1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) ST-Ericsson AB 2010 |
4 | * Author: Sjur Brendeland |
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 | |
27 | struct cflayer *cfutill_create(u8 channel_id, struct dev_info *dev_info) |
28 | { |
29 | struct cfsrvl *util = kzalloc(size: sizeof(struct cfsrvl), GFP_ATOMIC); |
30 | if (!util) |
31 | return NULL; |
32 | caif_assert(offsetof(struct cfsrvl, layer) == 0); |
33 | cfsrvl_init(service: util, channel_id, dev_info, supports_flowctrl: true); |
34 | util->layer.receive = cfutill_receive; |
35 | util->layer.transmit = cfutill_transmit; |
36 | snprintf(buf: util->layer.name, CAIF_LAYER_NAME_SZ, fmt: "util1" ); |
37 | return &util->layer; |
38 | } |
39 | |
40 | static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt) |
41 | { |
42 | u8 cmd = -1; |
43 | struct cfsrvl *service = container_obj(layr); |
44 | caif_assert(layr != NULL); |
45 | caif_assert(layr->up != NULL); |
46 | caif_assert(layr->up->receive != NULL); |
47 | caif_assert(layr->up->ctrlcmd != NULL); |
48 | if (cfpkt_extr_head(pkt, data: &cmd, len: 1) < 0) { |
49 | pr_err("Packet is erroneous!\n" ); |
50 | cfpkt_destroy(pkt); |
51 | return -EPROTO; |
52 | } |
53 | |
54 | switch (cmd) { |
55 | case UTIL_PAYLOAD: |
56 | return layr->up->receive(layr->up, pkt); |
57 | case UTIL_FLOW_OFF: |
58 | layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0); |
59 | cfpkt_destroy(pkt); |
60 | return 0; |
61 | case UTIL_FLOW_ON: |
62 | layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0); |
63 | cfpkt_destroy(pkt); |
64 | return 0; |
65 | case UTIL_REMOTE_SHUTDOWN: /* Remote Shutdown Request */ |
66 | pr_err("REMOTE SHUTDOWN REQUEST RECEIVED\n" ); |
67 | layr->ctrlcmd(layr, CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND, 0); |
68 | service->open = false; |
69 | cfpkt_destroy(pkt); |
70 | return 0; |
71 | default: |
72 | cfpkt_destroy(pkt); |
73 | pr_warn("Unknown service control %d (0x%x)\n" , cmd, cmd); |
74 | return -EPROTO; |
75 | } |
76 | } |
77 | |
78 | static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt) |
79 | { |
80 | u8 zero = 0; |
81 | struct caif_payload_info *info; |
82 | int ret; |
83 | struct cfsrvl *service = container_obj(layr); |
84 | caif_assert(layr != NULL); |
85 | caif_assert(layr->dn != NULL); |
86 | caif_assert(layr->dn->transmit != NULL); |
87 | |
88 | if (!cfsrvl_ready(service, err: &ret)) { |
89 | cfpkt_destroy(pkt); |
90 | return ret; |
91 | } |
92 | |
93 | cfpkt_add_head(pkt, data: &zero, len: 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 | return layr->dn->transmit(layr->dn, pkt); |
104 | } |
105 | |