usb: dwc3: switch to peripheral mode when exiting

This allow the phy to enter idle and then suspend.
the K2 platforms require the PHY to be suspended before the USB domain
clock can be turned off.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 2498f0efb1a488aee4854e51072852fde5ad8a4f..1bd41f8bc771da6a324d6b5e4547ce721bf0da24 100644 (file)
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -581,6 +581,12 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
        return 0;
 }
 
+static void dwc3_gadget_run(struct dwc3 *dwc)
+{
+       dwc3_writel(dwc->regs, DWC3_DCTL, DWC3_DCTL_RUN_STOP);
+       mdelay(100);
+}
+
 static void dwc3_core_exit_mode(struct dwc3 *dwc)
 {
        switch (dwc->dr_mode) {
@@ -598,6 +604,13 @@ static void dwc3_core_exit_mode(struct dwc3 *dwc)
                /* do nothing */
                break;
        }
+
+       /*
+        * switch back to peripheral mode
+        * This enables the phy to enter idle and then, if enabled, suspend.
+        */
+       dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
+       dwc3_gadget_run(dwc);
 }
 
 #define DWC3_ALIGN_MASK                (16 - 1)