usb: mtu3: fix interval value for intr and isoc

[ Upstream commit e3d4621c22f90c33321ae6a6baab60cdb8e5a77c ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/usb/mtu3/mtu3_gadget.c b/drivers/usb/mtu3/mtu3_gadget.c
index 0b21da4ee1836ebfd547effbb8b71e294d754d5c..9977600616d7ea1957dac214691d8b8844df1d2d 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;