mbox series

[v2,0/3] Add support for lan966x flexcom chip-select configuration

Message ID 20220607144740.14937-1-kavyasree.kotagiri@microchip.com
Headers show
Series Add support for lan966x flexcom chip-select configuration | expand

Message

Kavyasree Kotagiri June 7, 2022, 2:47 p.m. UTC
This patch series converts atmel-flexcom bindings into json-schema format.
Adds support for lan966x flexcom chip-select configurations and its
DT bindings.

v1 -> v2:
 - minor fix in title of dt-bindings.
 - Modified new dt properties usage in atmel,flexcom.yaml.
 - Used GENMASK and macros for maximum allowed values.
 - Use u32 values for flexcom chipselects instead of strings.
 - disable clock in case of errors.

Kavyasree Kotagiri (3):
  dt-bindings: mfd: atmel,flexcom: Convert to json-schema
  dt-bindings: mfd: atmel,flexcom: Add new compatible string for lan966x
  mfd: atmel-flexcom: Add support for lan966x flexcom chip-select
    configuration

 .../bindings/mfd/atmel,flexcom.yaml           | 134 ++++++++++++++++++
 .../devicetree/bindings/mfd/atmel-flexcom.txt |  63 --------
 drivers/mfd/atmel-flexcom.c                   |  93 +++++++++++-
 3 files changed, 226 insertions(+), 64 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
 delete mode 100644 Documentation/devicetree/bindings/mfd/atmel-flexcom.txt

Comments

Claudiu Beznea June 8, 2022, 7:35 a.m. UTC | #1
On 07.06.2022 17:47, Kavyasree Kotagiri wrote:
> LAN966x SoC have 5 flexcoms. Each flexcom has 2 chip-selects.
> For each chip select of each flexcom there is a configuration
> register FLEXCOM_SHARED[0-4]:SS_MASK[0-1]. The width of
> configuration register is 21 because there are 21 shared pins
> on each of which the chip select can be mapped. Each bit of the
> register represents a different FLEXCOM_SHARED pin.
> 
> Signed-off-by: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
> ---
> v1 -> v2:
>  - use GENMASK for mask, macros for maximum allowed values.
>  - use u32 values for flexcom chipselects instead of strings.
>  - disable clock in case of errors.
> 
>  drivers/mfd/atmel-flexcom.c | 93 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 92 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
> index 33caa4fba6af..ac700a85b46f 100644
> --- a/drivers/mfd/atmel-flexcom.c
> +++ b/drivers/mfd/atmel-flexcom.c
> @@ -28,15 +28,68 @@
>  #define FLEX_MR_OPMODE(opmode)	(((opmode) << FLEX_MR_OPMODE_OFFSET) &	\
>  				 FLEX_MR_OPMODE_MASK)
>  
> +/* LAN966x flexcom shared register offsets */
> +#define FLEX_SHRD_SS_MASK_0	0x0
> +#define FLEX_SHRD_SS_MASK_1	0x4
> +#define FLEX_SHRD_PIN_MAX	20
> +#define FLEX_CS_MAX		1
> +#define FLEX_SHRD_MASK		GENMASK(20, 0)
> +
> +struct atmel_flex_caps {
> +	bool has_flx_cs;
> +};
> +
>  struct atmel_flexcom {
>  	void __iomem *base;
> +	void __iomem *flexcom_shared_base;
>  	u32 opmode;
>  	struct clk *clk;
>  };
>  
> +static int atmel_flexcom_lan966x_cs_config(struct platform_device *pdev)
> +{
> +	struct atmel_flexcom *ddata = dev_get_drvdata(&pdev->dev);
> +	struct device_node *np = pdev->dev.of_node;
> +	u32 flx_shrd_pins[2], flx_cs[2], val;
> +	int err, i, count;
> +
> +	count = of_property_count_u32_elems(np, "microchip,flx-shrd-pins");
> +	if (count <= 0 || count > 2) {
> +		dev_err(&pdev->dev, "Invalid %s property (%d)\n", "flx-shrd-pins",
> +				count);
> +		return -EINVAL;
> +	}
> +
> +	err = of_property_read_u32_array(np, "microchip,flx-shrd-pins", flx_shrd_pins, count);
> +	if (err)
> +		return err;
> +
> +	err = of_property_read_u32_array(np, "microchip,flx-cs", flx_cs, count);
> +	if (err)
> +		return err;
> +
> +	for (i = 0; i < count; i++) {
> +		if (flx_shrd_pins[i] > FLEX_SHRD_PIN_MAX)
> +			return -EINVAL;
> +
> +		if (flx_cs[i] > FLEX_CS_MAX)
> +			return -EINVAL;
> +
> +		val = ~(1 << flx_shrd_pins[i]) & FLEX_SHRD_MASK;
> +
> +		if (flx_cs[i] == 0)
> +			writel(val, ddata->flexcom_shared_base + FLEX_SHRD_SS_MASK_0);
> +		else
> +			writel(val, ddata->flexcom_shared_base + FLEX_SHRD_SS_MASK_1);

There is still an open question on this topic from previous version.

