Problem: The modem side processor keeps spinning for the spinlock acquired by the apps side processor for an I2C transaction when the apps side processor is suspend power collapsed.
Solution: The interrupts should be enabled before calling I2C on the Apps side.
Suspend() is already using a mutex_lock (which is also being used for the I2C transaction) which makes sure that the transaction is over before suspend happens. So, suspend power collapse should not happen until ongoing I2C transaction is done. And once suspend is called, any further I2C transaction cannot even acquire remote lock.
In such a situation, one should check that the interrupts are enabled when an I2C transaction on the apps side is being initiated. If the interrupts are disabled, then the driver cannot finish the transaction since the driver is interrupt driven and the lock acquired is never released. Thus, the interrupts should be enabled before calling I2C on the Apps side.
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