[PATCH 13/16] usb: composite: force gadget to be USB2 for HS only function

[peng.fan at nxp.com <peng.fan@nxp.com>]

From: Li Jun <jun.li@nxp.com>

If one of functions is not super speed capable, we need force the udc
to be high speed, this is an equivalent implementation of
usb_gadget_udc_set_speed() in kernel but simple, which set the gadget
max_speed to be high speed, so afterwards when start gadget duc can
set the HW to be USB 2.0 mode.

Reviewed-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Tested-by: faqiang.zhu <faqiang.zhu@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 drivers/usb/gadget/composite.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index abb42db6bd..5e7f488cfb 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -532,6 +532,19 @@ int usb_add_config(struct usb_composite_dev *cdev,
 		}
 	}
 
+	/*
+	 * If one function of config is not super speed capable,
+	 * force the gadget to be high speed so controller driver
+	 * can init HW to be USB 2.0
+	 */
+	if (gadget_is_superspeed(cdev->gadget)) {
+		list_for_each_entry(f, &config->functions, list) {
+			if (!f->ss_descriptors)
+				cdev->gadget->max_speed =
+					USB_SPEED_HIGH;
+		}
+	}
+
 	usb_ep_autoconfig_reset(cdev->gadget);
 
 	os_desc_config = config;
-- 
2.28.0