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 <[email protected]>
---
Changes in v3:
- Rename POWER_BUDGET_3_0 to POWER_BUDGET_3
- Update commit message from USB3.0 specification to USB specification
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 8414fac..3d499d9 100644
--- a/drivers/usb/gadget/udc/dummy_hcd.c
+++ b/drivers/usb/gadget/udc/dummy_hcd.c
@@ -48,6 +48,7 @@
#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";
@@ -2432,7 +2433,7 @@ 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;
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
On Thu, 5 Sep 2019 [email protected] wrote:
> 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 <[email protected]>
> ---
> Changes in v3:
> - Rename POWER_BUDGET_3_0 to POWER_BUDGET_3
> - Update commit message from USB3.0 specification to USB specification
>
> 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 8414fac..3d499d9 100644
> --- a/drivers/usb/gadget/udc/dummy_hcd.c
> +++ b/drivers/usb/gadget/udc/dummy_hcd.c
> @@ -48,6 +48,7 @@
> #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";
> @@ -2432,7 +2433,7 @@ 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;
> dummy_hcd_to_hcd(dum_hcd)->state = HC_STATE_RUNNING;
> dummy_hcd_to_hcd(dum_hcd)->uses_new_polling = 1;
> #ifdef CONFIG_USB_OTG
Acked-by: Alan Stern <[email protected]>
On Thu, Sep 05, 2019 at 04:11:57AM +0000, [email protected] wrote:
> 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 <[email protected]>
Does this "fix" a specific commit in the tree, and if so, what is the
commit id of that? Also, should this go to the stable kernel(s)?
thanks,
greg k-h
Hi,
>
> Does this "fix" a specific commit in the tree, and if so, what is the commit id of
> that? Also, should this go to the stable kernel(s)?
>
> thanks,
>
> greg k-h
No, this fix is not for specific commit since the POWER_BUDGET(500mA) is used for
SuperSpeed mode when dummy hcd added SuperSpeed support in commit(1cd8fd2887).
And I think it should be imported to stable kernel(s) considering the "insufficient
available bus power error" mentioned in commit message really happens. We reproduced
this issue with linux-3.10, linux-4.9 which we use and confirmed it can be solved by
this modification.
Regards
Jacky