[PATCH v12 0/7] spacemit: introduce P1 PMIC support

[PATCH v12 0/7] spacemit: introduce P1 PMIC support

[Alex Elder]

The SpacemiT P1 is an I2C-controlled PMIC that implements 6 buck
converters and 12 LDOs.  It contains a load switch, ADC channels,
GPIOs, a real-time clock, and a watchdog timer.

This series introduces a multifunction driver for the P1 PMIC as
well as drivers for its regulators and RTC.

The content of this version is identical to the previous one.
It has simply been rebased onto Linux v6.17-rc1.

					-Alex

This series is available here:
  https://github.com/riscstar/linux/tree/outgoing/pmic-v12

Between version 11 and version 12:
  - Simple rebase

Here is version 11 of this series:
  https://lore.kernel.org/lkml/20250803025812.373029-1-elder@riscstar.com/

Between version 10 and version 11:
  - Abandon trying to implement a simple_mfd_data->max_register field
  - Fix a missing dependency pointed out by the kernel test robot

Here is version 10 of this series:
  https://lore.kernel.org/lkml/20250726131003.3137282-1-elder@riscstar.com/

Between version 9 and version 10:
  - The #address-cells and #size-cells for the i2c8 DTS node
    were moved into its primary definition in "k1.dtsi".
  - The interrupts property for the i2c8 DTS node was moved
    below its clock-related properties.
  - The status property in the pmic@41 DTS node was dropped.
  - The function that provides the regmap_config structure
    to use was reworked a bit.
  - A new function was added to free the regmap_config
    structure after it's no longer needed.

Here is version 9 of this series:
  https://lore.kernel.org/lkml/20250724202511.499288-1-elder@riscstar.com/

Between version 8 and version 9:
  - The max_config value is always used if it is provided with the
    simple_mfd_data structure.
  - The regmap_config structure used is allocated dynamically if
    necessary; otherwise regmap_config_8r_8v is used.
  - A small duplicated comment is removed

Here is version 8 of this series:
  https://lore.kernel.org/lkml/20250710175107.1280221-1-elder@riscstar.com/

More complete history is available at that link.


Alex Elder (7):
  dt-bindings: mfd: add support the SpacemiT P1 PMIC
  mfd: simple-mfd-i2c: add SpacemiT P1 support
  regulator: spacemit: support SpacemiT P1 regulators
  rtc: spacemit: support the SpacemiT P1 RTC
  riscv: dts: spacemit: enable the i2c8 adapter
  riscv: dts: spacemit: define fixed regulators
  riscv: dts: spacemit: define regulator constraints

 .../devicetree/bindings/mfd/spacemit,p1.yaml  |  86 +++++++++
 .../boot/dts/spacemit/k1-bananapi-f3.dts      | 135 ++++++++++++++
 arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi  |   7 +
 arch/riscv/boot/dts/spacemit/k1.dtsi          |  13 ++
 drivers/mfd/Kconfig                           |  11 ++
 drivers/mfd/simple-mfd-i2c.c                  |  18 ++
 drivers/regulator/Kconfig                     |  13 ++
 drivers/regulator/Makefile                    |   1 +
 drivers/regulator/spacemit-p1.c               | 157 ++++++++++++++++
 drivers/rtc/Kconfig                           |  10 ++
 drivers/rtc/Makefile                          |   1 +
 drivers/rtc/rtc-spacemit-p1.c                 | 167 ++++++++++++++++++
 12 files changed, 619 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
 create mode 100644 drivers/regulator/spacemit-p1.c
 create mode 100644 drivers/rtc/rtc-spacemit-p1.c


base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585
-- 
2.48.1

[PATCH v12 1/7] dt-bindings: mfd: add support the SpacemiT P1 PMIC

[Alex Elder]

Enable the SpacemiT P1, which is an I2C-controlled PMIC.  Initially
only the RTC and regulators will be supported.

Signed-off-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
---
 .../devicetree/bindings/mfd/spacemit,p1.yaml  | 86 +++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/spacemit,p1.yaml

diff --git a/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml b/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
new file mode 100644
index 0000000000000..5cc34d4934b54
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/spacemit,p1.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SpacemiT P1 Power Management Integrated Circuit
+
+maintainers:
+  - Troy Mitchell <troymitchell988@gmail.com>
+
+description:
+  P1 is an I2C-controlled PMIC produced by SpacemiT.  It implements six
+  constant-on-time buck converters and twelve low-dropout regulators.
+  It also contains a load switch, watchdog timer, real-time clock, eight
+  12-bit ADC channels, and six GPIOs.  Additional details are available
+  in the "Power Stone/P1" section at the following link.
+    https://developer.spacemit.com/documentation
+
+properties:
+  compatible:
+    const: spacemit,p1
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  vin-supply:
+    description: Input supply phandle.
+
+  regulators:
+    type: object
+
+    patternProperties:
+      "^(buck[1-6]|aldo[1-4]|dldo[1-7])$":
+        type: object
+        $ref: /schemas/regulator/regulator.yaml#
+        unevaluatedProperties: false
+
+    unevaluatedProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        pmic@41 {
+            compatible = "spacemit,p1";
+            reg = <0x41>;
+            interrupts = <64>;
+
+            regulators {
+                buck1 {
+                    regulator-name = "buck1";
+                    regulator-min-microvolt = <500000>;
+                    regulator-max-microvolt = <3450000>;
+                    regulator-ramp-delay = <5000>;
+                    regulator-always-on;
+                };
+
+                aldo1 {
+                    regulator-name = "aldo1";
+                    regulator-min-microvolt = <500000>;
+                    regulator-max-microvolt = <3400000>;
+                    regulator-boot-on;
+                };
+
+                dldo1 {
+                    regulator-name = "dldo1";
+                    regulator-min-microvolt = <500000>;
+                    regulator-max-microvolt = <3400000>;
+                    regulator-boot-on;
+                };
+            };
+        };
+    };
-- 
2.48.1

Re: [PATCH v12 1/7] dt-bindings: mfd: add support the SpacemiT P1 PMIC

[Troy Mitchell]

On Tue, Aug 12, 2025 at 09:45:02PM -0500, Alex Elder wrote:
> Enable the SpacemiT P1, which is an I2C-controlled PMIC.  Initially
> only the RTC and regulators will be supported.
> 
> Signed-off-by: Alex Elder <elder@riscstar.com>
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
> ---
>  .../devicetree/bindings/mfd/spacemit,p1.yaml  | 86 +++++++++++++++++++
>  1 file changed, 86 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
> 
> diff --git a/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml b/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
> new file mode 100644
> index 0000000000000..5cc34d4934b54
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/spacemit,p1.yaml
> @@ -0,0 +1,86 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/spacemit,p1.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SpacemiT P1 Power Management Integrated Circuit
> +
> +maintainers:
> +  - Troy Mitchell <troymitchell988@gmail.com>
You can change it from this to my company email:
troy.mitchell@linux.spacemit.com

