[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1469007629-31757-2-git-send-email-peter.chen@nxp.com>
Date: Wed, 20 Jul 2016 17:40:24 +0800
From: Peter Chen <peter.chen@....com>
To: <gregkh@...uxfoundation.org>, <stern@...land.harvard.edu>,
<ulf.hansson@...aro.org>, <broonie@...nel.org>, <sre@...nel.org>,
<robh+dt@...nel.org>, <shawnguo@...nel.org>,
<dbaryshkov@...il.com>, <dwmw2@...radead.org>
CC: <k.kozlowski@...sung.com>, <linux-arm-kernel@...ts.infradead.org>,
<p.zabel@...gutronix.de>, <devicetree@...r.kernel.org>,
<pawel.moll@....com>, <mark.rutland@....com>,
<linux-usb@...r.kernel.org>, <arnd@...db.de>,
<s.hauer@...gutronix.de>, <mail@...iej.szmigiero.name>,
<troy.kisky@...ndarydevices.com>, <festevam@...il.com>,
<oscar@...andei.net>, <stephen.boyd@...aro.org>,
<linux-pm@...r.kernel.org>, <stillcompiling@...il.com>,
<linux-kernel@...r.kernel.org>, Peter Chen <peter.chen@....com>
Subject: [PATCH v3 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library
Add binding doc for generic power sequence library.
Signed-off-by: Peter Chen <peter.chen@....com>
Acked-by: Philipp Zabel <p.zabel@...gutronix.de>
---
.../bindings/power/pwrseq/pwrseq-generic.txt | 48 ++++++++++++++++++++++
1 file changed, 48 insertions(+)
create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
new file mode 100644
index 0000000..48bb3e1
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
@@ -0,0 +1,48 @@
+The generic power sequence library
+
+Some hard-wired devices (eg USB/MMC) need to do power sequence before
+the device can be enumerated on the bus, the typical power sequence
+like: enable USB PHY clock, toggle reset pin, etc. But current
+Linux device driver lacks of such code to do it, it may cause some
+hard-wired devices works abnormal or can't be recognized by
+controller at all. The power sequence will be done before this device
+can be found at the bus.
+
+The power sequence properties is under the device node.
+
+Optional properties:
+- clocks: the input clock for device.
+- reset-gpios: Should specify the GPIO for reset.
+- reset-duration-us: the duration in microsecond for assert reset signal.
+
+Below is the example of USB power sequence properties on USB device
+nodes which have two level USB hubs.
+
+&usbotg1 {
+ vbus-supply = <®_usb_otg1_vbus>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_usb_otg1_id>;
+ status = "okay";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+ genesys: hub@1 {
+ compatible = "usb5e3,608";
+ reg = <1>;
+
+ clocks = <&clks IMX6SX_CLK_CKO>;
+ reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
+ reset-duration-us = <10>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+ asix: ethernet@1 {
+ compatible = "usbb95,1708";
+ reg = <1>;
+
+ clocks = <&clks IMX6SX_CLK_IPG>;
+ reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */
+ reset-duration-us = <15>;
+ };
+ };
+};
--
1.9.1
Powered by blists - more mailing lists