[PATCH v2 0/4] BeagleV Starlight reset support

[PATCH v2 0/4] BeagleV Starlight reset support

[Emil Renner Berthing]

This series adds reset support to the BeagleV Starlight board[1], and
converts the TPS65086 PMIC device tree binding to YAML while at it.

Support for the StarFive JH7100 RISC-V SoC on the board is not yet
upstreamed, but is actively worked on so it should only be a matter of
time before that happens.

v2:
- Use generic node name in dt example, tps65086@5e -> pmic@5e.
- Andrew F. Davis' email address no longer works and noone else has
  stepped up, so add myself as dt binding maintainer since I at least
  care that it isn't removed.
- Change the mfd cell name from tps65086-restart to tps65086-reset.
- Split adding the mfd cell name to the mfd driver into its own patch.
- Add Rob and Sebastian's acks to the relevant patches.

[1] https://github.com/beagleboard/beaglev-starlight

Emil Renner Berthing (4):
  dt-bindings: mfd: convert tps65086.txt to YAML
  mfd: tps65086: Make interrupt line optional
  power: reset: Add TPS65086 restart driver
  mfd: tps65086: Add cell entry for reset driver

 .../devicetree/bindings/mfd/ti,tps65086.yaml  | 124 ++++++++++++++++++
 .../devicetree/bindings/mfd/tps65086.txt      |  54 --------
 drivers/mfd/tps65086.c                        |  22 ++--
 drivers/power/reset/Kconfig                   |   6 +
 drivers/power/reset/Makefile                  |   1 +
 drivers/power/reset/tps65086-restart.c        |  98 ++++++++++++++
 6 files changed, 241 insertions(+), 64 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
 delete mode 100644 Documentation/devicetree/bindings/mfd/tps65086.txt
 create mode 100644 drivers/power/reset/tps65086-restart.c

-- 
2.32.0

[PATCH v2 1/4] dt-bindings: mfd: convert tps65086.txt to YAML

[Emil Renner Berthing]

This converts the tps65086.txt binding description to YAML schema so
dts files can be verified automatically.

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
---
 .../devicetree/bindings/mfd/ti,tps65086.yaml  | 127 ++++++++++++++++++
 .../devicetree/bindings/mfd/tps65086.txt      |  54 --------
 2 files changed, 127 insertions(+), 54 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
 delete mode 100644 Documentation/devicetree/bindings/mfd/tps65086.txt

