Commit Graph

232 Commits

Author SHA1 Message Date
David Howells 8a325997d9 i2c: Add message transfer tracepoints for SMBUS [ver #2]
The SMBUS tracepoints can be enabled thusly:

	echo 1 >/sys/kernel/debug/tracing/events/i2c/enable

and will dump messages that can be viewed in /sys/kernel/debug/tracing/trace
that look like:

         ... smbus_read: i2c-0 a=051 f=0000 c=fa BYTE_DATA
         ... smbus_reply: i2c-0 a=051 f=0000 c=fa BYTE_DATA l=1 [39]
         ... smbus_result: i2c-0 a=051 f=0000 c=fa BYTE_DATA rd res=0

formatted as:

	i2c-<adapter-nr>
	a=<addr>
	f=<flags>
	c=<command>
	<protocol-name>
	<rd|wr>
	res=<result>
	l=<data-len>
	[<data-block>]

The adapters to be traced can be selected by something like:

	echo adapter_nr==1 >/sys/kernel/debug/tracing/events/i2c/filter

Note that this shares the same filter and enablement as i2c.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-13 22:15:07 +01:00
David Howells d9a83d62b3 i2c: Add message transfer tracepoints for I2C
Add tracepoints into the I2C message transfer function to retrieve the message
sent or received.  The following config options must be turned on to make use
of the facility:

	CONFIG_FTRACE
	CONFIG_ENABLE_DEFAULT_TRACERS

The I2C tracepoint can be enabled thusly:

	echo 1 >/sys/kernel/debug/tracing/events/i2c/enable

and will dump messages that can be viewed in /sys/kernel/debug/tracing/trace
that look like:

	... i2c_write: i2c-5 #0 a=044 f=0000 l=2 [02-14]
	... i2c_read: i2c-5 #1 a=044 f=0001 l=4
	... i2c_reply: i2c-5 #1 a=044 f=0001 l=4 [33-00-00-00]
	... i2c_result: i2c-5 n=2 ret=2

formatted as:

	i2c-<adapter-nr>
	#<message-array-index>
	a=<addr>
	f=<flags>
	l=<datalen>
	n=<message-array-size>
	ret=<result>
	[<data>]

The operation is done between the i2c_write/i2c_read lines and the i2c_reply
and i2c_result lines so that if the hardware hangs, the trace buffer can be
consulted to determine the problematic operation.

The adapters to be traced can be selected by something like:

	echo adapter_nr==1 >/sys/kernel/debug/tracing/events/i2c/filter

These changes are based on code from Steven Rostedt.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
[wsa: adapted path for 'enable' in the commit msg]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-13 22:12:53 +01:00
Wolfram Sang 0c17617008 i2c: add deprecation warning for class based instantiation
Class based instantiation can cause noticeable delays when booting. This
mechanism is used when it is not possible to describe slaves on I2C
busses. As we do have other mechanisms, most embedded I2C will not need
classes and for embedded it is explicitly not recommended to use them. Add
a deprecation warning for drivers which want to disable class based
instantiation in the near future to gain boot-up time, so users relying
on this technique can switch to something better. They really should.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-03-05 17:16:45 +01:00
Linus Torvalds f7a6ad9fa2 Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull more i2c updates from Wolfram Sang:
 "Mostly bugfixes, small but wanted cleanups, and Paul's init.h removal
  applied"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: rcar: fix NACK error code
  i2c: update i2c_algorithm documentation
  i2c: rcar: use devm_clk_get to ensure clock is properly ref-counted
  i2c: rcar: do not print error if device nacks transfer
  i2c: rely on driver core when sanitizing devices
  i2c: delete non-required instances of include <linux/init.h>
  i2c: acorn: is tristate and should use module.h
  i2c: piix4: Standardize log messages
  i2c: piix4: Use different message for AMD Auxiliary SMBus Controller
  i2c: piix4: Add support for AMD ML and CZ SMBus changes
2014-01-29 19:56:20 -08:00
Linus Torvalds 9076e0cae7 Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
Pull hwmon updates from Jean Delvare:
 "This include it87 driver improvements, and a tree-wide change of my
  e-mail address"

