dinesh wrote:
Hello,
I am stuck with a problem please help me.
I have allocated a buffer in ram and i want that if i playback something from user end then alsa library exchanges data with this buffer using memory mapping but for this i have to fill a
structure "snd_dma_buffer" in driver code but as i have told i dont want to use dma so i have to fill it manually with address of ram buffer.
Please tell me if it is possible if yes then help me.
Thanks in advance..
Regards, Dinesh Dua
I don't know the part of alsa you are working with so I can't answer your question. But I have some advice.
The list you are posting to is called alsa-devel. The devel stands for development, but it really isn't meant for development using alsa, but development of alsa. If the developers choose to they might answer your question. Or not. The other list for alsa is alsa-user, and this is for users of the api as well as end users of alsa. Again, you might have luck there with your query, or not.
However, your question is very ill formed. To you your problem is immediate and obvious, you understand the context, you know all the details. No one on this list does. You are more likely to get help if you explain the context of your question at a higher level. What are you trying to accomplish? How are you trying to accomplish it? Also put in snippets of code illustrating your approach where appropriate. This gives the information someone needs to answer your question. Someone might even be able to give you a better way to accomplish what you want to do. But no guarantees, this is a mailing list, no one is required to answer.
Your other alternative is to 'use the source'. All of the source for alsa is available, so you can look at that source to see if what you want to do is possible, and how it would have to be done. You could probably start with a grep of snd_dma_buffer in the library and driver source trees. This will likely bring up many hits, but you can then search for other context in those hits to find the area of interest. Then read the code to see how it works.
Slightly slower than getting a ready made answer, but surer. The code doesn't lie.