On 13.06.2012 14:34, 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.z...@freescale.com> Cc: Shawn Guo <shawn....@linaro.org> Cc: Rob Herring <rob.herr...@calxeda.com> Cc: Grant Likely <grant.lik...@secretlab.ca> --- .../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. + +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");
While trying to use this code: Is there a special reason why all pins are set to HIGH here? The contents of 'output-gpio-values' seem to be ignored?
Best regards Dirk -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
