Re: [PATCH] ARM: dts: at91: add serial MFD sub-node for usart

Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx> · Fri, 30 Oct 2020 14:38:38 +0100

On 30/10/2020 at 12:07, Codrin Ciubotariu wrote:
The "atmel,at91sam9260-usart" driver is a MFD driver, so it needs sub-nodes
to match the registered platform device. For this reason, we add a serial
subnode to all the "atmel,at91sam9260-usart" serial compatible nods. This
will also remove the boot warning:
"atmel_usart_serial: Failed to locate of_node [id: -2]"

I don't remember this warning was raised previously even if the MFD 
driver was added a while ago (Sept. 2018).

I would say it's due to 466a62d7642f ("mfd: core: Make a best effort 
attempt to match devices with the correct of_nodes") which was added on 
mid August and corrected with 22380b65dc70 ("mfd: mfd-core: Ensure 
disabled devices are ignored without error") but maybe not covering our 
case.

So, well, I don't know what's the best option to this change. Moreover, 
I would say that all other USART related properties go into the child 
not if there is a need for one.

Lee, I suspect that we're not the only ones experiencing this ugly 
warning during the boot log: can you point us out how to deal with it 
for our existing atmel_serial.c users?

Best regards,
  Nicolas

Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>
---
  arch/arm/boot/dts/at91-sam9x60ek.dts     |  3 +++
  arch/arm/boot/dts/at91rm9200.dtsi        | 15 ++++++++++++
  arch/arm/boot/dts/at91sam9261.dtsi       | 12 ++++++++++
  arch/arm/boot/dts/at91sam9261ek.dts      |  3 +++
  arch/arm/boot/dts/at91sam9263.dtsi       | 12 ++++++++++
  arch/arm/boot/dts/at91sam9g45.dtsi       | 15 ++++++++++++
  arch/arm/boot/dts/at91sam9n12.dtsi       | 15 ++++++++++++
  arch/arm/boot/dts/at91sam9rl.dtsi        | 15 ++++++++++++
  arch/arm/boot/dts/at91sam9x5.dtsi        | 18 ++++++++++++++
  arch/arm/boot/dts/at91sam9x5_usart3.dtsi |  3 +++
  arch/arm/boot/dts/sam9x60.dtsi           |  3 +++
  arch/arm/boot/dts/sama5d2.dtsi           | 30 ++++++++++++++++++++++++
  arch/arm/boot/dts/sama5d3.dtsi           | 18 ++++++++++++++
  arch/arm/boot/dts/sama5d3_uart.dtsi      |  6 +++++
  arch/arm/boot/dts/sama5d4.dtsi           | 30 ++++++++++++++++++++++++
  15 files changed, 198 insertions(+)

diff --git a/arch/arm/boot/dts/at91-sam9x60ek.dts b/arch/arm/boot/dts/at91-sam9x60ek.dts
index eae28b82c7fd..e317531f7363 100644
--- a/arch/arm/boot/dts/at91-sam9x60ek.dts
+++ b/arch/arm/boot/dts/at91-sam9x60ek.dts
@@ -280,6 +280,9 @@ AT91_XDMAC_DT_PERID(10))>,
  		atmel,use-dma-rx;
  		atmel,use-dma-tx;
  		status = "okay";
+		serial {
+			compatible = "atmel,at91rm9200-usart-serial";
+		};
  	};
  };
  
