linux/drivers/i2c
Hans de Goede c57813b8b2 i2c: designware: Lock the adapter while setting the suspended flag
Lock the adapter while setting the suspended flag, to ensure that other
locked code always sees the change immediately, rather then possibly using
a stale value.

This involves splitting the suspend/resume callbacks into separate runtime
and normal suspend/resume calls. This is necessary because i2c_dw_xfer()
will get called by the i2c-core with the adapter locked and it in turn
calls the runtime-resume callback through pm_runtime_get_sync().

So the runtime versions of the suspend/resume callbacks cannot take
the adapter-lock. Note this patch simply makes the runtime suspend/resume
callbacks not deal with the suspended flag at all. During runtime the
pm_runtime_get_sync() from i2c_dw_xfer() will always ensure that the
adapter is resumed when necessary.

The suspended flag check is only necessary to check proper suspend/resume
ordering during normal suspend/resume which makes the pm_runtime_get_sync()
call a no-op.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-03-01 16:30:53 +01:00
..
algos i2c: algo: bit: use new macro to specifiy capabilities 2021-01-22 09:59:21 +01:00
busses i2c: designware: Lock the adapter while setting the suspended flag 2022-03-01 16:30:53 +01:00
muxes i2c: mux: gpio: Use array_size() helper 2021-11-23 11:54:41 +01:00
i2c-boardinfo.c i2c: Remove support for dangling device properties 2021-04-10 21:43:02 +02:00
i2c-core-acpi.c i2c: ACPI: Replace acpi_bus_get_device() 2022-02-07 17:00:08 +01:00
i2c-core-base.c i2c: core: Use generic_handle_irq_safe() in i2c_handle_smbus_host_notify(). 2022-03-01 15:58:41 +01:00
i2c-core-of.c
i2c-core-slave.c i2c: slave: add sanity check when unregistering 2020-07-28 18:37:17 +02:00
i2c-core-smbus.c i2c: smbus: Check for parent device before dereference 2022-02-19 12:37:20 +01:00
i2c-core.h i2c: don't expose function which is only used internally 2022-02-15 09:58:57 +01:00
i2c-dev.c i2c: validate user data in compat ioctl 2021-12-31 14:28:22 +01:00
i2c-mux.c
i2c-slave-eeprom.c i2c: busses: Use fallthrough pseudo-keyword 2020-07-23 22:04:08 +02:00
i2c-slave-testunit.c i2c: testunit: add support for block process calls 2021-02-12 11:11:04 +01:00
i2c-smbus.c i2c: smbus: Use device_*() functions instead of of_*() 2022-01-28 21:56:34 +01:00
i2c-stub.c i2c: stub: remove definition of DEBUG 2021-01-17 13:00:10 +01:00
Kconfig i2c: add slave testunit driver 2020-09-21 11:02:17 +02:00
Makefile i2c: add slave testunit driver 2020-09-21 11:02:17 +02:00