[PATCH RFC] usb: gadget: Set self-powered based on MaxPower and bmAttributes

[PATCH RFC] usb: gadget: Set self-powered based on MaxPower and bmAttributes

[Prashanth K]

Currently the USB gadget will be set as bus-powered based solely
on whether its bMaxPower is greater than 100mA, but this may miss
devices that may legitimately draw less than 100mA but still want
to report as bus-powered. Similarly during suspend & resume, USB
gadget is incorrectly marked as bus/self powered without checking
the bmAttributes field. Fix these by configuring the USB gadget
as self or bus powered based on bmAttributes, and explicitly set
it as bus-powered if it draws more than 100mA.

Cc: stable@vger.kernel.org
Fixes: 5e5caf4fa8d3 ("usb: gadget: composite: Inform controller driver of self-powered")
Signed-off-by: Prashanth K <prashanth.k@oss.qualcomm.com>
---
 drivers/usb/gadget/composite.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index bdda8c74602d..1fb28bbf6c45 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1050,10 +1050,11 @@ static int set_config(struct usb_composite_dev *cdev,
 	else
 		usb_gadget_set_remote_wakeup(gadget, 0);
 done:
-	if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
-		usb_gadget_set_selfpowered(gadget);
-	else
+	if (power > USB_SELF_POWER_VBUS_MAX_DRAW ||
+	    !(c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 		usb_gadget_clear_selfpowered(gadget);
+	else
+		usb_gadget_set_selfpowered(gadget);
 
 	usb_gadget_vbus_draw(gadget, power);
 	if (result >= 0 && cdev->delayed_status)
@@ -2615,7 +2616,9 @@ void composite_suspend(struct usb_gadget *gadget)
 
 	cdev->suspended = 1;
 
-	usb_gadget_set_selfpowered(gadget);
+	if (cdev->config->bmAttributes & USB_CONFIG_ATT_SELFPOWER)
+		usb_gadget_set_selfpowered(gadget);
+
 	usb_gadget_vbus_draw(gadget, 2);
 }
 
@@ -2649,8 +2652,11 @@ void composite_resume(struct usb_gadget *gadget)
 		else
 			maxpower = min(maxpower, 900U);
 
-		if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
+		if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW ||
+		    !(cdev->config->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
 			usb_gadget_clear_selfpowered(gadget);
+		else
+			usb_gadget_set_selfpowered(gadget);
 
 		usb_gadget_vbus_draw(gadget, maxpower);
 	} else {
-- 
2.25.1

Re: [PATCH RFC] usb: gadget: Set self-powered based on MaxPower and bmAttributes

[Greg Kroah-Hartman]

On Tue, Feb 04, 2025 at 04:29:08PM +0530, Prashanth K wrote:
> Currently the USB gadget will be set as bus-powered based solely
> on whether its bMaxPower is greater than 100mA, but this may miss
> devices that may legitimately draw less than 100mA but still want
> to report as bus-powered. Similarly during suspend & resume, USB
> gadget is incorrectly marked as bus/self powered without checking
> the bmAttributes field. Fix these by configuring the USB gadget
> as self or bus powered based on bmAttributes, and explicitly set
> it as bus-powered if it draws more than 100mA.
> 
> Cc: stable@vger.kernel.org
> Fixes: 5e5caf4fa8d3 ("usb: gadget: composite: Inform controller driver of self-powered")
> Signed-off-by: Prashanth K <prashanth.k@oss.qualcomm.com>
> ---
>  drivers/usb/gadget/composite.c | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)

What type of "comments" are you wanting here?

For obvious reasons, I can't apply patches tagged "RFC" but I don't see
what you are wanting us to do here.

confused,

greg k-h

Re: [PATCH RFC] usb: gadget: Set self-powered based on MaxPower and bmAttributes

[Prashanth K]

On 14-02-25 01:32 pm, Greg Kroah-Hartman wrote:
> On Tue, Feb 04, 2025 at 04:29:08PM +0530, Prashanth K wrote:
>> Currently the USB gadget will be set as bus-powered based solely
>> on whether its bMaxPower is greater than 100mA, but this may miss
>> devices that may legitimately draw less than 100mA but still want
>> to report as bus-powered. Similarly during suspend & resume, USB
>> gadget is incorrectly marked as bus/self powered without checking
>> the bmAttributes field. Fix these by configuring the USB gadget
>> as self or bus powered based on bmAttributes, and explicitly set
>> it as bus-powered if it draws more than 100mA.
>>
>> Cc: stable@vger.kernel.org
>> Fixes: 5e5caf4fa8d3 ("usb: gadget: composite: Inform controller driver of self-powered")
>> Signed-off-by: Prashanth K <prashanth.k@oss.qualcomm.com>
>> ---
>>  drivers/usb/gadget/composite.c | 16 +++++++++++-----
>>  1 file changed, 11 insertions(+), 5 deletions(-)
> 
> What type of "comments" are you wanting here?
> 
> For obvious reasons, I can't apply patches tagged "RFC" but I don't see
> what you are wanting us to do here.
> 
> confused,
> 
> greg k-h
Sent an RFC since I got some comments last time while changing few
things on this path, was expecting the same thing this time, Will send a v2.

Thanks,
Prashanth K