excluding the bindings)
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-12-14 12:44:46 +11:00
Wolfram Sang
6cf710d476 i2c: sh_mobile: remove unneeded DMA mask
We don't need the mask since we obtain the channels via DT.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11 22:28:22 +01:00
Wolfram Sang
de20d1857d i2c: rcar: add slave support
The first I2C slave provider using the new generic interface.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11 22:25:55 +01:00
Wolfram Sang
389be323cf i2c: slave-eeprom: add eeprom simulator driver
The first user of the i2c-slave interface is an eeprom simulator. It is
a shared memory which can be accessed by the remote master via I2C and
locally via sysfs.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11 22:25:54 +01:00
Wolfram Sang
4b1acc4333 i2c: core changes for slave support
Finally(!), make Linux support being an I2C slave. Most of the existing
infrastructure is reused. We mainly add i2c_slave_register/unregister()
calls which tells i2c bus drivers to activate the slave mode. Then, they
also get a callback to report slave events to.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11 22:25:53 +01:00
Linus Torvalds
7ef58b32f5 Devicetree changes for v3.19
Lots of activity in the devicetree code for v3.18. Most of it is related
 to getting all of the overlay support code in place, but there are other
 important things in there.
 
 There are a few trivial merge conflicts. They shouldn't give you any
 trouble.
 
 Highlights:
 - OF_RECONFIG notifiers for SPI, I2C and Platform devices. Those
   subsystems can now respond to live changes to the device tree.
 - CONFIG_OF_OVERLAY method for applying live changes to the device tree
 - Removal of the of_allnodes list. This used to be used to iterate over
   all the nodes in the device tree, but it is unnecessary because the
   same thing can be done by iterating over the list of child pointers.
   Getting rid of of_allnodes saves some memory and avoids the
   possibility of of_allnodes being sorted differently from the child
   lists.
 - Support for retrieving original DTB blob via sysfs. Needed by kexec.
 - More unittests
 - Documentation and minor bug fixes
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Merge tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux

Pull devicetree changes from Grant Likely:
 "Lots of activity in the devicetree code for v3.18.  Most of it is
  related to getting all of the overlay support code in place, but there
  are other important things in there.

  Highlights:

   - OF_RECONFIG notifiers for SPI, I2C and Platform devices.  Those
     subsystems can now respond to live changes to the device tree.

   - CONFIG_OF_OVERLAY method for applying live changes to the device
     tree

   - Removal of the of_allnodes list.  This used to be used to iterate
     over all the nodes in the device tree, but it is unnecessary
     because the same thing can be done by iterating over the list of
     child pointers.  Getting rid of of_allnodes saves some memory and
     avoids the possibility of of_allnodes being sorted differently from
     the child lists.

   - Support for retrieving original DTB blob via sysfs.  Needed by
     kexec.

   - More unittests

   - Documentation and minor bug fixes"

* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux: (42 commits)
  of: Delete unnecessary check before calling "of_node_put()"
  of: Drop ->next pointer from struct device_node
  spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y
  of: support passing console options with stdout-path
  of: add optional options parameter to of_find_node_by_path()
  of: Add bindings for chosen node, stdout-path
  of: Remove unneeded and incorrect MODULE_DEVICE_TABLE
  ARM: dt: fix up PL011 device tree bindings
  of: base, fix of_property_read_string_helper kernel-doc
  of: remove select of non-existant OF_DEVICE config symbol
  spi/of: Add OF notifier handler
  spi/of: Create new device registration method and accessors
  i2c/of: Add OF_RECONFIG notifier handler
  i2c/of: Factor out Devicetree registration code
  of/overlay: Add overlay unittests
  of/overlay: Introduce DT overlay support
  of/reconfig: Add OF_DYNAMIC notifier for platform_bus_type
  of/reconfig: Always use the same structure for notifiers
  of/reconfig: Add debug output for OF_RECONFIG notifiers
  of/reconfig: Add empty stubs for the of_reconfig methods
  ...
2014-12-11 13:06:58 -08:00
Linus Torvalds
92a578b064 ACPI and power management updates for 3.19-rc1
This time we have some more new material than we used to have during
 the last couple of development cycles.
 
 The most important part of it to me is the introduction of a unified
 interface for accessing device properties provided by platform
 firmware.  It works with Device Trees and ACPI in a uniform way and
 drivers using it need not worry about where the properties come
 from as long as the platform firmware (either DT or ACPI) makes
 them available.  It covers both devices and "bare" device node
 objects without struct device representation as that turns out to
 be necessary in some cases.  This has been in the works for quite
 a few months (and development cycles) and has been approved by
 all of the relevant maintainers.
 
