[PATCH v2 04/10] arm64: dts: actions: *do not merge* disable sps node from S700

[PATCH v2 04/10] arm64: dts: actions: *do not merge* disable sps node from S700

[Amit Singh Tomar]

After commit 7cdf8446ed1d ("arm64: dts: actions: Add pinctrl node for
Actions Semi S700") following error has been observed while booting
Linux on Cubieboard7-lite(based on S700 SoC).

[    0.257415] pinctrl-s700 e01b0000.pinctrl: can't request region for
resource [mem 0xe01b0000-0xe01b0fff]
[    0.266902] pinctrl-s700: probe of e01b0000.pinctrl failed with error -16

This is due to the fact that memory range for "sps" power domain controller
clashes with pinctrl.

This commit disable "sps" to avoid this conflict and let us test DMA and MMC
related changes.

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Changes since v1:
	* No change.
Changes since RFC:
        * kept as do not merge.
---
 arch/arm64/boot/dts/actions/s700.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/actions/s700.dtsi b/arch/arm64/boot/dts/actions/s700.dtsi
index 2006ad5424fa..0397c5dd3dec 100644
--- a/arch/arm64/boot/dts/actions/s700.dtsi
+++ b/arch/arm64/boot/dts/actions/s700.dtsi
@@ -220,6 +220,7 @@
 			compatible = "actions,s700-sps";
 			reg = <0x0 0xe01b0100 0x0 0x100>;
 			#power-domain-cells = <1>;
+			status = "disabled";
 		};
 
 		timer: timer@e024c000 {
-- 
2.7.4

[PATCH v2 05/10] dt-bindings: dmaengine: convert Actions Semi Owl SoCs bindings to yaml

[Amit Singh Tomar]

Converts the device tree bindings for the Actions Semi Owl SoCs DMA
Controller over to YAML schemas.

It also adds new compatible string "actions,s700-dma".

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Change since v1:
	* Updated the description field to reflect
	  only the necessary information.
	* replaced the maxItems field with description for each 
          controller attribute(except interrupts).
	* Replaced the clock macro with number to keep the example
          as independent as possible.
	  	
 New patch, was not there in RFC.
---
 Documentation/devicetree/bindings/dma/owl-dma.txt  | 47 -------------
 Documentation/devicetree/bindings/dma/owl-dma.yaml | 76 ++++++++++++++++++++++
 2 files changed, 76 insertions(+), 47 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/dma/owl-dma.txt
 create mode 100644 Documentation/devicetree/bindings/dma/owl-dma.yaml

