v4.19.13 snapshot.
diff --git a/net/caif/cfdgml.c b/net/caif/cfdgml.c
new file mode 100644
index 0000000..3bdddb3
--- /dev/null
+++ b/net/caif/cfdgml.c
@@ -0,0 +1,114 @@
+/*
+ * 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/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_MTU 1500
+
+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 = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+ if (!dgm)
+ return NULL;
+ caif_assert(offsetof(struct cfsrvl, layer) == 0);
+ cfsrvl_init(dgm, channel_id, dev_info, true);
+ 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("Packet is erroneous!\n");
+ cfpkt_destroy(pkt);
+ return -EPROTO;
+ }
+
+ if ((cmd & DGM_CMD_BIT) == 0) {
+ if (cfpkt_extr_head(pkt, &dgmhdr, 3) < 0) {
+ pr_err("Packet is erroneous!\n");
+ 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("Unknown datagram control %d (0x%x)\n", cmd, cmd);
+ return -EPROTO;
+ }
+}
+
+static int cfdgml_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+ u8 packet_type;
+ u32 zero = 0;
+ struct caif_payload_info *info;
+ struct cfsrvl *service = container_obj(layr);
+ int ret;
+
+ if (!cfsrvl_ready(service, &ret)) {
+ cfpkt_destroy(pkt);
+ return ret;
+ }
+
+ /* STE Modem cannot handle more than 1500 bytes datagrams */
+ if (cfpkt_getlen(pkt) > DGM_MTU) {
+ cfpkt_destroy(pkt);
+ return -EMSGSIZE;
+ }
+
+ cfpkt_add_head(pkt, &zero, 3);
+ packet_type = 0x08; /* B9 set - UNCLASSIFIED */
+ cfpkt_add_head(pkt, &packet_type, 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 = 4;
+ info->dev_info = &service->dev_info;
+ return layr->dn->transmit(layr->dn, pkt);
+}