Clear i2c_adapter.dev on adapter removal. This makes it possible to
re-add the adapter at a later point, which some drivers
(i2c-amd756-s4882, i2c-nforce2-s4985) actually do.
This fixes a bug reported by John Stultz here:
http://lkml.org/lkml/2008/7/15/720
and by Ingo Molar there:
http://lkml.org/lkml/2008/7/16/78
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Add a mechanism to let new-style i2c drivers optionally autodetect
devices they would support on selected buses and ask i2c-core to
instantiate them. This is a replacement for legacy i2c drivers, much
cleaner.
Where drivers had to implement both a legacy i2c_driver and a
new-style i2c_driver so far, this mechanism makes it possible to get
rid of the legacy i2c_driver and implement both enumerated and
detected device support with just one (new-style) i2c_driver.
Here is a quick conversion guide for these drivers, step by step:
* Delete the legacy driver definition, registration and removal.
Delete the attach_adapter and detach_client methods of the legacy
driver.
* Change the prototype of the legacy detect function from
static int foo_detect(struct i2c_adapter *adapter, int address, int kind);
to
static int foo_detect(struct i2c_client *client, int kind,
struct i2c_board_info *info);
* Set the new-style driver detect callback to this new function, and
set its address_data to &addr_data (addr_data is generally provided
by I2C_CLIENT_INSMOD.)
* Add the appropriate class to the new-style driver. This is
typically the class the legacy attach_adapter method was checking
for. Class checking is now mandatory (done by i2c-core.) See
<linux/i2c.h> for the list of available classes.
* Remove the i2c_client allocation and freeing from the detect
function. A pre-allocated client is now handed to you by i2c-core,
and is freed automatically.
* Make the detect function fill the type field of the i2c_board_info
structure it was passed as a parameter, and return 0, on success. If
the detection fails, return -ENODEV.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
We call adapter->client_register for both legacy and new-style i2c
devices, however we only call adapter->client_unregister for legacy
drivers. This doesn't make much sense. Usually, drivers will undo
in client_unregister what they did in client_register, so we should
call neither or both for every given i2c device.
In order to ease the transition from legacy to new-style devices, it
seems preferable to actually call both.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Export the root of the i2c bus so that PowerPC device tree code can
iterate over devices on the i2c bus.
Signed-off-by: Jon Smirl <jonsmirl@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Use list_for_each_entry_safe() in i2c_del_adapter() and i2c_del_driver().
Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Defend the i2c refcount calls against NULL pointers, as is important
(and conventional) for such calls. Note that none of the current
callers of i2c_use_client() use its return value.
[JD: I hate this but apparently all the other subsystems do it so...]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Provide kerneldoc for most of the I2C and SMBus I/O calls. Add a
comment summarizing some fault reporting issues which affect the
ability to provide clean fault reports through I2C master transfer
calls. (Making it hard to precisely specify their return values...)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Function i2c_smbus_write_quick has no users left, so we can delete it.
Also update the list of these helper functions which are gone but
could be added back if needed.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
More updates to the I2C stack's fault reporting: make the core stop
returning "-1" (usually "-EPERM") for all faults. Instead, pass lower
level fault code up the stack, or return some appropriate errno.
This patch happens to touch almost exclusively SMBus calls.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Remove the old driver_name/type scheme for i2c driver matching. Only the
standard aliasing model will be used from now on.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
As the old driver_name/type matching scheme is going away soon, change
the dummy device mechanism to use the new matching scheme.
This has the downside that dummy i2c clients can no longer choose
their name, they'll all appear as "dummy" in sysfs and in log
messages. I don't think it is a problem in practice though, as there
is little reason to use these i2c clients to log messages.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Based on earlier work by Jon Smirl and Jochen Friedrich.
This patch allows new-style i2c chip drivers to have alias names using
the official kernel aliasing system and MODULE_DEVICE_TABLE(). At this
point, the old i2c driver binding scheme (driver_name/type) is still
supported.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jochen Friedrich <jochen@scram.de>
Cc: Jon Smirl <jonsmirl@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
__FUNCTION__ is gcc-specific, use __func__.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Sometimes kernel-doc and xmlto conspire to create output that is invalid
and causes problems. Until I know a real/better solution, change the
source code that causes this.
If anyone has better fixes or can just explain what is happening here,
that would be great.
xmlto: input does not validate (status 1)
mmotm-2008-0314-1449/Documentation/DocBook/kernel-api.xml:71468: parser error : Opening and ending tag mismatch: programlisting line 71464 and para
</para><para>
^
mmotm-2008-0314-1449/Documentation/DocBook/kernel-api.xml:71480: parser error : Opening and ending tag mismatch: para line 71473 and programlisting
</programlisting></informalexample>
^
make[1]: *** [Documentation/DocBook/kernel-api.html] Error 1
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Ensure that client->driver is set to NULL if the probe() returns an
error (this keeps client->driver and client->dev.driver in sync).
