[PATCH v3 1/4] dt-bindings: net: can: Add poll-interval for MCAN

Judith Mendez jm at ti.com
Mon May 1 15:31:18 PDT 2023


On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
routed to A53 Linux, instead they will use software interrupt by
hrtimer. To enable timer method, interrupts should be optional so
remove interrupts property from required section and introduce
poll-interval property.

Signed-off-by: Judith Mendez <jm at ti.com>
---
Changelog:
v3:
 1. Move binding patch to first in series
 2. Update description for poll-interval
 3. Add oneOf to specify using interrupts/interrupt-names or poll-interval
 4. Fix example property: add comment below 'example'

v2:
  1. Add poll-interval property to enable timer polling method
  2. Add example using poll-interval property

 .../bindings/net/can/bosch,m_can.yaml         | 36 +++++++++++++++++--
 1 file changed, 34 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml b/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml
index 67879aab623b..c024ee49962c 100644
--- a/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml
+++ b/Documentation/devicetree/bindings/net/can/bosch,m_can.yaml
@@ -14,6 +14,13 @@ maintainers:
 allOf:
   - $ref: can-controller.yaml#
 
+oneOf:
+  - required:
+      - interrupts
+      - interrupt-names
+  - required:
+      - poll-interval
+
 properties:
   compatible:
     const: bosch,m_can
@@ -40,6 +47,14 @@ properties:
       - const: int1
     minItems: 1
 
+  poll-interval:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description: Enable hrtimer polling method for an M_CAN device.
+      If this property is defined in MCAN node, it tells the driver to
+      enable polling method for an MCAN device. If for an MCAN device,
+      hardware interrupt is found and hrtimer polling method is enabled,
+      the driver will use hardware interrupt method.
+
   clocks:
     items:
       - description: peripheral clock
@@ -122,8 +137,6 @@ required:
   - compatible
   - reg
   - reg-names
-  - interrupts
-  - interrupt-names
   - clocks
   - clock-names
   - bosch,mram-cfg
@@ -132,6 +145,7 @@ additionalProperties: false
 
 examples:
   - |
+    // Example with interrupts
     #include <dt-bindings/clock/imx6sx-clock.h>
     can at 20e8000 {
       compatible = "bosch,m_can";
@@ -149,4 +163,22 @@ examples:
       };
     };
 
+  - |
+    // Example with timer polling
+    #include <dt-bindings/clock/imx6sx-clock.h>
+    can at 20e8000 {
+      compatible = "bosch,m_can";
+      reg = <0x020e8000 0x4000>, <0x02298000 0x4000>;
+      reg-names = "m_can", "message_ram";
+      poll-interval;
+      clocks = <&clks IMX6SX_CLK_CANFD>,
+               <&clks IMX6SX_CLK_CANFD>;
+      clock-names = "hclk", "cclk";
+      bosch,mram-cfg = <0x0 0 0 32 0 0 0 1>;
+
+      can-transceiver {
+        max-bitrate = <5000000>;
+      };
+    };
+
 ...
-- 
2.17.1




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