Acked-by: Troy Mitchell <troymitchell988@gmail.com>

                - Troy
> +
> +description:
> +  P1 is an I2C-controlled PMIC produced by SpacemiT.  It implements six
> +  constant-on-time buck converters and twelve low-dropout regulators.
> +  It also contains a load switch, watchdog timer, real-time clock, eight
> +  12-bit ADC channels, and six GPIOs.  Additional details are available
> +  in the "Power Stone/P1" section at the following link.
> +    https://developer.spacemit.com/documentation
> +
> +properties:
> +  compatible:
> +    const: spacemit,p1
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  vin-supply:
> +    description: Input supply phandle.
> +
> +  regulators:
> +    type: object
> +
> +    patternProperties:
> +      "^(buck[1-6]|aldo[1-4]|dldo[1-7])$":
> +        type: object
> +        $ref: /schemas/regulator/regulator.yaml#
> +        unevaluatedProperties: false
> +
> +    unevaluatedProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        pmic@41 {
> +            compatible = "spacemit,p1";
> +            reg = <0x41>;
> +            interrupts = <64>;
> +
> +            regulators {
> +                buck1 {
> +                    regulator-name = "buck1";
> +                    regulator-min-microvolt = <500000>;
> +                    regulator-max-microvolt = <3450000>;
> +                    regulator-ramp-delay = <5000>;
> +                    regulator-always-on;
> +                };
> +
> +                aldo1 {
> +                    regulator-name = "aldo1";
> +                    regulator-min-microvolt = <500000>;
> +                    regulator-max-microvolt = <3400000>;
> +                    regulator-boot-on;
> +                };
> +
> +                dldo1 {
> +                    regulator-name = "dldo1";
> +                    regulator-min-microvolt = <500000>;
> +                    regulator-max-microvolt = <3400000>;
> +                    regulator-boot-on;
> +                };
> +            };
> +        };
> +    };
> -- 
> 2.48.1
> 

Re: [PATCH v12 1/7] dt-bindings: mfd: add support the SpacemiT P1 PMIC

[Alex Elder]

On 8/13/25 7:19 AM, Troy Mitchell wrote:
> You can change it from this to my company email:
> troy.mitchell@linux.spacemit.com
> 
> Acked-by: Troy Mitchell<troymitchell988@gmail.com>
> 
>                  - Troy

I will make this change before I do a final version.	-Alex

[PATCH v12 2/7] mfd: simple-mfd-i2c: add SpacemiT P1 support

[Alex Elder]

Enable support for the RTC and regulators found in the SpacemiT P1
PMIC.  Support is implemented by the simple I2C MFD driver.

The P1 PMIC is normally implemented with the SpacemiT K1 SoC.  This
PMIC provides 6 buck converters and 12 LDO regulators.  It also
implements a switch, watchdog timer, real-time clock, and more.
Initially its RTC and regulators are supported.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 drivers/mfd/Kconfig          | 11 +++++++++++
 drivers/mfd/simple-mfd-i2c.c | 18 ++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 425c5fba6cb1e..4d6a5a3a27220 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1238,6 +1238,17 @@ config MFD_QCOM_RPM
 	  Say M here if you want to include support for the Qualcomm RPM as a
 	  module. This will build a module called "qcom_rpm".
 
+config MFD_SPACEMIT_P1
+	tristate "SpacemiT P1 PMIC"
+	depends on I2C
+	select MFD_SIMPLE_MFD_I2C
+	help
+	  This option supports the I2C-based SpacemiT P1 PMIC, which
+	  contains regulators, a power switch, GPIOs, an RTC, and more.
+	  This option is selected when any of the supported sub-devices
+	  is configured.  The basic functionality is implemented by the
+	  simple MFD I2C driver.
+
 config MFD_SPMI_PMIC
 	tristate "Qualcomm SPMI PMICs"
 	depends on ARCH_QCOM || COMPILE_TEST
diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
index 22159913bea03..47ffaac035cae 100644
--- a/drivers/mfd/simple-mfd-i2c.c
+++ b/drivers/mfd/simple-mfd-i2c.c
@@ -93,12 +93,30 @@ static const struct simple_mfd_data maxim_mon_max77705 = {
 	.mfd_cell_size = ARRAY_SIZE(max77705_sensor_cells),
 };
 
+
+static const struct regmap_config spacemit_p1_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static const struct mfd_cell spacemit_p1_cells[] = {
+	{ .name = "spacemit-p1-regulator", },
+	{ .name = "spacemit-p1-rtc", },
+};
+
+static const struct simple_mfd_data spacemit_p1 = {
+	.regmap_config = &spacemit_p1_regmap_config,
+	.mfd_cell = spacemit_p1_cells,
+	.mfd_cell_size = ARRAY_SIZE(spacemit_p1_cells),
+};
+
 static const struct of_device_id simple_mfd_i2c_of_match[] = {
 	{ .compatible = "kontron,sl28cpld" },
 	{ .compatible = "silergy,sy7636a", .data = &silergy_sy7636a},
 	{ .compatible = "maxim,max5970", .data = &maxim_max5970},
 	{ .compatible = "maxim,max5978", .data = &maxim_max5970},
 	{ .compatible = "maxim,max77705-battery", .data = &maxim_mon_max77705},
+	{ .compatible = "spacemit,p1", .data = &spacemit_p1, },
 	{}
 };
 MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);
-- 
2.48.1

Re: [PATCH v12 2/7] mfd: simple-mfd-i2c: add SpacemiT P1 support

[Troy Mitchell]

Hi, Alex,

I did not find any accesses to the P1 shutdown or reboot registers here.
Does this mean that the current series does not support reboot or shutdown?
If so, do you have any plans to support this functionality?
If I have misunderstood, please correct me.

