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 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
