| Message ID | 1352821485-10032-2-git-send-email-andrew@lunn.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Nov 13, 2012 at 4:44 PM, Andrew Lunn <andrew@lunn.ch> wrote: > From: Jamie Lentin <jm@lentin.co.uk> > > Given appropriate devicetree bindings, this driver registers a > pm_power_off function to set a GPIO line high/low to power down > your board. > > Signed-off-by: Jamie Lentin <jm@lentin.co.uk> > Signed-off-by: Andrew Lunn <andrew@lunn.ch> This looks good to me! Acked-by: Linus Walleij <linus.walleij@linaro.org> Yours, Linus Walleij
Hi Andrew, On Tue, Nov 13, 2012 at 04:44:43PM +0100, Andrew Lunn wrote: > From: Jamie Lentin <jm@lentin.co.uk> > > Given appropriate devicetree bindings, this driver registers a > pm_power_off function to set a GPIO line high/low to power down > your board. > > Signed-off-by: Jamie Lentin <jm@lentin.co.uk> > Signed-off-by: Andrew Lunn <andrew@lunn.ch> > --- > .../devicetree/bindings/gpio/gpio-poweroff.txt | 22 ++++ > drivers/power/Kconfig | 3 + > drivers/power/Makefile | 1 + > drivers/power/reset/Kconfig | 15 +++ > drivers/power/reset/Makefile | 1 + > drivers/power/reset/gpio-poweroff.c | 129 ++++++++++++++++++++ > 6 files changed, 171 insertions(+) > create mode 100644 Documentation/devicetree/bindings/gpio/gpio-poweroff.txt > create mode 100644 drivers/power/reset/Kconfig > create mode 100644 drivers/power/reset/Makefile > create mode 100644 drivers/power/reset/gpio-poweroff.c > > diff --git a/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt b/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt > new file mode 100644 > index 0000000..558cdf3 > --- /dev/null > +++ b/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt > @@ -0,0 +1,22 @@ > +GPIO line that should be set high/low to power off a device > + > +Required properties: > +- compatible : should be "gpio-poweroff". > +- gpios : The GPIO to set high/low, see "gpios property" in > + Documentation/devicetree/bindings/gpio/gpio.txt. If the pin should be > + low to power down the board set it to "Active Low", otherwise set > + gpio to "Active High". > + > +Optional properties: > +- input : Initially configure the GPIO line as an input. Only reconfigure > + it to an output when the pm_power_off function is called. If this optional > + property is not specified, the GPIO is initialized as an output in its > + inactive state. > + > + > +Examples: > + > +gpio-poweroff { > + compatible = "gpio-poweroff"; > + gpios = <&gpio 4 0>; /* GPIO 4 Active Low */ > +}; > diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig > index 49a8939..b1d956d 100644 > --- a/drivers/power/Kconfig > +++ b/drivers/power/Kconfig > @@ -335,6 +335,9 @@ config AB8500_BATTERY_THERM_ON_BATCTRL > help > Say Y to enable battery temperature measurements using > thermistor connected on BATCTRL ADC. > + > +source "drivers/power/reset/Kconfig" > + > endif # POWER_SUPPLY > > source "drivers/power/avs/Kconfig" > diff --git a/drivers/power/Makefile b/drivers/power/Makefile > index b949cf8..f1d99f4 100644 > --- a/drivers/power/Makefile > +++ b/drivers/power/Makefile > @@ -49,3 +49,4 @@ obj-$(CONFIG_CHARGER_MAX8997) += max8997_charger.o > obj-$(CONFIG_CHARGER_MAX8998) += max8998_charger.o > obj-$(CONFIG_POWER_AVS) += avs/ > obj-$(CONFIG_CHARGER_SMB347) += smb347-charger.o > +obj-$(CONFIG_POWER_RESET) += reset/ > diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig > new file mode 100644 > index 0000000..6461b48 > --- /dev/null > +++ b/drivers/power/reset/Kconfig > @@ -0,0 +1,15 @@ > +menuconfig POWER_RESET > + bool "Board level reset or power off" > + help > + Provides a number of drivers which either reset a complete board > + or shut it down, by manipulating the main power supply on the board. > + > + Say Y here to enable board reset and power off > + > +config POWER_RESET_GPIO > + bool "GPIO power-off driver" > + depends on OF_GPIO && POWER_RESET > + help > + This driver supports turning off your board via a GPIO line. > + If your board needs a GPIO high/low to power down, say Y and > + create a binding in your devicetree. > diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile > new file mode 100644 > index 0000000..751488a > --- /dev/null > +++ b/drivers/power/reset/Makefile > @@ -0,0 +1 @@ > +obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o > diff --git a/drivers/power/reset/gpio-poweroff.c b/drivers/power/reset/gpio-poweroff.c > new file mode 100644 > index 0000000..101ad57 > --- /dev/null > +++ b/drivers/power/reset/gpio-poweroff.c > @@ -0,0 +1,129 @@ > +/* > + * Toggles a GPIO pin to power down a device > + * > + * Jamie Lentin <jm@lentin.co.uk> > + * Andrew Lunn <andrew@lunn.ch> > + * > + * Copyright (C) 2012 Jamie Lentin > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + */ > +#include <linux/kernel.h> > +#include <linux/init.h> > +#include <linux/delay.h> > +#include <linux/platform_device.h> > +#include <linux/gpio.h> > +#include <linux/of_platform.h> > +#include <linux/of_gpio.h> > +#include <linux/module.h> > + > +/* > + * Hold configuration here, cannot be more than one instance of the driver > + * since pm_power_off itself is global. > + */ > +static int gpio_num = -1; > +static int gpio_active_low; > + > +static void gpio_poweroff_do_poweroff(void) > +{ > + BUG_ON(gpio_num == -1); > + > + /* drive it active */ > + gpio_direction_output(gpio_num, !gpio_active_low); > + mdelay(100); > + /* rising edge or drive inactive */ > + gpio_set_value(gpio_num, gpio_active_low); > + mdelay(100); > + /* falling edge */ > + gpio_set_value(gpio_num, !gpio_active_low); > + > + /* give it some time */ > + mdelay(100); On the IB-NAS 6210 I need to increase this delay to a whopping 3000 milliseconds to suppress the warning (2000 is not enough). Is it acceptable to increase this to such a high value or do we need another solution? > + > + WARN_ON(1); > ... - Simon
> > + * Hold configuration here, cannot be more than one instance of the driver > > + * since pm_power_off itself is global. > > + */ > > +static int gpio_num = -1; > > +static int gpio_active_low; > > + > > +static void gpio_poweroff_do_poweroff(void) > > +{ > > + BUG_ON(gpio_num == -1); > > + > > + /* drive it active */ > > + gpio_direction_output(gpio_num, !gpio_active_low); > > + mdelay(100); > > + /* rising edge or drive inactive */ > > + gpio_set_value(gpio_num, gpio_active_low); > > + mdelay(100); > > + /* falling edge */ > > + gpio_set_value(gpio_num, !gpio_active_low); > > + > > + /* give it some time */ > > + mdelay(100); > > On the IB-NAS 6210 I need to increase this delay to a whopping 3000 > milliseconds to suppress the warning (2000 is not enough). Is it > acceptable to increase this to such a high value or do we need > another solution? Hi Simon It is interesting how slow these things are at turning off. I already had to increase it once from 10ms for the DNSKW. So i will increase it to 3000 in the next spin of the patches. Thanks Andrew
diff --git a/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt b/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt new file mode 100644 index 0000000..558cdf3 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt @@ -0,0 +1,22 @@ +GPIO line that should be set high/low to power off a device + +Required properties: +- compatible : should be "gpio-poweroff". +- gpios : The GPIO to set high/low, see "gpios property" in + Documentation/devicetree/bindings/gpio/gpio.txt. If the pin should be + low to power down the board set it to "Active Low", otherwise set + gpio to "Active High". + +Optional properties: +- input : Initially configure the GPIO line as an input. Only reconfigure + it to an output when the pm_power_off function is called. If this optional + property is not specified, the GPIO is initialized as an output in its + inactive state. + + +Examples: + +gpio-poweroff { + compatible = "gpio-poweroff"; + gpios = <&gpio 4 0>; /* GPIO 4 Active Low */ +}; diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig index 49a8939..b1d956d 100644 --- a/drivers/power/Kconfig +++ b/drivers/power/Kconfig @@ -335,6 +335,9 @@ config AB8500_BATTERY_THERM_ON_BATCTRL help Say Y to enable battery temperature measurements using thermistor connected on BATCTRL ADC. + +source "drivers/power/reset/Kconfig" + endif # POWER_SUPPLY source "drivers/power/avs/Kconfig" diff --git a/drivers/power/Makefile b/drivers/power/Makefile index b949cf8..f1d99f4 100644 --- a/drivers/power/Makefile +++ b/drivers/power/Makefile @@ -49,3 +49,4 @@ obj-$(CONFIG_CHARGER_MAX8997) += max8997_charger.o obj-$(CONFIG_CHARGER_MAX8998) += max8998_charger.o obj-$(CONFIG_POWER_AVS) += avs/ obj-$(CONFIG_CHARGER_SMB347) += smb347-charger.o +obj-$(CONFIG_POWER_RESET) += reset/ diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig new file mode 100644 index 0000000..6461b48 --- /dev/null +++ b/drivers/power/reset/Kconfig @@ -0,0 +1,15 @@ +menuconfig POWER_RESET + bool "Board level reset or power off" + help + Provides a number of drivers which either reset a complete board + or shut it down, by manipulating the main power supply on the board. + + Say Y here to enable board reset and power off + +config POWER_RESET_GPIO + bool "GPIO power-off driver" + depends on OF_GPIO && POWER_RESET + help + This driver supports turning off your board via a GPIO line. + If your board needs a GPIO high/low to power down, say Y and + create a binding in your devicetree. diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile new file mode 100644 index 0000000..751488a --- /dev/null +++ b/drivers/power/reset/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o diff --git a/drivers/power/reset/gpio-poweroff.c b/drivers/power/reset/gpio-poweroff.c new file mode 100644 index 0000000..101ad57 --- /dev/null +++ b/drivers/power/reset/gpio-poweroff.c @@ -0,0 +1,129 @@ +/* + * Toggles a GPIO pin to power down a device + * + * Jamie Lentin <jm@lentin.co.uk> + * Andrew Lunn <andrew@lunn.ch> + * + * Copyright (C) 2012 Jamie Lentin + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/gpio.h> +#include <linux/of_platform.h> +#include <linux/of_gpio.h> +#include <linux/module.h> + +/* + * Hold configuration here, cannot be more than one instance of the driver + * since pm_power_off itself is global. + */ +static int gpio_num = -1; +static int gpio_active_low; + +static void gpio_poweroff_do_poweroff(void) +{ + BUG_ON(gpio_num == -1); + + /* drive it active */ + gpio_direction_output(gpio_num, !gpio_active_low); + mdelay(100); + /* rising edge or drive inactive */ + gpio_set_value(gpio_num, gpio_active_low); + mdelay(100); + /* falling edge */ + gpio_set_value(gpio_num, !gpio_active_low); + + /* give it some time */ + mdelay(100); + + WARN_ON(1); +} + +static int __devinit gpio_poweroff_probe(struct platform_device *pdev) +{ + enum of_gpio_flags flags; + bool input = false; + int ret; + + /* If a pm_power_off function has already been added, leave it alone */ + if (pm_power_off != NULL) { + pr_err("%s: pm_power_off function already registered", + __func__); + return -EBUSY; + } + + gpio_num = of_get_gpio_flags(pdev->dev.of_node, 0, &flags); + if (gpio_num < 0) { + pr_err("%s: Could not get GPIO configuration: %d", + __func__, gpio_num); + return -ENODEV; + } + gpio_active_low = flags & OF_GPIO_ACTIVE_LOW; + + if (of_get_property(pdev->dev.of_node, "input", NULL)) + input = true; + + ret = gpio_request(gpio_num, "poweroff-gpio"); + if (ret) { + pr_err("%s: Could not get GPIO %d", __func__, gpio_num); + return ret; + } + if (input) { + if (gpio_direction_input(gpio_num)) { + pr_err("Could not set direction of GPIO %d to input", + gpio_num); + goto err; + } + } else { + if (gpio_direction_output(gpio_num, gpio_active_low)) { + pr_err("Could not set direction of GPIO %d", gpio_num); + goto err; + } + } + + pm_power_off = &gpio_poweroff_do_poweroff; + return 0; + +err: + gpio_free(gpio_num); + return -ENODEV; +} + +static int __devexit gpio_poweroff_remove(struct platform_device *pdev) +{ + if (gpio_num != -1) + gpio_free(gpio_num); + if (pm_power_off == &gpio_poweroff_do_poweroff) + pm_power_off = NULL; + + return 0; +} + +static const struct of_device_id of_gpio_poweroff_match[] = { + { .compatible = "gpio-poweroff", }, + {}, +}; + +static struct platform_driver gpio_poweroff_driver = { + .probe = gpio_poweroff_probe, + .remove = __devexit_p(gpio_poweroff_remove), + .driver = { + .name = "poweroff-gpio", + .owner = THIS_MODULE, + .of_match_table = of_gpio_poweroff_match, + }, +}; + +module_platform_driver(gpio_poweroff_driver); + +MODULE_AUTHOR("Jamie Lentin <jm@lentin.co.uk>"); +MODULE_DESCRIPTION("GPIO poweroff driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:poweroff-gpio");