diff --git a/Documentation/devicetree/bindings/mfd/ti,tps65086.yaml b/Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
new file mode 100644
index 000000000000..9f6e1349eadc
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
@@ -0,0 +1,127 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/ti,tps65086.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: TPS65086 Power Management Integrated Circuit (PMIC)
+
+maintainers:
+  - Emil Renner Berthing <kernel@esmil.dk>
+
+properties:
+  compatible:
+    const: ti,tps65086
+
+  reg:
+    const: 0x5e
+    description: I2C slave address
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-controller: true
+
+  '#interrupt-cells':
+    const: 2
+    description: |
+      The first cell is the IRQ number. The second cell is the flags,
+      encoded as trigger masks from ../interrupt-controller/interrupts.txt.
+
+  gpio-controller: true
+
+  '#gpio-cells':
+    const: 2
+    description: |
+      The first cell is the pin number and the second cell is used to specify
+      flags.  See ../gpio/gpio.txt for more information.
+
+  regulators:
+    type: object
+    description: |
+      List of child nodes that specify the regulator initialization data.
+      Child nodes must be named after their hardware counterparts:
+      buck[1-6], ldoa[1-3], swa1, swb[1-2], and vtt.
+      Each child node is defined using the standard binding for regulators and
+      the optional regulator properties defined below.
+
+    patternProperties:
+      "^buck[1-6]$":
+        type: object
+        $ref: ../regulator/regulator.yaml
+
+        properties:
+          regulator-name: true
+          regulator-boot-on: true
+          regulator-always-on: true
+          regulator-min-microvolt: true
+          regulator-max-microvolt: true
+          ti,regulator-step-size-25mv:
+            type: boolean
+            description: |
+              Set this if the regulator is factory set with a 25mv step voltage
+              mapping.
+          ti,regulator-decay:
+            type: boolean
+            description: |
+              Set this if the output needs to decay, default is for the output
+              to slew down.
+
+        additionalProperties: false
+
+      "^(ldoa[1-3]|swa1|swb[1-2]|vtt)$":
+        type: object
+        $ref: ../regulator/regulator.yaml
+
+        properties:
+          regulator-name: true
+          regulator-boot-on: true
+          regulator-always-on: true
+          regulator-min-microvolt: true
+          regulator-max-microvolt: true
+
+        additionalProperties: false
+
+additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-controller
+  - '#interrupt-cells'
+  - gpio-controller
+  - '#gpio-cells'
+  - regulators
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    i2c0 {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        pmic: pmic@5e {
+            compatible = "ti,tps65086";
+            reg = <0x5e>;
+            interrupt-parent = <&gpio1>;
+            interrupts = <28 IRQ_TYPE_LEVEL_LOW>;
+            interrupt-controller;
+            #interrupt-cells = <2>;
+            gpio-controller;
+            #gpio-cells = <2>;
+
+            regulators {
+                buck1 {
+                    regulator-name = "vcc1";
+                    regulator-min-microvolt = <1600000>;
+                    regulator-max-microvolt = <1600000>;
+                    regulator-boot-on;
+                    ti,regulator-decay;
+                    ti,regulator-step-size-25mv;
+                };
+            };
+        };
+    };
+
+...
diff --git a/Documentation/devicetree/bindings/mfd/tps65086.txt b/Documentation/devicetree/bindings/mfd/tps65086.txt
deleted file mode 100644
index 67eac0ed32df..000000000000
--- a/Documentation/devicetree/bindings/mfd/tps65086.txt
+++ /dev/null
@@ -1,54 +0,0 @@
-* TPS65086 Power Management Integrated Circuit (PMIC) bindings
-
-Required properties:
- - compatible		: Should be "ti,tps65086".
- - reg			: I2C slave address.
- - interrupts		: The interrupt line the device is connected to.
- - interrupt-controller	: Marks the device node as an interrupt controller.
- - #interrupt-cells	: The number of cells to describe an IRQ, should be 2.
-			    The first cell is the IRQ number.
-			    The second cell is the flags, encoded as trigger
-			    masks from ../interrupt-controller/interrupts.txt.
- - gpio-controller      : Marks the device node as a GPIO Controller.
- - #gpio-cells          : Should be two.  The first cell is the pin number and
-                            the second cell is used to specify flags.
-                            See ../gpio/gpio.txt for more information.
- - regulators:          : List of child nodes that specify the regulator
-                            initialization data. Child nodes must be named
-                            after their hardware counterparts: buck[1-6],
-                            ldoa[1-3], swa1, swb[1-2], and vtt. Each child
-                            node is defined using the standard binding for
-                            regulators and the optional regulator properties
-                            defined below.
-
-Optional regulator properties:
- - ti,regulator-step-size-25mv	: This is applicable for buck[1-6], set this
-				    if the regulator is factory set with a 25mv
-				    step voltage mapping.
- - ti,regulator-decay		: This is applicable for buck[1-6], set this if
-				    the output needs to decay, default is for
-				    the output to slew down.
-
-Example:
-
-	pmic: tps65086@5e {
-		compatible = "ti,tps65086";
-		reg = <0x5e>;
-		interrupt-parent = <&gpio1>;
-		interrupts = <28 IRQ_TYPE_LEVEL_LOW>;
-		interrupt-controller;
-		#interrupt-cells = <2>;
-		gpio-controller;
-		#gpio-cells = <2>;
-
-		regulators {
-			buck1 {
-				regulator-name = "vcc1";
-				regulator-min-microvolt = <1600000>;
-				regulator-max-microvolt = <1600000>;
-				regulator-boot-on;
-				ti,regulator-decay;
-				ti,regulator-step-size-25mv;
-			};
-		};
-	};
-- 
2.32.0

Re: [PATCH v2 1/4] dt-bindings: mfd: convert tps65086.txt to YAML

[Rob Herring]

