diff options
| author | Wolfram Sang <wsa+renesas@sang-engineering.com> | 2019-04-03 14:40:09 +0200 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2019-04-16 13:08:11 +0200 |
| commit | 83c42212d2544625b85f44a07d0ad96323e69250 (patch) | |
| tree | f9fbca3a009f6e40eecce87ed42fc49eeef059dd /drivers/i2c | |
| parent | i2c: core: remove use of in_atomic() (diff) | |
| download | linux-83c42212d2544625b85f44a07d0ad96323e69250.tar.xz linux-83c42212d2544625b85f44a07d0ad96323e69250.zip | |
i2c: core: use I2C locking behaviour also for SMBUS
If I2C transfers are executed in atomic contexts, trylock is used
instead of lock. This behaviour was missing for SMBUS, although a lot of
transfers are of SMBUS type, either emulated or direct. So, factor out
the locking routine into a helper and use it for I2C and SMBUS.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/i2c-core-base.c | 11 | ||||
| -rw-r--r-- | drivers/i2c/i2c-core-smbus.c | 7 | ||||
| -rw-r--r-- | drivers/i2c/i2c-core.h | 12 |
3 files changed, 21 insertions, 9 deletions
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index f8502064cd6b..ad14f38a67e4 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -1946,14 +1946,9 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) * one (discarding status on the second message) or errno * (discarding status on the first one). */ - if (i2c_in_atomic_xfer_mode()) { - ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT); - if (!ret) - /* I2C activity is ongoing. */ - return -EAGAIN; - } else { - i2c_lock_bus(adap, I2C_LOCK_SEGMENT); - } + ret = __i2c_lock_bus_helper(adap); + if (ret) + return ret; ret = __i2c_transfer(adap, msgs, num); i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c index 132119112596..357e083e8f45 100644 --- a/drivers/i2c/i2c-core-smbus.c +++ b/drivers/i2c/i2c-core-smbus.c @@ -20,6 +20,8 @@ #include <linux/i2c-smbus.h> #include <linux/slab.h> +#include "i2c-core.h" + #define CREATE_TRACE_POINTS #include <trace/events/smbus.h> @@ -530,7 +532,10 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, { s32 res; - i2c_lock_bus(adapter, I2C_LOCK_SEGMENT); + res = __i2c_lock_bus_helper(adapter); + if (res) + return res; + res = __i2c_smbus_xfer(adapter, addr, flags, read_write, command, protocol, data); i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT); diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h index 9d8526415b26..deea47c576e5 100644 --- a/drivers/i2c/i2c-core.h +++ b/drivers/i2c/i2c-core.h @@ -39,6 +39,18 @@ static inline bool i2c_in_atomic_xfer_mode(void) return system_state > SYSTEM_RUNNING && irqs_disabled(); } +static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap) +{ + int ret = 0; + + if (i2c_in_atomic_xfer_mode()) + ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN; + else + i2c_lock_bus(adap, I2C_LOCK_SEGMENT); + + return ret; +} + #ifdef CONFIG_ACPI const struct acpi_device_id * i2c_acpi_match_device(const struct acpi_device_id *matches, |