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| author | Benjamin Bara <benjamin.bara@skidata.com> | 2024-01-04 09:17:08 +0100 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2024-01-06 14:10:10 +0100 |
| commit | a3368e1186e3ce8e38f78cbca019622095b1f331 (patch) | |
| tree | 3aaecfd23523436d4c8afb3585e37e8b2c960844 /drivers/i2c | |
| parent | 5cb23af38916fccde98f7a999b0b6f8c4ec34a3e (diff) | |
| download | lwn-a3368e1186e3ce8e38f78cbca019622095b1f331.tar.gz lwn-a3368e1186e3ce8e38f78cbca019622095b1f331.zip | |
i2c: core: Fix atomic xfer check for non-preempt config
Since commit aa49c90894d0 ("i2c: core: Run atomic i2c xfer when
!preemptible"), the whole reboot/power off sequence on non-preempt kernels
is using atomic i2c xfer, as !preemptible() always results to 1.
During device_shutdown(), the i2c might be used a lot and not all busses
have implemented an atomic xfer handler. This results in a lot of
avoidable noise, like:
[ 12.687169] No atomic I2C transfer handler for 'i2c-0'
[ 12.692313] WARNING: CPU: 6 PID: 275 at drivers/i2c/i2c-core.h:40 i2c_smbus_xfer+0x100/0x118
...
Fix this by allowing non-atomic xfer when the interrupts are enabled, as
it was before.
Link: https://lore.kernel.org/r/20231222230106.73f030a5@yea
Link: https://lore.kernel.org/r/20240102150350.3180741-1-mwalle@kernel.org
Link: https://lore.kernel.org/linux-i2c/13271b9b-4132-46ef-abf8-2c311967bb46@mailbox.org/
Fixes: aa49c90894d0 ("i2c: core: Run atomic i2c xfer when !preemptible")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Benjamin Bara <benjamin.bara@skidata.com>
Tested-by: Michael Walle <mwalle@kernel.org>
Tested-by: Tor Vic <torvic9@mailbox.org>
[wsa: removed a comment which needs more work, code is ok]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/i2c-core.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h index 05b8b8dfa9bd..36587f38dff3 100644 --- a/drivers/i2c/i2c-core.h +++ b/drivers/i2c/i2c-core.h @@ -3,6 +3,7 @@ * i2c-core.h - interfaces internal to the I2C framework */ +#include <linux/kconfig.h> #include <linux/rwsem.h> struct i2c_devinfo { @@ -29,7 +30,8 @@ int i2c_dev_irq_from_resources(const struct resource *resources, */ static inline bool i2c_in_atomic_xfer_mode(void) { - return system_state > SYSTEM_RUNNING && !preemptible(); + return system_state > SYSTEM_RUNNING && + (IS_ENABLED(CONFIG_PREEMPT_COUNT) ? !preemptible() : irqs_disabled()); } static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap) |