On Tue, 27 Jul 2021 11:25:51 +0200, Emil Renner Berthing wrote:
> This converts the tps65086.txt binding description to YAML schema so
> dts files can be verified automatically.
> 
> Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
> ---
>  .../devicetree/bindings/mfd/ti,tps65086.yaml  | 127 ++++++++++++++++++
>  .../devicetree/bindings/mfd/tps65086.txt      |  54 --------
>  2 files changed, 127 insertions(+), 54 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
>  delete mode 100644 Documentation/devicetree/bindings/mfd/tps65086.txt
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v2 1/4] dt-bindings: mfd: convert tps65086.txt to YAML

[Lee Jones]

On Tue, 27 Jul 2021, Emil Renner Berthing wrote:

> This converts the tps65086.txt binding description to YAML schema so
> dts files can be verified automatically.
> 
> Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
> ---
>  .../devicetree/bindings/mfd/ti,tps65086.yaml  | 127 ++++++++++++++++++
>  .../devicetree/bindings/mfd/tps65086.txt      |  54 --------
>  2 files changed, 127 insertions(+), 54 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
>  delete mode 100644 Documentation/devicetree/bindings/mfd/tps65086.txt

Applied, thanks.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH v2 2/4] mfd: tps65086: Make interrupt line optional

[Emil Renner Berthing]

The BeagleV Starlight v0.9 board[1] doesn't have the IRQB line routed to
the SoC, but it is still useful to be able to reach the PMIC over I2C
for the other functionality it provides such as GPIOs and regulator
settings.

[1] https://github.com/beagleboard/beaglev-starlight

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Acked-by: Rob Herring <robh@kernel.org>
Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>
---
 .../devicetree/bindings/mfd/ti,tps65086.yaml  |  3 ---
 drivers/mfd/tps65086.c                        | 21 ++++++++++---------
 2 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/Documentation/devicetree/bindings/mfd/ti,tps65086.yaml b/Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
index 9f6e1349eadc..6aeedda3be15 100644
--- a/Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
+++ b/Documentation/devicetree/bindings/mfd/ti,tps65086.yaml
@@ -87,9 +87,6 @@ additionalProperties: false
 required:
   - compatible
   - reg
-  - interrupts
-  - interrupt-controller
-  - '#interrupt-cells'
   - gpio-controller
   - '#gpio-cells'
   - regulators
diff --git a/drivers/mfd/tps65086.c b/drivers/mfd/tps65086.c
index 341466ef20cc..cc3478ee9a64 100644
--- a/drivers/mfd/tps65086.c
+++ b/drivers/mfd/tps65086.c
@@ -100,29 +100,30 @@ static int tps65086_probe(struct i2c_client *client,
 		 (char)((version & TPS65086_DEVICEID_OTP_MASK) >> 4) + 'A',
 		 (version & TPS65086_DEVICEID_REV_MASK) >> 6);
 
-	ret = regmap_add_irq_chip(tps->regmap, tps->irq, IRQF_ONESHOT, 0,
-				  &tps65086_irq_chip, &tps->irq_data);
-	if (ret) {
-		dev_err(tps->dev, "Failed to register IRQ chip\n");
-		return ret;
+	if (tps->irq > 0) {
+		ret = regmap_add_irq_chip(tps->regmap, tps->irq, IRQF_ONESHOT, 0,
+					  &tps65086_irq_chip, &tps->irq_data);
+		if (ret) {
+			dev_err(tps->dev, "Failed to register IRQ chip\n");
+			return ret;
+		}
 	}
 
 	ret = mfd_add_devices(tps->dev, PLATFORM_DEVID_AUTO, tps65086_cells,
 			      ARRAY_SIZE(tps65086_cells), NULL, 0,
 			      regmap_irq_get_domain(tps->irq_data));
-	if (ret) {
+	if (ret && tps->irq > 0)
 		regmap_del_irq_chip(tps->irq, tps->irq_data);
-		return ret;
-	}
 
-	return 0;
+	return ret;
 }
 
 static int tps65086_remove(struct i2c_client *client)
 {
 	struct tps65086 *tps = i2c_get_clientdata(client);
 
-	regmap_del_irq_chip(tps->irq, tps->irq_data);
+	if (tps->irq > 0)
+		regmap_del_irq_chip(tps->irq, tps->irq_data);
 
 	return 0;
 }
-- 
2.32.0

Re: [PATCH v2 2/4] mfd: tps65086: Make interrupt line optional

[Lee Jones]

