[PATCH v4 2/7] usb: dwc3: Switch to device mode on gadget start

[Sjoerd Simons]

When dr_mode is "otg" the dwc3 is initially configured in _OTG mode;
However in this mode the gadget functionality doesn't work without
further configuration. To resolve that on gadget start switch to _DEVICE
mode globally and go back to _OTG on stop again.

For this the dwc3_set_mode is renamed to dwc3_core_set_mode to avoid a
conflict with the same function exposed by xhci-dwc3

Signed-off-by: Sjoerd Simons <sjo...@collabora.com>

---

Changes in v4:
- New patch

 drivers/usb/dwc3/core.c   | 10 +++++-----
 drivers/usb/dwc3/core.h   |  1 +
 drivers/usb/dwc3/gadget.c |  6 ++++++
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 4b4fcd8a22e..d22d4c4bb6a 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -42,7 +42,7 @@
 static LIST_HEAD(dwc3_list);
 /* -------------------------------------------------------------------------- 
*/
 
-static void dwc3_set_mode(struct dwc3 *dwc, u32 mode)
+void dwc3_core_set_mode(struct dwc3 *dwc, u32 mode)
 {
        u32 reg;
 
@@ -736,7 +736,7 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
 
        switch (dwc->dr_mode) {
        case USB_DR_MODE_PERIPHERAL:
-               dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
+               dwc3_core_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
                ret = dwc3_gadget_init(dwc);
                if (ret) {
                        dev_err(dwc->dev, "failed to initialize gadget\n");
@@ -744,7 +744,7 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
                }
                break;
        case USB_DR_MODE_HOST:
-               dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_HOST);
+               dwc3_core_set_mode(dwc, DWC3_GCTL_PRTCAP_HOST);
                ret = dwc3_host_init(dwc);
                if (ret) {
                        dev_err(dwc->dev, "failed to initialize host\n");
@@ -752,7 +752,7 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
                }
                break;
        case USB_DR_MODE_OTG:
-               dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
+               dwc3_core_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
                ret = dwc3_host_init(dwc);
                if (ret) {
                        dev_err(dwc->dev, "failed to initialize host\n");
@@ -810,7 +810,7 @@ static void dwc3_core_exit_mode(struct dwc3 *dwc)
         * 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_core_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
        dwc3_gadget_run(dwc);
 }
 
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 4162a682298..1e7eda89a34 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1057,6 +1057,7 @@ int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc);
 void dwc3_of_parse(struct dwc3 *dwc);
 int dwc3_init(struct dwc3 *dwc);
 void dwc3_remove(struct dwc3 *dwc);
+void dwc3_core_set_mode(struct dwc3 *dwc, u32 mode);
 
 static inline int dwc3_host_init(struct dwc3 *dwc)
 { return 0; }
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 406d36ceafe..69d9fe40e2f 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1468,6 +1468,9 @@ static int dwc3_gadget_start(struct usb_gadget *g,
 
        dwc->gadget_driver      = driver;
 
+       if (dwc->dr_mode == DWC3_GCTL_PRTCAP_OTG)
+               dwc3_core_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
+
        reg = dwc3_readl(dwc->regs, DWC3_DCFG);
        reg &= ~(DWC3_DCFG_SPEED_MASK);
 
@@ -1559,6 +1562,9 @@ static int dwc3_gadget_stop(struct usb_gadget *g)
        __dwc3_gadget_ep_disable(dwc->eps[0]);
        __dwc3_gadget_ep_disable(dwc->eps[1]);
 
+       if (dwc->dr_mode == DWC3_GCTL_PRTCAP_OTG)
+               dwc3_core_set_mode(dwc, DWC3_GCTL_PRTCAP_OTG);
+
        dwc->gadget_driver      = NULL;
 
        spin_unlock_irqrestore(&dwc->lock, flags);
-- 
2.43.0