USB: gadget: Implement remote wakeup in ci13xxx_udc

This patch adds support for remote wakeup.  The following things
are handled:

- Process SET_FEATURE/CLEAR_FEATURE control requests sent by host
for enabling/disabling remote wakeup feature.
- Report remote wakeup enable status in response to GET_STATUS
control request.
- Implement wakeup method defined in usb_gadget_ops for initiating
remote wakeup.
- Notify gadget driver about suspend and resume.

Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 99 insertions, 29 deletions

diff --git a/drivers/usb/gadget/ci13xxx_udc.c b/drivers/usb/gadget/ci13xxx_udc.c
index da01f333a51c..17526759c9ce 100644
--- a/drivers/usb/gadget/ci13xxx_udc.c
+++ b/drivers/usb/gadget/ci13xxx_udc.c
@@ -1608,12 +1608,19 @@ static int _gadget_stop_activity(struct usb_gadget *gadget)
 {
         struct usb_ep *ep;
         struct ci13xxx    *udc = container_of(gadget, struct ci13xxx, gadget);
+        unsigned long flags;
 
         trace("%p", gadget);
 
         if (gadget == NULL)
                 return -EINVAL;
 
+        spin_lock_irqsave(udc->lock, flags);
+        udc->gadget.speed = USB_SPEED_UNKNOWN;
+        udc->remote_wakeup = 0;
+        udc->suspended = 0;
+        spin_unlock_irqrestore(udc->lock, flags);
+
         /* flush all endpoints */
         gadget_for_each_ep(ep, gadget) {
                 usb_ep_fifo_flush(ep);
@@ -1747,7 +1754,8 @@ __acquires(mEp->lock)
         }
 
         if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
-                /* TODO: D1 - Remote Wakeup; D0 - Self Powered */
+                /* Assume that device is bus powered for now. */
+                *((u16 *)req->buf) = _udc->remote_wakeup << 1;
                 retval = 0;
         } else if ((setup->bRequestType & USB_RECIP_MASK) \
                    == USB_RECIP_ENDPOINT) {
@@ -1913,22 +1921,32 @@ __acquires(udc->lock)
 
                 switch (req.bRequest) {
                 case USB_REQ_CLEAR_FEATURE:
-                        if (type != (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
-                            le16_to_cpu(req.wValue) != USB_ENDPOINT_HALT)
-                                goto delegate;
-                        if (req.wLength != 0)
-                                break;
-                        num  = le16_to_cpu(req.wIndex);
-                        num &= USB_ENDPOINT_NUMBER_MASK;
-                        if (!udc->ci13xxx_ep[num].wedge) {
-                                spin_unlock(udc->lock);
-                                err = usb_ep_clear_halt(
-                                        &udc->ci13xxx_ep[num].ep);
-                                spin_lock(udc->lock);
-                                if (err)
+                        if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
+                                        le16_to_cpu(req.wValue) ==
+                                        USB_ENDPOINT_HALT) {
+                                if (req.wLength != 0)
+                                        break;
+                                num  = le16_to_cpu(req.wIndex);
+                                num &= USB_ENDPOINT_NUMBER_MASK;
+                                if (!udc->ci13xxx_ep[num].wedge) {
+                                        spin_unlock(udc->lock);
+                                        err = usb_ep_clear_halt(
+                                                &udc->ci13xxx_ep[num].ep);
+                                        spin_lock(udc->lock);
+                                        if (err)
+                                                break;
+                                }
+                                err = isr_setup_status_phase(udc);
+                        } else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
+                                        le16_to_cpu(req.wValue) ==
+                                        USB_DEVICE_REMOTE_WAKEUP) {
+                                if (req.wLength != 0)
                                         break;
+                                udc->remote_wakeup = 0;
+                                err = isr_setup_status_phase(udc);
+                        } else {
+                                goto delegate;
                         }
-                        err = isr_setup_status_phase(udc);
                         break;
                 case USB_REQ_GET_STATUS:
                         if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
@@ -1952,20 +1970,29 @@ __acquires(udc->lock)
                         err = isr_setup_status_phase(udc);
                         break;
                 case USB_REQ_SET_FEATURE:
-                        if (type != (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
-                            le16_to_cpu(req.wValue) != USB_ENDPOINT_HALT)
-                                goto delegate;
-                        if (req.wLength != 0)
-                                break;
-                        num  = le16_to_cpu(req.wIndex);
-                        num &= USB_ENDPOINT_NUMBER_MASK;
+                        if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
+                                        le16_to_cpu(req.wValue) ==
+                                        USB_ENDPOINT_HALT) {
+                                if (req.wLength != 0)
+                                        break;
+                                num  = le16_to_cpu(req.wIndex);
+                                num &= USB_ENDPOINT_NUMBER_MASK;
 