> +	}
> +
> +	return 0;
> +}
> +
>  static int atmel_flexcom_probe(struct platform_device *pdev)
>  {
>  	struct device_node *np = pdev->dev.of_node;
> +	const struct atmel_flex_caps *caps;
>  	struct resource *res;
>  	struct atmel_flexcom *ddata;
>  	int err;
> @@ -76,13 +129,51 @@ static int atmel_flexcom_probe(struct platform_device *pdev)
>  	 */
>  	writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base + FLEX_MR);
>  
> +	caps = of_device_get_match_data(&pdev->dev);
> +	if (!caps) {
> +		dev_err(&pdev->dev, "Could not retrieve flexcom caps\n");
> +		clk_disable_unprepare(ddata->clk);

Could you keep a common path to disable the clock? A goto label something
like this:
		ret = -EINVAL;
		got clk_disable_unprepare;

> +		return -EINVAL;
> +	}
> +
> +	if (caps->has_flx_cs) {
> +		ddata->flexcom_shared_base = devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
> +		if (IS_ERR(ddata->flexcom_shared_base)) {
> +			clk_disable_unprepare(ddata->clk);
> +			return dev_err_probe(&pdev->dev,
> +					PTR_ERR(ddata->flexcom_shared_base),
> +					"failed to get flexcom shared base address\n");
			ret = dev_err_probe(...);
			goto clk_disable_unprepare;
> +		}
> +
> +		err = atmel_flexcom_lan966x_cs_config(pdev);
> +		if (err) {
> +			clk_disable_unprepare(ddata->clk);
> +			return err;
			goto clk_disable_unprepare;
> +		}
> +	}
> +

clk_unprepare:
>  	clk_disable_unprepare(ddata->clk);
	if (ret)
		return ret;
>  
>  	return devm_of_platform_populate(&pdev->dev);
>  }
>  
> +static const struct atmel_flex_caps atmel_flexcom_caps = {};
> +
> +static const struct atmel_flex_caps lan966x_flexcom_caps = {
> +	.has_flx_cs = true,
> +};
> +
>  static const struct of_device_id atmel_flexcom_of_match[] = {
> -	{ .compatible = "atmel,sama5d2-flexcom" },
> +	{
> +		.compatible = "atmel,sama5d2-flexcom",
> +		.data = &atmel_flexcom_caps,
> +	},
> +
> +	{
> +		.compatible = "microchip,lan966x-flexcom",
> +		.data = &lan966x_flexcom_caps,
> +	},
> +
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
Kavyasree Kotagiri June 8, 2022, 8:20 a.m. UTC | #2
> > LAN966x SoC have 5 flexcoms. Each flexcom has 2 chip-selects.
> > For each chip select of each flexcom there is a configuration
> > register FLEXCOM_SHARED[0-4]:SS_MASK[0-1]. The width of
> > configuration register is 21 because there are 21 shared pins
> > on each of which the chip select can be mapped. Each bit of the
> > register represents a different FLEXCOM_SHARED pin.
> >
> > Signed-off-by: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
> > ---
> > v1 -> v2:
> >  - use GENMASK for mask, macros for maximum allowed values.
> >  - use u32 values for flexcom chipselects instead of strings.
> >  - disable clock in case of errors.
> >
> >  drivers/mfd/atmel-flexcom.c | 93
> ++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 92 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
> > index 33caa4fba6af..ac700a85b46f 100644
> > --- a/drivers/mfd/atmel-flexcom.c
> > +++ b/drivers/mfd/atmel-flexcom.c
> > @@ -28,15 +28,68 @@
> >  #define FLEX_MR_OPMODE(opmode)	(((opmode) <<
> FLEX_MR_OPMODE_OFFSET) &	\
> >  				 FLEX_MR_OPMODE_MASK)
> >
> > +/* LAN966x flexcom shared register offsets */
> > +#define FLEX_SHRD_SS_MASK_0	0x0
> > +#define FLEX_SHRD_SS_MASK_1	0x4
> > +#define FLEX_SHRD_PIN_MAX	20
> > +#define FLEX_CS_MAX		1
> > +#define FLEX_SHRD_MASK		GENMASK(20, 0)
> > +
> > +struct atmel_flex_caps {
> > +	bool has_flx_cs;
> > +};
> > +
> >  struct atmel_flexcom {
> >  	void __iomem *base;
> > +	void __iomem *flexcom_shared_base;
> >  	u32 opmode;
> >  	struct clk *clk;
> >  };
> >
> > +static int atmel_flexcom_lan966x_cs_config(struct platform_device *pdev)
> > +{
> > +	struct atmel_flexcom *ddata = dev_get_drvdata(&pdev->dev);
> > +	struct device_node *np = pdev->dev.of_node;
> > +	u32 flx_shrd_pins[2], flx_cs[2], val;
> > +	int err, i, count;
> > +
> > +	count = of_property_count_u32_elems(np, "microchip,flx-shrd-
> pins");
> > +	if (count <= 0 || count > 2) {
> > +		dev_err(&pdev->dev, "Invalid %s property (%d)\n", "flx-shrd-
> pins",
> > +				count);
> > +		return -EINVAL;
> > +	}
> > +
> > +	err = of_property_read_u32_array(np, "microchip,flx-shrd-pins",
> flx_shrd_pins, count);
> > +	if (err)
> > +		return err;
> > +
> > +	err = of_property_read_u32_array(np, "microchip,flx-cs", flx_cs,
> count);
> > +	if (err)
> > +		return err;
> > +
> > +	for (i = 0; i < count; i++) {
> > +		if (flx_shrd_pins[i] > FLEX_SHRD_PIN_MAX)
> > +			return -EINVAL;
> > +
> > +		if (flx_cs[i] > FLEX_CS_MAX)
> > +			return -EINVAL;
> > +
> > +		val = ~(1 << flx_shrd_pins[i]) & FLEX_SHRD_MASK;
> > +
> > +		if (flx_cs[i] == 0)
> > +			writel(val, ddata->flexcom_shared_base +
> FLEX_SHRD_SS_MASK_0);
> > +		else
> > +			writel(val, ddata->flexcom_shared_base +
> FLEX_SHRD_SS_MASK_1);
> 
> There is still an open question on this topic from previous version.
> 
https://lore.kernel.org/linux-arm-kernel/PH0PR11MB48724DE09A50D67F1EA9FBE092D89@PH0PR11MB4872.namprd11.prod.outlook.com/
As part of comments from Peter Rosin - Instead of using mux driver, This patch is introducing 
new dt-properties in atmel-flexom driver itlself to configure Flexcom shared registers. 
Based on the chip-select(0 or 1) to be mapped to flexcom shared pin, write to the
respective register. 
If you still have any questions, please comment.