 On top of that, some drivers are switched over to the new interface
 (at25, leds-gpio, gpio_keys_polled) and some additional changes are
 made to the core GPIO subsystem to allow device drivers to manipulate
 GPIOs in the "canonical" way on platforms that provide GPIO information
 in their ACPI tables, but don't assign names to GPIO lines (in which
 case the driver needs to do that on the basis of what it knows about
 the device in question).  That also has been approved by the GPIO
 core maintainers and the rfkill driver is now going to use it.
 
 Second is support for hardware P-states in the intel_pstate driver.
 It uses CPUID to detect whether or not the feature is supported by
 the processor in which case it will be enabled by default.  However,
 it can be disabled entirely from the kernel command line if necessary.
 
 Next is support for a platform firmware interface based on ACPI
 operation regions used by the PMIC (Power Management Integrated
 Circuit) chips on the Intel Baytrail-T and Baytrail-T-CR platforms.
 That interface is used for manipulating power resources and for
 thermal management: sensor temperature reporting, trip point setting
 and so on.
 
 Also the ACPI core is now going to support the _DEP configuration
 information in a limited way.  Basically, _DEP it supposed to reflect
 off-the-hierarchy dependencies between devices which may be very
 indirect, like when AML for one device accesses locations in an
 operation region handled by another device's driver (usually, the
 device depended on this way is a serial bus or GPIO controller).
 The support added this time is sufficient to make the ACPI battery
 driver work on Asus T100A, but it is general enough to be able to
 cover some other use cases in the future.
 
 Finally, we have a new cpufreq driver for the Loongson1B processor.
 
 In addition to the above, there are fixes and cleanups all over the
 place as usual and a traditional ACPICA update to a recent upstream
 release.
 
 As far as the fixes go, the ACPI LPSS (Low-power Subsystem) driver
 for Intel platforms should be able to handle power management of
 the DMA engine correctly, the cpufreq-dt driver should interact
 with the thermal subsystem in a better way and the ACPI backlight
 driver should handle some more corner cases, among other things.
 
 On top of the ACPICA update there are fixes for race conditions
 in the ACPICA's interrupt handling code which might lead to some
 random and strange looking failures on some systems.
 
 In the cleanups department the most visible part is the series
 of commits targeted at getting rid of the CONFIG_PM_RUNTIME
 configuration option.  That was triggered by a discussion
 regarding the generic power domains code during which we realized
 that trying to support certain combinations of PM config options
 was painful and not really worth it, because nobody would use them
 in production anyway.  For this reason, we decided to make
 CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and that lead to the
 conclusion that the latter became redundant and CONFIG_PM could
 be used instead of it.  The material here makes that replacement
 in a major part of the tree, but there will be at least one more
 batch of that in the second part of the merge window.
 
 Specifics:
 
  - Support for retrieving device properties information from ACPI
    _DSD device configuration objects and a unified device properties
    interface for device drivers (and subsystems) on top of that.
    As stated above, this works with Device Trees and ACPI and allows
    device drivers to be written in a platform firmware (DT or ACPI)
    agnostic way.  The at25, leds-gpio and gpio_keys_polled drivers
    are now going to use this new interface and the GPIO subsystem
    is additionally modified to allow device drivers to assign names
    to GPIO resources returned by ACPI _CRS objects (in case _DSD is
    not present or does not provide the expected data).  The changes
    in this set are mostly from Mika Westerberg, Rafael J Wysocki,
    Aaron Lu, and Darren Hart with some fixes from others (Fabio Estevam,
    Geert Uytterhoeven).
 
  - Support for Hardware Managed Performance States (HWP) as described
    in Volume 3, section 14.4, of the Intel SDM in the intel_pstate
    driver.  CPUID is used to detect whether or not the feature is
    supported by the processor.  If supported, it will be enabled
    automatically unless the intel_pstate=no_hwp switch is present in
    the kernel command line.  From Dirk Brandewie.
 
  - New Intel Broadwell-H ID for intel_pstate (Dirk Brandewie).
 
  - Support for firmware interface based on ACPI operation regions
    used by the PMIC chips on the Intel Baytrail-T and Baytrail-T-CR
    platforms for power resource control and thermal management
    (Aaron Lu).
 
  - Limited support for retrieving off-the-hierarchy dependencies
    between devices from ACPI _DEP device configuration objects
    and deferred probing support for the ACPI battery driver based
    on the _DEP information to make that driver work on Asus T100A
    (Lan Tianyu).
 
  - New cpufreq driver for the Loongson1B processor (Kelvin Cheung).
 
  - ACPICA update to upstream revision 20141107 which only affects
    tools (Bob Moore).
 
  - Fixes for race conditions in the ACPICA's interrupt handling
    code and in the ACPI code related to system suspend and resume
    (Lv Zheng and Rafael J Wysocki).
 
  - ACPI core fix for an RCU-related issue in the ioremap() regions
    management code that slowed down significantly after CPUs had
    been allowed to enter idle states even if they'd had RCU callbakcs
    queued and triggered some problems in certain proprietary graphics
    driver (and elsewhere).  The fix replaces synchronize_rcu() in
    that code with synchronize_rcu_expedited() which makes the issue
    go away.  From Konstantin Khlebnikov.
 
