On 06/13/2012 07:34 AM, Richard Zhao wrote: > Sometimes, boards have gpios that don't own by any driver or owner > by a generic driver that don't like hacks. Such gpios is normally > output and need setup once on boot. So I introduce the config-on-boot > gpios. > > Signed-off-by: Richard Zhao <richard.zhao@xxxxxxxxxxxxx> > Cc: Shawn Guo <shawn.guo@xxxxxxxxxx> > Cc: Rob Herring <rob.herring@xxxxxxxxxxx> > Cc: Grant Likely <grant.likely@xxxxxxxxxxxx> > --- > .../devicetree/bindings/arm/config-on-boot.txt | 12 +++++++ > arch/arm/boot/dts/imx6q-sabrelite.dts | 7 ++++ > arch/arm/mach-imx/mach-imx6q.c | 35 ++++++++++++++++++++ > 3 files changed, 54 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/config-on-boot.txt > > diff --git a/Documentation/devicetree/bindings/arm/config-on-boot.txt b/Documentation/devicetree/bindings/arm/config-on-boot.txt > new file mode 100644 > index 0000000..f98ed74 > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/config-on-boot.txt > @@ -0,0 +1,12 @@ > +* Configure on Boot > + > +Node name: config-on-boot > + It must be in root node. config-on-boot means to describe settings that needs > + to be set one time on boot but aren't owned by any driver, or the owned driver > + is too generic to handle such settings. For example, usb hub uses generic > + driver in usb core code, a on-board usb may need deassert reset pin. NAK. This is not a h/w description and should be solved within the kernel or bootloader. Either fix this in u-boot, the platform code, or make the generic driver support this in a generic way. Rob > + > +Optional properties: > +- output-gpios: Output gpio array that needs to set. > +- output-gpio-values: This property is required if output-gpios is set. > + The value is a array of 0 or 1. Total count eaquals the number of gpios. > diff --git a/arch/arm/boot/dts/imx6q-sabrelite.dts b/arch/arm/boot/dts/imx6q-sabrelite.dts > index e0ec929..1dd2261 100644 > --- a/arch/arm/boot/dts/imx6q-sabrelite.dts > +++ b/arch/arm/boot/dts/imx6q-sabrelite.dts > @@ -17,6 +17,13 @@ > model = "Freescale i.MX6 Quad SABRE Lite Board"; > compatible = "fsl,imx6q-sabrelite", "fsl,imx6q"; > > + config-on-boot { > + output-gpios = < > + &gpio3 22 0>; /* vbus reset */ > + output-gpio-values = < > + 1>; /* vbus reset */ > + }; > + > memory { > reg = <0x10000000 0x40000000>; > }; > diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c > index b47e98b..577cf19 100644 > --- a/arch/arm/mach-imx/mach-imx6q.c > +++ b/arch/arm/mach-imx/mach-imx6q.c > @@ -19,6 +19,7 @@ > #include <linux/irqdomain.h> > #include <linux/of.h> > #include <linux/of_address.h> > +#include <linux/of_gpio.h> > #include <linux/of_irq.h> > #include <linux/of_platform.h> > #include <linux/pinctrl/machine.h> > @@ -113,6 +114,38 @@ static void __init imx6q_sabrelite_init(void) > imx6q_sabrelite_cko1_setup(); > } > > +static void __init imx6q_config_on_boot(void) > +{ > + struct device_node *np; > + struct property *pp; > + int cnt, len, i; > + int gpio; > + > + np = of_find_node_by_path("/config-on-boot"); > + if (!np) > + return; > + cnt = of_gpio_named_count(np, "output-gpios"); > + pp = of_find_property(np, "output-gpio-values", &len); > + if (!pp || cnt != len / sizeof(u32)) { > + pr_err("Invalid config-on-boot gpios!\n"); > + of_node_put(np); > + return; > + } > + for (i = 0; i < cnt; i++) { > + gpio = of_get_named_gpio(np, "output-gpios", i); > + if (gpio_is_valid(gpio)) > + gpio_request_one(gpio, GPIOF_OUT_INIT_HIGH, > + "config-on-boot"); > + } > + > + of_node_put(np); > +} > + > +static void __init imx6q_post_populate(void) > +{ > + imx6q_config_on_boot(); > +} > + > static void __init imx6q_init_machine(void) > { > /* > @@ -126,6 +159,8 @@ static void __init imx6q_init_machine(void) > > of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); > > + imx6q_post_populate(); > + > imx6q_pm_init(); > } > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html