SMBus alert support. The SMBus alert protocol allows several SMBus
slave devices to share a single interrupt pin on the SMBus master,
while still allowing the master to know which slave triggered the
interrupt.
This is based on preliminary work by David Brownell. The key
difference between David's implementation and mine is that his was
part of i2c-core, while mine is split into a separate, standalone
module named i2c-smbus. The i2c-smbus module is meant to include
support for all SMBus extensions to the I2C protocol in the future.
The benefit of this approach is a zero cost for I2C bus segments which
do not need SMBus alert support. Where David's implementation
increased the size of struct i2c_adapter by 7% (40 bytes on i386),
mine doesn't touch it. Where David's implementation added over 150
lines of code to i2c-core (+10%), mine doesn't touch it. The only
change that touches all the users of the i2c subsystem is a new
callback in struct i2c_driver (common to both implementations.) I seem
to remember Trent was worried about the footprint of David'd
implementation, hopefully mine addresses the issue.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Trent Piepho <tpiepho@freescale.com>
There is no user left of I2C_CLIENT_MODULE_PARM, so we can finally
get rid of this ugly macro.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
These macros simply declare an enum, so drivers might as well declare
it themselves. This puts an end to the arbitrary limit of 8 chip types
per i2c driver.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
This macro simply declares an enum, so drivers might as well declare
it themselves.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Struct i2c_client_address_data only contains one field at this point,
which makes its usefulness questionable. Get rid of it and pass simple
address lists around instead.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
The "kind" parameter always has value -1, and nobody is using it any
longer, so we can remove it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
The legacy probe and force module parameters are obsolete now, the
same can be achieved using the new_device sysfs interface, which is
both more flexible and cheaper (it is implemented by i2c-core rather
than replicated in every driver module.)
The legacy ignore module parameters can be dropped as well. Ignoring
can be done by instantiating a "dummy" device at the problematic
address.
This is the first step of a huge cleanup to i2c-core's i2c_detect
function, i2c.h's I2C_CLIENT_INSMOD* macros, and all drivers that made
use of them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Low priority thread holding the i2c bus mutex could block higher
priority threads to access the bus resulting in unacceptable
latencies. Change the mutex type to rt_mutex preventing priority
inversion.
Tested-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@nokia.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Some drivers need to be able to prevent access to an I2C bus segment
for a specific period of time. Add an interface for them to do so
without twiddling with i2c-core internals.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
For video4linux we sometimes need to probe for a single i2c address.
Normally you would do it like this:
static const unsigned short addrs[] = {
addr, I2C_CLIENT_END
};
client = i2c_new_probed_device(adapter, &info, addrs);
This is a bit awkward and I came up with this macro:
#define V4L2_I2C_ADDRS(addr, addrs...) \
((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
This can construct a list of one or more i2c addresses on the fly. But
this is something that really belongs in i2c.h, renamed to I2C_ADDRS.
With this macro we can just do:
client = i2c_new_probed_device(adapter, &info, I2C_ADDRS(addr));
Note that this can also be used to initialize an array:
static const unsigned short addrs[] = I2C_ADDRS(0x2a, 0x2c);
Whether you want to is another matter, but it works. This functionality is
also available in the oldest supported gcc (3.2).
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Surround i2c function declarations with ifdefs, so that they aren't
advertised when i2c-core isn't actually built. That way, drivers using
these functions unconditionally will result in an immediate build
failure, rather than a late linking failure which is harder to figure
out.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Add a sysfs interface to instantiate and delete I2C devices. This is
primarily a replacement of the force_* module parameters implemented
by some i2c drivers. These module parameters were implemented
internally by the I2C_CLIENT_INSMOD* macros, which don't scale well.
This can also be used when developing a driver on a self-soldered
board which doesn't yet have proper I2C device declaration at the
platform level, and presumably for various debugging situations.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
We used to maintain our own per-adapter list of i2c clients, but this
is redundant with what the driver core does, and no longer needed.
Just drop the redundant list.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Legacy i2c drivers are gone, all drivers are new-style now, so there
is no point to check.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
The legacy i2c_probe() function has no users left, get rid of it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
We converted all the legacy i2c drivers so we can finally get rid of
the legacy binding model. Hooray!
