I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.
As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Move strict I2C address validity check to a single function, and
document the reserved I2C addresses there.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Do basic address validity checks when a client is being registered. We
already had checks in place for devices which are being detected, but
not for devices which are simply instantiated.
This is a very basic check. We don't want to do strict checking here
because some devices are known to infringe the I2C address constraints
(e.g. IR receivers at 7-bit address 0x7a while this value is
supposedly reserved for 10-bit addresses.) So we assume the caller
knows what it is doing.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Matthieu Castet <castet.matthieu@free.fr>
Use the same I2C device presence detection code for legacy and new
device detection functions. This is more consistent and makes the code
smaller.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Matthieu Castet <castet.matthieu@free.fr>
Merging in current state of Linus' tree to deal with merge conflicts and
build failures in vio.c after merge.
Conflicts:
drivers/i2c/busses/i2c-cpm.c
drivers/i2c/busses/i2c-mpc.c
drivers/net/gianfar.c
Also fixed up one line in arch/powerpc/kernel/vio.c to use the
correct node pointer.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
.name, .match_table and .owner are duplicated in both of_platform_driver
and device_driver. This patch is a removes the extra copies from struct
of_platform_driver and converts all users to the device_driver members.
This patch is a pretty mechanical change. The usage model doesn't change
and if any drivers have been missed, or if anything has been fixed up
incorrectly, then it will fail with a compile time error, and the fixup
will be trivial. This patch looks big and scary because it touches so
many files, but it should be pretty safe.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
The ACPI subsystem strictly checks for resource conflicts. When there's
a conflict, it outputs a warning message with all the details needed to
properly diagnose the underlying issue. However, the i2c-nforce2 driver
also prints its own message. Not only is the message redundant, it is at
the KERN_ERR level, which overrides some bootsplash screens for no good
reason. This change removes the two lines that print out the error
messages.
Signed-off-by: Chase Douglas <chase.douglas@canonical.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
As warned by checkpatch.pl, <linux/io.h> should be used instead of
<asm/io.h>.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Fix up some coding style issues. i2c-algo-pca.c has been built
successfully after applying this patch and the binary object is
still exactly the same. Other issues found by checkpatch.pl were
voluntarily not fixed, either to keep readability, or because of
false positive errors.
Signed-off-by: Farid Hammane <farid.hammane@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Fix all coding style issues found by checkpatch.pl.
Signed-off-by: Farid Hammane <farid.hammane@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Fix up coding style issues found by the checkpatch.pl tool.
Signed-off-by: Farid Hammane <farid.hammane@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
GPIO driven I2C bus can be used for controlling the PMIC chip. The
example of such configuration is Samsung Aquila board.
This patch moves initialization code to subsys_initcall() to ensure
that the i2c bus is available early so the regulators can be quickly
probed and available for other devices on their probe() call.
Such solution has been proposed by Mark Brown to fix the problem of
the regulators not beeing available on the peripheral device probe():
http://lists.infradead.org/pipermail/linux-arm-kernel/2010-March/011971.html
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The private_data member of struct file is a void *, there is no need
to cast it.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
It is easier to adjust the flags when you know their default value.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Fix all checkpatch warnings. No functional changes are made.
Signed-off-by: Ivo Manca <pinkel@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Only the oldest devices lack some of the features supported by this
driver. List them explicitly, and default to all features enabled for
all other chips, including the ones added through sysfs. This will
make future driver maintenance easier.
In the unlikely event of a not yet supported device not implementing
all the features, one can always use the disable_features module
parameter to prevent the driver from attempting to use them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Seth Heasley <seth.heasley@intel.com>
Let the user disable selected features normally supported by the
device. This makes it possible to work around possible driver or
hardware bugs if the feature in question doesn't work as intended
for whatever reason.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Felix Rubinstein <felixru@gmail.com>
* 'for-linus/i2c-2635' of git://git.fluff.org/bjdooks/linux: (21 commits)
i2c-highlander: remover superflous variable
i2c-ibm-iic: drop NO_IRQ
i2c-cpm: drop NO_IRQ
i2c-mpc: drop NO_IRQ
MAINTAINERS: add i2c tree for embedded platforms
i2c-pxa: only define 'blue_murder'-function if DEBUG is #defined
i2c-pxa: remove unused macro
i2c-nomadik: fix operator precedence warning
i2c-nomadik: release region when removed
OMAP3: I2C: Clean up Errata 1p153 handling
OMAP2/3: I2C: Errata ID i207: Clear wrong RDR interrupt
omap: i2c: add a timeout to the busy waiting
omap: i2c: make errata 1.153 workaround a separate function
i2c-omap: add mpu wake up latency constraint in i2c
omap: i2c: Add i2c support on omap4 platform
i2c-bfin-twi: return completion in interrupt for smbus quick transfers
i2c-bfin-twi: remove redundant retry
i2c-bfin-twi: fix lost interrupts at high speeds
i2c-bfin-twi: add debug output for error status
i2c-bfin-twi: integrate timeout timer with completion interface
...