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  Update Jean Delvare's e-mail address
  hwmon: (it87) Print proper names for the IT8771E and IT8772E
  hwmon: (it87) Add support for the ITE IT8603E
2014-01-29 18:56:27 -08:00
Jean Delvare 7c81c60f37 Update Jean Delvare's e-mail address
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2014-01-29 20:40:08 +01:00
Wolfram Sang 72fa818e8a i2c: rely on driver core when sanitizing devices
Commit 0998d06310 (device-core: Ensure drvdata = NULL when no driver
is bound) modified the driver core to always clear .driver and .drvdata
on remove or probe error. No need for the I2C core to do it.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-24 19:52:25 +01:00
Zhang Rui 8c4ff6d009 ACPI: fix module autoloading for ACPI enumerated devices
ACPI enumerated devices has ACPI style _HID and _CID strings,
all of these strings can be used for both driver loading and matching.

Currently, in Platform, I2C and SPI bus, the ACPI style driver matching
is supported by invoking acpi_driver_match_device() in bus .match() callback.
But, the module autoloading is still broken.

For example, there is any ACPI device with _HID "INTABCD" that is
enumerated to platform bus, and we have a driver that can probe it.

The driver exports its module_alias as "acpi:INTABCD" use the following code
static const struct acpi_device_id xxx_acpi_match[] = {
        { "INTABCD", 0 },
        { }
};
MODULE_DEVICE_TABLE(acpi, xxx_acpi_match);

But, unfortunately, the device' modalias is shown as "platform:INTABCD:00",
please refer to modalias_show() and platform_uevent() in
drivers/base/platform.c.
This results in that the driver will not be loaded automatically when the
device node is created, because their modalias do not match.

This also applies to I2C and SPI bus.

With this patch, the device' modalias will be shown as "acpi:INTABCD" as well.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Mark Brown <broonie@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-16 23:13:10 +01:00
Linus Torvalds 82023bb7f7 More ACPI and power management updates for 3.13-rc1
- ACPI-based device hotplug fixes for issues introduced recently and
   a fix for an older error code path bug in the ACPI PCI host bridge
   driver.
 
 - Fix for recently broken OMAP cpufreq build from Viresh Kumar.
 
 - Fix for a recent hibernation regression related to s2disk.
 
 - Fix for a locking-related regression in the ACPI EC driver from
   Puneet Kumar.
 
 - System suspend error code path fix related to runtime PM and
   runtime PM documentation update from Ulf Hansson.
 
 - cpufreq's conservative governor fix from Xiaoguang Chen.
 
 - New processor IDs for intel_idle and turbostat and removal of
   an obsolete Kconfig option from Len Brown.
 
 - New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and
   ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg.
 
 - Removal of several ACPI video DMI blacklist entries that are not
   necessary any more from Aaron Lu.
 
 - Rework of the ACPI companion representation in struct device and
   code cleanup related to that change from Rafael J Wysocki,
   Lan Tianyu and Jarkko Nikula.
 
 - Fixes for assigning names to ACPI-enumerated I2C and SPI devices
   from Jarkko Nikula.
 
 /
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Merge tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more ACPI and power management updates from Rafael Wysocki:

 - ACPI-based device hotplug fixes for issues introduced recently and a
   fix for an older error code path bug in the ACPI PCI host bridge
   driver

 - Fix for recently broken OMAP cpufreq build from Viresh Kumar

 - Fix for a recent hibernation regression related to s2disk

 - Fix for a locking-related regression in the ACPI EC driver from
   Puneet Kumar

 - System suspend error code path fix related to runtime PM and runtime
   PM documentation update from Ulf Hansson

 - cpufreq's conservative governor fix from Xiaoguang Chen

 - New processor IDs for intel_idle and turbostat and removal of an
   obsolete Kconfig option from Len Brown

 - New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and
   ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg

 - Removal of several ACPI video DMI blacklist entries that are not
   necessary any more from Aaron Lu

 - Rework of the ACPI companion representation in struct device and code
   cleanup related to that change from Rafael J Wysocki, Lan Tianyu and
   Jarkko Nikula

 - Fixes for assigning names to ACPI-enumerated I2C and SPI devices from
   Jarkko Nikula

* tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (24 commits)
  PCI / hotplug / ACPI: Drop unused acpiphp_debug declaration
  ACPI / scan: Set flags.match_driver in acpi_bus_scan_fixed()
  ACPI / PCI root: Clear driver_data before failing enumeration
  ACPI / hotplug: Fix PCI host bridge hot removal
  ACPI / hotplug: Fix acpi_bus_get_device() return value check
  cpufreq: governor: Remove fossil comment in the cpufreq_governor_dbs()
  ACPI / video: clean up DMI table for initial black screen problem
  ACPI / EC: Ensure lock is acquired before accessing ec struct members
  PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()
  ACPI / AC: Remove struct acpi_device pointer from struct acpi_ac
  spi: Use stable dev_name for ACPI enumerated SPI slaves
  i2c: Use stable dev_name for ACPI enumerated I2C slaves
  ACPI: Provide acpi_dev_name accessor for struct acpi_device device name
  ACPI / bind: Use (put|get)_device() on ACPI device objects too
  ACPI: Eliminate the DEVICE_ACPI_HANDLE() macro
  ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
  cpufreq: OMAP: Fix compilation error 'r & ret undeclared'
  PM / Runtime: Fix error path for prepare
  PM / Runtime: Update documentation around probe|remove|suspend
  cpufreq: conservative: set requested_freq to policy max when it is over policy max
  ...
2013-11-20 13:25:04 -08:00
Linus Torvalds 13509c3a9d Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c changes from Wolfram Sang:
 - new drivers for exynos5, bcm kona, and st micro
 - bigger overhauls for drivers mxs and rcar
 - typical driver bugfixes, cleanups, improvements
 - got rid of the superfluous 'driver' member in i2c_client struct This
   touches a few drivers in other subsystems.  All acked.

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits)
  i2c: bcm-kona: fix error return code in bcm_kona_i2c_probe()
  i2c: i2c-eg20t: do not print error message in syslog if no ACK received
  i2c: bcm-kona: Introduce Broadcom I2C Driver
  i2c: cbus-gpio: Fix device tree binding
  i2c: wmt: add missing clk_disable_unprepare() on error
  i2c: designware: add new ACPI IDs
  i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH
  i2c: exynos5: Remove incorrect clk_disable_unprepare
  i2c: i2c-st: Add ST I2C controller
  i2c: exynos5: add High Speed I2C controller driver
  i2c: rcar: fixup rcar type naming
  i2c: scmi: remove some bogus NULL checks
  i2c: sh_mobile & rcar: Enable the driver on all ARM platforms
  i2c: sh_mobile: Convert to clk_prepare/unprepare
  i2c: mux: gpio: use reg value for i2c_add_mux_adapter
  i2c: mux: gpio: use gpio_set_value_cansleep()
  i2c: Include linux/of.h header
  i2c: mxs: Fix PIO mode on i.MX23
  i2c: mxs: Rework the PIO mode operation
  i2c: mxs: distinguish i.MX23 and i.MX28 based I2C controller
  ...
2013-11-18 15:50:07 -08:00
Jarkko Nikula 70762abb9f i2c: Use stable dev_name for ACPI enumerated I2C slaves
Current I2C adapter id - client address "x-00yy" based device naming scheme
is not always stable enough to be used in name based matching, for instance
within ALSA SoC subsystem.

This is problematic in PC kind of platforms where I2C adapter numbers can
change due variable amount of bus controllers, probe order, add-on cards or
just because of BIOS settings.

This patch addresses the problem by using the ACPI device name with
"i2c-" prefix for ACPI enumerated I2C slaves. For them device name
"x-00yz" becomes "i2c-INTABCD:ij" after this patch.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-14 23:20:45 +01:00
Rafael J. Wysocki 7b1998116b ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
Modify struct acpi_dev_node to contain a pointer to struct acpi_device
associated with the given device object (that is, its ACPI companion
device) instead of an ACPI handle corresponding to it.  Introduce two
new macros for manipulating that pointer in a CONFIG_ACPI-safe way,
ACPI_COMPANION() and ACPI_COMPANION_SET(), and rework the
ACPI_HANDLE() macro to take the above changes into account.
Drop the ACPI_HANDLE_SET() macro entirely and rework its users to
use ACPI_COMPANION_SET() instead.  For some of them who used to
pass the result of acpi_get_child() directly to ACPI_HANDLE_SET()
introduce a helper routine acpi_preset_companion() doing an
equivalent thing.

