[PATCH net-next v3 01/12] net: mctp: usb: Include version indicator in max packet size defines
From: Jeremy Kerr <jk@codeconstruct.com.au>
Date: 2026-07-08 09:58:56
Also in:
linux-usb
Subsystem:
management component transport protocol (mctp), networking drivers, the rest, usb subsystem · Maintainers:
Jeremy Kerr, Matt Johnston, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Greg Kroah-Hartman
DSP0283 v1.1.0 will introduce larger maximum packet sizes. In preparation, indicate that the current maxima are specific to v1.0.x. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> --- drivers/net/mctp/mctp-usb.c | 8 ++++---- include/linux/usb/mctp-usb.h | 5 +++-- 2 files changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/net/mctp/mctp-usb.c b/drivers/net/mctp/mctp-usb.c
index fade65f2f269..545eff06322c 100644
--- a/drivers/net/mctp/mctp-usb.c
+++ b/drivers/net/mctp/mctp-usb.c@@ -76,7 +76,7 @@ static netdev_tx_t mctp_usb_start_xmit(struct sk_buff *skb, plen = skb->len; - if (plen + sizeof(*hdr) > MCTP_USB_XFER_SIZE) + if (plen + sizeof(*hdr) > MCTP_USB_1_0_XFER_SIZE) goto err_drop; rc = skb_cow_head(skb, sizeof(*hdr));
@@ -128,7 +128,7 @@ static int mctp_usb_rx_queue(struct mctp_usb *mctp_usb, gfp_t gfp) struct sk_buff *skb; int rc; - skb = __netdev_alloc_skb(mctp_usb->netdev, MCTP_USB_XFER_SIZE, gfp); + skb = __netdev_alloc_skb(mctp_usb->netdev, MCTP_USB_1_0_XFER_SIZE, gfp); if (!skb) { rc = -ENOMEM; goto err_retry;
@@ -136,7 +136,7 @@ static int mctp_usb_rx_queue(struct mctp_usb *mctp_usb, gfp_t gfp) usb_fill_bulk_urb(mctp_usb->rx_urb, mctp_usb->usbdev, usb_rcvbulkpipe(mctp_usb->usbdev, mctp_usb->ep_in), - skb->data, MCTP_USB_XFER_SIZE, + skb->data, MCTP_USB_1_0_XFER_SIZE, mctp_usb_in_complete, skb); rc = usb_submit_urb(mctp_usb->rx_urb, gfp);
@@ -301,7 +301,7 @@ static void mctp_usb_netdev_setup(struct net_device *dev) dev->mtu = MCTP_USB_MTU_MIN; dev->min_mtu = MCTP_USB_MTU_MIN; - dev->max_mtu = MCTP_USB_MTU_MAX; + dev->max_mtu = MCTP_USB_1_0_MTU_MAX; dev->hard_header_len = sizeof(struct mctp_usb_hdr); dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
diff --git a/include/linux/usb/mctp-usb.h b/include/linux/usb/mctp-usb.h
index a2f6f1e04efb..47e2e3931d63 100644
--- a/include/linux/usb/mctp-usb.h
+++ b/include/linux/usb/mctp-usb.h@@ -21,10 +21,11 @@ struct mctp_usb_hdr { u8 len; } __packed; -#define MCTP_USB_XFER_SIZE 512 +/* max transfer size for DSP0283 v1.0 */ +#define MCTP_USB_1_0_XFER_SIZE 512 #define MCTP_USB_BTU 68 #define MCTP_USB_MTU_MIN MCTP_USB_BTU -#define MCTP_USB_MTU_MAX (U8_MAX - sizeof(struct mctp_usb_hdr)) +#define MCTP_USB_1_0_MTU_MAX (U8_MAX - sizeof(struct mctp_usb_hdr)) #define MCTP_USB_DMTF_ID 0x1ab4 #endif /* __LINUX_USB_MCTP_USB_H */
--
2.47.3