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
These methods were useful in the legacy binding model but no longer in
the new (standard) binding model. There are no users left so we can
drop them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Since the first argument to I2C_BOARD_INFO() must be a string constant,
there is no need to parenthesise it, and adding parentheses results in
an invalid initialiser for char[]. gcc obviously accepts this syntax as
an extension, but sparse complains, e.g.:
drivers/net/sfc/boards.c:173:2: warning: array initialized from parenthesized string constant
Therefore, remove the parentheses.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The new i2c binding model makes the client_register and
client_unregister methods of struct i2c_adapter useless, so we can
remove them with the rest of the legacy model.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The unit in which user-space can set the bus timeout value is jiffies
for historical reasons (back when HZ was always 100.) This is however
not good because user-space doesn't know how long a jiffy lasts. The
timeout value should instead be set in a fixed time unit. Given the
original value of HZ, this unit should be 10 ms, for compatibility.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Let the kernel developers know that i2c_attach_client() and
i2c_detach_client() are deprecated and should no longer be used.
Drivers using these should be converted to the standard device
driver binding model (probe and remove methods.)
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Ben Dooks <ben-linux@fluff.org>
There are a number of drivers which set their i2c bus class to
I2C_CLASS_CAM_DIGITAL, however no chip driver actually checks for this
flag, so we might as well drop it now.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
I2C_CLASS_ALL is almost never what bus driver authors really want.
These i2c classes are really only about which devices must be probed,
not what devices can be present. As device drivers get converted to the
new i2c device driver model, only a few device types will keep relying
on probing.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
If present the info->archdata is copied into the dev->archdata.
Some (OpenFirmware) platforms need it.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Fix most checkpatch.pl errors and warnings. This includes replacing
spaces with tabs in many places, adding and removing spaces, and
folding long lines.
Also complete a couple prototypes to make it clearer what the
parameters represent.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
We have no users and no implementers for these transfer types so it
makes little sense to define functionality bits for them.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
i2c_get_clientdata doesn't change the i2c_client it is passed as a
parameter, so it can be constified. Same for i2c_get_adapdata.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Make clear what the class field of i2c_adapter is good for.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Add missing kernel descriptions of struct i2c_driver members.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: David Brownell <david-b@pacbell.net>
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>
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>
Let general purpose I2C/SMBus bus drivers add SPD to their class. Once
this is done, we will be able to tell the eeprom driver to only probe
for SPD EEPROMs and similar on these buses.
Note that I took a conservative approach here, adding I2C_CLASS_SPD to
many drivers that have no idea whether they can host SPD EEPROMs or not.
This is to make sure that the eeprom driver doesn't stop probing buses
where SPD EEPROMs or equivalent live.
So, bus driver maintainers and users should feel free to remove the SPD
class from drivers those buses never have SPD EEPROMs or they don't
want the eeprom driver to bind to them. Likewise, feel free to add the
SPD class to any bus driver I might have missed.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Let framebuffer drivers set their I2C bus class to DDC. Once this is
done, we will be able to tell the eeprom driver to only probe for
EDID EEPROMs on these buses.
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>
i2c.h mentions -1 as a not-issued irq. This false hint was taken by
of_i2c and caused crashes. Don't give any advice as 'no irq' is not
consistent across all architectures yet and it is not needed internally
by the i2c-core.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
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.
Update most new-style i2c drivers to use standard module aliasing
instead of the old driver_name/type driver matching scheme. I've
left the video drivers apart (except for SoC camera drivers) as
they're a bit more diffcult to deal with, they'll have their own
patch later.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jon Smirl <jonsmirl@gmail.com>
Cc: Jochen Friedrich <jochen@scram.de>
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>
Don't require platform code to be #ifdeffed according to whether
I2C is enabled or not ... if it's not enabled, let GCC compile out
all I2C device declarations. (Issue noted on an NSLU2 build that
didn't configure I2C.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
The C99 specification states in section 6.11.5:
The placement of a storage-class specifier other than at the
beginning of the declaration specifiers in a declaration is an
obsolescent feature.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
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>
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>
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>
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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: 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>
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: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* '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>
Kill a sparse warning by un-nesting two container_of() calls.
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
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>
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>
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: 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>
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>
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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: Jean 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: Jean 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: Jean 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean 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: Jiri Kosina <jikos@jikos.cz>
Signed-off-by: Jean 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: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg 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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg 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: Jean Delvare <khali@linux-fr.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg 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: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg 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: David 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: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This prevents i2c drivers from messing up and forgetting to set the
module owner of their driver. It also reduces the size of their drivers
by one line :)
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jean Delvare <khali@linux-fr.org>
We should use the i2c_driver.driver's .name and .owner fields
instead of the i2c_driver's ones.
