diff options
Diffstat (limited to 'include/linux/usb/mctp-usb.h')
| -rw-r--r-- | include/linux/usb/mctp-usb.h | 88 |
1 files changed, 83 insertions, 5 deletions
diff --git a/include/linux/usb/mctp-usb.h b/include/linux/usb/mctp-usb.h index a2f6f1e04efb..4bb04a371105 100644 --- a/include/linux/usb/mctp-usb.h +++ b/include/linux/usb/mctp-usb.h @@ -2,7 +2,7 @@ /* * mctp-usb.h - MCTP USB transport binding: common definitions, * based on DMTF0283 specification: - * https://www.dmtf.org/sites/default/files/standards/documents/DSP0283_1.0.1.pdf + * https://www.dmtf.org/sites/default/files/standards/documents/DSP0283_1.1.0.pdf * * These are protocol-level definitions, that may be shared between host * and gadget drivers. @@ -13,18 +13,96 @@ #ifndef __LINUX_USB_MCTP_USB_H #define __LINUX_USB_MCTP_USB_H +#include <linux/netdevice.h> +#include <linux/skbuff.h> #include <linux/types.h> +/* + * MCTP-over-USB transport header. DSP0283 v1.0 has an 8-bit length field + * (preceded by 8 reserved bits), v1.1 has a 13-bit length field (preceded by + * 3 reserved bits). We use a be16 for our length to handle the larger v1.1 + * representation, and mask as appropriate. + */ struct mctp_usb_hdr { __be16 id; - u8 rsvd; - u8 len; + __be16 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_PKTLEN_MAX U8_MAX +#define MCTP_USB_1_0_MTU_MAX (MCTP_USB_1_0_PKTLEN_MAX - sizeof(struct mctp_usb_hdr)) +#define MCTP_USB_1_1_PKTLEN_MAX GENMASK(12, 0) +#define MCTP_USB_1_1_MTU_MAX (MCTP_USB_1_1_PKTLEN_MAX - sizeof(struct mctp_usb_hdr)) #define MCTP_USB_DMTF_ID 0x1ab4 +/* mctp-usblib */ + +/* + * RX handle: drivers will typically create one on init, which persists for + * the life of the driver. The same handle is used for progressive + * prepare -> complete operations (for each incoming USB transfer), which + * result in netif_rx()-ing the MCTP packets received + */ +struct mctp_usblib_rx { + struct sk_buff *skb; + u16 ep_pktlen; + bool span; +}; + +int mctp_usblib_rx_init(struct mctp_usblib_rx *rx, u16 ep_pktlen, bool span); +void mctp_usblib_rx_fini(struct mctp_usblib_rx *rx); + +int mctp_usblib_rx_prepare(struct net_device *netdev, + struct mctp_usblib_rx *rx, + void **bufp, size_t *lenp, gfp_t gfp); + +int mctp_usblib_rx_complete(struct net_device *netdev, + struct mctp_usblib_rx *rx, size_t len); + +void mctp_usblib_rx_cancel(struct mctp_usblib_rx *rx); + +/* + * TX handle: created by mctp_usblib_tx_push() during the tx path, and + * may persist across multiple packet transmits. + */ +struct mctp_usblib_tx_ctx; + +struct mctp_usblib_tx_ops { + /* Start a USB TX for @data. On returning success, the implementation + * must arrange for mctp_usblib_tx_send_complete() to be called at some + * later point (eg., on urb completion). + */ + int (*send)(struct mctp_usblib_tx_ctx *tx_ctx, void *data, size_t len); +}; + +struct mctp_usblib_tx { + struct mctp_usblib_tx_ops ops; + void *priv; + bool span; + /* protects access to cur_ctx */ + spinlock_t lock; + /* context to which we are adding packets, cleared on send */ + struct mctp_usblib_tx_ctx *cur_ctx; +}; + +void mctp_usblib_tx_init(struct mctp_usblib_tx *tx, + const struct mctp_usblib_tx_ops *ops, void *priv, + bool span); +void mctp_usblib_tx_fini(struct mctp_usblib_tx *tx); + +void *mctp_usblib_tx_ctx_priv(struct mctp_usblib_tx_ctx *tx_ctx); + +int mctp_usblib_tx_push(struct net_device *dev, + struct mctp_usblib_tx *tx, + struct sk_buff *skb, bool more); + +void mctp_usblib_tx_send_complete(struct mctp_usblib_tx_ctx *tx_ctx, + struct net_device *dev, bool ok); + +void mctp_usblib_tx_cancel(struct mctp_usblib_tx *tx, struct net_device *dev, + enum skb_drop_reason reason); + #endif /* __LINUX_USB_MCTP_USB_H */ |