  - ACPI LPSS (Low-Power Subsystem) driver fix to handle power
    management of the DMA engine included into the LPSS correctly.
    The problem is that the DMA engine doesn't have ACPI PM support
    of its own and it simply is turned off when the last LPSS device
    having ACPI PM support goes into D3cold.  To work around that,
    the PM domain used by the ACPI LPSS driver is redesigned so at
    least one device with ACPI PM support will be on as long as the
    DMA engine is in use.  From Andy Shevchenko.
 
  - ACPI backlight driver fix to avoid using it on "Win8-compatible"
    systems where it doesn't work and where it was used by default by
    mistake (Aaron Lu).
 
  - Assorted minor ACPI core fixes and cleanups from Tomasz Nowicki,
    Sudeep Holla, Huang Rui, Hanjun Guo, Fabian Frederick, and
    Ashwin Chaugule (mostly related to the upcoming ARM64 support).
 
  - Intel RAPL (Running Average Power Limit) power capping driver
    fixes and improvements including new processor IDs (Jacob Pan).
 
  - Generic power domains modification to power up domains after
    attaching devices to them to meet the expectations of device
    drivers and bus types assuming devices to be accessible at
    probe time (Ulf Hansson).
 
  - Preliminary support for controlling device clocks from the
    generic power domains core code and modifications of the
    ARM/shmobile platform to use that feature (Ulf Hansson).
 
  - Assorted minor fixes and cleanups of the generic power
    domains core code (Ulf Hansson, Geert Uytterhoeven).
 
  - Assorted minor fixes and cleanups of the device clocks control
    code in the PM core (Geert Uytterhoeven, Grygorii Strashko).
 
  - Consolidation of device power management Kconfig options by making
    CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and removing the latter
    which is now redundant (Rafael J Wysocki and Kevin Hilman).  That
    is the first batch of the changes needed for this purpose.
 
  - Core device runtime power management support code cleanup related
    to the execution of callbacks (Andrzej Hajda).
 
  - cpuidle ARM support improvements (Lorenzo Pieralisi).
 
  - cpuidle cleanup related to the CPUIDLE_FLAG_TIME_VALID flag and
    a new MAINTAINERS entry for ARM Exynos cpuidle (Daniel Lezcano and
    Bartlomiej Zolnierkiewicz).
 
  - New cpufreq driver callback (->ready) to be executed when the
    cpufreq core is ready to use a given policy object and cpufreq-dt
    driver modification to use that callback for cooling device
    registration (Viresh Kumar).
 
  - cpufreq core fixes and cleanups (Viresh Kumar, Vince Hsu,
    James Geboski, Tomeu Vizoso).
 
  - Assorted fixes and cleanups in the cpufreq-pcc, intel_pstate,
    cpufreq-dt, pxa2xx cpufreq drivers (Lenny Szubowicz, Ethan Zhao,
    Stefan Wahren, Petr Cvek).
 
  - OPP (Operating Performance Points) framework modification to
    allow OPPs to be removed too and update of a few cpufreq drivers
    (cpufreq-dt, exynos5440, imx6q, cpufreq) to remove OPPs (added
    during initialization) on driver removal (Viresh Kumar).
 
  - Hibernation core fixes and cleanups (Tina Ruchandani and
    Markus Elfring).
 
  - PM Kconfig fix related to CPU power management (Pankaj Dubey).
 
  - cpupower tool fix (Prarit Bhargava).
 
 /
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Merge tag 'pm+acpi-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management updates from Rafael Wysocki:
 "This time we have some more new material than we used to have during
  the last couple of development cycles.

  The most important part of it to me is the introduction of a unified
  interface for accessing device properties provided by platform
  firmware.  It works with Device Trees and ACPI in a uniform way and
  drivers using it need not worry about where the properties come from
  as long as the platform firmware (either DT or ACPI) makes them
  available.  It covers both devices and "bare" device node objects
  without struct device representation as that turns out to be necessary
  in some cases.  This has been in the works for quite a few months (and
  development cycles) and has been approved by all of the relevant
  maintainers.

  On top of that, some drivers are switched over to the new interface
  (at25, leds-gpio, gpio_keys_polled) and some additional changes are
  made to the core GPIO subsystem to allow device drivers to manipulate
  GPIOs in the "canonical" way on platforms that provide GPIO
  information in their ACPI tables, but don't assign names to GPIO lines
  (in which case the driver needs to do that on the basis of what it
  knows about the device in question).  That also has been approved by
  the GPIO core maintainers and the rfkill driver is now going to use
  it.

  Second is support for hardware P-states in the intel_pstate driver.
  It uses CPUID to detect whether or not the feature is supported by the
  processor in which case it will be enabled by default.  However, it
  can be disabled entirely from the kernel command line if necessary.

