From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [Patch v5 08/13] ARM: imx6q: add config-on-boot gpios Date: Wed, 13 Jun 2012 11:50:35 -0500 Message-ID: <4FD8C4DB.4020908@gmail.com> References: <1339590863-10564-1-git-send-email-richard.zhao@freescale.com> <1339590863-10564-9-git-send-email-richard.zhao@freescale.com> <4FD8AD42.6010702@gmail.com> <20120613152841.GA23590@richard-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120613152841.GA23590@richard-laptop> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Richard Zhao Cc: Richard Zhao , linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, marex-ynQEQJNshbs@public.gmane.org, B20596-KZfg59tc24xl57MIdRCFDg@public.gmane.org, dong.aisheng-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, fabio.estevam-KZfg59tc24xl57MIdRCFDg@public.gmane.org, alexander.shishkin-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, B29397-KZfg59tc24xl57MIdRCFDg@public.gmane.org, balbi-l0cyMroinI0@public.gmane.org, Grant Likely , stern-nwvwT67g6+6dFdvTe/nMLpVzexx5G7lz@public.gmane.org, kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, shawn.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org List-Id: devicetree@vger.kernel.org On 06/13/2012 10:28 AM, Richard Zhao wrote: > On Wed, Jun 13, 2012 at 10:09:54AM -0500, Rob Herring wrote: >> 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 >>> Cc: Shawn Guo >>> Cc: Rob Herring >>> Cc: Grant Likely >>> --- >>> .../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 > It's misc things, but is hw description. You are defining something based on whether linux has a driver or not. That should not matter to DT. That's backwards. >> and should be solved within the >> kernel or bootloader. Either fix this in u-boot, > Kernel might be better not to depend on uboot. >> the platform code, or > How do I get gpio in platfrom code without dts description? >> make the generic driver support this in a generic way. > It's called just after populate devices. It's hard for generic driver to > decide when it's called. You need to describe that you have a hub on the usb bus and add the gpio line to that node. Just like PCI is probe-able, you still need DT nodes sometimes for cases like this. A simpler approach would be to just add the gpio to the ehci controller node, but that's not exactly correct. Rob > > Thanks > Richard >> >> 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 >>> #include >>> #include >>> +#include >>> #include >>> #include >>> #include >>> @@ -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-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html