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2021-07-20i2c: core: Disable client irq on reboot/shutdownDmitry Torokhov
[ Upstream commit b64210f2f7c11c757432ba3701d88241b2b98fb1 ] If an i2c client receives an interrupt during reboot or shutdown it may be too late to service it by making an i2c transaction on the bus because the i2c controller has already been shutdown. This can lead to system hangs if the i2c controller tries to make a transfer that is doomed to fail because the access to the i2c pins is already shut down, or an iommu translation has been torn down so i2c controller register access doesn't work. Let's simply disable the irq if there isn't a shutdown callback for an i2c client when there is an irq associated with the device. This will make sure that irqs don't come in later than the time that we can handle it. We don't do this if the i2c client device already has a shutdown callback because presumably they're doing the right thing and quieting the device so irqs don't come in after the shutdown callback returns. Reported-by: kernel test robot <lkp@intel.com> [swboyd@chromium.org: Dropped newline, added commit text, added interrupt.h for robot build error] Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-16i2c: turn recovery error on init to debugWolfram Sang
commit e409a6a3e0690efdef9b8a96197bc61ff117cfaf upstream. In some configurations, recovery is optional. So, don't throw an error when it is not used because e.g. pinctrl settings for recovery are not provided. Reword the message and make it debug output. Reported-by: Klaus Kudielka <klaus.kudielka@gmail.com> Tested-by: Klaus Kudielka <klaus.kudielka@gmail.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-01i2c: core: Call i2c_acpi_install_space_handler() before ↵Hans de Goede
i2c_acpi_register_devices() [ Upstream commit 21653a4181ff292480599dad996a2b759ccf050f ] Some ACPI i2c-devices _STA method (which is used to detect if the device is present) use autodetection code which probes which device is present over i2c. This requires the I2C ACPI OpRegion handler to be registered before we enumerate i2c-clients under the i2c-adapter. This fixes the i2c touchpad on the Lenovo ThinkBook 14-IIL and ThinkBook 15 IIL not getting an i2c-client instantiated and thus not working. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1842039 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-09-05i2c/mux, locking/core: Annotate the nested rt_mutex usagePeter Rosin
[ Upstream commit 7b94ea50514d1a0dc94f02723b603c27bc0ea597 ] If an i2c topology has instances of nested muxes, then a lockdep splat is produced when when i2c_parent_lock_bus() is called. Here is an example: ============================================ WARNING: possible recursive locking detected -------------------------------------------- insmod/68159 is trying to acquire lock: (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux] but task is already holding lock: (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(i2c_register_adapter#2); lock(i2c_register_adapter#2); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by insmod/68159: #0: (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux] stack backtrace: CPU: 13 PID: 68159 Comm: insmod Tainted: G O Call Trace: dump_stack+0x67/0x98 __lock_acquire+0x162e/0x1780 lock_acquire+0xba/0x200 rt_mutex_lock+0x44/0x60 i2c_parent_lock_bus+0x32/0x50 [i2c_mux] i2c_parent_lock_bus+0x3e/0x50 [i2c_mux] i2c_smbus_xfer+0xf0/0x700 i2c_smbus_read_byte+0x42/0x70 my2c_init+0xa2/0x1000 [my2c] do_one_initcall+0x51/0x192 do_init_module+0x62/0x216 load_module+0x20f9/0x2b50 SYSC_init_module+0x19a/0x1c0 SyS_init_module+0xe/0x10 do_syscall_64+0x6c/0x1a0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Reported-by: John Sperbeck <jsperbeck@google.com> Tested-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Deepa Dinamani <deepadinamani@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Chang <dpf@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Wolfram Sang <wsa@the-dreams.de> Link: http://lkml.kernel.org/r/20180720083914.1950-3-peda@axentia.se Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-03i2c: core: decrease reference count of device node in i2c_unregister_deviceLixin Wang
commit e0638fa400eaccf9fa8060f67140264c4e276552 upstream. Reference count of device node was increased in of_i2c_register_device, but without decreasing it in i2c_unregister_device. Then the added device node will never be released. Fix this by adding the of_node_put. Signed-off-by: Lixin Wang <alan.1.wang@nokia-sbell.com> Tested-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-14i2c: core: Make comment about I2C table requirement to reflect the codeJavier Martinez Canillas
I2C drivers were required to have an I2C device ID table even if were for devices that would only be registered using a specific firmware interface (e.g: OF or ACPI). But commit da10c06a044b ("i2c: Make I2C ID tables non-mandatory for DT'ed devices") changed the I2C core to relax the requirement and allow drivers to avoid defining this table. Unfortunately it only took into account drivers for OF-only devices and forgot about ACPI-only ones, and this was fixed by commit c64ffff7a9d1 ("i2c: core: Allow empty id_table in ACPI case as well"). But the latter didn't update the original comment, so it doesn't reflect what the code does now. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-07-31i2c: core: Allow empty id_table in ACPI case as wellAndy Shevchenko
For now empty ID table is not allowed with ACPI and prevents driver to be probed. Add a check to allow empty ID table. This introduces a helper i2c_acpi_match_device(). Note, we rename some static function in i2c-core-acpi.c to distinguish with public API. Fixes: da10c06a044b ("i2c: Make I2C ID tables non-mandatory for DT'ed devices") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Rajmohan Mani <rajmohan.mani@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> [wsa: needed to get some drivers probed again] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: reformat core-base file headerWolfram Sang
Finally, apply modern comment rules to the file header. The old style looked very non-Linuxish and challenged my eyes for some time now. I also added my own copyright for the period of me being the maintainer. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: remove unneeded includes from coreWolfram Sang
They seem like cruft to me. I couldn't find any evidence that something included from there is actually used. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out ACPI support into separate fileWolfram Sang
Removes some ifdeffery. Also add the new file to the relevant MAINTAINERS section. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out OF support into separate fileWolfram Sang
Also removes some ifdeffery. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out smbus support into separate fileWolfram Sang
Break out the exported SMBus functions and the emulation layer into a separate file. This also involved splitting up the tracing header into an I2C and an SMBus part. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out slave support into separate fileWolfram Sang
Also removes some ifdeffery. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: rename core source file to allow refactorizationWolfram Sang
The I2C core became quite huge and its monolithic structure makes maintenance hard. So, prepare to break out some functionality into separate files by renaming the source file. Note that we keep the resulting object name constant to avoid regressions. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>