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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/net/caif/caif_serial.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/net/caif/caif_serial.c')
-rw-r--r--drivers/net/caif/caif_serial.c453
1 files changed, 453 insertions, 0 deletions
diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c
new file mode 100644
index 000000000..688075859
--- /dev/null
+++ b/drivers/net/caif/caif_serial.c
@@ -0,0 +1,453 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author: Sjur Brendeland
+ */
+
+#include <linux/hardirq.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/tty.h>
+#include <linux/file.h>
+#include <linux/if_arp.h>
+#include <net/caif/caif_device.h>
+#include <net/caif/cfcnfg.h>
+#include <linux/err.h>
+#include <linux/debugfs.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sjur Brendeland");
+MODULE_DESCRIPTION("CAIF serial device TTY line discipline");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_LDISC(N_CAIF);
+
+#define SEND_QUEUE_LOW 10
+#define SEND_QUEUE_HIGH 100
+#define CAIF_SENDING 1 /* Bit 1 = 0x02*/
+#define CAIF_FLOW_OFF_SENT 4 /* Bit 4 = 0x10 */
+#define MAX_WRITE_CHUNK 4096
+#define ON 1
+#define OFF 0
+#define CAIF_MAX_MTU 4096
+
+static DEFINE_SPINLOCK(ser_lock);
+static LIST_HEAD(ser_list);
+static LIST_HEAD(ser_release_list);
+
+static bool ser_loop;
+module_param(ser_loop, bool, 0444);
+MODULE_PARM_DESC(ser_loop, "Run in simulated loopback mode.");
+
+static bool ser_use_stx = true;
+module_param(ser_use_stx, bool, 0444);
+MODULE_PARM_DESC(ser_use_stx, "STX enabled or not.");
+
+static bool ser_use_fcs = true;
+
+module_param(ser_use_fcs, bool, 0444);
+MODULE_PARM_DESC(ser_use_fcs, "FCS enabled or not.");
+
+static int ser_write_chunk = MAX_WRITE_CHUNK;
+module_param(ser_write_chunk, int, 0444);
+
+MODULE_PARM_DESC(ser_write_chunk, "Maximum size of data written to UART.");
+
+static struct dentry *debugfsdir;
+
+static int caif_net_open(struct net_device *dev);
+static int caif_net_close(struct net_device *dev);
+
+struct ser_device {
+ struct caif_dev_common common;
+ struct list_head node;
+ struct net_device *dev;
+ struct sk_buff_head head;
+ struct tty_struct *tty;
+ bool tx_started;
+ unsigned long state;
+#ifdef CONFIG_DEBUG_FS
+ struct dentry *debugfs_tty_dir;
+ struct debugfs_blob_wrapper tx_blob;
+ struct debugfs_blob_wrapper rx_blob;
+ u8 rx_data[128];
+ u8 tx_data[128];
+ u8 tty_status;
+
+#endif
+};
+
+static void caifdev_setup(struct net_device *dev);
+static void ldisc_tx_wakeup(struct tty_struct *tty);
+#ifdef CONFIG_DEBUG_FS
+static inline void update_tty_status(struct ser_device *ser)
+{
+ ser->tty_status =
+ ser->tty->flow.stopped << 5 |
+ ser->tty->flow.tco_stopped << 3 |
+ ser->tty->ctrl.packet << 2;
+}
+static inline void debugfs_init(struct ser_device *ser, struct tty_struct *tty)
+{
+ ser->debugfs_tty_dir = debugfs_create_dir(tty->name, debugfsdir);
+
+ debugfs_create_blob("last_tx_msg", 0400, ser->debugfs_tty_dir,
+ &ser->tx_blob);
+
+ debugfs_create_blob("last_rx_msg", 0400, ser->debugfs_tty_dir,
+ &ser->rx_blob);
+
+ debugfs_create_xul("ser_state", 0400, ser->debugfs_tty_dir,
+ &ser->state);
+
+ debugfs_create_x8("tty_status", 0400, ser->debugfs_tty_dir,
+ &ser->tty_status);
+
+ ser->tx_blob.data = ser->tx_data;
+ ser->tx_blob.size = 0;
+ ser->rx_blob.data = ser->rx_data;
+ ser->rx_blob.size = 0;
+}
+
+static inline void debugfs_deinit(struct ser_device *ser)
+{
+ debugfs_remove_recursive(ser->debugfs_tty_dir);
+}
+
+static inline void debugfs_rx(struct ser_device *ser, const u8 *data, int size)
+{
+ if (size > sizeof(ser->rx_data))
+ size = sizeof(ser->rx_data);
+ memcpy(ser->rx_data, data, size);
+ ser->rx_blob.data = ser->rx_data;
+ ser->rx_blob.size = size;
+}
+
+static inline void debugfs_tx(struct ser_device *ser, const u8 *data, int size)
+{
+ if (size > sizeof(ser->tx_data))
+ size = sizeof(ser->tx_data);
+ memcpy(ser->tx_data, data, size);
+ ser->tx_blob.data = ser->tx_data;
+ ser->tx_blob.size = size;
+}
+#else
+static inline void debugfs_init(struct ser_device *ser, struct tty_struct *tty)
+{
+}
+
+static inline void debugfs_deinit(struct ser_device *ser)
+{
+}
+
+static inline void update_tty_status(struct ser_device *ser)
+{
+}
+
+static inline void debugfs_rx(struct ser_device *ser, const u8 *data, int size)
+{
+}
+
+static inline void debugfs_tx(struct ser_device *ser, const u8 *data, int size)
+{
+}
+
+#endif
+
+static void ldisc_receive(struct tty_struct *tty, const u8 *data,
+ const char *flags, int count)
+{
+ struct sk_buff *skb = NULL;
+ struct ser_device *ser;
+ int ret;
+
+ ser = tty->disc_data;
+
+ /*
+ * NOTE: flags may contain information about break or overrun.