Best regards,
Troy


On Tue, Aug 12, 2025 at 09:45:03PM -0500, Alex Elder wrote:
> Enable support for the RTC and regulators found in the SpacemiT P1
> PMIC.  Support is implemented by the simple I2C MFD driver.
> 
> The P1 PMIC is normally implemented with the SpacemiT K1 SoC.  This
> PMIC provides 6 buck converters and 12 LDO regulators.  It also
> implements a switch, watchdog timer, real-time clock, and more.
> Initially its RTC and regulators are supported.
> 
> Signed-off-by: Alex Elder <elder@riscstar.com>
> ---
>  drivers/mfd/Kconfig          | 11 +++++++++++
>  drivers/mfd/simple-mfd-i2c.c | 18 ++++++++++++++++++
>  2 files changed, 29 insertions(+)
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 425c5fba6cb1e..4d6a5a3a27220 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -1238,6 +1238,17 @@ config MFD_QCOM_RPM
>  	  Say M here if you want to include support for the Qualcomm RPM as a
>  	  module. This will build a module called "qcom_rpm".
>  
> +config MFD_SPACEMIT_P1
> +	tristate "SpacemiT P1 PMIC"
> +	depends on I2C
> +	select MFD_SIMPLE_MFD_I2C
> +	help
> +	  This option supports the I2C-based SpacemiT P1 PMIC, which
> +	  contains regulators, a power switch, GPIOs, an RTC, and more.
> +	  This option is selected when any of the supported sub-devices
> +	  is configured.  The basic functionality is implemented by the
> +	  simple MFD I2C driver.
> +
>  config MFD_SPMI_PMIC
>  	tristate "Qualcomm SPMI PMICs"
>  	depends on ARCH_QCOM || COMPILE_TEST
> diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
> index 22159913bea03..47ffaac035cae 100644
> --- a/drivers/mfd/simple-mfd-i2c.c
> +++ b/drivers/mfd/simple-mfd-i2c.c
> @@ -93,12 +93,30 @@ static const struct simple_mfd_data maxim_mon_max77705 = {
>  	.mfd_cell_size = ARRAY_SIZE(max77705_sensor_cells),
>  };
>  
> +
> +static const struct regmap_config spacemit_p1_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +};
> +
> +static const struct mfd_cell spacemit_p1_cells[] = {
> +	{ .name = "spacemit-p1-regulator", },
> +	{ .name = "spacemit-p1-rtc", },
> +};
> +
> +static const struct simple_mfd_data spacemit_p1 = {
> +	.regmap_config = &spacemit_p1_regmap_config,
> +	.mfd_cell = spacemit_p1_cells,
> +	.mfd_cell_size = ARRAY_SIZE(spacemit_p1_cells),
> +};
> +
>  static const struct of_device_id simple_mfd_i2c_of_match[] = {
>  	{ .compatible = "kontron,sl28cpld" },
>  	{ .compatible = "silergy,sy7636a", .data = &silergy_sy7636a},
>  	{ .compatible = "maxim,max5970", .data = &maxim_max5970},
>  	{ .compatible = "maxim,max5978", .data = &maxim_max5970},
>  	{ .compatible = "maxim,max77705-battery", .data = &maxim_mon_max77705},
> +	{ .compatible = "spacemit,p1", .data = &spacemit_p1, },
>  	{}
>  };
>  MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);
> -- 
> 2.48.1
> 
> 
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv

Re: [PATCH v12 2/7] mfd: simple-mfd-i2c: add SpacemiT P1 support

[Alex Elder]

On 8/14/25 9:28 PM, Troy Mitchell wrote:
> Hi, Alex,
> 
> I did not find any accesses to the P1 shutdown or reboot registers here.
> Does this mean that the current series does not support reboot or shutdown?

Yes, that is correct.

> If so, do you have any plans to support this functionality?

At this time I personally don't have any plans to add this, but
it could be added later (by anyone).

I actually attempted to do this initially, but gave up.  The PMIC
is accessed via I2C, and I needed to implement a non-blocking
version of the I2C register write operation.  I tried that, but
then found that the shutdown or reboot still did not work reliably.
As it was, this was more than I originally planned to do, so I just
implemented the simple RTC operations instead.

					-Alex

> If I have misunderstood, please correct me.
> 
> Best regards,
> Troy
> 
> 
> On Tue, Aug 12, 2025 at 09:45:03PM -0500, Alex Elder wrote:
>> Enable support for the RTC and regulators found in the SpacemiT P1
>> PMIC.  Support is implemented by the simple I2C MFD driver.
>>
>> The P1 PMIC is normally implemented with the SpacemiT K1 SoC.  This
>> PMIC provides 6 buck converters and 12 LDO regulators.  It also
>> implements a switch, watchdog timer, real-time clock, and more.
>> Initially its RTC and regulators are supported.
>>
>> Signed-off-by: Alex Elder <elder@riscstar.com>
>> ---
>>   drivers/mfd/Kconfig          | 11 +++++++++++
>>   drivers/mfd/simple-mfd-i2c.c | 18 ++++++++++++++++++
>>   2 files changed, 29 insertions(+)
>>
>> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
>> index 425c5fba6cb1e..4d6a5a3a27220 100644
>> --- a/drivers/mfd/Kconfig
>> +++ b/drivers/mfd/Kconfig
>> @@ -1238,6 +1238,17 @@ config MFD_QCOM_RPM
>>   	  Say M here if you want to include support for the Qualcomm RPM as a
>>   	  module. This will build a module called "qcom_rpm".
>>   
>> +config MFD_SPACEMIT_P1
>> +	tristate "SpacemiT P1 PMIC"
>> +	depends on I2C
>> +	select MFD_SIMPLE_MFD_I2C
>> +	help
>> +	  This option supports the I2C-based SpacemiT P1 PMIC, which
>> +	  contains regulators, a power switch, GPIOs, an RTC, and more.
>> +	  This option is selected when any of the supported sub-devices
>> +	  is configured.  The basic functionality is implemented by the
>> +	  simple MFD I2C driver.
>> +
>>   config MFD_SPMI_PMIC
>>   	tristate "Qualcomm SPMI PMICs"
>>   	depends on ARCH_QCOM || COMPILE_TEST
>> diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
>> index 22159913bea03..47ffaac035cae 100644
>> --- a/drivers/mfd/simple-mfd-i2c.c
>> +++ b/drivers/mfd/simple-mfd-i2c.c
>> @@ -93,12 +93,30 @@ static const struct simple_mfd_data maxim_mon_max77705 = {
>>   	.mfd_cell_size = ARRAY_SIZE(max77705_sensor_cells),
>>   };
>>   
>> +
>> +static const struct regmap_config spacemit_p1_regmap_config = {
>> +	.reg_bits = 8,
>> +	.val_bits = 8,
>> +};
>> +
>> +static const struct mfd_cell spacemit_p1_cells[] = {
>> +	{ .name = "spacemit-p1-regulator", },
>> +	{ .name = "spacemit-p1-rtc", },
>> +};
>> +
>> +static const struct simple_mfd_data spacemit_p1 = {
>> +	.regmap_config = &spacemit_p1_regmap_config,
>> +	.mfd_cell = spacemit_p1_cells,
>> +	.mfd_cell_size = ARRAY_SIZE(spacemit_p1_cells),
>> +};
>> +
>>   static const struct of_device_id simple_mfd_i2c_of_match[] = {
>>   	{ .compatible = "kontron,sl28cpld" },
>>   	{ .compatible = "silergy,sy7636a", .data = &silergy_sy7636a},
>>   	{ .compatible = "maxim,max5970", .data = &maxim_max5970},
>>   	{ .compatible = "maxim,max5978", .data = &maxim_max5970},
>>   	{ .compatible = "maxim,max77705-battery", .data = &maxim_mon_max77705},
>> +	{ .compatible = "spacemit,p1", .data = &spacemit_p1, },
>>   	{}
>>   };
>>   MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);
>> -- 
>> 2.48.1
>>
>>
>> _______________________________________________
>> linux-riscv mailing list
>> linux-riscv@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-riscv