> > +	}
> > +
> > +	return 0;
> > +}
> > +
> >  static int atmel_flexcom_probe(struct platform_device *pdev)
> >  {
> >  	struct device_node *np = pdev->dev.of_node;
> > +	const struct atmel_flex_caps *caps;
> >  	struct resource *res;
> >  	struct atmel_flexcom *ddata;
> >  	int err;
> > @@ -76,13 +129,51 @@ static int atmel_flexcom_probe(struct
> platform_device *pdev)
> >  	 */
> >  	writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base +
> FLEX_MR);
> >
> > +	caps = of_device_get_match_data(&pdev->dev);
> > +	if (!caps) {
> > +		dev_err(&pdev->dev, "Could not retrieve flexcom caps\n");
> > +		clk_disable_unprepare(ddata->clk);
> 
> Could you keep a common path to disable the clock? A goto label something
> like this:
> 		ret = -EINVAL;
> 		got clk_disable_unprepare;
> 
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (caps->has_flx_cs) {
> > +		ddata->flexcom_shared_base =
> devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
> > +		if (IS_ERR(ddata->flexcom_shared_base)) {
> > +			clk_disable_unprepare(ddata->clk);
> > +			return dev_err_probe(&pdev->dev,
> > +					PTR_ERR(ddata-
> >flexcom_shared_base),
> > +					"failed to get flexcom shared base
> address\n");
> 			ret = dev_err_probe(...);
> 			goto clk_disable_unprepare;
> > +		}
> > +
> > +		err = atmel_flexcom_lan966x_cs_config(pdev);
> > +		if (err) {
> > +			clk_disable_unprepare(ddata->clk);
> > +			return err;
> 			goto clk_disable_unprepare;
> > +		}
> > +	}
> > +
> 
> clk_unprepare:
> >  	clk_disable_unprepare(ddata->clk);
> 	if (ret)
> 		return ret;
> >
> >  	return devm_of_platform_populate(&pdev->dev);
> >  }
> >
> > +static const struct atmel_flex_caps atmel_flexcom_caps = {};
> > +
> > +static const struct atmel_flex_caps lan966x_flexcom_caps = {
> > +	.has_flx_cs = true,
> > +};
> > +
> >  static const struct of_device_id atmel_flexcom_of_match[] = {
> > -	{ .compatible = "atmel,sama5d2-flexcom" },
> > +	{
> > +		.compatible = "atmel,sama5d2-flexcom",
> > +		.data = &atmel_flexcom_caps,
> > +	},
> > +
> > +	{
> > +		.compatible = "microchip,lan966x-flexcom",
> > +		.data = &lan966x_flexcom_caps,
> > +	},
> > +
> >  	{ /* sentinel */ }
> >  };
> >  MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
Krzysztof Kozlowski June 8, 2022, 9:33 a.m. UTC | #3
On 08/06/2022 11:31, Kavyasree.Kotagiri@microchip.com wrote:
>>> Convert the Atmel flexcom device tree bindings to json schema.
>>>
>>> Signed-off-by: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
>>> ---
>>> v1 -> v2:
>>>  - Fix title.
>>>
>>>  .../bindings/mfd/atmel,flexcom.yaml           | 97 +++++++++++++++++++
>>>  .../devicetree/bindings/mfd/atmel-flexcom.txt | 63 ------------
>>>  2 files changed, 97 insertions(+), 63 deletions(-)
>>>  create mode 100644
>> Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
>>>  delete mode 100644 Documentation/devicetree/bindings/mfd/atmel-
>> flexcom.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
>> b/Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
>>> new file mode 100644
>>> index 000000000000..05cb6ebb4b2a
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml
>>> @@ -0,0 +1,97 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/mfd/atmel,flexcom.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: Atmel Flexcom (Flexible Serial Communication Unit)
>>> +
>>> +maintainers:
>>> +  - Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
>>> +
>>> +description:
>>> +  The Atmel Flexcom is just a wrapper which embeds a SPI controller,
>>> +  an I2C controller and an USART. Only one function can be used at a
>>> +  time and is chosen at boot time according to the device tree.
>>> +
>>> +properties:
>>> +  compatible:
>>> +    const: atmel,sama5d2-flexcom
>>
>> Same comment applies as before... Your previous set was better here and
>> for some reason you decided to change it. This should be enum so you
>> avoid useless change next patch.
>>
> Thanks for your comments.
> Do you mean use "enum" instead of "const" in current patch itself and add new compatible in 2/3 patch?

Yes. This is how you did it in previous patchsets.

