On 14/12/02 9:09, David E. Box wrote:
Select Intel Baytrail platforms support PMIC's whose i2c bus may be controlled exclusively by platform hardware. This patch set adds support for i2c bus locking to the designware core and provides a driver module for managing the lock on these platforms. Since the lock on these systems isn't enumerable outside of the i2c platform driver, the locking functions are assigned at compile time.
Have you ever look into the hwspinlock framework? It seems to me that such an exclusive operation between CPUs and external hardware blocks is exactly what hwspinlock is for. Further more hwspinlock takes care of exclusiveness between SMP cores. Ideally I would expect i2c-designware to have hwspinlock lock/unlock API calls on one I2C transaction, but it's not necessarily the case. Introducing such platform hooks (acquire_lock and release_lock) and keeping actual exclusive operataion outside the driver might be good for various usecases/platforms. Shinya -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