On Tue, 27 Jul 2021, Emil Renner Berthing wrote:

> The BeagleV Starlight v0.9 board[1] doesn't have the IRQB line routed to
> the SoC, but it is still useful to be able to reach the PMIC over I2C
> for the other functionality it provides such as GPIOs and regulator
> settings.
> 
> [1] https://github.com/beagleboard/beaglev-starlight
> 
> Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
> Acked-by: Rob Herring <robh@kernel.org>
> Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>
> ---
>  .../devicetree/bindings/mfd/ti,tps65086.yaml  |  3 ---
>  drivers/mfd/tps65086.c                        | 21 ++++++++++---------
>  2 files changed, 11 insertions(+), 13 deletions(-)

Applied, thanks.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH v2 3/4] power: reset: Add TPS65086 restart driver

[Emil Renner Berthing]

The only way to reset the BeagleV Starlight v0.9 board[1] properly is to
tell the PMIC to reset itself which will then assert the external reset
lines of the SoC, USB hub and ethernet phy.

This adds a driver to register a reset handler to do just that.

[1] https://github.com/beagleboard/beaglev-starlight

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
---
 drivers/power/reset/Kconfig            |  6 ++
 drivers/power/reset/Makefile           |  1 +
 drivers/power/reset/tps65086-restart.c | 98 ++++++++++++++++++++++++++
 3 files changed, 105 insertions(+)
 create mode 100644 drivers/power/reset/tps65086-restart.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 4d1192062508..4b563db3ab3e 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -204,6 +204,12 @@ config POWER_RESET_ST
 	help
 	  Reset support for STMicroelectronics boards.
 
+config POWER_RESET_TPS65086
+	bool "TPS65086 restart driver"
+	depends on MFD_TPS65086
+	help
+	  This driver adds support for resetting the TPS65086 PMIC on restart.
+
 config POWER_RESET_VERSATILE
 	bool "ARM Versatile family reboot driver"
 	depends on ARM
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index cf3f4d02d8a5..f606a2f60539 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
 obj-$(CONFIG_POWER_RESET_REGULATOR) += regulator-poweroff.o
 obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
 obj-$(CONFIG_POWER_RESET_ST) += st-poweroff.o
+obj-$(CONFIG_POWER_RESET_TPS65086) += tps65086-restart.o
 obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o
 obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
 obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
diff --git a/drivers/power/reset/tps65086-restart.c b/drivers/power/reset/tps65086-restart.c
new file mode 100644
index 000000000000..78b89f745a3d
--- /dev/null
+++ b/drivers/power/reset/tps65086-restart.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Emil Renner Berthing
+ */
+
+#include <linux/mfd/tps65086.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+
+struct tps65086_restart {
+	struct notifier_block handler;
+	struct device *dev;
+};
+
+static int tps65086_restart_notify(struct notifier_block *this,
+				   unsigned long mode, void *cmd)
+{
+	struct tps65086_restart *tps65086_restart =
+		container_of(this, struct tps65086_restart, handler);
+	struct tps65086 *tps65086 = dev_get_drvdata(tps65086_restart->dev->parent);
+	int ret;
+
+	ret = regmap_write(tps65086->regmap, TPS65086_FORCESHUTDN, 1);
+	if (ret) {
+		dev_err(tps65086_restart->dev, "%s: error writing to tps65086 pmic: %d\n",
+			__func__, ret);
+		return NOTIFY_DONE;
+	}
+
+	/* give it a little time */
+	mdelay(200);
+
+	WARN_ON(1);
+
+	return NOTIFY_DONE;
+}
+
+static int tps65086_restart_probe(struct platform_device *pdev)
+{
+	struct tps65086_restart *tps65086_restart;
+	int ret;
+
+	tps65086_restart = devm_kzalloc(&pdev->dev, sizeof(*tps65086_restart), GFP_KERNEL);
+	if (!tps65086_restart)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, tps65086_restart);
+
+	tps65086_restart->handler.notifier_call = tps65086_restart_notify;
+	tps65086_restart->handler.priority = 192;
+	tps65086_restart->dev = &pdev->dev;
+
+	ret = register_restart_handler(&tps65086_restart->handler);
+	if (ret) {
+		dev_err(&pdev->dev, "%s: cannot register restart handler: %d\n",
+			__func__, ret);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int tps65086_restart_remove(struct platform_device *pdev)
+{
+	struct tps65086_restart *tps65086_restart = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = unregister_restart_handler(&tps65086_restart->handler);
+	if (ret) {
+		dev_err(&pdev->dev, "%s: cannot unregister restart handler: %d\n",
+			__func__, ret);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static const struct platform_device_id tps65086_restart_id_table[] = {
+	{ "tps65086-reset", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, tps65086_restart_id_table);
+
+static struct platform_driver tps65086_restart_driver = {
+	.driver = {
+		.name = "tps65086-restart",
+	},
+	.probe = tps65086_restart_probe,
+	.remove = tps65086_restart_remove,
+	.id_table = tps65086_restart_id_table,
+};
+module_platform_driver(tps65086_restart_driver);
+
+MODULE_AUTHOR("Emil Renner Berthing <kernel@esmil.dk>");
+MODULE_DESCRIPTION("TPS65086 restart driver");
+MODULE_LICENSE("GPL v2");
-- 
2.32.0

