usb: mtu3: fix interval value for intr and isoc

Use the Interval value from isoc/intr endpoint descriptor, no need
minus one. The original code doesn't cause transfer error for
normal cases, but it may have side effect with respond time of ERDY
or tPingTimeout.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20211218095749.6250-1-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/mtu3/mtu3_gadget.c b/drivers/usb/mtu3/mtu3_gadget.c
index a9a65b4..c51be01 100644 (file)
--- a/drivers/usb/mtu3/mtu3_gadget.c
+++ b/drivers/usb/mtu3/mtu3_gadget.c
@@ -77,7 +77,7 @@ static int mtu3_ep_enable(struct mtu3_ep *mep)
                if (usb_endpoint_xfer_int(desc) ||
                                usb_endpoint_xfer_isoc(desc)) {
                        interval = desc->bInterval;
-                       interval = clamp_val(interval, 1, 16) - 1;
+                       interval = clamp_val(interval, 1, 16);
                        if (usb_endpoint_xfer_isoc(desc) && comp_desc)
                                mult = comp_desc->bmAttributes;
                }
@@ -89,7 +89,7 @@ static int mtu3_ep_enable(struct mtu3_ep *mep)
                if (usb_endpoint_xfer_isoc(desc) ||
                                usb_endpoint_xfer_int(desc)) {
                        interval = desc->bInterval;
-                       interval = clamp_val(interval, 1, 16) - 1;
+                       interval = clamp_val(interval, 1, 16);
                        mult = usb_endpoint_maxp_mult(desc) - 1;
                }
                break;