-----Original Message-----
From: Rob Herring <robh@kernel.org>
Sent: Monday, December 27, 2021 9:46 AM
To: Jarrett Schultz <redacted>
Cc: Jarrett Schultz <redacted>; Andy Gross
[off-list ref]; bjorn.andersson@linaro.org; Hans de Goede
[off-list ref]; Mark Gross [off-list ref]; Maximilian
Luz [off-list ref]; Felipe Balbi [off-list ref]; linux-arm-
msm@vger.kernel.org; platform-driver-x86@vger.kernel.org; linux-
kernel@vger.kernel.org; devicetree@vger.kernel.org
Subject: Re: [EXTERNAL] Re: [PATCH RESEND v4 1/4] dt-bindings: platform:
microsoft: Document surface xbl

On Mon, Dec 27, 2021 at 10:54 AM Jarrett Schultz
[off-list ref] wrote:

quoted

quoted

-----Original Message-----
From: Rob Herring <robh@kernel.org>
Sent: Tuesday, December 21, 2021 5:24 PM
To: Jarrett Schultz <redacted>
Cc: Andy Gross <agross@kernel.org>; bjorn.andersson@linaro.org; Hans
de Goede [off-list ref]; Mark Gross

[off-list ref];

quoted

quoted

Maximilian Luz [off-list ref]; Felipe Balbi
[off-list ref]; linux-arm-msm@vger.kernel.org; platform-driver-
x86@vger.kernel.org; linux-kernel@vger.kernel.org;
devicetree@vger.kernel.org; Jarrett Schultz
[off-list ref]
Subject: [EXTERNAL] Re: [PATCH RESEND v4 1/4] dt-bindings: platform:
microsoft: Document surface xbl

On Tue, Dec 21, 2021 at 10:28:23AM -0800, Jarrett Schultz wrote:

quoted

From: Jarrett Schultz <redacted>

Introduce yaml for surface xbl driver.

Signed-off-by: Jarrett Schultz <redacted>

---

Changes in v4:
 - Addressed small formatting changes
 - Removed unnecessary lines

---

Changes in v3:
 - Updated description to only pertain to the hardware
 - Updated the required field to properly reflect the binding
 - Removed the first example
 - Fixed the size of the reg field in the second example

---

Changes in v2:
 - Removed json-schema dependence
 - Elaborated on description of driver
 - Updated example
---
 .../platform/microsoft/surface-xbl.yaml       | 64 +++++++++++++++++++
 MAINTAINERS                                   |  7 ++
 2 files changed, 71 insertions(+)  create mode 100644
Documentation/devicetree/bindings/platform/microsoft/surface-xbl.y
aml

diff --git
a/Documentation/devicetree/bindings/platform/microsoft/surface-

xbl.yam

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l
b/Documentation/devicetree/bindings/platform/microsoft/surface-

xbl.yam

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l
new file mode 100644
index 000000000000..df5a87a016f4

--- /dev/null
+++ b/Documentation/devicetree/bindings/platform/microsoft/surface
+++ -xbl
+++ .yaml

@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML
+1.2
+---
+$id:

+https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fde

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+vi

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+cetree.org%2Fschemas%2Fplatform%2Fmicrosoft%2Fsurface-

xbl.yaml%23&amp

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+;data=04%7C01%7Cjaschultz%40microsoft.com%7C77abe729b69a40624472

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08d9c

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+4d8f44e%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C637757258

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3887312

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+05%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luM

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zIiLCJBTi

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+I6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=jG0qubz122GG2s8%2B

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1ZuMCcPIa

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+33KWwPoO2VNlDySmvs%3D&reserved=0
+$schema:

+https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fde

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+vi

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+cetree.org%2Fmeta-

schemas%2Fcore.yaml%23&data=04%7C01%7Cjaschultz

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+%40microsoft.com%7C77abe729b69a4062447208d9c4d8f44e%7C72f988bf8

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6f141a

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+f91ab2d7cd011db47%7C0%7C0%7C637757258388731205%7CUnknown%7C

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TWFpbGZsb3

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+d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0

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%3D%

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+7C3000&sdata=FxKNLPok9eW%2FBPmuGzU6x7dPwpnev0Ngr8epO4NA

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UzA%3D&amp

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+;reserved=0
+
+title: Surface Extensible Bootloader for Microsoft Surface Duo
+
+maintainers:
+  - Jarrett Schultz [off-list ref]
+
+description: |
+  Defined to expose information that is used during production
+when
+  device is in manufacturing mode. Some of the information
+included
+  in this imem section is -

If this is onchip sram, we have a binding for that. That's not an MFD.

quoted

+    * board_id
+    * battery_present
+    * hw_init_retries
+    * is_customer_mode
+    * is_act_mode
+    * pmic_reset_reason
+    * touch_fw_version
+    * ocp_error_location

nvmem binding doesn't work for describing these fields?

quoted

+  See sysfs documentation for more information.

sysfs? Not relevant to the binding.

quoted

+
+properties:
+  compatible:
+    const: simple-mfd
+
+  reg:
+    maxItems: 1
+
+additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - ranges
+  - address-cells
+  - size-cells
+
+examples:
+  - |
+    / {
+        compatible = "foo";
+        model = "foo";

No need to make this the root node with a fake compatible.

I included this root node in order to make #address-cells =
#size-cells = 2, since this example raises errors otherwise.

Why does your example require 2 cells? You only have 4KB of address space.

The soc node that imem sits under in sm8150.dtsi defines it that way so for
continuity I figured that it would make sense for the example to mirror that.

Also, should imem and xbl be documented in separate files?

Though you can do:

bus {
  #address-cells = <2>;
  #size-cells = <2>;
  ...
};

Rob