-                        spin_unlock(udc->lock);
-                        err = usb_ep_set_halt(&udc->ci13xxx_ep[num].ep);
-                        spin_lock(udc->lock);
-                        if (err)
-                                break;
-                        err = isr_setup_status_phase(udc);
+                                spin_unlock(udc->lock);
+                                err = usb_ep_set_halt(&udc->ci13xxx_ep[num].ep);
+                                spin_lock(udc->lock);
+                                if (!err)
+                                        err = isr_setup_status_phase(udc);
+                        } else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
+                                        le16_to_cpu(req.wValue) ==
+                                        USB_DEVICE_REMOTE_WAKEUP) {
+                                if (req.wLength != 0)
+                                        break;
+                                udc->remote_wakeup = 1;
+                                err = isr_setup_status_phase(udc);
+                        } else {
+                                goto delegate;
+                        }
                         break;
                 default:
 delegate:
@@ -2401,6 +2428,31 @@ static int ci13xxx_vbus_session(struct usb_gadget *_gadget, int is_active)
         return 0;
 }
 
+static int ci13xxx_wakeup(struct usb_gadget *_gadget)
+{
+        struct ci13xxx *udc = container_of(_gadget, struct ci13xxx, gadget);
+        unsigned long flags;
+        int ret = 0;
+
+        trace();
+
+        spin_lock_irqsave(udc->lock, flags);
+        if (!udc->remote_wakeup) {
+                ret = -EOPNOTSUPP;
+                dbg_trace("remote wakeup feature is not enabled\n");
+                goto out;
+        }
+        if (!hw_cread(CAP_PORTSC, PORTSC_SUSP)) {
+                ret = -EINVAL;
+                dbg_trace("port is not suspended\n");
+                goto out;
+        }
+        hw_cwrite(CAP_PORTSC, PORTSC_FPR, PORTSC_FPR);
+out:
+        spin_unlock_irqrestore(udc->lock, flags);
+        return ret;
+}
+
 /**
  * Device operations part of the API to the USB controller hardware,
  * which don't involve endpoints (or i/o)
@@ -2408,6 +2460,7 @@ static int ci13xxx_vbus_session(struct usb_gadget *_gadget, int is_active)
  */
 static const struct usb_gadget_ops usb_gadget_ops = {
         .vbus_session   = ci13xxx_vbus_session,
+        .wakeup         = ci13xxx_wakeup,
 };
 
 /**
@@ -2650,6 +2703,12 @@ static irqreturn_t udc_irq(void)
                         isr_statistics.pci++;
                         udc->gadget.speed = hw_port_is_high_speed() ?
                                 USB_SPEED_HIGH : USB_SPEED_FULL;
+                        if (udc->suspended) {
+                                spin_unlock(udc->lock);
+                                udc->driver->resume(&udc->gadget);
+                                spin_lock(udc->lock);
+                                udc->suspended = 0;
+                        }
                 }
                 if (USBi_UEI & intr)
                         isr_statistics.uei++;
@@ -2657,8 +2716,15 @@ static irqreturn_t udc_irq(void)
                         isr_statistics.ui++;
                         isr_tr_complete_handler(udc);
                 }
-                if (USBi_SLI & intr)
+                if (USBi_SLI & intr) {
+                        if (udc->gadget.speed != USB_SPEED_UNKNOWN) {
+                                udc->suspended = 1;
+                                spin_unlock(udc->lock);
+                                udc->driver->suspend(&udc->gadget);
+                                spin_lock(udc->lock);
+                        }
                         isr_statistics.sli++;
+                }
                 retval = IRQ_HANDLED;
         } else {
                 isr_statistics.none++;
diff --git a/drivers/usb/gadget/ci13xxx_udc.h b/drivers/usb/gadget/ci13xxx_udc.h
index 3fad3adeacc8..6cfab20db6bd 100644
--- a/drivers/usb/gadget/ci13xxx_udc.h
+++ b/drivers/usb/gadget/ci13xxx_udc.h
@@ -128,6 +128,9 @@ struct ci13xxx {
         u32                        ep0_dir;    /* ep0 direction */
 #define ep0out ci13xxx_ep[0]
 #define ep0in  ci13xxx_ep[16]
+        u8                         remote_wakeup; /* Is remote wakeup feature
+                                                        enabled by the host? */
+        u8                         suspended;  /* suspended by the host */
 
         struct usb_gadget_driver  *driver;     /* 3rd party gadget driver */
         struct ci13xxx_udc_driver *udc_driver; /* device controller driver */
@@ -169,6 +172,7 @@ struct ci13xxx {
 #define DEVICEADDR_USBADR     (0x7FUL << 25)
 
 /* PORTSC */
+#define PORTSC_FPR            BIT(6)
 #define PORTSC_SUSP           BIT(7)
 #define PORTSC_HSP            BIT(9)
 #define PORTSC_PTC            (0x0FUL << 16)