  Next is support for a platform firmware interface based on ACPI
  operation regions used by the PMIC (Power Management Integrated
  Circuit) chips on the Intel Baytrail-T and Baytrail-T-CR platforms.
  That interface is used for manipulating power resources and for
  thermal management: sensor temperature reporting, trip point setting
  and so on.

  Also the ACPI core is now going to support the _DEP configuration
  information in a limited way.  Basically, _DEP it supposed to reflect
  off-the-hierarchy dependencies between devices which may be very
  indirect, like when AML for one device accesses locations in an
  operation region handled by another device's driver (usually, the
  device depended on this way is a serial bus or GPIO controller).  The
  support added this time is sufficient to make the ACPI battery driver
  work on Asus T100A, but it is general enough to be able to cover some
  other use cases in the future.

  Finally, we have a new cpufreq driver for the Loongson1B processor.

  In addition to the above, there are fixes and cleanups all over the
  place as usual and a traditional ACPICA update to a recent upstream
  release.

  As far as the fixes go, the ACPI LPSS (Low-power Subsystem) driver for
  Intel platforms should be able to handle power management of the DMA
  engine correctly, the cpufreq-dt driver should interact with the
  thermal subsystem in a better way and the ACPI backlight driver should
  handle some more corner cases, among other things.

  On top of the ACPICA update there are fixes for race conditions in the
  ACPICA's interrupt handling code which might lead to some random and
  strange looking failures on some systems.

  In the cleanups department the most visible part is the series of
  commits targeted at getting rid of the CONFIG_PM_RUNTIME configuration
  option.  That was triggered by a discussion regarding the generic
  power domains code during which we realized that trying to support
  certain combinations of PM config options was painful and not really
  worth it, because nobody would use them in production anyway.  For
  this reason, we decided to make CONFIG_PM_SLEEP select
  CONFIG_PM_RUNTIME and that lead to the conclusion that the latter
  became redundant and CONFIG_PM could be used instead of it.  The
  material here makes that replacement in a major part of the tree, but
  there will be at least one more batch of that in the second part of
  the merge window.

  Specifics:

   - Support for retrieving device properties information from ACPI _DSD
     device configuration objects and a unified device properties
     interface for device drivers (and subsystems) on top of that.  As
     stated above, this works with Device Trees and ACPI and allows
     device drivers to be written in a platform firmware (DT or ACPI)
     agnostic way.  The at25, leds-gpio and gpio_keys_polled drivers are
     now going to use this new interface and the GPIO subsystem is
     additionally modified to allow device drivers to assign names to
     GPIO resources returned by ACPI _CRS objects (in case _DSD is not
     present or does not provide the expected data).  The changes in
     this set are mostly from Mika Westerberg, Rafael J Wysocki, Aaron
     Lu, and Darren Hart with some fixes from others (Fabio Estevam,
     Geert Uytterhoeven).

   - Support for Hardware Managed Performance States (HWP) as described
     in Volume 3, section 14.4, of the Intel SDM in the intel_pstate
     driver.  CPUID is used to detect whether or not the feature is
     supported by the processor.  If supported, it will be enabled
     automatically unless the intel_pstate=no_hwp switch is present in
     the kernel command line.  From Dirk Brandewie.

   - New Intel Broadwell-H ID for intel_pstate (Dirk Brandewie).

   - Support for firmware interface based on ACPI operation regions used
     by the PMIC chips on the Intel Baytrail-T and Baytrail-T-CR
     platforms for power resource control and thermal management (Aaron
     Lu).

   - Limited support for retrieving off-the-hierarchy dependencies
     between devices from ACPI _DEP device configuration objects and
     deferred probing support for the ACPI battery driver based on the
     _DEP information to make that driver work on Asus T100A (Lan
     Tianyu).

   - New cpufreq driver for the Loongson1B processor (Kelvin Cheung).

   - ACPICA update to upstream revision 20141107 which only affects
     tools (Bob Moore).

   - Fixes for race conditions in the ACPICA's interrupt handling code
     and in the ACPI code related to system suspend and resume (Lv Zheng
     and Rafael J Wysocki).

   - ACPI core fix for an RCU-related issue in the ioremap() regions
     management code that slowed down significantly after CPUs had been
     allowed to enter idle states even if they'd had RCU callbakcs
     queued and triggered some problems in certain proprietary graphics
     driver (and elsewhere).  The fix replaces synchronize_rcu() in that
     code with synchronize_rcu_expedited() which makes the issue go
     away.  From Konstantin Khlebnikov.

   - ACPI LPSS (Low-Power Subsystem) driver fix to handle power
     management of the DMA engine included into the LPSS correctly.  The
     problem is that the DMA engine doesn't have ACPI PM support of its
     own and it simply is turned off when the last LPSS device having
     ACPI PM support goes into D3cold.  To work around that, the PM
     domain used by the ACPI LPSS driver is redesigned so at least one
     device with ACPI PM support will be on as long as the DMA engine is
     in use.  From Andy Shevchenko.

