File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/caif/cfveil.c b/net/caif/cfveil.c
new file mode 100644
index 0000000..2622245
--- /dev/null
+++ b/net/caif/cfveil.c
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author:	Sjur Brendeland
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
+
+#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 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 = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+	if (!vei)
+		return NULL;
+	caif_assert(offsetof(struct cfsrvl, layer) == 0);
+	cfsrvl_init(vei, channel_id, dev_info, true);
+	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("Packet is erroneous!\n");
+		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_warn("Unknown VEI control packet %d (0x%x)!\n", 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))
+		goto err;
+	caif_assert(layr->dn != NULL);
+	caif_assert(layr->dn->transmit != NULL);
+
+	if (cfpkt_add_head(pkt, &tmp, 1) < 0) {
+		pr_err("Packet is erroneous!\n");
+		ret = -EPROTO;
+		goto err;
+	}
+
+	/* 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;
+	return layr->dn->transmit(layr->dn, pkt);
+err:
+	cfpkt_destroy(pkt);
+	return ret;
+}