linux.git/Documentation/i2c, branch v2.6.27

i2c: Documentation: upgrading clients HOWTO

2008-07-28T11:41:02+00:00

Add a document describing how i2c clients on Linux 2.6 can be
moved from the old to the new driver model.

Signed-off-by: Ben Dooks

i2c: Convert the max6875 driver to a new-style i2c driver

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

The new-style max6875 driver implements the optional detect() callback
to cover the use cases of the legacy driver. I'm curious if anyone
really needs this though, so it might be removed in the feature.

Signed-off-by: Jean Delvare

i2c: Convert the pca9539 driver to a new-style i2c driver

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

The new-style pca9539 driver implements the optional detect() callback
to cover the use cases of the legacy driver.

Warning: users will now have to use the force module parameter to get
the driver to attach to their device. That's not a bad thing as these
devices can't be detected anyway.

Note that this doesn't change the fact that this driver is deprecated
in favor of gpio/pca953x.

Signed-off-by: Jean Delvare

i2c: Convert the pcf8575 driver to a new-style i2c driver

2008-07-16T17:30:06+00:00

The new-style pcf8575 driver implements the optional detect() callback
to cover the use cases of the legacy driver.

Warning: users will now have to use the force module parameter to get
the driver to attach to their device. That's not a bad thing as these
devices can't be detected anyway.

Note that this doesn't change the fact that this driver is deprecated
in favor of gpio/pcf857x.

Signed-off-by: Jean Delvare

i2c: Convert the pcf8574 driver to a new-style i2c driver

2008-07-16T17:30:06+00:00

The new-style pcf8574 driver implements the optional detect() callback
to cover the use cases of the legacy driver.

Warning: users will now have to use the force module parameter to get
the driver to attach to their device. That's not a bad thing as these
devices can't be detected anyway.

Note that this doesn't change the fact that this driver is deprecated
in favor of gpio/pcf857x.

Signed-off-by: Jean Delvare

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: Delete unused function i2c_smbus_write_quick

2008-07-14T20:38:23+00:00

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

i2c-core: Return -Errno, not -1

2008-07-14T20:38:23+00:00

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 
Signed-off-by: Jean Delvare

i2c: Document standard fault codes

2008-07-14T20:38:22+00:00

Create Documentation/i2c/fault-codes to help standardize
fault/error code usage in the I2C stack.  It turns out that
returning -1 (-EPERM) for everything was not at all helpful.

Signed-off-by: David Brownell 
Signed-off-by: Jean Delvare

i2c: Remove 3 deprecated bus drivers

2008-07-14T20:38:22+00:00

This patch contains the scheduled removal of i2c-i810, i2c-prosavage
and i2c-savage4.

Signed-off-by: Adrian Bunk 
Signed-off-by: Jean Delvare