diff --git a/arch/arm/boot/dts/at91rm9200.dtsi b/arch/arm/boot/dts/at91rm9200.dtsi
index d1181ead18e5..2abb646f6b68 100644
--- a/arch/arm/boot/dts/at91rm9200.dtsi
+++ b/arch/arm/boot/dts/at91rm9200.dtsi
@@ -602,6 +602,9 @@ dbgu: serial@fffff200 {
  				clocks = <&pmc PMC_TYPE_CORE PMC_MCK>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart0: serial@fffc0000 {
@@ -615,6 +618,9 @@ usart0: serial@fffc0000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 6>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@fffc4000 {
@@ -628,6 +634,9 @@ usart1: serial@fffc4000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@fffc8000 {
@@ -641,6 +650,9 @@ usart2: serial@fffc8000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 8>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart3: serial@fffcc000 {
@@ -654,6 +666,9 @@ usart3: serial@fffcc000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 9>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usb1: gadget@fffb0000 {
diff --git a/arch/arm/boot/dts/at91sam9261.dtsi b/arch/arm/boot/dts/at91sam9261.dtsi
index 7adc36ca8a46..e9602378f92c 100644
--- a/arch/arm/boot/dts/at91sam9261.dtsi
+++ b/arch/arm/boot/dts/at91sam9261.dtsi
@@ -187,6 +187,9 @@ usart0: serial@fffb0000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 6>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@fffb4000 {
@@ -200,6 +203,9 @@ usart1: serial@fffb4000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@fffb8000{
@@ -213,6 +219,9 @@ usart2: serial@fffb8000{
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 8>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			ssc0: ssc@fffbc000 {
@@ -307,6 +316,9 @@ dbgu: serial@fffff200 {
  				clocks = <&pmc PMC_TYPE_CORE PMC_MCK>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			pinctrl@fffff400 {
diff --git a/arch/arm/boot/dts/at91sam9261ek.dts b/arch/arm/boot/dts/at91sam9261ek.dts
index beed819609e8..fae5d408268d 100644
--- a/arch/arm/boot/dts/at91sam9261ek.dts
+++ b/arch/arm/boot/dts/at91sam9261ek.dts
@@ -176,6 +176,9 @@ tsc2046@2 {
  
