Delay the call to adapter->client_register() until after we are
certain that the client registration is a success. At this point the
client is fully initialized and we no longer hold the adapter->clist
mutex, so this should prevent the deadlocks if the client_register()
callback needs to take that mutex too, as is the case for the bttv
driver.
This fixes bug #7234.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
i2c: Warn on i2c client creation failure
Warn when an i2c client creation fails. If we don't, the user will
never know something wrong happened, as i2c client creation is
typically called through an attach_adapter callback, those return value
we currently ignore for technical reasons.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c-core: Drop useless bitmaskings
The code generated is exactly the same.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i2c: __must_check fixes (core drivers)
Check for error on sysfs file creation.
Check for error on device registration.
Check for error on class device registration.
Greg, I am not familiar with completion, can you please tell me if I
need to take care of it in the error paths (as I did in this patch,
see /* Needed? */ comments), or if it isn't needed?
These patches were tested, including forced errors, so they should work
fine. But of course more testing can't hurt.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes a bug in the handling of 'ignore' module parameters of I2C
client drivers.
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>
The attached patch marks i2c_smbus_write_block_data() and
i2c_smbus_write_i2c_block_data() buffers as const.
Signed-off-by: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Stop holding the core_lists mutex when we don't actually need it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
semaphore to mutex conversion.
the conversion was generated via scripts, and the result was validated
automatically via a script as well.
build tested.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Speed up i2c_smbus_write_block_data and i2c_smbus_read_i2c_block_data
a bit by using memcpy instead of an explicit loop.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The patch below converts a few i2c semaphores to mutexes
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The removal of I2C_DF_NOTIFY left some out of date comments in the
code. Drop them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This prevents i2c drivers from messing up and forgetting to set the
module owner of their driver. It also reduces the size of their drivers
by one line :)
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jean Delvare <khali@linux-fr.org>
We should use the i2c_driver.driver's .name and .owner fields
instead of the i2c_driver's ones.
This patch updates the core of the i2c drivers: it removes .name and
.owner fields from the struct i2c_device and modify various
functions to use struct device fields instead.
Signed-off-by: Laurent Riffard <laurent.riffard@free.fr>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Do not limit the usage count of i2c clients to 1. In other words,
change the client usage count behavior from the old I2C_CLIENT_ALLOW_USE
to the old I2C_CLIENT_ALLOW_MULTIPLE_USE. The rationale is that no
driver actually needs the limiting behavior, and the unlimiting
behavior is slightly easier to implement.
Update the documentation to reflect this change.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make I2C_CLIENT_ALLOW_USE the default for all i2c clients. It doesn't
hurt if the usage count is actually never used for any given driver,
and allows for nice code simplifications in i2c-core.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
No i2c client uses the I2C_CLIENT_ALLOW_MULTIPLE_USE flag, drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Just about every i2c chip driver sets the I2C_DF_NOTIFY flag, so we
can simply make it the default and drop the flag. If any driver really
doesn't want to be notified when i2c adapters are added, that driver
can simply omit to set .attach_adapter. This approach is also more
robust as it prevents accidental NULL pointer dereferences.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Convert everyone who uses platform_bus_type to include
linux/platform_device.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
This is my rewrite of the SMBus PEC support. The original
implementation was known to have bugs (credits go to Hideki Iwamoto
for reporting many of them recently), and was incomplete due to a
conceptual limitation.
The rewrite affects only software PEC. Hardware PEC needs very little
code and is mostly untouched.
Technically, both implementations differ in that the original one
was emulating PEC in software by modifying the contents of an
i2c_smbus_data union (changing the transaction to a different type),
while the new one works one level lower, on i2c_msg structures (working
on message contents). Due to the definition of the i2c_smbus_data union,
not all SMBus transactions could be handled (at least not without
changing the definition of this union, which would break user-space
compatibility), and those which could had to be implemented
individually. At the opposite, adding PEC to an i2c_msg structure
can be done on any SMBus transaction with common code.
Advantages of the new implementation:
* It's about twice as small (from ~136 lines before to ~70 now, only
counting i2c-core, including blank and comment lines). The memory
used by i2c-core is down by ~640 bytes (~3.5%).
* Easier to validate, less tricky code. The code being common to all
transactions by design, the risk that a bug can stay uncovered is
lower.
* All SMBus transactions have PEC support in I2C emulation mode
(providing the non-PEC transaction is also implemented). Transactions
which have no emulation code right now will get PEC support for free
when they finally get implemented.
* Allows for code simplifications in header files and bus drivers
(patch follows).
Drawbacks (I guess there had to be at least one):
* PEC emulation for non-PEC capable non-I2C SMBus masters was dropped.
It was based on SMBus tricks and doesn't quite fit in the new design.
I don't think it's really a problem, as the benefit was certainly
not worth the additional complexity, but it's only fair that I at
least mention it.
Lastly, let's note that the new implementation does slightly affect
compatibility (both in kernel and user-space), but doesn't actually
break it. Some defines will be dropped, but the code can always be
changed in a way that will work with both the old and the new
implementations. It shouldn't be a problem as there doesn't seem to be
many users of SMBus PEC to date anyway.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch updates the .owner field for the i2c core struct xxxx_driver
variables.
Signed-off-by: Laurent Riffard <laurent.riffard@free.fr>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Drop I2C_SMBUS_I2C_BLOCK_MAX, use I2C_SMBUS_BLOCK_MAX instead.
I2C_SMBUS_I2C_BLOCK_MAX has always been defined to the same value as
I2C_SMBUS_BLOCK_MAX, and this will never change: setting it to a lower
value would make no sense, setting it to a higher value would break
i2c_smbus_data compatibility. There is no point in changing
i2c_smbus_data to support larger block transactions in SMBus mode, as
no SMBus hardware supports more than 32 byte blocks. Thus, for larger
transactions, direct I2C transfers are the way to go.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Move the check for SMBUS_QUICK in i2c_probe() after the forced
addresses have been handled. This makes it possible for a driver to
leave the probed address lists empty, only providing forced addresses,
and get i2c_probe to work even if the bus doesn't support SMBUS_QUICK.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/i2c/i2c-core.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
Jean Delvare
Mark M. Hoffman
Krzysztof Halasa
Ingo Molnar
Arjan van de Ven
Russell King
Greg Kroah-Hartman
Laurent Riffard
Russell King
Hideki Iwamoto