blob: 27dab26ad3b84ff213497bcd9029b7af75688560 [file] [log] [blame]
Sjur Braendelandb482cd22010-03-30 13:56:23 +00001/*
2 * Copyright (C) ST-Ericsson AB 2010
3 * Author: Sjur Brendeland/sjur.brandeland@stericsson.com
4 * License terms: GNU General Public License (GPL) version 2
5 */
6
Joe Perchesb31fa5b2010-09-05 21:31:11 +00007#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
8
Sjur Braendelandb482cd22010-03-30 13:56:23 +00009#include <linux/stddef.h>
10#include <linux/spinlock.h>
11#include <linux/slab.h>
12#include <net/caif/caif_layer.h>
13#include <net/caif/cfsrvl.h>
14#include <net/caif/cfpkt.h>
15
16#define container_obj(layr) ((struct cfsrvl *) layr)
17
18#define DGM_CMD_BIT 0x80
19#define DGM_FLOW_OFF 0x81
20#define DGM_FLOW_ON 0x80
Sjur Braendeland2aa40ae2010-06-17 06:55:40 +000021#define DGM_MTU 1500
Sjur Braendelandb482cd22010-03-30 13:56:23 +000022
23static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt);
24static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt);
25
26struct cflayer *cfdgml_create(u8 channel_id, struct dev_info *dev_info)
27{
28 struct cfsrvl *dgm = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
29 if (!dgm) {
Joe Perchesb31fa5b2010-09-05 21:31:11 +000030 pr_warn("Out of memory\n");
Sjur Braendelandb482cd22010-03-30 13:56:23 +000031 return NULL;
32 }
33 caif_assert(offsetof(struct cfsrvl, layer) == 0);
34 memset(dgm, 0, sizeof(struct cfsrvl));
Sjur Braendelandb1c74242010-06-17 06:55:38 +000035 cfsrvl_init(dgm, channel_id, dev_info, true);
Sjur Braendelandb482cd22010-03-30 13:56:23 +000036 dgm->layer.receive = cfdgml_receive;
37 dgm->layer.transmit = cfdgml_transmit;
38 snprintf(dgm->layer.name, CAIF_LAYER_NAME_SZ - 1, "dgm%d", channel_id);
39 dgm->layer.name[CAIF_LAYER_NAME_SZ - 1] = '\0';
40 return &dgm->layer;
41}
42
43static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt)
44{
45 u8 cmd = -1;
46 u8 dgmhdr[3];
47 int ret;
48 caif_assert(layr->up != NULL);
49 caif_assert(layr->receive != NULL);
50 caif_assert(layr->ctrlcmd != NULL);
51
52 if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
Joe Perchesb31fa5b2010-09-05 21:31:11 +000053 pr_err("Packet is erroneous!\n");
Sjur Braendelandb482cd22010-03-30 13:56:23 +000054 cfpkt_destroy(pkt);
55 return -EPROTO;
56 }
57
58 if ((cmd & DGM_CMD_BIT) == 0) {
59 if (cfpkt_extr_head(pkt, &dgmhdr, 3) < 0) {
Joe Perchesb31fa5b2010-09-05 21:31:11 +000060 pr_err("Packet is erroneous!\n");
Sjur Braendelandb482cd22010-03-30 13:56:23 +000061 cfpkt_destroy(pkt);
62 return -EPROTO;
63 }
64 ret = layr->up->receive(layr->up, pkt);
65 return ret;
66 }
67
68 switch (cmd) {
69 case DGM_FLOW_OFF: /* FLOW OFF */
70 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
71 cfpkt_destroy(pkt);
72 return 0;
73 case DGM_FLOW_ON: /* FLOW ON */
74 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
75 cfpkt_destroy(pkt);
76 return 0;
77 default:
78 cfpkt_destroy(pkt);
Joe Perchesb31fa5b2010-09-05 21:31:11 +000079 pr_info("Unknown datagram control %d (0x%x)\n", cmd, cmd);
Sjur Braendelandb482cd22010-03-30 13:56:23 +000080 return -EPROTO;
81 }
82}
83
84static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt)
85{
86 u32 zero = 0;
87 struct caif_payload_info *info;
88 struct cfsrvl *service = container_obj(layr);
89 int ret;
90 if (!cfsrvl_ready(service, &ret))
91 return ret;
92
Sjur Braendeland2aa40ae2010-06-17 06:55:40 +000093 /* STE Modem cannot handle more than 1500 bytes datagrams */
94 if (cfpkt_getlen(pkt) > DGM_MTU)
95 return -EMSGSIZE;
96
Sjur Braendelandb482cd22010-03-30 13:56:23 +000097 cfpkt_add_head(pkt, &zero, 4);
98
99 /* Add info for MUX-layer to route the packet out. */
100 info = cfpkt_info(pkt);
101 info->channel_id = service->layer.id;
102 /* To optimize alignment, we add up the size of CAIF header
103 * before payload.
104 */
105 info->hdr_len = 4;
106 info->dev_info = &service->dev_info;
107 ret = layr->dn->transmit(layr->dn, pkt);
108 if (ret < 0) {
109 u32 tmp32;
110 cfpkt_extr_head(pkt, &tmp32, 4);
111 }
112 return ret;
113}