diff mbox

[v4,4/9] power: reset: Add AT91RM9200 reset driver

Message ID 1425570594-13124-5-git-send-email-alexandre.belloni@free-electrons.com (mailing list archive)
State New, archived
Headers show

Commit Message

Alexandre Belloni March 5, 2015, 3:49 p.m. UTC 
AT91RM9200 uses the watchdog from the system timer to reset.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 drivers/power/reset/Kconfig            |  7 ++++
 drivers/power/reset/Makefile           |  1 +
 drivers/power/reset/at91rm9200-reset.c | 72 ++++++++++++++++++++++++++++++++++
 3 files changed, 80 insertions(+)
 create mode 100644 drivers/power/reset/at91rm9200-reset.c

Comments

Paul Bolle March 5, 2015, 7:49 p.m. UTC | #1 
On Thu, 2015-03-05 at 16:49 +0100, Alexandre Belloni wrote:
> --- a/drivers/power/reset/Kconfig
> +++ b/drivers/power/reset/Kconfig
> @@ -30,6 +30,13 @@ config POWER_RESET_AT91_RESET
>  	  This driver supports restart for Atmel AT91SAM9 and SAMA5
>  	  SoCs
>  
> +config POWER_RESET_AT91RM9200_RESET
> +	bool "Atmel AT91RM9200 reset driver"

This adds a bool symbol.

> +	depends on ARCH_AT91 && MFD_SYSCON
> +	default SOC_AT91RM9200
> +	help
> +	  This driver supports restart for Atmel AT91RM9200.
> +
>  config POWER_RESET_AXXIA
>  	bool "LSI Axxia reset driver"
>  	depends on ARCH_AXXIA
> diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
> index 11de15bae52e..96e972bbb922 100644
> --- a/drivers/power/reset/Makefile
> +++ b/drivers/power/reset/Makefile
> @@ -1,6 +1,7 @@
>  obj-$(CONFIG_POWER_RESET_AS3722) += as3722-poweroff.o
>  obj-$(CONFIG_POWER_RESET_AT91_POWEROFF) += at91-poweroff.o
>  obj-$(CONFIG_POWER_RESET_AT91_RESET) += at91-reset.o
> +obj-$(CONFIG_POWER_RESET_AT91RM9200_RESET) += at91rm9200-reset.o

This objectfile will never be modular.

>  obj-$(CONFIG_POWER_RESET_AXXIA) += axxia-reset.o
>  obj-$(CONFIG_POWER_RESET_BRCMSTB) += brcmstb-reboot.o
>  obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
> diff --git a/drivers/power/reset/at91rm9200-reset.c b/drivers/power/reset/at91rm9200-reset.c
> new file mode 100644
> index 000000000000..b739ac82b9c9
> --- /dev/null
> +++ b/drivers/power/reset/at91rm9200-reset.c
> @@ -0,0 +1,72 @@

> +#include <linux/module.h>

Is this needed?

> +static struct platform_driver at91rm9200_reset_driver = {
> +	.probe = at91rm9200_reset_probe,
> +	.driver = {
> +		.name = "at91rm9200-reset",
> +		.of_match_table = at91rm9200_reset_of_match,
> +	},
> +};
> +module_platform_driver(at91rm9200_reset_driver);

This should, perhaps, be replaced by a wrapper that calls
    platform_driver_register(at91rm9200_reset_driver)

while that wrapper is, well, called through
    device_initcall()

or something similar. I didn't test this suggestion.

> +MODULE_ALIAS("platform:at91rm9200-reset");
> +MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
> +MODULE_DESCRIPTION("Atmel at91rm9200 System Timer Reset driver");
> +MODULE_LICENSE("GPL v2");

All these macros will be, basically, preprocessed away.


