[PATCH v5 00/10] i2c: npcm: Bug fixes timeout, spurious interrupts

[PATCH v5 00/10] i2c: npcm: Bug fixes timeout, spurious interrupts

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

This patchset includes the following fixes:

- Add dt-bindings description for NPCM845.
- Bug fix for timeout calculation.
- Better handling of spurious interrupts.
- Fix for event type in slave mode.
- Removal of own slave addresses [2:10].
- Support for next gen BMC (NPCM845).

The NPCM I2C driver is tested on NPCM750 and NPCM845 evaluation boards.

Addressed comments from:
 - Krzysztof Kozlowski : https://www.spinics.net/lists/linux-i2c/
   msg56795.html
 - Andy Shevchenko : https://lkml.org/lkml/2022/5/10/297
 - Wolfram Sang : https://lkml.org/lkml/2022/5/17/38
 - Andy Shevchenko : https://lkml.org/lkml/2022/5/10/306
 - Andy Shevchenko : https://lkml.org/lkml/2022/5/10/309

Changes since version 4:
 - Remove quotes around ref handle to nuvoton,sys-mgr in i2c binding
   document.
 - Keep the "longer line first" order.
 - Correct the SoB chain.
 - Modify the if statement in one line and add new line characters.
 - Modify the commit message format in the patch Remove own slave
   addresses 2:10. Correct the if statement in one line and shorten the
   debug messages.
 - Create a new patch to capitalize the one-line comment in the driver.

Changes since version 3:
 - Correct the const format in if condition in i2c binding document.
 - Add the oops message statement and register information in register
   access width patch.
 - Add the occurring rate of the i2c spurious interrupt issue and more
   details in driver's behavior to overcome this issue.
 - Address Andy's comments in the patch to support NPCM845.
 
Changes since version 2:
 - Keep old code as fallback, if getting nuvoton,sys-mgr property fails.
 - Fix the error reported by running 'make DT_CHECKER_FLAGS=-m 
   dt_binding_check'.
 - Make nuvoton,sys-mgr required for nuvoton,npcm845-i2c.
 - Correct the patch's subject about changing the way of getting GCR
   regmap and add the description about keeping old code as fallback
   if getting nuvoton,sys-mgr property fails.
 - Correct the patch title and description about removing the unused 
   variable clk_regmap.
 - Use the data field directly instead of the macros since macros are
   not constants anymore in this patch.
 
Changes since version 1:
 - Add nuvoton,sys-mgr property in NPCM devicetree.
 - Describe the commit message in imperative mood.
 - Modify the description in i2c binding document to cover NPCM series.
 - Add new property in i2c binding document.
 - Create a new patch for client address calculation.
 - Create a new patch for updating gcr property name.
 - Create a new patch for removing unused clock node.
 - Explain EOB in the commit description.
 - Create a new patch for correcting NPCM register access width.
 - Remove some comment since the corresponding logic no longer exists.
 - Remove fixes tag while the patch adds an additional feature.
 - Use devicetree data field to support NPCM845.

Tali Perry (6):
  i2c: npcm: Change the way of getting GCR regmap
  i2c: npcm: Remove unused variable clk_regmap
  i2c: npcm: Fix timeout calculation
  i2c: npcm: Add tx complete counter
  i2c: npcm: Handle spurious interrupts
  i2c: npcm: Remove own slave addresses 2:10

Tyrone Ting (4):
  dt-bindings: i2c: npcm: support NPCM845
  i2c: npcm: Correct register access width
  i2c: npcm: Support NPCM845
  i2c: npcm: Capitalize the one-line comment

 .../bindings/i2c/nuvoton,npcm7xx-i2c.yaml     |  25 +-
 drivers/i2c/busses/Kconfig                    |   8 +-
 drivers/i2c/busses/Makefile                   |   2 +-
 drivers/i2c/busses/i2c-npcm7xx.c              | 277 +++++++++++-------
 4 files changed, 194 insertions(+), 118 deletions(-)

-- 
2.17.1

[PATCH v5 00/10] i2c: npcm: Bug fixes timeout, spurious interrupts

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

This patchset includes the following fixes:

- Add dt-bindings description for NPCM845.
- Bug fix for timeout calculation.
- Better handling of spurious interrupts.
- Fix for event type in slave mode.
- Removal of own slave addresses [2:10].
- Support for next gen BMC (NPCM845).

The NPCM I2C driver is tested on NPCM750 and NPCM845 evaluation boards.

Addressed comments from:
 - Krzysztof Kozlowski : https://www.spinics.net/lists/linux-i2c/
   msg56795.html
 - Andy Shevchenko : https://lkml.org/lkml/2022/5/10/297
 - Wolfram Sang : https://lkml.org/lkml/2022/5/17/38
 - Andy Shevchenko : https://lkml.org/lkml/2022/5/10/306
 - Andy Shevchenko : https://lkml.org/lkml/2022/5/10/309

Changes since version 4:
 - Remove quotes around ref handle to nuvoton,sys-mgr in i2c binding
   document.
 - Keep the "longer line first" order.
 - Correct the SoB chain.
 - Modify the if statement in one line and add new line characters.
 - Modify the commit message format in the patch Remove own slave
   addresses 2:10. Correct the if statement in one line and shorten the
   debug messages.
 - Create a new patch to capitalize the one-line comment in the driver.

Changes since version 3:
 - Correct the const format in if condition in i2c binding document.
 - Add the oops message statement and register information in register
   access width patch.
 - Add the occurring rate of the i2c spurious interrupt issue and more
   details in driver's behavior to overcome this issue.
 - Address Andy's comments in the patch to support NPCM845.
 
Changes since version 2:
 - Keep old code as fallback, if getting nuvoton,sys-mgr property fails.
 - Fix the error reported by running 'make DT_CHECKER_FLAGS=-m 
   dt_binding_check'.
 - Make nuvoton,sys-mgr required for nuvoton,npcm845-i2c.
 - Correct the patch's subject about changing the way of getting GCR
   regmap and add the description about keeping old code as fallback
   if getting nuvoton,sys-mgr property fails.
 - Correct the patch title and description about removing the unused 
   variable clk_regmap.
 - Use the data field directly instead of the macros since macros are
   not constants anymore in this patch.
 
Changes since version 1:
 - Add nuvoton,sys-mgr property in NPCM devicetree.
 - Describe the commit message in imperative mood.
 - Modify the description in i2c binding document to cover NPCM series.
 - Add new property in i2c binding document.
 - Create a new patch for client address calculation.
 - Create a new patch for updating gcr property name.
 - Create a new patch for removing unused clock node.
 - Explain EOB in the commit description.
 - Create a new patch for correcting NPCM register access width.
 - Remove some comment since the corresponding logic no longer exists.
 - Remove fixes tag while the patch adds an additional feature.
 - Use devicetree data field to support NPCM845.

Tali Perry (6):
  i2c: npcm: Change the way of getting GCR regmap
  i2c: npcm: Remove unused variable clk_regmap
  i2c: npcm: Fix timeout calculation
  i2c: npcm: Add tx complete counter
  i2c: npcm: Handle spurious interrupts
  i2c: npcm: Remove own slave addresses 2:10

Tyrone Ting (4):
  dt-bindings: i2c: npcm: support NPCM845
  i2c: npcm: Correct register access width
  i2c: npcm: Support NPCM845
  i2c: npcm: Capitalize the one-line comment

 .../bindings/i2c/nuvoton,npcm7xx-i2c.yaml     |  25 +-
 drivers/i2c/busses/Kconfig                    |   8 +-
 drivers/i2c/busses/Makefile                   |   2 +-
 drivers/i2c/busses/i2c-npcm7xx.c              | 277 +++++++++++-------
 4 files changed, 194 insertions(+), 118 deletions(-)

-- 
2.17.1

[PATCH v5 01/10] dt-bindings: i2c: npcm: support NPCM845

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

Add compatible and nuvoton,sys-mgr description for NPCM i2c module.

Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/i2c/nuvoton,npcm7xx-i2c.yaml     | 25 +++++++++++++++----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml b/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml
index 128444942aec..09d2591e1fa3 100644
--- a/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml
+++ b/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml
@@ -7,17 +7,18 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
 title: nuvoton NPCM7XX I2C Controller Device Tree Bindings
 
 description: |
-  The NPCM750x includes sixteen I2C bus controllers. All Controllers support
-  both master and slave mode. Each controller can switch between master and slave
-  at run time (i.e. IPMB mode). Each controller has two 16 byte HW FIFO for TX and
-  RX.
+  I2C bus controllers of the NPCM series support both master and
+  slave mode. Each controller can switch between master and slave at run time
+  (i.e. IPMB mode). HW FIFO for TX and RX are supported.
 
 maintainers:
   - Tali Perry <tali.perry1@gmail.com>
 
 properties:
   compatible:
-    const: nuvoton,npcm750-i2c
+    enum:
+      - nuvoton,npcm750-i2c
+      - nuvoton,npcm845-i2c
 
   reg:
     maxItems: 1
@@ -36,6 +37,10 @@ properties:
     default: 100000
     enum: [100000, 400000, 1000000]
 
+  nuvoton,sys-mgr:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: The phandle of system manager register node.
+
 required:
   - compatible
   - reg
@@ -44,6 +49,15 @@ required:
 
 allOf:
   - $ref: /schemas/i2c/i2c-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: nuvoton,npcm845-i2c
+
+    then:
+      required:
+        - nuvoton,sys-mgr
 
 unevaluatedProperties: false
 
@@ -57,6 +71,7 @@ examples:
         clock-frequency = <100000>;
         interrupts = <GIC_SPI 64 IRQ_TYPE_LEVEL_HIGH>;
         compatible = "nuvoton,npcm750-i2c";
+        nuvoton,sys-mgr = <&gcr>;
     };
 
 ...
-- 
2.17.1

[PATCH v5 01/10] dt-bindings: i2c: npcm: support NPCM845

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

Add compatible and nuvoton,sys-mgr description for NPCM i2c module.

Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/i2c/nuvoton,npcm7xx-i2c.yaml     | 25 +++++++++++++++----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml b/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml
index 128444942aec..09d2591e1fa3 100644
--- a/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml
+++ b/Documentation/devicetree/bindings/i2c/nuvoton,npcm7xx-i2c.yaml
@@ -7,17 +7,18 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
 title: nuvoton NPCM7XX I2C Controller Device Tree Bindings
 
 description: |
-  The NPCM750x includes sixteen I2C bus controllers. All Controllers support
-  both master and slave mode. Each controller can switch between master and slave
-  at run time (i.e. IPMB mode). Each controller has two 16 byte HW FIFO for TX and
-  RX.
+  I2C bus controllers of the NPCM series support both master and
+  slave mode. Each controller can switch between master and slave at run time
+  (i.e. IPMB mode). HW FIFO for TX and RX are supported.
 
 maintainers:
   - Tali Perry <tali.perry1@gmail.com>
 
 properties:
   compatible:
-    const: nuvoton,npcm750-i2c
+    enum:
+      - nuvoton,npcm750-i2c
+      - nuvoton,npcm845-i2c
 
   reg:
     maxItems: 1
@@ -36,6 +37,10 @@ properties:
     default: 100000
     enum: [100000, 400000, 1000000]
 
+  nuvoton,sys-mgr:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: The phandle of system manager register node.
+
 required:
   - compatible
   - reg
@@ -44,6 +49,15 @@ required:
 
 allOf:
   - $ref: /schemas/i2c/i2c-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: nuvoton,npcm845-i2c
+
+    then:
+      required:
+        - nuvoton,sys-mgr
 
 unevaluatedProperties: false
 
@@ -57,6 +71,7 @@ examples:
         clock-frequency = <100000>;
         interrupts = <GIC_SPI 64 IRQ_TYPE_LEVEL_HIGH>;
         compatible = "nuvoton,npcm750-i2c";
+        nuvoton,sys-mgr = <&gcr>;
     };
 
 ...
-- 
2.17.1

Re: [PATCH v5 01/10] dt-bindings: i2c: npcm: support NPCM845

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:33PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> Add compatible and nuvoton,sys-mgr description for NPCM i2c module.
> 
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Reviewed-by: Rob Herring <robh@kernel.org>

Needs to wait until comments to patches 8+9 are addressed.


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Re: [PATCH v5 01/10] dt-bindings: i2c: npcm: support NPCM845

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:33PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> Add compatible and nuvoton,sys-mgr description for NPCM i2c module.
> 
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Reviewed-by: Rob Herring <robh@kernel.org>

Needs to wait until comments to patches 8+9 are addressed.


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Re: [PATCH v5 01/10] dt-bindings: i2c: npcm: support NPCM845

[Tyrone Ting]

Hi Wolfram:

Thank you for your help.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午2:03寫道：
>
> On Tue, May 17, 2022 at 06:11:33PM +0800, Tyrone Ting wrote:
> > From: Tyrone Ting <kfting@nuvoton.com>
> >
> > Add compatible and nuvoton,sys-mgr description for NPCM i2c module.
> >
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> > Reviewed-by: Rob Herring <robh@kernel.org>
>
> Needs to wait until comments to patches 8+9 are addressed.
>

Best Regards,
Tyrone

[PATCH v5 02/10] i2c: npcm: Change the way of getting GCR regmap

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

Change the way of getting NPCM system manager reigster (GCR)
and still maintain the old mechanism as a fallback if getting
nuvoton,sys-mgr fails while working with the legacy devicetree
file.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 71aad029425d..de4e5f2f3e5a 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2229,11 +2229,12 @@ static void npcm_i2c_init_debugfs(struct platform_device *pdev,
 
 static int npcm_i2c_probe_bus(struct platform_device *pdev)
 {
-	struct npcm_i2c *bus;
-	struct i2c_adapter *adap;
-	struct clk *i2c_clk;
+	struct device_node *np = pdev->dev.of_node;
 	static struct regmap *gcr_regmap;
 	static struct regmap *clk_regmap;
+	struct i2c_adapter *adap;
+	struct npcm_i2c *bus;
+	struct clk *i2c_clk;
 	int irq;
 	int ret;
 
@@ -2250,7 +2251,10 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 		return PTR_ERR(i2c_clk);
 	bus->apb_clk = clk_get_rate(i2c_clk);
 
-	gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+	gcr_regmap = syscon_regmap_lookup_by_phandle(np, "nuvoton,sys-mgr");
+	if (IS_ERR(gcr_regmap))
+		gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+
 	if (IS_ERR(gcr_regmap))
 		return PTR_ERR(gcr_regmap);
 	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
-- 
2.17.1

[PATCH v5 02/10] i2c: npcm: Change the way of getting GCR regmap

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

Change the way of getting NPCM system manager reigster (GCR)
and still maintain the old mechanism as a fallback if getting
nuvoton,sys-mgr fails while working with the legacy devicetree
file.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 71aad029425d..de4e5f2f3e5a 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2229,11 +2229,12 @@ static void npcm_i2c_init_debugfs(struct platform_device *pdev,
 
 static int npcm_i2c_probe_bus(struct platform_device *pdev)
 {
-	struct npcm_i2c *bus;
-	struct i2c_adapter *adap;
-	struct clk *i2c_clk;
+	struct device_node *np = pdev->dev.of_node;
 	static struct regmap *gcr_regmap;
 	static struct regmap *clk_regmap;
+	struct i2c_adapter *adap;
+	struct npcm_i2c *bus;
+	struct clk *i2c_clk;
 	int irq;
 	int ret;
 
@@ -2250,7 +2251,10 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 		return PTR_ERR(i2c_clk);
 	bus->apb_clk = clk_get_rate(i2c_clk);
 
-	gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+	gcr_regmap = syscon_regmap_lookup_by_phandle(np, "nuvoton,sys-mgr");
+	if (IS_ERR(gcr_regmap))
+		gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+
 	if (IS_ERR(gcr_regmap))
 		return PTR_ERR(gcr_regmap);
 	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
-- 
2.17.1

Re: [PATCH v5 02/10] i2c: npcm: Change the way of getting GCR regmap

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:34PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> Change the way of getting NPCM system manager reigster (GCR)
> and still maintain the old mechanism as a fallback if getting
> nuvoton,sys-mgr fails while working with the legacy devicetree
> file.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

Applied to for-next, thanks!

