On Wed, 17 Jun 2009, Alek Du wrote:
> It is not simple just let ehci_qh contain the soft part, since the ehci_shadow requires
> the hardware part to be the first part...
>
> /*
> * Entries in periodic shadow table are pointers to one of four kinds
> * of data structure. That's dictated by the hardware; a type tag is
> * encoded in the low bits of the hardware's periodic schedule. Use
> * Q_NEXT_TYPE to get the tag.
> *
> * For entries in the async schedule, the type tag always says "qh".
> */
> union ehci_shadow {
> struct ehci_qh *qh; /* Q_TYPE_QH */
> struct ehci_itd *itd; /* Q_TYPE_ITD */
> struct ehci_sitd *sitd; /* Q_TYPE_SITD */
> struct ehci_fstn *fstn; /* Q_TYPE_FSTN */
> __hc32 *hw_next; /* (all types) */
> void *ptr;
> };
>
>
> Unless if I split all the ehci_qh, ehci_itd, ehci_sitd, ehci_fstn part into two parts...
>
> union ehci_shadow {
> struct ehci_qh_hw *qh; /* Q_TYPE_QH */
> struct ehci_itd_hw *itd; /* Q_TYPE_ITD */
> struct ehci_sitd_hw *sitd; /* Q_TYPE_SITD */
> struct ehci_fstn_hw *fstn; /* Q_TYPE_FSTN */
> __hc32 *hw_next; /* (all types) */
> void *ptr;
> };
I don't see any problem. Just do this:
union ehci_shadow {
struct ehci_qh_hw *qh_hw; /* Q_TYPE_QH */
struct ehci_itd *itd; /* Q_TYPE_ITD */
struct ehci_sitd *sitd; /* Q_TYPE_SITD */
struct ehci_fstn *fstn; /* Q_TYPE_FSTN */
__hc32 *hw_next; /* (all types) */
void *ptr;
};
Alan Stern
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