[PATCH 6/7] dt-bindings: spi: stm32: add stm32h7 st,spi-slave-underrun property

[Valentin Caron <valentin.caron@foss.st.com>]

This property is used to enable and configure stm32h7 SPI controller to
handle underrun that could appear in slave mode.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
---
 .../devicetree/bindings/spi/st,stm32-spi.yaml     |  8 ++++++++
 MAINTAINERS                                       |  1 +
 include/dt-bindings/spi/spi-stm32.h               | 15 +++++++++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 include/dt-bindings/spi/spi-stm32.h

diff --git a/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml b/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml
index 1d26fa2658c5..e946ea71a247 100644
--- a/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml
+++ b/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml
@@ -28,6 +28,7 @@ allOf:
       properties:
         st,spi-midi-ns: false
         spi-slave: false
+        st,spi-slave-underrun: false
 
 properties:
   "#address-cells": true
@@ -70,6 +71,13 @@ properties:
       In case of spi-slave defined, if <0>, indicate that SS should be
       detected via the dedicated HW pin
 
+  st,spi-slave-underrun:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    description:
+      First parameter enables and selects slave underrun reaction.
+      Refer to "dt-bindings/spi/spi-stm32.h" for the supported values.
+      Second parameter is the pattern in case of SPI_SEND_PATTERN mode.
+
 patternProperties:
   "^[a-zA-Z][a-zA-Z0-9,+\\-._]{0,63}@[0-9a-f]+$":
     type: object
diff --git a/MAINTAINERS b/MAINTAINERS
index 007a9cdb9cc8..9dcf861834fd 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19790,6 +19790,7 @@ M:	Alain Volmat <alain.volmat@foss.st.com>
 L:	linux-spi@vger.kernel.org
 S:	Maintained
 F:	drivers/spi/spi-stm32.c
+F:	include/dt-bindings/spi/spi-stm32.h
 
 ST STPDDC60 DRIVER
 M:	Daniel Nilsson <daniel.nilsson@flex.com>
diff --git a/include/dt-bindings/spi/spi-stm32.h b/include/dt-bindings/spi/spi-stm32.h
new file mode 100644
index 000000000000..260109fd1631
--- /dev/null
+++ b/include/dt-bindings/spi/spi-stm32.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-3-Clause) */
+/*
+ * This header provides constants for STM32_SPI bindings.
+ */
+
+#ifndef _DT_BINDINGS_SPI_SPI_STM32_H
+#define _DT_BINDINGS_SPI_SPI_STM32_H
+
+/* st,spi-slave-underrun first parameter */
+#define SPI_NO_ACTION			        0
+#define SPI_SEND_PATTERN		        1
+#define SPI_REPEAT_LAST_RECEIVED_DATA	        2
+#define SPI_REPEAT_LAST_TRANSMITTED_DATA        3
+
+#endif
-- 
2.25.1