  			dbgu: serial@fffff200 {
  				status = "okay";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			watchdog@fffffd40 {
diff --git a/arch/arm/boot/dts/at91sam9263.dtsi b/arch/arm/boot/dts/at91sam9263.dtsi
index fe45d96239c9..e4d370b582c8 100644
--- a/arch/arm/boot/dts/at91sam9263.dtsi
+++ b/arch/arm/boot/dts/at91sam9263.dtsi
@@ -546,6 +546,9 @@ dbgu: serial@ffffee00 {
  				clocks = <&pmc PMC_TYPE_CORE PMC_MCK>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart0: serial@fff8c000 {
@@ -559,6 +562,9 @@ usart0: serial@fff8c000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@fff90000 {
@@ -572,6 +578,9 @@ usart1: serial@fff90000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 8>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@fff94000 {
@@ -585,6 +594,9 @@ usart2: serial@fff94000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 9>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			ssc0: ssc@fff98000 {
diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index 19fc748a87c5..8aad026f10ec 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -682,6 +682,9 @@ dbgu: serial@ffffee00 {
  				clocks = <&pmc PMC_TYPE_CORE PMC_MCK>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart0: serial@fff8c000 {
@@ -695,6 +698,9 @@ usart0: serial@fff8c000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@fff90000 {
@@ -708,6 +714,9 @@ usart1: serial@fff90000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 8>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@fff94000 {
@@ -721,6 +730,9 @@ usart2: serial@fff94000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 9>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart3: serial@fff98000 {
@@ -734,6 +746,9 @@ usart3: serial@fff98000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 10>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			macb0: ethernet@fffbc000 {
diff --git a/arch/arm/boot/dts/at91sam9n12.dtsi b/arch/arm/boot/dts/at91sam9n12.dtsi
index 0785389f5507..f83d1a313edf 100644
--- a/arch/arm/boot/dts/at91sam9n12.dtsi
+++ b/arch/arm/boot/dts/at91sam9n12.dtsi
@@ -599,6 +599,9 @@ dbgu: serial@fffff200 {
  				clocks = <&pmc PMC_TYPE_CORE PMC_MCK>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			ssc0: ssc@f0010000 {
@@ -624,6 +627,9 @@ usart0: serial@f801c000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 5>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@f8020000 {
@@ -635,6 +641,9 @@ usart1: serial@f8020000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 6>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@f8024000 {
@@ -646,6 +655,9 @@ usart2: serial@f8024000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart3: serial@f8028000 {
@@ -657,6 +669,9 @@ usart3: serial@f8028000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 8>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			i2c0: i2c@f8010000 {
diff --git a/arch/arm/boot/dts/at91sam9rl.dtsi b/arch/arm/boot/dts/at91sam9rl.dtsi
index 5653e70c84b4..5480b6542c6a 100644
--- a/arch/arm/boot/dts/at91sam9rl.dtsi
+++ b/arch/arm/boot/dts/at91sam9rl.dtsi
@@ -183,6 +183,9 @@ usart0: serial@fffb0000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 6>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@fffb4000 {
@@ -196,6 +199,9 @@ usart1: serial@fffb4000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@fffb8000 {
@@ -209,6 +215,9 @@ usart2: serial@fffb8000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 8>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart3: serial@fffbc000 {
@@ -222,6 +231,9 @@ usart3: serial@fffbc000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 9>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			ssc0: ssc@fffc0000 {
@@ -353,6 +365,9 @@ dbgu: serial@fffff200 {
  				clocks = <&pmc PMC_TYPE_CORE PMC_MCK>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			pinctrl@fffff400 {
diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index 4cdb05079cc7..52aa49b007d1 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -683,6 +683,9 @@ dbgu: serial@fffff200 {
  				clocks = <&pmc PMC_TYPE_CORE PMC_MCK>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart0: serial@f801c000 {
@@ -697,6 +700,9 @@ usart0: serial@f801c000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 5>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@f8020000 {
@@ -711,6 +717,9 @@ usart1: serial@f8020000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 6>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@f8024000 {
@@ -725,6 +734,9 @@ usart2: serial@f8024000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			i2c0: i2c@f8010000 {
@@ -781,6 +793,9 @@ uart0: serial@f8040000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 15>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			uart1: serial@f8044000 {
@@ -792,6 +807,9 @@ uart1: serial@f8044000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 16>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			adc0: adc@f804c000 {
diff --git a/arch/arm/boot/dts/at91sam9x5_usart3.dtsi b/arch/arm/boot/dts/at91sam9x5_usart3.dtsi
index 098d3fef5c37..a80593188ac1 100644
--- a/arch/arm/boot/dts/at91sam9x5_usart3.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5_usart3.dtsi
@@ -53,6 +53,9 @@ usart3: serial@f8028000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 8>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  		};
  	};
diff --git a/arch/arm/boot/dts/sam9x60.dtsi b/arch/arm/boot/dts/sam9x60.dtsi
index 84066c1298df..ab4d80134d86 100644
--- a/arch/arm/boot/dts/sam9x60.dtsi
+++ b/arch/arm/boot/dts/sam9x60.dtsi
@@ -598,6 +598,9 @@ AT91_XDMAC_DT_PERID(28))>,
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 47>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			pinctrl: pinctrl@fffff400 {
diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
index 2ddc85dff8ce..26f231147d21 100644
--- a/arch/arm/boot/dts/sama5d2.dtsi
+++ b/arch/arm/boot/dts/sama5d2.dtsi
@@ -444,6 +444,9 @@ AT91_XDMAC_DT_PERID(35))>,
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 24>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			uart1: serial@f8020000 {
@@ -460,6 +463,9 @@ AT91_XDMAC_DT_PERID(37))>,
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 25>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			uart2: serial@f8024000 {
@@ -476,6 +482,9 @@ AT91_XDMAC_DT_PERID(39))>,
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 26>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			i2c0: i2c@f8028000 {
@@ -536,6 +545,9 @@ AT91_XDMAC_DT_PER_IF(1) |
  					dma-names = "tx", "rx";
  					atmel,fifo-size = <32>;
  					status = "disabled";
+					serial {
+						compatible = "atmel,at91rm9200-usart-serial";
+					};
  				};
  
  				spi2: spi@400 {
@@ -606,6 +618,9 @@ AT91_XDMAC_DT_PER_IF(1) |
  					dma-names = "tx", "rx";
  					atmel,fifo-size = <32>;
  					status = "disabled";
+					serial {
+						compatible = "atmel,at91rm9200-usart-serial";
+					};
  				};
  
  				spi3: spi@400 {
@@ -771,6 +786,9 @@ AT91_XDMAC_DT_PERID(41))>,
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 27>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			uart4: serial@fc00c000 {
@@ -787,6 +805,9 @@ AT91_XDMAC_DT_PERID(43))>,
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 28>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			flx2: flexcom@fc010000 {
@@ -815,6 +836,9 @@ AT91_XDMAC_DT_PER_IF(1) |
  					dma-names = "tx", "rx";
  					atmel,fifo-size = <32>;
  					status = "disabled";
+					serial {
+						compatible = "atmel,at91rm9200-usart-serial";
+					};
  				};
  
