[PATCH v2 3/4] dt-bindings: i2c-stm32: add SMBus Alert bindings

[Alain Volmat]

Add a new binding of the i2c-stm32f7 driver to enable the handling
of the SMBUS-Alert.

The I2C/SMBUS framework already provides a mechanism to enable SMBus-Alert
by naming an IRQ line "smbus_alert". However, on stm32, the SMBus-Alert is
part of the i2c IRQ. Using the smbus_alert naming here would lead to having
2 handlers (the handler of the driver and the smbus_alert handler
from I2C/SMBUS framework) on the unique i2c IRQ of the stm32. Meaning that
the smbus_alert handler would get called for all IRQ generated by the stm32
I2C controller.

For that reason, the smbus_alert IRQ naming cannot be used and a dedicated
binding is introduced.

Signed-off-by: Alain Volmat <alain.volmat at st.com>
---
v2: Clarify commit message

 Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml b/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml
index f2fcbb361180..6fde046fae5e 100644
--- a/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml
+++ b/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml
@@ -36,6 +36,10 @@ allOf:
             minItems: 3
             maxItems: 3
 
+        st,smbus-alert:
+          description: Enable the SMBus Alert feature
+          $ref: /schemas/types.yaml#/definitions/flag
+
   - if:
       properties:
         compatible:
-- 
2.7.4