linux-toradex.git/drivers/i2c/i2c-core.c, branch v2.6.27-rc4

i2c: Check for address business before creating clients

2008-08-10T20:56:16+00:00

We check for address business in i2c_probe_address(),
i2c_detect_address() and i2c_new_probed_device(), but this isn't
sufficient. Drivers can call i2c_attach_client() and
i2c_new_device() on any address, so we must check the address there
as well.

This fixes bug #11239:
http://bugzilla.kernel.org/show_bug.cgi?id=11239

Signed-off-by: Jean Delvare

i2c: Fix NULL pointer dereference in i2c_new_probed_device

2008-08-10T20:56:15+00:00

Fix a NULL pointer dereference that happened when calling
i2c_new_probed_device on one of the addresses for which we use byte
reads instead of quick write for detection purpose (that is: 0x30-0x37
and 0x50-0x5f).

Signed-off-by: Hans Verkuil 
Signed-off-by: Jean Delvare

Driver Core: add ability for class_for_each_device to start in middle of list

2008-07-22T04:54:47+00:00

This mirrors the functionality that driver_for_each_device has as well.

We add a start variable, and all callers of the function are fixed up at
the same time.

The block layer will be using this new functionality in a follow-on
patch.


Cc: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman

i2c: Clear i2c_adapter.dev on adapter removal

2008-07-16T17:30:05+00:00

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 
Cc: John Stultz 
Cc: Ingo Molnar

i2c: Add detection capability to new-style drivers

2008-07-14T20:38:36+00:00

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
   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

i2c: Call client_unregister for new-style devices too

2008-07-14T20:38:36+00:00

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 
Cc: David Brownell

i2c: Export the i2c_bus_type symbol

2008-07-14T20:38:35+00:00

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 
Signed-off-by: Jean Delvare

i2c: Simplify i2c_device_probe

2008-07-14T20:38:30+00:00

i2c_driver.id_table is mandatory now, so we can simplify
i2c_device_probe() a bit.

Signed-off-by: Jean Delvare

i2c: Simplify i2c_del_driver()

2008-07-14T20:38:26+00:00

i2c_del_driver() can be simplified a bit.

Signed-off-by: Jean Delvare

i2c: Use list_for_each_entry_safe

2008-07-14T20:38:26+00:00

Use list_for_each_entry_safe() in i2c_del_adapter() and i2c_del_driver().

Signed-off-by: Matthias Kaehlcke 
Signed-off-by: Jean Delvare