Best regards,
Krzysztof
Claudiu Beznea June 8, 2022, 2:17 p.m. UTC | #4
On 08.06.2022 11:20, Kavyasree Kotagiri - I30978 wrote:
>>> LAN966x SoC have 5 flexcoms. Each flexcom has 2 chip-selects.
>>> For each chip select of each flexcom there is a configuration
>>> register FLEXCOM_SHARED[0-4]:SS_MASK[0-1]. The width of
>>> configuration register is 21 because there are 21 shared pins
>>> on each of which the chip select can be mapped. Each bit of the
>>> register represents a different FLEXCOM_SHARED pin.
>>>
>>> Signed-off-by: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
>>> ---
>>> v1 -> v2:
>>>  - use GENMASK for mask, macros for maximum allowed values.
>>>  - use u32 values for flexcom chipselects instead of strings.
>>>  - disable clock in case of errors.
>>>
>>>  drivers/mfd/atmel-flexcom.c | 93
>> ++++++++++++++++++++++++++++++++++++-
>>>  1 file changed, 92 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
>>> index 33caa4fba6af..ac700a85b46f 100644
>>> --- a/drivers/mfd/atmel-flexcom.c
>>> +++ b/drivers/mfd/atmel-flexcom.c
>>> @@ -28,15 +28,68 @@
>>>  #define FLEX_MR_OPMODE(opmode)	(((opmode) <<
>> FLEX_MR_OPMODE_OFFSET) &	\
>>>  				 FLEX_MR_OPMODE_MASK)
>>>
>>> +/* LAN966x flexcom shared register offsets */
>>> +#define FLEX_SHRD_SS_MASK_0	0x0
>>> +#define FLEX_SHRD_SS_MASK_1	0x4
>>> +#define FLEX_SHRD_PIN_MAX	20
>>> +#define FLEX_CS_MAX		1
>>> +#define FLEX_SHRD_MASK		GENMASK(20, 0)
>>> +
>>> +struct atmel_flex_caps {
>>> +	bool has_flx_cs;
>>> +};
>>> +
>>>  struct atmel_flexcom {
>>>  	void __iomem *base;
>>> +	void __iomem *flexcom_shared_base;
>>>  	u32 opmode;
>>>  	struct clk *clk;
>>>  };
>>>
>>> +static int atmel_flexcom_lan966x_cs_config(struct platform_device *pdev)
>>> +{
>>> +	struct atmel_flexcom *ddata = dev_get_drvdata(&pdev->dev);
>>> +	struct device_node *np = pdev->dev.of_node;
>>> +	u32 flx_shrd_pins[2], flx_cs[2], val;
>>> +	int err, i, count;
>>> +
>>> +	count = of_property_count_u32_elems(np, "microchip,flx-shrd-
>> pins");
>>> +	if (count <= 0 || count > 2) {
>>> +		dev_err(&pdev->dev, "Invalid %s property (%d)\n", "flx-shrd-
>> pins",
>>> +				count);
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	err = of_property_read_u32_array(np, "microchip,flx-shrd-pins",
>> flx_shrd_pins, count);
>>> +	if (err)
>>> +		return err;
>>> +
>>> +	err = of_property_read_u32_array(np, "microchip,flx-cs", flx_cs,
>> count);
>>> +	if (err)
>>> +		return err;
>>> +
>>> +	for (i = 0; i < count; i++) {
>>> +		if (flx_shrd_pins[i] > FLEX_SHRD_PIN_MAX)
>>> +			return -EINVAL;
>>> +
>>> +		if (flx_cs[i] > FLEX_CS_MAX)
>>> +			return -EINVAL;
>>> +
>>> +		val = ~(1 << flx_shrd_pins[i]) & FLEX_SHRD_MASK;
>>> +
>>> +		if (flx_cs[i] == 0)
>>> +			writel(val, ddata->flexcom_shared_base +
>> FLEX_SHRD_SS_MASK_0);
>>> +		else
>>> +			writel(val, ddata->flexcom_shared_base +
>> FLEX_SHRD_SS_MASK_1);
>>
>> There is still an open question on this topic from previous version.
>>
> https://lore.kernel.org/linux-arm-kernel/PH0PR11MB48724DE09A50D67F1EA9FBE092D89@PH0PR11MB4872.namprd11.prod.outlook.com/

"previous version" meant for me this the one at [1]... Another point that
the versioning of this series is bad.

The question was the following:

"I may miss something but I don't see here the approach you introduced in [1]:

+			err = mux_control_select(flx_mux, args.args[0]);
+			if (!err) {
+				mux_control_deselect(flx_mux);
"

As I had in mind that you said you need mux_control_deselect() because your
serial remain blocked otherwise (but I don't find that in the comments of
[1]). And I don't see something similar to mux_control_deselect() being
called in this patch.

[1]
https://lore.kernel.org/linux-arm-kernel/5f9fcc33-cc0f-c404-cf7f-cb73f60154ff@microchip.com/

