NFC: dts: st21nfca: Document ese-present & uicc-present DTS property

On st21nfca, the mechanism to enable a secure element needs to add 2
properties in order manage the SWP line correctly.

Document ese-present and uicc-present properties.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/net/nfc/st21nfca.txt b/Documentation/devicetree/bindings/net/nfc/st21nfca.txt
index db677fef56a9..7bb2e213d6f9 100644
--- a/Documentation/devicetree/bindings/net/nfc/st21nfca.txt
+++ b/Documentation/devicetree/bindings/net/nfc/st21nfca.txt
@@ -11,6 +11,10 @@ Required properties:
 Optional SoC Specific Properties:
 - pinctrl-names: Contains only one value - "default".
 - pintctrl-0: Specifies the pin control groups used for this controller.
+- ese-present: Specifies that an ese is physically connected to the nfc
+controller.
+- uicc-present: Specifies that the uicc swp signal can be physically
+connected to the nfc controller.
 
 Example (for ARM-based BeagleBoard xM with ST21NFCA on I2C2):
 
@@ -29,5 +33,8 @@ Example (for ARM-based BeagleBoard xM with ST21NFCA on I2C2):
                 interrupts = <2 IRQ_TYPE_LEVEL_LOW>;
 
                 enable-gpios = <&gpio5 29 GPIO_ACTIVE_HIGH>;
+
+                ese-present;
+                uicc-present;
         };
 };