[PATCH v2 1/4] usb: mtu3: fix interval value for intr and isoc

Chunfeng Yun chunfeng.yun at mediatek.com
Sat Dec 18 01:57:46 PST 2021


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 at mediatek.com>
---
v2: modify commit message to explain more about the issue to be fixed
---
 drivers/usb/mtu3/mtu3_gadget.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/mtu3/mtu3_gadget.c b/drivers/usb/mtu3/mtu3_gadget.c
index a9a65b4bbfed..c51be015345b 100644
--- 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;
-- 
2.18.0




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