The current SMBus Host Notify implementation relies on .alert() to
relay its notifications. However, the use cases where SMBus Host
Notify is needed currently is to signal data ready on touchpads.
This is closer to an IRQ than a custom API through .alert().
Given that the 2 touchpad manufacturers (Synaptics and Elan) that
use SMBus Host Notify don't put any data in the SMBus payload, the
concept actually matches one to one.
Benefits are multiple:
- simpler code and API: the client will just have an IRQ, and
nothing needs to be added in the adapter beside internally
enabling it.
- no more specific workqueue, the threading is handled by IRQ core
directly (when required)
- no more races when removing the device (the drivers are already
required to disable irq on remove)
- simpler handling for drivers: use plain regular IRQs
- no more dependency on i2c-smbus for i2c-i801 (and any other adapter)
- the IRQ domain is created automatically when the adapter exports
the Host Notify capability
- the IRQ are assign only if ACPI, OF and the caller did not assign
one already
- the domain is automatically destroyed on remove
- fewer lines of code (minus 20, yeah!)
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Device driver for Mellanox I2C controller logic, implemented in Lattice
CPLD device.
Device supports:
- Master mode
- One physical bus
- Polling mode
The Kconfig currently controlling compilation of this code is:
drivers/i2c/busses/Kconfig:config I2C_MLXCPLD
Signed-off-by: Michael Shych <michaelsh@mellanox.com>
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Make it clear that adding slave support shall not disable master
functionality. We can have both, so we should.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
SMBus Host Notify allows a slave device to act as a master on a bus to
notify the host of an interrupt. On Intel chipsets, the functionality
is directly implemented in the firmware. We just need to export a
function to call .alert() on the proper device driver.
i2c_handle_smbus_host_notify() behaves like i2c_handle_smbus_alert().
When called, it schedules a task that will be able to sleep to go through
the list of devices attached to the adapter.
The current implementation allows one Host Notification to be scheduled
while an other is running.
Tested-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The root i2c adapter lock is then no longer held by the i2c mux during
accesses behind the i2c gate, and such accesses need to take that lock
just like any other ordinary i2c accesses do.
So, declare the i2c gate mux-locked, and zap the regmap overrides
that makes the i2c accesses unlocked and use plain old regmap
accesses. This also removes the need for the regmap wrappers used by
rtl2832_sdr, so deconvolute the code further and provide the regmap
handle directly instead of the wrapper functions.
Tested-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The root i2c adapter lock is then no longer held by the i2c mux during
accesses behind the i2c gate, and such accesses need to take that lock
just like any other ordinary i2c accesses do.
So, declare the i2c gate mux-locked, and zap the code that makes the
i2c accesses unlocked. But add a mutex so that firmware commands are
still serialized.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The root i2c adapter lock is then no longer held by the i2c mux during
accesses behind the i2c gate, and such accesses need to take that lock
just like any other ordinary i2c accesses do.
So, declare the i2c gate mux-locked, and zap the code that makes the
unlocked i2c accesses and just use ordinary regmap_write accesses.
This also happens to fix the deadlock described in
http://patchwork.ozlabs.org/patch/584776/ authored by
Adriana Reus <adriana.reus@intel.com> and submitted by
Daniel Baluta <daniel.baluta@intel.com>
----------8<----------
iio: imu: inv_mpu6050: Fix deadlock between i2c adapter lock and mpu lock
This deadlock occurs if the accel/gyro and the sensor on the auxiliary
I2C (in my setup it's an ak8975) are working at the same time.
Scenario:
T1 T2
==== ====
inv_mpu6050_read_fifo aux sensor op (eg. ak8975_read_raw)
| |
mutex_lock(&indio_dev->mlock) i2c_transfer
| |
i2c transaction i2c adapter lock
| |
i2c adapter lock i2c_mux_master_xfer
|
inv_mpu6050_select_bypass
|
mutex_lock(&indio_dev->mlock)
When we operate on an mpu sensor the order of locking is mpu lock
followed by the i2c adapter lock. However, when we operate the auxiliary
sensor the order of locking is the other way around.
...
----------8<----------
The reason this patch fixes the deadlock is that T2 does not grab the
i2c adapter lock until the very end (and grabs the newfangled i2c mux
lock where it previously grabbed the i2c adapter lock).
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Tested-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This path fix spelling typos found in Documentation/i2c.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Add missing entries into i2c-i801 documentation and Kconfig about recently
added Intel DNV and Broxton.
Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We now have seperate address spaces for 10 bit and we-are-slave clients.
Update the sysfs device instantiation method to support these types by
accepting the address offsets that are assigned to the extra address
spaces. Update the documentation, too.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add support for VCT-jig parallel port I2C adapter to i2c-parport.