Re: [PATCH v12 2/7] mfd: simple-mfd-i2c: add SpacemiT P1 support

[Troy Mitchell]

On Mon, Aug 25, 2025 at 11:08:45AM -0500, Alex Elder wrote:
> On 8/14/25 9:28 PM, Troy Mitchell wrote:
> > Hi, Alex,
> > 
> > I did not find any accesses to the P1 shutdown or reboot registers here.
> > Does this mean that the current series does not support reboot or shutdown?
> 
> Yes, that is correct.
> 
> > If so, do you have any plans to support this functionality?
> 
> At this time I personally don't have any plans to add this, but
> it could be added later (by anyone).
> 
> I actually attempted to do this initially, but gave up.  The PMIC
> is accessed via I2C, and I needed to implement a non-blocking
> version of the I2C register write operation.  I tried that,
You tried that? so that means you have implemented a non-blocking version
of the I2C?
If so, can you give me a source tree to test it?
> but
> then found that the shutdown or reboot still did not work reliably.
ditto.

                - Troy

> As it was, this was more than I originally planned to do, so I just
> implemented the simple RTC operations instead.
> 
> 					-Alex
> 
> > If I have misunderstood, please correct me.
> > 
> > Best regards,
> > Troy
> > 
> > 
> > On Tue, Aug 12, 2025 at 09:45:03PM -0500, Alex Elder wrote:
> > > Enable support for the RTC and regulators found in the SpacemiT P1
> > > PMIC.  Support is implemented by the simple I2C MFD driver.
> > > 
> > > The P1 PMIC is normally implemented with the SpacemiT K1 SoC.  This
> > > PMIC provides 6 buck converters and 12 LDO regulators.  It also
> > > implements a switch, watchdog timer, real-time clock, and more.
> > > Initially its RTC and regulators are supported.
> > > 
> > > Signed-off-by: Alex Elder <elder@riscstar.com>
> > > ---
> > >   drivers/mfd/Kconfig          | 11 +++++++++++
> > >   drivers/mfd/simple-mfd-i2c.c | 18 ++++++++++++++++++
> > >   2 files changed, 29 insertions(+)
> > > 
> > > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> > > index 425c5fba6cb1e..4d6a5a3a27220 100644
> > > --- a/drivers/mfd/Kconfig
> > > +++ b/drivers/mfd/Kconfig
> > > @@ -1238,6 +1238,17 @@ config MFD_QCOM_RPM
> > >   	  Say M here if you want to include support for the Qualcomm RPM as a
> > >   	  module. This will build a module called "qcom_rpm".
> > > +config MFD_SPACEMIT_P1
> > > +	tristate "SpacemiT P1 PMIC"
> > > +	depends on I2C
> > > +	select MFD_SIMPLE_MFD_I2C
> > > +	help
> > > +	  This option supports the I2C-based SpacemiT P1 PMIC, which
> > > +	  contains regulators, a power switch, GPIOs, an RTC, and more.
> > > +	  This option is selected when any of the supported sub-devices
> > > +	  is configured.  The basic functionality is implemented by the
> > > +	  simple MFD I2C driver.
> > > +
> > >   config MFD_SPMI_PMIC
> > >   	tristate "Qualcomm SPMI PMICs"
> > >   	depends on ARCH_QCOM || COMPILE_TEST
> > > diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
> > > index 22159913bea03..47ffaac035cae 100644
> > > --- a/drivers/mfd/simple-mfd-i2c.c
> > > +++ b/drivers/mfd/simple-mfd-i2c.c
> > > @@ -93,12 +93,30 @@ static const struct simple_mfd_data maxim_mon_max77705 = {
> > >   	.mfd_cell_size = ARRAY_SIZE(max77705_sensor_cells),
> > >   };
> > > +
> > > +static const struct regmap_config spacemit_p1_regmap_config = {
> > > +	.reg_bits = 8,
> > > +	.val_bits = 8,
> > > +};
> > > +
> > > +static const struct mfd_cell spacemit_p1_cells[] = {
> > > +	{ .name = "spacemit-p1-regulator", },
> > > +	{ .name = "spacemit-p1-rtc", },
> > > +};
> > > +
> > > +static const struct simple_mfd_data spacemit_p1 = {
> > > +	.regmap_config = &spacemit_p1_regmap_config,
> > > +	.mfd_cell = spacemit_p1_cells,
> > > +	.mfd_cell_size = ARRAY_SIZE(spacemit_p1_cells),
> > > +};
> > > +
> > >   static const struct of_device_id simple_mfd_i2c_of_match[] = {
> > >   	{ .compatible = "kontron,sl28cpld" },
> > >   	{ .compatible = "silergy,sy7636a", .data = &silergy_sy7636a},
> > >   	{ .compatible = "maxim,max5970", .data = &maxim_max5970},
> > >   	{ .compatible = "maxim,max5978", .data = &maxim_max5970},
> > >   	{ .compatible = "maxim,max77705-battery", .data = &maxim_mon_max77705},
> > > +	{ .compatible = "spacemit,p1", .data = &spacemit_p1, },
> > >   	{}
> > >   };
> > >   MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);
> > > -- 
> > > 2.48.1
> > > 
> > > 
> > > _______________________________________________
> > > linux-riscv mailing list
> > > linux-riscv@lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/linux-riscv
> 
> 

Re: [PATCH v12 2/7] mfd: simple-mfd-i2c: add SpacemiT P1 support

[Troy Mitchell]

On Mon, Aug 25, 2025 at 11:08:45AM -0500, Alex Elder wrote:
> On 8/14/25 9:28 PM, Troy Mitchell wrote:
> > Hi, Alex,
> > 
> > I did not find any accesses to the P1 shutdown or reboot registers here.
> > Does this mean that the current series does not support reboot or shutdown?
> 
> Yes, that is correct.
> 
> > If so, do you have any plans to support this functionality?
> 
> At this time I personally don't have any plans to add this, but
> it could be added later (by anyone).
> 
> I actually attempted to do this initially, but gave up.  The PMIC
> is accessed via I2C, and I needed to implement a non-blocking
> version of the I2C register write operation.  I tried that, but
I have implemented a non-blocking version of the I2C driver [1]