The main motivation for doing this is that there are things
represented by struct acpi_device objects that don't have valid
ACPI handles (so called fixed ACPI hardware features, such as
power and sleep buttons) and we would like to create platform
device objects for them and "glue" them to their ACPI companions
in the usual way (which currently is impossible due to the
lack of valid ACPI handles).  However, there are more reasons
why it may be useful.

First, struct acpi_device pointers allow of much better type checking
than void pointers which are ACPI handles, so it should be more
difficult to write buggy code using modified struct acpi_dev_node
and the new macros.  Second, the change should help to reduce (over
time) the number of places in which the result of ACPI_HANDLE() is
passed to acpi_bus_get_device() in order to obtain a pointer to the
struct acpi_device associated with the given "physical" device,
because now that pointer is returned by ACPI_COMPANION() directly.
Finally, the change should make it easier to write generic code that
will build both for CONFIG_ACPI set and unset without adding explicit
compiler directives to it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> # on Haswell
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com> # for ATA and SDIO part
2013-11-14 23:14:43 +01:00
Rafael J. Wysocki dd6c26be3b Merge branch 'acpi-pm'
* acpi-pm:
  spi: attach/detach SPI device to the ACPI power domain
  i2c: attach/detach I2C client device to the ACPI power domain
  ACPI / PM: allow child devices to ignore parent power state
2013-10-28 01:17:49 +01:00
Lv Zheng a76e9bd89a i2c: attach/detach I2C client device to the ACPI power domain
If the I2C client device is enumerated from ACPI namespace it might have
ACPI methods that needs to be called in order to transition the device to
different power states (such as _PSx).

Implement this for I2C client devices by checking if the device has an ACPI
handle and if that's the case, attach it to the ACPI power domain. In
addition we make sure that the device is fully powered when its ->probe()
function gets called.

For non-ACPI devices this patch is a no-op.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-11 02:23:14 +02:00
Jean Delvare 47b6e477ed i2c: Not all adapters have a parent
The code in acpi_i2c_register_devices() assumes that all i2c adapters
have a parent. This is not necessarily the case, for example the
i2c-stub driver instantiate a virtual i2c adapter without a parent.
Check for this to avoid a NULL pointer deference.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-10 10:22:31 +02:00
Lars-Peter Clausen 0acc2b3213 i2c: Remove redundant 'driver' field from the i2c_client struct
The 'driver' field of the i2c_client struct is redundant. The same data can be
accessed through to_i2c_driver(client->dev.driver). The generated code for both
approaches in more or less the same.

E.g. on ARM the expression client->driver->command(...) generates

		...
		ldr     r3, [r0, #28]
		ldr     r3, [r3, #32]
		blx     r3
		...

and the expression to_i2c_driver(client->dev.driver)->command(...) generates

		...
		ldr     r3, [r0, #160]
    	ldr     r3, [r3, #-4]
    	blx     r3
		...

Other architectures will generate similar code.

All users of the 'driver' field outside of the I2C core have already been
converted. So this only leaves the core itself. This patch converts the
remaining few users in the I2C core and then removes the 'driver' field from the
i2c_client struct.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-03 22:28:31 +02:00
Mika Westerberg 55e71edb81 i2c: move ACPI helpers into the core
This follows what has already been done for the DeviceTree helpers. Move
the ACPI helpers from drivers/acpi/acpi_i2c.c to the I2C core and update
documentation accordingly.

This also solves a problem reported by Jerry Snitselaar that we can't build
the ACPI I2C helpers as a module.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23 10:22:29 +02:00
Wolfram Sang 687b81d083 i2c: move OF helpers into the core
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23 10:22:20 +02:00
Andy Lutomirski d63a9e851c i2c: Improve logging on failure to probe for ->class devices
While writing the i2c-imc driver, I noticed that the warning message
when the i2c core can't figure out how to probe is mostly useless.
This trivial patch improves it.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 14:49:58 +02:00
Sebastian Hesselbarth c66c4cc087 i2c: add sanity check to i2c_put_adapter
i2c_put_adapter dereferences i2c_adapter pointer passed without check
for NULL. This adds a check for non-NULL pointer to allow i2c_put_adapter
called with NULL and behave the same way i2c_release_client does already.
It allows to simplify drivers where you need to release the adapter
during probe failures.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-07 17:06:26 +02:00
Rafael J. Wysocki 45f0a85c82 PM / Runtime: Rework the "runtime idle" helper routine
The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0.  If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.

Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.

To reduce overall code bloat, make the changes described above.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
2013-06-03 21:49:52 +02:00
Alexander Sverdlin e9b526fe70 i2c: suppress lockdep warning on delete_device
i2c: suppress lockdep warning on delete_device

Since commit 846f99749a the following lockdep
warning is thrown in case i2c device is removed (via delete_device sysfs
attribute) which contains subdevices (e.g. i2c multiplexer):

=============================================
[ INFO: possible recursive locking detected ]
3.8.7-0-sampleversion-fct #8 Tainted: G           O
---------------------------------------------
bash/3743 is trying to acquire lock:
  (s_active#110){++++.+}, at: [<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8

but task is already holding lock:
  (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208

other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(s_active#110);
   lock(s_active#110);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

4 locks held by bash/3743:
  #0:  (&buffer->mutex){+.+.+.}, at: [<ffffffff802b3c3c>] sysfs_write_file+0x4c/0x208
  #1:  (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208
  #2:  (&adap->userspace_clients_lock/1){+.+.+.}, at: [<ffffffff80454a18>] i2c_sysfs_delete_device+0x90/0x238
  #3:  (&__lockdep_no_validate__){......}, at: [<ffffffff803dcc24>] device_release_driver+0x24/0x48

stack backtrace:
Call Trace:
[<ffffffff80575cc8>] dump_stack+0x8/0x34
[<ffffffff801b50fc>] __lock_acquire+0x161c/0x2110
[<ffffffff801b5c3c>] lock_acquire+0x4c/0x70
[<ffffffff802b60cc>] sysfs_addrm_finish+0x19c/0x1e0
[<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8
[<ffffffff802b7d8c>] sysfs_remove_group+0x64/0x148
[<ffffffff803d990c>] device_remove_attrs+0x9c/0x1a8
[<ffffffff803d9b1c>] device_del+0x104/0x1d8
[<ffffffff803d9c18>] device_unregister+0x28/0x70
[<ffffffff8045505c>] i2c_del_adapter+0x1cc/0x328
[<ffffffff8045802c>] i2c_del_mux_adapter+0x14/0x38
[<ffffffffc025c108>] pca954x_remove+0x90/0xe0 [pca954x]
[<ffffffff804542f8>] i2c_device_remove+0x80/0xe8
[<ffffffff803dca9c>] __device_release_driver+0x74/0xf8
[<ffffffff803dcc2c>] device_release_driver+0x2c/0x48
[<ffffffff803dbc14>] bus_remove_device+0x13c/0x1d8
[<ffffffff803d9b24>] device_del+0x10c/0x1d8
[<ffffffff803d9c18>] device_unregister+0x28/0x70
[<ffffffff80454b08>] i2c_sysfs_delete_device+0x180/0x238
[<ffffffff802b3cd4>] sysfs_write_file+0xe4/0x208
[<ffffffff8023ddc4>] vfs_write+0xbc/0x160
[<ffffffff8023df6c>] SyS_write+0x54/0xd8
[<ffffffff8013d424>] handle_sys64+0x44/0x64

The problem is already known for USB and PCI subsystems. The reason is that
delete_device attribute is defined statically in i2c-core.c and used for all
devices in i2c subsystem.

Discussion of original USB problem:
http://lkml.indiana.edu/hypermail/linux/kernel/1204.3/01160.html

Commit 356c05d58a introduced new macro to suppress
lockdep warnings for this special case and included workaround for USB code.

LKML discussion of the workaround:
http://lkml.indiana.edu/hypermail/linux/kernel/1205.1/03634.html

As i2c case is in principle the same, the same workaround could be used here.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-17 22:49:45 +02:00
Yijing Wang e5a7074a75 i2c: remove CONFIG_HOTPLUG ifdefs
CONFIG_HOTPLUG is going away as an option, cleanup CONFIG_HOTPLUG
ifdefs in i2c files.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-09 11:57:55 +02:00
Lars-Peter Clausen 71546300c8 i2c: Make return type of i2c_del_adapter() void
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>
2013-04-02 07:06:17 +02:00
Lars-Peter Clausen f5fb082295 i2c: i2c_del_adapter: Don't treat removing a non-registered adapter as error
Currently i2c_del_adapter() returns -EINVAL when it gets an adapter which is not
registered. But none of the users of i2c_del_adapter() depend on this behavior,
so for the sake of being able to sanitize the return type of i2c_del_adapter
argue, that the purpose of i2c_del_adapter() is to remove an I2C adapter from
the system. If the adapter is not registered in the first place this becomes a
no-op. So we can return success without having to do anything.