   - ACPI backlight driver fix to avoid using it on "Win8-compatible"
     systems where it doesn't work and where it was used by default by
     mistake (Aaron Lu).

   - Assorted minor ACPI core fixes and cleanups from Tomasz Nowicki,
     Sudeep Holla, Huang Rui, Hanjun Guo, Fabian Frederick, and Ashwin
     Chaugule (mostly related to the upcoming ARM64 support).

   - Intel RAPL (Running Average Power Limit) power capping driver fixes
     and improvements including new processor IDs (Jacob Pan).

   - Generic power domains modification to power up domains after
     attaching devices to them to meet the expectations of device
     drivers and bus types assuming devices to be accessible at probe
     time (Ulf Hansson).

   - Preliminary support for controlling device clocks from the generic
     power domains core code and modifications of the ARM/shmobile
     platform to use that feature (Ulf Hansson).

   - Assorted minor fixes and cleanups of the generic power domains core
     code (Ulf Hansson, Geert Uytterhoeven).

   - Assorted minor fixes and cleanups of the device clocks control code
     in the PM core (Geert Uytterhoeven, Grygorii Strashko).

   - Consolidation of device power management Kconfig options by making
     CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and removing the latter
     which is now redundant (Rafael J Wysocki and Kevin Hilman).  That
     is the first batch of the changes needed for this purpose.

   - Core device runtime power management support code cleanup related
     to the execution of callbacks (Andrzej Hajda).

   - cpuidle ARM support improvements (Lorenzo Pieralisi).

   - cpuidle cleanup related to the CPUIDLE_FLAG_TIME_VALID flag and a
     new MAINTAINERS entry for ARM Exynos cpuidle (Daniel Lezcano and
     Bartlomiej Zolnierkiewicz).

   - New cpufreq driver callback (->ready) to be executed when the
     cpufreq core is ready to use a given policy object and cpufreq-dt
     driver modification to use that callback for cooling device
     registration (Viresh Kumar).

   - cpufreq core fixes and cleanups (Viresh Kumar, Vince Hsu, James
     Geboski, Tomeu Vizoso).

   - Assorted fixes and cleanups in the cpufreq-pcc, intel_pstate,
     cpufreq-dt, pxa2xx cpufreq drivers (Lenny Szubowicz, Ethan Zhao,
     Stefan Wahren, Petr Cvek).

   - OPP (Operating Performance Points) framework modification to allow
     OPPs to be removed too and update of a few cpufreq drivers
     (cpufreq-dt, exynos5440, imx6q, cpufreq) to remove OPPs (added
     during initialization) on driver removal (Viresh Kumar).

   - Hibernation core fixes and cleanups (Tina Ruchandani and Markus
     Elfring).

   - PM Kconfig fix related to CPU power management (Pankaj Dubey).

   - cpupower tool fix (Prarit Bhargava)"

* tag 'pm+acpi-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (120 commits)
  i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c
  dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  tools: cpupower: fix return checks for sysfs_get_idlestate_count()
  drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME
  MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  leds: leds-gpio: Fix multiple instances registration without 'label' property
  iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hwrandom / exynos / PM: Use CONFIG_PM in #ifdef
  block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  USB / PM: Drop CONFIG_PM_RUNTIME from the USB core
  PM: Merge the SET*_RUNTIME_PM_OPS() macros
  ...
2014-12-10 21:17:00 -08:00
Linus Torvalds
3a7dbed7f2 Hi Linus,
Changes to the core:
  - Honour PLATFORM_DEVID_NONE and PLATFORM_DEVID_AUTO dev IDs
 
 Changes to existing drivers:
  - IRQ additions/fixes; axp20x, da9063-core
  - Code simplification; i2c-dln2
  - Regmap additions/fixes; max77693
  - Error checking/handling improvements; dln2, db8500-prcmu
  - Bug fixes; dln2, wm8350-core
  - DT support/documentation; max77693, max77686, tps65217, twl4030-power,
                              gpio-tc3589x
  - Decouple syscon interface from platform devices
  - Use MFD hotplug registration; rtsx_usb, viperboard, hid-sensor-hub
  - Regulator fixups; sec-core
  - Power Management additions/fixes; rts5227, tc6393xb
  - Remove relic/redundant code; ab8500-sysctrl, lpc_sch, max77693-private
  - Clean-up/coding style changes; tps65090
  - Clk additions/fixes; tc6393xb, tc6387xb, t7l66xb
  - Add USB-SPI support; dln2
  - Trivial changes; max14577, arizona-spi, lpc_sch, wm8997-tables, wm5102-tables
                     wm5110-tables, axp20x, atmel-hlcdc, rtsx_pci
 