I dropped the Fixes tag, doesn't look like a bugfix to me.


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Re: [PATCH v5 02/10] i2c: npcm: Change the way of getting GCR regmap

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:34PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> Change the way of getting NPCM system manager reigster (GCR)
> and still maintain the old mechanism as a fallback if getting
> nuvoton,sys-mgr fails while working with the legacy devicetree
> file.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

Applied to for-next, thanks!

I dropped the Fixes tag, doesn't look like a bugfix to me.


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Re: [PATCH v5 02/10] i2c: npcm: Change the way of getting GCR regmap

[Tyrone Ting]

Hi Wolfram:

Got it and thank you for your review.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午1:51寫道：
>
> On Tue, May 17, 2022 at 06:11:34PM +0800, Tyrone Ting wrote:
> > From: Tali Perry <tali.perry1@gmail.com>
> >
> > Change the way of getting NPCM system manager reigster (GCR)
> > and still maintain the old mechanism as a fallback if getting
> > nuvoton,sys-mgr fails while working with the legacy devicetree
> > file.
> >
> > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> > Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> > Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
>
> Applied to for-next, thanks!
>
> I dropped the Fixes tag, doesn't look like a bugfix to me.
>

Best Regards,
Tyrone

[PATCH v5 03/10] i2c: npcm: Remove unused variable clk_regmap

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

Remove unused variable clk_regmap.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index de4e5f2f3e5a..550e4a4d1e01 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2231,7 +2231,6 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	static struct regmap *gcr_regmap;
-	static struct regmap *clk_regmap;
 	struct i2c_adapter *adap;
 	struct npcm_i2c *bus;
 	struct clk *i2c_clk;
@@ -2259,10 +2258,6 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 		return PTR_ERR(gcr_regmap);
 	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
 
-	clk_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-clk");
-	if (IS_ERR(clk_regmap))
-		return PTR_ERR(clk_regmap);
-
 	bus->reg = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(bus->reg))
 		return PTR_ERR(bus->reg);
-- 
2.17.1

[PATCH v5 03/10] i2c: npcm: Remove unused variable clk_regmap

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

Remove unused variable clk_regmap.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index de4e5f2f3e5a..550e4a4d1e01 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2231,7 +2231,6 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	static struct regmap *gcr_regmap;
-	static struct regmap *clk_regmap;
 	struct i2c_adapter *adap;
 	struct npcm_i2c *bus;
 	struct clk *i2c_clk;
@@ -2259,10 +2258,6 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 		return PTR_ERR(gcr_regmap);
 	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
 
-	clk_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-clk");
-	if (IS_ERR(clk_regmap))
-		return PTR_ERR(clk_regmap);
-
 	bus->reg = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(bus->reg))
 		return PTR_ERR(bus->reg);
-- 
2.17.1

Re: [PATCH v5 03/10] i2c: npcm: Remove unused variable clk_regmap

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:35PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> Remove unused variable clk_regmap.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>

Applied to for-next, thanks!

I dropped the Fixes tag, doesn't look like a bugfix to me.


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Re: [PATCH v5 03/10] i2c: npcm: Remove unused variable clk_regmap

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 493 bytes --]

On Tue, May 17, 2022 at 06:11:35PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> Remove unused variable clk_regmap.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>

Applied to for-next, thanks!

I dropped the Fixes tag, doesn't look like a bugfix to me.


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Re: [PATCH v5 03/10] i2c: npcm: Remove unused variable clk_regmap

[Tyrone Ting]

Hi Wolfram:

Thank you for your help and review.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午1:51寫道：
>
> On Tue, May 17, 2022 at 06:11:35PM +0800, Tyrone Ting wrote:
> > From: Tali Perry <tali.perry1@gmail.com>
> >
> > Remove unused variable clk_regmap.
> >
> > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> > Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> > Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
>
> Applied to for-next, thanks!
>
> I dropped the Fixes tag, doesn't look like a bugfix to me.
>

Best Regards,
Tyrone

[PATCH v5 04/10] i2c: npcm: Fix timeout calculation

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

Use adap.timeout for timeout calculation instead of hard-coded
value of 35ms.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reported-by: kernel test robot <lkp@intel.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 550e4a4d1e01..489b4c8ad0ee 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2047,7 +2047,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	u16 nwrite, nread;
 	u8 *write_data, *read_data;
 	u8 slave_addr;
-	int timeout;
+	unsigned long timeout;
 	int ret = 0;
 	bool read_block = false;
 	bool read_PEC = false;
@@ -2099,13 +2099,13 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	 * 9: bits per transaction (including the ack/nack)
 	 */
 	timeout_usec = (2 * 9 * USEC_PER_SEC / bus->bus_freq) * (2 + nread + nwrite);
-	timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
+	timeout = max_t(unsigned long, bus->adap.timeout, usecs_to_jiffies(timeout_usec));
 	if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
 		dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
 		return -EINVAL;
 	}
 
-	time_left = jiffies + msecs_to_jiffies(DEFAULT_STALL_COUNT) + 1;
+	time_left = jiffies + timeout + 1;
 	do {
 		/*
 		 * we must clear slave address immediately when the bus is not
@@ -2268,7 +2268,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 	adap = &bus->adap;
 	adap->owner = THIS_MODULE;
 	adap->retries = 3;
-	adap->timeout = HZ;
+	adap->timeout = msecs_to_jiffies(35);
 	adap->algo = &npcm_i2c_algo;
 	adap->quirks = &npcm_i2c_quirks;
 	adap->algo_data = bus;
-- 
2.17.1

[PATCH v5 04/10] i2c: npcm: Fix timeout calculation

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

Use adap.timeout for timeout calculation instead of hard-coded
value of 35ms.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reported-by: kernel test robot <lkp@intel.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 550e4a4d1e01..489b4c8ad0ee 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2047,7 +2047,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	u16 nwrite, nread;
 	u8 *write_data, *read_data;
 	u8 slave_addr;
-	int timeout;
+	unsigned long timeout;
 	int ret = 0;
 	bool read_block = false;
 	bool read_PEC = false;
@@ -2099,13 +2099,13 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	 * 9: bits per transaction (including the ack/nack)
 	 */
 	timeout_usec = (2 * 9 * USEC_PER_SEC / bus->bus_freq) * (2 + nread + nwrite);
-	timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
+	timeout = max_t(unsigned long, bus->adap.timeout, usecs_to_jiffies(timeout_usec));
 	if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
 		dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
 		return -EINVAL;
 	}
 
-	time_left = jiffies + msecs_to_jiffies(DEFAULT_STALL_COUNT) + 1;
+	time_left = jiffies + timeout + 1;
 	do {
 		/*
 		 * we must clear slave address immediately when the bus is not
@@ -2268,7 +2268,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 	adap = &bus->adap;
 	adap->owner = THIS_MODULE;
 	adap->retries = 3;
-	adap->timeout = HZ;
+	adap->timeout = msecs_to_jiffies(35);
 	adap->algo = &npcm_i2c_algo;
 	adap->quirks = &npcm_i2c_quirks;
 	adap->algo_data = bus;
-- 
2.17.1

Re: [PATCH v5 04/10] i2c: npcm: Fix timeout calculation

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 498 bytes --]

On Tue, May 17, 2022 at 06:11:36PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> Use adap.timeout for timeout calculation instead of hard-coded
> value of 35ms.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Applied to for-next, thanks!

I dropped the Reported-by tag, doesn't look like test robot found this
issue.


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Re: [PATCH v5 04/10] i2c: npcm: Fix timeout calculation

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 498 bytes --]

On Tue, May 17, 2022 at 06:11:36PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> Use adap.timeout for timeout calculation instead of hard-coded
> value of 35ms.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Applied to for-next, thanks!

I dropped the Reported-by tag, doesn't look like test robot found this
issue.


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Re: [PATCH v5 04/10] i2c: npcm: Fix timeout calculation

[Tyrone Ting]

Hi Wolfram:

Thank you for your review.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午1:52寫道：
>
> On Tue, May 17, 2022 at 06:11:36PM +0800, Tyrone Ting wrote:
> > From: Tali Perry <tali.perry1@gmail.com>
> >
> > Use adap.timeout for timeout calculation instead of hard-coded
> > value of 35ms.
> >
> > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> > Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
>
> Applied to for-next, thanks!
>
> I dropped the Reported-by tag, doesn't look like test robot found this
> issue.
>

Best Regards,
Tyrone

[PATCH v5 05/10] i2c: npcm: Add tx complete counter

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

tx_complete counter is used to indicate successful transaction
count.
Similar counters for failed tx were previously added.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 489b4c8ad0ee..36f8aa7ab106 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -314,6 +314,7 @@ struct npcm_i2c {
 	u64 rec_fail_cnt;
 	u64 nack_cnt;
 	u64 timeout_cnt;
+	u64 tx_complete_cnt;
 };
 
 static inline void npcm_i2c_select_bank(struct npcm_i2c *bus,
@@ -684,6 +685,8 @@ static void npcm_i2c_callback(struct npcm_i2c *bus,
 	switch (op_status) {
 	case I2C_MASTER_DONE_IND:
 		bus->cmd_err = bus->msgs_num;
+		if (bus->tx_complete_cnt < ULLONG_MAX)
+			bus->tx_complete_cnt++;
 		fallthrough;
 	case I2C_BLOCK_BYTES_ERR_IND:
 		/* Master tx finished and all transmit bytes were sent */
@@ -2223,6 +2226,7 @@ static void npcm_i2c_init_debugfs(struct platform_device *pdev,
 	debugfs_create_u64("rec_succ_cnt", 0444, d, &bus->rec_succ_cnt);
 	debugfs_create_u64("rec_fail_cnt", 0444, d, &bus->rec_fail_cnt);
 	debugfs_create_u64("timeout_cnt", 0444, d, &bus->timeout_cnt);
+	debugfs_create_u64("tx_complete_cnt", 0444, d, &bus->tx_complete_cnt);
 
 	bus->debugfs = d;
 }
-- 
2.17.1

[PATCH v5 05/10] i2c: npcm: Add tx complete counter

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

tx_complete counter is used to indicate successful transaction
count.
Similar counters for failed tx were previously added.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 489b4c8ad0ee..36f8aa7ab106 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -314,6 +314,7 @@ struct npcm_i2c {
 	u64 rec_fail_cnt;
 	u64 nack_cnt;
 	u64 timeout_cnt;
+	u64 tx_complete_cnt;
 };
 
 static inline void npcm_i2c_select_bank(struct npcm_i2c *bus,
@@ -684,6 +685,8 @@ static void npcm_i2c_callback(struct npcm_i2c *bus,
 	switch (op_status) {
 	case I2C_MASTER_DONE_IND:
 		bus->cmd_err = bus->msgs_num;
+		if (bus->tx_complete_cnt < ULLONG_MAX)
+			bus->tx_complete_cnt++;
 		fallthrough;
 	case I2C_BLOCK_BYTES_ERR_IND:
 		/* Master tx finished and all transmit bytes were sent */
@@ -2223,6 +2226,7 @@ static void npcm_i2c_init_debugfs(struct platform_device *pdev,
 	debugfs_create_u64("rec_succ_cnt", 0444, d, &bus->rec_succ_cnt);
 	debugfs_create_u64("rec_fail_cnt", 0444, d, &bus->rec_fail_cnt);
 	debugfs_create_u64("timeout_cnt", 0444, d, &bus->timeout_cnt);
+	debugfs_create_u64("tx_complete_cnt", 0444, d, &bus->tx_complete_cnt);
 
 	bus->debugfs = d;
 }
-- 
2.17.1

Re: [PATCH v5 05/10] i2c: npcm: Add tx complete counter

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 527 bytes --]

On Tue, May 17, 2022 at 06:11:37PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> tx_complete counter is used to indicate successful transaction
> count.
> Similar counters for failed tx were previously added.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Applied to for-next, thanks!

I dropped the Fixes tag, doesn't look like a bugfix to me.


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Re: [PATCH v5 05/10] i2c: npcm: Add tx complete counter

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 527 bytes --]

On Tue, May 17, 2022 at 06:11:37PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> tx_complete counter is used to indicate successful transaction
> count.
> Similar counters for failed tx were previously added.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Applied to for-next, thanks!

I dropped the Fixes tag, doesn't look like a bugfix to me.


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Re: [PATCH v5 05/10] i2c: npcm: Add tx complete counter

[Tyrone Ting]

Hi Wolfram:

Thank you for your help and review.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午1:52寫道：
>
> On Tue, May 17, 2022 at 06:11:37PM +0800, Tyrone Ting wrote:
> > From: Tali Perry <tali.perry1@gmail.com>
> >
> > tx_complete counter is used to indicate successful transaction
> > count.
> > Similar counters for failed tx were previously added.
> >
> > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> > Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
>
> Applied to for-next, thanks!
>
> I dropped the Fixes tag, doesn't look like a bugfix to me.
>

Best Regards,
Tyrone

[PATCH v5 06/10] i2c: npcm: Correct register access width

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

The SMBnCTL3 register is 8-bit wide and the 32-bit access was always
incorrect, but simply didn't cause a visible error on the 32-bit machine.

On the 64-bit machine, the kernel message reports that ESR value is
0x96000021. Checking Arm Architecture Reference Manual Armv8 suggests that
it's the alignment fault.

