On 2024-02-08 15:10, Shantur Rathore wrote:
On Thu, Feb 8, 2024 at 1:44 PM Dragan Simic <dsi...@manjaro.org> wrote:
On 2024-02-08 14:33, Marek Vasut wrote:
> On 2/8/24 12:30, Shantur Rathore wrote:
>> On Wed, Feb 7, 2024 at 1:07 PM Marek Vasut <ma...@denx.de> wrote:
>>> On 2/7/24 11:23, Shantur Rathore wrote:
>>>> USB 3.0 spec requires hub to reset device while
>>>> enumeration. Some USB 2.0 hubs / devices don't
>>>> handle this well and after implementation of
>>>> reset some USB 2.0 disks weren't detected on
>>>> Allwinner based boards.
>>>>
>>>> Resetting only when hub is USB 3.0 fixes it.
>>>
>>> It would be good to include as many details about the faulty hardware
>>> in
>>> the commit message as possible, so that when someone else runs into
>>> this, they would have all that information available.
>>>
>>>> Tested-by: Andre Przywara <andre.przyw...@arm.com>
>>>>
>>>> Signed-off-by: Shantur Rathore <i...@shantur.com>
>>>> ---
>>>>
>>>> common/usb_hub.c | 6 ++++--
>>>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/common/usb_hub.c b/common/usb_hub.c
>>>> index 3fb7e14d10..2e054eb935 100644
>>>> --- a/common/usb_hub.c
>>>> +++ b/common/usb_hub.c
>>>> @@ -174,8 +174,10 @@ static void usb_hub_power_on(struct
>>>> usb_hub_device *hub)
>>>>
>>>> debug("enabling power on all ports\n");
>>>> for (i = 0; i < dev->maxchild; i++) {
>>>> - usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_RESET);
>>>> - debug("Reset : port %d returns %lX\n", i + 1,
>>>> dev->status);
>>>> + if (usb_hub_is_superspeed(dev)) {
>>>
>>> Should this condition be "all which are lower than superspeed"
>>> instead ,
>>> so when the next generation of USB comes, this problem won't trigger
>>> ?
>>>
>>> What does Linux do btw ?
>>
>> As of now Linux checks if the hub is superspeed
>> https://github.com/torvalds/linux/blob/master/drivers/usb/core/hub.c#L2859
>>
>> which is
>> return hdev->descriptor.bDeviceProtocol == USB_HUB_PR_SS; //
>> USB_HUB_PR_SS = 3
>>
>> This holds true for newer SuperSpeedPlus hubs as well.
>> https://github.com/torvalds/linux/blob/master/drivers/usb/core/hub.h#L155
>>
>> We can change the check to be bDeviceProtocol > 2 but who knows if
>> things change in the newer version of spec.
>> I am open to suggestions.
>
> Please just include the ^ in the commit description. Use link to
> git.kernel.org , not some mirror . This is extremely useful
> information and, well, you already wrote the V2 commit message
> addition in this answer.
Shantur, if that would be easier or quicker for you, I can write
a quite detailed patch description for you, in exchange for a
"Helped-by" tag in the v2 patch submission. :)
That would be really kind of you Dragan.
Sure, I'll write the summary and send it over.
I am down with the flu so that would really help me as my brain is
working at 15% capacity.
Oh, I'm really sorry to hear that. :( I hope you'll get better
soon, and I know very well what's it like; I've also been sick
recently, as a result of some kind of flu that unfortunately found
its way into my lungs, and it took me about a month to get back
to about 90% of my usual mental capacity. I'm still not back to
exactly 100%. :/
I really hope you'll recover much faster.
