On 05/10/2011 01:20 PM, Sergei Shtylyov wrote:
> Hello.
>
> On 09-05-2011 21:46, Jan Andersson wrote:
>
>> This patch adds support for big endian GRUSBHC UHCI controllers.
>> The HCD bus glue will probe the register interface to determine
>> the endianness of the controller.
>
>> Tested on GR-LEON4-ITX board which has a controller with little endian
>> interface and on custom LEON3 board with a BE controller.
>
>> Signed-off-by: Jan Andersson<jan@xxxxxxxxxxx>
> [...]
>
>> diff --git a/drivers/usb/host/uhci-grlib.c b/drivers/usb/host/uhci-grlib.c
>> index b1addd6..81f741a 100644
>> --- a/drivers/usb/host/uhci-grlib.c
>> +++ b/drivers/usb/host/uhci-grlib.c
>> @@ -25,6 +25,23 @@ static int uhci_grlib_init(struct usb_hcd *hcd)
>> {
>> struct uhci_hcd *uhci = hcd_to_uhci(hcd);
>>
>> + /* Assign function pointers that will be used for register accesses.
>> + * Probe to see if we have a big or little endian controller. Bit 7
>> + * of PORTSC is always 1 and 15:13 are always zero, so we have:
>
> That's 3 bits, and your picture only has 2 bits zeroed. Also, what about
> bits 31:30 that are also zeroed on your picture?
You are correct, there should be a string of three zeros. 31:30 is 15:14
of the next PORTSC. It is possible that there is only one PORTSC with
this controller and that is why it does not say:
1------- 00------ _1_------- 00------
00------ 1------- 00------ _1_-------
Thank you,
Jan
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