diff --git a/Documentation/devicetree/bindings/dma/owl-dma.txt b/Documentation/devicetree/bindings/dma/owl-dma.txt
deleted file mode 100644
index 03e9bb12b75f..000000000000
--- a/Documentation/devicetree/bindings/dma/owl-dma.txt
+++ /dev/null
@@ -1,47 +0,0 @@
-* Actions Semi Owl SoCs DMA controller
-
-This binding follows the generic DMA bindings defined in dma.txt.
-
-Required properties:
-- compatible: Should be "actions,s900-dma".
-- reg: Should contain DMA registers location and length.
-- interrupts: Should contain 4 interrupts shared by all channel.
-- #dma-cells: Must be <1>. Used to represent the number of integer
-              cells in the dmas property of client device.
-- dma-channels: Physical channels supported.
-- dma-requests: Number of DMA request signals supported by the controller.
-                Refer to Documentation/devicetree/bindings/dma/dma.txt
-- clocks: Phandle and Specifier of the clock feeding the DMA controller.
-
-Example:
-
-Controller:
-                dma: dma-controller@e0260000 {
-                        compatible = "actions,s900-dma";
-                        reg = <0x0 0xe0260000 0x0 0x1000>;
-                        interrupts = <GIC_SPI 57 IRQ_TYPE_LEVEL_HIGH>,
-                                     <GIC_SPI 58 IRQ_TYPE_LEVEL_HIGH>,
-                                     <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>,
-                                     <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
-                        #dma-cells = <1>;
-                        dma-channels = <12>;
-                        dma-requests = <46>;
-                        clocks = <&clock CLK_DMAC>;
-                };
-
-Client:
-
-DMA clients connected to the Actions Semi Owl SoCs DMA controller must
-use the format described in the dma.txt file, using a two-cell specifier
-for each channel.
-
-The two cells in order are:
-1. A phandle pointing to the DMA controller.
-2. The channel id.
-
-uart5: serial@e012a000 {
-        ...
-        dma-names = "tx", "rx";
-        dmas = <&dma 26>, <&dma 27>;
-        ...
-};
diff --git a/Documentation/devicetree/bindings/dma/owl-dma.yaml b/Documentation/devicetree/bindings/dma/owl-dma.yaml
new file mode 100644
index 000000000000..82e7d261e967
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/owl-dma.yaml
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/owl-dma.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Actions Semi Owl SoCs DMA controller
+
+description: |
+  The OWL DMA is a general-purpose direct memory access controller capable of
+  supporting 10 and 12 independent DMA channels for S700 and S900 SoCs
+  respectively.
+
+maintainers:
+  - Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+
+allOf:
+  - $ref: "dma-controller.yaml#"
+
+properties:
+  compatible:
+    enum:
+      - actions,s900-dma
+      - actions,s700-dma
+
+  reg:
+    description:
+      DMA registers location and length.
+
+  interrupts:
+    description:
+      controller supports 4 interrupts, which are freely assignable to the
+      DMA channels.
+    maxItems: 4
+
+  "#dma-cells":
+    const: 1
+
+  dma-channels:
+    description:
+      Physical channels supported.
+
+  dma-requests:
+    description:
+      Number of DMA request signals supported by the controller.
+
+  clocks:
+    description:
+      Phandle and Specifier of the clock feeding the DMA controller.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - "#dma-cells"
+  - dma-channels
+  - dma-requests
+  - clocks
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    dma: dma-controller@e0260000 {
+        compatible = "actions,s900-dma";
+        reg = <0x0 0xe0260000 0x0 0x1000>;
+        interrupts = <GIC_SPI 57 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 58 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
+        #dma-cells = <1>;
+        dma-channels = <12>;
+        dma-requests = <46>;
+        clocks = <&clock 22>;
+    };
+
+...
-- 
2.7.4

[PATCH v2 06/10] arm64: dts: actions: Add DMA Controller for S700

[Amit Singh Tomar]

This commit adds DAM controller present on Actions S700, it differs from
S900 in terms of number of dma channels and requests.

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Changes since v1:
        * No Change.
Changes since RFC:
        * No Change.
---
 arch/arm64/boot/dts/actions/s700.dtsi | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm64/boot/dts/actions/s700.dtsi b/arch/arm64/boot/dts/actions/s700.dtsi
index 0397c5dd3dec..56f2f84812cb 100644
--- a/arch/arm64/boot/dts/actions/s700.dtsi
+++ b/arch/arm64/boot/dts/actions/s700.dtsi
@@ -245,5 +245,18 @@
 				     <GIC_SPI 39 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>;
 		};
+
+		dma: dma-controller@e0230000 {
+			compatible = "actions,s700-dma";
+			reg = <0x0 0xe0230000 0x0 0x1000>;
+			interrupts = <GIC_SPI 57 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 58 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
+			#dma-cells = <1>;
+			dma-channels = <10>;
+			dma-requests = <44>;
+			clocks = <&cmu CLK_DMAC>;
+		};
 	};
 };
-- 
2.7.4

[PATCH v2 07/10] dt-bindings: reset: s700: Add binding constants for mmc

[Amit Singh Tomar]

This commit adds device tree binding reset constants for mmc controller
present on Actions S700 Soc.

