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2013-04-02i2c: Make return type of i2c_del_adapter() voidLars-Peter Clausen
i2c_del_adapter() is usually called from a drivers remove callback. The Linux device driver model does not allow the remove callback to fail and all resources allocated in the probe callback need to be freed, as well as all resources which have been provided to the rest of the kernel(for example a I2C adapter) need to be revoked. So any function revoking such resources isn't allowed to fail either. i2c_del_adapter() adheres to this requirement and will never fail. But i2c_del_adapter()'s return type is int, which may cause driver authors to think that it can fail. This led to code constructs like: ret = i2c_del_adapter(...); BUG_ON(ret); Since i2c_del_adapter() always returns 0 the BUG_ON is never hit and essentially becomes dead code, which means it can be removed. Making the return type of i2c_del_adapter() void makes it explicit that the function will never fail and should prevent constructs like the above from re-appearing in the kernel code. All callers of i2c_del_adapter() have already been updated in a previous patch to ignore the return value, so the conversion of the return type from int to void can be done without causing any build failures. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02i2c: Remove detach_adapterLars-Peter Clausen
The detach_adapter callback has been deprecated for quite some time and has no user left. Keeping it alive blocks other cleanups, so remove it. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-24i2c: Add bus recovery infrastructureViresh Kumar
Add i2c bus recovery infrastructure to i2c adapters as specified in the i2c protocol Rev. 03 section 3.1.16 titled "Bus clear". http://www.nxp.com/documents/user_manual/UM10204.pdf Sometimes during operation i2c bus hangs and we need to give dummy clocks to slave device to start the transfer again. Now we may have capability in the bus controller to generate these clocks or platform may have gpio pins which can be toggled to generate dummy clocks. This patch supports both. This patch also adds in generic bus recovery routines gpio or scl line based which can be used by bus controller. In addition controller driver may provide its own version of the bus recovery routine. This doesn't support multi-master recovery for now. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [wsa: changed gpio type to int and minor reformatting] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2012-11-23i2c / ACPI: add ACPI enumeration supportMika Westerberg
ACPI 5 introduced I2cSerialBus resource that makes it possible to enumerate and configure the I2C slave devices behind the I2C controller. This patch adds helper functions to support I2C slave enumeration. An ACPI enabled I2C controller driver only needs to call acpi_i2c_register_devices() in order to get its slave devices enumerated, created and bound to the corresponding ACPI handle. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-13UAPI: (Scripted) Disintegrate include/linuxDavid Howells
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
2012-10-05i2c: Correct struct i2c_driver doc about detectionVivien Didelot
s/address_data/address_list/ in addition to c3813d6. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-31Merge branch 'v4l_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull media updates from Mauro Carvalho Chehab: "This is the first part of the media patches for v3.6. This patch series contain: - new DVB frontend: rtl2832 - new video drivers: adv7393 - some unused files got removed - a selection API cleanup between V4L2 and V4L2 subdev API's - a major redesign at v4l-ioctl2, in order to clean it up - several driver fixes and improvements." * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (174 commits) v4l: Export v4l2-common.h in include/linux/Kbuild media: Revert "[media] Terratec Cinergy S2 USB HD Rev.2" [media] media: Use pr_info not homegrown pr_reg macro [media] Terratec Cinergy S2 USB HD Rev.2 [media] v4l: Correct conflicting V4L2 subdev selection API documentation [media] Feature removal: V4L2 selections API target and flag definitions [media] v4l: Unify selection flags documentation [media] v4l: Unify selection flags [media] v4l: Common documentation for selection targets [media] v4l: Unify selection targets across V4L2 and V4L2 subdev interfaces [media] v4l: Remove "_ACTUAL" from subdev selection API target definition names [media] V4L: Remove "_ACTIVE" from the selection target name definitions [media] media: dvb-usb: print mac address via native %pM [media] s5p-tv: Use module_i2c_driver in sii9234_drv.c file [media] media: gpio-ir-recv: add allowed_protos for platform data [media] s5p-jpeg: Use module_platform_driver in jpeg-core.c file [media] saa7134: fix spelling of detach in label [media] cx88-blackbird: replace ioctl by unlocked_ioctl [media] cx88: don't use current_norm [media] cx88: fix a number of v4l2-compliance violations ...