Re: [PATCH v2 3/4] power: reset: Add TPS65086 restart driver

[Sebastian Reichel]

[-- Attachment #1: Type: text/plain, Size: 5251 bytes --]

Hi,

On Tue, Jul 27, 2021 at 11:25:53AM +0200, Emil Renner Berthing wrote:
> The only way to reset the BeagleV Starlight v0.9 board[1] properly is to
> tell the PMIC to reset itself which will then assert the external reset
> lines of the SoC, USB hub and ethernet phy.
> 
> This adds a driver to register a reset handler to do just that.
> 
> [1] https://github.com/beagleboard/beaglev-starlight
> 
> Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
> ---

Thanks, queued.

-- Sebastian

>  drivers/power/reset/Kconfig            |  6 ++
>  drivers/power/reset/Makefile           |  1 +
>  drivers/power/reset/tps65086-restart.c | 98 ++++++++++++++++++++++++++
>  3 files changed, 105 insertions(+)
>  create mode 100644 drivers/power/reset/tps65086-restart.c
> 
> diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
> index 4d1192062508..4b563db3ab3e 100644
> --- a/drivers/power/reset/Kconfig
> +++ b/drivers/power/reset/Kconfig
> @@ -204,6 +204,12 @@ config POWER_RESET_ST
>  	help
>  	  Reset support for STMicroelectronics boards.
>  
> +config POWER_RESET_TPS65086
> +	bool "TPS65086 restart driver"
> +	depends on MFD_TPS65086
> +	help
> +	  This driver adds support for resetting the TPS65086 PMIC on restart.
> +
>  config POWER_RESET_VERSATILE
>  	bool "ARM Versatile family reboot driver"
>  	depends on ARM
> diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
> index cf3f4d02d8a5..f606a2f60539 100644
> --- a/drivers/power/reset/Makefile
> +++ b/drivers/power/reset/Makefile
> @@ -23,6 +23,7 @@ obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
>  obj-$(CONFIG_POWER_RESET_REGULATOR) += regulator-poweroff.o
>  obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
>  obj-$(CONFIG_POWER_RESET_ST) += st-poweroff.o
> +obj-$(CONFIG_POWER_RESET_TPS65086) += tps65086-restart.o
>  obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o
>  obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
>  obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o
> diff --git a/drivers/power/reset/tps65086-restart.c b/drivers/power/reset/tps65086-restart.c
> new file mode 100644
> index 000000000000..78b89f745a3d
> --- /dev/null
> +++ b/drivers/power/reset/tps65086-restart.c
> @@ -0,0 +1,98 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2021 Emil Renner Berthing
> + */
> +
> +#include <linux/mfd/tps65086.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/reboot.h>
> +
> +struct tps65086_restart {
> +	struct notifier_block handler;
> +	struct device *dev;
> +};
> +
> +static int tps65086_restart_notify(struct notifier_block *this,
> +				   unsigned long mode, void *cmd)
> +{
> +	struct tps65086_restart *tps65086_restart =
> +		container_of(this, struct tps65086_restart, handler);
> +	struct tps65086 *tps65086 = dev_get_drvdata(tps65086_restart->dev->parent);
> +	int ret;
> +
> +	ret = regmap_write(tps65086->regmap, TPS65086_FORCESHUTDN, 1);
> +	if (ret) {
> +		dev_err(tps65086_restart->dev, "%s: error writing to tps65086 pmic: %d\n",
> +			__func__, ret);
> +		return NOTIFY_DONE;
> +	}
> +
> +	/* give it a little time */
> +	mdelay(200);
> +
> +	WARN_ON(1);
> +
> +	return NOTIFY_DONE;
> +}
> +
> +static int tps65086_restart_probe(struct platform_device *pdev)