SMBnCTL3's address is 0xE.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 36f8aa7ab106..58d7175f0362 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -360,14 +360,14 @@ static int npcm_i2c_get_SCL(struct i2c_adapter *_adap)
 {
 	struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap);
 
-	return !!(I2CCTL3_SCL_LVL & ioread32(bus->reg + NPCM_I2CCTL3));
+	return !!(I2CCTL3_SCL_LVL & ioread8(bus->reg + NPCM_I2CCTL3));
 }
 
 static int npcm_i2c_get_SDA(struct i2c_adapter *_adap)
 {
 	struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap);
 
-	return !!(I2CCTL3_SDA_LVL & ioread32(bus->reg + NPCM_I2CCTL3));
+	return !!(I2CCTL3_SDA_LVL & ioread8(bus->reg + NPCM_I2CCTL3));
 }
 
 static inline u16 npcm_i2c_get_index(struct npcm_i2c *bus)
-- 
2.17.1

[PATCH v5 06/10] i2c: npcm: Correct register access width

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

The SMBnCTL3 register is 8-bit wide and the 32-bit access was always
incorrect, but simply didn't cause a visible error on the 32-bit machine.

On the 64-bit machine, the kernel message reports that ESR value is
0x96000021. Checking Arm Architecture Reference Manual Armv8 suggests that
it's the alignment fault.

SMBnCTL3's address is 0xE.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 36f8aa7ab106..58d7175f0362 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -360,14 +360,14 @@ static int npcm_i2c_get_SCL(struct i2c_adapter *_adap)
 {
 	struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap);
 
-	return !!(I2CCTL3_SCL_LVL & ioread32(bus->reg + NPCM_I2CCTL3));
+	return !!(I2CCTL3_SCL_LVL & ioread8(bus->reg + NPCM_I2CCTL3));
 }
 
 static int npcm_i2c_get_SDA(struct i2c_adapter *_adap)
 {
 	struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap);
 
-	return !!(I2CCTL3_SDA_LVL & ioread32(bus->reg + NPCM_I2CCTL3));
+	return !!(I2CCTL3_SDA_LVL & ioread8(bus->reg + NPCM_I2CCTL3));
 }
 
 static inline u16 npcm_i2c_get_index(struct npcm_i2c *bus)
-- 
2.17.1

Re: [PATCH v5 06/10] i2c: npcm: Correct register access width

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:38PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> The SMBnCTL3 register is 8-bit wide and the 32-bit access was always
> incorrect, but simply didn't cause a visible error on the 32-bit machine.
> 
> On the 64-bit machine, the kernel message reports that ESR value is
> 0x96000021. Checking Arm Architecture Reference Manual Armv8 suggests that
> it's the alignment fault.
> 
> SMBnCTL3's address is 0xE.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>

Applied to for-next, thanks!


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Re: [PATCH v5 06/10] i2c: npcm: Correct register access width

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:38PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> The SMBnCTL3 register is 8-bit wide and the 32-bit access was always
> incorrect, but simply didn't cause a visible error on the 32-bit machine.
> 
> On the 64-bit machine, the kernel message reports that ESR value is
> 0x96000021. Checking Arm Architecture Reference Manual Armv8 suggests that
> it's the alignment fault.
> 
> SMBnCTL3's address is 0xE.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>

Applied to for-next, thanks!


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Re: [PATCH v5 06/10] i2c: npcm: Correct register access width

[Tyrone Ting]

Hi Wolfram:

Thank you for your help.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午1:53寫道：
>
> On Tue, May 17, 2022 at 06:11:38PM +0800, Tyrone Ting wrote:
> > From: Tyrone Ting <kfting@nuvoton.com>
> >
> > The SMBnCTL3 register is 8-bit wide and the 32-bit access was always
> > incorrect, but simply didn't cause a visible error on the 32-bit machine.
> >
> > On the 64-bit machine, the kernel message reports that ESR value is
> > 0x96000021. Checking Arm Architecture Reference Manual Armv8 suggests that
> > it's the alignment fault.
> >
> > SMBnCTL3's address is 0xE.
> >
> > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
> > Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
>
> Applied to for-next, thanks!
>

Best Regards,
Tyrone

[PATCH v5 07/10] i2c: npcm: Handle spurious interrupts

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

On some platforms in rare cases (1 to 100,000 transactions),
the i2c gets a spurious interrupt which means that we enter an interrupt
but in the interrupt handler we don't find any status bit that points to
the reason we got this interrupt.

This may be a case of a rare HW issue or signal integrity issue that is
still under investigation.

In order to overcome this we are doing the following:
1. Disable incoming interrupts in master mode only when slave mode is not
   enabled.
2. Clear end of busy (EOB) after every interrupt.
3. Clear other status bits (just in case since we found them cleared)
4. Return correct status during the interrupt that will finish the
   transaction.

On next xmit transaction if the bus is still busy the master will issue a
recovery process before issuing the new transaction.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 91 ++++++++++++++++++++++----------
 1 file changed, 62 insertions(+), 29 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 58d7175f0362..5960ccde6574 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -564,6 +564,15 @@ static inline void npcm_i2c_nack(struct npcm_i2c *bus)
 	iowrite8(val, bus->reg + NPCM_I2CCTL1);
 }
 
+static inline void npcm_i2c_clear_master_status(struct npcm_i2c *bus)
+{
+	u8 val;
+
+	/* Clear NEGACK, STASTR and BER bits */
+	val = NPCM_I2CST_BER | NPCM_I2CST_NEGACK | NPCM_I2CST_STASTR;
+	iowrite8(val, bus->reg + NPCM_I2CST);
+}
+
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 static void npcm_i2c_slave_int_enable(struct npcm_i2c *bus, bool enable)
 {
@@ -643,8 +652,8 @@ static void npcm_i2c_reset(struct npcm_i2c *bus)
 	iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST);
 	iowrite8(0xFF, bus->reg + NPCM_I2CST);
 
-	/* Clear EOB bit */
-	iowrite8(NPCM_I2CCST3_EO_BUSY, bus->reg + NPCM_I2CCST3);
+	/* Clear and disable EOB */
+	npcm_i2c_eob_int(bus, false);
 
 	/* Clear all fifo bits: */
 	iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, bus->reg + NPCM_I2CFIF_CTS);
@@ -656,6 +665,9 @@ static void npcm_i2c_reset(struct npcm_i2c *bus)
 	}
 #endif
 
+	/* clear status bits for spurious interrupts */
+	npcm_i2c_clear_master_status(bus);
+
 	bus->state = I2C_IDLE;
 }
 
@@ -818,15 +830,6 @@ static void npcm_i2c_read_fifo(struct npcm_i2c *bus, u8 bytes_in_fifo)
 	}
 }
 
-static inline void npcm_i2c_clear_master_status(struct npcm_i2c *bus)
-{
-	u8 val;
-
-	/* Clear NEGACK, STASTR and BER bits */
-	val = NPCM_I2CST_BER | NPCM_I2CST_NEGACK | NPCM_I2CST_STASTR;
-	iowrite8(val, bus->reg + NPCM_I2CST);
-}
-
 static void npcm_i2c_master_abort(struct npcm_i2c *bus)
 {
 	/* Only current master is allowed to issue a stop condition */
@@ -1234,7 +1237,16 @@ static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus)
 		ret = IRQ_HANDLED;
 	} /* SDAST */
 
-	return ret;
+	/*
+	 * if irq is not one of the above, make sure EOB is disabled and all
+	 * status bits are cleared.
+	 */
+	if (ret == IRQ_NONE) {
+		npcm_i2c_eob_int(bus, false);
+		npcm_i2c_clear_master_status(bus);
+	}
+
+	return IRQ_HANDLED;
 }
 
 static int npcm_i2c_reg_slave(struct i2c_client *client)
@@ -1470,6 +1482,9 @@ static void npcm_i2c_irq_handle_nack(struct npcm_i2c *bus)
 		npcm_i2c_eob_int(bus, false);
 		npcm_i2c_master_stop(bus);
 
+		/* Clear SDA Status bit (by reading dummy byte) */
+		npcm_i2c_rd_byte(bus);
+
 		/*
 		 * The bus is released from stall only after the SW clears
 		 * NEGACK bit. Then a Stop condition is sent.
@@ -1477,6 +1492,8 @@ static void npcm_i2c_irq_handle_nack(struct npcm_i2c *bus)
 		npcm_i2c_clear_master_status(bus);
 		readx_poll_timeout_atomic(ioread8, bus->reg + NPCM_I2CCST, val,
 					  !(val & NPCM_I2CCST_BUSY), 10, 200);
+		/* verify no status bits are still set after bus is released */
+		npcm_i2c_clear_master_status(bus);
 	}
 	bus->state = I2C_IDLE;
 
@@ -1675,10 +1692,10 @@ static int npcm_i2c_recovery_tgclk(struct i2c_adapter *_adap)
 	int              iter = 27;
 
 	if ((npcm_i2c_get_SDA(_adap) == 1) && (npcm_i2c_get_SCL(_adap) == 1)) {
-		dev_dbg(bus->dev, "bus%d recovery skipped, bus not stuck",
-			bus->num);
+		dev_dbg(bus->dev, "bus%d-0x%x recovery skipped, bus not stuck",
+			bus->num, bus->dest_addr);
 		npcm_i2c_reset(bus);
-		return status;
+		return 0;
 	}
 
 	npcm_i2c_int_enable(bus, false);
@@ -1912,6 +1929,7 @@ static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode,
 	    bus_freq_hz < I2C_FREQ_MIN_HZ || bus_freq_hz > I2C_FREQ_MAX_HZ)
 		return -EINVAL;
 
+	npcm_i2c_int_enable(bus, false);
 	npcm_i2c_disable(bus);
 
 	/* Configure FIFO mode : */
@@ -1940,10 +1958,17 @@ static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode,
 	val = (val | NPCM_I2CCTL1_NMINTE) & ~NPCM_I2CCTL1_RWS;
 	iowrite8(val, bus->reg + NPCM_I2CCTL1);
 
-	npcm_i2c_int_enable(bus, true);
-
 	npcm_i2c_reset(bus);
 
+	/* check HW is OK: SDA and SCL should be high at this point. */
+	if ((npcm_i2c_get_SDA(&bus->adap) == 0) || (npcm_i2c_get_SCL(&bus->adap) == 0)) {
+		dev_err(bus->dev, "I2C%d init fail: lines are low\n", bus->num);
+		dev_err(bus->dev, "SDA=%d SCL=%d\n", npcm_i2c_get_SDA(&bus->adap),
+			npcm_i2c_get_SCL(&bus->adap));
+		return -ENXIO;
+	}
+
+	npcm_i2c_int_enable(bus, true);
 	return 0;
 }
 
@@ -1991,10 +2016,14 @@ static irqreturn_t npcm_i2c_bus_irq(int irq, void *dev_id)
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 	if (bus->slave) {
 		bus->master_or_slave = I2C_SLAVE;
-		return npcm_i2c_int_slave_handler(bus);
+		if (npcm_i2c_int_slave_handler(bus))
+			return IRQ_HANDLED;
 	}
 #endif
-	return IRQ_NONE;
+	/* clear status bits for spurious interrupts */
+	npcm_i2c_clear_master_status(bus);
+
+	return IRQ_HANDLED;
 }
 
 static bool npcm_i2c_master_start_xmit(struct npcm_i2c *bus,
@@ -2051,7 +2080,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	u8 *write_data, *read_data;
 	u8 slave_addr;
 	unsigned long timeout;
-	int ret = 0;
 	bool read_block = false;
 	bool read_PEC = false;
 	u8 bus_busy;
@@ -2141,12 +2169,12 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	bus->read_block_use = read_block;
 
 	reinit_completion(&bus->cmd_complete);
-	if (!npcm_i2c_master_start_xmit(bus, slave_addr, nwrite, nread,
-					write_data, read_data, read_PEC,
-					read_block))
-		ret = -EBUSY;
 
-	if (ret != -EBUSY) {
+	npcm_i2c_int_enable(bus, true);
+
+	if (npcm_i2c_master_start_xmit(bus, slave_addr, nwrite, nread,
+				       write_data, read_data, read_PEC,
+				       read_block)) {
 		time_left = wait_for_completion_timeout(&bus->cmd_complete,
 							timeout);
 
@@ -2160,26 +2188,31 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 			}
 		}
 	}
-	ret = bus->cmd_err;
 
 	/* if there was BER, check if need to recover the bus: */
 	if (bus->cmd_err == -EAGAIN)
-		ret = i2c_recover_bus(adap);
+		bus->cmd_err = i2c_recover_bus(adap);
 
 	/*
 	 * After any type of error, check if LAST bit is still set,
 	 * due to a HW issue.
 	 * It cannot be cleared without resetting the module.
 	 */
-	if (bus->cmd_err &&
-	    (NPCM_I2CRXF_CTL_LAST_PEC & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
+	else if (bus->cmd_err &&
+		 (NPCM_I2CRXF_CTL_LAST_PEC & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
 		npcm_i2c_reset(bus);
 
+	/* after any xfer, successful or not, stall and EOB must be disabled */
+	npcm_i2c_stall_after_start(bus, false);
+	npcm_i2c_eob_int(bus, false);
+
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 	/* reenable slave if it was enabled */
 	if (bus->slave)
 		iowrite8((bus->slave->addr & 0x7F) | NPCM_I2CADDR_SAEN,
 			 bus->reg + NPCM_I2CADDR1);
+#else
+	npcm_i2c_int_enable(bus, false);
 #endif
 	return bus->cmd_err;
 }
-- 
2.17.1

[PATCH v5 07/10] i2c: npcm: Handle spurious interrupts

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

On some platforms in rare cases (1 to 100,000 transactions),
the i2c gets a spurious interrupt which means that we enter an interrupt
but in the interrupt handler we don't find any status bit that points to
the reason we got this interrupt.

This may be a case of a rare HW issue or signal integrity issue that is
still under investigation.

In order to overcome this we are doing the following:
1. Disable incoming interrupts in master mode only when slave mode is not
   enabled.
2. Clear end of busy (EOB) after every interrupt.
3. Clear other status bits (just in case since we found them cleared)
4. Return correct status during the interrupt that will finish the
   transaction.

