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>

net/caif/cfdbgl.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/stddef.h>
+#include <linux/slab.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfsrvl.h>
+#include <net/caif/cfpkt.h>
+
+static int cfdbgl_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cfdbgl_transmit(struct cflayer *layr, struct cfpkt *pkt);
+
+struct cflayer *cfdbgl_create(u8 channel_id, struct dev_info *dev_info)
+{
+	struct cfsrvl *dbg = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+	if (!dbg) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	caif_assert(offsetof(struct cfsrvl, layer) == 0);
+	memset(dbg, 0, sizeof(struct cfsrvl));
+	cfsrvl_init(dbg, channel_id, dev_info);
+	dbg->layer.receive = cfdbgl_receive;
+	dbg->layer.transmit = cfdbgl_transmit;
+	snprintf(dbg->layer.name, CAIF_LAYER_NAME_SZ - 1, "dbg%d", channel_id);
+	return &dbg->layer;
+}
+
+static int cfdbgl_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+	return layr->up->receive(layr->up, pkt);
+}
+
+static int cfdbgl_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+	return layr->dn->transmit(layr->dn, pkt);
+}

net/caif/cfdgml.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/stddef.h>
+#include <linux/spinlock.h>
+#include <linux/slab.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 DGM_CMD_BIT  0x80
+#define DGM_FLOW_OFF 0x81
+#define DGM_FLOW_ON  0x80
+#define DGM_CTRL_PKT_SIZE 1
+
+static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt);
+
+struct cflayer *cfdgml_create(u8 channel_id, struct dev_info *dev_info)
+{
+	struct cfsrvl *dgm = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+	if (!dgm) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	caif_assert(offsetof(struct cfsrvl, layer) == 0);
+	memset(dgm, 0, sizeof(struct cfsrvl));
+	cfsrvl_init(dgm, channel_id, dev_info);
+	dgm->layer.receive = cfdgml_receive;
+	dgm->layer.transmit = cfdgml_transmit;
+	snprintf(dgm->layer.name, CAIF_LAYER_NAME_SZ - 1, "dgm%d", channel_id);
+	dgm->layer.name[CAIF_LAYER_NAME_SZ - 1] = '\0';
+	return &dgm->layer;
+}
+
+static int cfdgml_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u8 cmd = -1;
+	u8 dgmhdr[3];
+	int ret;
+	caif_assert(layr->up != NULL);
+	caif_assert(layr->receive != NULL);
+	caif_assert(layr->ctrlcmd != NULL);
+
+	if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
+		pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+		cfpkt_destroy(pkt);
+		return -EPROTO;
+	}
+
+	if ((cmd & DGM_CMD_BIT) == 0) {
+		if (cfpkt_extr_head(pkt, &dgmhdr, 3) < 0) {
+			pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+			cfpkt_destroy(pkt);
+			return -EPROTO;
+		}
+		ret = layr->up->receive(layr->up, pkt);
+		return ret;
+	}
+
+	switch (cmd) {
+	case DGM_FLOW_OFF:	/* FLOW OFF */
+		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
+		cfpkt_destroy(pkt);
+		return 0;
+	case DGM_FLOW_ON:	/* FLOW ON */
+		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
+		cfpkt_destroy(pkt);
+		return 0;
+	default:
+		cfpkt_destroy(pkt);
+		pr_info("CAIF: %s(): Unknown datagram control %d (0x%x)\n",
+			__func__, cmd, cmd);
+		return -EPROTO;
+	}
+}
+
+static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u32 zero = 0;
+	struct caif_payload_info *info;
+	struct cfsrvl *service = container_obj(layr);
+	int ret;
+	if (!cfsrvl_ready(service, &ret))
+		return ret;
+
+	cfpkt_add_head(pkt, &zero, 4);
+
+	/* 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 = 4;
+	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;
+}

net/caif/cffrml.c

+/*
+ * CAIF Framing Layer.
