1 /* 2 * Copyright (C) ST-Ericsson AB 2010 3 * Author: Sjur Brendeland/sjur.brandeland@stericsson.com 4 * License terms: GNU General Public License (GPL) version 2 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/types.h> 9 #include <linux/slab.h> 10 #include <linux/errno.h> 11 #include <net/caif/caif_layer.h> 12 #include <net/caif/cfsrvl.h> 13 #include <net/caif/cfpkt.h> 14 15 #define container_obj(layr) ((struct cfsrvl *) layr) 16 #define UTIL_PAYLOAD 0x00 17 #define UTIL_CMD_BIT 0x80 18 #define UTIL_REMOTE_SHUTDOWN 0x82 19 #define UTIL_FLOW_OFF 0x81 20 #define UTIL_FLOW_ON 0x80 21 #define UTIL_CTRL_PKT_SIZE 1 22 static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt); 23 static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt); 24 25 struct cflayer *cfutill_create(u8 channel_id, struct dev_info *dev_info) 26 { 27 struct cfsrvl *util = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC); 28 if (!util) { 29 pr_warning("CAIF: %s(): Out of memory\n", __func__); 30 return NULL; 31 } 32 caif_assert(offsetof(struct cfsrvl, layer) == 0); 33 memset(util, 0, sizeof(struct cfsrvl)); 34 cfsrvl_init(util, channel_id, dev_info, true); 35 util->layer.receive = cfutill_receive; 36 util->layer.transmit = cfutill_transmit; 37 snprintf(util->layer.name, CAIF_LAYER_NAME_SZ - 1, "util1"); 38 return &util->layer; 39 } 40 41 static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt) 42 { 43 u8 cmd = -1; 44 struct cfsrvl *service = container_obj(layr); 45 caif_assert(layr != NULL); 46 caif_assert(layr->up != NULL); 47 caif_assert(layr->up->receive != NULL); 48 caif_assert(layr->up->ctrlcmd != NULL); 49 if (cfpkt_extr_head(pkt, &cmd, 1) < 0) { 50 pr_err("CAIF: %s(): Packet is erroneous!\n", __func__); 51 cfpkt_destroy(pkt); 52 return -EPROTO; 53 } 54 55 switch (cmd) { 56 case UTIL_PAYLOAD: 57 return layr->up->receive(layr->up, pkt); 58 case UTIL_FLOW_OFF: 59 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0); 60 cfpkt_destroy(pkt); 61 return 0; 62 case UTIL_FLOW_ON: 63 layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0); 64 cfpkt_destroy(pkt); 65 return 0; 66 case UTIL_REMOTE_SHUTDOWN: /* Remote Shutdown Request */ 67 pr_err("CAIF: %s(): REMOTE SHUTDOWN REQUEST RECEIVED\n", 68 __func__); 69 layr->ctrlcmd(layr, CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND, 0); 70 service->open = false; 71 cfpkt_destroy(pkt); 72 return 0; 73 default: 74 cfpkt_destroy(pkt); 75 pr_warning("CAIF: %s(): Unknown service control %d (0x%x)\n", 76 __func__, cmd, cmd); 77 return -EPROTO; 78 } 79 } 80 81 static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt) 82 { 83 u8 zero = 0; 84 struct caif_payload_info *info; 85 int ret; 86 struct cfsrvl *service = container_obj(layr); 87 caif_assert(layr != NULL); 88 caif_assert(layr->dn != NULL); 89 caif_assert(layr->dn->transmit != NULL); 90 if (!cfsrvl_ready(service, &ret)) 91 return ret; 92 93 cfpkt_add_head(pkt, &zero, 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 ret = layr->dn->transmit(layr->dn, pkt); 104 if (ret < 0) { 105 u32 tmp32; 106 cfpkt_extr_head(pkt, &tmp32, 4); 107 } 108 return ret; 109 } 110