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* [PATCH v2] USB: dummy-hcd: fix power budget for SuperSpeed mode
@ 2019-09-04  8:30 Jacky.Cao
  0 siblings, 0 replies; only message in thread
From: Jacky.Cao @ 2019-09-04  8:30 UTC (permalink / raw)
  To: balbi, gregkh, linux-usb, linux-kernel; +Cc: Kento.A.Kobayashi, Jacky.Cao

The power budget for SuperSpeed mode should be 900 mA
according to USB3.0 specification.

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@sony.com>
---
Changes in v2:
  - Fix whitespace damage

 drivers/usb/gadget/udc/dummy_hcd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c
index f04e91e..a373f49 100644
--- a/drivers/usb/gadget/udc/dummy_hcd.c
+++ b/drivers/usb/gadget/udc/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_0	900	/* in mA */
 
 static const char	driver_name[] = "dummy_hcd";
 static const char	driver_desc[] = "USB Host+Gadget Emulator";
@@ -2439,7 +2440,7 @@ static int dummy_start_ss(struct dummy_hcd *dum_hcd)
 	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_0;
 	dummy_hcd_to_hcd(dum_hcd)->state = HC_STATE_RUNNING;
 	dummy_hcd_to_hcd(dum_hcd)->uses_new_polling = 1;
 #ifdef CONFIG_USB_OTG
-- 
2.7.4

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2019-09-04  8:30 [PATCH v2] USB: dummy-hcd: fix power budget for SuperSpeed mode Jacky.Cao

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