On Wed, Nov 11, 2009 at 03:10:57PM +0800, Barry Song wrote:
Due to some hardware dependence issues, some devices maybe require different suspend/resume execution order for CPU and Codec DAI to make sure the hardware can work normally after executing sleep and wakeup.
Are there any actual systems that this solves problems for - if so, what are the problems? I don't think this solution is general enough to be scalable, it'll work for one particular use case but if we get further reorderings needed it'll become difficult to manage.
If we're going to be doing anything with this I think it would be much better to use the pm_link infrastructure which will be appearing in 2.6.34. This should allow us to provide arbatrary ordering of device level suspend and resume.