2012-07-24i2c: Add SCCB supportLaurent Pinchart
SCCB is a serial communication bus developed by Omnivision. Its 2-wire mode is very similar to SMBus byte data transactions, but requires the controller to ignore the ACK bit and to insert a stop condition after each message. Add a device SCCB flag and a message stop flag to be passed to controller drivers. [JD: Kill rogue definition in go7007 driver.] Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-06-29[media] i2c: Export an unlocked flavor of i2c_transferJean Delvare
Some drivers (in particular for TV cards) need exclusive access to their I2C buses for specific operations. Export an unlocked flavor of i2c_transfer to give them full control. The unlocked flavor has the following limitations: * Obviously, caller must hold the i2c adapter lock. * No debug messages are logged. We don't want to log messages while holding a rt_mutex. * No check is done on the existence of adap->algo->master_xfer. It is thus the caller's responsibility to ensure that the function is OK to call. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-05-30i2c: Split I2C_M_NOSTART support out of I2C_FUNC_PROTOCOL_MANGLINGMark Brown
Since there are uses for I2C_M_NOSTART which are much more sensible and standard than most of the protocol mangling functionality (the main one being gather writes to devices where something like a register address needs to be inserted before a block of data) create a new I2C_FUNC_NOSTART for this feature and update all the users to use it. Also strengthen the disrecommendation of the protocol mangling while we're at it. In the case of regmap-i2c we remove the requirement for mangling as I2C_M_NOSTART is the only mangling feature which is being used. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-05-12i2c: implement i2c_verify_adapterStephen Warren
This converts a struct device * to a struct i2c_adapter * while verifying that the device really is an I2C adapter. Just like i2c_verify_client. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-03-26i2c: Update the FSF addressJean Delvare
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-01-06Merge branch 'driver-core-next' into Linux 3.2Greg Kroah-Hartman
This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file, and it fixes the build error in the arch/x86/kernel/microcode_core.c file, that the merge did not catch. The microcode_core.c patch was provided by Stephen Rothwell <sfr@canb.auug.org.au> who was invaluable in the merge issues involved with the large sysdev removal process in the driver-core tree. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-23i2c: Delete ANY_I2C_BUSJean Delvare
Last piece of code using ANY_I2C_BUS was deleted almost 2 years ago, so ANY_I2C_BUS can go away as well. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-11-17I2C: Add helper macro for i2c_driver boilerplateLars-Peter Clausen
This patch introduces the module_i2c_driver macro which is a convenience macro for I2C driver modules similar to module_platform_driver. It is intended to be used by drivers which init/exit section does nothing but register/unregister the I2C driver. By using this macro it is possible to eliminate a few lines of boilerplate code per I2C driver. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-31include: replace linux/module.h with "struct module" wherever possiblePaul Gortmaker
The <linux/module.h> pretty much brings in the kitchen sink along with it, so it should be avoided wherever reasonably possible in terms of being included from other commonly used <linux/something.h> files, as it results in a measureable increase on compile times. The worst culprit was probably device.h since it is used everywhere. This file also had an implicit dependency/usage of mutex.h which was masked by module.h, and is also fixed here at the same time. There are over a dozen other headers that simply declare the struct instead of pulling in the whole file, so follow their lead and simply make it a few more. Most of the implicit dependencies on module.h being present by these headers pulling it in have been now weeded out, so we can finally make this change with hopefully minimal breakage. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31include: convert various register fcns to macros to avoid include chainingPaul Gortmaker
The original implementations reference THIS_MODULE in an inline. We could include <linux/export.h>, but it is better to avoid chaining. Fortunately someone else already thought of this, and made a similar inline into a #define in <linux/device.h> for device_schedule_callback(), [see commit 523ded71de0] so follow that precedent here. Also bubble up any __must_check that were used on the prev. wrapper inline functions up one to the real __register functions, to preserve any prev. sanity checks that were used in those instances. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-30i2c: Functions for byte-swapped smbus_write/read_word_dataJonathan Cameron
Reimplemented at least 17 times discounting error mangling cases where it could be used. Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-05-25hwmon: (jc42) Change detection classJean Delvare
While the JC42-compatible chips are temperature sensors, I2C_CLASS_SPD makes more sense because these chips always live on memory modules. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Guenter Roeck <guenter.roeck@ericsson.com>
2011-03-20i2c: Drop i2c_adapter.idJean Delvare
There is no user left of i2c_adapter.id, so we can get rid of it. Finally! :) Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: Deprecate i2c_driver.attach_adapter and .detach_adapterJean Delvare
The last legitimate user of i2c_driver.attach_adapter and .detach_adapter is gone, so we can finally deprecate these callbacks. The last few drivers which still use these will have to be updated to make use of standard I2C device instantiation ways instead. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: Export i2c_for_each_devJean Delvare
Introduce i2c_for_each_dev(), an i2c device iterator with proper locking for use by i2c-dev. This is needed so that we can get rid of the attach_adapter and detach_adapter legacy callback functions. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: Get rid of <linux/i2c-id.h>Jean Delvare
The last remaining ID in <linux/i2c-id.h> is no longer used anywhere, so we can finally get rid of it. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-03-20i2c: make i2c_get_adapter prototype clearerJean Delvare
Rename the parameter of i2c_get_adapter() to "nr", to make it clear we are passing an adapter number and not an adapter ID (which have gone away by now.) Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-01-21driver-core: remove conditionals around devicetree pointersGrant Likely
