From: Igor Grinberg <grinberg@compulab.co.il>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH v2] usbh/ehci: Increase timeout for enumeration
Date: Wed, 12 Dec 2012 13:40:48 +0200 [thread overview]
Message-ID: <50C86D40.4010906@compulab.co.il> (raw)
In-Reply-To: <50C8543F.8000508@st.com>
On 12/12/12 11:54, Vipin Kumar wrote:
>
>>> + ulong start = get_timer(0);
>>> +
>>> + do {
>>> + ret = usb_get_port_status(dev, i + 1, portsts);
>>> + if (ret< 0) {
>>> + USB_HUB_PRINTF("get_port_status failed\n");
>>> + break;
>>> + }
>>> +
>>> + portstatus = le16_to_cpu(portsts->wPortStatus);
>>> + portchange = le16_to_cpu(portsts->wPortChange);
>>> +
>>> + if ((portchange& USB_PORT_STAT_C_CONNECTION) ==
>>> + (portstatus& USB_PORT_STAT_CONNECTION))
>>
>> I don't know if there is any corner case when the above check
>> will always fail and so it will always wait a maximal delay time.
>> Are those registers that identical, or can there be differences?
>>
>>> + break;
>>> +
>>> + mdelay(100);
>>> + } while (get_timer(start)< CONFIG_SYS_HZ * 10);
>>
>> Is there any justification for the CONFIG_SYS_HZ * 10?
>> I would be much more fine with this patch if there were any
>> (even just test based * 2) reason for that number.
>>
>
> Not really. Just a practical test.
Ok. good. can we please have a comment saying that this value
is based on observations? Thanks!
You can add my ack along with the comment in v3.
Thanks for the patch!
--
Regards,
Igor.
next prev parent reply other threads:[~2012-12-12 11:40 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-07 8:58 [U-Boot] [PATCH v2] usbh/ehci: Increase timeout for enumeration Vipin Kumar
2012-12-07 10:03 ` Igor Grinberg
2012-12-07 10:18 ` Igor Grinberg
2012-12-07 10:32 ` Vipin Kumar
2012-12-12 9:54 ` Vipin Kumar
2012-12-12 11:25 ` Marek Vasut
2012-12-13 6:11 ` Vipin Kumar
2012-12-12 11:40 ` Igor Grinberg [this message]
2012-12-12 12:00 ` Vipin Kumar
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