+ *
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author:	Sjur Brendeland/sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/stddef.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/crc-ccitt.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/cffrml.h>
+
+#define container_obj(layr) container_of(layr, struct cffrml, layer)
+
+struct cffrml {
+	struct cflayer layer;
+	bool dofcs;		/* !< FCS active */
+};
+
+static int cffrml_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cffrml_transmit(struct cflayer *layr, struct cfpkt *pkt);
+static void cffrml_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+				int phyid);
+
+static u32 cffrml_rcv_error;
+static u32 cffrml_rcv_checsum_error;
+struct cflayer *cffrml_create(u16 phyid, bool use_fcs)
+{
+	struct cffrml *this = kmalloc(sizeof(struct cffrml), GFP_ATOMIC);
+	if (!this) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	caif_assert(offsetof(struct cffrml, layer) == 0);
+
+	memset(this, 0, sizeof(struct cflayer));
+	this->layer.receive = cffrml_receive;
+	this->layer.transmit = cffrml_transmit;
+	this->layer.ctrlcmd = cffrml_ctrlcmd;
+	snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "frm%d", phyid);
+	this->dofcs = use_fcs;
+	this->layer.id = phyid;
+	return (struct cflayer *) this;
+}
+
+void cffrml_set_uplayer(struct cflayer *this, struct cflayer *up)
+{
+	this->up = up;
+}
+
+void cffrml_set_dnlayer(struct cflayer *this, struct cflayer *dn)
+{
+	this->dn = dn;
+}
+
+static u16 cffrml_checksum(u16 chks, void *buf, u16 len)
+{
+	/* FIXME: FCS should be moved to glue in order to use OS-Specific
+	 * solutions
+	 */
+	return crc_ccitt(chks, buf, len);
+}
+
+static int cffrml_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u16 tmp;
+	u16 len;
+	u16 hdrchks;
+	u16 pktchks;
+	struct cffrml *this;
+	this = container_obj(layr);
+
+	cfpkt_extr_head(pkt, &tmp, 2);
+	len = le16_to_cpu(tmp);
+
+	/* Subtract for FCS on length if FCS is not used. */
+	if (!this->dofcs)
+		len -= 2;
+
+	if (cfpkt_setlen(pkt, len) < 0) {
+		++cffrml_rcv_error;
+		pr_err("CAIF: %s():Framing length error (%d)\n", __func__, len);
+		cfpkt_destroy(pkt);
+		return -EPROTO;
+	}
+	/*
+	 * Don't do extract if FCS is false, rather do setlen - then we don't
+	 * get a cache-miss.
+	 */
+	if (this->dofcs) {
+		cfpkt_extr_trail(pkt, &tmp, 2);
+		hdrchks = le16_to_cpu(tmp);
+		pktchks = cfpkt_iterate(pkt, cffrml_checksum, 0xffff);
+		if (pktchks != hdrchks) {
+			cfpkt_add_trail(pkt, &tmp, 2);
+			++cffrml_rcv_error;
+			++cffrml_rcv_checsum_error;
+			pr_info("CAIF: %s(): Frame checksum error "
+				"(0x%x != 0x%x)\n", __func__, hdrchks, pktchks);
+			return -EILSEQ;
+		}
+	}
+	if (cfpkt_erroneous(pkt)) {
+		++cffrml_rcv_error;
+		pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+		cfpkt_destroy(pkt);
+		return -EPROTO;
+	}
+	return layr->up->receive(layr->up, pkt);
+}
+
+static int cffrml_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+	int tmp;
+	u16 chks;
+	u16 len;
+	int ret;
+	struct cffrml *this = container_obj(layr);
+	if (this->dofcs) {
+		chks = cfpkt_iterate(pkt, cffrml_checksum, 0xffff);
+		tmp = cpu_to_le16(chks);
+		cfpkt_add_trail(pkt, &tmp, 2);
+	} else {
+		cfpkt_pad_trail(pkt, 2);
+	}
+	len = cfpkt_getlen(pkt);
+	tmp = cpu_to_le16(len);
+	cfpkt_add_head(pkt, &tmp, 2);
+	cfpkt_info(pkt)->hdr_len += 2;
+	if (cfpkt_erroneous(pkt)) {
+		pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+		return -EPROTO;
+	}
+	ret = layr->dn->transmit(layr->dn, pkt);
+	if (ret < 0) {
+		/* Remove header on faulty packet. */
+		cfpkt_extr_head(pkt, &tmp, 2);
+	}
+	return ret;
+}
+
+static void cffrml_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+					int phyid)
+{
+	if (layr->up->ctrlcmd)
+		layr->up->ctrlcmd(layr->up, ctrl, layr->id);
+}

net/caif/cfmuxl.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/stddef.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/cfmuxl.h>
+#include <net/caif/cfsrvl.h>
+#include <net/caif/cffrml.h>
+
+#define container_obj(layr) container_of(layr, struct cfmuxl, layer)
+
+#define CAIF_CTRL_CHANNEL 0
+#define UP_CACHE_SIZE 8
+#define DN_CACHE_SIZE 8
+
+struct cfmuxl {
+	struct cflayer layer;
+	struct list_head srvl_list;
+	struct list_head frml_list;
+	struct cflayer *up_cache[UP_CACHE_SIZE];
+	struct cflayer *dn_cache[DN_CACHE_SIZE];
+	/*
+	 * Set when inserting or removing downwards layers.
+	 */
+	spinlock_t transmit_lock;
+
+	/*
+	 * Set when inserting or removing upwards layers.
