[PATCH v4 0/8] i2c: i2c-mlxbf.c: bug fixes and new feature support

[PATCH v4 0/8] i2c: i2c-mlxbf.c: bug fixes and new feature support

[Asmaa Mnebhi]

This is a series of patches fixing several bugs and implementing
new features.

Bug fixes:
1) Fix the frequency calculation
2) Fix incorrect base address passed during io write
3) prevent stack overflow in mlxbf_i2c_smbus_start_transaction()
4) Support lock mechanism to avoid race condition between entities
   using the i2c bus

Cleanup:
5) remove IRQF_ONESHOT flag as it is no longer needed.

Features:
6) Support multi slave functionality
7) Support BlueField-3 SoC
8) Update binding devicetree

What has changed from v3->v4:
- moved the patch related to updating the SPDX licence out of this series.
  This will be submitted as a separate patch later and will need approval
  from all contributors.
- fixed build error in the frequency calculation patch. The name
  of the frequency functions changed but that was not reflected
  when they were called.
- Fixed the prefix in $subject as "i2c: <driver>:"
- Use kernel multiline comment style in the "support lock mechanism" patch
- instead of calling mlxbf_i2c_smbus_master_unlock multiple times, use the
  "goto out_unlock" style.
- Added the devicetree reviewers

Asmaa Mnebhi (8):
  i2c: i2c-mlxbf.c: Fix frequency calculation
  i2c: i2c-mlxbf.c: remove IRQF_ONESHOT
  i2c: i2c-mlxbf.c: incorrect base address passed during io write
  i2c: i2c-mlxbf: prevent stack overflow in
    mlxbf_i2c_smbus_start_transaction()
  i2c: i2c-mlxbf.c: support lock mechanism
  i2c: i2c-mlxbf: add multi slave functionality
  i2c: i2c-mlxbf.c: support BlueField-3 SoC
  i2c: i2c-mlxbf.c: Update binding devicetree

 .../bindings/i2c/mellanox,i2c-mlxbf.yaml      |  49 +-
 MAINTAINERS                                   |   1 +
 drivers/i2c/busses/i2c-mlxbf.c                | 862 ++++++++++--------
 3 files changed, 522 insertions(+), 390 deletions(-)

-- 
2.30.1

[PATCH v4 8/8] i2c: i2c-mlxbf.c: Update binding devicetree

[Asmaa Mnebhi]

In the latest version of the i2c-mlxbf.c driver, the "Smbus block"
resource was broken down to 3 separate resources "Smbus timer",
"Smbus master" and "Smbus slave" to accommodate for BlueField-3
SoC registers' changes.

Reviewed-by: Khalil Blaiech <kblaiech@nvidia.com>
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
---
 .../bindings/i2c/mellanox,i2c-mlxbf.yaml      | 49 ++++++++++++++-----
 1 file changed, 37 insertions(+), 12 deletions(-)

diff --git a/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml b/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml
index 93198d5d43a6..12dbe7e7967e 100644
--- a/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml
+++ b/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml
@@ -8,6 +8,7 @@ title: Mellanox I2C SMBus on BlueField SoCs
 
 maintainers:
   - Khalil Blaiech <kblaiech@nvidia.com>
+  - Asmaa Mnebhi <asmaa@nvidia.com>
 
 allOf:
   - $ref: /schemas/i2c/i2c-controller.yaml#
@@ -17,14 +18,19 @@ properties:
     enum:
       - mellanox,i2c-mlxbf1
       - mellanox,i2c-mlxbf2
+      - mellanox,i2c-mlxbf3
 
   reg:
     minItems: 3
+    maxItems: 6
     items:
       - description: Smbus block registers
       - description: Cause master registers
       - description: Cause slave registers
       - description: Cause coalesce registers
+      - description: Smbus timer registers
+      - description: Smbus master registers
+      - description: Smbus slave registers
 
   interrupts:
     maxItems: 1
@@ -35,6 +41,13 @@ properties:
       bus frequency used to configure timing registers;
       The frequency is expressed in Hz. Default is 100000.
 
+  resource_version:
+    enum: [ 0, 1 ]
+    description:
+      Version of the device tree. resource_version = 0 when the driver uses
+      Smbus block resource. resource_version = 1 when the driver uses Smbus
+      timer, Smbus master and Smbus slave resources.
+
 required:
   - compatible
   - reg
@@ -42,18 +55,6 @@ required:
 
 unevaluatedProperties: false
 
-if:
-  properties:
-    compatible:
-      contains:
-        enum:
-          - mellanox,i2c-mlxbf1
-
-then:
-  properties:
-    reg:
-      maxItems: 3
-
 examples:
   - |
     i2c@2804000 {
@@ -61,8 +62,13 @@ examples:
         reg = <0x02804000 0x800>,
               <0x02801200 0x020>,
               <0x02801260 0x020>;
+              <0x00000001 0x1>;
+              <0x02804000 0x40>,
+              <0x02804200 0x200>,
+              <0x02804400 0x200>,
         interrupts = <57>;
         clock-frequency = <100000>;
+        resource_version = <1>;
     };
 
   - |
@@ -72,6 +78,25 @@ examples:
               <0x02808e00 0x020>,
               <0x02808e20 0x020>,
               <0x02808e40 0x010>;
+              <0x02808800 0x040>;
+              <0x02808a00 0x200>,
+              <0x02808c00 0x200>,
         interrupts = <57>;
         clock-frequency = <400000>;
+        resource_version = <1>;
+    };
+
+  - |
+    i2c@2808800 {
+        compatible = "mellanox,i2c-mlxbf3";
+        reg = <0x00000001 0x1>,
+              <0x13404400 0x020>,
+              <0x13404420 0x020>,
+              <0x13404440 0x010>;
+              <0x13404480 0x40>,
+              <0x13404200 0x200>,
+              <0x13404000 0x200>,
+        interrupts = <35>;
+        clock-frequency = <400000>;
+        resource_version = <1>;
     };
-- 
2.30.1

Re: [PATCH v4 8/8] i2c: i2c-mlxbf.c: Update binding devicetree

[Krzysztof Kozlowski]

On Mon, 19 Sep 2022 17:34:31 -0400, Asmaa Mnebhi wrote:
> In the latest version of the i2c-mlxbf.c driver, the "Smbus block"
> resource was broken down to 3 separate resources "Smbus timer",
> "Smbus master" and "Smbus slave" to accommodate for BlueField-3
> SoC registers' changes.
> 
> Reviewed-by: Khalil Blaiech <kblaiech@nvidia.com>
> Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
> ---
>  .../bindings/i2c/mellanox,i2c-mlxbf.yaml      | 49 ++++++++++++++-----
>  1 file changed, 37 insertions(+), 12 deletions(-)
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml: properties:reg: {'minItems': 3, 'maxItems': 6, 'items': [{'description': 'Smbus block registers'}, {'description': 'Cause master registers'}, {'description': 'Cause slave registers'}, {'description': 'Cause coalesce registers'}, {'description': 'Smbus timer registers'}, {'description': 'Smbus master registers'}, {'description': 'Smbus slave registers'}]} should not be valid under {'required': ['maxItems']}
	hint: "maxItems" is not needed with an "items" list
	from schema $id: http://devicetree.org/meta-schemas/items.yaml#
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.yaml: ignoring, error in schema: properties: reg
Error: Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.example.dts:26.19-20 syntax error
FATAL ERROR: Unable to parse input tree
make[1]: *** [scripts/Makefile.lib:384: Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.example.dtb] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [Makefile:1420: dt_binding_check] Error 2

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/patch/

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit.