On Thu, Jan 29, 2009 at 1:18 AM, Hans-Christian Egtvedt hans-christian.egtvedt@atmel.com wrote:
Should I after the open and hw_params calls be ready to handle any change at all regarding DMA buffer address, periods and/or number of periods?
You would need to do this, if you allocate your DMA buffer in the hw_params function. However, I recommend that you allocate it in the _new/_open function instead (I can't remember what it's called) for the maximum size possible, and in _hw_params, just remember what the size is supposed to be. That way, you won't need to free/realloc your DMA buffer. Trust me, it's a lot easier this way.
Take a look at commit bf9c8c9ddef7ef761ae9747349175adad0ef16ce, where I modify my driver to move the DMA allocation from _hw_params to _open.