diff options
Diffstat (limited to 'net/caif/cfdgml.c')
| -rw-r--r-- | net/caif/cfdgml.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/net/caif/cfdgml.c b/net/caif/cfdgml.c new file mode 100644 index 00000000..0382dec8 --- /dev/null +++ b/net/caif/cfdgml.c @@ -0,0 +1,112 @@ +/* + * Copyright (C) ST-Ericsson AB 2010 + * Author: Sjur Brendeland/sjur.brandeland@stericsson.com + * License terms: GNU General Public License (GPL) version 2 + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__ + +#include <linux/stddef.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <net/caif/caif_layer.h> +#include <net/caif/cfsrvl.h> +#include <net/caif/cfpkt.h> + + +#define container_obj(layr) ((struct cfsrvl *) layr) + +#define DGM_CMD_BIT 0x80 +#define DGM_FLOW_OFF 0x81 +#define DGM_FLOW_ON 0x80 +#define DGM_MTU 1500 + +static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt); +static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt); + +struct cflayer *cfdgml_create(u8 channel_id, struct dev_info *dev_info) +{ + struct cfsrvl *dgm = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC); + if (!dgm) { + pr_warn("Out of memory\n"); + return NULL; + } + caif_assert(offsetof(struct cfsrvl, layer) == 0); + memset(dgm, 0, sizeof(struct cfsrvl)); + cfsrvl_init(dgm, channel_id, dev_info, true); + dgm->layer.receive = cfdgml_receive; + dgm->layer.transmit = cfdgml_transmit; + snprintf(dgm->layer.name, CAIF_LAYER_NAME_SZ - 1, "dgm%d", channel_id); + dgm->layer.name[CAIF_LAYER_NAME_SZ - 1] = '\0'; + return &dgm->layer; +} + +static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt) +{ + u8 cmd = -1; + u8 dgmhdr[3]; + int ret; + caif_assert(layr->up != NULL); + caif_assert(layr->receive != NULL); + caif_assert(layr->ctrlcmd != NULL); + + if (cfpkt_extr_head(pkt, &cmd, 1) < 0) { + pr_err("Packet is erroneous!\n"); + cfpkt_destroy(pkt); + return -EPROTO; + } + + if ((cmd & DGM_CMD_BIT) == 0) { + if (cfpkt_extr_head(pkt, &dgmhdr, 3) < 0) { + pr_err("Packet is erroneous!\n"); + cfpkt_destroy(pkt); + return -EPROTO; + } + ret = layr->up->receive(layr->up, pkt); + return ret; + } + + switch (cmd) { + case DGM_FLOW_OFF: /* FLOW OFF */ + layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0); + cfpkt_destroy(pkt); + return 0; + case DGM_FLOW_ON: /* FLOW ON */ + layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0); + cfpkt_destroy(pkt); + return 0; + default: + cfpkt_destroy(pkt); + pr_info("Unknown datagram control %d (0x%x)\n", cmd, cmd); + return -EPROTO; + } +} + +static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt) +{ + u8 packet_type; + u32 zero = 0; + struct caif_payload_info *info; + struct cfsrvl *service = container_obj(layr); + int ret; + if (!cfsrvl_ready(service, &ret)) + return ret; + + /* STE Modem cannot handle more than 1500 bytes datagrams */ + if (cfpkt_getlen(pkt) > DGM_MTU) + return -EMSGSIZE; + + cfpkt_add_head(pkt, &zero, 3); + packet_type = 0x08; /* B9 set - UNCLASSIFIED */ + cfpkt_add_head(pkt, &packet_type, 1); + + /* Add info for MUX-layer to route the packet out. */ + info = cfpkt_info(pkt); + info->channel_id = service->layer.id; + /* To optimize alignment, we add up the size of CAIF header + * before payload. + */ + info->hdr_len = 4; + info->dev_info = &service->dev_info; + return layr->dn->transmit(layr->dn, pkt); +} |