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>
Make PCI device ids constant as we just did for many other i2c bus
drivers already.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Márton Németh <nm127@freemail.hu>
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>
The struct device_node *of_node pointer is moving out of dev->archdata
and into the struct device proper. of_i2c.c needs to set the of_node
pointer before the device is registered. Since the i2c subsystem
doesn't allow 2 stage allocation and registration of i2c devices, the
of_node pointer needs to be passed via the i2c_board_info structure
so that it is set prior to registration.
This patch adds of_node to struct i2c_board_info (conditional on
CONFIG_OF), sets of_node in i2c_new_device(), and modifies of_i2c.c
to use the new parameter. The calling of dev_archdata_set_node()
from of_i2c will be removed in a subsequent patch when of_node is
removed from archdata and all users are converted over.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
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: Dan Carpenter <error27@gmail.com>
Signed-off-by: Ben 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: Kevin Wells <wellsk40@gmail.com>
Signed-off-by: Ben 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: Kevin Wells <wellsk40@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
- Return -ETIMEDOUT on bus busy error
- Fix timeout test "time_after(jiffies, orig_jiffies + HZ / 1000)" :
By default, HZ=100 on arm. This means that this test has no chances to
work and may result in a dead loop. Set timeout to 500ms.
- Don't try to send a new message if we failed to transmit
previous one. This was preventing to recover from error on my system
Signed-off-by: Arnaud Patard <apatard@mandriva.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Update the Kconfig entry for the i2c-sh_mobile driver to
enable build on SH-Mobile ARM platforms
Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add support for a new version of the IIC block
found in the SH-Mobile ARM line of processors.
Prototype patch written by Nishimoto-san.
Tested on sh7377 and sh7372.
Signed-off-by: NISHIMOTO Hiroki <nishimoto.hiroki@renesas.com>
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Break out register access functions in the
i2c-sh_mobile driver. This update should not
change any driver logic.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
*) add a new HID for IBM SMBus CMI devices
*) add methods for IBM SMBus CMI devices
*) hook different HID with different control methods set
*) minor tweaks as suggested by Jean Delvare
Slightly modified by Darrick to use #define'd IBM SMBUS HID from Darrick's ACPI
scan quirk patch.
Signed-off-by: Crane Cai <crane.cai@amd.com>
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Drivers might have to do random things before and/or after I2C
transfers. Add hooks to the i2c-algo-bit implementation to let them do
so.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Alex Deucher <alexdeucher@gmail.com>
Now that directory drivers/i2c/chips is gone, configuration option
I2C_DEBUG_CHIP no longer has any effect, so we can drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Move the last remaining driver from i2c/chips to misc. Good ridance!
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Experience has shown that the block buffer can only be used for SMBus
(not I2C) block transactions, even though the datasheet doesn't
mention this limitation.
Reported-by: Felix Rubinstein <felixru@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Oleg Ryjkov <oryjkov@gmail.com>
Cc: stable@kernel.org
Be less verbose in the absence of real errors. We don't have to report
failed probes to the users, it's only confusing them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Andrey Gusev <ronne@list.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: stable@kernel.org
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (56 commits)
doc: fix typo in comment explaining rb_tree usage
Remove fs/ntfs/ChangeLog
doc: fix console doc typo
doc: cpuset: Update the cpuset flag file
Fix of spelling in arch/sparc/kernel/leon_kernel.c no longer needed
Remove drivers/parport/ChangeLog
Remove drivers/char/ChangeLog
doc: typo - Table 1-2 should refer to "status", not "statm"
tree-wide: fix typos "ass?o[sc]iac?te" -> "associate" in comments
No need to patch AMD-provided drivers/gpu/drm/radeon/atombios.h
devres/irq: Fix devm_irq_match comment
Remove reference to kthread_create_on_cpu
tree-wide: Assorted spelling fixes
tree-wide: fix 'lenght' typo in comments and code
drm/kms: fix spelling in error message
doc: capitalization and other minor fixes in pnp doc
devres: typo fix s/dev/devm/
Remove redundant trailing semicolons from macros
fix typo "definetly" -> "definitely" in comment
tree-wide: s/widht/width/g typo in comments
...