Having conditional around the of_match_table and the of_node pointers turns out to make driver code use ugly #ifdef blocks. Drop the conditionals and remove the #ifdef blocks from the affected drivers. Also tidy up minor whitespace issues within the same hunks. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-10i2c: Constify i2c_client where possibleJean Delvare
Helper functions for I2C and SMBus transactions don't modify the i2c_client that is passed to them, so it can be marked const. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-11-15i2c: Mark i2c_adapter.id as deprecatedJean Delvare
It's about time to make it clear that i2c_adapter.id is deprecated. Hopefully this will remind the last user to move over to a different strategy. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Jarod Wilson <jarod@redhat.com> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
2010-10-31i2c: Drop unused I2C_CLASS_TV flagsJean Delvare
There are no users left for I2C_CLASS_TV_ANALOG and I2C_CLASS_TV_DIGITAL, so we can get rid of them. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-10-24i2c: Let i2c_parent_is_i2c_adapter return the parent adapterJean Delvare
This makes the calling site's code clearer IMHO. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Michael Lawnick <ml.lawnick@gmx.de>
2010-10-24i2c: Simplify i2c_parent_is_i2c_adapterJean Delvare
Only i2c devices can have their type set to i2c_adapter_type, so testing the bus type is redundant. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Michael Lawnick <ml.lawnick@gmx.de>
2010-08-11i2c: Multiplexed I2C bus core supportMichael Lawnick
Add multiplexed bus core support. I2C multiplexer and switches like pca954x get instantiated as new adapters per port. Signed-off-by: Michael Lawnick <ml.lawnick@gmx.de> Acked-by: Rodolfo Giometti <giometti@linux.it> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-08-11i2c: Use a separate mutex for userspace client listsJean Delvare
Moving userspace-instantiated clients to separate lists wasn't nearly enough to avoid deadlocks in multiplexed bus cases. We also want to have a dedicated mutex to protect each list. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Michael Lawnick <ml.lawnick@gmx.de>
2010-08-11i2c: Move adapter locking helpers to i2c-coreJean Delvare
Uninline i2c adapter locking helper functions, move them to i2c-core, and use them in i2c-core itself. The functions are still exported for external users. This makes future updates to the locking model (which will be needed for multiplexing support) possible and transparent. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Michael Lawnick <ml.lawnick@gmx.de>
2010-08-11V4L/DVB: Use custom I2C probing function mechanismJean Delvare
Now that i2c-core offers the possibility to provide custom probing function for I2C devices, let's make use of it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-11i2c: Add support for custom probe functionJean Delvare
The probe method used by i2c_new_probed_device() may not be suitable for all cases. Let the caller provide its own, optional probe function. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-10i2c.h: fix kernel-doc warningsRandy Dunlap
Fix kernel-doc warnings in linux/i2c.h: Warning(include/linux/i2c.h:176): No description found for parameter 'alert' Warning(include/linux/i2c.h:259): No description found for parameter 'of_node' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-22Merge remote branch 'origin' into secretlab/next-devicetreeGrant Likely
Merging in current state of Linus' tree to deal with merge conflicts and build failures in vio.c after merge. Conflicts: drivers/i2c/busses/i2c-cpm.c drivers/i2c/busses/i2c-mpc.c drivers/net/gianfar.c Also fixed up one line in arch/powerpc/kernel/vio.c to use the correct node pointer. Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-05-04i2c-core: Use per-adapter userspace device listsJean Delvare
Using a single list for all userspace devices leads to a dead lock on multiplexed buses in some circumstances (mux chip instantiated from userspace). This is solved by using a separate list for each bus segment. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Michael Lawnick <ml.lawnick@gmx.de>
2010-04-29i2c/of: Allow device node to be passed via i2c_board_infoGrant Likely
The struct device_node *of_node pointer is moving out of dev->archdata and into the struct device proper. of_i2c.c needs to set the of_node pointer before the device is registered. Since the i2c subsystem doesn't allow 2 stage allocation and registration of i2c devices, the of_node pointer needs to be passed via the i2c_board_info structure so that it is set prior to registration. This patch adds of_node to struct i2c_board_info (conditional on CONFIG_OF), sets of_node in i2c_new_device(), and modifies of_i2c.c to use the new parameter. The calling of dev_archdata_set_node() from of_i2c will be removed in a subsequent patch when of_node is removed from archdata and all users are converted over. Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-03-02i2c: Document the message size limitZhangfei Gao
i2c_master_send & i2c_master_recv do not support more than 64 kb transfer, since msg.len is u16. Signed-off-by: Zhangfei Gao <zgao6@marvell.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-03-02i2c: Add SMBus alert supportJean Delvare
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>
2009-12-14i2c: Get rid of I2C_CLIENT_MODULE_PARMJean Delvare
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>
2009-12-14i2c: Drop I2C_CLIENT_INSMOD_2 to 8Jean Delvare
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>
2009-12-14i2c: Drop I2C_CLIENT_INSMOD_1Jean Delvare
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>
2009-12-14i2c: Get rid of struct i2c_client_address_dataJean Delvare
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>
2009-12-14i2c: Drop the kind parameter from detect callbacksJean Delvare
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>
2009-12-06i2c: Drop probe, ignore and force module parametersJean Delvare
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>
2009-12-06i2c: Prevent priority inversion on top of bus lockMika Kuoppala
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>
2009-11-07i2c: Add an interface to lock/unlock an I2C bus segmentJean Delvare
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>
2009-09-18i2c: Drop unused i2c_driver.id fieldJean Delvare
Nobody is using i2c_driver.id any longer, so we can drop that field. Signed-off-by: Jean Delvare <khali@linux-fr.org>