[U-Boot] [PATCH] musb: set MUSB speed based on CONFIG

[Bin Liu]

Hi,

On 07/10/2015 10:12 AM, Heiko Schocher wrote:
> Hello Samuel,
>
> Am 10.07.2015 um 16:50 schrieb Egli, Samuel:
>> Hi Hans,
>>
>>> -----Original Message----- From: Hans de Goede
>>> [mailto:hdegoede at redhat.com] Sent: Freitag, 10. Juli 2015 16:37
>>> To: Egli, Samuel; marex at denx.de Cc: u-boot at lists.denx.de;
>>> trini at konsulko.com; Bin Liu; Meier, Roger; Daniel Mack Subject:
>>> Re: [U-Boot] [PATCH] musb: set MUSB speed based on CONFIG
>>>
>>> Hi,
>>>
>>> On 10-07-15 16:30, Hans de Goede wrote:
>>>> Hi,
>>>>
>>>> On 10-07-15 15:16, Samuel Egli wrote:
>>>>> From: Bin Liu <b-liu at ti.com>
>>>>>
>>>>> Do not config MUSB to highspeed mode if
>>>>> CONFIG_USB_GADGET_DUALSPEED is not set, in which case Ether
>>>>> gadget only operates in fullspeed.
>>>>>
>>>>> Note: This patch is necessary for devices like some siemens
>>>>> boards that allow only FULL SPEED USB 1.1, e.g. DFU
>>>>> download.
>>>>>
>>>>> Signed-off-by: Bin Liu <b-liu at ti.com> Reviewed-by: Tom Rini
>>>>> <trini at konsulko.com> Tested-by: Samuel Egli
>>>>> <samuel.egli at siemens.com> CC: Marek Vasut <marex at denx.de> CC:
>>>>> Heiko Schocher <hs at denx.de> CC: Daniel Mack
>>>>> <zonque at gmail.com> CC: Roger Meier <r.meier at siemens.com>
>>>>
>>>> Nack this breaks highspeed mode on boards which use the musb in
>>>> host mode, and thus do not set CONFIG_USB_GADGET_DUALSPEED.

My bad, I had a short thought about this when I was initially working on
this patch, but did not really think about it throughly. Thanks for
bring it up.

>>>
>>> p.s.
>>>
>>> Given that you want to use this as a hack to work around the
>>> broken pcb design of your board I suggest adding a new option for
>>> this
>>
>> Well, lets not discuss the "broken" pcb design. It seems that
>> wiring protection is not that common. Unfortunately, such a
>> protection is too expensive for USB High speed :-(.

Agreed, we have seen many cases that have nothing to do with hardware
design, but MUSB has to work in full-speed mode.

>>
>>> titled: CONFIG_USB_MUSB_NO_HIGHSPEED and then do:
>>>
>>> +#ifndef CONFIG_USB_MUSB_NO_HIGHSPEED | MUSB_POWER_HSENAB
>>> +#endif
>>>
>> This would be good enough. The point is indeed to limit it to full
>> speed.
>>
>>> Using CONFIG_USB_GADGET_DUALSPEED for this seems wrong, since
>>> this has nothing to do with enabling dualspeed mode for the
>>> gadget code really.
>>
>> I agree that the name is confusing.
>
> Yes, I vote for Hans suggestion.

*Adding* a new macro CONFIG_USB_MUSB_NO_HIGHSPEED for musb driver causes
CONFIG_USB_GADGET_DUALSPEED redundant, because both control for full-speed.

I suggest to *rename* CONFIG_USB_GADGET_DUALSPEED to
CONFIG_USB_FULLSPEED_ONLY. So that we can use one macro for both gadget
and musb drivers. Considering supper-speed exists and future, I think
CONFIG_USB_NO_HIGHSPEED is confusing...

Regards,
-Bin.

>
> bye, Heiko