Re: [PATCH v5] usb: usb3.0 ch9 definitions

[tlinder]

Hi Matthew

Page 10-57 you're referring to defines the SuperSpeed USB Device
Capability descriptor for Hub Class. The descriptor itself is defined in
ch9 section 9.6.2.2 and the wReserved is not defined there. Thus the total
length of the descriptor is 10 bytes and not 12.
IMO we should follow the definition in ch9. It seems that ch 10 has a typo
in it. You're right about the errata. I found no reference to this issue
either.
I'll contact USB-IF regarding this issue.
Thanks for bringing this up!

Best regards
Tanya Brokhman

> On Sat, Oct 09, 2010 at 04:46:12PM +0200, Tatyana Brokhman wrote:
>> +/*
>> + * SuperSpeed USB Capability descriptor: Defines the set of SuperSpeed
>> USB
>> + * specific device level capabilities
>> + */
>> +#define		USB_SS_CAP_TYPE		3
>> +struct usb_ss_cap_descriptor {		/* Link Power Management */
>> +	__u8  bLength;
>> +	__u8  bDescriptorType;
>> +	__u8  bDevCapabilityType;
>> +	__u8  bmAttributes;
>> +#define USB_LTM_SUPPORT			(1 << 1) /* supports LTM */
>> +	__le16 wSpeedSupported;
>> +#define USB_LOW_SPEED_OPERATION		(1)	 /* Low speed operation */
>> +#define USB_FULL_SPEED_OPERATION	(1 << 1) /* Full speed operation */
>> +#define USB_HIGH_SPEED_OPERATION	(1 << 2) /* High speed operation */
>> +#define USB_5GBPS_OPERATION		(1 << 3) /* Operation at 5Gbps */
>> +	__u8  bFunctionalitySupport;
>> +	__u8  bU1devExitLat;
>> +	__le16 bU2DevExitLat;
>> +} __attribute__((packed));
>> +
>> +#define USB_DT_USB_SS_CAP_SIZE	10
>
> Hang on, if we're looking at page 10-57 of "USB 3 0 (11132008)-final.pdf",
> it's 12 bytes long with the last two bytes being wReserved.  Is there
> an erratum that changes this?  I just looked through
> "USB3_Errata [June 2010].pdf" and don't see any errata that look germane.
>
>


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