  				spi4: spi@400 {
@@ -885,6 +909,9 @@ AT91_XDMAC_DT_PER_IF(1) |
  					dma-names = "tx", "rx";
  					atmel,fifo-size = <32>;
  					status = "disabled";
+					serial {
+						compatible = "atmel,at91rm9200-usart-serial";
+					};
  				};
  
  				spi5: spi@400 {
@@ -956,6 +983,9 @@ AT91_XDMAC_DT_PER_IF(1) |
  					dma-names = "tx", "rx";
  					atmel,fifo-size = <32>;
  					status = "disabled";
+					serial {
+						compatible = "atmel,at91rm9200-usart-serial";
+					};
  				};
  
  				spi6: spi@400 {
diff --git a/arch/arm/boot/dts/sama5d3.dtsi b/arch/arm/boot/dts/sama5d3.dtsi
index 86137f8d2b45..1791de52d1c3 100644
--- a/arch/arm/boot/dts/sama5d3.dtsi
+++ b/arch/arm/boot/dts/sama5d3.dtsi
@@ -203,6 +203,9 @@ usart0: serial@f001c000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 12>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@f0020000 {
@@ -217,6 +220,9 @@ usart1: serial@f0020000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 13>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			uart0: serial@f0024000 {
@@ -228,6 +234,9 @@ uart0: serial@f0024000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 16>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			pwm0: pwm@f002c000 {
@@ -389,6 +398,9 @@ usart2: serial@f8020000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 14>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart3: serial@f8024000 {
@@ -403,6 +415,9 @@ usart3: serial@f8024000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 15>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			sha@f8034000 {
@@ -497,6 +512,9 @@ dbgu: serial@ffffee00 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 2>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			aic: interrupt-controller@fffff000 {
diff --git a/arch/arm/boot/dts/sama5d3_uart.dtsi b/arch/arm/boot/dts/sama5d3_uart.dtsi
index a3eaba995cf4..b9f83b771a09 100644
--- a/arch/arm/boot/dts/sama5d3_uart.dtsi
+++ b/arch/arm/boot/dts/sama5d3_uart.dtsi
@@ -45,6 +45,9 @@ uart0: serial@f0024000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 16>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			uart1: serial@f8028000 {
@@ -56,6 +59,9 @@ uart1: serial@f8028000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 17>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  		};
  	};
diff --git a/arch/arm/boot/dts/sama5d4.dtsi b/arch/arm/boot/dts/sama5d4.dtsi
index 04f24cf752d3..0627fa8cdaf4 100644
--- a/arch/arm/boot/dts/sama5d4.dtsi
+++ b/arch/arm/boot/dts/sama5d4.dtsi
@@ -284,6 +284,9 @@ uart0: serial@f8004000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 27>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			ssc0: ssc@f8008000 {
@@ -443,6 +446,9 @@ usart0: serial@f802c000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 6>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart1: serial@f8030000 {
@@ -461,6 +467,9 @@ usart1: serial@f8030000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 7>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			mmc1: mmc@fc000000 {
@@ -496,6 +505,9 @@ uart1: serial@fc004000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 28>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart2: serial@fc008000 {
@@ -514,6 +526,9 @@ usart2: serial@fc008000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 29>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart3: serial@fc00c000 {
@@ -532,6 +547,9 @@ usart3: serial@fc00c000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 30>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			usart4: serial@fc010000 {
@@ -550,6 +568,9 @@ usart4: serial@fc010000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 31>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			ssc1: ssc@fc014000 {
@@ -568,6 +589,9 @@ ssc1: ssc@fc014000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 49>;
  				clock-names = "pclk";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			spi1: spi@fc018000 {
@@ -588,6 +612,9 @@ spi1: spi@fc018000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 38>;
  				clock-names = "spi_clk";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  			spi2: spi@fc01c000 {
@@ -794,6 +821,9 @@ dbgu: serial@fc069000 {
  				clocks = <&pmc PMC_TYPE_PERIPHERAL 45>;
  				clock-names = "usart";
  				status = "disabled";
+				serial {
+					compatible = "atmel,at91rm9200-usart-serial";
+				};
  			};
  
  



--
Nicolas Ferre