Fix trivial conflict in Documentation/laptops/00-INDEX
A pointer to omap_i2c_probe is passed to the core via
platform_driver_register and so the function must not disappear when the
.init sections are discarded. Otherwise (if also having HOTPLUG=y)
unbinding and binding a device to the driver via sysfs will result in an
oops as does a device being registered late.
An alternative to this patch is using platform_driver_probe instead of
platform_driver_register plus removing the pointer to the probe function
from the struct platform_driver.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Kalle Jokiniemi <ext-kalle.jokiniemi@nokia.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Cc: chandra shekhar <x0044955@ti.com>
Cc: Jason P Marini <jason.marini@gmail.com>
Cc: Syed Mohammed Khasim <x0khasim@ti.com>
Cc: Jarkko Nikula <jarkko.nikula@nokia.com>
Cc: Juha Yrjola <juha.yrjola@solidboot.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'for-linus/i2c' of git://git.fluff.org/bjdooks/linux:
i2c: Add support for Xilinx XPS IIC Bus Interface
i2c: omap: Add support for 16-bit registers
i2c-pnx: fix setting start/stop condition
powerpc: doc/dts-bindings: update doc of FSL I2C bindings
i2c-mpc: add support for the MPC512x processors from Freescale
i2c-mpc: rename "setclock" initialization functions to "setup"
i2c-mpc: use __devinit[data] for initialization functions and data
i2c/imx: don't add probe function to the driver struct
i2c: Add support for Ux500/Nomadik I2C controller
This patch adds support for the Xilinx XPS IIC Bus Interface.
The driver uses the dynamic mode, supporting to put several
I2C messages in the FIFO to reduce the number of interrupts.
It has the same feature as ocores, it can be passed a list
of devices that will be added when the bus is probed.
Signed-off-by: Richard Röjfors <richard.rojfors@pelagicore.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The current i2c-omap driver is set up for 32-bit registers, which
corresponds to most OMAP devices. However, OMAP730/850 based
devices use a 16-bit register size.
This change modifies the driver to perform a runtime CPU type check
to determine the register sizes, and uses a bit shift of either 1
or 2 bits to compute the proper register sizes for all registers.
Signed-off-by: Cory Maccarrone <darkstar6262@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The start/stop condtions are set in different places repetedly in the i2c-pnx
driver. Beside in i2c_pnx_start and i2c_pnx_stop the start/stop bit are also
set during the transfer of a i2c message in the master_xmit/rcv calls. This is
wrong since we can't set the start/stop condition during the transaction of a
single message any way. As a matter of fact, the driver will sometimes set both
the start and the stop bits at one time. This can be easily reproduced by
sending a simple read request like e.g
struct i2c_msg msgs[] = {
{ addr, 0, 1, buf },
{ addr, I2C_M_RD, offset, buf }
};
While processing the first message the i2c_pnx_master_xmit will set both the
start_bit and the stop_bit, which will eventually confuse the slave.
Fixed by remove setting start/stop condition from the transmit routines.
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
As I2C interrupts must be enabled for the MPC512x by the setup function
as well, "fsl,preserve-clocking" is handled in a slighly different way.
Also, the old settings are now reported calling dev_dbg(). For the
MPC512x the clock setup function of the MPC52xx can be re-used.
Furthermore, the Kconfig help has been updated and corrected.
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
To prepare support for the MPC512x processors from Freescale the
"setclock" initialization functions have been renamed to "setup"
because I2C interrupts must be enabled for the MPC512x by this
function as well.
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
"__devinit[data]" has not yet been used for all initialization functions
and data. To avoid truncating lines, the struct "mpc_i2c_match_data" has
been renamed to "mpc_i2c_data", which is even the better name.
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Having a pointer to the probe function is unnecessary when using
platform_driver_probe and yields a section mismatch warning after
removing the white list entry "*driver" for
{ .data$, .data.rel$ } -> { .init.* } mismatches in modpost.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This adds support for ST-Ericsson's I2C block found
in Ux500 and Nomadik 8815 platforms.
Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Andrea Gallo <andrea.gallo@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Reviewed-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
LPC_SCH is selected by GPI_SCH and I2C_ISCH, even when PCI is not
enabled, but LPC_SCH depends on PCI, so make GPI_SCH and I2C_ISCH
also depend on PCI.
Those 2 selects also need to select what LPC_SCH selects,
since kconfig does not follow selects.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Denis Turischev <denis@compulab.co.il>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Convert i2c-isch to platform_device for the lpc mfd core to add it at probe
time.
