diff options
Diffstat (limited to 'drivers/usb/host/ehci-hcd.c')
| -rw-r--r-- | drivers/usb/host/ehci-hcd.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 28fb5ddaf786..9c2afb516fe5 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -118,9 +118,34 @@ MODULE_PARM_DESC(hird, "host initiated resume duration, +1 for each 75us"); /*-------------------------------------------------------------------------*/ #include "ehci.h" -#include "ehci-dbg.c" #include "pci-quirks.h" +/* + * The MosChip MCS9990 controller updates its microframe counter + * a little before the frame counter, and occasionally we will read + * the invalid intermediate value. Avoid problems by checking the + * microframe number (the low-order 3 bits); if they are 0 then + * re-read the register to get the correct value. + */ +static unsigned ehci_moschip_read_frame_index(struct ehci_hcd *ehci) +{ + unsigned uf; + + uf = ehci_readl(ehci, &ehci->regs->frame_index); + if (unlikely((uf & 7) == 0)) + uf = ehci_readl(ehci, &ehci->regs->frame_index); + return uf; +} + +static inline unsigned ehci_read_frame_index(struct ehci_hcd *ehci) +{ + if (ehci->frame_index_bug) + return ehci_moschip_read_frame_index(ehci); + return ehci_readl(ehci, &ehci->regs->frame_index); +} + +#include "ehci-dbg.c" + /*-------------------------------------------------------------------------*/ /* |