Rename defines for sync event to avoid confusion

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Add spi error handler

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Handle error case if spi communication fails

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Fix too long line

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Remove insufficient error handling and fix possible race

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>