> As part of comments from Peter Rosin - Instead of using mux driver, This patch is introducing 
> new dt-properties in atmel-flexom driver itlself to configure Flexcom shared registers. 
> Based on the chip-select(0 or 1) to be mapped to flexcom shared pin, write to the
> respective register. 
> If you still have any questions, please comment.
> 
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>>  static int atmel_flexcom_probe(struct platform_device *pdev)
>>>  {
>>>  	struct device_node *np = pdev->dev.of_node;
>>> +	const struct atmel_flex_caps *caps;
>>>  	struct resource *res;
>>>  	struct atmel_flexcom *ddata;
>>>  	int err;
>>> @@ -76,13 +129,51 @@ static int atmel_flexcom_probe(struct
>> platform_device *pdev)
>>>  	 */
>>>  	writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base +
>> FLEX_MR);
>>>
>>> +	caps = of_device_get_match_data(&pdev->dev);
>>> +	if (!caps) {
>>> +		dev_err(&pdev->dev, "Could not retrieve flexcom caps\n");
>>> +		clk_disable_unprepare(ddata->clk);
>>
>> Could you keep a common path to disable the clock? A goto label something
>> like this:
>> 		ret = -EINVAL;
>> 		got clk_disable_unprepare;
>>
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	if (caps->has_flx_cs) {
>>> +		ddata->flexcom_shared_base =
>> devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
>>> +		if (IS_ERR(ddata->flexcom_shared_base)) {
>>> +			clk_disable_unprepare(ddata->clk);
>>> +			return dev_err_probe(&pdev->dev,
>>> +					PTR_ERR(ddata-
>>> flexcom_shared_base),
>>> +					"failed to get flexcom shared base
>> address\n");
>> 			ret = dev_err_probe(...);
>> 			goto clk_disable_unprepare;
>>> +		}
>>> +
>>> +		err = atmel_flexcom_lan966x_cs_config(pdev);
>>> +		if (err) {
>>> +			clk_disable_unprepare(ddata->clk);
>>> +			return err;
>> 			goto clk_disable_unprepare;
>>> +		}
>>> +	}
>>> +
>>
>> clk_unprepare:
>>>  	clk_disable_unprepare(ddata->clk);
>> 	if (ret)
>> 		return ret;
>>>
>>>  	return devm_of_platform_populate(&pdev->dev);
>>>  }
>>>
>>> +static const struct atmel_flex_caps atmel_flexcom_caps = {};
>>> +
>>> +static const struct atmel_flex_caps lan966x_flexcom_caps = {
>>> +	.has_flx_cs = true,
>>> +};
>>> +
>>>  static const struct of_device_id atmel_flexcom_of_match[] = {
>>> -	{ .compatible = "atmel,sama5d2-flexcom" },
>>> +	{
>>> +		.compatible = "atmel,sama5d2-flexcom",
>>> +		.data = &atmel_flexcom_caps,
>>> +	},
>>> +
>>> +	{
>>> +		.compatible = "microchip,lan966x-flexcom",
>>> +		.data = &lan966x_flexcom_caps,
>>> +	},
>>> +
>>>  	{ /* sentinel */ }
>>>  };
>>>  MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
>
Kavyasree Kotagiri June 9, 2022, 5:18 a.m. UTC | #5
> >>> LAN966x SoC have 5 flexcoms. Each flexcom has 2 chip-selects.
> >>> For each chip select of each flexcom there is a configuration
> >>> register FLEXCOM_SHARED[0-4]:SS_MASK[0-1]. The width of
> >>> configuration register is 21 because there are 21 shared pins
> >>> on each of which the chip select can be mapped. Each bit of the
> >>> register represents a different FLEXCOM_SHARED pin.
> >>>
> >>> Signed-off-by: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
> >>> ---
> >>> v1 -> v2:
> >>>  - use GENMASK for mask, macros for maximum allowed values.
> >>>  - use u32 values for flexcom chipselects instead of strings.
> >>>  - disable clock in case of errors.
> >>>
> >>>  drivers/mfd/atmel-flexcom.c | 93
> >> ++++++++++++++++++++++++++++++++++++-
> >>>  1 file changed, 92 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
> >>> index 33caa4fba6af..ac700a85b46f 100644
> >>> --- a/drivers/mfd/atmel-flexcom.c
> >>> +++ b/drivers/mfd/atmel-flexcom.c
> >>> @@ -28,15 +28,68 @@
> >>>  #define FLEX_MR_OPMODE(opmode)	(((opmode) <<
> >> FLEX_MR_OPMODE_OFFSET) &	\
> >>>  				 FLEX_MR_OPMODE_MASK)
> >>>
> >>> +/* LAN966x flexcom shared register offsets */
> >>> +#define FLEX_SHRD_SS_MASK_0	0x0
> >>> +#define FLEX_SHRD_SS_MASK_1	0x4
> >>> +#define FLEX_SHRD_PIN_MAX	20
> >>> +#define FLEX_CS_MAX		1
> >>> +#define FLEX_SHRD_MASK		GENMASK(20, 0)
> >>> +
> >>> +struct atmel_flex_caps {
> >>> +	bool has_flx_cs;
> >>> +};
> >>> +
> >>>  struct atmel_flexcom {
> >>>  	void __iomem *base;
> >>> +	void __iomem *flexcom_shared_base;
> >>>  	u32 opmode;
> >>>  	struct clk *clk;
> >>>  };
> >>>
> >>> +static int atmel_flexcom_lan966x_cs_config(struct platform_device
> *pdev)
> >>> +{
> >>> +	struct atmel_flexcom *ddata = dev_get_drvdata(&pdev->dev);
> >>> +	struct device_node *np = pdev->dev.of_node;
> >>> +	u32 flx_shrd_pins[2], flx_cs[2], val;
> >>> +	int err, i, count;
> >>> +
> >>> +	count = of_property_count_u32_elems(np, "microchip,flx-shrd-
> >> pins");
> >>> +	if (count <= 0 || count > 2) {
> >>> +		dev_err(&pdev->dev, "Invalid %s property (%d)\n", "flx-shrd-
> >> pins",
> >>> +				count);
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	err = of_property_read_u32_array(np, "microchip,flx-shrd-pins",
> >> flx_shrd_pins, count);
> >>> +	if (err)
> >>> +		return err;
> >>> +
> >>> +	err = of_property_read_u32_array(np, "microchip,flx-cs", flx_cs,
> >> count);
> >>> +	if (err)
> >>> +		return err;
> >>> +
> >>> +	for (i = 0; i < count; i++) {
> >>> +		if (flx_shrd_pins[i] > FLEX_SHRD_PIN_MAX)
> >>> +			return -EINVAL;
> >>> +
> >>> +		if (flx_cs[i] > FLEX_CS_MAX)
> >>> +			return -EINVAL;
> >>> +
> >>> +		val = ~(1 << flx_shrd_pins[i]) & FLEX_SHRD_MASK;
> >>> +
> >>> +		if (flx_cs[i] == 0)
> >>> +			writel(val, ddata->flexcom_shared_base +
> >> FLEX_SHRD_SS_MASK_0);
> >>> +		else
> >>> +			writel(val, ddata->flexcom_shared_base +
> >> FLEX_SHRD_SS_MASK_1);
> >>
> >> There is still an open question on this topic from previous version.
> >>
> > https://lore.kernel.org/linux-arm-
> kernel/PH0PR11MB48724DE09A50D67F1EA9FBE092D89@PH0PR11MB4872.n
> amprd11.prod.outlook.com/
> 
> "previous version" meant for me this the one at [1]... Another point that
> the versioning of this series is bad.
> 
> The question was the following:
> 
> "I may miss something but I don't see here the approach you introduced in
> [1]:
> 
> +			err = mux_control_select(flx_mux, args.args[0]);
> +			if (!err) {
> +				mux_control_deselect(flx_mux);
> "
> 
> As I had in mind that you said you need mux_control_deselect() because
> your
> serial remain blocked otherwise (but I don't find that in the comments of
> [1]). And I don't see something similar to mux_control_deselect() being
> called in this patch.
> 
> [1]
> https://lore.kernel.org/linux-arm-kernel/5f9fcc33-cc0f-c404-cf7f-
> cb73f60154ff@microchip.com/
> 
> > As part of comments from Peter Rosin - Instead of using mux driver, This
> patch is introducing
> > new dt-properties in atmel-flexom driver itlself to configure Flexcom
> shared registers.
> > Based on the chip-select(0 or 1) to be mapped to flexcom shared pin, write
> to the
> > respective register.
> > If you still have any questions, please comment.
> >
https://lore.kernel.org/linux-arm-kernel/PH0PR11MB48724DE09A50D67F1EA9FBE092D89@PH0PR11MB4872.namprd11.prod.outlook.com/
To avoid confusion, I stopped continuing with above patch versioning(mux driver approach).
I started new patch series in which I am configuring FLEXCOM_SHARED[0-4]:SS_MASK[0-1]
registers in atmel-flexcom.c driver using new DT-properties, mux driver approach is no more followed
as suggested by Peter Rosin:
"
> If you are content with just programming a fixed set of values to
> a couple of registers depending on how the board is wired, some
> extra DT property on some node related to the flexcom seems like
> a better fit than a mux driver.
Based on your inputs, I planned to send a new patch with new DT properties
introduced in atmel-flexcom.c driver rather than mux driver.

