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#ifndef _OSMOCOM_LAPDM_H
#define _OSMOCOM_LAPDM_H
#include <stdint.h>
#include <osmocom/core/timer.h>
#include <osmocom/core/msgb.h>
#include <osmocom/gsm/prim.h>
/*! \defgroup lapdm LAPDm implementation according to GSM TS 04.06
* @{
*/
/*! \file lapdm.h */
/* primitive related sutff */
/*! \brief LAPDm related primitives */
enum osmo_ph_prim {
PRIM_PH_DATA, /*!< \brief PH-DATA */
PRIM_PH_RACH, /*!< \brief PH-RANDOM_ACCESS */
PRIM_PH_CONN, /*!< \brief PH-CONNECT */
PRIM_PH_EMPTY_FRAME, /*!< \brief PH-EMPTY_FRAME */
PRIM_PH_RTS, /*!< \brief PH-RTS */
};
/*! \brief for PH-RANDOM_ACCESS.req */
struct ph_rach_req_param {
uint8_t ra; /*!< \brief Random Access */
uint8_t ta; /*!< \brief Timing Advance */
uint8_t tx_power; /*!< \brief Transmit Power */
uint8_t is_combined_ccch;/*!< \brief Are we using a combined CCCH? */
uint16_t offset; /*!< \brief Timing Offset */
};
/*! \brief for PH-RANDOM_ACCESS.ind */
struct ph_rach_ind_param {
uint8_t ra; /*!< \brief Random Access */
uint8_t acc_delay; /*!< \brief Delay in bit periods */
uint32_t fn; /*!< \brief GSM Frame Number at time of RA */
};
/*! \brief for PH-[UNIT]DATA.{req,ind} */
struct ph_data_param {
uint8_t link_id; /*!< \brief Link Identifier (Like RSL) */
uint8_t chan_nr; /*!< \brief Channel Number (Like RSL) */
};
/*! \brief for PH-CONN.ind */
struct ph_conn_ind_param {
uint32_t fn; /*!< \brief GSM Frame Number */
};
/*! \brief primitive header for LAPDm PH-SAP primitives */
struct osmo_phsap_prim {
struct osmo_prim_hdr oph; /*!< \brief generic primitive header */
union {
struct ph_data_param data;
struct ph_rach_req_param rach_req;
struct ph_rach_ind_param rach_ind;
struct ph_conn_ind_param conn_ind;
} u; /*!< \brief request-specific data */
};
/*! \brief LAPDm mode/role */
enum lapdm_mode {
LAPDM_MODE_MS, /*!< \brief behave like a MS (mobile phone) */
LAPDM_MODE_BTS, /*!< \brief behave like a BTS (network) */
};
/*! \brief LAPDm state */
enum lapdm_state {
LAPDm_STATE_NULL = 0,
LAPDm_STATE_IDLE,
LAPDm_STATE_SABM_SENT,
LAPDm_STATE_MF_EST,
LAPDm_STATE_TIMER_RECOV,
LAPDm_STATE_DISC_SENT,
};
struct lapdm_entity;
/*! \brief LAPDm message context */
struct lapdm_msg_ctx {
struct lapdm_datalink *dl;
int lapdm_fmt;
uint8_t n201;
uint8_t chan_nr;
uint8_t link_id;
uint8_t addr;
uint8_t ctrl;
uint8_t ta_ind;
uint8_t tx_power_ind;
};
/*! \brief LAPDm datalink like TS 04.06 / Section 3.5.2 */
struct lapdm_datalink {
uint8_t V_send; /*!< \brief seq nr of next I frame to be transmitted */
uint8_t V_ack; /*!< \brief last frame ACKed by peer */
uint8_t N_send; /*!< \brief ? set to V_send at Tx time*/
uint8_t V_recv; /*!< \brief seq nr of next I frame expected to be received */
uint8_t N_recv; /*!< \brief expected send seq nr of the next received I frame */
uint32_t state; /*!< \brief LAPDm state (\ref lapdm_state) */
int seq_err_cond; /*!< \brief condition of sequence error */
uint8_t own_busy; /*!< \brief receiver busy on our side */
uint8_t peer_busy; /*!< \brief receiver busy on remote side */
struct osmo_timer_list t200; /*!< \brief T200 timer */
uint8_t retrans_ctr; /*!< \brief re-transmission counter */
struct llist_head send_queue; /*!< \brief frames from L3 */
struct msgb *send_buffer; /*!< \brief current frame transmitting */
int send_out; /*!< \brief how much was sent from send_buffer */
