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 253c8b71d3c4974cea4b724943ae1c1a3d1ba78f..061da9b82b96752ec478805600a4b30b8a46a797 100644 (file)
--- a/drivers/usb/mtu3/mtu3_gadget.c
+++ b/drivers/usb/mtu3/mtu3_gadget.c
@@ -85,7 +85,7 @@ 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;
                }
@@ -97,7 +97,7 @@ 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;