The adapter schematic can be found here (in the RAR file):
http://remont-aud.net/shop/22/desc/vct-jig-komplekt-dlja-samostojatelnoj-sborki
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
"Highlights:
- new drivers for Mediatek I2C, APM X-Gene, Broadcom Settop
- major updates to at91, davinci
- bugfixes to the mux infrastructure when dealing with the new quirk
mechanism
- more users for the bus recovery feature
- further improvements to the slave framework
Plus the usual bunch of smaller driver and core improvements and
fixes.
There is one patch removing old code from an ARM platform. This has
been acked by the sh_mobile maintainer Simon Horman"
* 'i2c/for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (48 commits)
i2c: busses: i2c-bcm2835: limits cdiv to allowed values
i2c: sh_mobile: use proper type for timeout
i2c: sh_mobile: use adapter default for timeout
i2c: rcar: use proper type for timeout
i2c: rcar: use adapter default for timeout
i2c: designware: Make sure the device is suspended before disabling runtime PM
i2c: tegra: apply size limit quirk
i2c: tegra: don't advertise SMBUS_QUICK
i2c: octeon: remove unused signal handling
i2c: davinci: Optimize SCL generation
i2c: mux: pca954x: Use __i2c_transfer because of quirks
i2c: mux: Use __i2c_transfer() instead of calling parent's master_xfer()
i2c: use parent adapter quirks in mux
i2c: bcm2835: clear reserved bits in S-Register
ARM: shmobile: r8a7740: remove I2C errata handling
i2c: sh_mobile: add errata workaround
i2c: at91: fix code checker warnings
i2c: busses: xgene-slimpro: fix incorrect __init declation for probe
i2c: davinci: Avoid sending to own address
i2c: davinci: Refactor i2c_davinci_wait_bus_not_busy()
...
I copied the wrong shell code into the documentation. Sorry to all who
tried to get sense out of this current example :/ Slight rewording while
we are here.
Reported-by: Tim Bakker <bakkert@mymail.vcu.edu>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
There was some confusion what was needed to utilize the slave support,
so let's be more precise about this. Add an introductory paragraph to
the development section while we are here.
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>
Since commit 607ca46e97 ('UAPI: (Scripted) Disintegrate include/linux') the
list of functionality constants moved to include/uapi/linux/i2c.h. Update the
reference accordingly.
Fixes: 607ca46e97 ('UAPI: (Scripted) Disintegrate include/linux')
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
New drivers should use PM ops instead of the legacy suspend/resume
callbacks. Update the I2C device driver guides to reflect this.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds the I2C/SMBus Device IDs for the Intel Sunrise Point PCH.
Signed-off-by: James Ralston <james.d.ralston@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The example code provided with the i2c device interface documentation
won't compile since it uses the reserved word "register" to name a
variable.
The compiler fails with this error message:
error: expected identifier or '(' before '=' token
__u8 register = 0x20; /* Device register to access */
^
Rename the variable "register" to simply "reg" in the example code.
Another couple of typos has been fixed as well.
[Change "! =" to "!=".]
Signed-off-by: Jose Alarcon Roldan <jose.alarcon.roldan@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some chips implement banked register ranges. This allows implementing
more registers than the limited 8-bit address space originally allows.
In order to access a register on these chips, you must first select
the proper bank. Add support for this mechanism to the i2c-stub driver
so that such chips can be emulated. All the bank settings are passed
as module parameters.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
SMBus block commands are different to I2C block commands since
the returned data is not normally accessible with byte or word
commands on other command offsets. Add linked list of 'block'
commands to support those commands.
Access mechanism is quite simple: Block commands must be written
before they can be read. Subsequent writes can be partial. Block
read commands always return the number of bytes associated with
the longest previous write.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Sort the entries alphabetically. Make the introductory paragraph more
precise. Skip useless 'Flag' introduction from the entries. Remove
trailing white spaces from the file. Add missing I2C_M_STOP entry.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add Device ID of Intel BayTrail SMBus Controller.
Signed-off-by: Chew, Kean ho <kean.ho.chew@intel.com>
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull more i2c updates from Wolfram Sang:
"Mostly bugfixes, small but wanted cleanups, and Paul's init.h removal
applied"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: rcar: fix NACK error code
i2c: update i2c_algorithm documentation
i2c: rcar: use devm_clk_get to ensure clock is properly ref-counted
i2c: rcar: do not print error if device nacks transfer
i2c: rely on driver core when sanitizing devices
i2c: delete non-required instances of include <linux/init.h>
i2c: acorn: is tristate and should use module.h
i2c: piix4: Standardize log messages
i2c: piix4: Use different message for AMD Auxiliary SMBus Controller
i2c: piix4: Add support for AMD ML and CZ SMBus changes
Pull hwmon updates from Jean Delvare:
"This include it87 driver improvements, and a tree-wide change of my
e-mail address"
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
Update Jean Delvare's e-mail address
hwmon: (it87) Print proper names for the IT8771E and IT8772E
hwmon: (it87) Add support for the ITE IT8603E
The locations of SMBus register base address and enablement bit are changed
from AMD ML, which need this patch to be supported.