Thanks,
Kavya
"

Thanks,
Kavya

> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>>  static int atmel_flexcom_probe(struct platform_device *pdev)
> >>>  {
> >>>  	struct device_node *np = pdev->dev.of_node;
> >>> +	const struct atmel_flex_caps *caps;
> >>>  	struct resource *res;
> >>>  	struct atmel_flexcom *ddata;
> >>>  	int err;
> >>> @@ -76,13 +129,51 @@ static int atmel_flexcom_probe(struct
> >> platform_device *pdev)
> >>>  	 */
> >>>  	writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base +
> >> FLEX_MR);
> >>>
> >>> +	caps = of_device_get_match_data(&pdev->dev);
> >>> +	if (!caps) {
> >>> +		dev_err(&pdev->dev, "Could not retrieve flexcom caps\n");
> >>> +		clk_disable_unprepare(ddata->clk);
> >>
> >> Could you keep a common path to disable the clock? A goto label
> something
> >> like this:
> >> 		ret = -EINVAL;
> >> 		got clk_disable_unprepare;
> >>
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	if (caps->has_flx_cs) {
> >>> +		ddata->flexcom_shared_base =
> >> devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
> >>> +		if (IS_ERR(ddata->flexcom_shared_base)) {
> >>> +			clk_disable_unprepare(ddata->clk);
> >>> +			return dev_err_probe(&pdev->dev,
> >>> +					PTR_ERR(ddata-
> >>> flexcom_shared_base),
> >>> +					"failed to get flexcom shared base
> >> address\n");
> >> 			ret = dev_err_probe(...);
> >> 			goto clk_disable_unprepare;
> >>> +		}
> >>> +
> >>> +		err = atmel_flexcom_lan966x_cs_config(pdev);
> >>> +		if (err) {
> >>> +			clk_disable_unprepare(ddata->clk);
> >>> +			return err;
> >> 			goto clk_disable_unprepare;
> >>> +		}
> >>> +	}
> >>> +
> >>
> >> clk_unprepare:
> >>>  	clk_disable_unprepare(ddata->clk);
> >> 	if (ret)
> >> 		return ret;
> >>>
> >>>  	return devm_of_platform_populate(&pdev->dev);
> >>>  }
> >>>
> >>> +static const struct atmel_flex_caps atmel_flexcom_caps = {};
> >>> +
> >>> +static const struct atmel_flex_caps lan966x_flexcom_caps = {
> >>> +	.has_flx_cs = true,
> >>> +};
> >>> +
> >>>  static const struct of_device_id atmel_flexcom_of_match[] = {
> >>> -	{ .compatible = "atmel,sama5d2-flexcom" },
> >>> +	{
> >>> +		.compatible = "atmel,sama5d2-flexcom",
> >>> +		.data = &atmel_flexcom_caps,
> >>> +	},
> >>> +
> >>> +	{
> >>> +		.compatible = "microchip,lan966x-flexcom",
> >>> +		.data = &lan966x_flexcom_caps,
> >>> +	},
> >>> +
> >>>  	{ /* sentinel */ }
> >>>  };
> >>>  MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
> >
Claudiu Beznea June 10, 2022, 9:06 a.m. UTC | #6
On 09.06.2022 16:34, Kavyasree Kotagiri - I30978 wrote:
> 
>>>>>> LAN966x SoC have 5 flexcoms. Each flexcom has 2 chip-selects.
>>>>>> For each chip select of each flexcom there is a configuration
>>>>>> register FLEXCOM_SHARED[0-4]:SS_MASK[0-1]. The width of
>>>>>> configuration register is 21 because there are 21 shared pins
>>>>>> on each of which the chip select can be mapped. Each bit of the
>>>>>> register represents a different FLEXCOM_SHARED pin.
>>>>>> Signed-off-by: Kavyasree Kotagiri <kavyasree.kotagiri@microchip.com>
>>>>>> ---
>>>>>> v1 -> v2:
>>>>>> - use GENMASK for mask, macros for maximum allowed values.
>>>>>> - use u32 values for flexcom chipselects instead of strings.
>>>>>> - disable clock in case of errors.
>>>>>> drivers/mfd/atmel-flexcom.c | 93
>>>>> ++++++++++++++++++++++++++++++++++++-
>>>>>> 1 file changed, 92 insertions(+), 1 deletion(-)
>>>>>> diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c
>>>>>> index 33caa4fba6af..ac700a85b46f 100644
>>>>>> --- a/drivers/mfd/atmel-flexcom.c
>>>>>> +++ b/drivers/mfd/atmel-flexcom.c
>>>>>> @@ -28,15 +28,68 @@
>>>>>> #define FLEX_MR_OPMODE(opmode)    (((opmode) <<
>>>>> FLEX_MR_OPMODE_OFFSET) &    \
>>>>>>                FLEX_MR_OPMODE_MASK)
>>>>>> +/* LAN966x flexcom shared register offsets */
>>>>>> +#define FLEX_SHRD_SS_MASK_0    0x0
>>>>>> +#define FLEX_SHRD_SS_MASK_1    0x4
>>>>>> +#define FLEX_SHRD_PIN_MAX    20
>>>>>> +#define FLEX_CS_MAX        1
>>>>>> +#define FLEX_SHRD_MASK        GENMASK(20, 0)
>>>>>> +
>>>>>> +struct atmel_flex_caps {
>>>>>> +    bool has_flx_cs;
>>>>>> +};