+	 */
+	spinlock_t receive_lock;
+
+};
+
+static int cfmuxl_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cfmuxl_transmit(struct cflayer *layr, struct cfpkt *pkt);
+static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+				int phyid);
+static struct cflayer *get_up(struct cfmuxl *muxl, u16 id);
+
+struct cflayer *cfmuxl_create(void)
+{
+	struct cfmuxl *this = kmalloc(sizeof(struct cfmuxl), GFP_ATOMIC);
+	if (!this)
+		return NULL;
+	memset(this, 0, sizeof(*this));
+	this->layer.receive = cfmuxl_receive;
+	this->layer.transmit = cfmuxl_transmit;
+	this->layer.ctrlcmd = cfmuxl_ctrlcmd;
+	INIT_LIST_HEAD(&this->srvl_list);
+	INIT_LIST_HEAD(&this->frml_list);
+	spin_lock_init(&this->transmit_lock);
+	spin_lock_init(&this->receive_lock);
+	snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "mux");
+	return &this->layer;
+}
+
+int cfmuxl_set_uplayer(struct cflayer *layr, struct cflayer *up, u8 linkid)
+{
+	struct cfmuxl *muxl = container_obj(layr);
+	spin_lock(&muxl->receive_lock);
+	list_add(&up->node, &muxl->srvl_list);
+	spin_unlock(&muxl->receive_lock);
+	return 0;
+}
+
+bool cfmuxl_is_phy_inuse(struct cflayer *layr, u8 phyid)
+{
+	struct list_head *node;
+	struct cflayer *layer;
+	struct cfmuxl *muxl = container_obj(layr);
+	bool match = false;
+	spin_lock(&muxl->receive_lock);
+
+	list_for_each(node, &muxl->srvl_list) {
+		layer = list_entry(node, struct cflayer, node);
+		if (cfsrvl_phyid_match(layer, phyid)) {
+			match = true;
+			break;
+		}
+
+	}
+	spin_unlock(&muxl->receive_lock);
+	return match;
+}
+
+u8 cfmuxl_get_phyid(struct cflayer *layr, u8 channel_id)
+{
+	struct cflayer *up;
+	int phyid;
+	struct cfmuxl *muxl = container_obj(layr);
+	spin_lock(&muxl->receive_lock);
+	up = get_up(muxl, channel_id);
+	if (up != NULL)
+		phyid = cfsrvl_getphyid(up);
+	else
+		phyid = 0;
+	spin_unlock(&muxl->receive_lock);
+	return phyid;
+}
+
+int cfmuxl_set_dnlayer(struct cflayer *layr, struct cflayer *dn, u8 phyid)
+{
+	struct cfmuxl *muxl = (struct cfmuxl *) layr;
+	spin_lock(&muxl->transmit_lock);
+	list_add(&dn->node, &muxl->frml_list);
+	spin_unlock(&muxl->transmit_lock);
+	return 0;
+}
+
+static struct cflayer *get_from_id(struct list_head *list, u16 id)
+{
+	struct list_head *node;
+	struct cflayer *layer;
+	list_for_each(node, list) {
+		layer = list_entry(node, struct cflayer, node);
+		if (layer->id == id)
+			return layer;
+	}
+	return NULL;
+}
+
+struct cflayer *cfmuxl_remove_dnlayer(struct cflayer *layr, u8 phyid)
+{
+	struct cfmuxl *muxl = container_obj(layr);
+	struct cflayer *dn;
+	spin_lock(&muxl->transmit_lock);
+	memset(muxl->dn_cache, 0, sizeof(muxl->dn_cache));
+	dn = get_from_id(&muxl->frml_list, phyid);
+	if (dn == NULL) {
+		spin_unlock(&muxl->transmit_lock);
+		return NULL;
+	}
+	list_del(&dn->node);
+	caif_assert(dn != NULL);
+	spin_unlock(&muxl->transmit_lock);
+	return dn;
+}
+
+/* Invariant: lock is taken */
+static struct cflayer *get_up(struct cfmuxl *muxl, u16 id)
+{
+	struct cflayer *up;
+	int idx = id % UP_CACHE_SIZE;
+	up = muxl->up_cache[idx];
+	if (up == NULL || up->id != id) {
+		up = get_from_id(&muxl->srvl_list, id);
+		muxl->up_cache[idx] = up;
+	}
+	return up;
+}
+
+/* Invariant: lock is taken */
+static struct cflayer *get_dn(struct cfmuxl *muxl, struct dev_info *dev_info)
+{
+	struct cflayer *dn;
+	int idx = dev_info->id % DN_CACHE_SIZE;
+	dn = muxl->dn_cache[idx];
+	if (dn == NULL || dn->id != dev_info->id) {
+		dn = get_from_id(&muxl->frml_list, dev_info->id);
+		muxl->dn_cache[idx] = dn;
+	}
+	return dn;
+}
+
+struct cflayer *cfmuxl_remove_uplayer(struct cflayer *layr, u8 id)
+{
+	struct cflayer *up;
+	struct cfmuxl *muxl = container_obj(layr);
+	spin_lock(&muxl->receive_lock);
+	up = get_up(muxl, id);
+	memset(muxl->up_cache, 0, sizeof(muxl->up_cache));
+	list_del(&up->node);
+	spin_unlock(&muxl->receive_lock);
+	return up;
+}
+
+static int cfmuxl_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+	int ret;
+	struct cfmuxl *muxl = container_obj(layr);
+	u8 id;
+	struct cflayer *up;
+	if (cfpkt_extr_head(pkt, &id, 1) < 0) {
+		pr_err("CAIF: %s(): erroneous Caif Packet\n", __func__);
+		cfpkt_destroy(pkt);
+		return -EPROTO;
+	}
+
+	spin_lock(&muxl->receive_lock);
+	up = get_up(muxl, id);
+	spin_unlock(&muxl->receive_lock);
+	if (up == NULL) {
+		pr_info("CAIF: %s():Received data on unknown link ID = %d "
+			"(0x%x)	 up == NULL", __func__, id, id);
+		cfpkt_destroy(pkt);
+		/*
+		 * Don't return ERROR, since modem misbehaves and sends out
+		 * flow on before linksetup response.
