diff options
Diffstat (limited to 'net/caif/caif_dev.c')
-rw-r--r-- | net/caif/caif_dev.c | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c new file mode 100644 index 00000000000..e84837e1bc8 --- /dev/null +++ b/net/caif/caif_dev.c @@ -0,0 +1,413 @@ +/* + * CAIF Interface registration. + * Copyright (C) ST-Ericsson AB 2010 + * Author: Sjur Brendeland/sjur.brandeland@stericsson.com + * License terms: GNU General Public License (GPL) version 2 + * + * Borrowed heavily from file: pn_dev.c. Thanks to + * Remi Denis-Courmont <remi.denis-courmont@nokia.com> + * and Sakari Ailus <sakari.ailus@nokia.com> + */ + +#include <linux/version.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/if_arp.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <linux/sched.h> +#include <linux/wait.h> +#include <net/netns/generic.h> +#include <net/net_namespace.h> +#include <net/pkt_sched.h> +#include <net/caif/caif_device.h> +#include <net/caif/caif_dev.h> +#include <net/caif/caif_layer.h> +#include <net/caif/cfpkt.h> +#include <net/caif/cfcnfg.h> + +MODULE_LICENSE("GPL"); +#define TIMEOUT (HZ*5) + +/* Used for local tracking of the CAIF net devices */ +struct caif_device_entry { + struct cflayer layer; + struct list_head list; + atomic_t in_use; + atomic_t state; + u16 phyid; + struct net_device *netdev; + wait_queue_head_t event; +}; + +struct caif_device_entry_list { + struct list_head list; + /* Protects simulanous deletes in list */ + spinlock_t lock; +}; + +struct caif_net { + struct caif_device_entry_list caifdevs; +}; + +static int caif_net_id; +static struct cfcnfg *cfg; + +static struct caif_device_entry_list *caif_device_list(struct net *net) +{ + struct caif_net *caifn; + BUG_ON(!net); + caifn = net_generic(net, caif_net_id); + BUG_ON(!caifn); + return &caifn->caifdevs; +} + +/* Allocate new CAIF device. */ +static struct caif_device_entry *caif_device_alloc(struct net_device *dev) +{ + struct caif_device_entry_list *caifdevs; + struct caif_device_entry *caifd; + caifdevs = caif_device_list(dev_net(dev)); + BUG_ON(!caifdevs); + caifd = kzalloc(sizeof(*caifd), GFP_ATOMIC); + if (!caifd) + return NULL; + caifd->netdev = dev; + list_add(&caifd->list, &caifdevs->list); + init_waitqueue_head(&caifd->event); + return caifd; +} + +static struct caif_device_entry *caif_get(struct net_device *dev) +{ + struct caif_device_entry_list *caifdevs = + caif_device_list(dev_net(dev)); + struct caif_device_entry *caifd; + BUG_ON(!caifdevs); + list_for_each_entry(caifd, &caifdevs->list, list) { + if (caifd->netdev == dev) + return caifd; + } + return NULL; +} + +static void caif_device_destroy(struct net_device *dev) +{ + struct caif_device_entry_list *caifdevs = + caif_device_list(dev_net(dev)); + struct caif_device_entry *caifd; + ASSERT_RTNL(); + if (dev->type != ARPHRD_CAIF) + return; + + spin_lock_bh(&caifdevs->lock); + caifd = caif_get(dev); + if (caifd == NULL) { + spin_unlock_bh(&caifdevs->lock); + return; + } + + list_del(&caifd->list); + spin_unlock_bh(&caifdevs->lock); + + kfree(caifd); + return; +} + +static int transmit(struct cflayer *layer, struct cfpkt *pkt) +{ + struct caif_device_entry *caifd = + container_of(layer, struct caif_device_entry, layer); + struct sk_buff *skb, *skb2; + int ret = -EINVAL; + skb = cfpkt_tonative(pkt); + skb->dev = caifd->netdev; + /* + * Don't allow SKB to be destroyed upon error, but signal resend + * notification to clients. We can't rely on the return value