On next xmit transaction if the bus is still busy the master will issue a
recovery process before issuing the new transaction.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 91 ++++++++++++++++++++++----------
 1 file changed, 62 insertions(+), 29 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 58d7175f0362..5960ccde6574 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -564,6 +564,15 @@ static inline void npcm_i2c_nack(struct npcm_i2c *bus)
 	iowrite8(val, bus->reg + NPCM_I2CCTL1);
 }
 
+static inline void npcm_i2c_clear_master_status(struct npcm_i2c *bus)
+{
+	u8 val;
+
+	/* Clear NEGACK, STASTR and BER bits */
+	val = NPCM_I2CST_BER | NPCM_I2CST_NEGACK | NPCM_I2CST_STASTR;
+	iowrite8(val, bus->reg + NPCM_I2CST);
+}
+
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 static void npcm_i2c_slave_int_enable(struct npcm_i2c *bus, bool enable)
 {
@@ -643,8 +652,8 @@ static void npcm_i2c_reset(struct npcm_i2c *bus)
 	iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST);
 	iowrite8(0xFF, bus->reg + NPCM_I2CST);
 
-	/* Clear EOB bit */
-	iowrite8(NPCM_I2CCST3_EO_BUSY, bus->reg + NPCM_I2CCST3);
+	/* Clear and disable EOB */
+	npcm_i2c_eob_int(bus, false);
 
 	/* Clear all fifo bits: */
 	iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, bus->reg + NPCM_I2CFIF_CTS);
@@ -656,6 +665,9 @@ static void npcm_i2c_reset(struct npcm_i2c *bus)
 	}
 #endif
 
+	/* clear status bits for spurious interrupts */
+	npcm_i2c_clear_master_status(bus);
+
 	bus->state = I2C_IDLE;
 }
 
@@ -818,15 +830,6 @@ static void npcm_i2c_read_fifo(struct npcm_i2c *bus, u8 bytes_in_fifo)
 	}
 }
 
-static inline void npcm_i2c_clear_master_status(struct npcm_i2c *bus)
-{
-	u8 val;
-
-	/* Clear NEGACK, STASTR and BER bits */
-	val = NPCM_I2CST_BER | NPCM_I2CST_NEGACK | NPCM_I2CST_STASTR;
-	iowrite8(val, bus->reg + NPCM_I2CST);
-}
-
 static void npcm_i2c_master_abort(struct npcm_i2c *bus)
 {
 	/* Only current master is allowed to issue a stop condition */
@@ -1234,7 +1237,16 @@ static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus)
 		ret = IRQ_HANDLED;
 	} /* SDAST */
 
-	return ret;
+	/*
+	 * if irq is not one of the above, make sure EOB is disabled and all
+	 * status bits are cleared.
+	 */
+	if (ret == IRQ_NONE) {
+		npcm_i2c_eob_int(bus, false);
+		npcm_i2c_clear_master_status(bus);
+	}
+
+	return IRQ_HANDLED;
 }
 
 static int npcm_i2c_reg_slave(struct i2c_client *client)
@@ -1470,6 +1482,9 @@ static void npcm_i2c_irq_handle_nack(struct npcm_i2c *bus)
 		npcm_i2c_eob_int(bus, false);
 		npcm_i2c_master_stop(bus);
 
+		/* Clear SDA Status bit (by reading dummy byte) */
+		npcm_i2c_rd_byte(bus);
+
 		/*
 		 * The bus is released from stall only after the SW clears
 		 * NEGACK bit. Then a Stop condition is sent.
@@ -1477,6 +1492,8 @@ static void npcm_i2c_irq_handle_nack(struct npcm_i2c *bus)
 		npcm_i2c_clear_master_status(bus);
 		readx_poll_timeout_atomic(ioread8, bus->reg + NPCM_I2CCST, val,
 					  !(val & NPCM_I2CCST_BUSY), 10, 200);
+		/* verify no status bits are still set after bus is released */
+		npcm_i2c_clear_master_status(bus);
 	}
 	bus->state = I2C_IDLE;
 
@@ -1675,10 +1692,10 @@ static int npcm_i2c_recovery_tgclk(struct i2c_adapter *_adap)
 	int              iter = 27;
 
 	if ((npcm_i2c_get_SDA(_adap) == 1) && (npcm_i2c_get_SCL(_adap) == 1)) {
-		dev_dbg(bus->dev, "bus%d recovery skipped, bus not stuck",
-			bus->num);
+		dev_dbg(bus->dev, "bus%d-0x%x recovery skipped, bus not stuck",
+			bus->num, bus->dest_addr);
 		npcm_i2c_reset(bus);
-		return status;
+		return 0;
 	}
 
 	npcm_i2c_int_enable(bus, false);
@@ -1912,6 +1929,7 @@ static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode,
 	    bus_freq_hz < I2C_FREQ_MIN_HZ || bus_freq_hz > I2C_FREQ_MAX_HZ)
 		return -EINVAL;
 
+	npcm_i2c_int_enable(bus, false);
 	npcm_i2c_disable(bus);
 
 	/* Configure FIFO mode : */
@@ -1940,10 +1958,17 @@ static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode,
 	val = (val | NPCM_I2CCTL1_NMINTE) & ~NPCM_I2CCTL1_RWS;
 	iowrite8(val, bus->reg + NPCM_I2CCTL1);
 
-	npcm_i2c_int_enable(bus, true);
-
 	npcm_i2c_reset(bus);
 
+	/* check HW is OK: SDA and SCL should be high at this point. */
+	if ((npcm_i2c_get_SDA(&bus->adap) == 0) || (npcm_i2c_get_SCL(&bus->adap) == 0)) {
+		dev_err(bus->dev, "I2C%d init fail: lines are low\n", bus->num);
+		dev_err(bus->dev, "SDA=%d SCL=%d\n", npcm_i2c_get_SDA(&bus->adap),
+			npcm_i2c_get_SCL(&bus->adap));
+		return -ENXIO;
+	}
+
+	npcm_i2c_int_enable(bus, true);
 	return 0;
 }
 
@@ -1991,10 +2016,14 @@ static irqreturn_t npcm_i2c_bus_irq(int irq, void *dev_id)
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 	if (bus->slave) {
 		bus->master_or_slave = I2C_SLAVE;
-		return npcm_i2c_int_slave_handler(bus);
+		if (npcm_i2c_int_slave_handler(bus))
+			return IRQ_HANDLED;
 	}
 #endif
-	return IRQ_NONE;
+	/* clear status bits for spurious interrupts */
+	npcm_i2c_clear_master_status(bus);
+
+	return IRQ_HANDLED;
 }
 
 static bool npcm_i2c_master_start_xmit(struct npcm_i2c *bus,
@@ -2051,7 +2080,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	u8 *write_data, *read_data;
 	u8 slave_addr;
 	unsigned long timeout;
-	int ret = 0;
 	bool read_block = false;
 	bool read_PEC = false;
 	u8 bus_busy;
@@ -2141,12 +2169,12 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	bus->read_block_use = read_block;
 
 	reinit_completion(&bus->cmd_complete);
-	if (!npcm_i2c_master_start_xmit(bus, slave_addr, nwrite, nread,
-					write_data, read_data, read_PEC,
-					read_block))
-		ret = -EBUSY;
 
-	if (ret != -EBUSY) {
+	npcm_i2c_int_enable(bus, true);
+
+	if (npcm_i2c_master_start_xmit(bus, slave_addr, nwrite, nread,
+				       write_data, read_data, read_PEC,
+				       read_block)) {
 		time_left = wait_for_completion_timeout(&bus->cmd_complete,
 							timeout);
 
@@ -2160,26 +2188,31 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 			}
 		}
 	}
-	ret = bus->cmd_err;
 
 	/* if there was BER, check if need to recover the bus: */
 	if (bus->cmd_err == -EAGAIN)
-		ret = i2c_recover_bus(adap);
+		bus->cmd_err = i2c_recover_bus(adap);
 
 	/*
 	 * After any type of error, check if LAST bit is still set,
 	 * due to a HW issue.
 	 * It cannot be cleared without resetting the module.
 	 */
-	if (bus->cmd_err &&
-	    (NPCM_I2CRXF_CTL_LAST_PEC & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
+	else if (bus->cmd_err &&
+		 (NPCM_I2CRXF_CTL_LAST_PEC & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
 		npcm_i2c_reset(bus);
 
+	/* after any xfer, successful or not, stall and EOB must be disabled */
+	npcm_i2c_stall_after_start(bus, false);
+	npcm_i2c_eob_int(bus, false);
+
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 	/* reenable slave if it was enabled */
 	if (bus->slave)
 		iowrite8((bus->slave->addr & 0x7F) | NPCM_I2CADDR_SAEN,
 			 bus->reg + NPCM_I2CADDR1);
+#else
+	npcm_i2c_int_enable(bus, false);
 #endif
 	return bus->cmd_err;
 }
-- 
2.17.1

Re: [PATCH v5 07/10] i2c: npcm: Handle spurious interrupts

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 1199 bytes --]

On Tue, May 17, 2022 at 06:11:39PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> On some platforms in rare cases (1 to 100,000 transactions),
> the i2c gets a spurious interrupt which means that we enter an interrupt
> but in the interrupt handler we don't find any status bit that points to
> the reason we got this interrupt.
> 
> This may be a case of a rare HW issue or signal integrity issue that is
> still under investigation.
> 
> In order to overcome this we are doing the following:
> 1. Disable incoming interrupts in master mode only when slave mode is not
>    enabled.
> 2. Clear end of busy (EOB) after every interrupt.
> 3. Clear other status bits (just in case since we found them cleared)
> 4. Return correct status during the interrupt that will finish the
>    transaction.
> 
> On next xmit transaction if the bus is still busy the master will issue a
> recovery process before issuing the new transaction.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Applied to for-next, thanks!


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Re: [PATCH v5 07/10] i2c: npcm: Handle spurious interrupts

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 1199 bytes --]

On Tue, May 17, 2022 at 06:11:39PM +0800, Tyrone Ting wrote:
> From: Tali Perry <tali.perry1@gmail.com>
> 
> On some platforms in rare cases (1 to 100,000 transactions),
> the i2c gets a spurious interrupt which means that we enter an interrupt
> but in the interrupt handler we don't find any status bit that points to
> the reason we got this interrupt.
> 
> This may be a case of a rare HW issue or signal integrity issue that is
> still under investigation.
> 
> In order to overcome this we are doing the following:
> 1. Disable incoming interrupts in master mode only when slave mode is not
>    enabled.
> 2. Clear end of busy (EOB) after every interrupt.
> 3. Clear other status bits (just in case since we found them cleared)
> 4. Return correct status during the interrupt that will finish the
>    transaction.
> 
> On next xmit transaction if the bus is still busy the master will issue a
> recovery process before issuing the new transaction.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Applied to for-next, thanks!


[-- Attachment #2: signature.asc --]
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Re: [PATCH v5 07/10] i2c: npcm: Handle spurious interrupts

[Tyrone Ting]

Hi Wolfram:

Thank you for your review.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午1:53寫道：
>
> On Tue, May 17, 2022 at 06:11:39PM +0800, Tyrone Ting wrote:
> > From: Tali Perry <tali.perry1@gmail.com>
> >
> > On some platforms in rare cases (1 to 100,000 transactions),
> > the i2c gets a spurious interrupt which means that we enter an interrupt
> > but in the interrupt handler we don't find any status bit that points to
> > the reason we got this interrupt.
> >
> > This may be a case of a rare HW issue or signal integrity issue that is
> > still under investigation.
> >
> > In order to overcome this we are doing the following:
> > 1. Disable incoming interrupts in master mode only when slave mode is not
> >    enabled.
> > 2. Clear end of busy (EOB) after every interrupt.
> > 3. Clear other status bits (just in case since we found them cleared)
> > 4. Return correct status during the interrupt that will finish the
> >    transaction.
> >
> > On next xmit transaction if the bus is still busy the master will issue a
> > recovery process before issuing the new transaction.
> >
> > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> > Signed-off-by: Tali Perry <tali.perry1@gmail.com>
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
>
> Applied to for-next, thanks!
>

Best Regards,
Tyrone

[PATCH v5 08/10] i2c: npcm: Remove own slave addresses 2:10

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

NPCM can support up to 10 own slave addresses. In practice, only one
address is actually being used. In order to access addresses 2 and above,
need to switch register banks. The switch needs spinlock.
To avoid using spinlock for this useless feature removed support of SA >=
2. Also fix returned slave event enum.

Remove some comment since the bank selection is not required. The bank
selection is not required since the supported slave addresses are reduced.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 43 +++++++++++++++-----------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 5960ccde6574..3f86895f5e64 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -124,6 +124,8 @@ enum i2c_addr {
  * use this array to get the address or each register.
  */
 #define I2C_NUM_OWN_ADDR 10
+#define I2C_NUM_OWN_ADDR_SUPPORTED 2
+
 static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 	NPCM_I2CADDR1, NPCM_I2CADDR2, NPCM_I2CADDR3, NPCM_I2CADDR4,
 	NPCM_I2CADDR5, NPCM_I2CADDR6, NPCM_I2CADDR7, NPCM_I2CADDR8,
@@ -392,14 +394,10 @@ static void npcm_i2c_disable(struct npcm_i2c *bus)
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 	int i;
 
-	/* select bank 0 for I2C addresses */
-	npcm_i2c_select_bank(bus, I2C_BANK_0);
-
 	/* Slave addresses removal */
-	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR; i++)
+	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR_SUPPORTED; i++)
 		iowrite8(0, bus->reg + npcm_i2caddr[i]);
 
-	npcm_i2c_select_bank(bus, I2C_BANK_1);
 #endif
 	/* Disable module */
 	i2cctl2 = ioread8(bus->reg + NPCM_I2CCTL2);
@@ -604,8 +602,7 @@ static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type,
 			i2cctl1 &= ~NPCM_I2CCTL1_GCMEN;
 		iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1);
 		return 0;
-	}
-	if (addr_type == I2C_ARP_ADDR) {
+	} else if (addr_type == I2C_ARP_ADDR) {
 		i2cctl3 = ioread8(bus->reg + NPCM_I2CCTL3);
 		if (enable)
 			i2cctl3 |= I2CCTL3_ARPMEN;
@@ -614,16 +611,17 @@ static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type,
 		iowrite8(i2cctl3, bus->reg + NPCM_I2CCTL3);
 		return 0;
 	}
+	if (addr_type > I2C_SLAVE_ADDR2 && addr_type <= I2C_SLAVE_ADDR10)
+		dev_err(bus->dev, "try to enable more than 2 SA not supported\n");
+
 	if (addr_type >= I2C_ARP_ADDR)
 		return -EFAULT;
 	/* select bank 0 for address 3 to 10 */
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_0);
+
 	/* Set and enable the address */
 	iowrite8(sa_reg, bus->reg + npcm_i2caddr[addr_type]);
 	npcm_i2c_slave_int_enable(bus, enable);
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_1);
+
 	return 0;
 }
 #endif
@@ -846,15 +844,11 @@ static u8 npcm_i2c_get_slave_addr(struct npcm_i2c *bus, enum i2c_addr addr_type)
 {
 	u8 slave_add;
 
-	/* select bank 0 for address 3 to 10 */
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_0);
+	if (addr_type > I2C_SLAVE_ADDR2 && addr_type <= I2C_SLAVE_ADDR10)
+		dev_err(bus->dev, "get slave: try to use more than 2 SA not supported\n");
 
 	slave_add = ioread8(bus->reg + npcm_i2caddr[(int)addr_type]);
 
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_1);
-
 	return slave_add;
 }
 
@@ -864,12 +858,12 @@ static int npcm_i2c_remove_slave_addr(struct npcm_i2c *bus, u8 slave_add)
 
 	/* Set the enable bit */
 	slave_add |= 0x80;
-	npcm_i2c_select_bank(bus, I2C_BANK_0);
-	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR; i++) {
+
+	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR_SUPPORTED; i++) {
 		if (ioread8(bus->reg + npcm_i2caddr[i]) == slave_add)
 			iowrite8(0, bus->reg + npcm_i2caddr[i]);
 	}
-	npcm_i2c_select_bank(bus, I2C_BANK_1);
+
 	return 0;
 }
 
@@ -924,11 +918,15 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
 	for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
 		if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
 			break;
-		i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+		if (bus->state == I2C_SLAVE_MATCH) {
+			i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+			bus->state = I2C_OPER_STARTED;
+		} else {
+			i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
+		}
 		ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
 		bus->slv_wr_buf[ind] = value;
 		bus->slv_wr_size++;
-		i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
 	}
 	return I2C_HW_FIFO_SIZE - ret;
 }
@@ -976,7 +974,6 @@ static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite,
 	if (nwrite == 0)
 		return;
 
-	bus->state = I2C_OPER_STARTED;
 	bus->operation = I2C_WRITE_OPER;
 
 	/* get the next buffer */
-- 
2.17.1

[PATCH v5 08/10] i2c: npcm: Remove own slave addresses 2:10

[Tyrone Ting]

From: Tali Perry <tali.perry1@gmail.com>

NPCM can support up to 10 own slave addresses. In practice, only one
address is actually being used. In order to access addresses 2 and above,
need to switch register banks. The switch needs spinlock.
To avoid using spinlock for this useless feature removed support of SA >=
2. Also fix returned slave event enum.