When cppcheck found this flaw
[./i2c/busses/i2c-highlander.c:284]: (style) Warning - using char variable in bit operation
it was noted that the 'read'-variable could be simply removed as read_write can
only be 0 or 1 anyhow. So, we remove the flaw and simplify the code.
Reported-by: d binderman <dcb314@hotmail.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Drop NO_IRQ as 0 is the preferred way to describe 'no irq'
(http://lkml.org/lkml/2005/11/21/221). This change is safe, as the driver is
only used on powerpc, where NO_IRQ is 0 anyhow.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Drop NO_IRQ as 0 is the preferred way to describe 'no irq'
(http://lkml.org/lkml/2005/11/21/221). This change is safe, as the driver is
only used on powerpc, where NO_IRQ is 0 anyhow.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Jochen Friedrich <jochen@scram.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Drop NO_IRQ as 0 is the preferred way to describe 'no irq'
(http://lkml.org/lkml/2005/11/21/221). This change is safe, as the driver is
only used on powerpc, where NO_IRQ is 0 anyhow.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Ben Dooks <ben-linux@fluff.org>
This talkative function is also called on timeouts. As timeouts can
happen on regular writes to EEPROMs (no error case), this creates false
positives. Giving lots of details is interesting only for developers
anyhow, so just use the function if DEBUG is #defined.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Cc: Roel Kluin <roel.kluin@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Commit
beea494 ([ARM] Remove EEPROM slave emulation from i2c-pxa driver.)
removed all uses of eedbg, so the definition can go, too.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Fix this warning:
i2c-nomadik.c:707: warning: suggest parentheses around operand of '!' or change '&' to '&&' or '!' to '~'
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
So that the module can be loaded again after an unload.
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Clean up existing Errata 1p153 handling to use generic
errata handling mechanism through dev flag.
Signed-off-by: Manjunatha GK <manjugk@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Under certain rare conditions, I2C_STAT[13].RDR bit may be set
and the corresponding interrupt fire, even there is no data in
the receive FIFO, or the I2C data transfer is still ongoing.
These spurious RDR events must be ignored by the software.
This patch handles and ignores RDR spurious interrupts.
The below sequence is required in interrupt handler for
handling this errata:
1. If RDR is set to 1, clear RDR
2. Read I2C status register and check for BusBusy bit. If BusBusy
bit is set, skip remaining steps.
3. If BusBusy bit is not set, perform read operation on I2C status
register.
4. If RDR is set, clear the same. Check RDR again and clear if it sets
RDR bit again.
5. Perform I2C Data Read operation N number of times(where N is value
read from the register BUFSTAT-RXSTAT bit fields).
Note:
This errata is not applicable for omap2420 and omap4.
It is applicable for:
1. omap2430
2. omap34xx(including omap3630).
Signed-off-by: Manjunatha GK <manjugk@ti.com>
Cc: Hema Kalliguddi <hemahk@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: Aaro Koskinen <Aaro.Koskinen@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The errata 1.153 workaround is busy waiting on XUDF bit in interrupt
context, which may lead to kernel hangs. The problem can be reproduced
by running the bus with wrong (too high) speed.
Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This is to avoid insanely long lines and levels of indentation.
Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Cc: Nishant Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
While waiting for completion of the i2c transfer, the
MPU could hit OFF mode and cause several msecs of
delay that made i2c transfers fail more often. The
extra delays and subsequent re-trys cause i2c clocks
to be active more often. This has also an negative
effect on power consumption.
Created a mechanism for passing and using the
constraint setting function in driver code. The used
mpu wake up latency constraints are now set individually
per bus, and they are calculated based on clock rate
and fifo size.
Thanks to Jarkko Nikula, Moiz Sonasath, Paul Walmsley,
and Nishanth Menon for tuning out the details of
this patch.
Updates by Kevin as requested by Tony:
- Remove omap_set_i2c_constraint_func() in favor of conditionally
adding the flag in omap_i2c_add_bus() in order to keep all the OMAP
conditional checking in a single location.
- Update set_mpu_wkup_lat prototypes to match OMAP PM layer so
OMAP PM function can be used directly in pdata.
