So, if somebody wants to re-implement this in the future, we pinpoint to
a problem case.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This reverts commit 3e5f06bed7. As per
bugzilla #200045, this caused a regression. I don't really see a way to
fix it without having the hardware. So, revert the patch and I will fix
the issue I was seeing originally in the i2c-gpio driver itself. I
couldn't find new users of this algorithm since, so there should be no
one depending on the new behaviour.
Reported-by: Sergey Larin <cerg2010cerg2010@mail.ru>
Fixes: 3e5f06bed7 ("i2c: algo-bit: init the bus to a known state")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Tested-by: Sergey Larin <cerg2010cerg2010@mail.ru>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Ensure the bus is free when we register the adapter. Before the SCL/SDA
wires were in an unknown state. It used to work because sending a byte
has a retry mechanism which was triggered if the bus was initially in a
non-free state. But the graceful way to do it is to initialize
correctly.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Support for enforced STOPs will allow us to use SCCB compatible devices.
Based on a preliminary patch by Wolfram Sang.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_bit_quirk_no_clk_stretch is used in i2c-algo-bit.c only, so
declare it as static.
Signed-off-by: Michele Curti <michele.curti@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add I2C_AQ_NO_CLK_STRETCH to drivers/i2c/algos/i2c-algo-bit.c when getscl
is not available.
Signed-off-by: Nicola Corna <nicola@corna.info>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull more i2c updates from Wolfram Sang:
"Mostly bugfixes, small but wanted cleanups, and Paul's init.h removal
applied"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: rcar: fix NACK error code
i2c: update i2c_algorithm documentation
i2c: rcar: use devm_clk_get to ensure clock is properly ref-counted
i2c: rcar: do not print error if device nacks transfer
i2c: rely on driver core when sanitizing devices
i2c: delete non-required instances of include <linux/init.h>
i2c: acorn: is tristate and should use module.h
i2c: piix4: Standardize log messages
i2c: piix4: Use different message for AMD Auxiliary SMBus Controller
i2c: piix4: Add support for AMD ML and CZ SMBus changes
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>
Since there are uses for I2C_M_NOSTART which are much more sensible and
standard than most of the protocol mangling functionality (the main one
being gather writes to devices where something like a register address
needs to be inserted before a block of data) create a new I2C_FUNC_NOSTART
for this feature and update all the users to use it.
Also strengthen the disrecommendation of the protocol mangling while we're
at it.
In the case of regmap-i2c we remove the requirement for mangling as
I2C_M_NOSTART is the only mangling feature which is being used.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Clock stretching is not supposed to last long, so asking to be
rescheduled while waiting for the clock line to be released by a slave
makes little sense. Odds are that the clock line will long have been
released when we run again, so we will have lost time and may even
get an SMBus timeout because of this.
So just busy-wait in that case. This also participates in the effort
to make i2c-algo-bit usable in contexts that can't sleep.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Pull drm main changes from Dave Airlie:
"This is the main drm pull request, I'm probably going to send two more
smaller ones, will explain below.
This contains a patch that is also in the fbdev tree, but it should be
the same patch, it added an API for hot unplugging framebuffer
devices, and I need that API for a new driver.
It also contains some changes to the i2c tree which Jean has acked,
and one change to moorestown platform stuff in x86.
Highlights:
- new drivers: UDL driver for USB displaylink devices, kms only,
should support correct hotplug operations.
- core: i2c speedups + better hotplug support, EDID overriding via
firmware interface - allows user to load a firmware for a broken
monitor/kvm from userspace, it even has documentation for it.
- exynos: new HDMI audio + hdmi 1.4 + virtual output driver
- gma500: code cleanup
- radeon: cleanups, CS optimisations, streamout support and pageflip
fix
- nouveau: NVD9 displayport support + more reclocking work
- i915: re-enabling GMBUS, finish gpu patch (might help hibernation
who knows), missed irq fixes, stencil tiling fixes, interlaced
support, aliasesd PPGTT support for SNB/IVB, swizzling for SNB/IVB,
semaphore fixes
As well as the usual bunch of cleanups and fixes all over the place.
