Add i2c support for the on-board PLD found on some Kontron embedded
modules.
Originally-From: Michael Brunner <michael.brunner@kontron.com>
Signed-off-by: Kevin Strasser <kevin.strasser@linux.intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There has long been a syntax problem in iop3xx_i2c_wait_event() which
has been somehow hidden by the macros in <linux/wait.h>. After some
recent cleanup/rework of the wait_event_* helpers, the bug has come
out from hiding and now results in build failure:
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c: In function 'iop3xx_i2c_wait_event':
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:143: error: expected ')' before ';' token
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:157: error: expected ')' before ';' token
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:213: error: expected ')' before ';' token
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:291: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:551: error: expected ')' before ';' token
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:565: error: expected ')' before ';' token
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:764: error: expected ')' before ';' token
/work/kernel/next/drivers/i2c/busses/i2c-iop3xx.c:176:778: error: expected ')' b
Fix by removing stray ';'
Signed-off-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch makes the SDA hold time configurable through device tree.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com> for arch/arc bits
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In case of collision on i2c bus the controller which lost bus mastership
stays as a slave for all subsequent transfers. This results in the i2c
controller never writing to the bus for future transactions, resulting
in i2c transfer timeouts.
This fix checks for a collision on last I2C transaction and sets the
I2COM_MASTER bit for the new transaction.
Signed-off-by: Sachin Surendran <sachin.surendran@alliedtelesis.co.nz>
Signed-off-by: Scott Wood <scottwood@freescale.com>
This commit adds checking whether clock-frequency property acquisition
has succeeded. If not, the frequency is set to 100kHz by default.
The Device Tree binding documentation is updated accordingly.
Based on the intials patches from Zbigniew Bodek
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Zbigniew Bodek <zbb@semihalf.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Allow udev to autoload the module when booting with device-tree
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The driver returns -ENODEV as error code if it did not get an ACK
from the device. Per Documentation/i2c/fault-codes, it should
return -ENXIO.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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>
- Add devicetree support to timer, pinctrl (probe), I2C block,
watchdog, DMA controller and clocks.
- Piecewise add a device tree containing all peripherals.
- Delete the ATAG boot path.
- Delete redundant platform data and board files.
- Convert to multiplatform.
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Merge tag 'u300-multiplatform' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson into next/soc
From Linus Walleij:
Device Tree and Multiplatform support for U300:
- Add devicetree support to timer, pinctrl (probe), I2C block,
watchdog, DMA controller and clocks.
- Piecewise add a device tree containing all peripherals.
- Delete the ATAG boot path.
- Delete redundant platform data and board files.
- Convert to multiplatform.
* tag 'u300-multiplatform' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson: (40 commits)
ARM: u300: switch to using syscon regmap for board
ARM: u300: Update MMC configs for u300 defconfig
spi: pl022: use DMA by default when probing from DT
pinctrl: get rid of all platform data for coh901
ARM: u300: convert MMC/SD clock to device tree
ARM: u300: move the gated system controller clocks to DT
i2c: stu300: do not request a specific clock name
clk: move the U300 fixed and fixed-factor to DT
ARM: u300: remove register definition file
ARM: u300: add syscon node
ARM: u300 use module_spi_driver to register driver
ARM: u300: delete remnant machine headers
ARM: u300: convert to multiplatform
ARM: u300: localize <mach/u300-regs.h>
ARM: u300: delete <mach/irqs.h>
ARM: u300: delete <mach/hardware.h>
ARM: u300: push down syscon registers
ARM: u300: remove deps from debug macro
ARM: u300: move debugmacro to debug includes
ARM: u300: delete all static board data
...
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
I got a build error today that made me realize that it is not
possible to build a kernel for a SiRF platform without enabling
CONFIG_PRIMA2, since a lot of common code depends on CONFIG_PRIMA2.
This fixes all occurences that appear like common SiRF code.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mark Brown <broonie@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Barry Song <Baohua.Song@csr.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
We've been lucky not to have any interrupts fire during the suspend
path, otherwise we would have unpredictable behaviour in the kernel.
Based on the logic of the kernel code interrupts from i2c should be
prohibited during suspend. Kernel writes 0 to the I2C_IE register in
the omap_i2c_runtime_suspend() function. In the other side kernel
writes saved interrupt flags to the I2C_IE register in
omap_i2c_runtime_resume() function. I.e. interrupts should be disabled
during suspend.
