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
23static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt);
24static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt);
25
26struct 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
39static 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
75static 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);
98err:
99	cfpkt_destroy(pkt);
100	return ret;
101}
102