Hi Marc,

On 13/04/21 6:45 pm, Rob Herring wrote:

On Tue, Apr 13, 2021 at 2:41 AM Marc Kleine-Budde [off-list ref] wrote:

quoted

On 12.04.2021 12:49:56, Rob Herring wrote:

quoted

On Mon, Apr 12, 2021 at 12:19:30PM +0200, Marc Kleine-Budde wrote:

quoted

On 4/9/21 3:40 PM, Aswath Govindraju wrote:

quoted

Add binding documentation for TI TCAN104x CAN transceivers.

Signed-off-by: Aswath Govindraju <redacted>
---
 .../bindings/phy/ti,tcan104x-can.yaml         | 56 +++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml

diff --git a/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml b/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
new file mode 100644
index 000000000000..4abfc30a97d0
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml

@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/phy/ti,tcan104x-can.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: TCAN104x CAN TRANSCEIVER PHY
+
+maintainers:
+  - Aswath Govindraju <a-govindraju@ti.com>
+
+properties:
+  $nodename:
+    pattern: "^tcan104x-phy"
+
+  compatible:
+    enum:
+      - ti,tcan1042
+      - ti,tcan1043

Can you create a generic standby only and a generic standby and enable transceiver?

As a fallback compatible fine, but no generic binding please. A generic
binding can't describe any timing requirements between the 2 GPIO as
well as supplies when someone wants to add those (and they will).

Right - that makes sense.

So, I need not add any new compatible strings right because as a
fallback the existing compatible strings can be used, as there are no
timing constraints on them.

Thanks,
Aswath

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+
+  '#phy-cells':
+    const: 0
+
+  standby-gpios:
+    description:
+      gpio node to toggle standby signal on transceiver
+    maxItems: 1
+
+  enable-gpios:
+    description:
+      gpio node to toggle enable signal on transceiver
+    maxItems: 1
+
+  max-bitrate:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      max bit rate supported in bps

We already have 'max-speed' for serial devices, use that.

There is already the neither Ethernet PHY (PHYLINK/PHYLIB) nor generic
PHY (GENERIC_PHY) can-transceiver binding
Documentation/devicetree/bindings/net/can/can-transceiver.yaml which
specifies max-bitrate. I don't have strong feelings whether to use
max-bitrate or max-speed.

Okay, max-bitrate is fine.

quoted

Speaking about Ethernet PHYs, what are to pros and cons to use the
generic PHY compared to the Ethernet PHY infrastructure?

For higher speed ethernet, both are used. There's the serdes phy and
the ethernet phy with serdes phy using the generic phy binding. For
CAN, it probably comes down to what's a better fit.

Rob