Link: 
https://lore.kernel.org/all/20250827-k1-i2c-atomic-v1-0-e59bea02d680@linux.spacemit.com/
[1]

                - Troy
> then found that the shutdown or reboot still did not work reliably.
> As it was, this was more than I originally planned to do, so I just
> implemented the simple RTC operations instead.
> 
> 					-Alex
> 
> > If I have misunderstood, please correct me.
> > 
> > Best regards,
> > Troy
> > 
> > 
> > On Tue, Aug 12, 2025 at 09:45:03PM -0500, Alex Elder wrote:
> > > Enable support for the RTC and regulators found in the SpacemiT P1
> > > PMIC.  Support is implemented by the simple I2C MFD driver.
> > > 
> > > The P1 PMIC is normally implemented with the SpacemiT K1 SoC.  This
> > > PMIC provides 6 buck converters and 12 LDO regulators.  It also
> > > implements a switch, watchdog timer, real-time clock, and more.
> > > Initially its RTC and regulators are supported.
> > > 
> > > Signed-off-by: Alex Elder <elder@riscstar.com>
> > > ---
> > >   drivers/mfd/Kconfig          | 11 +++++++++++
> > >   drivers/mfd/simple-mfd-i2c.c | 18 ++++++++++++++++++
> > >   2 files changed, 29 insertions(+)
> > > 
> > > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> > > index 425c5fba6cb1e..4d6a5a3a27220 100644
> > > --- a/drivers/mfd/Kconfig
> > > +++ b/drivers/mfd/Kconfig
> > > @@ -1238,6 +1238,17 @@ config MFD_QCOM_RPM
> > >   	  Say M here if you want to include support for the Qualcomm RPM as a
> > >   	  module. This will build a module called "qcom_rpm".
> > > +config MFD_SPACEMIT_P1
> > > +	tristate "SpacemiT P1 PMIC"
> > > +	depends on I2C
> > > +	select MFD_SIMPLE_MFD_I2C
> > > +	help
> > > +	  This option supports the I2C-based SpacemiT P1 PMIC, which
> > > +	  contains regulators, a power switch, GPIOs, an RTC, and more.
> > > +	  This option is selected when any of the supported sub-devices
> > > +	  is configured.  The basic functionality is implemented by the
> > > +	  simple MFD I2C driver.
> > > +
> > >   config MFD_SPMI_PMIC
> > >   	tristate "Qualcomm SPMI PMICs"
> > >   	depends on ARCH_QCOM || COMPILE_TEST
> > > diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
> > > index 22159913bea03..47ffaac035cae 100644
> > > --- a/drivers/mfd/simple-mfd-i2c.c
> > > +++ b/drivers/mfd/simple-mfd-i2c.c
> > > @@ -93,12 +93,30 @@ static const struct simple_mfd_data maxim_mon_max77705 = {
> > >   	.mfd_cell_size = ARRAY_SIZE(max77705_sensor_cells),
> > >   };
> > > +
> > > +static const struct regmap_config spacemit_p1_regmap_config = {
> > > +	.reg_bits = 8,
> > > +	.val_bits = 8,
> > > +};
> > > +
> > > +static const struct mfd_cell spacemit_p1_cells[] = {
> > > +	{ .name = "spacemit-p1-regulator", },
> > > +	{ .name = "spacemit-p1-rtc", },
> > > +};
> > > +
> > > +static const struct simple_mfd_data spacemit_p1 = {
> > > +	.regmap_config = &spacemit_p1_regmap_config,
> > > +	.mfd_cell = spacemit_p1_cells,
> > > +	.mfd_cell_size = ARRAY_SIZE(spacemit_p1_cells),
> > > +};
> > > +
> > >   static const struct of_device_id simple_mfd_i2c_of_match[] = {
> > >   	{ .compatible = "kontron,sl28cpld" },
> > >   	{ .compatible = "silergy,sy7636a", .data = &silergy_sy7636a},
> > >   	{ .compatible = "maxim,max5970", .data = &maxim_max5970},
> > >   	{ .compatible = "maxim,max5978", .data = &maxim_max5970},
> > >   	{ .compatible = "maxim,max77705-battery", .data = &maxim_mon_max77705},
> > > +	{ .compatible = "spacemit,p1", .data = &spacemit_p1, },
> > >   	{}
> > >   };
> > >   MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match);
> > > -- 
> > > 2.48.1
> > > 
> > > 
> > > _______________________________________________
> > > linux-riscv mailing list
> > > linux-riscv@lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/linux-riscv
> 
> 

[PATCH v12 3/7] regulator: spacemit: support SpacemiT P1 regulators

[Alex Elder]

Add support for the regulators found in the SpacemiT P1 PMIC.  This
PMIC provides 6 buck converters and 12 LDO regulators.

The PMIC is implemented as a multi-function device.  These regulators
are probed based on this driver being named in a MFD cell in the simple
MFD I2C driver.

Signed-off-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
---
 drivers/regulator/Kconfig       |  13 +++
 drivers/regulator/Makefile      |   1 +
 drivers/regulator/spacemit-p1.c | 157 ++++++++++++++++++++++++++++++++
 3 files changed, 171 insertions(+)
 create mode 100644 drivers/regulator/spacemit-p1.c

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index eaa6df1c9f806..3af99bc3a9ece 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -1395,6 +1395,19 @@ config REGULATOR_SLG51000
 	  The SLG51000 is seven compact and customizable low dropout
 	  regulators.
 
