--- /dev/null
+/*
+ * FireWire Serial driver
+ *
+ * Copyright (C) 2012 Peter Hurley <peter@hurleysoftware.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/rculist.h>
+#include <linux/workqueue.h>
+#include <linux/ratelimit.h>
+#include <linux/bug.h>
+#include <linux/uaccess.h>
+
+#include "fwserial.h"
+
+#define be32_to_u64(hi, lo) ((u64)be32_to_cpu(hi) << 32 | be32_to_cpu(lo))
+
+#define LINUX_VENDOR_ID 0xd00d1eU /* same id used in card root directory */
+#define FWSERIAL_VERSION 0x00e81cU /* must be unique within LINUX_VENDOR_ID */
+
+/* configurable options */
+static int num_ttys = 4; /* # of std ttys to create per fw_card */
+ /* - doubles as loopback port index */
+static bool auto_connect = true; /* try to VIRT_CABLE to every peer */
+static bool create_loop_dev = true; /* create a loopback device for each card */
+
+module_param_named(ttys, num_ttys, int, S_IRUGO | S_IWUSR);
+module_param_named(auto, auto_connect, bool, S_IRUGO | S_IWUSR);
+module_param_named(loop, create_loop_dev, bool, S_IRUGO | S_IWUSR);
+
+/*
+ * Threshold below which the tty is woken for writing
+ * - should be equal to WAKEUP_CHARS in drivers/tty/n_tty.c because
+ * even if the writer is woken, n_tty_poll() won't set POLLOUT until
+ * our fifo is below this level
+ */
+#define WAKEUP_CHARS 256
+
+/**
+ * fwserial_list: list of every fw_serial created for each fw_card
+ * See discussion in fwserial_probe.
+ */
+static LIST_HEAD(fwserial_list);
+static DEFINE_MUTEX(fwserial_list_mutex);
+
+/**
+ * port_table: array of tty ports allocated to each fw_card
+ *
+ * tty ports are allocated during probe when an fw_serial is first
+ * created for a given fw_card. Ports are allocated in a contiguous block,
+ * each block consisting of 'num_ports' ports.
+ */
+static struct fwtty_port *port_table[MAX_TOTAL_PORTS];
+static DEFINE_MUTEX(port_table_lock);
+static bool port_table_corrupt;
+#define FWTTY_INVALID_INDEX MAX_TOTAL_PORTS
+
+#define loop_idx(port) (((port)->index) / num_ports)
+#define table_idx(loop) ((loop) * num_ports + num_ttys)
+
+/* total # of tty ports created per fw_card */
+static int num_ports;
+
+/* slab used as pool for struct fwtty_transactions */
+static struct kmem_cache *fwtty_txn_cache;
+
+struct tty_driver *fwtty_driver;
+static struct tty_driver *fwloop_driver;
+
+static struct dentry *fwserial_debugfs;
+
+struct fwtty_transaction;
+typedef void (*fwtty_transaction_cb)(struct fw_card *card, int rcode,
+ void *data, size_t length,
+ struct fwtty_transaction *txn);
+
+struct fwtty_transaction {
+ struct fw_transaction fw_txn;
+ fwtty_transaction_cb callback;
+ struct fwtty_port *port;
+ union {
+ struct dma_pending dma_pended;
+ };
+};
+
+#define to_device(a, b) (a->b)
+#define fwtty_err(p, fmt, ...) \
+ dev_err(to_device(p, device), fmt, ##__VA_ARGS__)
+#define fwtty_info(p, fmt, ...) \
+ dev_info(to_device(p, device), fmt, ##__VA_ARGS__)
+#define fwtty_notice(p, fmt, ...) \
+ dev_notice(to_device(p, device), fmt, ##__VA_ARGS__)
+#define fwtty_dbg(p, fmt, ...) \
+ dev_dbg(to_device(p, device), "%s: " fmt, __func__, ##__VA_ARGS__)
+#define fwtty_err_ratelimited(p, fmt, ...) \
+ dev_err_ratelimited(to_device(p, device), fmt, ##__VA_ARGS__)
