GNU Linux-libre 4.19.211-gnu1
[releases.git] / net / caif / cfveil.c
1 /*
2  * Copyright (C) ST-Ericsson AB 2010
3  * Author:      Sjur Brendeland
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/stddef.h>
10 #include <linux/slab.h>
11 #include <net/caif/caif_layer.h>
12 #include <net/caif/cfsrvl.h>
13 #include <net/caif/cfpkt.h>
14
15 #define VEI_PAYLOAD  0x00
16 #define VEI_CMD_BIT  0x80
17 #define VEI_FLOW_OFF 0x81
18 #define VEI_FLOW_ON  0x80
19 #define VEI_SET_PIN  0x82
20
21 #define container_obj(layr) container_of(layr, struct cfsrvl, layer)
22
23 static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt);
24 static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt);
25
26 struct cflayer *cfvei_create(u8 channel_id, struct dev_info *dev_info)
27 {
28         struct cfsrvl *vei = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
29         if (!vei)
30                 return NULL;
31         caif_assert(offsetof(struct cfsrvl, layer) == 0);
32         cfsrvl_init(vei, channel_id, dev_info, true);
33         vei->layer.receive = cfvei_receive;
34         vei->layer.transmit = cfvei_transmit;
35         snprintf(vei->layer.name, CAIF_LAYER_NAME_SZ - 1, "vei%d", channel_id);
36         return &vei->layer;
37 }
38
39 static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt)
40 {
41         u8 cmd;
42         int ret;
43         caif_assert(layr->up != NULL);
44         caif_assert(layr->receive != NULL);
45         caif_assert(layr->ctrlcmd != NULL);
46
47
48         if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
49                 pr_err("Packet is erroneous!\n");
50                 cfpkt_destroy(pkt);
51                 return -EPROTO;
52         }
53         switch (cmd) {
54         case VEI_PAYLOAD:
55                 ret = layr->up->receive(layr->up, pkt);
56                 return ret;
57         case VEI_FLOW_OFF:
58                 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
59                 cfpkt_destroy(pkt);
60                 return 0;
61         case VEI_FLOW_ON:
62                 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
63                 cfpkt_destroy(pkt);
64                 return 0;
65         case VEI_SET_PIN:       /* SET RS232 PIN */
66                 cfpkt_destroy(pkt);
67                 return 0;
68         default:                /* SET RS232 PIN */
69                 pr_warn("Unknown VEI control packet %d (0x%x)!\n", cmd, cmd);
70                 cfpkt_destroy(pkt);
71                 return -EPROTO;
72         }
73 }
74
75 static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt)
76 {
77         u8 tmp = 0;
78         struct caif_payload_info *info;
79         int ret;
80         struct cfsrvl *service = container_obj(layr);
81         if (!cfsrvl_ready(service, &ret))
82                 goto err;
83         caif_assert(layr->dn != NULL);
84         caif_assert(layr->dn->transmit != NULL);
85
86         if (cfpkt_add_head(pkt, &tmp, 1) < 0) {
87                 pr_err("Packet is erroneous!\n");
88                 ret = -EPROTO;
89                 goto err;
90         }
91
92         /* Add info-> for MUX-layer to route the packet out. */
93         info = cfpkt_info(pkt);
94         info->channel_id = service->layer.id;
95         info->hdr_len = 1;
96         info->dev_info = &service->dev_info;
97         return layr->dn->transmit(layr->dn, pkt);
98 err:
99         cfpkt_destroy(pkt);
100         return ret;
101 }