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Changes since v1:
	* No change.
Changes since RFC:
        * added Rob's acked-by tag
---
 include/dt-bindings/reset/actions,s700-reset.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/dt-bindings/reset/actions,s700-reset.h b/include/dt-bindings/reset/actions,s700-reset.h
index 5e3b16b8ef53..a3118de6d7aa 100644
--- a/include/dt-bindings/reset/actions,s700-reset.h
+++ b/include/dt-bindings/reset/actions,s700-reset.h
@@ -30,5 +30,8 @@
 #define RESET_UART4				20
 #define RESET_UART5				21
 #define RESET_UART6				22
+#define RESET_SD0				23
+#define RESET_SD1				24
+#define RESET_SD2				25
 
 #endif /* __DT_BINDINGS_ACTIONS_S700_RESET_H */
-- 
2.7.4

[PATCH v2 08/10] dt-bindings: mmc: owl: add compatible string actions,s700-mmc

[Amit Singh Tomar]

The commit adds a new SoC specific compatible string "actions,s700-mmc"
in combination with more generic string "actions,owl-mmc".

Placement order of these strings should abide by the principle of
"from most specific to most general".

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
	* Newly added patch in v2.
---
 Documentation/devicetree/bindings/mmc/owl-mmc.yaml | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/mmc/owl-mmc.yaml b/Documentation/devicetree/bindings/mmc/owl-mmc.yaml
index 12b40213426d..9604ef695585 100644
--- a/Documentation/devicetree/bindings/mmc/owl-mmc.yaml
+++ b/Documentation/devicetree/bindings/mmc/owl-mmc.yaml
@@ -14,7 +14,11 @@ maintainers:
 
 properties:
   compatible:
-    const: actions,owl-mmc
+    oneOf:
+      - const: actions,owl-mmc
+      - items:
+          - const: actions,s700-mmc
+          - const: actions,owl-mmc
 
   reg:
     maxItems: 1
-- 
2.7.4

[PATCH v2 09/10] arm64: dts: actions: Add MMC controller support for S700

[Amit Singh Tomar]

This commits adds support for MMC controllers present on Actions S700 SoC,
there are 3 MMC controllers in this SoC which can be used for accessing
SD/EMMC/SDIO cards.

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Changes since v1:
	* Added SoC specific compatibe string.
Changes since RFC:
        * No change.
---
 arch/arm64/boot/dts/actions/s700.dtsi | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/arch/arm64/boot/dts/actions/s700.dtsi b/arch/arm64/boot/dts/actions/s700.dtsi
index 56f2f84812cb..0d3ff315b00e 100644
--- a/arch/arm64/boot/dts/actions/s700.dtsi
+++ b/arch/arm64/boot/dts/actions/s700.dtsi
@@ -258,5 +258,38 @@
 			dma-requests = <44>;
 			clocks = <&cmu CLK_DMAC>;
 		};
+
+		mmc0: mmc@e0210000 {
+			compatible = "actions,s700-mmc", "actions,owl-mmc";
+			reg = <0x0 0xe0210000 0x0 0x4000>;
+			interrupts = <GIC_SPI 42 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&cmu CLK_SD0>;
+			resets = <&cmu RESET_SD0>;
+			dmas = <&dma 2>;
+			dma-names = "mmc";
+			status = "disabled";
+		};
+
+		mmc1: mmc@e0214000 {
+			compatible = "actions,s700-mmc", "actions,owl-mmc";
+			reg = <0x0 0xe0214000 0x0 0x4000>;
+			interrupts = <GIC_SPI 43 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&cmu CLK_SD1>;
+			resets = <&cmu RESET_SD1>;
+			dmas = <&dma 3>;
+			dma-names = "mmc";
+			status = "disabled";
+		};
+
+		mmc2: mmc@e0218000 {
+			compatible = "actions,s700-mmc", "actions,owl-mmc";
+			reg = <0x0 0xe0218000 0x0 0x4000>;
+			interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&cmu CLK_SD2>;
+			resets = <&cmu RESET_SD2>;
+			dmas = <&dma 4>;
+			dma-names = "mmc";
+			status = "disabled";
+		};
 	};
 };
-- 
2.7.4

[PATCH v2 10/10] arm64: dts: actions: Add uSD support for Cubieboard7

[Amit Singh Tomar]

This commit adds uSD support for Cubieboard7 board based on Actions Semi
S700 SoC. SD0 is connected to uSD slot. Since there is no PMIC support
added yet, fixed regulator has been used as a regulator node.

Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Changes since v1:
	* No change.
Changes since RFC:
        * No change.
---
 arch/arm64/boot/dts/actions/s700-cubieboard7.dts | 41 ++++++++++++++++++++++++
 arch/arm64/boot/dts/actions/s700.dtsi            |  1 +
 2 files changed, 42 insertions(+)

diff --git a/arch/arm64/boot/dts/actions/s700-cubieboard7.dts b/arch/arm64/boot/dts/actions/s700-cubieboard7.dts
index 63e375cd9eb4..ec117eb12f3a 100644
--- a/arch/arm64/boot/dts/actions/s700-cubieboard7.dts
+++ b/arch/arm64/boot/dts/actions/s700-cubieboard7.dts
@@ -13,6 +13,7 @@
 
 	aliases {
 		serial3 = &uart3;
+		mmc0 = &mmc0;
 	};
 
 	chosen {
@@ -28,6 +29,23 @@
 		device_type = "memory";
 		reg = <0x1 0xe0000000 0x0 0x0>;
 	};
+
+	/* Fixed regulator used in the absence of PMIC */
+	vcc_3v1: vcc-3v1 {
+		compatible = "regulator-fixed";
+		regulator-name = "fixed-3.1V";
+		regulator-min-microvolt = <3100000>;
+		regulator-max-microvolt = <3100000>;
+	};
+
+	/* Fixed regulator used in the absence of PMIC */
+	sd_vcc: sd-vcc {
+		compatible = "regulator-fixed";
+		regulator-name = "fixed-3.1V";
+		regulator-min-microvolt = <3100000>;
+		regulator-max-microvolt = <3100000>;
+		regulator-always-on;
+	};
 };
 
 &i2c0 {
@@ -81,6 +99,14 @@
 			bias-pull-up;
 		};
 	};
+
+	mmc0_default: mmc0_default {
+		pinmux {
+			groups = "sd0_d0_mfp", "sd0_d1_mfp", "sd0_d2_d3_mfp",
+				 "sd0_cmd_mfp", "sd0_clk_mfp";
+			function = "sd0";
+		};
+	};
 };
 
 &timer {
@@ -90,3 +116,18 @@
 &uart3 {
 	status = "okay";
 };
+
+/* uSD */
+&mmc0 {
+	status = "okay";
+	pinctrl-names = "default";
+	pinctrl-0 = <&mmc0_default>;
+	cd-gpios = <&pinctrl 120 GPIO_ACTIVE_LOW>;
+	no-sdio;
+	no-mmc;
+	no-1-8-v;
+	bus-width = <4>;
+	vmmc-supply = <&sd_vcc>;
+	vqmmc-supply = <&sd_vcc>;
+};
+
diff --git a/arch/arm64/boot/dts/actions/s700.dtsi b/arch/arm64/boot/dts/actions/s700.dtsi
index 0d3ff315b00e..18700aeb8d2b 100644
--- a/arch/arm64/boot/dts/actions/s700.dtsi
+++ b/arch/arm64/boot/dts/actions/s700.dtsi
@@ -4,6 +4,7 @@
  */
 
 #include <dt-bindings/clock/actions,s700-cmu.h>
+#include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <dt-bindings/reset/actions,s700-reset.h>
 
-- 
2.7.4

Re: [PATCH v2 07/10] dt-bindings: reset: s700: Add binding constants for mmc

[Rob Herring]

On Tue, May 19, 2020 at 11:49:25PM +0530, Amit Singh Tomar wrote:
> This commit adds device tree binding reset constants for mmc controller
> present on Actions S700 Soc.
> 
> Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
> ---
> Changes since v1:
> 	* No change.
> Changes since RFC:
>         * added Rob's acked-by tag

And dropped??

