diff options
| -rw-r--r-- | drivers/net/usb/ipheth.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 069979e2bb6e..03249208612e 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -61,7 +61,18 @@ #define IPHETH_USBINTF_PROTO 1 #define IPHETH_IP_ALIGN 2 /* padding at front of URB */ -#define IPHETH_NCM_HEADER_SIZE (12 + 96) /* NCMH + NCM0 */ +/* On iOS devices, NCM headers in RX have a fixed size regardless of DPE count: + * - NTH16 (NCMH): 12 bytes, as per CDC NCM 1.0 spec + * - NDP16 (NCM0): 96 bytes, of which + * - NDP16 fixed header: 8 bytes + * - maximum of 22 DPEs (21 datagrams + trailer), 4 bytes each + */ +#define IPHETH_NDP16_MAX_DPE 22 +#define IPHETH_NDP16_HEADER_SIZE (sizeof(struct usb_cdc_ncm_ndp16) + \ + IPHETH_NDP16_MAX_DPE * \ + sizeof(struct usb_cdc_ncm_dpe16)) +#define IPHETH_NCM_HEADER_SIZE (sizeof(struct usb_cdc_ncm_nth16) + \ + IPHETH_NDP16_HEADER_SIZE) #define IPHETH_TX_BUF_SIZE ETH_FRAME_LEN #define IPHETH_RX_BUF_SIZE_LEGACY (IPHETH_IP_ALIGN + ETH_FRAME_LEN) #define IPHETH_RX_BUF_SIZE_NCM 65536 |