ARM: at91/dt: introduce atmel,<chip>-dbgu

The DBGU is not a simple UART and we need to be able to distinguish it from the
other UARTs, in particular to get its address and check the chip id.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Documentation/devicetree/bindings/serial/atmel-usart.txt

 * Atmel Universal Synchronous Asynchronous Receiver/Transmitter (USART)
 
 Required properties:
-- compatible: Should be "atmel,<chip>-usart"
+- compatible: Should be "atmel,<chip>-usart" or "atmel,<chip>-dbgu"
   The compatible <chip> indicated will be the first SoC to support an
   additional mode or an USART new feature.
+  For the dbgu UART, use "atmel,<chip>-dbgu", "atmel,<chip>-usart"
 - reg: Should contain registers location and length
 - interrupts: Should contain interrupt
 - clock-names: tuple listing input clock names.

arch/arm/boot/dts/at91rm9200.dtsi

@@ -830,7 +830,7 @@ pioD: gpio@fffffa00 {
 			};
 
 			dbgu: serial@fffff200 {
-				compatible = "atmel,at91rm9200-usart";
+				compatible = "atmel,at91rm9200-dbgu", "atmel,at91rm9200-usart";
 				reg = <0xfffff200 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/at91sam9260.dtsi

@@ -753,7 +753,7 @@ pioC: gpio@fffff800 {
 			};
 
 			dbgu: serial@fffff200 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xfffff200 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/at91sam9261.dtsi

@@ -276,7 +276,7 @@ aic: interrupt-controller@fffff000 {
 			};
 
 			dbgu: serial@fffff200 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xfffff200 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/at91sam9263.dtsi

@@ -762,7 +762,7 @@ pioE: gpio@fffffa00 {
 			};
 
 			dbgu: serial@ffffee00 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xffffee00 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/at91sam9g45.dtsi

@@ -893,7 +893,7 @@ pioE: gpio@fffffa00 {
 			};
 
 			dbgu: serial@ffffee00 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xffffee00 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/at91sam9n12.dtsi

@@ -757,7 +757,7 @@ pioD: gpio@fffffa00 {
 			};
 
 			dbgu: serial@fffff200 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xfffff200 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/at91sam9rl.dtsi

@@ -377,7 +377,7 @@ aic: interrupt-controller@fffff000 {
 			};
 
 			dbgu: serial@fffff200 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xfffff200 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/at91sam9x5.dtsi

@@ -860,7 +860,7 @@ mmc1: mmc@f000c000 {
 			};
 
 			dbgu: serial@fffff200 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xfffff200 0x200>;
 				interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";

arch/arm/boot/dts/sama5d3.dtsi

@@ -439,7 +439,7 @@ ramc0: ramc@ffffea00 {
 			};
 
 			dbgu: serial@ffffee00 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xffffee00 0x200>;
 				interrupts = <2 IRQ_TYPE_LEVEL_HIGH 7>;
 				dmas = <&dma1 2 AT91_DMA_CFG_PER_ID(13)>,

arch/arm/boot/dts/sama5d4.dtsi

@@ -1064,7 +1064,7 @@ rtc@fc0686b0 {
 			};
 
 			dbgu: serial@fc069000 {
-				compatible = "atmel,at91sam9260-usart";
+				compatible = "atmel,at91sam9260-dbgu", "atmel,at91sam9260-usart";
 				reg = <0xfc069000 0x200>;
 				interrupts = <2 IRQ_TYPE_LEVEL_HIGH 7>;
 				pinctrl-names = "default";