[PATCH wireless-next v2 2/2] dt-bindings: net: wireless: wfx: discourage OOB IRQ with SDIO

[Jérôme Pouiller]

The WFxxx device provides an SDIO interface. In addition to the usual
in-band SDIO IRQ, the device also supports an out-of-band IRQ line.

However, using the OOB IRQ with SDIO requires to poll the control
register during the device initialization. This polling is unreliable:
if an IRQ is raised while the host reads the control register, the
device is lost and only a reset allows to recover it.

There is no way to fix this in software. So, warn the user that this
setup should be reserved to debug.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>
---
 Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml b/Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml
index 6c0888ae4c4e1..60dfe257eadc2 100644
--- a/Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml
+++ b/Documentation/devicetree/bindings/net/wireless/silabs,wfx.yaml
@@ -50,6 +50,9 @@ properties:
       used, this property is required. When SDIO is used, the "in-band"
       interrupt provided by the SDIO bus is used unless an interrupt is defined
       in the Device Tree.
+
+      The hardware suffers from a limitation when this property is used with
+      SDIO. OOB IRQ with SDIO should only be used for debug.
     maxItems: 1
 
   reset-gpios:
-- 
2.47.3