+
+#ifdef DEBUG
+static inline void debug_short_write(struct fwtty_port *port, int c, int n)
+{
+ int avail;
+
+ if (n < c) {
+ spin_lock_bh(&port->lock);
+ avail = dma_fifo_avail(&port->tx_fifo);
+ spin_unlock_bh(&port->lock);
+ fwtty_dbg(port, "short write: avail:%d req:%d wrote:%d\n",
+ avail, c, n);
+ }
+}
+#else
+#define debug_short_write(port, c, n)
+#endif
+
+static struct fwtty_peer *__fwserial_peer_by_node_id(struct fw_card *card,
+ int generation, int id);
+
+#ifdef FWTTY_PROFILING
+
+static void fwtty_profile_fifo(struct fwtty_port *port, unsigned *stat)
+{
+ spin_lock_bh(&port->lock);
+ fwtty_profile_data(stat, dma_fifo_avail(&port->tx_fifo));
+ spin_unlock_bh(&port->lock);
+}
+
+static void fwtty_dump_profile(struct seq_file *m, struct stats *stats)
+{
+ /* for each stat, print sum of 0 to 2^k, then individually */
+ int k = 4;
+ unsigned sum;
+ int j;
+ char t[10];
+
+ snprintf(t, 10, "< %d", 1 << k);
+ seq_printf(m, "\n%14s %6s", " ", t);
+ for (j = k + 1; j < DISTRIBUTION_MAX_INDEX; ++j)
+ seq_printf(m, "%6d", 1 << j);
+
+ ++k;
+ for (j = 0, sum = 0; j <= k; ++j)
+ sum += stats->reads[j];
+ seq_printf(m, "\n%14s: %6d", "reads", sum);
+ for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j)
+ seq_printf(m, "%6d", stats->reads[j]);
+
+ for (j = 0, sum = 0; j <= k; ++j)
+ sum += stats->writes[j];
+ seq_printf(m, "\n%14s: %6d", "writes", sum);
+ for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j)
+ seq_printf(m, "%6d", stats->writes[j]);
+
+ for (j = 0, sum = 0; j <= k; ++j)
+ sum += stats->txns[j];
+ seq_printf(m, "\n%14s: %6d", "txns", sum);
+ for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j)
+ seq_printf(m, "%6d", stats->txns[j]);
+
+ for (j = 0, sum = 0; j <= k; ++j)
+ sum += stats->unthrottle[j];
+ seq_printf(m, "\n%14s: %6d", "avail @ unthr", sum);
+ for (j = k + 1; j <= DISTRIBUTION_MAX_INDEX; ++j)
+ seq_printf(m, "%6d", stats->unthrottle[j]);
+}
+
+#else
+#define fwtty_profile_fifo(port, stat)
+#define fwtty_dump_profile(m, stats)
+#endif
+
+/*
+ * Returns the max receive packet size for the given node
+ * Devices which are OHCI v1.0/ v1.1/ v1.2-draft or RFC 2734 compliant
+ * are required by specification to support max_rec of 8 (512 bytes) or more.
+ */
+static inline int device_max_receive(struct fw_device *fw_device)
+{
+ /* see IEEE 1394-2008 table 8-8 */
+ return min(2 << fw_device->max_rec, 4096);
+}
+
+static void fwtty_log_tx_error(struct fwtty_port *port, int rcode)
+{
+ switch (rcode) {
+ case RCODE_SEND_ERROR:
+ fwtty_err_ratelimited(port, "card busy\n");
+ break;
+ case RCODE_ADDRESS_ERROR:
+ fwtty_err_ratelimited(port, "bad unit addr or write length\n");
+ break;
+ case RCODE_DATA_ERROR:
+ fwtty_err_ratelimited(port, "failed rx\n");
+ break;
+ case RCODE_NO_ACK:
+ fwtty_err_ratelimited(port, "missing ack\n");
+ break;
+ case RCODE_BUSY:
+ fwtty_err_ratelimited(port, "remote busy\n");
+ break;
+ default:
+ fwtty_err_ratelimited(port, "failed tx: %d\n", rcode);
+ }
+}
+
+static void fwtty_txn_constructor(void *this)
+{
+ struct fwtty_transaction *txn = this;
+
+ init_timer(&txn->fw_txn.split_timeout_timer);
+}
+
+static void fwtty_common_callback(struct fw_card *card, int rcode,
