Re: Generic DMA-capable streaming device driver looking for home

[Jon Masters <jcm@jonmasters.org>]

On 04/20/2017 06:10 PM, Alex Williams wrote:
> Hi all,
> 
> We're writing a device driver and having some difficulty matching a
> subsystem to the driver/device properties. Can anyone help with
> direction?
> 
> These are some basic properties:
> 1) Device is used to carry generic data to/from userspace. It's a pair
>    of dumb streams with one sink and one source for each direction (no
>    addressable endpoints for the other side).
> 2) Data goes to/from a DMA engine in an FPGA at high throughput.
> 3) The driver enables userspace to queue multiple DMA-able buffers for
>    asynchronous, pipelined data transfer. We currently use the
>    videobuf2 API to provide the feature. We're not carrying video data
>    in general, though.
> 
> It's a piece of a software-defined radio system, and while it can carry
> data from DACs/ADCs, the device is only a generic transport. It doesn't
> know what data it's carrying, so neither would the driver.
> 
> Some guidance would be greatly appreciated. Thanks!

This might be close enough to hidma that Sinan would have suggestions?