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This adds a i2c_new_dummy() primitive to help work with devices
that consume multiple addresses, which include many I2C eeproms
and at least one RTC.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
It is no longer required to hold adapter->clist_lock to call
i2c_check_addr.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
This goes on top of the patch removing most i2c_adapter.clients usage,
updating i2c_attach_client:
- Don't call device_register() while holding clist_lock. This
removes a self-deadlock when on the i2c_driver.probe() path,
for drivers that need to attach new devices (e.g. dummies).
- Remove a redundant address check. The driver model core does
this as a consequence of guaranteeing unique names.
- Move the "device registered" diagnostic so that it never lies;
previously, on error paths it would falsely report success.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The i2c_adapter.clients list of i2c_client nodes duplicates driver
model state. This patch starts removing that list, letting us remove
most existing users of those i2c-core lists.
* The core I2C code now iterates over the driver model's list instead
of the i2c-internal one in some places where it's safe:
- Passing a command/ioctl to each client, a mechanims
used almost exclusively by DVB adapters;
- Device address checking, in both i2c-core and i2c-dev.
* Provide i2c_verify_client() to use with driver model iterators.
* Flag the relevant i2c_adapter and i2c_client fields as deprecated,
to help prevent new users from appearing.
For the moment the list needs to stick around, since some issues show
up when deleting devices created by legacy I2C drivers. (They don't
follow standard driver model rules. Removing those devices can cause
self-deadlocks.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Allow i2c_transfer to be called in contexts where sleeping is not allowed.
It is the reponsability of the caller to ensure that the underlying i2c bus
driver will not sleep either.
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Rename the main mutex in i2c-core from core_lists to core_lock. This
makes more sense now that the redundant lists are gone.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
i2c_driver.list is superfluous, this list duplicates the one
maintained by the driver core. Drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
i2c_adapter.list is superfluous, this list duplicates the one
maintained by the driver core. Drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Use more standard prototypes for i2c_use_client() and
i2c_release_client(). The former now returns a pointer to the client,
and the latter no longer returns anything. This matches what all other
subsystems do.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Don't implement our own reference counting mechanism for i2c clients
when the driver model already has one.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
This patch allows much of the I2C client address data to move from initdata
into text.
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
i2c_check_addr is only used inside i2c-core now, so we can make it
static and stop exporting it. Thanks to David Brownell for noticing.
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 removes:
- An effectively unused hook: i2c_algorithm.algo_control.
- The i2c_control() call, used only by i2c-dev to call that
unused hook or set two barely supported adapter params.
(That param setting moves into i2c-dev.c ... still iffy
due to lack of locking, but no other changes.)
As shown by diffstat, this is a net code shrink. It also reduces the
complexity of the I2C adapter and /dev interfaces.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Clarify use of the I2C_M_* flags by highlighting the fact that
most of them depend on I2C_FUNC_PROTOCOL_MANGLING.
Also provide kerneldoc for i2c_smbus_read_block_data() and also
for "struct i2c_msg".
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
We need to be able to flag I2C devices, such as RTCs, which can issue wake
events (usually through IRQ lines). This adds an i2c_board_info.flags bit,
and uses it to initialize the i2c device node. (And shrinks a few lines
that were overly long.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.
Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'release' of git://lm-sensors.org/kernel/mhoffman/hwmon-2.6: (44 commits)
i2c: Delete the i2c-isa pseudo bus driver
hwmon: refuse to load abituguru driver on non-Abit boards
hwmon: fix Abit Uguru3 driver detection on some motherboards
hwmon/w83627ehf: Be quiet when no chip is found
hwmon/w83627ehf: No need to initialize fan_min
hwmon/w83627ehf: Export the thermal sensor types
hwmon/w83627ehf: Enable VBAT monitoring
hwmon/w83627ehf: Add support for the VID inputs
hwmon/w83627ehf: Fix timing issues
hwmon/w83627ehf: Add error messages for two error cases
hwmon/w83627ehf: Convert to a platform driver
hwmon/w83627ehf: Update the Kconfig entry
make coretemp_device_remove() static
hwmon: Add LM93 support
hwmon: Improve the pwmN_enable documentation
hwmon/smsc47b397: Don't report missing fans as spinning at 82 RPM
hwmon: Add support for newer uGuru's
hwmon/f71805f: Add temperature-tracking fan control mode
hwmon/w83627ehf: Preserve speed reading when changing fan min
hwmon: fix detection of abituguru volt inputs
...