I've got two things I'd like to merge a bit later:
a) AMD support for all their new radeonhd 7000 series GPU and APUs.
AMD dropped this a bit late due to insane internal review
processes, (please AMD just follow Intel and let open source guys
ship stuff early) however I don't want to penalise people who own
this hardware (since its been on sale for 3-4 months and GPU hw
doesn't exactly have a lifetime in years) and consign them to
using closed drivers for longer than necessary. The changes are
well contained and just plug into the driver new gpu functionality
so they should be fairly regression proof. I just want to give
them a bit of a run on the hw AMD kindly sent me.
b) drm prime/dma-buf interface code. This is just infrastructure
code to expose the dma-buf stuff to drm drivers and to userspace.
I'm not planning on pushing any driver support in this cycle
(except maybe exynos), but I'd like to get the infrastructure code
in so for the next cycle I can start getting the driver support
into the individual drivers. We have started driver support for
i915, nouveau and udl along with I think exynos and omap in
staging. However this code relies on the dma-buf tree being
pulled into your tree first since it needs the latest interfaces
from that tree. I'll push to get that tree sent asap.
(oh and any warnings you see in i915 are gcc's fault from what anyone
can see)."
Fix up trivial conflicts in arch/x86/platform/mrst/mrst.c due to the new
msic_thermal_platform_data() thermal function being added next to the
tc35876x_platform_data() i2c device function..
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (326 commits)
drm/i915: use DDC_ADDR instead of hard-coding it
drm/radeon: use DDC_ADDR instead of hard-coding it
drm: remove unneeded redefinition of DDC_ADDR
drm/exynos: added virtual display driver.
drm: allow loading an EDID as firmware to override broken monitor
drm/exynos: enable hdmi audio feature
drm/exynos: add default pixel format for plane
drm/exynos: cleanup exynos_hdmi.h
drm/exynos: add is_local member in exynos_drm_subdrv struct
drm/exynos: add subdrv open/close functions
drm/exynos: remove module of exynos drm subdrv
drm/exynos: release pending pageflip events when closed
drm/exynos: added new funtion to get/put dma address.
drm/exynos: update gem and buffer framework.
drm/exynos: added mode_fixup feature and code clean.
drm/exynos: add HDMI version 1.4 support
drm/exynos: remove exynos_mixer.h
gma500: Fix mmap frambuffer
drm/radeon: Drop radeon_gem_object_(un)pin.
drm/radeon: Restrict offset for legacy display engine.
...
When the system is under heavy load, there can be a significant delay
between the getscl() and time_after() calls inside sclhi(). That delay
may cause the time_after() check to trigger after SCL has gone high,
causing sclhi() to return -ETIMEDOUT.
To fix the problem, double check that SCL is still low after the
timeout has been reached, before deciding to return -ETIMEDOUT.
Signed-off-by: Ville Syrjala <syrjala@sci.fi>
Cc: stable@vger.kernel.org
Signed-off-by: Jean Delvare <khali@linux-fr.org>
i915 has a hw i2c controller (gmbus) but for a bunch of stupid reasons
we need to be able to fall back to the bit-banging algo on gpio pins.
The current code sets up a 2nd i2c controller for the same i2c bus using
the bit-banging algo. This has a bunch of issues, the major one being
that userspace can directly access this fallback i2c adaptor behind
the drivers back.
But we need to frob a few registers before and after using fallback
gpio bit-banging, so this horribly fails.
The new plan is to only set up one i2c adaptor and transparently fall
back to bit-banging by directly calling the xfer function of the bit-
banging algo in the i2c core.
To make that possible, export the 2 i2c algo functions.
v2: As suggested by Jean Delvare, simply export the i2c_bit_algo
vtable instead of the individual functions.