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>
2013-04-02 07:03:37 +02:00
Lars-Peter Clausen 19baba4cb6 i2c: Remove detach_adapter
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>
2013-04-02 07:03:28 +02:00
Viresh Kumar 5f9296ba21 i2c: Add bus recovery infrastructure
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>
2013-03-24 10:30:54 +01:00
Doug Anderson ee5c27440c i2c: core: Pick i2c bus number from dt alias if present
This allows you to get the equivalent functionality of
i2c_add_numbered_adapter() with all data in the device tree and no
special case code in your driver.  This is a common device tree
technique.

For quick reference, the FDT syntax for using an alias to provide an
ID looks like:
  aliases {
    i2c0 = &i2c_0;
    i2c1 = &i2c_1;
  };

Signed-off-by: Doug Anderson <dianders@chromium.org>
[wsa: removed one check from static function. We know our callers]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-03-24 10:30:53 +01:00
Tejun Heo e8c8d1bc06 idr: remove MAX_IDR_MASK and move left MAX_IDR_* into idr.c
MAX_IDR_MASK is another weirdness in the idr interface.  As idr covers
whole positive integer range, it's defined as 0x7fffffff or INT_MAX.

Its usage in idr_find(), idr_replace() and idr_remove() is bizarre.
They basically mask off the sign bit and operate on the rest, so if
the caller, by accident, passes in a negative number, the sign bit
will be masked off and the remaining part will be used as if that was
the input, which is worse than crashing.

The constant is visible in idr.h and there are several users in the
kernel.

* drivers/i2c/i2c-core.c:i2c_add_numbered_adapter()

  Basically used to test if adap->nr is a negative number which isn't
  -1 and returns -EINVAL if so.  idr_alloc() already has negative
  @start checking (w/ WARN_ON_ONCE), so this can go away.

* drivers/infiniband/core/cm.c:cm_alloc_id()
  drivers/infiniband/hw/mlx4/cm.c:id_map_alloc()

  Used to wrap cyclic @start.  Can be replaced with max(next, 0).
  Note that this type of cyclic allocation using idr is buggy.  These
  are prone to spurious -ENOSPC failure after the first wraparound.

* fs/super.c:get_anon_bdev()

  The ID allocated from ida is masked off before being tested whether
  it's inside valid range.  ida allocated ID can never be a negative
  number and the masking is unnecessary.

Update idr_*() functions to fail with -EINVAL when negative @id is
specified and update other MAX_IDR_MASK users as described above.

This leaves MAX_IDR_MASK without any user, remove it and relocate
other MAX_IDR_* constants to lib/idr.c.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Roland Dreier <roland@kernel.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: "Marciniszyn, Mike" <mike.marciniszyn@intel.com>
Cc: Jack Morgenstein <jackm@dev.mellanox.co.il>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Wolfram Sang <wolfram@the-dreams.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:20 -08:00
Tejun Heo 4ae42b0ff0 i2c: convert to idr_alloc()
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Wolfram Sang <wolfram@the-dreams.de>
Tested-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:16 -08:00
Tushar Behera c811093320 i2c: core: Remove definition of i2c_smbus_process_call
i2c_smbus_process_call has no users in the kernel, so this can be
removed. Documentation for the same has been updated accordingly.

Fixes following sparse warning.
drivers/i2c/i2c-core.c:1871:5: warning: symbol 'i2c_smbus_process_call'
was not declared. Should it be static?

[wsa: updated the documentation]

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2013-01-28 05:26:41 +01:00
Mika Westerberg 907ddf89d0 i2c / ACPI: add ACPI enumeration support
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>
2012-11-23 12:23:40 +01:00
Shubhrajyoti D 230da09435 i2c: Convert struct i2c_msg initialization to C99 format
Convert the struct i2c_msg initialization to C99 format. This makes
maintaining and editing the code simpler. Also helps once other fields
like transferred are added in future.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-10-05 22:23:52 +02:00
Fengguang Wu 125c4c706b idr: rename MAX_LEVEL to MAX_IDR_LEVEL
To avoid name conflicts:

  drivers/video/riva/fbdev.c:281:9: sparse: preprocessor token MAX_LEVEL redefined

While at it, also make the other names more consistent and add
parentheses.