+		 */
+		return /* CFGLU_EPROT; */ 0;
+	}
+
+	ret = up->receive(up, pkt);
+	return ret;
+}
+
+static int cfmuxl_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+	int ret;
+	struct cfmuxl *muxl = container_obj(layr);
+	u8 linkid;
+	struct cflayer *dn;
+	struct caif_payload_info *info = cfpkt_info(pkt);
+	dn = get_dn(muxl, cfpkt_info(pkt)->dev_info);
+	if (dn == NULL) {
+		pr_warning("CAIF: %s(): Send data on unknown phy "
+			   "ID = %d (0x%x)\n",
+			   __func__, info->dev_info->id, info->dev_info->id);
+		return -ENOTCONN;
+	}
+	info->hdr_len += 1;
+	linkid = info->channel_id;
+	cfpkt_add_head(pkt, &linkid, 1);
+	ret = dn->transmit(dn, pkt);
+	/* Remove MUX protocol header upon error. */
+	if (ret < 0)
+		cfpkt_extr_head(pkt, &linkid, 1);
+	return ret;
+}
+
+static void cfmuxl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+				int phyid)
+{
+	struct cfmuxl *muxl = container_obj(layr);
+	struct list_head *node;
+	struct cflayer *layer;
+	list_for_each(node, &muxl->srvl_list) {
+		layer = list_entry(node, struct cflayer, node);
+		if (cfsrvl_phyid_match(layer, phyid))
+			layer->ctrlcmd(layer, ctrl, phyid);
+	}
+}

net/caif/cfrfml.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/stddef.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfsrvl.h>
+#include <net/caif/cfpkt.h>
+
+#define container_obj(layr) container_of(layr, struct cfsrvl, layer)
+
+#define RFM_SEGMENTATION_BIT 0x01
+#define RFM_PAYLOAD  0x00
+#define RFM_CMD_BIT  0x80
+#define RFM_FLOW_OFF 0x81
+#define RFM_FLOW_ON  0x80
+#define RFM_SET_PIN  0x82
+#define RFM_CTRL_PKT_SIZE 1
+
+static int cfrfml_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cfrfml_transmit(struct cflayer *layr, struct cfpkt *pkt);
+static int cfservl_modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl);
+
+struct cflayer *cfrfml_create(u8 channel_id, struct dev_info *dev_info)
+{
+	struct cfsrvl *rfm = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+	if (!rfm) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	caif_assert(offsetof(struct cfsrvl, layer) == 0);
+	memset(rfm, 0, sizeof(struct cfsrvl));
+	cfsrvl_init(rfm, channel_id, dev_info);
+	rfm->layer.modemcmd = cfservl_modemcmd;
+	rfm->layer.receive = cfrfml_receive;
+	rfm->layer.transmit = cfrfml_transmit;
+	snprintf(rfm->layer.name, CAIF_LAYER_NAME_SZ, "rfm%d", channel_id);
+	return &rfm->layer;
+}
+
+static int cfservl_modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl)
+{
+       return -EPROTO;
+}
+
+static int cfrfml_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u8 tmp;
+	bool segmented;
+	int ret;
+	caif_assert(layr->up != NULL);
+	caif_assert(layr->receive != NULL);
+
+	/*
+	 * RFM is taking care of segmentation and stripping of
+	 * segmentation bit.