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The wrong bits were put on the wire, fix that.
This fixes kernel bug #42562.
Signed-off-by: Sheng-Hui J. Chu <jeffchu@broadcom.com>
Cc: stable@kernel.org
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Adjust i2c-algo-bit to return fault codes compliant with
Documentation/i2c/fault-codes, rather than the undocumented and
vague -EREMOTEIO.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
If bus testing fails due to the bus being seen as busy, it might be
helpful for developers to know which line is unexpectedly low.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Alex Deucher <alexdeucher@gmail.com>
Always failing to register I2C buses when the line testing fails is a
little harsh. While such a failure is definitely a bug in the driver
that exposes the affected I2C bus, things may still work fine if the
missing initialization steps are done later, before the I2C bus is
used. So it seems a better debugging tool to just report the test
failure by default. I introduce bit_test=2 if anyone really misses the
original behavior of bit_test=1.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Alex Deucher <alexdeucher@gmail.com>
Apparently some distros set i2c-algo-bit.bit_test to 1 by
default. In some cases this causes i2c_bit_add_bus
to fail and prevents the i2c bus from being added. In the
radeon case, we fail to add the ddc i2c buses which prevents
the driver from being able to detect attached monitors.
The i2c bus works fine even if bit_test fails. This is likely
due to gpio switching that is required and handled in the
pre/post_xfer hooks, so call the pre/post_xfer hooks in the
bit test as well.
Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=36221
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@kernel.org [.38 down to .34]
The I2C specification explicitly describes both SDA and SCL as
bidirectional lines. An I2C master with a read-only SCL is thus not
compliant. If a slow slave stretches the clock, errors will happen,
so the bus can't be considered as reliable.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Use a function pointer to decide whether to call i2c_add_adapter or
i2c_add_numbered_adapter. This makes the code more compact than the
current strategy of having the common code in a separate function.
Signed-off-by: Jean Delvare <khali@linux-fr.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>
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>
When fetching DDC using i2c algo bit, we were often seeing timeouts
before getting valid EDID on a retry. The VESA spec states 2ms is the
DDC timeout, so when this translates into 1 jiffie and we are close
to the end of the time period, it could return with a timeout less than
2ms.
Change this code to use time_after instead of time_after_eq.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Setting a default timeout value on a per-algo basis doesn't make any
sense. Move the default value setting to i2c-core. Individual adapter
drivers can specify a different (non-zero) value if they wish.
Also express the timeout value in a way which results in the same
duration regarless of the value of HZ.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Tighten error paths used by various i2c adapters (mostly x86) so
they return real fault/errno codes instead of a "-1" (which is
most often interpreted as "-EPERM"). Build tested, with eyeball
review.
One minor initial goal is to have adapters consistently return
the code "-ENXIO" when addressing a device doesn't get an ACK
response, at least in the probe paths where they are already
good at stifling related logspam.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Update comments and logging on return path for byte writes. NAK is
an error, to be reported or optionally ignored. Timeouts are always
errors. Lost arbitration is not currently handled, so don't even list
it as an option in the error message.
Don't return bogus EFAULT code for inappropriate NAK; EIO is better,
there is no bad userspace address in question.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Fix *LOTS* of whitespace goofs and checkpatch.pl warnings, strangely
parenthesized ternary expressions, and other CodingStyle glitches.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
* Convert files to UTF-8.
* Also correct some people's names
(one example is Eißfeldt, which was found in a source file.
Given that the author used an ß at all in a source file
indicates that the real name has in fact a 'ß' and not an 'ss',
which is commonly used as a substitute for 'ß' when limited to
7bit.)
