[PATCH v3 09/19] dt-bindings: nvmem: microchip-otpc: Add required clocks

Alexander Dahl ada at thorsis.com
Tue Jan 20 07:44:43 PST 2026


The OTPC requires both the peripheral clock through PMC and the main RC
oscillator.  Seemed to work without explicitly enabling those clocks on
sama7g5 before, but did not on sam9x60.

Older datasheets were not clear and explicit about this, but recent are,
e.g. SAMA7G5 series datasheet (DS60001765B),
section 30.4.1 Power Management:

> The OTPC is clocked through the Power Management Controller (PMC).
> The user must power on the main RC oscillator and enable the
> peripheral clock of the OTPC prior to reading or writing the OTP
> memory.

Link: https://lore.kernel.org/linux-clk/ec34efc2-2051-4b8a-b5d8-6e2fd5e08c28@microchip.com/T/#u
Signed-off-by: Alexander Dahl <ada at thorsis.com>
---

Notes:
    v3:
    - Removed clock-names (led to confusion, and not used by the driver anyways)
    - Removed redundant example
    
    v2:
    - new patch, not present in v1

 .../devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml b/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
index 9a7aaf64eef32..847dfb67c6b72 100644
--- a/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
+++ b/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
@@ -29,6 +29,11 @@ properties:
   reg:
     maxItems: 1
 
+  clocks:
+    items:
+      - description: main rc oscillator
+      - description: otpc peripheral clock
+
 required:
   - compatible
   - reg
@@ -37,6 +42,8 @@ unevaluatedProperties: false
 
 examples:
   - |
+    #include <dt-bindings/clock/at91.h>
+    #include <dt-bindings/clock/microchip,sama7g5-pmc.h>
     #include <dt-bindings/nvmem/microchip,sama7g5-otpc.h>
 
     otpc: efuse at e8c00000 {
@@ -44,6 +51,7 @@ examples:
         reg = <0xe8c00000 0xec>;
         #address-cells = <1>;
         #size-cells = <1>;
+        clocks = <&pmc PMC_TYPE_CORE SAMA7G5_PMC_MAIN_RC>, <&pmc PMC_TYPE_PERIPHERAL 67>;
 
         temperature_calib: calib at 1 {
             reg = <OTP_PKT(1) 76>;
-- 
2.47.3




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