+	 */
+	if (cfpkt_extr_head(pkt, &tmp, 1) < 0) {
+		pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+		cfpkt_destroy(pkt);
+		return -EPROTO;
+	}
+	segmented = tmp & RFM_SEGMENTATION_BIT;
+	caif_assert(!segmented);
+
+	ret = layr->up->receive(layr->up, pkt);
+	return ret;
+}
+
+static int cfrfml_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u8 tmp = 0;
+	int ret;
+	struct cfsrvl *service = container_obj(layr);
+
+	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;
+	}
+	if (cfpkt_add_head(pkt, &tmp, 1) < 0) {
+		pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+		return -EPROTO;
+	}
+
+	/* Add info for MUX-layer to route the packet out. */
+	cfpkt_info(pkt)->channel_id = service->layer.id;
+	/*
+	 * To optimize alignment, we add up the size of CAIF header before
+	 * payload.
+	 */
+	cfpkt_info(pkt)->hdr_len = 1;
+	cfpkt_info(pkt)->dev_info = &service->dev_info;
+	ret = layr->dn->transmit(layr->dn, pkt);
+	if (ret < 0)
+		cfpkt_extr_head(pkt, &tmp, 1);
+	return ret;
+}

net/caif/cfserl.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/stddef.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/cfserl.h>
+
+#define container_obj(layr) ((struct cfserl *) layr)
+
+#define CFSERL_STX 0x02
+#define CAIF_MINIUM_PACKET_SIZE 4
+struct cfserl {
+	struct cflayer layer;
+	struct cfpkt *incomplete_frm;
+	/* Protects parallel processing of incoming packets */
+	spinlock_t sync;
+	bool usestx;
+};
+#define STXLEN(layr) (layr->usestx ? 1 : 0)
+
+static int cfserl_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cfserl_transmit(struct cflayer *layr, struct cfpkt *pkt);
+static void cfserl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+				int phyid);
+
+struct cflayer *cfserl_create(int type, int instance, bool use_stx)
+{
+	struct cfserl *this = kmalloc(sizeof(struct cfserl), GFP_ATOMIC);
+	if (!this) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	caif_assert(offsetof(struct cfserl, layer) == 0);
+	memset(this, 0, sizeof(struct cfserl));
+	this->layer.receive = cfserl_receive;
+	this->layer.transmit = cfserl_transmit;
+	this->layer.ctrlcmd = cfserl_ctrlcmd;
+	this->layer.type = type;
+	this->usestx = use_stx;
+	spin_lock_init(&this->sync);
+	snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "ser1");
+	return &this->layer;
+}
+
+static int cfserl_receive(struct cflayer *l, struct cfpkt *newpkt)
+{
+	struct cfserl *layr = container_obj(l);
+	u16 pkt_len;
+	struct cfpkt *pkt = NULL;
+	struct cfpkt *tail_pkt = NULL;
+	u8 tmp8;
+	u16 tmp;
+	u8 stx = CFSERL_STX;
+	int ret;
+	u16 expectlen = 0;
+	caif_assert(newpkt != NULL);
+	spin_lock(&layr->sync);
+
+	if (layr->incomplete_frm != NULL) {
+
+		layr->incomplete_frm =
+		    cfpkt_append(layr->incomplete_frm, newpkt, expectlen);
+		pkt = layr->incomplete_frm;
+	} else {
+		pkt = newpkt;
+	}
+	layr->incomplete_frm = NULL;
+
+	do {
+		/* Search for STX at start of pkt if STX is used */
+		if (layr->usestx) {
+			cfpkt_extr_head(pkt, &tmp8, 1);
+			if (tmp8 != CFSERL_STX) {
+				while (cfpkt_more(pkt)
+				       && tmp8 != CFSERL_STX) {
+					cfpkt_extr_head(pkt, &tmp8, 1);
+				}
+				if (!cfpkt_more(pkt)) {
+					cfpkt_destroy(pkt);
+					layr->incomplete_frm = NULL;
+					spin_unlock(&layr->sync);
+					return -EPROTO;
+				}
+			}
+		}
+
+		pkt_len = cfpkt_getlen(pkt);
+
+		/*
+		 *  pkt_len is the accumulated length of the packet data
+		 *  we have received so far.
+		 *  Exit if frame doesn't hold length.
+		 */
+
+		if (pkt_len < 2) {
+			if (layr->usestx)
+				cfpkt_add_head(pkt, &stx, 1);
+			layr->incomplete_frm = pkt;
+			spin_unlock(&layr->sync);
+			return 0;
+		}
+
+		/*
+		 *  Find length of frame.
+		 *  expectlen is the length we need for a full frame.
