diff mbox series

[v1,3/3] power: reset: Add TPS65086 restart driver

Message ID 20210625224744.1020108-4-kernel@esmil.dk
State Superseded
Headers show
Series BeagleV Starlight reset support | expand

Commit Message

Emil Renner Berthing June 25, 2021, 10:47 p.m. UTC 
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>
---
 drivers/mfd/tps65086.c                 |  1 +
 drivers/power/reset/Kconfig            |  6 ++
 drivers/power/reset/Makefile           |  1 +
 drivers/power/reset/tps65086-restart.c | 99 ++++++++++++++++++++++++++
 4 files changed, 107 insertions(+)
 create mode 100644 drivers/power/reset/tps65086-restart.c

Comments

Sebastian Reichel July 20, 2021, 4:12 p.m. UTC | #1 
Hi,

On Sat, Jun 26, 2021 at 12:47:44AM +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>


-- Sebastian

>  drivers/mfd/tps65086.c                 |  1 +

>  drivers/power/reset/Kconfig            |  6 ++

>  drivers/power/reset/Makefile           |  1 +

>  drivers/power/reset/tps65086-restart.c | 99 ++++++++++++++++++++++++++

>  4 files changed, 107 insertions(+)

>  create mode 100644 drivers/power/reset/tps65086-restart.c

> 

> diff --git a/drivers/mfd/tps65086.c b/drivers/mfd/tps65086.c

> index cc3478ee9a64..1bfba0758fcc 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-restart", },

>  };

>  

>  static const struct regmap_range tps65086_yes_ranges[] = {

> 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..ad9f2c5a84ac

> --- /dev/null

> +++ b/drivers/power/reset/tps65086-restart.c

> @@ -0,0 +1,99 @@

> +// 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 tps65086 *tps;

> +	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);

> +	int ret;

> +

> +	ret = regmap_write(tps65086_restart->tps->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->tps = dev_get_drvdata(pdev->dev.parent);

> +	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-restart", },

> +	{ /* 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

>
diff mbox series

Patch

diff --git a/drivers/mfd/tps65086.c b/drivers/mfd/tps65086.c
index cc3478ee9a64..1bfba0758fcc 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-restart", },
 };
 
 static const struct regmap_range tps65086_yes_ranges[] = {
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..ad9f2c5a84ac
--- /dev/null
+++ b/drivers/power/reset/tps65086-restart.c
@@ -0,0 +1,99 @@ 
+// 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 tps65086 *tps;
+	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);
+	int ret;
+
+	ret = regmap_write(tps65086_restart->tps->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->tps = dev_get_drvdata(pdev->dev.parent);
+	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-restart", },
+	{ /* 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");