Signed-off-by: Denis Turischev <denis@compulab.co.il>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Rename for_each_bit to for_each_set_bit in the kernel source tree. To
permit for_each_clear_bit(), should that ever be added.
The patch includes a macro to map the old for_each_bit() onto the new
for_each_set_bit(). This is a (very) temporary thing to ease the migration.
[akpm@linux-foundation.org: add temporary for_each_bit()]
Suggested-by: Alexey Dobriyan <adobriyan@gmail.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Artem Bityutskiy <dedekind@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
i2c_master_send & i2c_master_recv do not support more than 64 kb
transfer, since msg.len is u16.
Signed-off-by: Zhangfei Gao <zgao6@marvell.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Allow I2C drivers to make use of the runtime PM framework by adding
bus implementations of the runtime PM operations. These simply
immediately suspend when the device is idle. The runtime PM framework
provides drivers with off the shelf refcounts for enables and sysfs
control for managing runtime suspend from userspace so is useful even
without meaningful input from the bus.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add support for the SMBus alert mechanism to the i2c-parport-light
driver. The ADM1032 evaluation board at least is properly wired for
this.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Trent Piepho <tpiepho@freescale.com>
Add support for the SMBus alert mechanism to the i2c-parport driver.
The ADM1032 evaluation board at least is properly wired for this.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Trent Piepho <tpiepho@freescale.com>
Having a separate Kconfig option for i2c-smbus makes it possible to
build that support as a module even when i2c-core itself is built-in.
Bus drivers which implement SMBus alert should select this option, so
in most cases this option is hidden and the user doesn't have to care
about it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Trent Piepho <tpiepho@freescale.com>
SMBus alert support. The SMBus alert protocol allows several SMBus
slave devices to share a single interrupt pin on the SMBus master,
while still allowing the master to know which slave triggered the
interrupt.
This is based on preliminary work by David Brownell. The key
difference between David's implementation and mine is that his was
part of i2c-core, while mine is split into a separate, standalone
module named i2c-smbus. The i2c-smbus module is meant to include
support for all SMBus extensions to the I2C protocol in the future.
The benefit of this approach is a zero cost for I2C bus segments which
do not need SMBus alert support. Where David's implementation
increased the size of struct i2c_adapter by 7% (40 bytes on i386),
mine doesn't touch it. Where David's implementation added over 150
lines of code to i2c-core (+10%), mine doesn't touch it. The only
change that touches all the users of the i2c subsystem is a new
callback in struct i2c_driver (common to both implementations.) I seem
to remember Trent was worried about the footprint of David'd
implementation, hopefully mine addresses the issue.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Trent Piepho <tpiepho@freescale.com>
When the i2c-parport adapter is reponsible for powering devices, it
would seem reasonable to give them some time to settle before trying
to access them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The description of the delay parameter is incomplete, it suggests that
there is a direct relation between the delay value and the bus
frequency. In fact, due to additional delays in the i2c bitbanging
code, the i2c clock is always much slower.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Till Harbaum <Till@Harbaum.org>
The id_table field of the struct pci_driver is constant in <linux/pci.h>
so it is worth to make initialization data also constant.
The semantic match that finds this kind of pattern is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
disable decl_init,const_decl_init;
identifier I1, I2, x;
@@
struct I1 {
...
const struct I2 *x;
...
};
@s@
identifier r.I1, y;
identifier r.x, E;
@@
struct I1 y = {
.x = E,
};
@c@
identifier r.I2;
identifier s.E;
@@
const struct I2 E[] = ... ;
@depends on !c@
identifier r.I2;
identifier s.E;
@@
+ const
struct I2 E[] = ...;
// </smpl>
Signed-off-by: Márton Németh <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Since the drivers data now contains the i2c adapter structure, we can
pass around the drivers data between internal functions (which is what
they want) rather than using the i2c adapter structure and having an
additional pointer dereference each time.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
clk_set_rate() is not supposed to be used to turn clocks on and off.
That's what clk_enable/clk_disable is for.
Acked-by: Vitaly Wool <vitalywool@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In particular, several occurances of funny versions of 'success',
'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address',
'beginning', 'desirable', 'separate' and 'necessary' are fixed.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Joe Perches <joe@perches.com>
Cc: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The functionality bit vector is always returned as a little-endian
32-bit number by the device, so it must be byte-swapped to the host
endianness.
