Hi Philipp,
Thanks for the comments! I'll revise it and send a v4. Here is my reply to some parts of your question.
On Mon, Aug 05, 2013 at 12:07:02PM +0200, Philipp Zabel wrote:
This looks to me like a case of configuration data in the device tree. Couldn't the tx/rx clock source be determined automatically or at least the SoC specific clock sources to the mux be known to the driver, so that we can use clock phandles here?
What happens if a different tx-clk-source is needed for 48 kHz than for 44.1 kHz?
You are right about the case. I'll try to figure out a nicer way, including for the different sample-rate.
Do we already have anything for this in the kernel? It could also be done using:
u8 tmp = input;
tmp = ((tmp & 0b10101010) >> 1) | ((tmp << 1) & 0b10101010); tmp = ((tmp & 0b11001100) >> 2) | ((tmp << 2) & 0b11001100); tmp = ((tmp & 0b11110000) >> 4) | ((tmp << 4) & 0b11110000);return tmp;
I was also wondering this question but I couldn't find it. And obviously your algorithm is better :)
In principle, it should also be possible to let the SDMA engine only take the FIFOs' MSBs for S16_LE. Is this a limitation of the SDMA ROM script?
You are right about the idea and the inference.