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>

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>

Rename I2C_FUNC_SMBUS_HWPEC_CALC as I2C_FUNC_SMBUS_PEC, and list that
functionality as always available through the software implementation.
Update documentation accordingly (and list similar requirements).

The way it's currently packaged doesn't present the capability in a
useful way.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Move the i2c-dev support into <linux/i2c-dev.h> where it should always
have lived.  Now <linux/i2c.h> no longer holds stuff related to the
optional userspace /dev/i2c-X interface.  Improve the descriptions
for these ioctl requests.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.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>

Add kernel-doc notation in <linux/i2c.h> for:

Warning(linux-2.6.22-git12//include/linux/i2c.h:183): No description found for parameter 'driver'
Warning(linux-2.6.22-git12//include/linux/i2c.h:183): No description found for parameter 'usage_count'
Warning(linux-2.6.22-git12//include/linux/i2c.h:183): No description found for parameter 'list'
Warning(linux-2.6.22-git12//include/linux/i2c.h:183): No description found for parameter 'released'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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>

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: NJean Delvare <khali@linux-fr.org>

Kill a sparse warning by un-nesting two container_of() calls.
Signed-off-by: NMark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NJean 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: NJean Delvare <khali@linux-fr.org>

Move the declaration of i2c-isa-only exported symbols to i2c-isa
itself, that's the best way to ensure nobody will attempt to use them.
Hopefully we'll get rid of the exports themselves soon anyway.
Signed-off-by: NJean 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: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean 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: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

More update for new style driver support:  add a remove() method, and
use it in the relevant code paths.

Again, nothing will use this yet since there's nothing to create devices
feeding this infrastructure.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

One of a series of I2C infrastructure updates to support enumeration using
the standard Linux driver model.

This patch updates probe() and associated hotplug/coldplug support, but
not remove().  Nothing yet _uses_ it to create I2C devices, so those
hotplug/coldplug mechanisms will be the only externally visible change.
This patch will be an overall NOP since the I2C stack doesn't yet create
clients/devices except as part of binding them to legacy drivers.

Some code is moved earlier in the source code, helping group more of the
per-device infrastructure in one place and simplifying handling per-device
attributes.

Terminology being adopted:  "legacy drivers" create devices (i2c_client)
themselves, while "new style" ones follow the driver model (the i2c_client
is handed to the probe routine).  It's an either/or thing; the two models
don't mix, and drivers that try mixing them won't even be registered.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Let the I2C bus drivers emulate the SMBus Block Read and Block Process
Call transactions if they wish. This requires to define a new message
flag, which i2c-core will use to let the underlying I2C bus driver
know that the first received byte will specify the length of the read
message.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Rename dev_to_i2c_adapter() as to_i2c_adapter(), since the previous
syntax was a surprising and needless difference from normal naming
conventions in Linux.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

This shrinks the size of "struct i2c_client" by 40 bytes:

 - Substantially shrinks the string used to identify the chip type
 - The "flags" don't need to be so big
 - Removes some internal padding

It also adds kerneldoc for that struct, explaining how "name" is really a
chip type identifier; it's otherwise potentially confusing.

Because the I2C_NAME_SIZE symbol was abused for both i2c_client.name
and for i2c_adapter.name, this needed to affect i2c_adapter too.  The
adapters which used that symbol now use the more-obviously-correct
idiom of taking the size of that field.

JD: Shorten i2c_adapter.name from 50 to 48 bytes while we're here, to
avoid wasting space in padding.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Kill i2c_adapter_driver as it doesn't make sense and it prevents
further i2c-core cleanups. i2c_adapter devices are virtual devices
(ex-class devices) and as such they don't need a driver.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Kill i2c_adapter.class_dev. Instead, set the class of i2c_adapter.dev
to i2c_adapter_class, so that a symlink will be created for every
i2c_adapter in /sys/class/i2c-adapter.

The same change must be mirrored to i2c-isa as it duplicates some
of the i2c-core functionalities.

User-space tools and libraries might need some adjustments. In
particular, libsensors from lm_sensors 2.10.3 or later is required for
proper discovery of i2c adapter names after this change.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Driver model updates for the I2C core:

 - Add new suspend(), resume(), and shutdown() methods.  Use them in the
   standard driver model style; document them.

 - Minor doc updates to highlight zero-initialized fields in drivers, and
   the driver model accessors for "clientdata".

If any i2c drivers were previously using the old suspend/resume calls
in "struct driver", they were getting warning messages ... and will
now no longer work.  Other than that, this patch changes no behaviors;
and it lets I2C drivers use conventional PM and shutdown support.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Remove extraneous whitespace from various i2c headers and core files,
like space-before-tab and whitespace at end of line.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

This patch adds the 'level' field into the i2c_adapter structure, which is 
used to represent the 'logical' level of nesting for the purposes of 
lockdep. This field is then used in the i2c_transfer() function, to 
acquire the per-adapter bus_lock with correct nesting level.
Signed-off-by: NJiri Kosina <jikos@jikos.cz>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

i2c: Drop unimplemented slave functions

Drop the function declarations for slave mode support of i2c adapters.
This was never implemented, and by the time it is I bet we will want
something different anyway.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

i2c: Let drivers constify i2c_algorithm data

Let drivers constify I2C algorithm method operations tables,
moving them from ".data" to ".rodata".
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fix the value returned by the i2c-powermac's master_xfer method.
It should return the number of messages processed successfully, but
instead returns the number of data bytes in the first (and only)
processed message.

Also explicitly mention the master_xfer convention so that future
implementations get it right directly.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NGreg 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: NKrzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

It was unconditionally including a whole bunch of headers which aren't
user-visible, and also exposing a lot of private internal stuff of its
own. Also fix some legacy character set to UTF-8 while we're at it.
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

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: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>