+config REGULATOR_SPACEMIT_P1
+	tristate "SpacemiT P1 regulators"
+	depends on ARCH_SPACEMIT || COMPILE_TEST
+	depends on I2C
+	select MFD_SPACEMIT_P1
+	default ARCH_SPACEMIT
+	help
+	  Enable support for regulators implemented by the SpacemiT P1
+	  power controller.  The P1 implements 6 high-efficiency buck
+	  converters and 12 programmable LDO regulators.  To compile this
+	  driver as a module, choose M here.  The module will be called
+	  "spacemit-pmic".
+
 config REGULATOR_STM32_BOOSTER
 	tristate "STMicroelectronics STM32 BOOSTER"
 	depends on ARCH_STM32 || COMPILE_TEST
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index be98b29d6675d..278f5b8d1c7d7 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -162,6 +162,7 @@ obj-$(CONFIG_REGULATOR_S5M8767) += s5m8767.o
 obj-$(CONFIG_REGULATOR_SC2731) += sc2731-regulator.o
 obj-$(CONFIG_REGULATOR_SKY81452) += sky81452-regulator.o
 obj-$(CONFIG_REGULATOR_SLG51000) += slg51000-regulator.o
+obj-$(CONFIG_REGULATOR_SPACEMIT_P1) += spacemit-p1.o
 obj-$(CONFIG_REGULATOR_STM32_BOOSTER) += stm32-booster.o
 obj-$(CONFIG_REGULATOR_STM32_VREFBUF) += stm32-vrefbuf.o
 obj-$(CONFIG_REGULATOR_STM32_PWR) += stm32-pwr.o
diff --git a/drivers/regulator/spacemit-p1.c b/drivers/regulator/spacemit-p1.c
new file mode 100644
index 0000000000000..d437e6738ea1e
--- /dev/null
+++ b/drivers/regulator/spacemit-p1.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for regulators found in the SpacemiT P1 PMIC
+ *
+ * Copyright (C) 2025 by RISCstar Solutions Corporation.  All rights reserved.
+ * Derived from code from SpacemiT.
+ *	Copyright (c) 2023, SPACEMIT Co., Ltd
+ */
+
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/device.h>
+#include <linux/linear_range.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+
+#define MOD_NAME	"spacemit-p1-regulator"
+
+enum p1_regulator_id {
+	P1_BUCK1,
+	P1_BUCK2,
+	P1_BUCK3,
+	P1_BUCK4,
+	P1_BUCK5,
+	P1_BUCK6,
+
+	P1_ALDO1,
+	P1_ALDO2,
+	P1_ALDO3,
+	P1_ALDO4,
+
+	P1_DLDO1,
+	P1_DLDO2,
+	P1_DLDO3,
+	P1_DLDO4,
+	P1_DLDO5,
+	P1_DLDO6,
+	P1_DLDO7,
+};
+
+static const struct regulator_ops p1_regulator_ops = {
+	.list_voltage		= regulator_list_voltage_linear_range,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.set_voltage_time_sel   = regulator_set_voltage_time_sel,
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.is_enabled		= regulator_is_enabled_regmap,
+};
+
+/* Selector value 255 can be used to disable the buck converter on sleep */
+static const struct linear_range p1_buck_ranges[] = {
+	REGULATOR_LINEAR_RANGE(500000, 0, 170, 5000),
+	REGULATOR_LINEAR_RANGE(1375000, 171, 254, 25000),
+};
+
+/* Selector value 0 can be used for suspend */
+static const struct linear_range p1_ldo_ranges[] = {
+	REGULATOR_LINEAR_RANGE(500000, 11, 127, 25000),
+};
+
+/* These define the voltage selector field for buck and LDO regulators */
+#define BUCK_MASK		GENMASK(7, 0)
+#define LDO_MASK		GENMASK(6, 0)
+
+#define P1_ID(_TYPE, _n)	P1_ ## _TYPE ## _n
+#define P1_ENABLE_REG(_off, _n)	((_off) + 3 * ((_n) - 1))
+
+#define P1_REG_DESC(_TYPE, _type, _n, _s, _off, _mask, _nv, _ranges)	\
+	{								\
+		.name			= #_type #_n,			\
+		.supply_name		= _s,				\
+		.of_match		= of_match_ptr(#_type #_n),	\
+		.regulators_node	= of_match_ptr("regulators"),	\
+		.id			= P1_ID(_TYPE, _n),		\
+		.n_voltages		= _nv,				\
+		.ops			= &p1_regulator_ops,		\
+		.owner			= THIS_MODULE,			\
+		.linear_ranges		= _ranges,			\
+		.n_linear_ranges	= ARRAY_SIZE(_ranges),		\
+		.vsel_reg		= P1_ENABLE_REG(_off, _n) + 1,	\
+		.vsel_mask		= _mask,			\
+		.enable_reg		= P1_ENABLE_REG(_off, _n),	\
+		.enable_mask		= BIT(0),			\
+	}
+
+#define P1_BUCK_DESC(_n) \
+	P1_REG_DESC(BUCK, buck, _n, "vcc", 0x47, BUCK_MASK, 254, p1_buck_ranges)
+
+#define P1_ALDO_DESC(_n) \
+	P1_REG_DESC(ALDO, aldo, _n, "vcc", 0x5b, LDO_MASK, 117, p1_ldo_ranges)
+
+#define P1_DLDO_DESC(_n) \
+	P1_REG_DESC(DLDO, dldo, _n, "buck5", 0x67, LDO_MASK, 117, p1_ldo_ranges)
+
+static const struct regulator_desc p1_regulator_desc[] = {
+	P1_BUCK_DESC(1),
+	P1_BUCK_DESC(2),
+	P1_BUCK_DESC(3),
+	P1_BUCK_DESC(4),
+	P1_BUCK_DESC(5),
+	P1_BUCK_DESC(6),
+
+	P1_ALDO_DESC(1),
+	P1_ALDO_DESC(2),
+	P1_ALDO_DESC(3),
+	P1_ALDO_DESC(4),
+
+	P1_DLDO_DESC(1),
+	P1_DLDO_DESC(2),
+	P1_DLDO_DESC(3),
+	P1_DLDO_DESC(4),
+	P1_DLDO_DESC(5),
+	P1_DLDO_DESC(6),
+	P1_DLDO_DESC(7),
+};
+
+static int p1_regulator_probe(struct platform_device *pdev)
+{
+	struct regulator_config config = { };
+	struct device *dev = &pdev->dev;
+	u32 i;
+
+	/*
+	 * The parent device (PMIC) owns the regmap.  Since we don't
+	 * provide one in the config structure, that one will be used.
+	 */
+	config.dev = dev->parent;
+
+	for (i = 0; i < ARRAY_SIZE(p1_regulator_desc); i++) {
+		const struct regulator_desc *desc = &p1_regulator_desc[i];
+		struct regulator_dev *rdev;
+
+		rdev = devm_regulator_register(dev, desc, &config);
+		if (IS_ERR(rdev))
+			return dev_err_probe(dev, PTR_ERR(rdev),
+					     "error registering regulator %s\n",
+					     desc->name);
+	}
+
+	return 0;
+}
+
+static struct platform_driver p1_regulator_driver = {
+	.probe = p1_regulator_probe,
+	.driver = {
+		.name = MOD_NAME,
+	},
+};
+
+module_platform_driver(p1_regulator_driver);
+
+MODULE_DESCRIPTION("SpacemiT P1 regulator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" MOD_NAME);
-- 
2.48.1

[PATCH v12 4/7] rtc: spacemit: support the SpacemiT P1 RTC

[Alex Elder]

Add support for the RTC found in the SpacemiT P1 PMIC.  Initially
only setting and reading the time are supported.

The PMIC is implemented as a multi-function device.  This RTC is
probed based on this driver being named in a MFD cell in the simple
MFD I2C driver.