>>>>>> +
>>>>>> struct atmel_flexcom {
>>>>>>   void __iomem *base;
>>>>>> +    void __iomem *flexcom_shared_base;
>>>>>>   u32 opmode;
>>>>>>   struct clk *clk;
>>>>>> };
>>>>>> +static int atmel_flexcom_lan966x_cs_config(struct platform_device
>>> *pdev)
>>>>>> +{
>>>>>> +    struct atmel_flexcom *ddata = dev_get_drvdata(&pdev->dev);
>>>>>> +    struct device_node *np = pdev->dev.of_node;
>>>>>> +    u32 flx_shrd_pins[2], flx_cs[2], val;
>>>>>> +    int err, i, count;
>>>>>> +
>>>>>> +    count = of_property_count_u32_elems(np, "microchip,flx-shrd-
>>>>> pins");
>>>>>> +    if (count <= 0 || count > 2) {
>>>>>> +        dev_err(&pdev->dev, "Invalid %s property (%d)\n", "flx-shrd-
>>>>> pins",
>>>>>> +                count);
>>>>>> +        return -EINVAL;
>>>>>> +    }
>>>>>> +
>>>>>> +    err = of_property_read_u32_array(np, "microchip,flx-shrd-pins",
>>>>> flx_shrd_pins, count);
>>>>>> +    if (err)
>>>>>> +        return err;
>>>>>> +
>>>>>> +    err = of_property_read_u32_array(np, "microchip,flx-cs", flx_cs,
>>>>> count);
>>>>>> +    if (err)
>>>>>> +        return err;
>>>>>> +
>>>>>> +    for (i = 0; i < count; i++) {
>>>>>> +        if (flx_shrd_pins[i] > FLEX_SHRD_PIN_MAX)
>>>>>> +            return -EINVAL;
>>>>>> +
>>>>>> +        if (flx_cs[i] > FLEX_CS_MAX)
>>>>>> +            return -EINVAL;
>>>>>> +
>>>>>> +        val = ~(1 << flx_shrd_pins[i]) & FLEX_SHRD_MASK;
>>>>>> +
>>>>>> +        if (flx_cs[i] == 0)
>>>>>> +            writel(val, ddata->flexcom_shared_base +
>>>>> FLEX_SHRD_SS_MASK_0);
>>>>>> +        else
>>>>>> +            writel(val, ddata->flexcom_shared_base +
>>>>> FLEX_SHRD_SS_MASK_1);
>>>>> There is still an open question on this topic from previous version.
>>>> https://lore.kernel.org/linux-arm-
>>> kernel/PH0PR11MB48724DE09A50D67F1EA9FBE092D89@PH0PR11MB4872.n
>>> amprd11.prod.outlook.com/
>>> "previous version" meant for me this the one at [1]... Another point that
>>> the versioning of this series is bad.
>>> The question was the following:
>>> "I may miss something but I don't see here the approach you introduced in
>>> [1]:
>>> +            err = mux_control_select(flx_mux, args.args[0]);
>>> +            if (!err) {
>>> +                mux_control_deselect(flx_mux);
>>> "
>>> As I had in mind that you said you need mux_control_deselect() because
>>> your
>>> serial remain blocked otherwise (but I don't find that in the comments of
>>> [1]). And I don't see something similar to mux_control_deselect() being
>>> called in this patch.
>>> [1]
>>> https://lore.kernel.org/linux-arm-kernel/5f9fcc33-cc0f-c404-cf7f-
>>> cb73f60154ff@microchip.com/
>>>> As part of comments from Peter Rosin - Instead of using mux driver, This
>>> patch is introducing
>>>> new dt-properties in atmel-flexom driver itlself to configure Flexcom
>>> shared registers.
>>>> Based on the chip-select(0 or 1) to be mapped to flexcom shared pin, write
>>> to the
>>>> respective register.
>>>> If you still have any questions, please comment.
>> https://lore.kernel.org/linux-arm-kernel/PH0PR11MB48724DE09A50D67F1EA9FBE092D89@PH0PR11MB4872.namprd11.prod.outlook.com/
>> To avoid confusion, I stopped continuing with above patch versioning(mux driver approach).
>> I started new patch series in which I am configuring FLEXCOM_SHARED[0-4]:SS_MASK[0-1]
>> registers in atmel-flexcom.c driver using new DT-properties, mux driver approach is no more followed
>> as suggested by Peter Rosin:
>> "
>>> If you are content with just programming a fixed set of values to
>>> a couple of registers depending on how the board is wired, some
>>> extra DT property on some node related to the flexcom seems like
>>> a better fit than a mux driver.
>> Based on your inputs, I planned to send a new patch with new DT properties
>> introduced in atmel-flexcom.c driver rather than mux driver.
>>
>> Thanks,
>> Kavya
>> "
>>
>> Thanks,
>> Kavya
> 
> Hi Claudiu,
> 
> Please let me know if you still have any comments. If not, I will send my v3 with clk_disable_unprepare moved to goto and some minor fixes(irq flags) in dt-bindings.