+ void *payload, size_t len, void *cb_data)
+{
+ struct fwtty_transaction *txn = cb_data;
+ struct fwtty_port *port = txn->port;
+
+ if (port && rcode != RCODE_COMPLETE)
+ fwtty_log_tx_error(port, rcode);
+ if (txn->callback)
+ txn->callback(card, rcode, payload, len, txn);
+ kmem_cache_free(fwtty_txn_cache, txn);
+}
+
+static int fwtty_send_data_async(struct fwtty_peer *peer, int tcode,
+ unsigned long long addr, void *payload,
+ size_t len, fwtty_transaction_cb callback,
+ struct fwtty_port *port)
+{
+ struct fwtty_transaction *txn;
+ int generation;
+
+ txn = kmem_cache_alloc(fwtty_txn_cache, GFP_ATOMIC);
+ if (!txn)
+ return -ENOMEM;
+
+ txn->callback = callback;
+ txn->port = port;
+
+ generation = peer->generation;
+ smp_rmb();
+ fw_send_request(peer->serial->card, &txn->fw_txn, tcode,
+ peer->node_id, generation, peer->speed, addr, payload,
+ len, fwtty_common_callback, txn);
+ return 0;
+}
+
+static void fwtty_send_txn_async(struct fwtty_peer *peer,
+ struct fwtty_transaction *txn, int tcode,
+ unsigned long long addr, void *payload,
+ size_t len, fwtty_transaction_cb callback,
+ struct fwtty_port *port)
+{
+ int generation;
+
+ txn->callback = callback;
+ txn->port = port;
+
+ generation = peer->generation;
+ smp_rmb();
+ fw_send_request(peer->serial->card, &txn->fw_txn, tcode,
+ peer->node_id, generation, peer->speed, addr, payload,
+ len, fwtty_common_callback, txn);
+}
+
+static void __fwtty_restart_tx(struct fwtty_port *port)
+{
+ int len, avail;
+
+ len = dma_fifo_out_level(&port->tx_fifo);
+ if (len)
+ schedule_delayed_work(&port->drain, 0);
+ avail = dma_fifo_avail(&port->tx_fifo);
+
+ fwtty_dbg(port, "fifo len: %d avail: %d\n", len, avail);
+}
+
+static void fwtty_restart_tx(struct fwtty_port *port)
+{
+ spin_lock_bh(&port->lock);
+ __fwtty_restart_tx(port);
+ spin_unlock_bh(&port->lock);
+}
+
+/**
+ * fwtty_update_port_status - decodes & dispatches line status changes
+ *
+ * Note: in loopback, the port->lock is being held. Only use functions that
+ * don't attempt to reclaim the port->lock.
+ */
+static void fwtty_update_port_status(struct fwtty_port *port, unsigned status)
+{
+ unsigned delta;
+ struct tty_struct *tty;
+
+ /* simulated LSR/MSR status from remote */
+ status &= ~MCTRL_MASK;
+ delta = (port->mstatus ^ status) & ~MCTRL_MASK;
+ delta &= ~(status & TIOCM_RNG);
+ port->mstatus = status;
+
+ if (delta & TIOCM_RNG)
+ ++port->icount.rng;
+ if (delta & TIOCM_DSR)
+ ++port->icount.dsr;
+ if (delta & TIOCM_CAR)
+ ++port->icount.dcd;
+ if (delta & TIOCM_CTS)
+ ++port->icount.cts;
+
+ fwtty_dbg(port, "status: %x delta: %x\n", status, delta);
+
+ if (delta & TIOCM_CAR) {
+ tty = tty_port_tty_get(&port->port);
+ if (tty && !C_CLOCAL(tty)) {
+ if (status & TIOCM_CAR)
+ wake_up_interruptible(&port->port.open_wait);
+ else
+ schedule_work(&port->hangup);
+ }
+ tty_kref_put(tty);
+ }
+
+ if (delta & TIOCM_CTS) {
+ tty = tty_port_tty_get(&port->port);
+ if (tty && C_CRTSCTS(tty)) {
+ if (tty->hw_stopped) {
+ if (status & TIOCM_CTS) {
+ tty->hw_stopped = 0;
+ if (port->loopback)
+ __fwtty_restart_tx(port);
+ else
+ fwtty_restart_tx(port);
+ }
+ } else {
+ if (~status & TIOCM_CTS)
+ tty->hw_stopped = 1;
+ }
+ }
+ tty_kref_put(tty);
+
+ } else if (delta & OOB_TX_THROTTLE) {
+ tty = tty_port_tty_get(&port->port);
+ if (tty) {
+ if (tty->hw_stopped) {
+ if (~status & OOB_TX_THROTTLE) {
+ tty->hw_stopped = 0;
+ if (port->loopback)
+ __fwtty_restart_tx(port);
+ else
+ fwtty_restart_tx(port);
+ }
+ } else {
+ if (status & OOB_TX_THROTTLE)
+ tty->hw_stopped = 1;
+ }
+ }
+ tty_kref_put(tty);
+ }
+
+ if (delta & (UART_LSR_BI << 24)) {
+ if (status & (UART_LSR_BI << 24)) {
+ port->break_last = jiffies;
+ schedule_delayed_work(&port->emit_breaks, 0);
+ } else {
+ /* run emit_breaks one last time (if pending) */
+ mod_delayed_work(system_wq, &port->emit_breaks, 0);
+ }
+ }
+
+ if (delta & (TIOCM_DSR | TIOCM_CAR | TIOCM_CTS | TIOCM_RNG))
+ wake_up_interruptible(&port->port.delta_msr_wait);
+}
+
+/**
+ * __fwtty_port_line_status - generate 'line status' for indicated port
+ *
+ * This function returns a remote 'MSR' state based on the local 'MCR' state,
+ * as if a null modem cable was attached. The actual status is a mangling
+ * of TIOCM_* bits suitable for sending to a peer's status_addr.
+ *
+ * Note: caller must be holding port lock
+ */
+static unsigned __fwtty_port_line_status(struct fwtty_port *port)
+{
+ unsigned status = 0;
+
+ /* TODO: add module param to tie RNG to DTR as well */
+
+ if (port->mctrl & TIOCM_DTR)
+ status |= TIOCM_DSR | TIOCM_CAR;
+ if (port->mctrl & TIOCM_RTS)
+ status |= TIOCM_CTS;
+ if (port->mctrl & OOB_RX_THROTTLE)
+ status |= OOB_TX_THROTTLE;
+ /* emulate BRK as add'l line status */
+ if (port->break_ctl)
+ status |= UART_LSR_BI << 24;
+
+ return status;
+}
+
+/**
+ * __fwtty_write_port_status - send the port line status to peer
+ *
+ * Note: caller must be holding the port lock.
+ */
+static int __fwtty_write_port_status(struct fwtty_port *port)
+{
+ struct fwtty_peer *peer;
+ int err = -ENOENT;
+ unsigned status = __fwtty_port_line_status(port);
+
+ rcu_read_lock();
+ peer = rcu_dereference(port->peer);
+ if (peer) {
+ err = fwtty_send_data_async(peer, TCODE_WRITE_QUADLET_REQUEST,
+ peer->status_addr, &status,
+ sizeof(status), NULL, port);
+ }
+ rcu_read_unlock();
+
+ return err;
+}
+
+/**
+ * fwtty_write_port_status - same as above but locked by port lock
+ */
+static int fwtty_write_port_status(struct fwtty_port *port)
+{
+ int err;
+
+ spin_lock_bh(&port->lock);
+ err = __fwtty_write_port_status(port);
+ spin_unlock_bh(&port->lock);
+ return err;
+}
+
+static void fwtty_throttle_port(struct fwtty_port *port)
+{
+ struct tty_struct *tty;
+ unsigned old;
+
+ tty = tty_port_tty_get(&port->port);
+ if (!tty)
+ return;
+
+ spin_lock_bh(&port->lock);
+
+ old = port->mctrl;
+ port->mctrl |= OOB_RX_THROTTLE;
+ if (C_CRTSCTS(tty))
+ port->mctrl &= ~TIOCM_RTS;
+ if (~old & OOB_RX_THROTTLE)
+ __fwtty_write_port_status(port);
+
+ spin_unlock_bh(&port->lock);
+
+ tty_kref_put(tty);
+}
+
+/**
+ * fwtty_do_hangup - wait for ldisc to deliver all pending rx; only then hangup
+ *
+ * When the remote has finished tx, and all in-flight rx has been received and
+ * and pushed to the flip buffer, the remote may close its device. This will
+ * drop DTR on the remote which will drop carrier here. Typically, the tty is
+ * hung up when carrier is dropped or lost.
