[PATCH] add usb transceiver set_suspend() method

When a USB device is put into suspend mode, the current drawn from VBUS
has to be less than 500 uA. Some transceivers need to be put into a
special power-saving mode to accomplish this, and won't have a separate
OTG driver handling that.

This adds a suspend method to the "otg_transceiver" struct -- misnamed,
it's not only for OTG -- and calls it from the OMAP UDC driver.

Signed-off-by: Juha Yrj?l? <juha.yrjola@nokia.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 17 insertions, 0 deletions

diff --git a/drivers/usb/gadget/omap_udc.c b/drivers/usb/gadget/omap_udc.c
index de8a89ae4bc3..b42799bc747a 100644
--- a/drivers/usb/gadget/omap_udc.c
+++ b/drivers/usb/gadget/omap_udc.c
@@ -1788,8 +1788,12 @@ static void devstate_irq(struct omap_udc *udc, u16 irq_src)
                                         udc->driver->suspend(&udc->gadget);
                                         spin_lock(&udc->lock);
                                 }
+                                if (udc->transceiver)
+                                        otg_set_suspend(udc->transceiver, 1);
                         } else {
                                 VDBG("resume\n");
+                                if (udc->transceiver)
+                                        otg_set_suspend(udc->transceiver, 0);
                                 if (udc->gadget.speed == USB_SPEED_FULL
                                                 && udc->driver->resume) {
                                         spin_unlock(&udc->lock);
diff --git a/include/linux/usb_otg.h b/include/linux/usb_otg.h
index c6683146e9b0..f827f6e203c2 100644
--- a/include/linux/usb_otg.h
+++ b/include/linux/usb_otg.h
@@ -63,6 +63,10 @@ struct otg_transceiver {
         int     (*set_power)(struct otg_transceiver *otg,
                                 unsigned mA);
 
+        /* for non-OTG B devices: set transceiver into suspend mode */
+        int     (*set_suspend)(struct otg_transceiver *otg,
+                                int suspend);
+
         /* for B devices only:  start session with A-Host */
         int     (*start_srp)(struct otg_transceiver *otg);
 
@@ -108,6 +112,15 @@ otg_set_power(struct otg_transceiver *otg, unsigned mA)
 }
 
 static inline int
+otg_set_suspend(struct otg_transceiver *otg, int suspend)
+{
+        if (otg->set_suspend != NULL)
+                return otg->set_suspend(otg, suspend);
+        else
+                return 0;
+}
+
+static inline int
 otg_start_srp(struct otg_transceiver *otg)
 {
         return otg->start_srp(otg);