On 06/18/2013 05:29 AM, Marek Vasut wrote:
Dear Stephen Warren,
On 06/17/2013 02:39 PM, Marek Vasut wrote:
Dear Thierry Reding,
On Sun, Jun 16, 2013 at 10:48:45PM +0200, Marek Vasut wrote:
Dear Thierry Reding,
On Sat, Jun 15, 2013 at 11:28:25PM +0200, Marek Vasut wrote: > Dear Thierry Reding, > >> On Fri, Jun 14, 2013 at 06:41:40PM +0800, Jim Lin wrote: >> [...] >> >>> diff --git a/board/nvidia/dts/tegra30-beaver.dts >>> b/board/nvidia/dts/tegra30-beaver.dts >> >> [...] >> >>> @@ -68,4 +69,9 @@ >>> >>> status = "okay"; >>> bus-width = <8>; >>> >>> }; >>> >>> + >>> + usb@7d008000 { >>> + nvidia,vbus-gpio = <&gpio 61 3>; /* PH5,
USB13_VBUS_PULLUP */
>> This doesn't work for me on Beaver. I need to turn the above line >> into >> >> this: >> nvidia,vbus-gpio = <&gpio 236 0>; /* PDD4 */ >> >> PDD4 is the correct GPIO according to the schematics and the pin is >> high-active. Also as far as I can tell, 3 is not a meaningful value >> for the U-Boot GPIO bindings. Only the value 1 (low-active) is >> used. >> >> With that change applied on top of your patches I can see that a >> USB flash drive connected to USB3 is indeed powered. However I >> noticed >> >> something strange. When I try to use USB, I get this: >> Tegra30 (Beaver) # usb start >> (Re)start USB... >> USB0: set_host_mode: GPIO 236 high >> USB EHCI 1.00 >> scanning bus 0 for devices... 1 USB Device(s) found >> >> scanning usb for storage devices... 0 Storage Device(s) >> found scanning usb for ethernet devices... 0 Ethernet >> Device(s) found >> >> So no storage device is detected, even though a USB flash drive is >> connected and powered properly. If I repeat the same command, >> however, >> >> the storage device is detected: >> Tegra30 (Beaver) # usb reset >> (Re)start USB... >> USB0: set_host_mode: GPIO 236 high >> USB EHCI 1.00 >> scanning bus 0 for devices... 2 USB Device(s) found >> >> scanning usb for storage devices... 1 Storage Device(s) >> found scanning usb for ethernet devices... 0 Ethernet >> Device(s) found >> >> Any idea what might be going on here? > > Try waiting a little after setting the GPIO maybe? The drive might > need some time to settle.
I can make it work on the first invocation of "usb start" by adding a rather long mdelay() at the very end of ehci_hcd_init() in the Tegra EHCI driver. The magic value seems to be 853 ms. 852 ms wasn't enough in any of the test runs. 853 ms always worked.
However 850+ ms seems like a very long time for the device to settle, and keeping it in the driver probably isn't a good idea. Furthermore I cannot reproduce the same issue with a newer flash drive, which works fine with no additional delays.
Try reverting 020bbcb "usb: hub: Power-cycle on root-hub ports" ... there's a thread in the ML that it caused issues.
I reverted the following two patches: 0bf796f usb: hub: Parallelize power-cycling of root-hub ports 020bbcb usb: hub: Power-cycle on root-hub ports
because it wasn't trivial to revert only 020bbcb alone. However it didn't change anything regarding the problem I was seeing.
Thierry
Ok, this looks ugly and calls for a bisect. Can you check it ? I'll try to test if USB works for me on some EHCI-enabled device.
The problem is definitely caused by 020bbcb "usb: hub: Power-cycle on root-hub ports"; I reverted just that locally and it fixed my problems.
Even this one ? Did we already get any reply from the patch author?
Oh, it's possible this is a different symptom, although I'd wager since it's narrowed down to a patch that's known to cause another problem already, it's the same patch that caused it, but yes that should be verified explicitly.
No, I haven't heard anything at all from the patch author.