This works for chips with version1 registers scheme. Interrupts are
disabled during suspend. For chips with version2 scheme registers
writting 0 to the I2C_IE register does nothing (because now the
I2C_IRQENABLE_SET register is located at this address). This register
is used to enable interrupts. For disabling interrupts
I2C_IRQENABLE_CLR register should be used.
Because the registers I2C_IRQENABLE_SET and I2C_IE have the same
addresses, the interrupt enabling procedure is unchanged.
I've checked that interrupts in the i2c controller are still enabled
after writting 0 to the I2C_IRQENABLE_SET register. With this patch
interrupts are disabled in the omap_i2c_runtime_suspend() function.
Patch is based on:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tag: v3.10-rc2
Verified on OMAP4430.
Signed-off-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
On OLPC XO-1.75 (MMP2), a WARN_ON() was occurring during boot
since the clock being enabled by i2c-pxa had not been prepared.
Use clk_prepare_enable() to ensure that the prepare operation
has taken place, and use clk_disable_unprepare() in the matching
shutdown paths.
Signed-off-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This reverts commit c80f52847c.
Regressions have been found and also run time based instantiation would
fail. We need more thoughts on this.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
We have used the default clock associated with the block
for a long time, only heuristics in the clock system has
made this work anyway. This needs to be done away with as
we start probing this driver and its clocks exclusively
from the device tree.
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This utilize the new pinctrl core PM helpers to transition
the driver to "sleep" and "idle" states, cutting away some
boilerplate code.
Cc: Hebbar Gururaja <gururaja.hebbar@ti.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Nomadik I2C was using a local atomic counter to number
the I2C adapters. This does not work on configurations where
you also add, say a GPIO bit-banged adapter to the system.
They will start to conflict about being adapter 0.
There is no reason to use the numbered adapter function, and
the semantic effect on systems with only Nomadik I2C blocks
will be none - instead of increasing the number atomically
in the driver itself, it is done in the I2C core.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The Nomadik I2C block was introduced with the Nomadik STn8815
SoC (the STn8810 incidentally is identical to the one named
i2c-stu300.c). However as developments have only been tested
on the DB8500 family, it was not properly working with the
STn8815 anymore.
Rectify this by adding some vendor variant data in the same
manner as other PrimeCells, and switch code path depending
on version.
Tested on the S8815 Nomadik dongle.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add the compatible string for the Allwinner A10 i2c controller and the
associated register layout.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The Allwinner i2c controller uses the same logic as the Marvell one, but
with slightly different register offsets.
Introduce a structure that will be passed by either the pdata or
associated to the compatible strings, and that holds the various
registers that might be needed.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
These macros make it more comprehensive to access to useful masked and
shifted area of the various registers used.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch adds support for the I2C bus controllers found on Wondermedia
8xxx-series SoCs. Only master-mode is supported.
Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
[wsa: fixed one macro to shift 8 instead of 16]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The designware block is not always properly disabled in the case of
transfer errors. Interrupts from aborted transfers might be handled
after the data structures for the following transfer are initialised but
before the hardware is set up. This can corrupt the data structures to
the point that the system is stuck in an infinite interrupt loop (where
FIFOs are never emptied because dev->msg_read_idx == dev->msgs_num).
This patch cleanly disables the designware-i2c hardware at the end of
every transfer, be it successful or not.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
[wsa: extended the comment]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
TWI transfer interrupts may be lost when system is heavily handling other
interrupts, while current transfer handler depends on each accurate interrupt
and misses some data in this case. Because there are 2 2-byte FIFOs in blackfin
TWI controller, the occurrence of the data loss can be reduced by reading till
the RX FIFO is empty and writing till the TX FIFO is full.
Reported-by: Bob Maris <mail@maris-ee.eu>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This tries to address an issue found when writing an MFD driver
for the Nomadik STw481x PMICs: as the platform is using device
tree exclusively I want to specify the driver matching like
this:
static const struct of_device_id stw481x_match[] = {
{ .compatible = "st,stw4810", },
{ .compatible = "st,stw4811", },
{},
};
static struct i2c_driver stw481x_driver = {
.driver = {
.name = "stw481x",
.of_match_table = stw481x_match,
},
.probe = stw481x_probe,
.remove = stw481x_remove,
};
However that turns out not to be possible: the I2C probe code
is written so that the probe() call is always passed a match
from i2c_match_id() using non-devicetree matches.
This is probably why most devices using device tree for I2C
clients currently will pass no .of_match_table *at all* but
instead just use .id_table from struct i2c_driver to match
the device. As you realize that means that the whole idea with
compatible strings is discarded, and that is why we find strange
device tree I2C device compatible strings like "product" instead
of "vendor,product" as you could expect.
