Hi Jyri, On Mon, Mar 04, 2019 at 04:29:17PM +0200, Jyri Sarha wrote: > On 04/03/2019 14:42, Laurent Pinchart wrote: > > On Wed, Feb 27, 2019 at 11:54:18PM +0200, Jyri Sarha wrote: > >> Changes since first version: > >> - Moved reviewed patches to front: > >> - drm/bridge: sii902x: add input_bus_flags > >> - drm/bridge: sii902x: Set output mode to HDMI or DVI according to EDID > >> - drm/bridge: sii902x: pixel clock unit is 10kHz instead of 1kHz > >> - Added a new fix: > >> - drm/bridge: sii902x: Select I2C_MUX > >> - Applied some review suggestions to > >> - drm/bridge: sii902x: Implement HDMI audio support > >> - use clock-names property to name mclk > >> - move comment describing added mutex to struct sii902x and improve it > >> - cleanup sii902x_mute() > >> - cleanup sii902x_select_mclk_div() > >> - fix condition for checking ENABLE_BIT from i2s_fifo_routing in > >> sii902x_audio_codec_init() > >> > >> Still to do > >> > >> - Agree on i2s wires to HDMI audio fifo routing in dts. > >> > >> The current scheme is quite straight forward, but there is maybe > >> there is even more straight forward solutions like: > >> > >> audio-fifo-enable = <1 1 1 1>; > >> audio-i2s-pin-to-fifo = <0 1 2 3>; > >> > >> Meaning that all fifos are enabled and SD0 is routed to fifo 0, SD1 > >> to fifo 1, etc. I am not sure if the channel swap functionality > >> should show in dts binding. > > > > Please forgive my lack of audio knowledge, but it this a system > > description that should be encoded in DT, or a policy that should be > > handled purely in software (either fully inside the kernel or with the > > help of userspace) ? > > This property describes how many i2s wires are connected to sii902x and > in what order, so I think it belongs to DTS. That would belong to DT, yes. We have solved a similar problem with CSI-2 receivers, where the number of data lanes and their mapping can often be configured. See the definition of the data-lanes property in Documentation/devicetree/bindings/media/video-interfaces.txt for more information. How about using similar bindings ? It would also solve Andrzej's concerns that you don't describe the audio connection in DT. > One might of course wonder why anybody would put the i2s wires to any > other order than 0 <-> 0, 1 <-> 1, 2 <-> 2, and 3 <-> 3, but then a > again I've seen weirder board designs. It can be useful to simplify signal routing on the board. -- Regards, Laurent Pinchart
