[PATCH v3 12/12] ARM: dts: exynos: Fix LAN and HUB after bootloader initialization on Odroid U3

Peter Chen hzpeterchen at gmail.com
Thu Jun 2 00:58:44 PDT 2016


On Thu, Jun 02, 2016 at 09:26:57AM +0200, Krzysztof Kozlowski wrote:
> On 06/01/2016 01:59 PM, Peter Chen wrote:
> > On Wed, Jun 01, 2016 at 10:02:21AM +0200, Krzysztof Kozlowski wrote:
> >> On Odroid U3 (Exynos4412-based) board if USB was initialized by
> >> bootloader (in U-Boot "usb start" before tftpboot), the HUB (usb3503)
> >> and LAN (smsc95xx) after after successful probing were not visible in the
> >> system ("lsusb").
> >>
> >> In such case the devices had to be fully reset before configuring.
> >> Reset by GPIO (called RESET_N pin) and by RESET field in STCD register
> >> in usb3503 HUB are not sufficient. Instead full reset has to be done by
> >> disabling and enabling regulator.
> >>
> >> Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
> >> ---
> >>  arch/arm/boot/dts/exynos4412-odroidu3.dts | 4 ++++
> >>  1 file changed, 4 insertions(+)
> >>
> >> diff --git a/arch/arm/boot/dts/exynos4412-odroidu3.dts b/arch/arm/boot/dts/exynos4412-odroidu3.dts
> >> index 31cdc036fda4..23e30e4609df 100644
> >> --- a/arch/arm/boot/dts/exynos4412-odroidu3.dts
> >> +++ b/arch/arm/boot/dts/exynos4412-odroidu3.dts
> >> @@ -99,11 +99,15 @@
> >>  	clock-names = "refclk";
> >>  	clocks = <&pmu_system_controller 0>;
> >>  	refclk-frequency = <24000000>;
> >> +
> >> +	power-sequence;
> >> +	ext-supply = <&buck8_reg>;
> >>  };
> >>  
> >>  &ehci {
> >>  	port at 1 {
> >>  		status = "okay";
> >> +		usb-pwrseq = <&usb3503>;
> >>  	};
> >>  	port at 2 {
> >>  		status = "okay";
> >> -- 
> >> 1.9.1
> >>
> > 
> > The hub is under the port1, you may need to describe it
> > under the port at 1, see below:
> > Documentation/devicetree/bindings/usb/usb-device.txt
> 
> My configuration is a little bit different than yours.
> 
> In my case I have a USB hub (usb3503) which is also a a i2c device
> because it has to be configured through I2C.
> 
> I can add the power-sequence properties to the I2C node or as you
> pointed under port using the vendor-product-id compatible. In the first
> option: not many USB changes are needed. It works for me, at least as a
> proof of concept.
> 
> The second solution: currently it does not work because the USB device
> does not get enumerated before the power sequence begins. It would be
> great if you could implement this on USB side.

Well, not matter which solution, the USB device can't be enumerated
without power sequence. For the #2 solution, it just handles all
gpios under dts before the enumeration at USB code.

> 
> > 
> > If I get Rob's comments correctly, you may need to consider 
> > below MMC and USB device tree description together, it seems
> > hard for USB to use pwrseq driver, sorry for confusing you.
> > 
> > If rob can accept below USB device description, we have to
> > do it under USB. In future, if there is some suitable framework,
> > we can move it.
> > 
> > 1. MMC device:
> > 	usdhc3_pwrseq: usdhc3_pwrseq {
> > 		compatible = "mmc-pwrseq-simple";
> > 		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>, 	/* WL_REG_ON */
> > 			      <&gpio4 7 GPIO_ACTIVE_LOW>, 	/* WL_HOSTWAKE */
> > 			      <&gpio3 25 GPIO_ACTIVE_LOW>, 	/* BT_REG_ON */
> > 			      <&gpio3 27 GPIO_ACTIVE_LOW>,	/* BT_HOSTWAKE */
> > 			      <&gpio4 4 GPIO_ACTIVE_LOW>, 	/* BT_WAKE */
> > 			      <&gpio4 6 GPIO_ACTIVE_LOW>; 	/* BT_RST_N */
> > 	};
> > 
> > &usdhc3 {
> > 	pinctrl-names = "default", "state_100mhz", "state_200mhz";
> > 	pinctrl-0 = <&pinctrl_usdhc3>;
> > 	pinctrl-1 = <&pinctrl_usdhc3_100mhz>;
> > 	pinctrl-2 = <&pinctrl_usdhc3_200mhz>;
> > 	bus-width = <4>;
> > 	non-removable;
> > 	keep-power-in-suspend;
> > 	wakeup-source;
> > 	mmc-pwrseq = <&usdhc3_pwrseq>;
> > 	status = "okay";
> > };
> > 
> > 2. USB device 
> > 
> > &usbotg1 {
> > 	vbus-supply = <&reg_usb_otg1_vbus>;
> > 	pinctrl-names = "default";
> > 	pinctrl-0 = <&pinctrl_usb_otg1_id>;
> > 	status = "okay";
> > 
> > 	#address-cells = <1>;
> > 	#size-cells = <0>;
> > 	hub: genesys at 1 {
> > 		compatible = "usb5e3,608";
> > 		reg = <1>;
> > 		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
> > 		reset-duration-us = <10>;
> > 		clocks = <&clks IMX6SX_CLK_CKO>;
> > 	};
> 
> Yes, that looks like what Rob wanted... Do you plan to work on it? The
> power sequence is needed before device is enumerated.
> 

Ok, I will work on it.

-- 

Best Regards,
Peter Chen



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