diff options
Diffstat (limited to 'net/caif/cfmuxl.c')
-rw-r--r-- | net/caif/cfmuxl.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/net/caif/cfmuxl.c b/net/caif/cfmuxl.c new file mode 100644 index 000000000000..7372f27f1d32 --- /dev/null +++ b/net/caif/cfmuxl.c @@ -0,0 +1,251 @@ +/* + * 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); + cfsrvl_get(up); + 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); + if (up == NULL) + return NULL; + memset(muxl->up_cache, 0, sizeof(muxl->up_cache)); + list_del(&up->node); + cfsrvl_put(up); + 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; + } + cfsrvl_get(up); + ret = up->receive(up, pkt); + cfsrvl_put(up); + 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); + } +} |