Manual fixup of trivial conflict in MAINTAINERS file
Let the drivers specify how many bytes they want to read with
i2c_smbus_read_i2c_block_data(). So far, the block count was
hard-coded to I2C_SMBUS_BLOCK_MAX (32), which did not make much sense.
Many driver authors complained about this before, and I believe it's
about time to fix it. Right now, authors have to do technically stupid
things, such as individual byte reads or full-fledged I2C messaging,
to work around the problem. We do not want to encourage that.
I even found that some bus drivers (e.g. i2c-amd8111) already
implemented I2C block read the "right" way, that is, they didn't
follow the old, broken standard. The fact that it was never noticed
before just shows how little i2c_smbus_read_i2c_block_data() was used,
which isn't that surprising given how broken its prototype was so far.
There are some obvious compatiblity considerations:
* This changes the i2c_smbus_read_i2c_block_data() prototype. Users
outside the kernel tree will notice at compilation time, and will
have to update their code.
* User-space has access to i2c_smbus_xfer() directly using i2c-dev, so
the changed expectations would affect tools such as i2cdump. In order
to preserve binary compatibility, we give I2C_SMBUS_I2C_BLOCK_DATA
a new numeric value, and define I2C_SMBUS_I2C_BLOCK_BROKEN with the
old numeric value. When i2c-dev receives a transaction with the
old value, it can convert it to the new format on the fly.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Generate I2C kerneldoc; fix various glitches and add "context" sections to
that documentation. Most I2C and SMBus functions still have no kerneldoc.
Let me suggest providing kerneldoc for all the i2c_smbus_*() functions as
a small and mostly self-contained project for anyone so inclined. :)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Prevent legacy drivers from issuing uevents for device creation/removal,
so that userspace can't cause modprobing loops for them. This became a
problem for some legacy PC drivers. I can't easily see it becoming an
issue with I2C legacy drivers, but consistency-in-paranoia seems likely
to be a good thing here. For usable i2c-level driver model uevents, just
switch to a new-style driver.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add back the i2c_smbus_read_block_data helper function, it is needed
by the upcoming lm93 hardware monitoring driver and possibly others.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Make i2c_del_driver a void function, like all other driver removal
functions. It always returned 0 even when errors occured, and nobody
ever actually checked the return value anyway. And we cannot fail
a module removal anyway.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add a new helper function to instantiate an i2c device. It is meant as a
replacement for i2c_new_device() when you don't know for sure at which
address your I2C/SMBus device lives. This happens frequently on TV
adapters for example, you know there is a tuner chip on the bus, but
depending on the exact board model and revision, it can live at different
addresses. So, the new i2c_new_probed_device() function will probe the bus
according to a list of addresses, and as soon as one of these addresses
responds, it will call i2c_new_device() on that one address.
This function will make it possible to port the old i2c drivers to the
new model quickly.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Make i2c-core.c obey Documentation/CodingStyle better by snugging
the EXPORT_SYMBOL declarations next to the relevant definitions.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This adds a call, i2c_add_numbered_adapter(), registering an I2C adapter
with a specific bus number and then creating I2C device nodes for any
pre-declared devices on that bus. It builds on previous patches adding
I2C probe() and remove() support, and that pre-declaration of devices.
This completes the core support for "new style" I2C device drivers.
Those follow the standard driver model for binding devices to drivers
(using probe and remove methods) rather than a legacy model (where the
driver tries to autoconfigure each bus, and registers devices itself).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This provides partial support for new-style I2C driver binding. It builds
on "struct i2c_board_info" declarations that identify I2C devices on a given
board. This is needed on systems with I2C devices that can't be fully probed
and/or autoconfigured, such as many embedded Linux configurations where the
way a given I2C device is wired may affect how it must be used.
There are two models for declaring such devices:
* LATE -- using a public function i2c_new_device(). This lets modules
declare I2C devices found *AFTER* a given I2C adapter becomes available.
For example, a PCI card could create adapters giving access to utility
chips on that card, and this would be used to associate those chips with
those adapters.
* EARLY -- from arch_initcall() level code, using a non-exported function
i2c_register_board_info(). This copies the declarations *BEFORE* such
an i2c_adapter becomes available, arranging that i2c_new_device() will
be called later when i2c-core registers the relevant i2c_adapter.
For example, arch/.../.../board-*.c files would declare the I2C devices
along with their platform data, and I2C devices would behave much like
PNPACPI devices. (That is, both enumerate from board-specific tables.)
To match the exported i2c_new_device(), the previously-private function
i2c_unregister_device() is now exported.
Pending later patches using these new APIs, this is effectively a NOP.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