Remove some comment since the bank selection is not required. The bank
selection is not required since the supported slave addresses are reduced.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@gmail.com>
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 43 +++++++++++++++-----------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 5960ccde6574..3f86895f5e64 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -124,6 +124,8 @@ enum i2c_addr {
  * use this array to get the address or each register.
  */
 #define I2C_NUM_OWN_ADDR 10
+#define I2C_NUM_OWN_ADDR_SUPPORTED 2
+
 static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 	NPCM_I2CADDR1, NPCM_I2CADDR2, NPCM_I2CADDR3, NPCM_I2CADDR4,
 	NPCM_I2CADDR5, NPCM_I2CADDR6, NPCM_I2CADDR7, NPCM_I2CADDR8,
@@ -392,14 +394,10 @@ static void npcm_i2c_disable(struct npcm_i2c *bus)
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
 	int i;
 
-	/* select bank 0 for I2C addresses */
-	npcm_i2c_select_bank(bus, I2C_BANK_0);
-
 	/* Slave addresses removal */
-	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR; i++)
+	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR_SUPPORTED; i++)
 		iowrite8(0, bus->reg + npcm_i2caddr[i]);
 
-	npcm_i2c_select_bank(bus, I2C_BANK_1);
 #endif
 	/* Disable module */
 	i2cctl2 = ioread8(bus->reg + NPCM_I2CCTL2);
@@ -604,8 +602,7 @@ static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type,
 			i2cctl1 &= ~NPCM_I2CCTL1_GCMEN;
 		iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1);
 		return 0;
-	}
-	if (addr_type == I2C_ARP_ADDR) {
+	} else if (addr_type == I2C_ARP_ADDR) {
 		i2cctl3 = ioread8(bus->reg + NPCM_I2CCTL3);
 		if (enable)
 			i2cctl3 |= I2CCTL3_ARPMEN;
@@ -614,16 +611,17 @@ static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type,
 		iowrite8(i2cctl3, bus->reg + NPCM_I2CCTL3);
 		return 0;
 	}
+	if (addr_type > I2C_SLAVE_ADDR2 && addr_type <= I2C_SLAVE_ADDR10)
+		dev_err(bus->dev, "try to enable more than 2 SA not supported\n");
+
 	if (addr_type >= I2C_ARP_ADDR)
 		return -EFAULT;
 	/* select bank 0 for address 3 to 10 */
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_0);
+
 	/* Set and enable the address */
 	iowrite8(sa_reg, bus->reg + npcm_i2caddr[addr_type]);
 	npcm_i2c_slave_int_enable(bus, enable);
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_1);
+
 	return 0;
 }
 #endif
@@ -846,15 +844,11 @@ static u8 npcm_i2c_get_slave_addr(struct npcm_i2c *bus, enum i2c_addr addr_type)
 {
 	u8 slave_add;
 
-	/* select bank 0 for address 3 to 10 */
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_0);
+	if (addr_type > I2C_SLAVE_ADDR2 && addr_type <= I2C_SLAVE_ADDR10)
+		dev_err(bus->dev, "get slave: try to use more than 2 SA not supported\n");
 
 	slave_add = ioread8(bus->reg + npcm_i2caddr[(int)addr_type]);
 
-	if (addr_type > I2C_SLAVE_ADDR2)
-		npcm_i2c_select_bank(bus, I2C_BANK_1);
-
 	return slave_add;
 }
 
@@ -864,12 +858,12 @@ static int npcm_i2c_remove_slave_addr(struct npcm_i2c *bus, u8 slave_add)
 
 	/* Set the enable bit */
 	slave_add |= 0x80;
-	npcm_i2c_select_bank(bus, I2C_BANK_0);
-	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR; i++) {
+
+	for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR_SUPPORTED; i++) {
 		if (ioread8(bus->reg + npcm_i2caddr[i]) == slave_add)
 			iowrite8(0, bus->reg + npcm_i2caddr[i]);
 	}
-	npcm_i2c_select_bank(bus, I2C_BANK_1);
+
 	return 0;
 }
 
@@ -924,11 +918,15 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
 	for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
 		if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
 			break;
-		i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+		if (bus->state == I2C_SLAVE_MATCH) {
+			i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
+			bus->state = I2C_OPER_STARTED;
+		} else {
+			i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
+		}
 		ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
 		bus->slv_wr_buf[ind] = value;
 		bus->slv_wr_size++;
-		i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
 	}
 	return I2C_HW_FIFO_SIZE - ret;
 }
@@ -976,7 +974,6 @@ static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite,
 	if (nwrite == 0)
 		return;
 
-	bus->state = I2C_OPER_STARTED;
 	bus->operation = I2C_WRITE_OPER;
 
 	/* get the next buffer */
-- 
2.17.1

Re: [PATCH v5 08/10] i2c: npcm: Remove own slave addresses 2:10

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 2079 bytes --]


> NPCM can support up to 10 own slave addresses. In practice, only one
> address is actually being used. In order to access addresses 2 and above,
> need to switch register banks. The switch needs spinlock.
> To avoid using spinlock for this useless feature removed support of SA >=
> 2. Also fix returned slave event enum.

Is the spinlock contention so high? The code paths do not really look
like hot paths to me. A bit sad to see this feature go.

>  static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
>  	NPCM_I2CADDR1, NPCM_I2CADDR2, NPCM_I2CADDR3, NPCM_I2CADDR4,
>  	NPCM_I2CADDR5, NPCM_I2CADDR6, NPCM_I2CADDR7, NPCM_I2CADDR8,

Why do we keep this array if we drop the support?

> @@ -604,8 +602,7 @@ static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type,
>  			i2cctl1 &= ~NPCM_I2CCTL1_GCMEN;
>  		iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1);
>  		return 0;
> -	}
> -	if (addr_type == I2C_ARP_ADDR) {
> +	} else if (addr_type == I2C_ARP_ADDR) {

I might be wrong but this looks like a seperate change?

> @@ -924,11 +918,15 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
>  	for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
>  		if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
>  			break;
> -		i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
> +		if (bus->state == I2C_SLAVE_MATCH) {
> +			i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
> +			bus->state = I2C_OPER_STARTED;
> +		} else {
> +			i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
> +		}
>  		ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
>  		bus->slv_wr_buf[ind] = value;
>  		bus->slv_wr_size++;
> -		i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
>  	}
>  	return I2C_HW_FIFO_SIZE - ret;
>  }
> @@ -976,7 +974,6 @@ static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite,
>  	if (nwrite == 0)
>  		return;
>  
> -	bus->state = I2C_OPER_STARTED;
>  	bus->operation = I2C_WRITE_OPER;

This is definately a seperate change!

All the best!

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Re: [PATCH v5 08/10] i2c: npcm: Remove own slave addresses 2:10

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 2079 bytes --]


> NPCM can support up to 10 own slave addresses. In practice, only one
> address is actually being used. In order to access addresses 2 and above,
> need to switch register banks. The switch needs spinlock.
> To avoid using spinlock for this useless feature removed support of SA >=
> 2. Also fix returned slave event enum.

Is the spinlock contention so high? The code paths do not really look
like hot paths to me. A bit sad to see this feature go.

>  static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
>  	NPCM_I2CADDR1, NPCM_I2CADDR2, NPCM_I2CADDR3, NPCM_I2CADDR4,
>  	NPCM_I2CADDR5, NPCM_I2CADDR6, NPCM_I2CADDR7, NPCM_I2CADDR8,

Why do we keep this array if we drop the support?

> @@ -604,8 +602,7 @@ static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type,
>  			i2cctl1 &= ~NPCM_I2CCTL1_GCMEN;
>  		iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1);
>  		return 0;
> -	}
> -	if (addr_type == I2C_ARP_ADDR) {
> +	} else if (addr_type == I2C_ARP_ADDR) {

I might be wrong but this looks like a seperate change?

> @@ -924,11 +918,15 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
>  	for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
>  		if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
>  			break;
> -		i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
> +		if (bus->state == I2C_SLAVE_MATCH) {
> +			i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
> +			bus->state = I2C_OPER_STARTED;
> +		} else {
> +			i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
> +		}
>  		ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
>  		bus->slv_wr_buf[ind] = value;
>  		bus->slv_wr_size++;
> -		i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
>  	}
>  	return I2C_HW_FIFO_SIZE - ret;
>  }
> @@ -976,7 +974,6 @@ static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite,
>  	if (nwrite == 0)
>  		return;
>  
> -	bus->state = I2C_OPER_STARTED;
>  	bus->operation = I2C_WRITE_OPER;

This is definately a seperate change!

All the best!

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Re: [PATCH v5 08/10] i2c: npcm: Remove own slave addresses 2:10

[Tali Perry]

> On Sat, May 21, 2022 at 8:58 AM Wolfram Sang <wsa@kernel.org> wrote:
>
> > NPCM can support up to 10 own slave addresses. In practice, only one
> > address is actually being used. In order to access addresses 2 and above,
> > need to switch register banks. The switch needs spinlock.
> > To avoid using spinlock for this useless feature removed support of SA >=
> > 2. Also fix returned slave event enum.
>
> Is the spinlock contention so high? The code paths do not really look
> like hot paths to me. A bit sad to see this feature go.
>

The module has two seperate banks, accessible with a bit change. The
first one is used
for most of the runtime operations. Second bank is used mostly during init.
Unfortunetly, the first two own slave addresses are in the first bank
and the other
8 are in the second bank.

Every time the module switchs from master to slave mode, those
registers are accessed.
In theory, a spinlock can be used to protect those registers.
In practice, none of our customers use the extra addresses.
In fact they only need one.

The driver also does not allow you to register more then one slave per bus,
so this HW feature was not fully available to begin with.

So when we encounter a deadlock with this spinlock we decided to get rid of this
unused feature and get both a stable fix for the issue + performance benefits.
We work closely with all our customers so we know that this HW
feature is useless to them.

> >  static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
> >       NPCM_I2CADDR1, NPCM_I2CADDR2, NPCM_I2CADDR3, NPCM_I2CADDR4,
> >       NPCM_I2CADDR5, NPCM_I2CADDR6, NPCM_I2CADDR7, NPCM_I2CADDR8,
>
> Why do we keep this array if we drop the support?
>
This array represents the HW so we left it as-is. But I agree it can
be shortened to one\two.

> > @@ -604,8 +602,7 @@ static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type,
> >                       i2cctl1 &= ~NPCM_I2CCTL1_GCMEN;
> >               iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1);
> >               return 0;
> > -     }
> > -     if (addr_type == I2C_ARP_ADDR) {
> > +     } else if (addr_type == I2C_ARP_ADDR) {
>

addr_type type can be one of several options.
The code was
if (addr_type is 1st option)
...
if (addr_type is 2st option)
...
etc.

Adding that else is more accurate, but ommiting this change works as well.

> I might be wrong but this looks like a seperate change?
>
> > @@ -924,11 +918,15 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
> >       for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
> >               if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
> >                       break;
> > -             i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
> > +             if (bus->state == I2C_SLAVE_MATCH) {
> > +                     i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
> > +                     bus->state = I2C_OPER_STARTED;
> > +             } else {
> > +                     i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
> > +             }
> >               ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
> >               bus->slv_wr_buf[ind] = value;
> >               bus->slv_wr_size++;
> > -             i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
> >       }
> >       return I2C_HW_FIFO_SIZE - ret;
> >  }
> > @@ -976,7 +974,6 @@ static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite,
> >       if (nwrite == 0)
> >               return;
> >
> > -     bus->state = I2C_OPER_STARTED;
> >       bus->operation = I2C_WRITE_OPER;
>
> This is definately a seperate change!
>

OK, we will move the last two to a separate patch. BTW, this change
appears in the title as well.

But now I'm not sure: if you already apply for-next patches [1:7], and
we change patch [8:10]
do we need to re-submit [1:7]?

> All the best!

Thanks, Wolfram, for your review!
Much appreciated

Tali

Re: [PATCH v5 08/10] i2c: npcm: Remove own slave addresses 2:10

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 1065 bytes --]

Hi Tali,

> So when we encounter a deadlock with this spinlock we decided to get rid of this
> unused feature and get both a stable fix for the issue + performance benefits.
> We work closely with all our customers so we know that this HW
> feature is useless to them.

Okay, fair enough. Thanks for the detailed explanation!

> > Why do we keep this array if we drop the support?
> >
> This array represents the HW so we left it as-is. But I agree it can
> be shortened to one\two.

Would be nice, I think.

> OK, we will move the last two to a separate patch. BTW, this change
> appears in the title as well.

Yes, but I still think it should be a seperate change.

> But now I'm not sure: if you already apply for-next patches [1:7], and
> we change patch [8:10]
> do we need to re-submit [1:7]?

Nope, they are already in linux-next. They seemed like good fixes even
without the support for the new SoC, so I applied them right away. I
hope this was okay.

> Thanks, Wolfram, for your review!
> Much appreciated

You are welcome :)

Happy hacking,

   Wolfram


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Re: [PATCH v5 08/10] i2c: npcm: Remove own slave addresses 2:10

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 1065 bytes --]

Hi Tali,

> So when we encounter a deadlock with this spinlock we decided to get rid of this
> unused feature and get both a stable fix for the issue + performance benefits.
> We work closely with all our customers so we know that this HW
> feature is useless to them.

Okay, fair enough. Thanks for the detailed explanation!

> > Why do we keep this array if we drop the support?
> >
> This array represents the HW so we left it as-is. But I agree it can
> be shortened to one\two.