 New drivers/supported devices:
  - axp288 PMIC support added to axp20x
  - s2mps13 support added to sec-core
  - New support for Diolan DLN-2
  - New support for atmel-hlcdc
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Merge tag 'mfd-for-linus-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd

Pull MFD updates from Lee Jones:
 "Changes to the core:
   - Honour PLATFORM_DEVID_NONE and PLATFORM_DEVID_AUTO dev IDs

  Changes to existing drivers:
   - IRQ additions/fixes; axp20x, da9063-core
   - Code simplification; i2c-dln2
   - Regmap additions/fixes; max77693
   - Error checking/handling improvements; dln2, db8500-prcmu
   - Bug fixes; dln2, wm8350-core
   - DT support/documentation; max77693, max77686, tps65217, twl4030-power,
                               gpio-tc3589x
   - Decouple syscon interface from platform devices
   - Use MFD hotplug registration; rtsx_usb, viperboard, hid-sensor-hub
   - Regulator fixups; sec-core
   - Power Management additions/fixes; rts5227, tc6393xb
   - Remove relic/redundant code; ab8500-sysctrl, lpc_sch, max77693-private
   - Clean-up/coding style changes; tps65090
   - Clk additions/fixes; tc6393xb, tc6387xb, t7l66xb
   - Add USB-SPI support; dln2
   - Trivial changes; max14577, arizona-spi, lpc_sch, wm8997-tables, wm5102-tables
                      wm5110-tables, axp20x, atmel-hlcdc, rtsx_pci

  New drivers/supported devices:
   - axp288 PMIC support added to axp20x
   - s2mps13 support added to sec-core
   - New support for Diolan DLN-2
   - New support for atmel-hlcdc"

* tag 'mfd-for-linus-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (55 commits)
  mfd: rtsx: Add func to split u32 into register
  mfd: atmel-hlcdc: Add Kconfig option description and name
  mfd: da9063: Get irq base dynamically before registering device
  mfd: max14577: Fix obvious typo in company name in copyright
  mfd: axp20x: Constify axp20x_acpi_match and rid unused warning
  mfd: t7l66xb: prepare/unprepare clocks
  mfd: tc6387xb: prepare/unprepare clocks
  mfd: dln2: add support for USB-SPI module
  mfd: wm5110: Add missing registers for AIF2 channels 3-6
  mfd: tc3589x: get rid of static base
  mfd: arizona: Document HP_CTRL_1L and HP_CTRL_1R registers
  mfd: wm8997: Mark INTERRUPT_STATUS_2_MASK as readable
  mfd: tc6393xb: Prepare/unprepare clocks
  mfd: tps65090: Fix bonkers indenting strategy
  mfd: tc6393xb: Fail ohci suspend if full state restore is required
  mfd: lpc_sch: Don't call mfd_remove_devices()
  mfd: wm8350-core: Fix probable mask then right shift defect
  mfd: ab8500-sysctrl: Drop ab8500_restart
  mfd: db8500-prcmu: Provide sane error path values
  mfd: db8500-prcmu: Check return of devm_ioremap for error
  ...
2014-12-08 20:02:54 -08:00
Rafael J. Wysocki
e3d857e1ae Merge branch 'pm-runtime'
* pm-runtime: (25 commits)
  i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c
  dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME
  MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hwrandom / exynos / PM: Use CONFIG_PM in #ifdef
  block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  USB / PM: Drop CONFIG_PM_RUNTIME from the USB core
  PM: Merge the SET*_RUNTIME_PM_OPS() macros
  PM / Kconfig: Do not select PM directly from Kconfig files
  PCI / PM: Drop CONFIG_PM_RUNTIME from the PCI core
  ...
2014-12-08 20:00:44 +01:00
Rafael J. Wysocki
69bad361e6 Merge branches 'acpi-scan', 'acpi-pm', 'acpi-lpss' and 'acpi-processor'
* acpi-scan:
  ACPI: Add _DEP support to fix battery issue on Asus T100TA

* acpi-pm:
  ACPI / sleep: Drain outstanding events after disabling multiple GPEs
  ACPI / PM: Fixed a typo in a comment

* acpi-lpss:
  dmaengine: dw: enable runtime PM
  ACPI / LPSS: introduce a 'proxy' device to power on LPSS for DMA
  ACPI / LPSS: allow to use specific PM domain during ->probe()
  ACPI / LPSS: add all LPSS devices to the specific power domain

* acpi-processor:
  ACPI / cpuidle: avoid assigning signed errno to acpi_status
  ACPI / processor: remove unused variabled from acpi_processor_power structure
  ACPI / processor: Update the comments in processor.h
2014-12-08 19:52:16 +01:00
Rafael J. Wysocki
2713775bf5 i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so some #ifdef blocks
depending on CONFIG_PM_RUNTIME may be dropped now.