On the other hand, the delay value is handled by the USB stack, so no
byte swapping is needed on our side.
This fixes bug #15105:
http://bugzilla.kernel.org/show_bug.cgi?id=15105
Reported-by: Jens Richter <jens@richter-stutensee.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Jens Richter <jens@richter-stutensee.de>
Cc: Till Harbaum <till@harbaum.org>
Cc: stable@kernel.org
accordingly adapt order of release_mem_region and release_mem_region on
remove.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Cc: Richard Zhao <linuxzsc@gmail.com>
Cc: Darius Augulis <augulis.darius@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: linux-i2c@vger.kernel.org
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
After generating the stop bit by changing MSTA from 1 to 0,
the i2c_imx->stopped was immediatly set to 1. The second test
on i2c_imx->stopped then is correct and the controller never
waits if the bus is busy. This patch corrects this.
On mx31moboard, stop bit was not generated on single write transfers.
This was kept unnoticed as other transfers are made afterwards that
help the write recipient to resynchronize.
Thanks to Philippe and Michael for the debugging.
Signed-off-by: Valentin Longchamp <valentin.longchamp@epfl.ch>
Signed-off by: Philippe Rétornaz <philippe.retornaz@epfl.ch>
Reported-by: Michael Bonani <michael.bonani@epfl.ch>
Acked-by; Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
dev_dbg outputs dev_name, which is released with device_unregister. This bug
resulted in output like this:
i2c Xy2�0: adapter [SMBus I801 adapter at 1880] unregistered
The right output would be:
i2c i2c-0: adapter [SMBus I801 adapter at 1880] unregistered
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Unexpected signals can disturb the bus-handling and lock it up. Don't use
interruptible in 'wait_event_*' and 'wake_*' as in commits
dc1972d027 (for cpm),
1ab082d7cb (for mpc),
b7af349b17 (for omap).
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Remove the following sparse warnings (see "make C=1"):
* drivers/i2c/busses/i2c-ali1563.c:91:3: warning: do-while statement
is not a compound statement
* drivers/i2c/busses/i2c-ali1563.c:161:3: warning: do-while statement
is not a compound statement
Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
With `while (timeout++ < MAX_TIMEOUT)' timeout reaches MAX_TIMEOUT + 1
after the loop. This is probably unlikely to produce a problem.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The C99 specification states in section 6.11.5:
The placement of a storage-class specifier other than at the beginning
of the declaration specifiers in a declaration is an obsolescent
feature.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Current OMAP3 I2C driver code does not follow the correct sequence for soft
reset. Due to this, lock up issues are reported during timeout/error cases.
This patch fixes above issue by disabling I2C controller as per OMAP3430 TRM
for soft reset. As per TRM, I2C controller needs to be disabled as a first
step during soft reset.
Here is correct soft reset sequence:
a. Ensure that the module is disabled
(clear the I2Ci.I2C_CON[15] I2C_EN bit to 0).
b. Set the I2Ci.I2C_SYSC[1] SRST bit to 1.
c. Enable the module by setting I2Ci.I2C_CON[15] I2C_EN bit to 1.
d. Check the I2Ci.I2C_SYSS[0] RDONE bit until it is set to 1 to
indicate the software reset is complete.
Tested on Zoom2, Zoom3, 3430SDP and 3630SDP
Signed-off-by: Manjunatha GK <manjugk@ti.com>
Signed-off-by: George, Harith<harith@ti.com>
Acked-by: Varadarajan, Charu Latha<charu@ti.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Commit ef871432... (i2c-omap: OMAP3: PM: (re)init for every transfer
to support off-mode) introduced a change which make the dev->iestate
contents be written to the OMAP_I2C_IE_REG every time omap_i2c_unidle
is called. Previously, the state was only written if it wasn't equal
to zero.
In omap_i2c_probe, omap_i2c_unidle() is called prior to omap_i2c_init(),
in which case dev->iestate has not yet been initialized and will be set
to zero. Having this value written to the registers causes deadlock
while booting.
As such, this change restores the original functionality.
Signed-off-by: Cory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Calculation of the CLKDIV speed setting should be done using base 10 math
rather than base 2. We also avoid exceeding the spec due to integer
truncation and a 50% duty cycle.