> ---
>  include/dt-bindings/reset/actions,s700-reset.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/include/dt-bindings/reset/actions,s700-reset.h b/include/dt-bindings/reset/actions,s700-reset.h
> index 5e3b16b8ef53..a3118de6d7aa 100644
> --- a/include/dt-bindings/reset/actions,s700-reset.h
> +++ b/include/dt-bindings/reset/actions,s700-reset.h
> @@ -30,5 +30,8 @@
>  #define RESET_UART4				20
>  #define RESET_UART5				21
>  #define RESET_UART6				22
> +#define RESET_SD0				23
> +#define RESET_SD1				24
> +#define RESET_SD2				25
>  
>  #endif /* __DT_BINDINGS_ACTIONS_S700_RESET_H */
> -- 
> 2.7.4
> 

[PATCH v2 07/10] dt-bindings: reset: s700: Add binding constants for mmc

[Amit Singh Tomar]

This commit adds device tree binding reset constants for mmc controller
present on Actions S700 Soc.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
---
Changes since v1:
	* No change.
Changes since RFC:
        * added Rob's acked-by tag
---
 include/dt-bindings/reset/actions,s700-reset.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/dt-bindings/reset/actions,s700-reset.h b/include/dt-bindings/reset/actions,s700-reset.h
index 5e3b16b8ef53..a3118de6d7aa 100644
--- a/include/dt-bindings/reset/actions,s700-reset.h
+++ b/include/dt-bindings/reset/actions,s700-reset.h
@@ -30,5 +30,8 @@
 #define RESET_UART4				20
 #define RESET_UART5				21
 #define RESET_UART6				22
+#define RESET_SD0				23
+#define RESET_SD1				24
+#define RESET_SD2				25
 
 #endif /* __DT_BINDINGS_ACTIONS_S700_RESET_H */
-- 
2.7.4

Re: [PATCH v2 07/10] dt-bindings: reset: s700: Add binding constants for mmc

[Amit Tomer]

Hi,

On Wed, May 20, 2020 at 12:03 AM Rob Herring <robh@kernel.org> wrote:
>
> On Tue, May 19, 2020 at 11:49:25PM +0530, Amit Singh Tomar wrote:
> > This commit adds device tree binding reset constants for mmc controller
> > present on Actions S700 Soc.
> >
> > Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
> > ---
> > Changes since v1:
> >       * No change.
> > Changes since RFC:
> >         * added Rob's acked-by tag
>
> And dropped??

Sorry, I just forgot to add it.

Thanks
-Amit

Re: [PATCH v2 05/10] dt-bindings: dmaengine: convert Actions Semi Owl SoCs bindings to yaml

[Rob Herring]

