CN3860 does not interrupt the CPU when the i2c status changes. If
we get a timeout, and see the status has in fact changed, we know we
have this problem, and drop back to polling.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There is a race between the TWSI interrupt and the condition
that is required before proceeding:
Low-level: interrupt flag bit must be set
High-level controller: valid bit must be clear
If the interrupt comes too early and the condition is not met
the wait will time out, and the transfer is aborted leading
to very poor performance.
To avoid this race retry for the condition ~80 µs later.
The retry is avoided on the very first invocation of
wait_event_timeout() (which tests the condition before entering
the wait and is therefore always wrong in this case).
EEPROM reads on 100kHz i2c now measure ~5.2kB/s, about 1/2 what's
achievable, and much better than the worst-case 100 bytes/sec before.
While at it remove the debug print from the low-level wait function.
Signed-off-by: Peter Swain <pswain@cavium.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Zero-length message support (SMBUS QUICK or i2c) never worked with
the Octeon hardware. Disable SMBUS QUICK support and bail out in
case of a zero-length i2c request.
After this change 'i2c-detect -q' will return an error on Octeon but
the previously reported results were wrong anyway.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
cn78xx has a different interrupt architecture, so we have to manage
the interrupts differently.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use High-Level Controller (HLC) when possible. The HLC can read/write
up to 8 bytes and is completely optional. The most important difference
of the HLC is that it only requires one interrupt for a transfer
(up to 8 bytes) where the low-level read/write requires 2 interrupts
plus one interrupt per transferred byte. Since the interrupts are costly
using the HLC improves the performance. Also, the HLC provides improved
error handling.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
[wsa: fixed trivial checkpatch warnings]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add helper function that reads back a value after writing to
make sure the write is finished and use it in octeon_i2c_write_int().
Signed-off-by: Peter Swain <pswain@cavium.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Switch to the i2c bus recovery framework using generic SCL recovery.
If this fails try to reset the hardware. The recovery is triggered
during START on timeout of the interrupt or failure to reach
the START / repeated-START condition.
The START function is moved to xfer and while at it remove the
xfer debug message (i2c core already provides a debug message
for this).
Signed-off-by: Jan Glauber <jglauber@cavium.com>
[wsa: removed one empty line]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Introduce a function that checks for valid status codes depending
on the phase of a transmit or receive. Also add all existing status
codes and improve error handling for various states.
The Octeon TWSI has an "assert acknowledge" bit (TWSI_CTL_AAK) that
is required to be set in master receive mode until the last byte is
requested. The state check needs to consider if this bit was set.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add helper functions for control, data and status register access.
This simplifies the code and makes the purpose of the register
access clearer.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Rename the [read|write]_sw functions to make it clearer they access
the TWSI registers.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
No functional change, just moving the functions upward in
preparation of improving the recovery.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Convert the adapter timeout to 2 ms independently of depending on CONFIG_HZ.
CONFIG_HZ is 100 for MIPS Cavium-Octeon so the timeout value is not changed.
Also set retries to 5 to improve robustness.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If I2C_M_RECV_LEN is set consider the length byte.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Remove resource values from struct i2c_octeon and use
devm_ioremap_resource helper.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cleanup only without functional change.
- removed DRV_VERSION
- defines: use defines instead of plain values,
use BIT_ULL macro, add comments
- rename waitqueue return value to time_left
- sort local variables by length
- fix indentation and whitespace errors
- make function return void if the result is not used
(octeon_i2c_stop, octeon_i2c_set_clock)
- remove debug code from octeon_i2c_stop
- renamed some functions for readability
- update copyright
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Remove point after parameter description and replace kerneldoc
by a comment if it has no additional no value.
Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
'commit 2637e5fd23 ("i2c: octeon: Fix i2c fail problem when a process is
terminated by a signal")' removed the wait_event_interruptible_timeout to
prevent half/mixed i2c messages from being sent/recievd but forgot to
drop the signal handling case in the return handling. This just removes
this dead code. While at it the return variable is adjusted to the type
expected.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I've been debugging the abnormal operation of i2c on octeon. If a process is
terminated by signal in the middle of i2c operation, next i2c read operation
which is done by another process was failed. So i changed to ignore signal in
the middle of i2c operation. After that the problem was not reproduced.
Signed-off-by: Eunbong Song <eunb.song@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There is simply no reason to be manually setting the private driver
data to NULL in the remove/fail to probe cases. This is just extra
cruft code that can be removed.
A few notes:
* Nothing relies on drvdata being set to NULL.
* The __device_release_driver() function eventually calls
dev_set_drvdata(dev, NULL) anyway, so there's no need to do it
twice.
* I verified that there were no cases where xxx_get_drvdata() was
being called in these drivers and checking for / relying on the NULL
return value.
This could be cleaned up kernel-wide but for now just take the baby
step and remove from the i2c subsystem.
Reported-by: Wolfram Sang <wsa@the-dreams.de>
Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
CONFIG_HOTPLUG is going away as an option. As result the __dev*
markings will be going away.
Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio)
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio)
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3)
Acked-by: Barry Song <baohua.song@csr.com> (for sirf)
Reviewed-by: Jean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
There are three parts to this:
1) Remove the definitions of OCTEON_IRQ_TWSI and OCTEON_IRQ_TWSI2.
The interrupts are specified by the device tree and these hard
coded irq numbers block the used of the irq lines by the irq_domain
code.
2) Remove platform device setup code from octeon-platform.c, it is
now unused.
3) Convert i2c-octeon.c to use device tree. Part of this includes
using the devm_* functions instead of the raw counterparts, thus
simplifying error handling. No functionality is changed.
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: linux-mips@linux-mips.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/3939/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Convert the drivers in drivers/i2c/busses/* to use the
module_platform_driver() macro which makes the code smaller and a bit
simpler.
Cc: Ben Dooks <ben-linux@fluff.org>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Manuel Lauss <manuel.lauss@googlemail.com>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Yong Zhang <yong.zhang0@gmail.com>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
It doesn't make sense to set result to -ETIMEDOUT but return 0 (success)
afterwards. Since there's code in octeon_i2c_start() to handle the
error, it should be called.
Signed-off-by: Bernhard Walle <walle@corscience.de>
Acked-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.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>
