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authorWolfram Sang2019-04-03 14:40:09 +0200
committerWolfram Sang2019-04-16 13:08:11 +0200
commit83c42212d2544625b85f44a07d0ad96323e69250 (patch)
treef9fbca3a009f6e40eecce87ed42fc49eeef059dd /drivers
parenti2c: core: remove use of in_atomic() (diff)
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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')
-rw-r--r--drivers/i2c/i2c-core-base.c11
-rw-r--r--drivers/i2c/i2c-core-smbus.c7
-rw-r--r--drivers/i2c/i2c-core.h12
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,