uint8_t tx_hist[8][200]; /*!< \brief tx history buffer */
int tx_length[8]; /*!< \brief length in history buffer */
struct llist_head tx_queue; /*!< \brief frames to L1 */
struct lapdm_msg_ctx mctx; /*!< \brief context of established connection */
struct msgb *rcv_buffer; /*!< \brief buffer to assemble the received message */
struct lapdm_entity *entity; /*!< \brief LAPDm entity we are part of */
};
/*! \brief LAPDm datalink SAPIs */
enum lapdm_dl_sapi {
DL_SAPI0 = 0, /*!< \brief SAPI 0 */
DL_SAPI3 = 1, /*!< \brief SAPI 1 */
_NR_DL_SAPI
};
typedef int (*lapdm_cb_t)(struct msgb *msg, struct lapdm_entity *le, void *ctx);
struct lapdm_cr_ent {
uint8_t cmd;
uint8_t resp;
};
#define LAPDM_ENT_F_EMPTY_FRAME 0x0001
#define LAPDM_ENT_F_POLLING_ONLY 0x0002
/*! \brief a LAPDm Entity */
struct lapdm_entity {
/*! \brief the SAPIs of the LAPDm entity */
struct lapdm_datalink datalink[_NR_DL_SAPI];
int last_tx_dequeue; /*!< \brief last entity that was dequeued */
int tx_pending; /*!< \brief currently a pending frame not confirmed by L1 */
enum lapdm_mode mode; /*!< \brief are we in BTS mode or MS mode */
unsigned int flags;
struct {
/*! \brief filled-in once we set the lapdm_mode above */
struct lapdm_cr_ent loc2rem;
struct lapdm_cr_ent rem2loc;
} cr;
void *l1_ctx; /*!< \brief context for layer1 instance */
void *l3_ctx; /*!< \brief context for layer3 instance */
osmo_prim_cb l1_prim_cb;/*!< \brief callback for sending prims to L1 */
lapdm_cb_t l3_cb; /*!< \brief callback for sending stuff to L3 */
/*! \brief pointer to \ref lapdm_channel of which we're part */
struct lapdm_channel *lapdm_ch;
};
/*! \brief the two lapdm_entities that form a GSM logical channel (ACCH + DCCH) */
struct lapdm_channel {
struct llist_head list; /*!< \brief internal linked list */
char *name; /*!< \brief human-readable name */
struct lapdm_entity lapdm_acch; /*!< \brief Associated Control Channel */
struct lapdm_entity lapdm_dcch; /*!< \brief Dedicated Control Channel */
};
const char *get_rsl_name(int value);
extern const char *lapdm_state_names[];
/* initialize a LAPDm entity */
void lapdm_entity_init(struct lapdm_entity *le, enum lapdm_mode mode);
void lapdm_channel_init(struct lapdm_channel *lc, enum lapdm_mode mode);
/* deinitialize a LAPDm entity */
void lapdm_entity_exit(struct lapdm_entity *le);
void lapdm_channel_exit(struct lapdm_channel *lc);
/* input into layer2 (from layer 1) */
int lapdm_phsap_up(struct osmo_prim_hdr *oph, struct lapdm_entity *le);
/* input into layer2 (from layer 3) */
int lapdm_rslms_recvmsg(struct msgb *msg, struct lapdm_channel *lc);
void lapdm_channel_set_l3(struct lapdm_channel *lc, lapdm_cb_t cb, void *ctx);
void lapdm_channel_set_l1(struct lapdm_channel *lc, osmo_prim_cb cb, void *ctx);
int lapdm_entity_set_mode(struct lapdm_entity *le, enum lapdm_mode mode);
int lapdm_channel_set_mode(struct lapdm_channel *lc, enum lapdm_mode mode);
void lapdm_entity_reset(struct lapdm_entity *le);
void lapdm_channel_reset(struct lapdm_channel *lc);
void lapdm_entity_set_flags(struct lapdm_entity *le, unsigned int flags);
void lapdm_channel_set_flags(struct lapdm_channel *lc, unsigned int flags);
int lapdm_phsap_dequeue_prim(struct lapdm_entity *le, struct osmo_phsap_prim *pp);
/*! }@ */
#endif /* _OSMOCOM_LAPDM_H */
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