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: NFarid Hammane <farid.hammane@gmail.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Fix all coding style issues found by checkpatch.pl.
Signed-off-by: NFarid Hammane <farid.hammane@gmail.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Fix up coding style issues found by the checkpatch.pl tool.
Signed-off-by: NFarid Hammane <farid.hammane@gmail.com>
Signed-off-by: NJean 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: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Acked-by: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

parport_algo_data is a template so it can be marked const.
Signed-off-by: NJean 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: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

It is easier to adjust the flags when you know their default value.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>

Make PCI device ids constant as we just did for many other i2c bus
drivers already.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: Márton Németh <nm127@freemail.hu>

Fix all checkpatch warnings. No functional changes are made.
Signed-off-by: NIvo Manca <pinkel@gmail.com>
Signed-off-by: NJean 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: NJean Delvare <khali@linux-fr.org>
Acked-by: NSeth 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: NJean Delvare <khali@linux-fr.org>
Cc: Felix Rubinstein <felixru@gmail.com>

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: Nd binderman <dcb314@hotmail.com>
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Acked-by: NJean 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: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NSean 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: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NJochen 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: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NGrant 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: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NEric Miao <eric.y.miao@gmail.com>
Cc: Roel Kluin <roel.kluin@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>

Commit

	beea494d ([ARM] Remove EEPROM slave emulation from i2c-pxa driver.)

removed all uses of eedbg, so the definition can go, too.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Roel Kluin <roel.kluin@gmail.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NWolfram 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: NLinus Walleij <linus.walleij@stericsson.com>
Acked-by: NSrinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: NRabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

So that the module can be loaded again after an unload.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Acked-by: NSrinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: NRabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Clean up existing Errata 1p153 handling to use generic
errata handling mechanism through dev flag.
Signed-off-by: NManjunatha GK <manjugk@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen 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: NManjunatha 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: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen 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: NAlexander Shishkin <virtuoso@slind.org>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This is to avoid insanely long lines and levels of indentation.
Signed-off-by: NAlexander Shishkin <virtuoso@slind.org>
Cc: Nishant Menon <nm@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen 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: NKalle Jokiniemi <kalle.jokiniemi@digia.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen 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: NSyed Rafiuddin <rafiuddin.syed@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NKevin Hilman <khilman@deeprootsystems.com>
Reviewed-by: NPaul Walmsley <paul@pwsan.com>
Cc: Cory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

A smbus quick transfer has no data after the address byte.
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBen 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: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Add some debug() code to decode the error register.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBen 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: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBen 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: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

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: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NJean 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: NJean Delvare <khali@linux-fr.org>
Acked-by: NMichael 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=15634Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NHans 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: NWolfram Sang <w.sang@pengutronix.de>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-i2c@vger.kernel.org
To: ben-linux@fluff.org
To: khali@linux-fr.org
Cc: linux-mips@linux-mips.org
Cc: rade.bozic.ext@nsn.com
Patchwork: http://patchwork.linux-mips.org/patch/1037/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

If we don't find the correct rate, we want to end the loop with "i"
pointing to the last element in the array.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Add a stop condition bit flag to the last byte in the transfer.
This will generate an extra clock to handle the stop condition
and prevent devices from staying in an ACK'd state.
Signed-off-by: NKevin Wells <wellsk40@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

Limit maximum divider to 0x3ff to divider computations. On high I2C
parent clock rates, the divider can exceed 0x3ff. This will help
prevent some very odd clock rates.
Signed-off-by: NKevin Wells <wellsk40@gmail.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>