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/2008/7/16/78Signed-off-by: NJean 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: NJean 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: NJean 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: NJon Smirl <jonsmirl@gmail.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

i2c_driver.id_table is mandatory now, so we can simplify
i2c_device_probe() a bit.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

i2c_del_driver() can be simplified a bit.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Use list_for_each_entry_safe() in i2c_del_adapter() and i2c_del_driver().
Signed-off-by: NMatthias Kaehlcke <matthias@kaehlcke.net>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

i2c-core doesn't use seq files, so doesn't need to include
<linux/seq_file.h>.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Use class_for_each_device for iteration.
Signed-off-by: NDave Young <hidave.darkstar@gmail.com>
Signed-off-by: NJean 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: NJean 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: NJean 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: NJean 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: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>

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: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NJean 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: NHans Verkuil <hverkuil@xs4all.nl>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

It is no longer required to hold adapter->clist_lock to call
i2c_check_addr.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>

We only need to hold adapter->clist_lock when we touch the client list.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NMike Rapoport <mike@compulab.co.il>
Signed-off-by: NJean 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: NJean 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: NJean Delvare <khali@linux-fr.org>
Acked-by: NDavid 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: NJean Delvare <khali@linux-fr.org>
Acked-by: NDavid 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: NJean 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: NJean 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: NMark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: NJean 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: NJean 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: NJan Engelhardt <jengelh@gmx.de>
Signed-off-by: NAdrian 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

After the i2c-isa removal some code can become static.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NKay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

There are no users of i2c-isa left, so we can finally get rid of it.
Signed-off-by: NJean Delvare <khali@linux-fr.org>