This patch updates the core of the i2c drivers: it removes .name and
.owner fields from the struct i2c_device and modify various
functions to use struct device fields instead.
Signed-off-by: Laurent Riffard <laurent.riffard@free.fr>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The i2c_get_client function doesn't exist anymore, so we shouldn't
have a definition for it in i2c.h.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Do not limit the usage count of i2c clients to 1. In other words,
change the client usage count behavior from the old I2C_CLIENT_ALLOW_USE
to the old I2C_CLIENT_ALLOW_MULTIPLE_USE. The rationale is that no
driver actually needs the limiting behavior, and the unlimiting
behavior is slightly easier to implement.
Update the documentation to reflect this change.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make I2C_CLIENT_ALLOW_USE the default for all i2c clients. It doesn't
hurt if the usage count is actually never used for any given driver,
and allows for nice code simplifications in i2c-core.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
No i2c client uses the I2C_CLIENT_ALLOW_MULTIPLE_USE flag, drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The flags member of the i2c_driver structure is no more used. Drop it.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Just about every i2c chip driver sets the I2C_DF_NOTIFY flag, so we
can simply make it the default and drop the flag. If any driver really
doesn't want to be notified when i2c adapters are added, that driver
can simply omit to set .attach_adapter. This approach is also more
robust as it prevents accidental NULL pointer dereferences.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The I2C_DF_DUMMY flag is gone since 2.5.70, it's about time to
drop all ifdef'd out references thereto.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I recently picked up my older work to remove unnecessary #includes of
sched.h, starting from a patch by Dave Jones to not include sched.h
from module.h. This reduces the number of indirect includes of sched.h
by ~300. Another ~400 pointless direct includes can be removed after
this disentangling (patch to follow later).
However, quite a few indirect includes need to be fixed up for this.
In order to feed the patches through -mm with as little disturbance as
possible, I've split out the fixes I accumulated up to now (complete for
i386 and x86_64, more archs to follow later) and post them before the real
patch. This way this large part of the patch is kept simple with only
adding #includes, and all hunks are independent of each other. So if any
hunk rejects or gets in the way of other patches, just drop it. My scripts
will pick it up again in the next round.
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The new SMBus PEC implementation doesn't support PEC emulation on
non-PEC non-I2C SMBus masters, so we can drop all related code.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is my rewrite of the SMBus PEC support. The original
implementation was known to have bugs (credits go to Hideki Iwamoto
for reporting many of them recently), and was incomplete due to a
conceptual limitation.
The rewrite affects only software PEC. Hardware PEC needs very little
code and is mostly untouched.
Technically, both implementations differ in that the original one
was emulating PEC in software by modifying the contents of an
i2c_smbus_data union (changing the transaction to a different type),
while the new one works one level lower, on i2c_msg structures (working
on message contents). Due to the definition of the i2c_smbus_data union,
not all SMBus transactions could be handled (at least not without
changing the definition of this union, which would break user-space
compatibility), and those which could had to be implemented
individually. At the opposite, adding PEC to an i2c_msg structure
can be done on any SMBus transaction with common code.
Advantages of the new implementation:
* It's about twice as small (from ~136 lines before to ~70 now, only
counting i2c-core, including blank and comment lines). The memory
used by i2c-core is down by ~640 bytes (~3.5%).
* Easier to validate, less tricky code. The code being common to all
transactions by design, the risk that a bug can stay uncovered is
lower.
* All SMBus transactions have PEC support in I2C emulation mode
(providing the non-PEC transaction is also implemented). Transactions
which have no emulation code right now will get PEC support for free
when they finally get implemented.
* Allows for code simplifications in header files and bus drivers
(patch follows).
Drawbacks (I guess there had to be at least one):
* PEC emulation for non-PEC capable non-I2C SMBus masters was dropped.
It was based on SMBus tricks and doesn't quite fit in the new design.
I don't think it's really a problem, as the benefit was certainly
not worth the additional complexity, but it's only fair that I at
least mention it.
Lastly, let's note that the new implementation does slightly affect
compatibility (both in kernel and user-space), but doesn't actually
break it. Some defines will be dropped, but the code can always be
changed in a way that will work with both the old and the new
implementations. It shouldn't be a problem as there doesn't seem to be
many users of SMBus PEC to date anyway.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Jean Delvare