[PATCH v2 4/4] Revert "usb: gadget: f_uvc: change endpoint allocation in uvc_function_bind()"

From: Frank Li
Date: Sun Dec 24 2023 - 10:40:07 EST


This reverts commit 3c5b006f3ee800b4bd9ed37b3a8f271b8560126e.

gadget_is_{super|dual}speed() API check UDC controller capitblity. It
should pass down highest speed endpoint descriptor to UDC controller. So
UDC controller driver can reserve enough resource at check_config(),
especially mult and maxburst. So UDC driver (such as cdns3) can know need
at least (mult + 1) * (maxburst + 1) * wMaxPacketSize internal memory for
this uvc functions.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
drivers/usb/gadget/function/f_uvc.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index faa398109431f..3d5c03e1361e4 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -719,13 +719,29 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
}
uvc->enable_interrupt_ep = opts->enable_interrupt_ep;

- ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
+ /*
+ * gadget_is_{super|dual}speed() API check UDC controller capitblity. It should pass down
+ * highest speed endpoint descriptor to UDC controller. So UDC controller driver can reserve
+ * enough resource at check_config(), especially mult and maxburst. So UDC driver (such as
+ * cdns3) can know need at least (mult + 1) * (maxburst + 1) * wMaxPacketSize internal
+ * memory for this uvc functions. This is the only straightforward method to resolve the UDC
+ * resource allocation issue in the current gadget framework.
+ */
+ if (gadget_is_superspeed(c->cdev->gadget))
+ ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
+ &uvc_ss_streaming_comp);
+ else if (gadget_is_dualspeed(cdev->gadget))
+ ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
+ else
+ ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
+
if (!ep) {
uvcg_info(f, "Unable to allocate streaming EP\n");
goto error;
}
uvc->video.ep = ep;

+ uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;

--
2.34.1