On Tue, May 19, 2020 at 11:49:23PM +0530, Amit Singh Tomar wrote:
> Converts the device tree bindings for the Actions Semi Owl SoCs DMA
> Controller over to YAML schemas.
> 
> It also adds new compatible string "actions,s700-dma".
> 
> Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
> ---
> Change since v1:
> 	* Updated the description field to reflect
> 	  only the necessary information.
> 	* replaced the maxItems field with description for each 
>           controller attribute(except interrupts).
> 	* Replaced the clock macro with number to keep the example
>           as independent as possible.
> 	  	
>  New patch, was not there in RFC.
> ---
>  Documentation/devicetree/bindings/dma/owl-dma.txt  | 47 -------------
>  Documentation/devicetree/bindings/dma/owl-dma.yaml | 76 ++++++++++++++++++++++
>  2 files changed, 76 insertions(+), 47 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/dma/owl-dma.txt
>  create mode 100644 Documentation/devicetree/bindings/dma/owl-dma.yaml
> 
> diff --git a/Documentation/devicetree/bindings/dma/owl-dma.txt b/Documentation/devicetree/bindings/dma/owl-dma.txt
> deleted file mode 100644
> index 03e9bb12b75f..000000000000
> --- a/Documentation/devicetree/bindings/dma/owl-dma.txt
> +++ /dev/null
> @@ -1,47 +0,0 @@
> -* Actions Semi Owl SoCs DMA controller
> -
> -This binding follows the generic DMA bindings defined in dma.txt.
> -
> -Required properties:
> -- compatible: Should be "actions,s900-dma".
> -- reg: Should contain DMA registers location and length.
> -- interrupts: Should contain 4 interrupts shared by all channel.
> -- #dma-cells: Must be <1>. Used to represent the number of integer
> -              cells in the dmas property of client device.
> -- dma-channels: Physical channels supported.
> -- dma-requests: Number of DMA request signals supported by the controller.
> -                Refer to Documentation/devicetree/bindings/dma/dma.txt
> -- clocks: Phandle and Specifier of the clock feeding the DMA controller.
> -
> -Example:
> -
> -Controller:
> -                dma: dma-controller@e0260000 {
> -                        compatible = "actions,s900-dma";
> -                        reg = <0x0 0xe0260000 0x0 0x1000>;
> -                        interrupts = <GIC_SPI 57 IRQ_TYPE_LEVEL_HIGH>,
> -                                     <GIC_SPI 58 IRQ_TYPE_LEVEL_HIGH>,
> -                                     <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>,
> -                                     <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
> -                        #dma-cells = <1>;
> -                        dma-channels = <12>;
> -                        dma-requests = <46>;
> -                        clocks = <&clock CLK_DMAC>;
> -                };
> -
> -Client:
> -
> -DMA clients connected to the Actions Semi Owl SoCs DMA controller must
> -use the format described in the dma.txt file, using a two-cell specifier
> -for each channel.
> -
> -The two cells in order are:
> -1. A phandle pointing to the DMA controller.
> -2. The channel id.
> -
> -uart5: serial@e012a000 {
> -        ...
> -        dma-names = "tx", "rx";
> -        dmas = <&dma 26>, <&dma 27>;
> -        ...
> -};
> diff --git a/Documentation/devicetree/bindings/dma/owl-dma.yaml b/Documentation/devicetree/bindings/dma/owl-dma.yaml
> new file mode 100644
> index 000000000000..82e7d261e967
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/owl-dma.yaml
> @@ -0,0 +1,76 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/dma/owl-dma.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Actions Semi Owl SoCs DMA controller
> +
> +description: |
> +  The OWL DMA is a general-purpose direct memory access controller capable of
> +  supporting 10 and 12 independent DMA channels for S700 and S900 SoCs
> +  respectively.
> +
> +maintainers:
> +  - Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> +
> +allOf:
> +  - $ref: "dma-controller.yaml#"
> +
> +properties:
> +  compatible:
> +    enum:
> +      - actions,s900-dma
> +      - actions,s700-dma
> +
> +  reg:
> +    description:
> +      DMA registers location and length.

Don't need a description. Just need: 

maxItems: 1

> +
> +  interrupts:
> +    description:
> +      controller supports 4 interrupts, which are freely assignable to the
> +      DMA channels.
> +    maxItems: 4
> +
> +  "#dma-cells":
> +    const: 1
> +
> +  dma-channels:
> +    description:
> +      Physical channels supported.

Already defined in dma-controller.yaml. You need to add any constraints.
2^32 channels okay?

> +
> +  dma-requests:
> +    description:
> +      Number of DMA request signals supported by the controller.

Same here.

> +
> +  clocks:
> +    description:
> +      Phandle and Specifier of the clock feeding the DMA controller.

How many?

> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - "#dma-cells"
> +  - dma-channels
> +  - dma-requests
> +  - clocks

Add:

unevaluatedProperties: false

> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    dma: dma-controller@e0260000 {
> +        compatible = "actions,s900-dma";
> +        reg = <0x0 0xe0260000 0x0 0x1000>;
> +        interrupts = <GIC_SPI 57 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 58 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 59 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
> +        #dma-cells = <1>;
> +        dma-channels = <12>;
> +        dma-requests = <46>;
> +        clocks = <&clock 22>;
> +    };
> +
> +...
> -- 
> 2.7.4
> 

Re: [PATCH v2 08/10] dt-bindings: mmc: owl: add compatible string actions, s700-mmc

[Rob Herring]

On Tue, 19 May 2020 23:49:26 +0530, Amit Singh Tomar wrote:
> The commit adds a new SoC specific compatible string "actions,s700-mmc"
> in combination with more generic string "actions,owl-mmc".
> 
> Placement order of these strings should abide by the principle of
> "from most specific to most general".
> 
> Signed-off-by: Amit Singh Tomar <amittomer25@gmail.com>
> ---
> 	* Newly added patch in v2.
> ---
>  Documentation/devicetree/bindings/mmc/owl-mmc.yaml | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 

Reviewed-by: Rob Herring <robh@kernel.org>