Would be nice, I think.

> OK, we will move the last two to a separate patch. BTW, this change
> appears in the title as well.

Yes, but I still think it should be a seperate change.

> But now I'm not sure: if you already apply for-next patches [1:7], and
> we change patch [8:10]
> do we need to re-submit [1:7]?

Nope, they are already in linux-next. They seemed like good fixes even
without the support for the new SoC, so I applied them right away. I
hope this was okay.

> Thanks, Wolfram, for your review!
> Much appreciated

You are welcome :)

Happy hacking,

   Wolfram


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[PATCH v5 09/10] i2c: npcm: Support NPCM845

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

Add NPCM8XX I2C support.
The NPCM8XX uses a similar i2c module as NPCM7XX.
The internal HW FIFO is larger in NPCM8XX.

Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/Kconfig       |   8 +--
 drivers/i2c/busses/Makefile      |   2 +-
 drivers/i2c/busses/i2c-npcm7xx.c | 114 +++++++++++++++++++------------
 3 files changed, 76 insertions(+), 48 deletions(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index a1bae59208e3..b1d7069dd377 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -838,13 +838,13 @@ config I2C_NOMADIK
 	  I2C interface from ST-Ericsson's Nomadik and Ux500 architectures,
 	  as well as the STA2X11 PCIe I/O HUB.
 
-config I2C_NPCM7XX
+config I2C_NPCM
 	tristate "Nuvoton I2C Controller"
-	depends on ARCH_NPCM7XX || COMPILE_TEST
+	depends on ARCH_NPCM || COMPILE_TEST
 	help
 	  If you say yes to this option, support will be included for the
-	  Nuvoton I2C controller, which is available on the NPCM7xx BMC
-	  controller.
+	  Nuvoton I2C controller, which is available on the NPCM BMC
+	  controllers.
 	  Driver can also support slave mode (select I2C_SLAVE).
 
 config I2C_OCORES
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 479f60e4ee3d..b0a10e5d9ee9 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -84,7 +84,7 @@ obj-$(CONFIG_I2C_MT7621)	+= i2c-mt7621.o
 obj-$(CONFIG_I2C_MV64XXX)	+= i2c-mv64xxx.o
 obj-$(CONFIG_I2C_MXS)		+= i2c-mxs.o
 obj-$(CONFIG_I2C_NOMADIK)	+= i2c-nomadik.o
-obj-$(CONFIG_I2C_NPCM7XX)	+= i2c-npcm7xx.o
+obj-$(CONFIG_I2C_NPCM)		+= i2c-npcm7xx.o
 obj-$(CONFIG_I2C_OCORES)	+= i2c-ocores.o
 obj-$(CONFIG_I2C_OMAP)		+= i2c-omap.o
 obj-$(CONFIG_I2C_OWL)		+= i2c-owl.o
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 3f86895f5e64..a032b407f104 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -17,6 +17,7 @@
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 
@@ -91,7 +92,6 @@ enum i2c_addr {
 
 /* init register and default value required to enable module */
 #define NPCM_I2CSEGCTL			0xE4
-#define NPCM_I2CSEGCTL_INIT_VAL		0x0333F000
 
 /* Common regs */
 #define NPCM_I2CSDA			0x00
@@ -228,8 +228,7 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 #define NPCM_I2CFIF_CTS_CLR_FIFO	BIT(6)
 #define NPCM_I2CFIF_CTS_SLVRSTR		BIT(7)
 
-/* NPCM_I2CTXF_CTL reg fields */
-#define NPCM_I2CTXF_CTL_TX_THR		GENMASK(4, 0)
+/* NPCM_I2CTXF_CTL reg field */
 #define NPCM_I2CTXF_CTL_THR_TXIE	BIT(6)
 
 /* NPCM_I2CT_OUT reg fields */
@@ -238,22 +237,18 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 #define NPCM_I2CT_OUT_T_OUTST		BIT(7)
 
 /* NPCM_I2CTXF_STS reg fields */
-#define NPCM_I2CTXF_STS_TX_BYTES	GENMASK(4, 0)
 #define NPCM_I2CTXF_STS_TX_THST		BIT(6)
 
 /* NPCM_I2CRXF_STS reg fields */
-#define NPCM_I2CRXF_STS_RX_BYTES	GENMASK(4, 0)
 #define NPCM_I2CRXF_STS_RX_THST		BIT(6)
 
 /* NPCM_I2CFIF_CTL reg fields */
 #define NPCM_I2CFIF_CTL_FIFO_EN		BIT(4)
 
 /* NPCM_I2CRXF_CTL reg fields */
-#define NPCM_I2CRXF_CTL_RX_THR		GENMASK(4, 0)
-#define NPCM_I2CRXF_CTL_LAST_PEC	BIT(5)
 #define NPCM_I2CRXF_CTL_THR_RXIE	BIT(6)
 
-#define I2C_HW_FIFO_SIZE		16
+#define MAX_I2C_HW_FIFO_SIZE		32
 
 /* I2C_VER reg fields */
 #define I2C_VER_VERSION			GENMASK(6, 0)
@@ -270,11 +265,36 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 #define I2C_FREQ_MIN_HZ			10000
 #define I2C_FREQ_MAX_HZ			I2C_MAX_FAST_MODE_PLUS_FREQ
 
+struct npcm_i2c_data {
+	u8 fifo_size;
+	u32 segctl_init_val;
+	u8 txf_sts_tx_bytes;
+	u8 rxf_sts_rx_bytes;
+	u8 rxf_ctl_last_pec;
+};
+
+static const struct npcm_i2c_data npxm7xx_i2c_data = {
+	.fifo_size = 16,
+	.segctl_init_val = 0x0333F000,
+	.txf_sts_tx_bytes = GENMASK(4, 0),
+	.rxf_sts_rx_bytes = GENMASK(4, 0),
+	.rxf_ctl_last_pec = BIT(5),
+};
+
+static const struct npcm_i2c_data npxm8xx_i2c_data = {
+	.fifo_size = 32,
+	.segctl_init_val = 0x9333F000,
+	.txf_sts_tx_bytes = GENMASK(5, 0),
+	.rxf_sts_rx_bytes = GENMASK(5, 0),
+	.rxf_ctl_last_pec = BIT(7),
+};
+
 /* Status of one I2C module */
 struct npcm_i2c {
 	struct i2c_adapter adap;
 	struct device *dev;
 	unsigned char __iomem *reg;
+	const struct npcm_i2c_data *data;
 	spinlock_t lock;   /* IRQ synchronization */
 	struct completion cmd_complete;
 	int cmd_err;
@@ -307,8 +327,8 @@ struct npcm_i2c {
 	int slv_rd_ind;
 	int slv_wr_size;
 	int slv_wr_ind;
-	u8 slv_rd_buf[I2C_HW_FIFO_SIZE];
-	u8 slv_wr_buf[I2C_HW_FIFO_SIZE];
+	u8 slv_rd_buf[MAX_I2C_HW_FIFO_SIZE];
+	u8 slv_wr_buf[MAX_I2C_HW_FIFO_SIZE];
 #endif
 	struct dentry *debugfs; /* debugfs device directory */
 	u64 ber_cnt;
@@ -441,7 +461,7 @@ static inline bool npcm_i2c_tx_fifo_empty(struct npcm_i2c *bus)
 
 	tx_fifo_sts = ioread8(bus->reg + NPCM_I2CTXF_STS);
 	/* check if TX FIFO is not empty */
-	if ((tx_fifo_sts & NPCM_I2CTXF_STS_TX_BYTES) == 0)
+	if ((tx_fifo_sts & bus->data->txf_sts_tx_bytes) == 0)
 		return false;
 
 	/* check if TX FIFO status bit is set: */
@@ -454,7 +474,7 @@ static inline bool npcm_i2c_rx_fifo_full(struct npcm_i2c *bus)
 
 	rx_fifo_sts = ioread8(bus->reg + NPCM_I2CRXF_STS);
 	/* check if RX FIFO is not empty: */
-	if ((rx_fifo_sts & NPCM_I2CRXF_STS_RX_BYTES) == 0)
+	if ((rx_fifo_sts & bus->data->rxf_sts_rx_bytes) == 0)
 		return false;
 
 	/* check if rx fifo full status is set: */
@@ -742,11 +762,11 @@ static void npcm_i2c_callback(struct npcm_i2c *bus,
 static u8 npcm_i2c_fifo_usage(struct npcm_i2c *bus)
 {
 	if (bus->operation == I2C_WRITE_OPER)
-		return FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
-				 ioread8(bus->reg + NPCM_I2CTXF_STS));
+		return (bus->data->txf_sts_tx_bytes &
+			ioread8(bus->reg + NPCM_I2CTXF_STS));
 	if (bus->operation == I2C_READ_OPER)
-		return FIELD_GET(NPCM_I2CRXF_STS_RX_BYTES,
-				 ioread8(bus->reg + NPCM_I2CRXF_STS));
+		return (bus->data->rxf_sts_rx_bytes &
+			ioread8(bus->reg + NPCM_I2CRXF_STS));
 	return 0;
 }
 
@@ -758,13 +778,13 @@ static void npcm_i2c_write_to_fifo_master(struct npcm_i2c *bus, u16 max_bytes)
 	 * Fill the FIFO, while the FIFO is not full and there are more bytes
 	 * to write
 	 */
-	size_free_fifo = I2C_HW_FIFO_SIZE - npcm_i2c_fifo_usage(bus);
+	size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus);
 	while (max_bytes-- && size_free_fifo) {
 		if (bus->wr_ind < bus->wr_size)
 			npcm_i2c_wr_byte(bus, bus->wr_buf[bus->wr_ind++]);
 		else
 			npcm_i2c_wr_byte(bus, 0xFF);
-		size_free_fifo = I2C_HW_FIFO_SIZE - npcm_i2c_fifo_usage(bus);
+		size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus);
 	}
 }
 
@@ -785,11 +805,11 @@ static void npcm_i2c_set_fifo(struct npcm_i2c *bus, int nread, int nwrite)
 
 	/* configure RX FIFO */
 	if (nread > 0) {
-		rxf_ctl = min_t(int, nread, I2C_HW_FIFO_SIZE);
+		rxf_ctl = min_t(int, nread, bus->data->fifo_size);
 
 		/* set LAST bit. if LAST is set next FIFO packet is nacked */
-		if (nread <= I2C_HW_FIFO_SIZE)
-			rxf_ctl |= NPCM_I2CRXF_CTL_LAST_PEC;
+		if (nread <= bus->data->fifo_size)
+			rxf_ctl |= bus->data->rxf_ctl_last_pec;
 
 		/*
 		 * if we are about to read the first byte in blk rd mode,
@@ -807,9 +827,9 @@ static void npcm_i2c_set_fifo(struct npcm_i2c *bus, int nread, int nwrite)
 
 	/* configure TX FIFO */
 	if (nwrite > 0) {
-		if (nwrite > I2C_HW_FIFO_SIZE)
+		if (nwrite > bus->data->fifo_size)
 			/* data to send is more then FIFO size. */
-			iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CTXF_CTL);
+			iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CTXF_CTL);
 		else
 			iowrite8(nwrite, bus->reg + NPCM_I2CTXF_CTL);
 
@@ -876,13 +896,13 @@ static void npcm_i2c_write_fifo_slave(struct npcm_i2c *bus, u16 max_bytes)
 	npcm_i2c_clear_fifo_int(bus);
 	npcm_i2c_clear_tx_fifo(bus);
 	iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
-	while (max_bytes-- && I2C_HW_FIFO_SIZE != npcm_i2c_fifo_usage(bus)) {
+	while (max_bytes-- && bus->data->fifo_size != npcm_i2c_fifo_usage(bus)) {
 		if (bus->slv_wr_size <= 0)
 			break;
-		bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+		bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1);
 		npcm_i2c_wr_byte(bus, bus->slv_wr_buf[bus->slv_wr_ind]);
 		bus->slv_wr_ind++;
-		bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+		bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1);
 		bus->slv_wr_size--;
 	}
 }
@@ -897,7 +917,7 @@ static void npcm_i2c_read_fifo_slave(struct npcm_i2c *bus, u8 bytes_in_fifo)
 	while (bytes_in_fifo--) {
 		data = npcm_i2c_rd_byte(bus);
 
-		bus->slv_rd_ind = bus->slv_rd_ind % I2C_HW_FIFO_SIZE;
+		bus->slv_rd_ind = bus->slv_rd_ind & (bus->data->fifo_size - 1);
 		bus->slv_rd_buf[bus->slv_rd_ind] = data;
 		bus->slv_rd_ind++;
 
@@ -915,8 +935,8 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
 	int ret = bus->slv_wr_ind;
 
 	/* fill a cyclic buffer */
-	for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
-		if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
+	for (i = 0; i < bus->data->fifo_size; i++) {
+		if (bus->slv_wr_size >= bus->data->fifo_size)
 			break;
 		if (bus->state == I2C_SLAVE_MATCH) {
 			i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
@@ -924,11 +944,11 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
 		} else {
 			i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
 		}
-		ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
+		ind = (bus->slv_wr_ind + bus->slv_wr_size) & (bus->data->fifo_size - 1);
 		bus->slv_wr_buf[ind] = value;
 		bus->slv_wr_size++;
 	}
-	return I2C_HW_FIFO_SIZE - ret;
+	return bus->data->fifo_size - ret;
 }
 
 static void npcm_i2c_slave_send_rd_buf(struct npcm_i2c *bus)
@@ -963,7 +983,7 @@ static void npcm_i2c_slave_receive(struct npcm_i2c *bus, u16 nread,
 	bus->slv_rd_ind = 0;
 
 	iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
-	iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL);
+	iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL);
 	npcm_i2c_clear_tx_fifo(bus);
 	npcm_i2c_clear_rx_fifo(bus);
 }
@@ -996,12 +1016,12 @@ static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus)
 {
 	int left_in_fifo;
 
-	left_in_fifo = FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
-				 ioread8(bus->reg + NPCM_I2CTXF_STS));
+	left_in_fifo = bus->data->txf_sts_tx_bytes &
+			ioread8(bus->reg + NPCM_I2CTXF_STS);
 
 	/* fifo already full: */
-	if (left_in_fifo >= I2C_HW_FIFO_SIZE ||
-	    bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
+	if (left_in_fifo >= bus->data->fifo_size ||
+	    bus->slv_wr_size >= bus->data->fifo_size)
 		return;
 