+ *
+ * However, there is a race between the hang up and the line discipline
+ * delivering its data to the reader. A hangup will cause the ldisc to flush
+ * (ie., clear) the read buffer and flip buffer. Because of firewire's
+ * relatively high throughput, the ldisc frequently lags well behind the driver,
+ * resulting in lost data (which has already been received and written to
+ * the flip buffer) when the remote closes its end.
+ *
+ * Unfortunately, since the flip buffer offers no direct method for determining
+ * if it holds data, ensuring the ldisc has delivered all data is problematic.
+ */
+
+/* FIXME: drop this workaround when __tty_hangup waits for ldisc completion */
+static void fwtty_do_hangup(struct work_struct *work)
+{
+ struct fwtty_port *port = to_port(work, hangup);
+ struct tty_struct *tty;
+
+ schedule_timeout_uninterruptible(msecs_to_jiffies(50));
+
+ tty = tty_port_tty_get(&port->port);
+ if (tty)
+ tty_vhangup(tty);
+ tty_kref_put(tty);
+}
+
+static void fwtty_emit_breaks(struct work_struct *work)
+{
+ struct fwtty_port *port = to_port(to_delayed_work(work), emit_breaks);
+ static const char buf[16];
+ unsigned long now = jiffies;
+ unsigned long elapsed = now - port->break_last;
+ int n, t, c, brk = 0;
+
+ /* generate breaks at the line rate (but at least 1) */
+ n = (elapsed * port->cps) / HZ + 1;
+ port->break_last = now;
+
+ fwtty_dbg(port, "sending %d brks\n", n);
+
+ while (n) {
+ t = min(n, 16);
+ c = tty_insert_flip_string_fixed_flag(&port->port, buf,
+ TTY_BREAK, t);
+ n -= c;
+ brk += c;
+ if (c < t)
+ break;
+ }
+ tty_flip_buffer_push(&port->port);
+
+ if (port->mstatus & (UART_LSR_BI << 24))
+ schedule_delayed_work(&port->emit_breaks, FREQ_BREAKS);
+ port->icount.brk += brk;
+}
+
+static int fwtty_rx(struct fwtty_port *port, unsigned char *data, size_t len)
+{
+ int c, n = len;
+ unsigned lsr;
+ int err = 0;
+
+ fwtty_dbg(port, "%d\n", n);
+ fwtty_profile_data(port->stats.reads, n);
+
+ if (port->write_only) {
+ n = 0;
+ goto out;
+ }
+
+ /* disregard break status; breaks are generated by emit_breaks work */
+ lsr = (port->mstatus >> 24) & ~UART_LSR_BI;
+
+ if (port->overrun)
+ lsr |= UART_LSR_OE;
+
+ if (lsr & UART_LSR_OE)
+ ++port->icount.overrun;
+
+ lsr &= port->status_mask;
+ if (lsr & ~port->ignore_mask & UART_LSR_OE) {
+ if (!tty_insert_flip_char(&port->port, 0, TTY_OVERRUN)) {
+ err = -EIO;
+ goto out;
+ }
+ }
+ port->overrun = false;
+
+ if (lsr & port->ignore_mask & ~UART_LSR_OE) {
+ /* TODO: don't drop SAK and Magic SysRq here */
+ n = 0;
+ goto out;
+ }
+
+ c = tty_insert_flip_string_fixed_flag(&port->port, data, TTY_NORMAL, n);
+ if (c > 0)
+ tty_flip_buffer_push(&port->port);
+ n -= c;
+
+ if (n) {
+ port->overrun = true;
+ err = -EIO;
+ fwtty_err_ratelimited(port, "flip buffer overrun\n");
+
+ } else {
+ /* throttle the sender if remaining flip buffer space has
+ * reached high watermark to avoid losing data which may be
+ * in-flight. Since the AR request context is 32k, that much
+ * data may have _already_ been acked.
+ */
+ if (tty_buffer_space_avail(&port->port) < HIGH_WATERMARK)
+ fwtty_throttle_port(port);
+ }
+
+out:
+ port->icount.rx += len;
+ port->stats.lost += n;
+ return err;
+}
+
+/**
+ * fwtty_port_handler - bus address handler for port reads/writes
+ * @parameters: fw_address_callback_t as specified by firewire core interface
+ *
+ * This handler is responsible for handling inbound read/write dma from remotes.