Paul Bolle
Alexandre Belloni March 5, 2015, 8:34 p.m. UTC | #2 
On 05/03/2015 at 20:49:14 +0100, Paul Bolle wrote :
> On Thu, 2015-03-05 at 16:49 +0100, Alexandre Belloni wrote:
> > --- a/drivers/power/reset/Kconfig
> > +++ b/drivers/power/reset/Kconfig
> > @@ -30,6 +30,13 @@ config POWER_RESET_AT91_RESET
> >  	  This driver supports restart for Atmel AT91SAM9 and SAMA5
> >  	  SoCs
> >  
> > +config POWER_RESET_AT91RM9200_RESET
> > +	bool "Atmel AT91RM9200 reset driver"
> 
> This adds a bool symbol.
> 
> > +	depends on ARCH_AT91 && MFD_SYSCON
> > +	default SOC_AT91RM9200
> > +	help
> > +	  This driver supports restart for Atmel AT91RM9200.
> > +
> >  config POWER_RESET_AXXIA
> >  	bool "LSI Axxia reset driver"
> >  	depends on ARCH_AXXIA
> > diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
> > index 11de15bae52e..96e972bbb922 100644
> > --- a/drivers/power/reset/Makefile
> > +++ b/drivers/power/reset/Makefile
> > @@ -1,6 +1,7 @@
> >  obj-$(CONFIG_POWER_RESET_AS3722) += as3722-poweroff.o
> >  obj-$(CONFIG_POWER_RESET_AT91_POWEROFF) += at91-poweroff.o
> >  obj-$(CONFIG_POWER_RESET_AT91_RESET) += at91-reset.o
> > +obj-$(CONFIG_POWER_RESET_AT91RM9200_RESET) += at91rm9200-reset.o
> 
> This objectfile will never be modular.
> 
> >  obj-$(CONFIG_POWER_RESET_AXXIA) += axxia-reset.o
> >  obj-$(CONFIG_POWER_RESET_BRCMSTB) += brcmstb-reboot.o
> >  obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
> > diff --git a/drivers/power/reset/at91rm9200-reset.c b/drivers/power/reset/at91rm9200-reset.c
> > new file mode 100644
> > index 000000000000..b739ac82b9c9
> > --- /dev/null
> > +++ b/drivers/power/reset/at91rm9200-reset.c
> > @@ -0,0 +1,72 @@
> 
> > +#include <linux/module.h>
> 
> Is this needed?
> 
> > +static struct platform_driver at91rm9200_reset_driver = {
> > +	.probe = at91rm9200_reset_probe,
> > +	.driver = {
> > +		.name = "at91rm9200-reset",
> > +		.of_match_table = at91rm9200_reset_of_match,
> > +	},
> > +};
> > +module_platform_driver(at91rm9200_reset_driver);
> 
> This should, perhaps, be replaced by a wrapper that calls
>     platform_driver_register(at91rm9200_reset_driver)
> 
> while that wrapper is, well, called through
>     device_initcall()
> 
> or something similar. I didn't test this suggestion.
> 
> > +MODULE_ALIAS("platform:at91rm9200-reset");
> > +MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
> > +MODULE_DESCRIPTION("Atmel at91rm9200 System Timer Reset driver");
> > +MODULE_LICENSE("GPL v2");
> 
> All these macros will be, basically, preprocessed away.
> 
> 

Indeed, a lot got cargo culted/copy-pasted. I'll fix it and the
at91-reset driver too.

Thanks!
diff mbox

Patch

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 27f6646731b0..8d79e45ae754 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -30,6 +30,13 @@  config POWER_RESET_AT91_RESET
 	  This driver supports restart for Atmel AT91SAM9 and SAMA5
 	  SoCs
 
+config POWER_RESET_AT91RM9200_RESET
+	bool "Atmel AT91RM9200 reset driver"
+	depends on ARCH_AT91 && MFD_SYSCON
+	default SOC_AT91RM9200
+	help
+	  This driver supports restart for Atmel AT91RM9200.
+
 config POWER_RESET_AXXIA
 	bool "LSI Axxia reset driver"
 	depends on ARCH_AXXIA
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 11de15bae52e..96e972bbb922 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -1,6 +1,7 @@ 
 obj-$(CONFIG_POWER_RESET_AS3722) += as3722-poweroff.o
 obj-$(CONFIG_POWER_RESET_AT91_POWEROFF) += at91-poweroff.o
 obj-$(CONFIG_POWER_RESET_AT91_RESET) += at91-reset.o
+obj-$(CONFIG_POWER_RESET_AT91RM9200_RESET) += at91rm9200-reset.o
 obj-$(CONFIG_POWER_RESET_AXXIA) += axxia-reset.o
 obj-$(CONFIG_POWER_RESET_BRCMSTB) += brcmstb-reboot.o
 obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
diff --git a/drivers/power/reset/at91rm9200-reset.c b/drivers/power/reset/at91rm9200-reset.c
new file mode 100644
index 000000000000..b739ac82b9c9
--- /dev/null
+++ b/drivers/power/reset/at91rm9200-reset.c
@@ -0,0 +1,72 @@ 
+/*
+ * Atmel AT91 RM9200 SoCs reset code
+ *
+ * Copyright (C) 2015 Atmel Corporation.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/atmel-st.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+
+static struct regmap *regmap_st;
+
+static int at91rm9200_restart(struct notifier_block *this,
+					unsigned long mode, void *cmd)
+{
+	/*
+	 * Perform a hardware reset with the use of the Watchdog timer.
+	 */
+	regmap_write(regmap_st, AT91_ST_WDMR,
+		     AT91_ST_RSTEN | AT91_ST_EXTEN | 1);
+	regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
+
+	mdelay(2000);
+
+	pr_emerg("Unable to restart system\n");
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block at91rm9200_restart_nb = {
+	.notifier_call = at91rm9200_restart,
+	.priority = 192,
+};
+
+static int at91rm9200_reset_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+
+	regmap_st = syscon_node_to_regmap(np);
+	if (!regmap_st)
+		return -ENODEV;
+
+	return register_restart_handler(&at91rm9200_restart_nb);
+}
+
+static const struct of_device_id at91rm9200_reset_of_match[] = {
+	{ .compatible = "atmel,at91rm9200-st" },
+	{ /* sentinel */ }
+};
+
+static struct platform_driver at91rm9200_reset_driver = {
+	.probe = at91rm9200_reset_probe,
+	.driver = {
+		.name = "at91rm9200-reset",
+		.of_match_table = at91rm9200_reset_of_match,
+	},
+};
+module_platform_driver(at91rm9200_reset_driver);
+
+MODULE_ALIAS("platform:at91rm9200-reset");
+MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
+MODULE_DESCRIPTION("Atmel at91rm9200 System Timer Reset driver");
+MODULE_LICENSE("GPL v2");