as + * congestion (NET_XMIT_CN) sometimes drops the packet, sometimes don't. + */ + if (netif_queue_stopped(caifd->netdev)) + return -EAGAIN; + skb2 = skb_get(skb); + + ret = dev_queue_xmit(skb2); + + if (!ret) + kfree_skb(skb); + else + return -EAGAIN; + + return 0; +} + +static int modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl) +{ + struct caif_device_entry *caifd; + struct caif_dev_common *caifdev; + caifd = container_of(layr, struct caif_device_entry, layer); + caifdev = netdev_priv(caifd->netdev); + if (ctrl == _CAIF_MODEMCMD_PHYIF_USEFULL) { + atomic_set(&caifd->in_use, 1); + wake_up_interruptible(&caifd->event); + + } else if (ctrl == _CAIF_MODEMCMD_PHYIF_USELESS) { + atomic_set(&caifd->in_use, 0); + wake_up_interruptible(&caifd->event); + } + return 0; +} + +/* + * Stuff received packets to associated sockets. + * On error, returns non-zero and releases the skb. + */ +static int receive(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pkttype, struct net_device *orig_dev) +{ + struct net *net; + struct cfpkt *pkt; + struct caif_device_entry *caifd; + net = dev_net(dev); + pkt = cfpkt_fromnative(CAIF_DIR_IN, skb); + caifd = caif_get(dev); + if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) + return NET_RX_DROP; + + if (caifd->layer.up->receive(caifd->layer.up, pkt)) + return NET_RX_DROP; + + return 0; +} + +static struct packet_type caif_packet_type __read_mostly = { + .type = cpu_to_be16(ETH_P_CAIF), + .func = receive, +}; + +static void dev_flowctrl(struct net_device *dev, int on) +{ + struct caif_device_entry *caifd = caif_get(dev); + if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) + return; + + caifd->layer.up->ctrlcmd(caifd->layer.up, + on ? + _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND : + _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND, + caifd->layer.id); +} + +/* notify Caif of device events */ +static int caif_device_notify(struct notifier_block *me, unsigned long what, + void *arg) +{ + struct net_device *dev = arg; + struct caif_device_entry *caifd = NULL; + struct caif_dev_common *caifdev; + enum cfcnfg_phy_preference pref; + int res = -EINVAL; + enum cfcnfg_phy_type phy_type; + + if (dev->type != ARPHRD_CAIF) + return 0; + + switch (what) { + case NETDEV_REGISTER: + pr_info("CAIF: %s():register %s\n", __func__, dev->name); + caifd = caif_device_alloc(dev); + if (caifd == NULL) + break; + caifdev = netdev_priv(dev); + caifdev->flowctrl = dev_flowctrl; + atomic_set(&caifd->state, what); + res = 0; + break; + + case NETDEV_UP: + pr_info("CAIF: %s(): up %s\n", __func__, dev->name); + caifd = caif_get(dev); + if (caifd == NULL) + break; + caifdev = netdev_priv(dev); + if (atomic_read(&caifd->state) == NETDEV_UP) { + pr_info("CAIF: %s():%s already up\n", + __func__, dev->name); + break; + } + atomic_set(&caifd->state, what); + caifd->layer.transmit = transmit; + caifd->layer.modemcmd = modemcmd; + + if (caifdev->use_frag) + phy_type = CFPHYTYPE_FRAG; + else + phy_type = CFPHYTYPE_CAIF; + + switch (caifdev->link_select) { + case CAIF_LINK_HIGH_BANDW: + pref = CFPHYPREF_LOW_LAT; + break; + case CAIF_LINK_LOW_LATENCY: + pref = CFPHYPREF_HIGH_BW; + break; + default: + pref = CFPHYPREF_HIGH_BW; + break; + } + + cfcnfg_add_phy_layer(get_caif_conf(), + phy_type, + dev, + &caifd->layer, + &caifd->phyid, + pref, + caifdev->use_fcs, + caifdev->use_stx); + strncpy(caifd->layer.name, dev->name, + sizeof(caifd->layer.name) - 1); + caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0; + break; + + case NETDEV_GOING_DOWN: + caifd = caif_get(dev); + if (caifd == NULL) + break; + pr_info("CAIF: %s():going down %s\n", __func__, dev->name); + + if (atomic_read(&caifd->state) == NETDEV_GOING_DOWN || + atomic_read(&caifd->state) == NETDEV_DOWN) + break; + + atomic_set(&caifd->state, what); + if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) + return -EINVAL; + caifd->layer.up->ctrlcmd(caifd->layer.up, + _CAIF_CTRLCMD_PHYIF_DOWN_IND, + caifd->layer.id); + res = wait_event_interruptible_timeout(caifd->event, + atomic_read(&caifd->in_use) == 0, + TIMEOUT); + break; + + case NETDEV_DOWN: + caifd = caif_get(dev); + if (caifd == NULL) + break; + pr_info("CAIF: %s(): down %s\n", __func__, dev->name); + if (atomic_read(&caifd->in_use)) + pr_warning("CAIF: %s(): " + "Unregistering an active CAIF device: %s\n", + __func__, dev->name); + cfcnfg_del_phy_layer(get_caif_conf(), &caifd->layer); + atomic_set(&caifd->state, what); + break; + + case NETDEV_UNREGISTER: + caifd = caif_get(dev); + pr_info("CAIF: %s(): unregister %s\n", __func__, dev->name); + atomic_set(&caifd->state, what); + caif_device_destroy(dev); + break; + } + return 0; +} + +static struct notifier_block caif_device_notifier = { + .notifier_call = caif_device_notify, + .priority = 0, +}; + + +struct cfcnfg *get_caif_conf(void) +{ + return cfg; +} +EXPORT_SYMBOL(get_caif_conf); + +int caif_connect_client(struct caif_connect_request *conn_req, + struct cflayer *client_layer) +{ + struct cfctrl_link_param param; + if (connect_req_to_link_param(get_caif_conf(), conn_req, ¶m) == 0) + /* Hook up the adaptation layer. */ + return cfcnfg_add_adaptation_layer(get_caif_conf(), + ¶m, client_layer); + + return -EINVAL; + + caif_assert(0); +} +EXPORT_SYMBOL(caif_connect_client); + +int caif_disconnect_client(struct cflayer *adap_layer) +{ + return cfcnfg_del_adapt_layer(get_caif_conf(), adap_layer); +} +EXPORT_SYMBOL(caif_disconnect_client); + +/* Per-namespace Caif devices handling */ +static int caif_init_net(struct net *net) +{ + struct caif_net *caifn = net_generic(net, caif_net_id); + INIT_LIST_HEAD(&caifn->caifdevs.list); + spin_lock_init(&caifn->caifdevs.lock); + return 0; +} + +static void caif_exit_net(struct net *net) +{ + struct net_device *dev; + int res; + rtnl_lock(); + for_each_netdev(net, dev) { + if (dev->type != ARPHRD_CAIF) + continue; + res = dev_close(dev); + caif_device_destroy(dev); + } + rtnl_unlock(); +} + +static struct pernet_operations caif_net_ops = { + .init = caif_init_net, + .exit = caif_exit_net, + .id = &caif_net_id, + .size = sizeof(struct caif_net), +}; + +/* Initialize Caif devices list */ +static int __init caif_device_init(void) +{ + int result; + cfg = cfcnfg_create(); + if (!cfg) { + pr_warning("CAIF: %s(): can't create cfcnfg.\n", __func__); + goto err_cfcnfg_create_failed; + } + result = register_pernet_device(&caif_net_ops); + + if (result) { + kfree(cfg); + cfg = NULL; + return result; + } + dev_add_pack(&caif_packet_type); + register_netdevice_notifier(&caif_device_notifier); + + return result; +err_cfcnfg_create_failed: + return -ENODEV; +} + +static void __exit caif_device_exit(void) +{ + dev_remove_pack(&caif_packet_type); + unregister_pernet_device(&caif_net_ops); + unregister_netdevice_notifier(&caif_device_notifier); + cfcnfg_remove(cfg); +} + +module_init(caif_device_init); +module_exit(caif_device_exit); |