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>
Struct dev_pm_ops is not configured in current i2c bus type. i2c drivers
only depends on suspend/resume entries in struct dev_pm_ops are not
informed of PM suspend and resume events by i2c framework.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Struct i2c_client_address_data only contains one field at this point,
which makes its usefulness questionable. Get rid of it and pass simple
address lists around instead.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
The "kind" parameter always has value -1, and nobody is using it any
longer, so we can remove it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
* 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
ACPICA: Update version to 20091112.
ACPICA: Add additional module-level code support
ACPICA: Deploy new create integer interface where appropriate
ACPICA: New internal utility function to create Integer objects
ACPICA: Add repair for predefined methods that must return sorted lists
ACPICA: Fix possible fault if return Package objects contain NULL elements
ACPICA: Add post-order callback to acpi_walk_namespace
ACPICA: Change package length error message to an info message
ACPICA: Reduce severity of predefined repair messages, Warning to Info
ACPICA: Update version to 20091013
ACPICA: Fix possible memory leak for Scope ASL operator
ACPICA: Remove possibility of executing _REG methods twice
ACPICA: Add repair for bad _MAT buffers
ACPICA: Add repair for bad _BIF/_BIX packages
Because of OMAP off-mode, powerdomain can go off when I2C is idle.
Save enough state, and do a re-init for each transfer.
Additional save/restore state added by Jagadeesh Bhaskar Pakaravoor
(SYSC_REG) and Aaro Koskinen (wakeup sources.)
Also, The OMAP3430 TRM states:
"During active mode (I2Ci.I2C_CON[15] I2C_EN bit is set to 1), make no
changes to the I2Ci.I2C_SCLL and I2Ci.I2C_SCLH registers. Changes may
result in unpredictable behavior."
Hence, the I2C_EN bit should be clearer when modifying these
registers. Please note that clearing the entire I2C_CON register to
disable the I2C module is safe, because the I2C_CON register is
re-configured for each transfer.
Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Cc: Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Jon Hunter <jon-hunter@ti.com>
Cc: Hu Tao <taohu@motorola.com>
Cc: Xiaolong Chen <A21785@motorola.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
In the case of no-ACKs, we don't want to see dev_err() messages in the
console, because some utilities like i2c-tools are capable of printing
decorated console output. This patch will ease such situations.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* ABRT_MASTER_DIS: Fix a typo.
* i2c_dw_handle_tx_abort: Return an appropriate error number
depending on abort_source.
* i2c_dw_xfer: Add a missing abort_source initialization.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Suppose TX_ABRT occurs in the middle of processing i2c_msg msgs[], and
a STOP condition has already been generated on the bus. In this case,
subsequent i2c_dw_xfer_msg() might initiate a new and unnecessary I2C
transaction, which we'd have to avoid.
Furthermore, anytime TX_ABRT is set, the contents of tx/rx buffers are
flushed, so we don't have to process RX_FULL and TX_EMPTY.
Disable interrupts, and skip them.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Current error handling procedures are not good in two respects:
* Forgot to mark dev->cmd_complete as "completed" on errors
Once an I2C transaction is initiated, wait_for_completion_
interruptible_timeout() waits for dev->cmd_complete to be completed.
We have to take care of it whenever an error is detected, otherwise
we will have a needless HZ timeout.
* Forgot to disable interrupts
In the previous patch, interrupt mask operations have been changed.
We don't disable interrupts at the end of the interrupt handler any
more, and try to keep RX_FULL (and TX_EMPTY if required) enabled
during the transaction so that we can send longer data than the size
of Tx/Rx FIFO.
If an error is detected, we need to disable interrupts before
quitting current transaction.
We can work around above points using dev->msg_err effectively.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Currently we disable TX_EMPTY interrupt when buf_len is zero, but this
is wrong. (buf_len == 0) means that all transmit data in the current
i2c_msg message has been sent out, but that doesn't necessarily mean
all i2c_msg messages have been processed.
TX_EMPTY interrupt is used as the driving force of DW I2C transactions,
so we need to keep it enabled as long as i2c_msg messages are available.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Currently we process the first i2c_dw_xfer_msg() in i2c_dw_xfer(),
but in this case there is a possibility to be interrupted by certain
interrupts. As described before in this patchset, we need to keep
providing new transmit data within a given time period, otherwise Tx
FIFO underrun takes place and STOP condition will be generated on the
bus, even if we have more bytes to be written.
