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>
diff --git a/net/caif/cfmuxl.c b/net/caif/cfmuxl.c
new file mode 100644
index 0000000..6fb9f9e
--- /dev/null
+++ b/net/caif/cfmuxl.c
@@ -0,0 +1,246 @@
+/*
+ * 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);
+ }
+}