diff options
Diffstat (limited to 'drivers/usb/host/ehci-omap.c')
-rw-r--r-- | drivers/usb/host/ehci-omap.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-omap.c b/drivers/usb/host/ehci-omap.c index 992d963..8905ba4 100644 --- a/drivers/usb/host/ehci-omap.c +++ b/drivers/usb/host/ehci-omap.c @@ -116,6 +116,8 @@ #define OMAP_UHH_DEBUG_CSR (0x44) /* EHCI Register Set */ +#define EHCI_INSNREG04 (0xA0) +#define EHCI_INSNREG04_DISABLE_UNSUSPEND (1 << 5) #define EHCI_INSNREG05_ULPI (0xA4) #define EHCI_INSNREG05_ULPI_CONTROL_SHIFT 31 #define EHCI_INSNREG05_ULPI_PORTSEL_SHIFT 24 @@ -382,6 +384,18 @@ static int omap_start_ehc(struct ehci_hcd_omap *omap, struct usb_hcd *hcd) dev_dbg(omap->dev, "UHH setup done, uhh_hostconfig=%x\n", reg); + /* + * An undocumented "feature" in the OMAP3 EHCI controller, + * causes suspended ports to be taken out of suspend when + * the USBCMD.Run/Stop bit is cleared (for example when + * we do ehci_bus_suspend). + * This breaks suspend-resume if the root-hub is allowed + * to suspend. Writing 1 to this undocumented register bit + * disables this feature and restores normal behavior. + */ + ehci_omap_writel(omap->ehci_base, EHCI_INSNREG04, + EHCI_INSNREG04_DISABLE_UNSUSPEND); + if ((omap->port_mode[0] == EHCI_HCD_OMAP_MODE_TLL) || (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_TLL) || (omap->port_mode[2] == EHCI_HCD_OMAP_MODE_TLL)) { |