+		 */
+		cfpkt_peek_head(pkt, &tmp, 2);
+		expectlen = le16_to_cpu(tmp) + 2;
+		/*
+		 * Frame error handling
+		 */
+		if (expectlen < CAIF_MINIUM_PACKET_SIZE
+		    || expectlen > CAIF_MAX_FRAMESIZE) {
+			if (!layr->usestx) {
+				if (pkt != NULL)
+					cfpkt_destroy(pkt);
+				layr->incomplete_frm = NULL;
+				expectlen = 0;
+				spin_unlock(&layr->sync);
+				return -EPROTO;
+			}
+			continue;
+		}
+
+		if (pkt_len < expectlen) {
+			/* Too little received data */
+			if (layr->usestx)
+				cfpkt_add_head(pkt, &stx, 1);
+			layr->incomplete_frm = pkt;
+			spin_unlock(&layr->sync);
+			return 0;
+		}
+
+		/*
+		 * Enough data for at least one frame.
+		 * Split the frame, if too long
+		 */
+		if (pkt_len > expectlen)
+			tail_pkt = cfpkt_split(pkt, expectlen);
+		else
+			tail_pkt = NULL;
+
+		/* Send the first part of packet upwards.*/
+		spin_unlock(&layr->sync);
+		ret = layr->layer.up->receive(layr->layer.up, pkt);
+		spin_lock(&layr->sync);
+		if (ret == -EILSEQ) {
+			if (layr->usestx) {
+				if (tail_pkt != NULL)
+					pkt = cfpkt_append(pkt, tail_pkt, 0);
+
+				/* Start search for next STX if frame failed */
+				continue;
+			} else {
+				cfpkt_destroy(pkt);
+				pkt = NULL;
+			}
+		}
+
+		pkt = tail_pkt;
+
+	} while (pkt != NULL);
+
+	spin_unlock(&layr->sync);
+	return 0;
+}
+
+static int cfserl_transmit(struct cflayer *layer, struct cfpkt *newpkt)
+{
+	struct cfserl *layr = container_obj(layer);
+	int ret;
+	u8 tmp8 = CFSERL_STX;
+	if (layr->usestx)
+		cfpkt_add_head(newpkt, &tmp8, 1);
+	ret = layer->dn->transmit(layer->dn, newpkt);
+	if (ret < 0)
+		cfpkt_extr_head(newpkt, &tmp8, 1);
+
+	return ret;
+}
+
+static void cfserl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+				int phyid)
+{
+	layr->up->ctrlcmd(layr->up, ctrl, phyid);
+}

net/caif/cfsrvl.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/errno.h>
+#include <linux/slab.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfsrvl.h>
+#include <net/caif/cfpkt.h>
+
+#define SRVL_CTRL_PKT_SIZE 1
+#define SRVL_FLOW_OFF 0x81
+#define SRVL_FLOW_ON  0x80
+#define SRVL_SET_PIN  0x82
+#define SRVL_CTRL_PKT_SIZE 1
+
+#define container_obj(layr) container_of(layr, struct cfsrvl, layer)
+
+static void cfservl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+				int phyid)
+{
+	struct cfsrvl *service = container_obj(layr);
+	caif_assert(layr->up != NULL);
+	caif_assert(layr->up->ctrlcmd != NULL);
+	switch (ctrl) {
+	case CAIF_CTRLCMD_INIT_RSP:
+		service->open = true;
+		layr->up->ctrlcmd(layr->up, ctrl, phyid);
+		break;
+	case CAIF_CTRLCMD_DEINIT_RSP:
+	case CAIF_CTRLCMD_INIT_FAIL_RSP:
+		service->open = false;
+		layr->up->ctrlcmd(layr->up, ctrl, phyid);
+		break;
+	case _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND:
+		if (phyid != service->dev_info.id)
+			break;
+		if (service->modem_flow_on)
+			layr->up->ctrlcmd(layr->up,
+					  CAIF_CTRLCMD_FLOW_OFF_IND, phyid);
+		service->phy_flow_on = false;
+		break;
+	case _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND:
+		if (phyid != service->dev_info.id)
+			return;
+		if (service->modem_flow_on) {
+			layr->up->ctrlcmd(layr->up,
+					   CAIF_CTRLCMD_FLOW_ON_IND,
+					   phyid);
+		}
+		service->phy_flow_on = true;
+		break;
+	case CAIF_CTRLCMD_FLOW_OFF_IND:
+		if (service->phy_flow_on) {
+			layr->up->ctrlcmd(layr->up,
+					  CAIF_CTRLCMD_FLOW_OFF_IND, phyid);
+		}
+		service->modem_flow_on = false;
+		break;
+	case CAIF_CTRLCMD_FLOW_ON_IND:
+		if (service->phy_flow_on) {
+			layr->up->ctrlcmd(layr->up,
+					  CAIF_CTRLCMD_FLOW_ON_IND, phyid);
+		}
+		service->modem_flow_on = true;
+		break;
+	case _CAIF_CTRLCMD_PHYIF_DOWN_IND:
+		/* In case interface is down, let's fake a remove shutdown */
