Hi Andrew, On Tue, Nov 13, 2012 at 04:44:43PM +0100, Andrew Lunn wrote: > From: Jamie Lentin <[email protected]> > > 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 <[email protected]> > Signed-off-by: Andrew Lunn <[email protected]> > --- > .../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 <[email protected]> > + * Andrew Lunn <[email protected]> > + * > + * 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 _______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