 	/* update the wr fifo index back to the untransmitted bytes: */
@@ -1009,7 +1029,7 @@ static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus)
 	bus->slv_wr_size = bus->slv_wr_size + left_in_fifo;
 
 	if (bus->slv_wr_ind < 0)
-		bus->slv_wr_ind += I2C_HW_FIFO_SIZE;
+		bus->slv_wr_ind += bus->data->fifo_size;
 }
 
 static void npcm_i2c_slave_rd_wr(struct npcm_i2c *bus)
@@ -1155,7 +1175,7 @@ static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus)
 		npcm_i2c_clear_rx_fifo(bus);
 		npcm_i2c_clear_tx_fifo(bus);
 		iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
-		iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL);
+		iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL);
 		if (NPCM_I2CST_XMIT & i2cst) {
 			bus->operation = I2C_WRITE_OPER;
 		} else {
@@ -1316,8 +1336,8 @@ static void npcm_i2c_master_fifo_read(struct npcm_i2c *bus)
 	 * read == FIFO Size + C (where C < FIFO Size)then first read C bytes
 	 * and in the next int we read rest of the data.
 	 */
-	if (rcount < (2 * I2C_HW_FIFO_SIZE) && rcount > I2C_HW_FIFO_SIZE)
-		fifo_bytes = rcount - I2C_HW_FIFO_SIZE;
+	if (rcount < (2 * bus->data->fifo_size) && rcount > bus->data->fifo_size)
+		fifo_bytes = rcount - bus->data->fifo_size;
 
 	if (rcount <= fifo_bytes) {
 		/* last bytes are about to be read - end of tx */
@@ -2196,7 +2216,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	 * It cannot be cleared without resetting the module.
 	 */
 	else if (bus->cmd_err &&
-		 (NPCM_I2CRXF_CTL_LAST_PEC & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
+		 (bus->data->rxf_ctl_last_pec & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
 		npcm_i2c_reset(bus);
 
 	/* after any xfer, successful or not, stall and EOB must be disabled */
@@ -2265,6 +2285,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	static struct regmap *gcr_regmap;
+	struct device *dev = &pdev->dev;
 	struct i2c_adapter *adap;
 	struct npcm_i2c *bus;
 	struct clk *i2c_clk;
@@ -2277,6 +2298,12 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 
 	bus->dev = &pdev->dev;
 
+	bus->data = of_device_get_match_data(dev);
+	if (!bus->data) {
+		dev_err(dev, "OF data missing\n");
+		return -EINVAL;
+	}
+
 	bus->num = of_alias_get_id(pdev->dev.of_node, "i2c");
 	/* core clk must be acquired to calculate module timing settings */
 	i2c_clk = devm_clk_get(&pdev->dev, NULL);
@@ -2290,7 +2317,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 
 	if (IS_ERR(gcr_regmap))
 		return PTR_ERR(gcr_regmap);
-	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
+	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, bus->data->segctl_init_val);
 
 	bus->reg = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(bus->reg))
@@ -2352,7 +2379,8 @@ static int npcm_i2c_remove_bus(struct platform_device *pdev)
 }
 
 static const struct of_device_id npcm_i2c_bus_of_table[] = {
-	{ .compatible = "nuvoton,npcm750-i2c", },
+	{ .compatible = "nuvoton,npcm750-i2c", .data = &npxm7xx_i2c_data },
+	{ .compatible = "nuvoton,npcm845-i2c", .data = &npxm8xx_i2c_data },
 	{}
 };
 MODULE_DEVICE_TABLE(of, npcm_i2c_bus_of_table);
-- 
2.17.1

[PATCH v5 09/10] i2c: npcm: Support NPCM845

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

Add NPCM8XX I2C support.
The NPCM8XX uses a similar i2c module as NPCM7XX.
The internal HW FIFO is larger in NPCM8XX.

Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/Kconfig       |   8 +--
 drivers/i2c/busses/Makefile      |   2 +-
 drivers/i2c/busses/i2c-npcm7xx.c | 114 +++++++++++++++++++------------
 3 files changed, 76 insertions(+), 48 deletions(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index a1bae59208e3..b1d7069dd377 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -838,13 +838,13 @@ config I2C_NOMADIK
 	  I2C interface from ST-Ericsson's Nomadik and Ux500 architectures,
 	  as well as the STA2X11 PCIe I/O HUB.
 
-config I2C_NPCM7XX
+config I2C_NPCM
 	tristate "Nuvoton I2C Controller"
-	depends on ARCH_NPCM7XX || COMPILE_TEST
+	depends on ARCH_NPCM || COMPILE_TEST
 	help
 	  If you say yes to this option, support will be included for the
-	  Nuvoton I2C controller, which is available on the NPCM7xx BMC
-	  controller.
+	  Nuvoton I2C controller, which is available on the NPCM BMC
+	  controllers.
 	  Driver can also support slave mode (select I2C_SLAVE).
 
 config I2C_OCORES
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 479f60e4ee3d..b0a10e5d9ee9 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -84,7 +84,7 @@ obj-$(CONFIG_I2C_MT7621)	+= i2c-mt7621.o
 obj-$(CONFIG_I2C_MV64XXX)	+= i2c-mv64xxx.o
 obj-$(CONFIG_I2C_MXS)		+= i2c-mxs.o
 obj-$(CONFIG_I2C_NOMADIK)	+= i2c-nomadik.o
-obj-$(CONFIG_I2C_NPCM7XX)	+= i2c-npcm7xx.o
+obj-$(CONFIG_I2C_NPCM)		+= i2c-npcm7xx.o
 obj-$(CONFIG_I2C_OCORES)	+= i2c-ocores.o
 obj-$(CONFIG_I2C_OMAP)		+= i2c-omap.o
 obj-$(CONFIG_I2C_OWL)		+= i2c-owl.o
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 3f86895f5e64..a032b407f104 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -17,6 +17,7 @@
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 
@@ -91,7 +92,6 @@ enum i2c_addr {
 
 /* init register and default value required to enable module */
 #define NPCM_I2CSEGCTL			0xE4
-#define NPCM_I2CSEGCTL_INIT_VAL		0x0333F000
 
 /* Common regs */
 #define NPCM_I2CSDA			0x00
@@ -228,8 +228,7 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 #define NPCM_I2CFIF_CTS_CLR_FIFO	BIT(6)
 #define NPCM_I2CFIF_CTS_SLVRSTR		BIT(7)
 
-/* NPCM_I2CTXF_CTL reg fields */
-#define NPCM_I2CTXF_CTL_TX_THR		GENMASK(4, 0)
+/* NPCM_I2CTXF_CTL reg field */
 #define NPCM_I2CTXF_CTL_THR_TXIE	BIT(6)
 
 /* NPCM_I2CT_OUT reg fields */
@@ -238,22 +237,18 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 #define NPCM_I2CT_OUT_T_OUTST		BIT(7)
 
 /* NPCM_I2CTXF_STS reg fields */
-#define NPCM_I2CTXF_STS_TX_BYTES	GENMASK(4, 0)
 #define NPCM_I2CTXF_STS_TX_THST		BIT(6)
 
 /* NPCM_I2CRXF_STS reg fields */
-#define NPCM_I2CRXF_STS_RX_BYTES	GENMASK(4, 0)
 #define NPCM_I2CRXF_STS_RX_THST		BIT(6)
 
 /* NPCM_I2CFIF_CTL reg fields */
 #define NPCM_I2CFIF_CTL_FIFO_EN		BIT(4)
 
 /* NPCM_I2CRXF_CTL reg fields */
-#define NPCM_I2CRXF_CTL_RX_THR		GENMASK(4, 0)
-#define NPCM_I2CRXF_CTL_LAST_PEC	BIT(5)
 #define NPCM_I2CRXF_CTL_THR_RXIE	BIT(6)
 
-#define I2C_HW_FIFO_SIZE		16
+#define MAX_I2C_HW_FIFO_SIZE		32
 
 /* I2C_VER reg fields */
 #define I2C_VER_VERSION			GENMASK(6, 0)
@@ -270,11 +265,36 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
 #define I2C_FREQ_MIN_HZ			10000
 #define I2C_FREQ_MAX_HZ			I2C_MAX_FAST_MODE_PLUS_FREQ
 
+struct npcm_i2c_data {
+	u8 fifo_size;
+	u32 segctl_init_val;
+	u8 txf_sts_tx_bytes;
+	u8 rxf_sts_rx_bytes;
+	u8 rxf_ctl_last_pec;
+};
+
+static const struct npcm_i2c_data npxm7xx_i2c_data = {
+	.fifo_size = 16,
+	.segctl_init_val = 0x0333F000,
+	.txf_sts_tx_bytes = GENMASK(4, 0),
+	.rxf_sts_rx_bytes = GENMASK(4, 0),
+	.rxf_ctl_last_pec = BIT(5),
+};
+
+static const struct npcm_i2c_data npxm8xx_i2c_data = {
+	.fifo_size = 32,
+	.segctl_init_val = 0x9333F000,
+	.txf_sts_tx_bytes = GENMASK(5, 0),
+	.rxf_sts_rx_bytes = GENMASK(5, 0),
+	.rxf_ctl_last_pec = BIT(7),
+};
+
 /* Status of one I2C module */
 struct npcm_i2c {
 	struct i2c_adapter adap;
 	struct device *dev;
 	unsigned char __iomem *reg;
+	const struct npcm_i2c_data *data;
 	spinlock_t lock;   /* IRQ synchronization */
 	struct completion cmd_complete;
 	int cmd_err;
@@ -307,8 +327,8 @@ struct npcm_i2c {
 	int slv_rd_ind;
 	int slv_wr_size;
 	int slv_wr_ind;
-	u8 slv_rd_buf[I2C_HW_FIFO_SIZE];
-	u8 slv_wr_buf[I2C_HW_FIFO_SIZE];
+	u8 slv_rd_buf[MAX_I2C_HW_FIFO_SIZE];
+	u8 slv_wr_buf[MAX_I2C_HW_FIFO_SIZE];
 #endif
 	struct dentry *debugfs; /* debugfs device directory */
 	u64 ber_cnt;
@@ -441,7 +461,7 @@ static inline bool npcm_i2c_tx_fifo_empty(struct npcm_i2c *bus)
 
 	tx_fifo_sts = ioread8(bus->reg + NPCM_I2CTXF_STS);
 	/* check if TX FIFO is not empty */
-	if ((tx_fifo_sts & NPCM_I2CTXF_STS_TX_BYTES) == 0)
+	if ((tx_fifo_sts & bus->data->txf_sts_tx_bytes) == 0)
 		return false;
 
 	/* check if TX FIFO status bit is set: */
@@ -454,7 +474,7 @@ static inline bool npcm_i2c_rx_fifo_full(struct npcm_i2c *bus)
 
 	rx_fifo_sts = ioread8(bus->reg + NPCM_I2CRXF_STS);
 	/* check if RX FIFO is not empty: */
-	if ((rx_fifo_sts & NPCM_I2CRXF_STS_RX_BYTES) == 0)
+	if ((rx_fifo_sts & bus->data->rxf_sts_rx_bytes) == 0)
 		return false;
 
 	/* check if rx fifo full status is set: */
@@ -742,11 +762,11 @@ static void npcm_i2c_callback(struct npcm_i2c *bus,
 static u8 npcm_i2c_fifo_usage(struct npcm_i2c *bus)
 {
 	if (bus->operation == I2C_WRITE_OPER)
-		return FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
-				 ioread8(bus->reg + NPCM_I2CTXF_STS));
+		return (bus->data->txf_sts_tx_bytes &
+			ioread8(bus->reg + NPCM_I2CTXF_STS));
 	if (bus->operation == I2C_READ_OPER)
-		return FIELD_GET(NPCM_I2CRXF_STS_RX_BYTES,
-				 ioread8(bus->reg + NPCM_I2CRXF_STS));
+		return (bus->data->rxf_sts_rx_bytes &
+			ioread8(bus->reg + NPCM_I2CRXF_STS));
 	return 0;
 }
 
@@ -758,13 +778,13 @@ static void npcm_i2c_write_to_fifo_master(struct npcm_i2c *bus, u16 max_bytes)
 	 * Fill the FIFO, while the FIFO is not full and there are more bytes
 	 * to write
 	 */
-	size_free_fifo = I2C_HW_FIFO_SIZE - npcm_i2c_fifo_usage(bus);
+	size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus);
 	while (max_bytes-- && size_free_fifo) {
 		if (bus->wr_ind < bus->wr_size)
 			npcm_i2c_wr_byte(bus, bus->wr_buf[bus->wr_ind++]);
 		else
 			npcm_i2c_wr_byte(bus, 0xFF);
-		size_free_fifo = I2C_HW_FIFO_SIZE - npcm_i2c_fifo_usage(bus);
+		size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus);
 	}
 }
 
@@ -785,11 +805,11 @@ static void npcm_i2c_set_fifo(struct npcm_i2c *bus, int nread, int nwrite)
 
 	/* configure RX FIFO */
 	if (nread > 0) {
-		rxf_ctl = min_t(int, nread, I2C_HW_FIFO_SIZE);
+		rxf_ctl = min_t(int, nread, bus->data->fifo_size);
 
 		/* set LAST bit. if LAST is set next FIFO packet is nacked */
-		if (nread <= I2C_HW_FIFO_SIZE)
-			rxf_ctl |= NPCM_I2CRXF_CTL_LAST_PEC;
+		if (nread <= bus->data->fifo_size)
+			rxf_ctl |= bus->data->rxf_ctl_last_pec;
 
 		/*
 		 * if we are about to read the first byte in blk rd mode,
@@ -807,9 +827,9 @@ static void npcm_i2c_set_fifo(struct npcm_i2c *bus, int nread, int nwrite)
 
 	/* configure TX FIFO */
 	if (nwrite > 0) {
-		if (nwrite > I2C_HW_FIFO_SIZE)
+		if (nwrite > bus->data->fifo_size)
 			/* data to send is more then FIFO size. */
-			iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CTXF_CTL);
+			iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CTXF_CTL);
 		else
 			iowrite8(nwrite, bus->reg + NPCM_I2CTXF_CTL);
 
@@ -876,13 +896,13 @@ static void npcm_i2c_write_fifo_slave(struct npcm_i2c *bus, u16 max_bytes)
 	npcm_i2c_clear_fifo_int(bus);
 	npcm_i2c_clear_tx_fifo(bus);
 	iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
-	while (max_bytes-- && I2C_HW_FIFO_SIZE != npcm_i2c_fifo_usage(bus)) {
+	while (max_bytes-- && bus->data->fifo_size != npcm_i2c_fifo_usage(bus)) {
 		if (bus->slv_wr_size <= 0)
 			break;
-		bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+		bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1);
 		npcm_i2c_wr_byte(bus, bus->slv_wr_buf[bus->slv_wr_ind]);
 		bus->slv_wr_ind++;
-		bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+		bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1);
 		bus->slv_wr_size--;
 	}
 }
@@ -897,7 +917,7 @@ static void npcm_i2c_read_fifo_slave(struct npcm_i2c *bus, u8 bytes_in_fifo)
 	while (bytes_in_fifo--) {
 		data = npcm_i2c_rd_byte(bus);
 
