RE: usb hub is n't recognised during boot up(sometimes)

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Hi Peter,

-----Original Message-----
From: Peter Chen [mailto:hzpeterchen@xxxxxxxxx] 
Sent: Monday, July 02, 2012 6:28 PM
To: Alan Stern
Cc: shaiju shaiju; Sadasivan Shaiju; USB list
Subject: Re: usb hub is n't recognised during boot up(sometimes)

Hi Shaiju,

The host controller sends two BUS_RESET during the enumeration,  the first
one
is when the host controller detects there is a port change, the second
one is after
first GET_DESCRIPTOR.
>From your  "dmesg-usb_debug-broke.out", -- see below
It tells us the first BUS_RESET is successful, the line state goes to SE0,
and
PORT_ENABLE is 1. But there is a problem at the second BUS_RESET.

Try to read your hub spec, and there is reset pin usually. Try to
reset it at your
platform code (before usb driver loads).

Where  should I  do  this ?  In  which  function  ?

Is  a  port reset (once)  in hub_port_init()  will be  enough ?

Regards,
Shaiju.

>ehci_hcd 0000:00:1d.0: port 1 high speed
>ehci_hcd 0000:00:1d.0: GetStatus port 1 status 001005 POWER sig=se0 PE
CONNECT
>oprofile: using NMI interrupt.
>nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
>usb 2-1: new high speed USB device using ehci_hcd and address 2
>usb 1-1: link qh256-0001/ffff8801581b2b80 start 1 [1/0 us]
>ehci_hcd 0000:00:1d.0: port 1 full speed --> companion
>ehci_hcd 0000:00:1d.0: GetStatus port 1 status 003801 POWER OWNER sig=j
CONNECT
>hub 2-0:1.0: port 1 not reset yet, waiting 50ms

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