Do that in drivers/i2c/busses/i2c-omap.c.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-05 23:32:11 +01:00
Vishnu Motghare
681d15a0f5 i2c: cadence: Set the hardware time-out register to maximum value
Cadence I2C controller has bug wherein it generates invalid read transactions
after timeout in master receiver mode. This driver does not use the HW
timeout and this interrupt is disabled but the feature itself cannot be
disabled. Hence, this patch writes the maximum value (0xFF) to this register.
This is one of the workarounds to this bug and it will not avoid the issue
completely but reduces the chances of error.

Signed-off-by: Vishnu Motghare <vishnum@xilinx.com>
Signed-off-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-12-04 19:25:41 +01:00
Grygorii Strashko
9ea359f731 i2c: davinci: generate STP always when NACK is received
According to I2C specification the NACK should be handled as follows:
"When SDA remains HIGH during this ninth clock pulse, this is defined as the Not
Acknowledge signal. The master can then generate either a STOP condition to
abort the transfer, or a repeated START condition to start a new transfer."
[I2C spec Rev. 6, 3.1.6: http://www.nxp.com/documents/user_manual/UM10204.pdf]

Currently the Davinci i2c driver interrupts the transfer on receipt of a
NACK but fails to send a STOP in some situations and so makes the bus
stuck until next I2C IP reset (idle/enable).

For example, the issue will happen during SMBus read transfer which
consists from two i2c messages write command/address and read data:

S Slave Address Wr A Command Code A Sr Slave Address Rd A D1..Dn A P
<--- write -----------------------> <--- read --------------------->

The I2C client device will send NACK if it can't recognize "Command Code"
and it's expected from I2C master to generate STP in this case.
But now, Davinci i2C driver will just exit with -EREMOTEIO and STP will
not be generated.

Hence, fix it by generating Stop condition (STP) always when NACK is received.

This patch fixes Davinci I2C in the same way it was done for OMAP I2C
commit cda2109a26 ("i2c: omap: query STP always when NACK is received").

Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reported-by: Hein Tibosch <hein_tibosch@yahoo.es>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-12-04 19:25:31 +01:00
Grygorii Strashko
2c6ef04ffa i2c: davinci: switch to use platform_get_irq
Switch Davinci I2C driver to use platform_get_irq(), because
it is not recommened to use platform_get_resource(pdev, IORESOURCE_IRQ, ..)
for requesting IRQ resources any more, as they can be not ready yet
in case of DT-boot.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-04 19:15:08 +01:00
Wolfram Sang
530834b13f i2c: sh_mobile: optimize irq entry
We can simply pass the pointer to the private structure to the irq
routine instead of passing the platform device and looking up its
driver_data.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-04 18:49:54 +01:00
Rafael J. Wysocki
6ed23b806e PM: Merge the SET*_RUNTIME_PM_OPS() macros
The SET_PM_RUNTIME_PM_OPS() and SET_RUNTIME_PM_OPS() macros are
identical except that one of them is not empty for CONFIG_PM set,
while the other one is not empty for CONFIG_PM_RUNTIME set,
respectively.

However, after commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if
PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so one
of these macros is now redundant.

For this reason, replace SET_PM_RUNTIME_PM_OPS() with
SET_RUNTIME_PM_OPS() everywhere and redefine the SET_PM_RUNTIME_PM_OPS
symbol as SET_RUNTIME_PM_OPS in case new code is starting to use the
macro being removed here.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-04 00:51:30 +01:00
Petr Cvek
86261fdd65 i2c: pxa: add support for SCCB devices
Add support for SCCB by implementing I2C_M_IGNORE_NAK and I2C_M_STOP
flags and advertising functionality flag I2C_FUNC_PROTOCOL_MANGLING.

Also fixed missing functionality flag I2C_FUNC_NOSTART.

Signed-off-by: Petr Cvek <petr.cvek@tul.cz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-25 21:32:26 +01:00
Alexander Kochetkov
23173eae7b omap: i2c: don't check bus state IP rev3.3 and earlier
Commit 0f5768bf89 ("i2c: omap: implement workaround for handling
invalid BB-bit values") introduce the error result in boot test fault on
OMAP3530 boards.

The patch fix the error (disable i2c bus test for OMAP3530).

Reported-by: Kevin Hilman <khilman@kernel.org>
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Fixes: 0f5768bf89 ("i2c: omap: implement workaround for handling invalid BB-bit values")
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-25 21:31:31 +01:00
Pantelis Antoniou
ea7513bbc0 i2c/of: Add OF_RECONFIG notifier handler
CONFIG_OF_DYNAMIC enables runtime changes to the device tree which in
turn may trigger addition or removal of devices from Linux. Add an
OF_RECONFIG notifier handler to receive tree change events and to
creating or destroy i2c devices as required.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: clean up #ifdefs and drop unneeded error handling]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-i2c@vger.kernel.org
2014-11-25 15:35:35 +00:00
Pantelis Antoniou
a430a3455f i2c/of: Factor out Devicetree registration code
Dynamically inserting i2c client device nodes requires the use
of a single device registration method. Factor out the loop body of
of_i2c_register_devices() so that it can be called for individual
device_nodes instead of for all the children of a node.