> +{
> +	struct tps65086_restart *tps65086_restart;
> +	int ret;
> +
> +	tps65086_restart = devm_kzalloc(&pdev->dev, sizeof(*tps65086_restart), GFP_KERNEL);
> +	if (!tps65086_restart)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, tps65086_restart);
> +
> +	tps65086_restart->handler.notifier_call = tps65086_restart_notify;
> +	tps65086_restart->handler.priority = 192;
> +	tps65086_restart->dev = &pdev->dev;
> +
> +	ret = register_restart_handler(&tps65086_restart->handler);
> +	if (ret) {
> +		dev_err(&pdev->dev, "%s: cannot register restart handler: %d\n",
> +			__func__, ret);
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static int tps65086_restart_remove(struct platform_device *pdev)
> +{
> +	struct tps65086_restart *tps65086_restart = platform_get_drvdata(pdev);
> +	int ret;
> +
> +	ret = unregister_restart_handler(&tps65086_restart->handler);
> +	if (ret) {
> +		dev_err(&pdev->dev, "%s: cannot unregister restart handler: %d\n",
> +			__func__, ret);
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct platform_device_id tps65086_restart_id_table[] = {
> +	{ "tps65086-reset", },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(platform, tps65086_restart_id_table);
> +
> +static struct platform_driver tps65086_restart_driver = {
> +	.driver = {
> +		.name = "tps65086-restart",
> +	},
> +	.probe = tps65086_restart_probe,
> +	.remove = tps65086_restart_remove,
> +	.id_table = tps65086_restart_id_table,
> +};
> +module_platform_driver(tps65086_restart_driver);
> +
> +MODULE_AUTHOR("Emil Renner Berthing <kernel@esmil.dk>");
> +MODULE_DESCRIPTION("TPS65086 restart driver");
> +MODULE_LICENSE("GPL v2");
> -- 
> 2.32.0
> 

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[PATCH v2 4/4] mfd: tps65086: Add cell entry for reset driver

[Emil Renner Berthing]

The only way to reset the BeagleV Starlight v0.9 board[1] properly is to
tell the PMIC to reset itself which will then assert the external reset
lines of the SoC, USB hub and ethernet phy.

This adds an mfd cell entry for the reset driver doing just that.

[1] https://github.com/beagleboard/beaglev-starlight

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
---
 drivers/mfd/tps65086.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/mfd/tps65086.c b/drivers/mfd/tps65086.c
index cc3478ee9a64..3bd5728844a0 100644
--- a/drivers/mfd/tps65086.c
+++ b/drivers/mfd/tps65086.c
@@ -24,6 +24,7 @@
 static const struct mfd_cell tps65086_cells[] = {
 	{ .name = "tps65086-regulator", },
 	{ .name = "tps65086-gpio", },
+	{ .name = "tps65086-reset", },
 };
 
 static const struct regmap_range tps65086_yes_ranges[] = {
-- 
2.32.0

Re: [PATCH v2 4/4] mfd: tps65086: Add cell entry for reset driver

[Lee Jones]

On Tue, 27 Jul 2021, Emil Renner Berthing wrote:

> The only way to reset the BeagleV Starlight v0.9 board[1] properly is to
> tell the PMIC to reset itself which will then assert the external reset
> lines of the SoC, USB hub and ethernet phy.
> 
> This adds an mfd cell entry for the reset driver doing just that.
> 
> [1] https://github.com/beagleboard/beaglev-starlight
> 
> Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
> ---
>  drivers/mfd/tps65086.c | 1 +
>  1 file changed, 1 insertion(+)

Applied, thanks.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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