On 25/09/2023 10:17, Herve Codina wrote:
Hi Krzysztof,
On Sat, 23 Sep 2023 19:39:49 +0200 Krzysztof Kozlowski krzysztof.kozlowski@linaro.org wrote:
On 22/09/2023 09:58, Herve Codina wrote:
The QMC (QUICC mutichannel controller) is a controller present in some PowerQUICC SoC such as MPC885. The QMC HDLC uses the QMC controller to transfer HDLC data.
Additionally, a framer can be connected to the QMC HDLC. If present, this framer is the interface between the TDM bus used by the QMC HDLC and the E1/T1 line. The QMC HDLC can use this framer to get information about the E1/T1 line and configure the E1/T1 line.
Signed-off-by: Herve Codina herve.codina@bootlin.com
.../soc/fsl/cpm_qe/fsl,cpm1-scc-qmc.yaml | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+)
diff --git a/Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-scc-qmc.yaml b/Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-scc-qmc.yaml index 82d9beb48e00..61dfd5ef7407 100644 --- a/Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-scc-qmc.yaml +++ b/Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-scc-qmc.yaml @@ -101,6 +101,27 @@ patternProperties: Channel assigned Rx time-slots within the Rx time-slots routed by the TSA to this cell.
compatible:const: fsl,qmc-hdlcWhy this is not a device/SoC specific compatible?
This compatible is present in a QMC channel. The parent node (the QMC itself) contains a compatible with device/SoC: --- 8< --- compatible: items: - enum: - fsl,mpc885-scc-qmc - fsl,mpc866-scc-qmc - const: fsl,cpm1-scc-qmc --- 8< ---
At the child level (ie QMC channel), I am not sure that adding device/SoC makes sense. This compatible indicates that the QMC channel is handled by the QMC HDLC driver. At this level, whatever the device/SoC, we have to be QMC compliant.
With these details, do you still think I need to change the child (channel) compatible ?
From OS point of view, you have a driver binding to this child-level compatible. How do you enforce Linux driver binding based on parent compatible? I looked at your next patch and I did not see it.
Best regards, Krzysztof