[akpm@linux-foundation.org: repair fallout]
[sfr@canb.auug.org.au: IB/mlx4: fix for MAX_ID_MASK to MAX_IDR_MASK name change]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: walter harms <wharms@bfs.de>
Cc: Glauber Costa <glommer@parallels.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:04:56 +09:00
Jean Delvare 390946b172 i2c-core: Fix for lockdep validator
If kernel is compiled with CONFIG_PROVE_LOCKING the
validator raises an error when a multiplexer is removed
via sysfs and sub-clients are connected to it. This is a
false positive.
Documentation/lockdep-design.txt recommends to handle this
via calls to mutex_lock_nested().

Based on an earlier fix from Michael Lawnick.

Note that the extra code resolves to nothing unless
CONFIG_DEBUG_LOCK_ALLOC=y.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Michael Lawnick <ml.lawnick@gmx.de>
2012-09-10 10:14:02 +02:00
Linus Torvalds 6df419e45d Merge branch 'v4l_for_linus' of 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
  ...
2012-07-30 19:03:41 -07:00
Laurent Pinchart 72fc2c7f78 i2c: Fall back to emulated SMBus if the operation isn't supported natively
Adapter drivers might support only a subset of the SMBus operations
natively. Those drivers currently have to manually emulate unsupported
operations using I2C.

Make the i2c_smbus_xfer() function fall back to
i2c_smbus_xfer_emulated() when the adapter's .smbus_xfer() operation
returns -EOPNOTSUPP, like it already does when the .smbus_xfer()
operation isn't available at all.

[JD: Minor optimization.]

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-07-24 14:13:59 +02:00
Laurent Pinchart d47726c521 i2c: Add SCCB support
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>
2012-07-24 14:13:59 +02:00
Jean Delvare b37d2a3a75 [media] i2c: Export an unlocked flavor of i2c_transfer
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>
2012-06-29 19:03:25 -03:00
Stephen Warren 643dd09eb2 i2c: implement i2c_verify_adapter
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>
2012-05-12 14:28:16 +02:00
Jean Delvare 5694f8a888 i2c: Update the FSF address
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-03-26 21:47:19 +02:00
Wolfram Sang 834aa6f30c i2c-core: Comment says "transmitted" but means "received"
Fix that. Also convert this and the related comment to proper commenting
style.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-03-15 18:11:05 +01:00
Jean Delvare cbb4451404 i2c: Fix device name for 10-bit slave address
10-bit addresses overlap with traditional 7-bit addresses, leading in
device name collisions. Add an arbitrary offset to 10-bit addresses to
prevent this collision. The offset was chosen so that the address is
still easily recognizable.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
2011-11-23 11:33:07 +01:00
Grant Likely 488bf314bf i2c: Allow i2c_add_numbered_adapter() to assign a bus id
Currently, if an i2c bus driver supports both static and dynamic bus
ids, it needs to choose between calling i2c_add_numbered_adapter() and
i2c_add_adapter().  This patch makes i2c_add_numbered_adapter()
redirect to i2c_add_adapter() if the requested bus id is -1.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-07-25 17:49:43 +02:00
Jean Delvare a920ff41cb i2c: Improve deprecation warnings
When warning on the use of deprecated i2c_driver methods
attach_adapter and detach_adapter, mention the name of the driver
which needs to be updated.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-17 10:20:19 +02:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Jean Delvare fe6fc25857 i2c: Deprecate i2c_driver.attach_adapter and .detach_adapter
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>
2011-03-20 14:50:53 +01:00
Jean Delvare 7ae31482a8 i2c: Export i2c_for_each_dev
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>
2011-03-20 14:50:52 +01:00
Jean Delvare d735b34db3 i2c: make i2c_get_adapter prototype clearer
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>
2011-03-20 14:50:52 +01:00
Grant Likely c9e358dfc4 driver-core: remove conditionals around devicetree pointers
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>
2011-01-21 09:24:48 -07:00