+ * This is not yet handled.
+ */
+
+
+ /*
+ * Workaround for garbage at start of transmission,
+ * only enable if STX handling is not enabled.
+ */
+ if (!ser->common.use_stx && !ser->tx_started) {
+ dev_info(&ser->dev->dev,
+ "Bytes received before initial transmission -"
+ "bytes discarded.\n");
+ return;
+ }
+
+ BUG_ON(ser->dev == NULL);
+
+ /* Get a suitable caif packet and copy in data. */
+ skb = netdev_alloc_skb(ser->dev, count+1);
+ if (skb == NULL)
+ return;
+ skb_put_data(skb, data, count);
+
+ skb->protocol = htons(ETH_P_CAIF);
+ skb_reset_mac_header(skb);
+ debugfs_rx(ser, data, count);
+ /* Push received packet up the stack. */
+ ret = netif_rx(skb);
+ if (!ret) {
+ ser->dev->stats.rx_packets++;
+ ser->dev->stats.rx_bytes += count;
+ } else
+ ++ser->dev->stats.rx_dropped;
+ update_tty_status(ser);
+}
+
+static int handle_tx(struct ser_device *ser)
+{
+ struct tty_struct *tty;
+ struct sk_buff *skb;
+ int tty_wr, len, room;
+
+ tty = ser->tty;
+ ser->tx_started = true;
+
+ /* Enter critical section */
+ if (test_and_set_bit(CAIF_SENDING, &ser->state))
+ return 0;
+
+ /* skb_peek is safe because handle_tx is called after skb_queue_tail */
+ while ((skb = skb_peek(&ser->head)) != NULL) {
+
+ /* Make sure you don't write too much */
+ len = skb->len;
+ room = tty_write_room(tty);
+ if (!room)
+ break;
+ if (room > ser_write_chunk)
+ room = ser_write_chunk;
+ if (len > room)
+ len = room;
+
+ /* Write to tty or loopback */
+ if (!ser_loop) {
+ tty_wr = tty->ops->write(tty, skb->data, len);
+ update_tty_status(ser);
+ } else {
+ tty_wr = len;
+ ldisc_receive(tty, skb->data, NULL, len);
+ }
+ ser->dev->stats.tx_packets++;
+ ser->dev->stats.tx_bytes += tty_wr;
+
+ /* Error on TTY ?! */
+ if (tty_wr < 0)
+ goto error;
+ /* Reduce buffer written, and discard if empty */
+ skb_pull(skb, tty_wr);
+ if (skb->len == 0) {
+ struct sk_buff *tmp = skb_dequeue(&ser->head);
+ WARN_ON(tmp != skb);
+ dev_consume_skb_any(skb);
+ }
+ }
+ /* Send flow off if queue is empty */
+ if (ser->head.qlen <= SEND_QUEUE_LOW &&
+ test_and_clear_bit(CAIF_FLOW_OFF_SENT, &ser->state) &&
+ ser->common.flowctrl != NULL)
+ ser->common.flowctrl(ser->dev, ON);
+ clear_bit(CAIF_SENDING, &ser->state);
+ return 0;
+error:
+ clear_bit(CAIF_SENDING, &ser->state);
+ return tty_wr;
+}
+
+static netdev_tx_t caif_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ser_device *ser;
+
+ ser = netdev_priv(dev);
+
+ /* Send flow off once, on high water mark */
+ if (ser->head.qlen > SEND_QUEUE_HIGH &&
+ !test_and_set_bit(CAIF_FLOW_OFF_SENT, &ser->state) &&
+ ser->common.flowctrl != NULL)
+
+ ser->common.flowctrl(ser->dev, OFF);
+
+ skb_queue_tail(&ser->head, skb);
+ return handle_tx(ser);
+}
+
+
+static void ldisc_tx_wakeup(struct tty_struct *tty)
+{
+ struct ser_device *ser;
+
+ ser = tty->disc_data;
+ BUG_ON(ser == NULL);
+ WARN_ON(ser->tty != tty);
+ handle_tx(ser);
+}
+
+
+static void ser_release(struct work_struct *work)
+{
+ struct list_head list;
+ struct ser_device *ser, *tmp;
+
+ spin_lock(&ser_lock);
+ list_replace_init(&ser_release_list, &list);
+ spin_unlock(&ser_lock);
+
+ if (!list_empty(&list)) {
+ rtnl_lock();
+ list_for_each_entry_safe(ser, tmp, &list, node) {
+ dev_close(ser->dev);
+ unregister_netdevice(ser->dev);