In order to exclude all such possibilities, change TX_EMPTY interrupt
usage as below:
* DW_IC_INTR_DEFAULT_MASK: Define a default interrupt mask set, and
put TX_EMPTY there.
* i2c_dw_xfer_init: Enable DW_IC_INTR_DEFAULT_MASK prior to initiating
a new I2C transaction. The first TX_EMPTY will be triggered shortly.
With the help of it, we can make the first call to i2c_dw_xfer_msg()
in the interrupt handler.
* i2c_dw_xfer_msg: Fixup intr_mask operation accordingly. Make sure
that TX_EMPTY operations need to be reversed.
* request_irq: Set IRQF_DISABLED so that we could load transmit data
into Tx FIFO without being distracted by other interrupts.
* Remove i2c_dw_xfer_msg() in i2c_dw_xfer().
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
I2c_dw_xfer_msg() also has the same target address inconsistency check,
and furthermore it checks across all i2c_msg messages, while
i2c_dw_read() walks through i2c_msg messages only with_ I2C_M_RD flag.
That is, target address check in i2c_dw_read() is redundant and useless.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Set proper I2C_FUNC_SMBUS_* bits so that the driver could be used with
some utilities requiring SMBus functionalities, such as i2c-tools.
Note that DW I2C core doesn't support I2C_FUNC_SMBUS_QUICK, as it's not
capable of zero-length data transactions.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
As the driver and hardware always process the given data in parallel,
then it would be better to initialize tx_limit, rx_limit and rx_valid
variables just prior to being used.
This will help us to send / receive as much data as possible.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
While we have a local variable "buf_len" for dev->tx_buf_len, we don't
have such local variable for dev->tx_buf pointer. While "buf_len" is
restored at first then updated when we start processing a new i2c_msg
(determined by STATUS_WRITE_IN_PROGRESS flag), ->tx_buf is different.
Such inconsistency makes the code slightly hard to follow.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We have some steps at the top of i2c_dw_xfer_msg() to set up a slave
address and enable DW I2C core. And it's executed only when we don't
have STATUS_WRITE_IN_PROGRESS.
But we need to make sure that STATUS_WRITE_IN_PROGRESS only indicates
that we have a pending i2c_msg to process. In other words, even if
STATUS_WRITE_IN_PROGRESS is not set, that doesn't mean we're at initial
state in the I2C transaction.
Since i2c_dw_xfer_msg() will be invoked again and again during a
transaction, those init steps have a possibility to be re-processed
needlessly. For example, this issue easily takes place when processing
a combined transaction with a certain condition (the number of tx bytes
in the first i2c_msg, equals to the Tx FIFO depth).
Consequently we should not use STATUS_WRITE_IN_PROGRESS to determine
where we're at in an I2C transaction. It would be better to separate
those initialization steps from i2c_dw_xfer_msg().
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Enable RX_FULL interrupt mask by default, and hook it in the interrupt
handler. If requested amount of rx data (defined by IC_RX_TL) is not
available, we don't have to process i2c_dw_read().
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
As a hardware feature, DW I2C core generates a STOP condition whenever
the Tx FIFO becomes empty (strictly speaking, whenever the last byte in
the Tx FIFO is sent out), even if we have more bytes to be written.
In other words, we must never make "Tx FIFO underrun" happen during
a transaction, except for the last byte. For the safety's sake, we'd
make TX_EMPTY interrupt get triggered every time one byte is processed.
The Rx FIFO threshold needs to be set as well.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Symptom:
--------
When we're going to send/receive the longer size of data than the Tx
FIFO length, the I2C transaction will be divided into several separated
transactions, limited by the Tx FIFO length.
Details:
--------
As a hardware feature, DW I2C core generates a STOP condition whenever
the Tx FIFO becomes empty (strictly speaking, whenever the last byte in
the Tx FIFO is sent out), even if we have more bytes to be written.
Then, once a new transmit data is written to the Tx FIFO, DW I2C core
will initiate a new transaction, which leads to another START condition.
This explains how the transaction in question goes, and implies that
current tasklet-based dw_i2c_pump_msg() strategy couldn't meet the
timing constraint required for avoiding Tx FIFO underrun.
