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>

1 files changed, 185 insertions, 0 deletions

diff --git a/net/caif/cfsrvl.c b/net/caif/cfsrvl.c
new file mode 100644
index 0000000..d470c51
--- /dev/null
+++ b/net/caif/cfsrvl.c
@@ -0,0 +1,185 @@
+/*
+ * 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;
+}