Let's figure out how to fix this before the mess spreads. This
patch will allow probeing devices with only an of_match_table
as per above, and will pass NULL as the second argument to the
probe() function. If the driver wants to deduce secondary info
from the struct of_device_id .data field, it has to call
of_match_device() on its own match table in the probe function
device tree probe path.
If drivers define both an .of_match_table *AND* a i2c_driver
.id_table, the .of_match_table will take precedence, just
as is done in the i2c_device_match() function in i2c-core.c.
I2C devices probed from device tree should subsequently be
fixed to handle the case where of_match_table() is
used (I think none of them do that today), and platforms should
fix their device trees to use compatible strings for I2C devices
instead of setting the name to Linux device driver names as is
done in multiple cases today.
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use the wrapper functions for getting and setting the driver data using
platform_device instead of using dev_{get,set}_drvdata() with &pdev->dev,
so we can directly pass a struct platform_device.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If a process receives signal while it is waiting for I2C transfer to
complete, an error is returned to the caller and the transfer is aborted.
This can cause the driver to fail subsequent transfers. Also according to
commit d295a86eab (i2c: mv64xxx: work around signals causing I2C
transactions to be aborted) I2C drivers aren't supposed to abort
transactions on signals.
To prevent this switch to use wait_for_completion_timeout() instead of
wait_for_completion_interruptible_timeout() in the designware I2C driver.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for handling pinctrl.
So remove devm_pinctrl_get_select_default() from the driver.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for handling pinctrl.
So remove devm_pinctrl_get_select_default() from the driver.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Asking for a multi-part message to be handled by this driver is racy; it
has been observed that the following sequence is possible with this
driver:
- send start
- send address + write
- send data
- send (repeated) start
- send address + write
- send (repeated) start
- send address + read
- unrecoverable bus hang (except by system reset)
The problem is that the interrupt handling sees the next event after the
first repeated start is sent - the IFLG bit is set in the register even
though INTEN is disabled.
Let's fix this by moving all of the message processing into interrupt
context, rather than having it partly in IRQ and partly in process
context. This allows us to move immediately to the next message in the
interrupt handler and get on with the transfer, rather than incuring a
couple of scheduling switches to get the next message.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Move mv64xxx_i2c_prepare_for_io() higher up in the driver to avoid a
future forward declaration for this function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
As this driver does not advertise protocol mangling support
(I2C_FUNC_PROTOCOL_MANGLING is not set), having code to act on
I2C_M_NOSTART is illogical, and in any case isn't supportable on
anything but the first message - which makes no sense. Remove
the I2C_M_NOSTART code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Propagate the error code from request_irq() rather than ignoring it
entirely.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
As we're changing to using devm_* APIs to fix various problems
in this driver, lets also do devm_kzalloc() while we're here too.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This driver forgets to use clk_put(). Rather than adding clk_put(),
lets instead use devm_clk_get() to obtain this clock so that it's
automatically handled on cleanup.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Eliminate reg_base_p and reg_size, mv64xxx_i2c_unmap_regs() and an
unchecked ioremap() return from this driver by using the devm_*
API for requesting and ioremapping resources.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
mv64xxx_i2c_map_regs() already returns an error code, so lets
propagate that to mv64xxx_i2c_probe()'s caller.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Moorestown support is removed from kernel and Medfield is supported by
i2c-designware-pci. But i2c-intel-mid is still in upstream and community
resources are wasted to maintain it.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0. If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.
Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.
To reduce overall code bloat, make the changes described above.
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
This adds device tree support for the ST DDC I2C driver known
as "stu300" in the kernel tree.
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Pull i2c bugfixes from Wolfram Sang:
"These should have been in rc2 but I missed it due to working on devm
longer than expected.
There is one ID addition, since we are touching the driver anyhow.
And the feature bit documentation is one outcome of a debug session
and will make it easier for users to work around problems. The rest
is typical driver bugfixes."
