On Fri, Jan 27, 2023 at 05:53:49PM +0100, Krzysztof Kozlowski wrote: > On 27/01/2023 17:46, Chris Morgan wrote: > > On Fri, Jan 27, 2023 at 11:24:03AM +0100, Krzysztof Kozlowski wrote: > >> On 26/01/2023 17:55, Chris Morgan wrote: > >>> From: Chris Morgan <macromorgan@xxxxxxxxxxx> > >>> > >>> Add compatible string for RTL8821CS for existing Realtek Bluetooth > >>> driver. > >>> > >>> Signed-off-by: Chris Morgan <macromorgan@xxxxxxxxxxx> > >>> --- > >>> Documentation/devicetree/bindings/net/realtek-bluetooth.yaml | 1 + > >>> 1 file changed, 1 insertion(+) > >>> > >> > >> Based on your driver it is compatible with rtl8822cs, so you can > >> indicate it in the binding and use just one of_device_id entry. > > > > It's very similar, and uses some of the same constants, but has a > > different firmware. I assumed the firmware difference is enough to > > require it to be differentiated, but I wasn't sure. You are saying > > it does not? I just want to be clear. > > If by "differentiated" you mean "incompatible", then depends: > 1. You have firmware-name property to indicate the firmware to load and > then you can use one compatible to bind and just load different firmware, > 2. If device variant is autodectable, it's compatible. > > realtek,rtl8723ds-bt also was added to the driver uselessly... Gotcha. They are incompatible, but the driver should be able to autodetect each device as best I can tell. In fact all of the devices listed in the bindings should be autodetectable by the driver (again, as best I can tell). Honestly though that's assuming I'm using the correct firmware, which is why I have this tagged as an RFC. I'm really hoping to get Realtek's attention for them to chime in to confirm I'm using the most recent firmware and under what license/terms the firmware can be redistributed so that the firmware may be added to linux-firmware. Assuming everything is good though, I can resubmit V2 and instead of adding a new compatible just noting that the 8822CS and 8821CS use the same bindings. Thank you. > > Best regards, > Krzysztof >