* Correct town names (Goettingen -> Göttingen)
* Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313)
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
This fixes a bug in the way i2c-algo-bit handles I2C_M_RECV_LEN,
used to implement i2c_smbus_read_block_data(). Previously, in the
absence of PEC (rarely used!) it would NAK the "length" byte:
S addr Rd [A] [length] NA
That prevents the subsequent data bytes from being read:
S addr Rd [A] [length] { A [data] }* NA
The primary fix just reorders two code blocks, so the length used
in the "should I NAK now?" check incorporates the data which it
just read from the slave device.
However, that move also highlighted other fault handling glitches.
This fixes those by abstracting the RX path ack/nak logic, so it
can be used in more than one location. Also, a few CodingStyle
issues were also resolved.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Improve the debugging features of the i2c-algo-bit driver:
* Make it possible to compile the driver without debugging support
at all, making it much smaller.
* Use dev_dbg() for debugging messages where possible, and dev_err()
for error messages.
* Remove redundant debugging messages.
These changes allowed for minor code cleanups, which are included
as well.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The original i2c-algo-bit implementation uses a 33/66 SCL duty cycle
when bits are being written on the bus. While the I2C specification
doesn't forbid it, this prevents us from driving the I2C bus to its
max speed, limiting us to 66 kbps max on standard I2C busses.
Implementing a 50/50 duty cycle instead lets us max out the bandwidth
up to the theoretical max of 100 kbps on standard I2C busses. This is
particularly important when large amounts of data need to be transfered
over the bus, as is the case with some TV adapters when the firmware is
being uploaded.
In fact this change even allows, at least in theory, fast-mode I2C
support at 125, 166 and 250 kbps. There's no way to reach the
theoretical max of 400 kbps with this implementation. But I don't
think we want to put efforts in that direction anyway: software-driven
I2C is very CPU-intensive and bad for latency.
Other timing changes:
* Don't set SDA high explicitly on error, we're going to issue a stop
condition before we leave anyway.
* If an error occurs when sending the slave address, yield the CPU
before retrying, and remove the additional delay after the new start
condition.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add i2c_bit_add_numbered_bus(), which is equivalent to i2c_bit_add_bus
except that it calls i2c_add_numbered_adapter() at the end instead of
i2c_add_adapter().
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Now that i2c-core lets the i2c bus drivers emulate the SMBus block read
and SMBus block process call transaction types, let's implement that in
the popular i2c bit-banging driver. This will also act as a reference
implementation for other bus drivers which want to do the same.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The i2c-algo-bit driver doesn't behave well on read errors: it'll
bail out without even sending a stop condition on the bus, so the bus
will be stuck. So make sure that we always send a stop condition on
the bus before we leave. The best way to make sure is to always send
it at the end of function bit_xfer.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
i2c: Constify i2c_algorithm declarations, part 1
Make struct i2c_algorithm declarations const in all i2c algorithm
drivers.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c-algo-bit: Cleanups
* Uninline long functions (saves around 1 kB or 15%)
* Refactor code in sclhi()
* Drop redundant udelay on repeated start
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c-algo-bit: Discard the mdelay data struct member
The i2c_algo_bit_data structure has an mdelay member, which is not
used by the algorithm code (the code has always been ifdef'd out.)
Let's discard it to save some code and memory.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Content-Disposition: inline; filename=i2c-algo-error-handling-fix.patch
It is possible for i2c_add_adapter() to fail. Several I2C algorithm
drivers ignore that fact. This (compile-tested only) patch fixes them.
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Merge the algorithm id part (16 upper bits) of the i2c adapters ids
into the definition of the adapters ids directly. After that, we don't
need to OR both ids together for each i2c_adapter structure.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There are no more users of i2c_algorithm.id, so we can finally drop
this structure member.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Don't rely on i2c_algorithm.id to alter the i2c adapter's id, use the
I2C_ALGO_* value directly instead, because i2c_algorithm will soon
have no id member no more.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The name member of the i2c_algorithm is never used, although all
drivers conscientiously fill it. We can drop it completely, this
structure doesn't need to have a name.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