Signed-off-by: Alex Elder <elder@riscstar.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
 drivers/rtc/Kconfig           |  10 ++
 drivers/rtc/Makefile          |   1 +
 drivers/rtc/rtc-spacemit-p1.c | 167 ++++++++++++++++++++++++++++++++++
 3 files changed, 178 insertions(+)
 create mode 100644 drivers/rtc/rtc-spacemit-p1.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 64f6e9756aff4..31d355b103d43 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -406,6 +406,16 @@ config RTC_DRV_MAX77686
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-max77686.
 
+config RTC_DRV_SPACEMIT_P1
+	tristate "SpacemiT P1 RTC"
+	depends on ARCH_SPACEMIT || COMPILE_TEST
+	select MFD_SPACEMIT_P1
+	default ARCH_SPACEMIT
+	help
+	  Enable support for the RTC function in the SpacemiT P1 PMIC.
+	  This driver can also be built as a module, which will be called
+	  "spacemit-p1-rtc".
+
 config RTC_DRV_NCT3018Y
 	tristate "Nuvoton NCT3018Y"
 	depends on OF
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 789bddfea99d8..f41fdb4fabae9 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -171,6 +171,7 @@ obj-$(CONFIG_RTC_DRV_SD2405AL)	+= rtc-sd2405al.o
 obj-$(CONFIG_RTC_DRV_SD3078)	+= rtc-sd3078.o
 obj-$(CONFIG_RTC_DRV_SH)	+= rtc-sh.o
 obj-$(CONFIG_RTC_DRV_SNVS)	+= rtc-snvs.o
+obj-$(CONFIG_RTC_DRV_SPACEMIT_P1)	+= rtc-spacemit-p1.o
 obj-$(CONFIG_RTC_DRV_SPEAR)	+= rtc-spear.o
 obj-$(CONFIG_RTC_DRV_STARFIRE)	+= rtc-starfire.o
 obj-$(CONFIG_RTC_DRV_STK17TA8)	+= rtc-stk17ta8.o
diff --git a/drivers/rtc/rtc-spacemit-p1.c b/drivers/rtc/rtc-spacemit-p1.c
new file mode 100644
index 0000000000000..43ab62494bb4b
--- /dev/null
+++ b/drivers/rtc/rtc-spacemit-p1.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the RTC found in the SpacemiT P1 PMIC
+ *
+ * Copyright (C) 2025 by RISCstar Solutions Corporation.  All rights reserved.
+ */
+
+#include <linux/bits.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+
+#define MOD_NAME	"spacemit-p1-rtc"
+
+/*
+ * Six consecutive 1-byte registers hold the seconds, minutes, hours,
+ * day-of-month, month, and year (respectively).
+ *
+ * The range of values in these registers is:
+ *    seconds	0-59
+ *    minutes	0-59
+ *    hours	0-59
+ *    day	0-30 (struct tm is 1-31)
+ *    month	0-11
+ *    year	years since 2000 (struct tm is since 1900)
+ *
+ * Note that the day and month must be converted after reading and
+ * before writing.
+ */
+#define RTC_TIME		0x0d	/* Offset of the seconds register */
+
+#define RTC_CTRL		0x1d
+#define RTC_EN		BIT(2)
+
+/* Number of attempts to read a consistent time stamp before giving up */
+#define RTC_READ_TRIES		20	/* At least 1 */
+
+struct p1_rtc {
+	struct regmap *regmap;
+	struct rtc_device *rtc;
+};
+
+/*
+ * The P1 hardware documentation states that the register values are
+ * latched to ensure a consistent time snapshot within the registers,
+ * but these are in fact unstable due to a bug in the hardware design.
+ * So we loop until we get two identical readings.
+ */
+static int p1_rtc_read_time(struct device *dev, struct rtc_time *t)
+{
+	struct p1_rtc *p1 = dev_get_drvdata(dev);
+	struct regmap *regmap = p1->regmap;
+	u32 count = RTC_READ_TRIES;
+	u8 seconds;
+	u8 time[6];
+	int ret;
+
+	if (!regmap_test_bits(regmap, RTC_CTRL, RTC_EN))
+		return -EINVAL;		/* RTC is disabled */
+
+	ret = regmap_bulk_read(regmap, RTC_TIME, time, sizeof(time));
+	if (ret)
+		return ret;
+
+	do {
+		seconds = time[0];
+		ret = regmap_bulk_read(regmap, RTC_TIME, time, sizeof(time));
+		if (ret)
+			return ret;
+	} while (time[0] != seconds && --count);
+
+	if (!count)
+		return -EIO;		/* Unable to get a consistent result */
+
+	t->tm_sec = time[0] & GENMASK(5, 0);
+	t->tm_min = time[1] & GENMASK(5, 0);
+	t->tm_hour = time[2] & GENMASK(4, 0);
+	t->tm_mday = (time[3] & GENMASK(4, 0)) + 1;
+	t->tm_mon = time[4] & GENMASK(3, 0);
+	t->tm_year = (time[5] & GENMASK(5, 0)) + 100;
+
+	return 0;
+}
+
+/*
+ * The P1 hardware documentation states that values in the registers are
+ * latched so when written they represent a consistent time snapshot.
+ * Nevertheless, this is not guaranteed by the implementation, so we must
+ * disable the RTC while updating it.
+ */
+static int p1_rtc_set_time(struct device *dev, struct rtc_time *t)
+{
+	struct p1_rtc *p1 = dev_get_drvdata(dev);
+	struct regmap *regmap = p1->regmap;
+	u8 time[6];
+	int ret;
+
+	time[0] = t->tm_sec;
+	time[1] = t->tm_min;
+	time[2] = t->tm_hour;
+	time[3] = t->tm_mday - 1;
+	time[4] = t->tm_mon;
+	time[5] = t->tm_year - 100;
+
+	/* Disable the RTC to update; re-enable again when done */
+	ret = regmap_clear_bits(regmap, RTC_CTRL, RTC_EN);
+	if (ret)
+		return ret;
+
+	/* If something goes wrong, leave the RTC disabled */
+	ret = regmap_bulk_write(regmap, RTC_TIME, time, sizeof(time));
+	if (ret)
+		return ret;
+
+	return regmap_set_bits(regmap, RTC_CTRL, RTC_EN);
+}
+
+static const struct rtc_class_ops p1_rtc_class_ops = {
+	.read_time = p1_rtc_read_time,
+	.set_time = p1_rtc_set_time,
+};
+
+static int p1_rtc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rtc_device *rtc;
+	struct p1_rtc *p1;
+
+	p1 = devm_kzalloc(dev, sizeof(*p1), GFP_KERNEL);
+	if (!p1)
+		return -ENOMEM;
+	dev_set_drvdata(dev, p1);
+
+	p1->regmap = dev_get_regmap(dev->parent, NULL);
+	if (!p1->regmap)
+		return dev_err_probe(dev, -ENODEV, "failed to get regmap\n");
+
+	rtc = devm_rtc_allocate_device(dev);
+	if (IS_ERR(rtc))
+		return dev_err_probe(dev, PTR_ERR(rtc),
+				     "error allocating device\n");
+	p1->rtc = rtc;
+
+	rtc->ops = &p1_rtc_class_ops;
+	rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+	rtc->range_max = RTC_TIMESTAMP_END_2063;
+
+	clear_bit(RTC_FEATURE_ALARM, rtc->features);
+	clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features);
+
+	return devm_rtc_register_device(rtc);
+}
+
+static struct platform_driver p1_rtc_driver = {
+	.probe = p1_rtc_probe,
+	.driver = {
+		.name = MOD_NAME,
+	},
+};
+
+module_platform_driver(p1_rtc_driver);
+
+MODULE_DESCRIPTION("SpacemiT P1 RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" MOD_NAME);
-- 
2.48.1