Cc: Moiz Sonasath <m-sonasath@ti.com>
Cc: Jarkko Nikula <jhnikula@gmail.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@digia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This patch is rebased version of earlier post to add I2C
driver support to OMAP4 platform. On OMAP4, all
I2C register address offsets are changed from OMAP1/2/3 I2C.
In order to not have #ifdef's at various places in code,
as well as to support multi-OMAP build, an array is created
to hold the register addresses with it's offset.
This patch was submitted, reviewed and acked on mailing list
already. For more details refer below link
http://www.mail-archive.com/linux-i2c@vger.kernel.org/msg02281.html
This updated verion has a depedancy on "Add support for 16-bit registers"
posted on linux-omap. Below is the patch-works link for the same
http://patchwork.kernel.org/patch/72295/
Signed-off-by: Syed Rafiuddin <rafiuddin.syed@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Cc: Cory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
A smbus quick transfer has no data after the address byte.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
i2c event of next read/write byte may trigger before current int state
is cleared in the interrupt handler. So, this should be done at the
beginning of interrupt handler to avoid losing new i2c events.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Add some debug() code to decode the error register.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
There isn't much point in managing our own custom timeout timer when the
completion interface already includes support for it. This makes the
resulting code much simpler and robust.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The S3C I2C controller indicates completion of I2C transfers before
the bus has a stop condition on it. In order to ensure that we do not
attempt to start a new transfer before the bus is idle the driver
currently inserts a 1ms delay. This is vastly larger than is generally
required and has a visible effect on performance under load, such as
when bringing up audio CODECs or reading back status information with
non-bulk I2C reads.
Replace the sleep with a spin on the IIC status register for up to 1ms.
This will busy wait but testing on my SMDK6410 system indicates that
the overwhelming majority of transactions complete on the first spin,
with maximum latencies of less than 10 spins so the absolute overhead
of busy waiting should be at worst comprable to msleep(), and the
overall system performance is dramatically improved.
The main risk is poor interaction with multimaster systems where
we may miss the bus going idle before the next transaction. Defend
against this by falling back to the original 1ms delay after 20 spins.
The overall effect in my testing is an approximately 20% improvement
in kernel startup time.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The following structure elements duplicate the information in
'struct device.of_node' and so are being eliminated. This patch
makes all readers of these elements use device.of_node instead.
(struct of_device *)->node
(struct dev_archdata *)->prom_node (sparc)
(struct dev_archdata *)->of_node (powerpc & microblaze)
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
There are three issues with the i2c bus type's power management
callbacks at the moment. First, they don't include any hibernate
callbacks, although they should at least include the .restore()
callback (there's no guarantee that the driver will be present in
memory before loading the image kernel and we must restore the
pre-hibernation state of the device). Second, the "legacy"
callbacks are not going to be invoked by the PM core since the bus
type's pm object is not NULL. Finally, the system sleep PM
(ie. suspend/resume) callbacks don't check if the device has been
already suspended at run time, in which case they should skip
suspending it. Also, it looks like the i2c bus type can use the
generic subsystem-level runtime PM callbacks.
For these reasons, rework the system sleep PM callbacks provided by
the i2c bus type to handle hibernation correctly and to invoke the
"legacy" callbacks for drivers that provide them. In addition to
that make the i2c bus type use the generic subsystem-level runtime
PM callbacks.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Using a single list for all userspace devices leads to a dead lock
on multiplexed buses in some circumstances (mux chip instantiated
from userspace). This is solved by using a separate list for each
bus segment.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Michael Lawnick <ml.lawnick@gmx.de>
Some FSC hardware monitoring chips (Syleus at least) doesn't like
quick writes we typically use to probe for I2C chips. Use a regular
byte read instead for the address they live at (0x73). These are the
only known chips living at this address on PC systems.
For clarity, this fix should not be needed for kernels 2.6.30 and
later, as we started instantiating the hwmon devices explicitly based
on DMI data. Still, this fix is valuable in the following two cases:
* Support for recent FSC chips on older kernels. The DMI-based device
instantiation is more difficult to backport than the device support
itself.
* Case where the DMI-based device instantiation fails, whatever the
reason. We fall back to probing in that case, so it should work.
This fixes kernel bug #15634:
https://bugzilla.kernel.org/show_bug.cgi?id=15634
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable@kernel.org
After discovering that a lot of i2c-drivers leave the pointer to their
clientdata dangling, it was decided to let the core handle this issue.
It is assumed that the core may access the private data after remove()
as there are no guarantees for the lifetime of such pointers anyhow (see
thread starting at http://lkml.org/lkml/2010/3/21/68)
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
