[PATCH v4 07/16] dt-bindings: nvmem: microchip-otpc: Add required clocks

[Alexander Dahl <ada@thorsis.com>]

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.

Confirmed by Microchip based on vendor internal documentation (see link).

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

Notes:
    v4:
    - Add clocks to the required section of the binding (Claudiu)
    
    v3:
    - Removed clock-names (led to confusion, and not used by the driver anyways)
    - Removed redundant example
    
    v2:
    - new patch, not present in v1

 .../bindings/nvmem/microchip,sama7g5-otpc.yaml           | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml b/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
index cc25f2927682e..bef0246a79f16 100644
--- a/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
+++ b/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
@@ -27,14 +27,22 @@ properties:
   reg:
     maxItems: 1
 
+  clocks:
+    items:
+      - description: main rc oscillator
+      - description: otpc peripheral clock
+
 required:
   - compatible
   - reg
+  - clocks
 
 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@e8c00000 {
@@ -42,6 +50,7 @@ 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@1 {
             reg = <OTP_PKT(1) 76>;
-- 
2.47.3