Note: The diff of this commit looks far more complicated than it
actually is due the indentation being changed for a large block of code.
When viewed using the diff -w flag to ignore whitespace changes it can
be seen that the change is actually quite simple.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Made new function static and removed changes to header]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-i2c@vger.kernel.org
2014-11-25 15:35:16 +00:00
Pankaj Dubey
a7750c3ef0 i2c: s3c2410: Handle i2c sys_cfg register in i2c driver
Let's handle i2c interrupt re-configuration in i2c driver. This will
help us in removing some soc specific checks from machine files and
will help in removing static iomapping of SYS register in exynos.c

Also handle saving and restoring of SYS_I2C_CFG register during
suspend and resume of i2c driver.

Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-24 10:37:14 +01:00
Max Schwarz
80f1774f96 i2c: rk3x: add Kconfig dependency on COMMON_CLK
Now that we are using the clk notifier framework we get compile errors
without COMMON_CLK. But the driver fails to probe without COMMON_CLK
anyways, so just add that as a Kconfig dependency.

Signed-off-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-24 10:28:32 +01:00
Lan Tianyu
40e7fcb192 ACPI: Add _DEP support to fix battery issue on Asus T100TA
ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate
device objects that OSPM should assign a higher priority in start
ordering due to future operation region accesses.

On Asus T100TA, ACPI battery info are read from a I2C slave device via
I2C operation region. Before I2C operation region handler is installed,
battery _STA always returns 0. There is a _DEP method of designating
start order under battery device node.

This patch is to implement _DEP feature to fix battery issue on the
Asus T100TA.  Introducing acpi_dep_list and adding dep_unmet count
in struct acpi_device. During ACPI namespace scan, create struct
acpi_dep_data for a valid pair of master (device pointed to by _DEP)/
slave(device with _DEP), record master's and slave's ACPI handle in
it and put it into acpi_dep_list. The dep_unmet count will increase
by one if there is a device under its _DEP. Driver's probe() should
return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C
operation region handler is installed, remove all struct acpi_dep_data
on the acpi_dep_list whose master is pointed to I2C host controller
and decrease slave's dep_unmet. When dep_unmet decreases to 0, all
_DEP conditions are met and then do acpi_bus_attach() for the device
in order to resolve battery _STA issue on the Asus T100TA.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011
Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org>
Tested-by: Adam Williamson <adamw@happyassassin.net>
Tested-by: Michael Shigorin <shigorin@gmail.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-24 01:04:55 +01:00
Alexander Kochetkov
4f734a3a04 i2c: omap: add notes related to i2c multimaster mode
No functional changes.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23 17:27:49 +01:00
Alexander Kochetkov
b76911d2fe i2c: omap: don't reset controller if Arbitration Lost detected
Arbitration Lost is an expected situation in a multimaster
environment. I2C controller (IP) correctly detect and report AL.

The only one visible reason for resetting IP in the AL case is
to avoid advisory 1.94 (omap3) and errata i595 (omap4): "I2C:
After an Arbitration is Lost the Module Incorrectly Starts
the Next Transfer".

Errata workaround states: "The MST and STT bits inside I2C_CON
should be set to 1 at the same moment (avoid setting the MST bit
to 1 while STT = 0)." The driver never set MST and STT bits
separately and doesn't create condition for errata. So the reset
is not necessary.

Also corrected return value for AL to -EAGAIN.

Tested on Beagleboard XM C.
Tested on BBB and AM437x Starter Kit by Felipe Balbi.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23 17:27:48 +01:00
Alexander Kochetkov
0f5768bf89 i2c: omap: implement workaround for handling invalid BB-bit values
In a multimaster environment, after IP software reset, BB-bit value doesn't
correspond to the current bus state. It may happen what BB-bit will be 0,
while the bus is busy due to another I2C master activity.

Any transfer started when BB=0 and bus is busy wouldn't be completed by IP
and results in controller timeout. More over, in some cases IP could
interrupt another master's transfer and corrupt data on wire.

The commit implement method allowing to prevent IP from entering into
"controller timeout" state and from "data corruption" state.

The one drawback is the need to wait for 10ms before the first transfer.

Tested on Beagleboard XM C.
Tested on BBB and AM437x Starter Kit by Felipe Balbi.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23 17:27:47 +01:00
Alexander Kochetkov
9fd6ada84f i2c: omap: cleanup register definitions
Delete STAT_AD0 mask as unrelated to current IP (omap1?).
Delete DEBUG conditional around SYSTEST masks group.
Add SYSTEST functional mode masks for SCL and SDA.
Add STAT_BF mask.

Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23 17:27:47 +01:00