-		bus->slv_rd_ind = bus->slv_rd_ind % I2C_HW_FIFO_SIZE;
+		bus->slv_rd_ind = bus->slv_rd_ind & (bus->data->fifo_size - 1);
 		bus->slv_rd_buf[bus->slv_rd_ind] = data;
 		bus->slv_rd_ind++;
 
@@ -915,8 +935,8 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
 	int ret = bus->slv_wr_ind;
 
 	/* fill a cyclic buffer */
-	for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
-		if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
+	for (i = 0; i < bus->data->fifo_size; i++) {
+		if (bus->slv_wr_size >= bus->data->fifo_size)
 			break;
 		if (bus->state == I2C_SLAVE_MATCH) {
 			i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
@@ -924,11 +944,11 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
 		} else {
 			i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
 		}
-		ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
+		ind = (bus->slv_wr_ind + bus->slv_wr_size) & (bus->data->fifo_size - 1);
 		bus->slv_wr_buf[ind] = value;
 		bus->slv_wr_size++;
 	}
-	return I2C_HW_FIFO_SIZE - ret;
+	return bus->data->fifo_size - ret;
 }
 
 static void npcm_i2c_slave_send_rd_buf(struct npcm_i2c *bus)
@@ -963,7 +983,7 @@ static void npcm_i2c_slave_receive(struct npcm_i2c *bus, u16 nread,
 	bus->slv_rd_ind = 0;
 
 	iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
-	iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL);
+	iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL);
 	npcm_i2c_clear_tx_fifo(bus);
 	npcm_i2c_clear_rx_fifo(bus);
 }
@@ -996,12 +1016,12 @@ static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus)
 {
 	int left_in_fifo;
 
-	left_in_fifo = FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
-				 ioread8(bus->reg + NPCM_I2CTXF_STS));
+	left_in_fifo = bus->data->txf_sts_tx_bytes &
+			ioread8(bus->reg + NPCM_I2CTXF_STS);
 
 	/* fifo already full: */
-	if (left_in_fifo >= I2C_HW_FIFO_SIZE ||
-	    bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
+	if (left_in_fifo >= bus->data->fifo_size ||
+	    bus->slv_wr_size >= bus->data->fifo_size)
 		return;
 
 	/* update the wr fifo index back to the untransmitted bytes: */
@@ -1009,7 +1029,7 @@ static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus)
 	bus->slv_wr_size = bus->slv_wr_size + left_in_fifo;
 
 	if (bus->slv_wr_ind < 0)
-		bus->slv_wr_ind += I2C_HW_FIFO_SIZE;
+		bus->slv_wr_ind += bus->data->fifo_size;
 }
 
 static void npcm_i2c_slave_rd_wr(struct npcm_i2c *bus)
@@ -1155,7 +1175,7 @@ static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus)
 		npcm_i2c_clear_rx_fifo(bus);
 		npcm_i2c_clear_tx_fifo(bus);
 		iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
-		iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL);
+		iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL);
 		if (NPCM_I2CST_XMIT & i2cst) {
 			bus->operation = I2C_WRITE_OPER;
 		} else {
@@ -1316,8 +1336,8 @@ static void npcm_i2c_master_fifo_read(struct npcm_i2c *bus)
 	 * read == FIFO Size + C (where C < FIFO Size)then first read C bytes
 	 * and in the next int we read rest of the data.
 	 */
-	if (rcount < (2 * I2C_HW_FIFO_SIZE) && rcount > I2C_HW_FIFO_SIZE)
-		fifo_bytes = rcount - I2C_HW_FIFO_SIZE;
+	if (rcount < (2 * bus->data->fifo_size) && rcount > bus->data->fifo_size)
+		fifo_bytes = rcount - bus->data->fifo_size;
 
 	if (rcount <= fifo_bytes) {
 		/* last bytes are about to be read - end of tx */
@@ -2196,7 +2216,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 	 * It cannot be cleared without resetting the module.
 	 */
 	else if (bus->cmd_err &&
-		 (NPCM_I2CRXF_CTL_LAST_PEC & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
+		 (bus->data->rxf_ctl_last_pec & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
 		npcm_i2c_reset(bus);
 
 	/* after any xfer, successful or not, stall and EOB must be disabled */
@@ -2265,6 +2285,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	static struct regmap *gcr_regmap;
+	struct device *dev = &pdev->dev;
 	struct i2c_adapter *adap;
 	struct npcm_i2c *bus;
 	struct clk *i2c_clk;
@@ -2277,6 +2298,12 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 
 	bus->dev = &pdev->dev;
 
+	bus->data = of_device_get_match_data(dev);
+	if (!bus->data) {
+		dev_err(dev, "OF data missing\n");
+		return -EINVAL;
+	}
+
 	bus->num = of_alias_get_id(pdev->dev.of_node, "i2c");
 	/* core clk must be acquired to calculate module timing settings */
 	i2c_clk = devm_clk_get(&pdev->dev, NULL);
@@ -2290,7 +2317,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
 
 	if (IS_ERR(gcr_regmap))
 		return PTR_ERR(gcr_regmap);
-	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
+	regmap_write(gcr_regmap, NPCM_I2CSEGCTL, bus->data->segctl_init_val);
 
 	bus->reg = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(bus->reg))
@@ -2352,7 +2379,8 @@ static int npcm_i2c_remove_bus(struct platform_device *pdev)
 }
 
 static const struct of_device_id npcm_i2c_bus_of_table[] = {
-	{ .compatible = "nuvoton,npcm750-i2c", },
+	{ .compatible = "nuvoton,npcm750-i2c", .data = &npxm7xx_i2c_data },
+	{ .compatible = "nuvoton,npcm845-i2c", .data = &npxm8xx_i2c_data },
 	{}
 };
 MODULE_DEVICE_TABLE(of, npcm_i2c_bus_of_table);
-- 
2.17.1

Re: [PATCH v5 09/10] i2c: npcm: Support NPCM845

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:41PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> Add NPCM8XX I2C support.
> The NPCM8XX uses a similar i2c module as NPCM7XX.
> The internal HW FIFO is larger in NPCM8XX.
> 
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Would be great to get an ack from one of the listed Nuvoton maintainers.


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Re: [PATCH v5 09/10] i2c: npcm: Support NPCM845

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:41PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> Add NPCM8XX I2C support.
> The NPCM8XX uses a similar i2c module as NPCM7XX.
> The internal HW FIFO is larger in NPCM8XX.
> 
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Would be great to get an ack from one of the listed Nuvoton maintainers.


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Re: [PATCH v5 09/10] i2c: npcm: Support NPCM845

[Tyrone Ting]

Hi Wolfram:

Thank you for your reminder.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午2:01寫道：

>
> On Tue, May 17, 2022 at 06:11:41PM +0800, Tyrone Ting wrote:
> > From: Tyrone Ting <kfting@nuvoton.com>
> >
> > Add NPCM8XX I2C support.
> > The NPCM8XX uses a similar i2c module as NPCM7XX.
> > The internal HW FIFO is larger in NPCM8XX.
> >
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
>
> Would be great to get an ack from one of the listed Nuvoton maintainers.
>

Best Regards,
Tyrone

Re: [PATCH v5 09/10] i2c: npcm: Support NPCM845

[Tomer Maimon]

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Hi Wolfram,

Appreciate your review!

On Sat, 21 May 2022 at 16:10, Tyrone Ting <warp5tw@gmail.com> wrote:

> Hi Wolfram:
>
> Thank you for your reminder.
>
> Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午2:01寫道：
>
> >
> > On Tue, May 17, 2022 at 06:11:41PM +0800, Tyrone Ting wrote:
> > > From: Tyrone Ting <kfting@nuvoton.com>
> > >
> > > Add NPCM8XX I2C support.
> > > The NPCM8XX uses a similar i2c module as NPCM7XX.
> > > The internal HW FIFO is larger in NPCM8XX.
> > >
> > > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
>
>
> > Would be great to get an ack from one of the listed Nuvoton maintainers.
> >
>
> Best Regards,
> Tyrone
>

Acked-by:  Tomer Maimon <tmaimon77@gmail.com>

Best Regards,

Tomer

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[PATCH v5 10/10] i2c: npcm: Capitalize the one-line comment

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

Make the one-line comments capital in the driver to get the comment style
consistent.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index a032b407f104..a60e392dda50 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -683,7 +683,7 @@ static void npcm_i2c_reset(struct npcm_i2c *bus)
 	}
 #endif
 
-	/* clear status bits for spurious interrupts */
+	/* Clear status bits for spurious interrupts */
 	npcm_i2c_clear_master_status(bus);
 
 	bus->state = I2C_IDLE;
@@ -1255,7 +1255,7 @@ static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus)
 	} /* SDAST */
 
 	/*
-	 * if irq is not one of the above, make sure EOB is disabled and all
+	 * If irq is not one of the above, make sure EOB is disabled and all
 	 * status bits are cleared.
 	 */
 	if (ret == IRQ_NONE) {
@@ -1509,7 +1509,7 @@ static void npcm_i2c_irq_handle_nack(struct npcm_i2c *bus)
 		npcm_i2c_clear_master_status(bus);
 		readx_poll_timeout_atomic(ioread8, bus->reg + NPCM_I2CCST, val,
 					  !(val & NPCM_I2CCST_BUSY), 10, 200);
-		/* verify no status bits are still set after bus is released */
+		/* Verify no status bits are still set after bus is released */
 		npcm_i2c_clear_master_status(bus);
 	}
 	bus->state = I2C_IDLE;
@@ -1977,7 +1977,7 @@ static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode,
 
 	npcm_i2c_reset(bus);
 
-	/* check HW is OK: SDA and SCL should be high at this point. */
+	/* Check HW is OK: SDA and SCL should be high at this point. */
 	if ((npcm_i2c_get_SDA(&bus->adap) == 0) || (npcm_i2c_get_SCL(&bus->adap) == 0)) {
 		dev_err(bus->dev, "I2C%d init fail: lines are low\n", bus->num);
 		dev_err(bus->dev, "SDA=%d SCL=%d\n", npcm_i2c_get_SDA(&bus->adap),
@@ -2037,7 +2037,7 @@ static irqreturn_t npcm_i2c_bus_irq(int irq, void *dev_id)
 			return IRQ_HANDLED;
 	}
 #endif
-	/* clear status bits for spurious interrupts */
+	/* Clear status bits for spurious interrupts */
 	npcm_i2c_clear_master_status(bus);
 
 	return IRQ_HANDLED;
@@ -2219,7 +2219,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 		 (bus->data->rxf_ctl_last_pec & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
 		npcm_i2c_reset(bus);
 
-	/* after any xfer, successful or not, stall and EOB must be disabled */
+	/* After any xfer, successful or not, stall and EOB must be disabled */
 	npcm_i2c_stall_after_start(bus, false);
 	npcm_i2c_eob_int(bus, false);
 
-- 
2.17.1

[PATCH v5 10/10] i2c: npcm: Capitalize the one-line comment

[Tyrone Ting]

From: Tyrone Ting <kfting@nuvoton.com>

Make the one-line comments capital in the driver to get the comment style
consistent.

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index a032b407f104..a60e392dda50 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -683,7 +683,7 @@ static void npcm_i2c_reset(struct npcm_i2c *bus)
 	}
 #endif
 
-	/* clear status bits for spurious interrupts */
+	/* Clear status bits for spurious interrupts */
 	npcm_i2c_clear_master_status(bus);
 
 	bus->state = I2C_IDLE;
@@ -1255,7 +1255,7 @@ static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus)
 	} /* SDAST */
 
 	/*
-	 * if irq is not one of the above, make sure EOB is disabled and all
+	 * If irq is not one of the above, make sure EOB is disabled and all
 	 * status bits are cleared.
 	 */
 	if (ret == IRQ_NONE) {
@@ -1509,7 +1509,7 @@ static void npcm_i2c_irq_handle_nack(struct npcm_i2c *bus)
 		npcm_i2c_clear_master_status(bus);
 		readx_poll_timeout_atomic(ioread8, bus->reg + NPCM_I2CCST, val,
 					  !(val & NPCM_I2CCST_BUSY), 10, 200);
-		/* verify no status bits are still set after bus is released */
+		/* Verify no status bits are still set after bus is released */
 		npcm_i2c_clear_master_status(bus);
 	}
 	bus->state = I2C_IDLE;
@@ -1977,7 +1977,7 @@ static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode,
 
 	npcm_i2c_reset(bus);
 
-	/* check HW is OK: SDA and SCL should be high at this point. */
+	/* Check HW is OK: SDA and SCL should be high at this point. */
 	if ((npcm_i2c_get_SDA(&bus->adap) == 0) || (npcm_i2c_get_SCL(&bus->adap) == 0)) {
 		dev_err(bus->dev, "I2C%d init fail: lines are low\n", bus->num);
 		dev_err(bus->dev, "SDA=%d SCL=%d\n", npcm_i2c_get_SDA(&bus->adap),
@@ -2037,7 +2037,7 @@ static irqreturn_t npcm_i2c_bus_irq(int irq, void *dev_id)
 			return IRQ_HANDLED;
 	}
 #endif
-	/* clear status bits for spurious interrupts */
+	/* Clear status bits for spurious interrupts */
 	npcm_i2c_clear_master_status(bus);
 
 	return IRQ_HANDLED;
@@ -2219,7 +2219,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 		 (bus->data->rxf_ctl_last_pec & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
 		npcm_i2c_reset(bus);
 
-	/* after any xfer, successful or not, stall and EOB must be disabled */
+	/* After any xfer, successful or not, stall and EOB must be disabled */
 	npcm_i2c_stall_after_start(bus, false);
 	npcm_i2c_eob_int(bus, false);
 
-- 
2.17.1

Re: [PATCH v5 10/10] i2c: npcm: Capitalize the one-line comment

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:42PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> Make the one-line comments capital in the driver to get the comment style
> consistent.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Needs to wait until comments to patches 8+9 are addressed.


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Re: [PATCH v5 10/10] i2c: npcm: Capitalize the one-line comment

[Wolfram Sang]

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On Tue, May 17, 2022 at 06:11:42PM +0800, Tyrone Ting wrote:
> From: Tyrone Ting <kfting@nuvoton.com>
> 
> Make the one-line comments capital in the driver to get the comment style
> consistent.
> 
> Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> Signed-off-by: Tyrone Ting <kfting@nuvoton.com>

Needs to wait until comments to patches 8+9 are addressed.


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Re: [PATCH v5 10/10] i2c: npcm: Capitalize the one-line comment

[Tyrone Ting]

Hi Wolfram:

Got it and thank you for your help.

Wolfram Sang <wsa@kernel.org> 於 2022年5月21日 週六 下午2:03寫道：
>
> On Tue, May 17, 2022 at 06:11:42PM +0800, Tyrone Ting wrote:
> > From: Tyrone Ting <kfting@nuvoton.com>
> >
> > Make the one-line comments capital in the driver to get the comment style
> > consistent.
> >
> > Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
> > Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
>
> Needs to wait until comments to patches 8+9 are addressed.
>

Best Regards,
Tyrone