Signed-off-by: Shane Huang <shane.huang@amd.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org
Documentation/i2c/fault-codes illustrates EINVAL error code
as follows:
"One example would be a driver trying an SMBus Block Write
with block size outside the range of 1-32 bytes."
However, the actual implementation of i2c subsystem truncates
data length to be 32 bytes.
Hence this example cannot happen anymore, and since it's obsolete,
let's simply remove it from Documentation/i2c/fault-codes.
Signed-off-by: Helia Correia <helia.correia@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds the SMBus Device IDs for the Intel Wildcat Point-LP PCH.
Signed-off-by: James Ralston <james.d.ralston@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull trivial tree from Jiri Kosina:
"The usual trivial updates all over the tree -- mostly typo fixes and
documentation updates"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (52 commits)
doc: Documentation/cputopology.txt fix typo
treewide: Convert retrun typos to return
Fix comment typo for init_cma_reserved_pageblock
Documentation/trace: Correcting and extending tracepoint documentation
mm/hotplug: fix a typo in Documentation/memory-hotplug.txt
power: Documentation: Update s2ram link
doc: fix a typo in Documentation/00-INDEX
Documentation/printk-formats.txt: No casts needed for u64/s64
doc: Fix typo "is is" in Documentations
treewide: Fix printks with 0x%#
zram: doc fixes
Documentation/kmemcheck: update kmemcheck documentation
doc: documentation/hwspinlock.txt fix typo
PM / Hibernate: add section for resume options
doc: filesystems : Fix typo in Documentations/filesystems
scsi/megaraid fixed several typos in comments
ppc: init_32: Fix error typo "CONFIG_START_KERNEL"
treewide: Add __GFP_NOWARN to k.alloc calls with v.alloc fallbacks
page_isolation: Fix a comment typo in test_pages_isolated()
doc: fix a typo about irq affinity
...
__initdata should be placed between the variable name and equal
sign for the variable to be placed in the intended section.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add support for the secondary SMBus controller on the AMD SB800 and AMD FCH
chipsets.
Signed-off-by: Rudolf Marek <r.marek@assembler.cz>
Tested-by: Paul Menzel <paulepanter@users.sourceforge.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
- new drivers: Kontron PLD, Wondermedia VT
- mv64xxx driver gained sun4i support and a bigger cleanup
- duplicate driver 'intel-mid' removed
- added generic device tree binding for sda holding time (and
designware driver already uses it)
- we tried to allow driver probing with only device tree and no i2c
ids, but I had to revert it because of side effects. Needs some
rethinking.
- driver bugfixes, cleanups...
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (34 commits)
i2c-designware: use div_u64 to fix link
i2c: Kontron PLD i2c bus driver
i2c: iop3xxx: fix build failure after waitqueue changes
i2c-designware: make SDA hold time configurable
i2c: mv64xxx: Set bus frequency to 100kHz if clock-frequency is not provided
i2c: imx: allow autoloading on dt ids
i2c: mv64xxx: Fix transfer error code
i2c: i801: SMBus patch for Intel Coleto Creek DeviceIDs
i2c: omap: correct usage of the interrupt enable register
i2c-pxa: prepare clock before use
Revert "i2c: core: make it possible to match a pure device tree driver"
i2c: nomadik: allocate adapter number dynamically
i2c: nomadik: support elder Nomadiks
i2c: mv64xxx: Add Allwinner sun4i compatible
i2c: mv64xxx: make the registers offset configurable
i2c: mv64xxx: Add macros to access parts of registers
i2c: vt8500: Add support for I2C bus on Wondermedia SoCs
i2c: designware: fix race between subsequent xfers
i2c: bfin-twi: Read and write the FIFO in loop
i2c: core: make it possible to match a pure device tree driver
...
This patch adds the i801 SMBus Controller DeviceIDs for the Intel Coleto Creek PCH.
Signed-off-by: Seth Heasley <seth.heasley@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds the SMBus Device IDs for the Intel Wellsburg PCH
Signed-off-by: James Ralston <james.d.ralston@intel.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
The iSMT (Intel SMBus Message Transport) supports multi-master I2C/SMBus,
as well as IPMI. It's operation is DMA-based and utilizes descriptors to
initiate transactions on the bus.
The iSMT hardware can act as both a master and a target, although this
driver only supports being a master.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Bill Brown <bill.e.brown@intel.com>
Tested-by: Seth Heasley <seth.heasley@intel.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