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: suppress lockdep warning on delete_device
i2c: mv64xxx: work around signals causing I2C transactions to be aborted
i2c: i801: Document feature bits in modinfo
i2c: designware: add Intel BayTrail ACPI ID
i2c: designware: always clear interrupts before enabling them
i2c: designware: fix RX FIFO overrun
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Barry Song <Baohua.Song@csr.com>
i2c: suppress lockdep warning on delete_device
Since commit 846f99749a the following lockdep
warning is thrown in case i2c device is removed (via delete_device sysfs
attribute) which contains subdevices (e.g. i2c multiplexer):
=============================================
[ INFO: possible recursive locking detected ]
3.8.7-0-sampleversion-fct #8 Tainted: G O
---------------------------------------------
bash/3743 is trying to acquire lock:
(s_active#110){++++.+}, at: [<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8
but task is already holding lock:
(s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(s_active#110);
lock(s_active#110);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by bash/3743:
#0: (&buffer->mutex){+.+.+.}, at: [<ffffffff802b3c3c>] sysfs_write_file+0x4c/0x208
#1: (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208
#2: (&adap->userspace_clients_lock/1){+.+.+.}, at: [<ffffffff80454a18>] i2c_sysfs_delete_device+0x90/0x238
#3: (&__lockdep_no_validate__){......}, at: [<ffffffff803dcc24>] device_release_driver+0x24/0x48
stack backtrace:
Call Trace:
[<ffffffff80575cc8>] dump_stack+0x8/0x34
[<ffffffff801b50fc>] __lock_acquire+0x161c/0x2110
[<ffffffff801b5c3c>] lock_acquire+0x4c/0x70
[<ffffffff802b60cc>] sysfs_addrm_finish+0x19c/0x1e0
[<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8
[<ffffffff802b7d8c>] sysfs_remove_group+0x64/0x148
[<ffffffff803d990c>] device_remove_attrs+0x9c/0x1a8
[<ffffffff803d9b1c>] device_del+0x104/0x1d8
[<ffffffff803d9c18>] device_unregister+0x28/0x70
[<ffffffff8045505c>] i2c_del_adapter+0x1cc/0x328
[<ffffffff8045802c>] i2c_del_mux_adapter+0x14/0x38
[<ffffffffc025c108>] pca954x_remove+0x90/0xe0 [pca954x]
[<ffffffff804542f8>] i2c_device_remove+0x80/0xe8
[<ffffffff803dca9c>] __device_release_driver+0x74/0xf8
[<ffffffff803dcc2c>] device_release_driver+0x2c/0x48
[<ffffffff803dbc14>] bus_remove_device+0x13c/0x1d8
[<ffffffff803d9b24>] device_del+0x10c/0x1d8
[<ffffffff803d9c18>] device_unregister+0x28/0x70
[<ffffffff80454b08>] i2c_sysfs_delete_device+0x180/0x238
[<ffffffff802b3cd4>] sysfs_write_file+0xe4/0x208
[<ffffffff8023ddc4>] vfs_write+0xbc/0x160
[<ffffffff8023df6c>] SyS_write+0x54/0xd8
[<ffffffff8013d424>] handle_sys64+0x44/0x64
The problem is already known for USB and PCI subsystems. The reason is that
delete_device attribute is defined statically in i2c-core.c and used for all
devices in i2c subsystem.
Discussion of original USB problem:
http://lkml.indiana.edu/hypermail/linux/kernel/1204.3/01160.html
Commit 356c05d58a introduced new macro to suppress
lockdep warnings for this special case and included workaround for USB code.
LKML discussion of the workaround:
http://lkml.indiana.edu/hypermail/linux/kernel/1205.1/03634.html
As i2c case is in principle the same, the same workaround could be used here.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Do not use interruptible waits in an I2C driver; if a process uses
signals (eg, Xorg uses SIGALRM and SIGPIPE) then these signals can
cause the I2C driver to abort a transaction in progress by another
driver, which can cause that driver to fail. I2C drivers are not
expected to abort transactions on signals.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Duplicate the feature bits documentation in modinfo, as not every user
will read the driver's source code or documentation file.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This is the same controller as on Intel Lynxpoint but the ACPI ID is
different (8086F41). Add support for this.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the I2C bus is put to a low power state by an ACPI method it might pull
the SDA line low (as its power is removed). Once the bus is put to full
power state again, the SDA line is pulled back to high. This transition
looks like a STOP condition from the controller point-of-view which sets
STOP detected bit in its status register causing the driver to fail
subsequent transfers.
Fix this by always clearing all interrupts before we start a transfer.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
i2c_dw_xfer_msg() pushes a number of bytes to transmit/receive
to/from the bus into the TX FIFO.
For master-rx transactions, the maximum amount of data that can be
received is calculated depending solely on TX and RX FIFO load.
This is racy - TX FIFO may contain master-rx data yet to be
processed, which will eventually land into the RX FIFO. This
data is not taken into account and the function may request more
data than the controller is actually capable of storing.
This patch ensures the driver takes into account the outstanding
master-rx data in TX FIFO to prevent RX FIFO overrun.
Signed-off-by: Josef Ahmad <josef.ahmad@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
