1 /*
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
7 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
8
9 #include <linux/kernel.h>
10 #include <linux/types.h>
11 #include <linux/slab.h>
12 #include <linux/errno.h>
13 #include <net/caif/caif_layer.h>
14 #include <net/caif/cfsrvl.h>
15 #include <net/caif/cfpkt.h>
16
17 #define container_obj(layr) ((struct cfsrvl *) layr)
18 #define UTIL_PAYLOAD 0x00
19 #define UTIL_CMD_BIT 0x80
20 #define UTIL_REMOTE_SHUTDOWN 0x82
21 #define UTIL_FLOW_OFF 0x81
22 #define UTIL_FLOW_ON 0x80
23
24 static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt);
25 static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt);
26
cfutill_create(u8 channel_id,struct dev_info * dev_info)27 struct cflayer *cfutill_create(u8 channel_id, struct dev_info *dev_info)
28 {
29 struct cfsrvl *util = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
30 if (!util) {
31 pr_warn("Out of memory\n");
32 return NULL;
33 }
34 caif_assert(offsetof(struct cfsrvl, layer) == 0);
35 memset(util, 0, sizeof(struct cfsrvl));
36 cfsrvl_init(util, channel_id, dev_info, true);
37 util->layer.receive = cfutill_receive;
38 util->layer.transmit = cfutill_transmit;
39 snprintf(util->layer.name, CAIF_LAYER_NAME_SZ - 1, "util1");
40 return &util->layer;
41 }
42
cfutill_receive(struct cflayer * layr,struct cfpkt * pkt)43 static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt)
44 {
45 u8 cmd = -1;
46 struct cfsrvl *service = container_obj(layr);
47 caif_assert(layr != NULL);
48 caif_assert(layr->up != NULL);
49 caif_assert(layr->up->receive != NULL);
50 caif_assert(layr->up->ctrlcmd != NULL);
51 if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
52 pr_err("Packet is erroneous!\n");
53 cfpkt_destroy(pkt);
54 return -EPROTO;
55 }
56
57 switch (cmd) {
58 case UTIL_PAYLOAD:
59 return layr->up->receive(layr->up, pkt);
60 case UTIL_FLOW_OFF:
61 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
62 cfpkt_destroy(pkt);
63 return 0;
64 case UTIL_FLOW_ON:
65 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
66 cfpkt_destroy(pkt);
67 return 0;
68 case UTIL_REMOTE_SHUTDOWN: /* Remote Shutdown Request */
69 pr_err("REMOTE SHUTDOWN REQUEST RECEIVED\n");
70 layr->ctrlcmd(layr, CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND, 0);
71 service->open = false;
72 cfpkt_destroy(pkt);
73 return 0;
74 default:
75 cfpkt_destroy(pkt);
76 pr_warn("Unknown service control %d (0x%x)\n", cmd, cmd);
77 return -EPROTO;
78 }
79 }
80
cfutill_transmit(struct cflayer * layr,struct cfpkt * pkt)81 static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt)
82 {
83 u8 zero = 0;
84 struct caif_payload_info *info;
85 int ret;
86 struct cfsrvl *service = container_obj(layr);
87 caif_assert(layr != NULL);
88 caif_assert(layr->dn != NULL);
89 caif_assert(layr->dn->transmit != NULL);
90 if (!cfsrvl_ready(service, &ret))
91 return ret;
92
93 cfpkt_add_head(pkt, &zero, 1);
94 /* Add info for MUX-layer to route the packet out. */
95 info = cfpkt_info(pkt);
96 info->channel_id = service->layer.id;
97 /*
98 * To optimize alignment, we add up the size of CAIF header before
99 * payload.
100 */
101 info->hdr_len = 1;
102 info->dev_info = &service->dev_info;
103 ret = layr->dn->transmit(layr->dn, pkt);
104 if (ret < 0) {
105 u32 tmp32;
106 cfpkt_extr_head(pkt, &tmp32, 4);
107 }
108 return ret;
109 }
110