[PATCH 3.16 021/136] USB: dummy-hcd: fix power budget for SuperSpeed mode

[Ben Hutchings]

3.16.80-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: "Jacky.Cao@xxxxxxxx" <Jacky.Cao@xxxxxxxx>

commit 2636d49b64671d3d90ecc4daf971b58df3956519 upstream.

The power budget for SuperSpeed mode should be 900 mA
according to USB specification, so set the power budget
to 900mA for dummy_start_ss which is only used for
SuperSpeed mode.

If the max power consumption of SuperSpeed device is
larger than 500 mA, insufficient available bus power
error happens in usb_choose_configuration function
when the device connects to dummy hcd.

Signed-off-by: Jacky Cao <Jacky.Cao@xxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/16EA1F625E922C43B00B9D82250220500871CDE5@xxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/usb/gadget/dummy_hcd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/usb/gadget/dummy_hcd.c
+++ b/drivers/usb/gadget/dummy_hcd.c
@@ -50,6 +50,7 @@
 #define DRIVER_VERSION	"02 May 2005"
 
 #define POWER_BUDGET	500	/* in mA; use 8 for low-power port testing */
+#define POWER_BUDGET_3	900	/* in mA */
 
 static const char	driver_name[] = "dummy_hcd";
 static const char	driver_desc[] = "USB Host+Gadget Emulator";
@@ -2359,7 +2360,7 @@ static int dummy_start_ss(struct dummy_h
 	dum_hcd->rh_state = DUMMY_RH_RUNNING;
 	dum_hcd->stream_en_ep = 0;
 	INIT_LIST_HEAD(&dum_hcd->urbp_list);
-	dummy_hcd_to_hcd(dum_hcd)->power_budget = POWER_BUDGET;
+	dummy_hcd_to_hcd(dum_hcd)->power_budget = POWER_BUDGET_3;
 	dummy_hcd_to_hcd(dum_hcd)->state = HC_STATE_RUNNING;
 	dummy_hcd_to_hcd(dum_hcd)->uses_new_polling = 1;
 #ifdef CONFIG_USB_OTG