linux/net/caif/cfutill.c
Sjur Braendeland b482cd2053 net-caif: add CAIF core protocol stack
CAIF generic protocol implementation. This layer is
somewhat generic in order to be able to use and test it outside
the Linux Kernel.

cfctrl.c     - CAIF control protocol layer
cfdbgl.c     - CAIF debug protocol layer
cfdgml.c     - CAIF datagram protocol layer
cffrml.c     - CAIF framing protocol layer
cfmuxl.c     - CAIF mux protocol layer
cfrfml.c     - CAIF remote file manager protocol layer
cfserl.c     - CAIF serial (fragmentation) protocol layer
cfsrvl.c     - CAIF generic service layer functions
cfutill.c    - CAIF utility protocol layer
cfveil.c     - CAIF AT protocol layer
cfvidl.c     - CAIF video protocol layer

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-30 19:08:46 -07:00

116 lines
3.2 KiB
C

/*
* Copyright (C) ST-Ericsson AB 2010
* Author: Sjur Brendeland/sjur.brandeland@stericsson.com
* License terms: GNU General Public License (GPL) version 2
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <net/caif/caif_layer.h>
#include <net/caif/cfsrvl.h>
#include <net/caif/cfpkt.h>
#define container_obj(layr) ((struct cfsrvl *) layr)
#define UTIL_PAYLOAD 0x00
#define UTIL_CMD_BIT 0x80
#define UTIL_REMOTE_SHUTDOWN 0x82
#define UTIL_FLOW_OFF 0x81
#define UTIL_FLOW_ON 0x80
#define UTIL_CTRL_PKT_SIZE 1
static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt);
static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt);
struct cflayer *cfutill_create(u8 channel_id, struct dev_info *dev_info)
{
struct cfsrvl *util = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
if (!util) {
pr_warning("CAIF: %s(): Out of memory\n", __func__);
return NULL;
}
caif_assert(offsetof(struct cfsrvl, layer) == 0);
memset(util, 0, sizeof(struct cfsrvl));
cfsrvl_init(util, channel_id, dev_info);
util->layer.receive = cfutill_receive;
util->layer.transmit = cfutill_transmit;
snprintf(util->layer.name, CAIF_LAYER_NAME_SZ - 1, "util1");
return &util->layer;
}
static int cfutill_receive(struct cflayer *layr, struct cfpkt *pkt)
{
u8 cmd = -1;
struct cfsrvl *service = container_obj(layr);
caif_assert(layr != NULL);
caif_assert(layr->up != NULL);
caif_assert(layr->up->receive != NULL);
caif_assert(layr->up->ctrlcmd != NULL);
if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
cfpkt_destroy(pkt);
return -EPROTO;
}
switch (cmd) {
case UTIL_PAYLOAD:
return layr->up->receive(layr->up, pkt);
case UTIL_FLOW_OFF:
layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
cfpkt_destroy(pkt);
return 0;
case UTIL_FLOW_ON:
layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
cfpkt_destroy(pkt);
return 0;
case UTIL_REMOTE_SHUTDOWN: /* Remote Shutdown Request */
pr_err("CAIF: %s(): REMOTE SHUTDOWN REQUEST RECEIVED\n",
__func__);
layr->ctrlcmd(layr, CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND, 0);
service->open = false;
cfpkt_destroy(pkt);
return 0;
default:
cfpkt_destroy(pkt);
pr_warning("CAIF: %s(): Unknown service control %d (0x%x)\n",
__func__, cmd, cmd);
return -EPROTO;
}
}
static int cfutill_transmit(struct cflayer *layr, struct cfpkt *pkt)
{
u8 zero = 0;
struct caif_payload_info *info;
int ret;
struct cfsrvl *service = container_obj(layr);
caif_assert(layr != NULL);
caif_assert(layr->dn != NULL);
caif_assert(layr->dn->transmit != NULL);
if (!cfsrvl_ready(service, &ret))
return ret;
if (cfpkt_getlen(pkt) > CAIF_MAX_PAYLOAD_SIZE) {
pr_err("CAIF: %s(): packet too large size=%d\n",
__func__, cfpkt_getlen(pkt));
return -EOVERFLOW;
}
cfpkt_add_head(pkt, &zero, 1);
/* Add info for MUX-layer to route the packet out. */
info = cfpkt_info(pkt);
info->channel_id = service->layer.id;
/*
* To optimize alignment, we add up the size of CAIF header before
* payload.
*/
info->hdr_len = 1;
info->dev_info = &service->dev_info;
ret = layr->dn->transmit(layr->dn, pkt);
if (ret < 0) {
u32 tmp32;
cfpkt_extr_head(pkt, &tmp32, 4);
}
return ret;
}