To avoid this scenario, we must keep providing new transmit data within
a given time period. In case of Fast-mode + 32-byte Tx FIFO, for
instance, it takes about 22.5[us] to process single byte, and 720[us] in
total.
This patch removes the existing tasklet-based "pump" system, and move
its jobs into the interrupt handler.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
In case a work-in-progress i2c_msg has more bytes to be written, we
need to set STATUS_WRITE_IN_PROGRESS and exit from the msg_write_idx-
searching loop. Otherwise, we will overtake the current msg_write_idx
without waiting for its transmission to be processed.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* Calculate with accurate conditional expressions from DW manuals.
* Round ic_clk by adding 0.5 as it's important at high ic_clk rate.
* Take into account "tHD;STA" issue for _HCNT calculation.
* Take into account "tf" for _LCNT calculation.
* Add "cond" and "offset" fot further correction requirements.
For _HCNT calculation, there's one issue needs to be carefully
considered; DesignWare I2C core doesn't seem to have solid strategy
to meet the tHD;STA timing spec. If you configure _HCNT based on the
tHIGH timing spec, it easily results in violation of the tHD;STA spec.
After many trials, we came to the conclusion that the tHD;STA period
is proportional to (_HCNT + 3). For the safety's sake, this should be
selected by default.
As for _LCNT calculation, DW I2C core has one characteristic behavior;
he starts counting the SCL CNTs for the LOW period of the SCL clock
(tLOW) as soon as it pulls the SCL line. At that time, he doesn't take
into account the fall time of SCL signal (tf), IOW, he starts counting
CNTs without confirming the SCL input voltage has dropped to below VIL.
This characteristics becomes a problem on some platforms where tf is
considerably long, and results in violation of the tLOW timing spec.
To make the driver configurable as much as possible for various cases,
we'd have separated arguments "tf" and "offset", and for safety default
values should be 0.3 us and 0, respectively.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We couldn't know the original intent for this variable, but at this
point it's useless.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We don't have to use "struct i2c_adapter" pointer here.
Let's use a local "struct dw_i2c_dev" pointer, instead.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We don't have to use "struct i2c_adapter" pointer here.
Let's use a local "struct dw_i2c_dev" pointer, instead.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
We're strongly discouraged from using the IC_CLR_INTR register because
it clears all software-clearable interrupts asserted at the moment.
stat = readl(IC_INTR_STAT);
:
: <=== Interrupts asserted during this period will be lost
:
readl(IC_CLR_INTR);
Instead, use the separately-prepared IC_CLR_* registers.
At the same time, this patch adds all remaining interrupt definitions
available in the DesignWare I2C hardware.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This driver looks originally meant for armel machines where readw()/
writew() works perfectly fine with this hardware. But that doens't
work for big-endian systems.
This patch converts all 8/16-bit-aware usages to 32-bit variants.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Add a module parameter to override the functionality bitfield. This
lets the user disable some commands. This can be used to force a chip
driver to take different code paths.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Functions i2c_do_add_adapter() and __attach_adapter() do essentially
the same thing, differing only in how the parameters are passed. Same
for i2c_do_add_adapter() and __detach_adapter(). Introduce wrappers to
normalize the parameters, so that we do not have to duplicate the
code.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
The Intel 82801 is sometimes used on systems with a BMC connected. The
BMC can access the SMBus, resulting in lost arbitration for the 82801.
We should let i2c-core retry transactions for us in this case.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The BKL is held over a kmalloc so cannot protect anything beyond that.
The two calls before the kmalloc have their own locking.
Improve device open function by removing the now unnecessary ret variable
Signed-off-by: Vincent Sanders <vince@simtec.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The kind parameter of i2c_detect_address() always has value -1, so we
can get rid of it.
Next step is to update all i2c detect callback functions to get rid of
this now useless parameter.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The legacy probe and force module parameters are obsolete now, the
same can be achieved using the new_device sysfs interface, which is
both more flexible and cheaper (it is implemented by i2c-core rather
than replicated in every driver module.)
The legacy ignore module parameters can be dropped as well. Ignoring
can be done by instantiating a "dummy" device at the problematic
address.
This is the first step of a huge cleanup to i2c-core's i2c_detect
function, i2c.h's I2C_CLIENT_INSMOD* macros, and all drivers that made
use of them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
