mt76: usb: introduce disable_usb_sg parameter

Add disable_usb_sg module parameter to disable scatter-gather on demand

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c
index 0970a53d6ed522abc592d73a57418990352c6c45..c9f095c1f161b473b7ace19343888f23c6cf6db2 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/usb.c
@@ -22,6 +22,10 @@
 #define MT_VEND_REQ_MAX_RETRY  10
 #define MT_VEND_REQ_TOUT_MS    300
 
+static bool disable_usb_sg;
+module_param_named(disable_usb_sg, disable_usb_sg, bool, 0644);
+MODULE_PARM_DESC(disable_usb_sg, "Disable usb scatter-gather support");
+
 /* should be called with usb_ctrl_mtx locked */
 static int __mt76u_vendor_request(struct mt76_dev *dev, u8 req,
                                  u8 req_type, u16 val, u16 offset,
@@ -246,7 +250,7 @@ static bool mt76u_check_sg(struct mt76_dev *dev)
        struct usb_interface *intf = to_usb_interface(dev->dev);
        struct usb_device *udev = interface_to_usbdev(intf);
 
-       return (udev->bus->sg_tablesize > 0 &&
+       return (!disable_usb_sg && udev->bus->sg_tablesize > 0 &&
                (udev->bus->no_sg_constraint ||
                 udev->speed == USB_SPEED_WIRELESS));
 }