+		layr->up->ctrlcmd(layr->up,
+				CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND, phyid);
+		break;
+	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
+		layr->up->ctrlcmd(layr->up, ctrl, phyid);
+		break;
+	default:
+		pr_warning("CAIF: %s(): "
+			   "Unexpected ctrl in cfsrvl (%d)\n", __func__, ctrl);
+		/* We have both modem and phy flow on, send flow on */
+		layr->up->ctrlcmd(layr->up, ctrl, phyid);
+		service->phy_flow_on = true;
+		break;
+	}
+}
+
+static int cfservl_modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl)
+{
+	struct cfsrvl *service = container_obj(layr);
+	caif_assert(layr != NULL);
+	caif_assert(layr->dn != NULL);
+	caif_assert(layr->dn->transmit != NULL);
+	switch (ctrl) {
+	case CAIF_MODEMCMD_FLOW_ON_REQ:
+		{
+			struct cfpkt *pkt;
+			struct caif_payload_info *info;
+			u8 flow_on = SRVL_FLOW_ON;
+			pkt = cfpkt_create(SRVL_CTRL_PKT_SIZE);
+			if (!pkt) {
+				pr_warning("CAIF: %s(): Out of memory\n",
+					__func__);
+				return -ENOMEM;
+			}
+
+			if (cfpkt_add_head(pkt, &flow_on, 1) < 0) {
+				pr_err("CAIF: %s(): Packet is erroneous!\n",
+					__func__);
+				cfpkt_destroy(pkt);
+				return -EPROTO;
+			}
+			info = cfpkt_info(pkt);
+			info->channel_id = service->layer.id;
+			info->hdr_len = 1;
+			info->dev_info = &service->dev_info;
+			return layr->dn->transmit(layr->dn, pkt);
+		}
+	case CAIF_MODEMCMD_FLOW_OFF_REQ:
+		{
+			struct cfpkt *pkt;
+			struct caif_payload_info *info;
+			u8 flow_off = SRVL_FLOW_OFF;
+			pkt = cfpkt_create(SRVL_CTRL_PKT_SIZE);
+			if (cfpkt_add_head(pkt, &flow_off, 1) < 0) {
+				pr_err("CAIF: %s(): Packet is erroneous!\n",
+					__func__);
+				cfpkt_destroy(pkt);
+				return -EPROTO;
+			}
+			info = cfpkt_info(pkt);
+			info->channel_id = service->layer.id;
+			info->hdr_len = 1;
+			info->dev_info = &service->dev_info;
+			return layr->dn->transmit(layr->dn, pkt);
+		}
+	default:
+	  break;
+	}
+	return -EINVAL;
+}
+
+void cfservl_destroy(struct cflayer *layer)
+{
+	kfree(layer);
+}
+
+void cfsrvl_init(struct cfsrvl *service,
+		 u8 channel_id,
+		 struct dev_info *dev_info)
+{
+	caif_assert(offsetof(struct cfsrvl, layer) == 0);
+	service->open = false;
+	service->modem_flow_on = true;
+	service->phy_flow_on = true;
+	service->layer.id = channel_id;
+	service->layer.ctrlcmd = cfservl_ctrlcmd;
+	service->layer.modemcmd = cfservl_modemcmd;
+	service->dev_info = *dev_info;
+}
+
+bool cfsrvl_ready(struct cfsrvl *service, int *err)
+{
+	if (service->open && service->modem_flow_on && service->phy_flow_on)
+		return true;
+	if (!service->open) {
+		*err = -ENOTCONN;
+		return false;
+	}
+	caif_assert(!(service->modem_flow_on && service->phy_flow_on));
+	*err = -EAGAIN;
+	return false;
+}
+u8 cfsrvl_getphyid(struct cflayer *layer)
+{
+	struct cfsrvl *servl = container_obj(layer);
+	return servl->dev_info.id;
+}
+
+bool cfsrvl_phyid_match(struct cflayer *layer, int phyid)
+{
+	struct cfsrvl *servl = container_obj(layer);
+	return servl->dev_info.id == phyid;
+}

net/caif/cfutill.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;
+}

net/caif/cfveil.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/stddef.h>
+#include <linux/slab.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfsrvl.h>
+#include <net/caif/cfpkt.h>
+
+#define VEI_PAYLOAD  0x00
+#define VEI_CMD_BIT  0x80
+#define VEI_FLOW_OFF 0x81
+#define VEI_FLOW_ON  0x80
+#define VEI_SET_PIN  0x82
+#define VEI_CTRL_PKT_SIZE 1
+#define container_obj(layr) container_of(layr, struct cfsrvl, layer)
+
+static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt);
+
+struct cflayer *cfvei_create(u8 channel_id, struct dev_info *dev_info)
+{