I got it now after the talk we had on internal chat. Please go with v3.

Thank you,
Claudiu Beznea

> 
>>>>>> +    }
>>>>>> +
>>>>>> +    return 0;
>>>>>> +}
>>>>>> +
>>>>>> static int atmel_flexcom_probe(struct platform_device *pdev)
>>>>>> {
>>>>>>   struct device_node *np = pdev->dev.of_node;
>>>>>> +    const struct atmel_flex_caps *caps;
>>>>>>   struct resource *res;
>>>>>>   struct atmel_flexcom *ddata;
>>>>>>   int err;
>>>>>> @@ -76,13 +129,51 @@ static int atmel_flexcom_probe(struct
>>>>> platform_device *pdev)
>>>>>>    */
>>>>>>   writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base +
>>>>> FLEX_MR);
>>>>>> +    caps = of_device_get_match_data(&pdev->dev);
>>>>>> +    if (!caps) {
>>>>>> +        dev_err(&pdev->dev, "Could not retrieve flexcom caps\n");
>>>>>> +        clk_disable_unprepare(ddata->clk);
>>>>> Could you keep a common path to disable the clock? A goto label
>>> something
>>>>> like this:
>>>>>       ret = -EINVAL;
>>>>>       got clk_disable_unprepare;
>>>>>> +        return -EINVAL;
>>>>>> +    }
>>>>>> +
>>>>>> +    if (caps->has_flx_cs) {
>>>>>> +        ddata->flexcom_shared_base =
>>>>> devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
>>>>>> +        if (IS_ERR(ddata->flexcom_shared_base)) {
>>>>>> +            clk_disable_unprepare(ddata->clk);
>>>>>> +            return dev_err_probe(&pdev->dev,
>>>>>> +                    PTR_ERR(ddata-
>>>>>> flexcom_shared_base),
>>>>>> +                    "failed to get flexcom shared base
>>>>> address\n");
>>>>>           ret = dev_err_probe(...);
>>>>>           goto clk_disable_unprepare;
>>>>>> +        }
>>>>>> +
>>>>>> +        err = atmel_flexcom_lan966x_cs_config(pdev);
>>>>>> +        if (err) {
>>>>>> +            clk_disable_unprepare(ddata->clk);
>>>>>> +            return err;
>>>>>           goto clk_disable_unprepare;
>>>>>> +        }
>>>>>> +    }
>>>>>> +
>>>>> clk_unprepare:
>>>>>>   clk_disable_unprepare(ddata->clk);
>>>>>   if (ret)
>>>>>       return ret;
>>>>>>   return devm_of_platform_populate(&pdev->dev);
>>>>>> }
>>>>>> +static const struct atmel_flex_caps atmel_flexcom_caps = {};
>>>>>> +
>>>>>> +static const struct atmel_flex_caps lan966x_flexcom_caps = {
>>>>>> +    .has_flx_cs = true,
>>>>>> +};
>>>>>> +
>>>>>> static const struct of_device_id atmel_flexcom_of_match[] = {
>>>>>> -    { .compatible = "atmel,sama5d2-flexcom" },
>>>>>> +    {
>>>>>> +        .compatible = "atmel,sama5d2-flexcom",
>>>>>> +        .data = &atmel_flexcom_caps,
>>>>>> +    },
>>>>>> +
>>>>>> +    {
>>>>>> +        .compatible = "microchip,lan966x-flexcom",
>>>>>> +        .data = &lan966x_flexcom_caps,
>>>>>> +    },
>>>>>> +
>>>>>>   { /* sentinel */ }
>>>>>> };
>>>>>> MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
Krzysztof Kozlowski June 16, 2022, 1:47 p.m. UTC | #7
On 16/06/2022 02:20, Kavyasree.Kotagiri@microchip.com wrote:
>>
>> Yes. This is how you did it in previous patchsets.
>>
> I did so in v3 series, but below errors are reported on 1/3 patch:
> dtschema/dtc warnings/errors:
> /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/mfd/atmel,flexcom.yaml: properties:compatible:enum: 'atmel,sama5d2-flexcom' is not of type 'array'

I don't remember it but it's a simple fix of syntax.
Documentation/devicetree/bindings/arm/arm,cci-400.yaml


Best regards,
Krzysztof