+ debugfs_deinit(ser);
+ }
+ rtnl_unlock();
+ }
+}
+
+static DECLARE_WORK(ser_release_work, ser_release);
+
+static int ldisc_open(struct tty_struct *tty)
+{
+ struct ser_device *ser;
+ struct net_device *dev;
+ char name[64];
+ int result;
+
+ /* No write no play */
+ if (tty->ops->write == NULL)
+ return -EOPNOTSUPP;
+ if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_TTY_CONFIG))
+ return -EPERM;
+
+ /* release devices to avoid name collision */
+ ser_release(NULL);
+
+ result = snprintf(name, sizeof(name), "cf%s", tty->name);
+ if (result >= IFNAMSIZ)
+ return -EINVAL;
+ dev = alloc_netdev(sizeof(*ser), name, NET_NAME_UNKNOWN,
+ caifdev_setup);
+ if (!dev)
+ return -ENOMEM;
+
+ ser = netdev_priv(dev);
+ ser->tty = tty_kref_get(tty);
+ ser->dev = dev;
+ debugfs_init(ser, tty);
+ tty->receive_room = N_TTY_BUF_SIZE;
+ tty->disc_data = ser;
+ set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+ rtnl_lock();
+ result = register_netdevice(dev);
+ if (result) {
+ tty_kref_put(tty);
+ rtnl_unlock();
+ free_netdev(dev);
+ return -ENODEV;
+ }
+
+ spin_lock(&ser_lock);
+ list_add(&ser->node, &ser_list);
+ spin_unlock(&ser_lock);
+ rtnl_unlock();
+ netif_stop_queue(dev);
+ update_tty_status(ser);
+ return 0;
+}
+
+static void ldisc_close(struct tty_struct *tty)
+{
+ struct ser_device *ser = tty->disc_data;
+
+ tty_kref_put(ser->tty);
+
+ spin_lock(&ser_lock);
+ list_move(&ser->node, &ser_release_list);
+ spin_unlock(&ser_lock);
+ schedule_work(&ser_release_work);
+}
+
+/* The line discipline structure. */
+static struct tty_ldisc_ops caif_ldisc = {
+ .owner = THIS_MODULE,
+ .num = N_CAIF,
+ .name = "n_caif",
+ .open = ldisc_open,
+ .close = ldisc_close,
+ .receive_buf = ldisc_receive,
+ .write_wakeup = ldisc_tx_wakeup
+};
+
+static const struct net_device_ops netdev_ops = {
+ .ndo_open = caif_net_open,
+ .ndo_stop = caif_net_close,
+ .ndo_start_xmit = caif_xmit
+};
+
+static void caifdev_setup(struct net_device *dev)
+{
+ struct ser_device *serdev = netdev_priv(dev);
+
+ dev->features = 0;
+ dev->netdev_ops = &netdev_ops;
+ dev->type = ARPHRD_CAIF;
+ dev->flags = IFF_POINTOPOINT | IFF_NOARP;
+ dev->mtu = CAIF_MAX_MTU;
+ dev->priv_flags |= IFF_NO_QUEUE;
+ dev->needs_free_netdev = true;
+ skb_queue_head_init(&serdev->head);
+ serdev->common.link_select = CAIF_LINK_LOW_LATENCY;
+ serdev->common.use_frag = true;
+ serdev->common.use_stx = ser_use_stx;
+ serdev->common.use_fcs = ser_use_fcs;
+ serdev->dev = dev;
+}
+
+
+static int caif_net_open(struct net_device *dev)
+{
+ netif_wake_queue(dev);
+ return 0;
+}
+
+static int caif_net_close(struct net_device *dev)
+{
+ netif_stop_queue(dev);
+ return 0;
+}
+
+static int __init caif_ser_init(void)
+{
+ int ret;
+
+ ret = tty_register_ldisc(&caif_ldisc);
+ if (ret < 0)
+ pr_err("cannot register CAIF ldisc=%d err=%d\n", N_CAIF, ret);
+
+ debugfsdir = debugfs_create_dir("caif_serial", NULL);
+ return ret;
+}
+
+static void __exit caif_ser_exit(void)
+{
+ spin_lock(&ser_lock);
+ list_splice(&ser_list, &ser_release_list);
+ spin_unlock(&ser_lock);
+ ser_release(NULL);
+ cancel_work_sync(&ser_release_work);
+ tty_unregister_ldisc(&caif_ldisc);
+ debugfs_remove_recursive(debugfsdir);
+}
+
+module_init(caif_ser_init);
+module_exit(caif_ser_exit);