[PATCH v12 5/7] riscv: dts: spacemit: enable the i2c8 adapter

[Alex Elder]

Define properties for the I2C adapter that provides access to the
SpacemiT P1 PMIC.  Enable this adapter on the Banana Pi BPI-F3.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts | 12 ++++++++++++
 arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi    |  7 +++++++
 arch/riscv/boot/dts/spacemit/k1.dtsi            | 13 +++++++++++++
 3 files changed, 32 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
index fe22c747c5012..ae9409fe398b2 100644
--- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
+++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
@@ -40,6 +40,18 @@ &emmc {
 	status = "okay";
 };
 
+&i2c8 {
+	pinctrl-0 = <&i2c8_cfg>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	pmic@41 {
+		compatible = "spacemit,p1";
+		reg = <0x41>;
+		interrupts = <64>;
+	};
+};
+
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_2_cfg>;
diff --git a/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi b/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
index 3810557374228..96d7a46d4bf77 100644
--- a/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
@@ -11,6 +11,13 @@
 #define K1_GPIO(x)	(x / 32) (x % 32)
 
 &pinctrl {
+	i2c8_cfg: i2c8-cfg {
+		i2c8-0-pins {
+			pinmux = <K1_PADCONF(93, 0)>,	/* PWR_SCL */
+				 <K1_PADCONF(94, 0)>;	/* PWR_SDA */
+		};
+	};
+
 	uart0_2_cfg: uart0-2-cfg {
 		uart0-2-pins {
 			pinmux = <K1_PADCONF(68, 2)>,
diff --git a/arch/riscv/boot/dts/spacemit/k1.dtsi b/arch/riscv/boot/dts/spacemit/k1.dtsi
index abde8bb07c95c..580f77b5e838a 100644
--- a/arch/riscv/boot/dts/spacemit/k1.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k1.dtsi
@@ -459,6 +459,19 @@ pwm7: pwm@d401bc00 {
 			status = "disabled";
 		};
 
+		i2c8: i2c@d401d800 {
+			compatible = "spacemit,k1-i2c";
+			reg = <0x0 0xd401d800 0x0 0x38>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			clocks = <&syscon_apbc CLK_TWSI8>,
+				 <&syscon_apbc CLK_TWSI8_BUS>;
+			clock-names = "func", "bus";
+			clock-frequency = <400000>;
+			interrupts = <19>;
+			status = "disabled";
+		};
+
 		pinctrl: pinctrl@d401e000 {
 			compatible = "spacemit,k1-pinctrl";
 			reg = <0x0 0xd401e000 0x0 0x400>;
-- 
2.48.1

[PATCH v12 6/7] riscv: dts: spacemit: define fixed regulators

[Alex Elder]

Define the DC power input and the 4v power as fixed supplies in the
Banana Pi BPI-F3.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 .../boot/dts/spacemit/k1-bananapi-f3.dts      | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
index ae9409fe398b2..a11a60b9f369b 100644
--- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
+++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
@@ -28,6 +28,25 @@ led1 {
 			default-state = "on";
 		};
 	};
+
+	reg_dc_in: dc-in-12v {
+		compatible = "regulator-fixed";
+		regulator-name = "dc_in_12v";
+		regulator-min-microvolt = <12000000>;
+		regulator-max-microvolt = <12000000>;
+		regulator-boot-on;
+		regulator-always-on;
+	};
+
+	reg_vcc_4v: vcc-4v {
+		compatible = "regulator-fixed";
+		regulator-name = "vcc_4v";
+		regulator-min-microvolt = <4000000>;
+		regulator-max-microvolt = <4000000>;
+		regulator-boot-on;
+		regulator-always-on;
+		vin-supply = <&reg_dc_in>;
+	};
 };
 
 &emmc {
-- 
2.48.1

[PATCH v12 7/7] riscv: dts: spacemit: define regulator constraints

[Alex Elder]

Define basic constraints for the regulators in the SpacemiT P1 PMIC,
as implemented in the Banana Pi BPI-F3.

Signed-off-by: Alex Elder <elder@riscstar.com>
---
 .../boot/dts/spacemit/k1-bananapi-f3.dts      | 104 ++++++++++++++++++
 1 file changed, 104 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
index a11a60b9f369b..a9a2596a94e89 100644
--- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
+++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
@@ -68,6 +68,110 @@ pmic@41 {
 		compatible = "spacemit,p1";
 		reg = <0x41>;
 		interrupts = <64>;
+		vin-supply = <&reg_vcc_4v>;
+
+		regulators {
+			buck1 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3450000>;
+				regulator-ramp-delay = <5000>;
+				regulator-always-on;
+			};
+
+			buck2 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3450000>;
+				regulator-ramp-delay = <5000>;
+				regulator-always-on;
+			};
+
+			buck3 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <1800000>;
+				regulator-ramp-delay = <5000>;
+				regulator-always-on;
+			};
+
+			buck4 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3300000>;
+				regulator-ramp-delay = <5000>;
+				regulator-always-on;
+			};
+
+			buck5 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3450000>;
+				regulator-ramp-delay = <5000>;
+				regulator-always-on;
+			};
+
+			buck6 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3450000>;
+				regulator-ramp-delay = <5000>;
+				regulator-always-on;
+			};
+
+			aldo1 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+				regulator-boot-on;
+			};
+
+			aldo2 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+			};
+
+			aldo3 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+			};
+
+			aldo4 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+			};
+
+			dldo1 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+				regulator-boot-on;
+			};
+
+			dldo2 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+			};
+
+			dldo3 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+			};
+
+			dldo4 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+				regulator-always-on;
+			};
+
+			dldo5 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+			};
+
+			dldo6 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+				regulator-always-on;
+			};
+
+			dldo7 {
+				regulator-min-microvolt = <500000>;
+				regulator-max-microvolt = <3400000>;
+			};
+		};
 	};
 };
 
-- 
2.48.1