+	struct cfsrvl *vei = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+	if (!vei) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	caif_assert(offsetof(struct cfsrvl, layer) == 0);
+	memset(vei, 0, sizeof(struct cfsrvl));
+	cfsrvl_init(vei, channel_id, dev_info);
+	vei->layer.receive = cfvei_receive;
+	vei->layer.transmit = cfvei_transmit;
+	snprintf(vei->layer.name, CAIF_LAYER_NAME_SZ - 1, "vei%d", channel_id);
+	return &vei->layer;
+}
+
+static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u8 cmd;
+	int ret;
+	caif_assert(layr->up != NULL);
+	caif_assert(layr->receive != NULL);
+	caif_assert(layr->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 VEI_PAYLOAD:
+		ret = layr->up->receive(layr->up, pkt);
+		return ret;
+	case VEI_FLOW_OFF:
+		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
+		cfpkt_destroy(pkt);
+		return 0;
+	case VEI_FLOW_ON:
+		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
+		cfpkt_destroy(pkt);
+		return 0;
+	case VEI_SET_PIN:	/* SET RS232 PIN */
+		cfpkt_destroy(pkt);
+		return 0;
+	default:		/* SET RS232 PIN */
+		pr_warning("CAIF: %s():Unknown VEI control packet %d (0x%x)!\n",
+			   __func__, cmd, cmd);
+		cfpkt_destroy(pkt);
+		return -EPROTO;
+	}
+}
+
+static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u8 tmp = 0;
+	struct caif_payload_info *info;
+	int ret;
+	struct cfsrvl *service = container_obj(layr);
+	if (!cfsrvl_ready(service, &ret))
+		return ret;
+	caif_assert(layr->dn != NULL);
+	caif_assert(layr->dn->transmit != NULL);
+	if (!cfpkt_getlen(pkt) > CAIF_MAX_PAYLOAD_SIZE) {
+		pr_warning("CAIF: %s(): Packet too large - size=%d\n",
+			   __func__, cfpkt_getlen(pkt));
+		return -EOVERFLOW;
+	}
+
+	if (cfpkt_add_head(pkt, &tmp, 1) < 0) {
+		pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+		return -EPROTO;
+	}
+
+	/* Add info-> for MUX-layer to route the packet out. */
+	info = cfpkt_info(pkt);
+	info->channel_id = service->layer.id;
+	info->hdr_len = 1;
+	info->dev_info = &service->dev_info;
+	ret = layr->dn->transmit(layr->dn, pkt);
+	if (ret < 0)
+		cfpkt_extr_head(pkt, &tmp, 1);
+	return ret;
+}

net/caif/cfvidl.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)
+
+static int cfvidl_receive(struct cflayer *layr, struct cfpkt *pkt);
+static int cfvidl_transmit(struct cflayer *layr, struct cfpkt *pkt);
+
+struct cflayer *cfvidl_create(u8 channel_id, struct dev_info *dev_info)
+{
+	struct cfsrvl *vid = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+	if (!vid) {
+		pr_warning("CAIF: %s(): Out of memory\n", __func__);
+		return NULL;
+	}
+	caif_assert(offsetof(struct cfsrvl, layer) == 0);
+
+	memset(vid, 0, sizeof(struct cfsrvl));
+	cfsrvl_init(vid, channel_id, dev_info);
+	vid->layer.receive = cfvidl_receive;
+	vid->layer.transmit = cfvidl_transmit;
+	snprintf(vid->layer.name, CAIF_LAYER_NAME_SZ - 1, "vid1");
+	return &vid->layer;
+}
+
+static int cfvidl_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+	u32 videoheader;
+	if (cfpkt_extr_head(pkt, &videoheader, 4) < 0) {
+		pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
+		cfpkt_destroy(pkt);
+		return -EPROTO;
+	}
+	return layr->up->receive(layr->up, pkt);
+}
+
+static int cfvidl_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+	struct cfsrvl *service = container_obj(layr);
+	struct caif_payload_info *info;
+	u32 videoheader = 0;
+	int ret;
+	if (!cfsrvl_ready(service, &ret))
+		return ret;
+	cfpkt_add_head(pkt, &videoheader, 4);
+	/* Add info for MUX-layer to route the packet out */
+	info = cfpkt_info(pkt);
+	info->channel_id = service->layer.id;
+	info->dev_info = &service->dev_info;
+	ret = layr->dn->transmit(layr->dn, pkt);
+	if (ret < 0)
+		cfpkt_extr_head(pkt, &videoheader, 4);
+	return ret;
+}