LXR linux/net/caif/cfveil.c

   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/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, "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