1 files changed, 46 insertions, 0 deletions

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 18e877ffe7b7..cd70cc886171 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -922,6 +922,52 @@ static void musb_generic_disable(struct musb *musb)
 }
 
 /*
+ * Program the HDRC to start (enable interrupts, dma, etc.).
+ */
+void musb_start(struct musb *musb)
+{
+        void __iomem    *regs = musb->mregs;
+        u8              devctl = musb_readb(regs, MUSB_DEVCTL);
+
+        dev_dbg(musb->controller, "<== devctl %02x\n", devctl);
+
+        /*  Set INT enable registers, enable interrupts */
+        musb->intrtxe = musb->epmask;
+        musb_writew(regs, MUSB_INTRTXE, musb->intrtxe);
+        musb->intrrxe = musb->epmask & 0xfffe;
+        musb_writew(regs, MUSB_INTRRXE, musb->intrrxe);
+        musb_writeb(regs, MUSB_INTRUSBE, 0xf7);
+
+        musb_writeb(regs, MUSB_TESTMODE, 0);
+
+        /* put into basic highspeed mode and start session */
+        musb_writeb(regs, MUSB_POWER, MUSB_POWER_ISOUPDATE
+                        | MUSB_POWER_HSENAB
+                        /* ENSUSPEND wedges tusb */
+                        /* | MUSB_POWER_ENSUSPEND */
+                   );
+
+        musb->is_active = 0;
+        devctl = musb_readb(regs, MUSB_DEVCTL);
+        devctl &= ~MUSB_DEVCTL_SESSION;
+
+        /* session started after:
+         * (a) ID-grounded irq, host mode;
+         * (b) vbus present/connect IRQ, peripheral mode;
+         * (c) peripheral initiates, using SRP
+         */
+        if (musb->port_mode != MUSB_PORT_MODE_HOST &&
+                        (devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS) {
+                musb->is_active = 1;
+        } else {
+                devctl |= MUSB_DEVCTL_SESSION;
+        }
+
+        musb_platform_enable(musb);
+        musb_writeb(regs, MUSB_DEVCTL, devctl);
+}
+
+/*
  * Make the HDRC stop (disable interrupts, etc.);
  * reversible by musb_start
  * called on gadget driver unregister