1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (C) ST-Ericsson AB 2010
4*4882a593Smuzhiyun * Author: Sjur Brendeland
5*4882a593Smuzhiyun */
6*4882a593Smuzhiyun
7*4882a593Smuzhiyun #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/kernel.h>
10*4882a593Smuzhiyun #include <linux/types.h>
11*4882a593Smuzhiyun #include <linux/slab.h>
12*4882a593Smuzhiyun #include <linux/errno.h>
13*4882a593Smuzhiyun #include <net/caif/caif_layer.h>
14*4882a593Smuzhiyun #include <net/caif/cfsrvl.h>
15*4882a593Smuzhiyun #include <net/caif/cfpkt.h>
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun #define container_obj(layr) ((struct cfsrvl *) layr)
18*4882a593Smuzhiyun #define UTIL_PAYLOAD 0x00
19*4882a593Smuzhiyun #define UTIL_CMD_BIT 0x80
20*4882a593Smuzhiyun #define UTIL_REMOTE_SHUTDOWN 0x82
21*4882a593Smuzhiyun #define UTIL_FLOW_OFF 0x81
22*4882a593Smuzhiyun #define UTIL_FLOW_ON 0x80
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt);
25*4882a593Smuzhiyun static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt);
26*4882a593Smuzhiyun
cfutill_create(u8 channel_id,struct dev_info * dev_info)27*4882a593Smuzhiyun struct cflayer *cfutill_create(u8 channel_id, struct dev_info *dev_info)
28*4882a593Smuzhiyun {
29*4882a593Smuzhiyun struct cfsrvl *util = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
30*4882a593Smuzhiyun if (!util)
31*4882a593Smuzhiyun return NULL;
32*4882a593Smuzhiyun caif_assert(offsetof(struct cfsrvl, layer) == 0);
33*4882a593Smuzhiyun cfsrvl_init(util, channel_id, dev_info, true);
34*4882a593Smuzhiyun util->layer.receive = cfutill_receive;
35*4882a593Smuzhiyun util->layer.transmit = cfutill_transmit;
36*4882a593Smuzhiyun snprintf(util->layer.name, CAIF_LAYER_NAME_SZ, "util1");
37*4882a593Smuzhiyun return &util->layer;
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun
cfutill_receive(struct cflayer * layr,struct cfpkt * pkt)40*4882a593Smuzhiyun static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun u8 cmd = -1;
43*4882a593Smuzhiyun struct cfsrvl *service = container_obj(layr);
44*4882a593Smuzhiyun caif_assert(layr != NULL);
45*4882a593Smuzhiyun caif_assert(layr->up != NULL);
46*4882a593Smuzhiyun caif_assert(layr->up->receive != NULL);
47*4882a593Smuzhiyun caif_assert(layr->up->ctrlcmd != NULL);
48*4882a593Smuzhiyun if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
49*4882a593Smuzhiyun pr_err("Packet is erroneous!\n");
50*4882a593Smuzhiyun cfpkt_destroy(pkt);
51*4882a593Smuzhiyun return -EPROTO;
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun switch (cmd) {
55*4882a593Smuzhiyun case UTIL_PAYLOAD:
56*4882a593Smuzhiyun return layr->up->receive(layr->up, pkt);
57*4882a593Smuzhiyun case UTIL_FLOW_OFF:
58*4882a593Smuzhiyun layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
59*4882a593Smuzhiyun cfpkt_destroy(pkt);
60*4882a593Smuzhiyun return 0;
61*4882a593Smuzhiyun case UTIL_FLOW_ON:
62*4882a593Smuzhiyun layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
63*4882a593Smuzhiyun cfpkt_destroy(pkt);
64*4882a593Smuzhiyun return 0;
65*4882a593Smuzhiyun case UTIL_REMOTE_SHUTDOWN: /* Remote Shutdown Request */
66*4882a593Smuzhiyun pr_err("REMOTE SHUTDOWN REQUEST RECEIVED\n");
67*4882a593Smuzhiyun layr->ctrlcmd(layr, CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND, 0);
68*4882a593Smuzhiyun service->open = false;
69*4882a593Smuzhiyun cfpkt_destroy(pkt);
70*4882a593Smuzhiyun return 0;
71*4882a593Smuzhiyun default:
72*4882a593Smuzhiyun cfpkt_destroy(pkt);
73*4882a593Smuzhiyun pr_warn("Unknown service control %d (0x%x)\n", cmd, cmd);
74*4882a593Smuzhiyun return -EPROTO;
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun
cfutill_transmit(struct cflayer * layr,struct cfpkt * pkt)78*4882a593Smuzhiyun static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt)
79*4882a593Smuzhiyun {
80*4882a593Smuzhiyun u8 zero = 0;
81*4882a593Smuzhiyun struct caif_payload_info *info;
82*4882a593Smuzhiyun int ret;
83*4882a593Smuzhiyun struct cfsrvl *service = container_obj(layr);
84*4882a593Smuzhiyun caif_assert(layr != NULL);
85*4882a593Smuzhiyun caif_assert(layr->dn != NULL);
86*4882a593Smuzhiyun caif_assert(layr->dn->transmit != NULL);
87*4882a593Smuzhiyun
88*4882a593Smuzhiyun if (!cfsrvl_ready(service, &ret)) {
89*4882a593Smuzhiyun cfpkt_destroy(pkt);
90*4882a593Smuzhiyun return ret;
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun cfpkt_add_head(pkt, &zero, 1);
94*4882a593Smuzhiyun /* Add info for MUX-layer to route the packet out. */
95*4882a593Smuzhiyun info = cfpkt_info(pkt);
96*4882a593Smuzhiyun info->channel_id = service->layer.id;
97*4882a593Smuzhiyun /*
98*4882a593Smuzhiyun * To optimize alignment, we add up the size of CAIF header before
99*4882a593Smuzhiyun * payload.
100*4882a593Smuzhiyun */
101*4882a593Smuzhiyun info->hdr_len = 1;
102*4882a593Smuzhiyun info->dev_info = &service->dev_info;
103*4882a593Smuzhiyun return layr->dn->transmit(layr->dn, pkt);
104*4882a593Smuzhiyun }
105