+ */
+static void fwtty_port_handler(struct fw_card *card,
+ struct fw_request *request,
+ int tcode, int destination, int source,
+ int generation,
+ unsigned long long addr,
+ void *data, size_t len,
+ void *callback_data)
+{
+ struct fwtty_port *port = callback_data;
+ struct fwtty_peer *peer;
+ int err;
+ int rcode;
+
+ /* Only accept rx from the peer virtual-cabled to this port */
+ rcu_read_lock();
+ peer = __fwserial_peer_by_node_id(card, generation, source);
+ rcu_read_unlock();
+ if (!peer || peer != rcu_access_pointer(port->peer)) {
+ rcode = RCODE_ADDRESS_ERROR;
+ fwtty_err_ratelimited(port, "ignoring unauthenticated data\n");
+ goto respond;
+ }
+
+ switch (tcode) {
+ case TCODE_WRITE_QUADLET_REQUEST:
+ if (addr != port->rx_handler.offset || len != 4) {
+ rcode = RCODE_ADDRESS_ERROR;
+ } else {
+ fwtty_update_port_status(port, *(unsigned *)data);
+ rcode = RCODE_COMPLETE;
+ }
+ break;
+
+ case TCODE_WRITE_BLOCK_REQUEST:
+ if (addr != port->rx_handler.offset + 4 ||
+ len > port->rx_handler.length - 4) {
+ rcode = RCODE_ADDRESS_ERROR;
+ } else {
+ err = fwtty_rx(port, data, len);
+ switch (err) {
+ case 0:
+ rcode = RCODE_COMPLETE;
+ break;
+ case -EIO:
+ rcode = RCODE_DATA_ERROR;
+ break;
+ default:
+ rcode = RCODE_CONFLICT_ERROR;
+ break;
+ }
+ }
+ break;
+
+ default:
+ rcode = RCODE_TYPE_ERROR;
+ }
+
+respond:
+ fw_send_response(card, request, rcode);
+}
+
+/**
+ * fwtty_tx_complete - callback for tx dma
+ * @data: ignored, has no meaning for write txns
+ * @length: ignored, has no meaning for write txns
+ *
+ * The writer must be woken here if the fifo has been emptied because it
+ * may have slept if chars_in_buffer was != 0
+ */
+static void fwtty_tx_complete(struct fw_card *card, int rcode,
+ void *data, size_t length,
+ struct fwtty_transaction *txn)
+{
+ struct fwtty_port *port = txn->port;
+ int len;
+
+ fwtty_dbg(port, "rcode: %d\n", rcode);
+
+ switch (rcode) {
+ case RCODE_COMPLETE:
+ spin_lock_bh(&port->lock);
+ dma_fifo_out_complete(&port->tx_fifo, &txn->dma_pended);
+ len = dma_fifo_level(&port->tx_fifo);
+ spin_unlock_bh(&port->lock);
+
+ port->icount.tx += txn->dma_pended.len;
+ break;
+
+ default:
+ /* TODO: implement retries */
+ spin_lock_bh(&port->lock);
+ dma_fifo_out_complete(&port->tx_fifo, &txn->dma_pended);
+ len = dma_fifo_level(&port->tx_fifo);
+ spin_unlock_bh(&port->lock);
+
+ port->stats.dropped += txn->dma_pended.len;
+ }
+
+ if (len < WAKEUP_CHARS)
+ tty_port_tty_wakeup(&port->port);
+}
+
+static int fwtty_tx(struct fwtty_port *port, bool drain)
+{
+ struct fwtty_peer *peer;
+ struct fwtty_transaction *txn;
+ struct tty_struct *tty;
+ int n, len;
+
+ tty = tty_port_tty_get(&port->port);
+ if (!tty)
+ return -ENOENT;
+
+ rcu_read_lock();
+ peer = rcu_dereference(port->peer);
+ if (!peer) {
+ n = -EIO;
+ goto out;
+ }
+
+ if (test_and_set_bit(IN_TX, &port->flags)) {
+ n = -EALREADY;
+ goto out;
+ }
+
+ /* try to write as many dma transactions out as possible */
+ n = -EAGAIN;
+ while (!tty->stopped && !tty->hw_stopped &&
+ !test_bit(STOP_TX, &port->flags)) {
+ txn = kmem_cache_alloc(fwtty_txn_cache, GFP_ATOMIC);
+ if (!txn) {
+ n = -ENOMEM;
+ break;
+ }
+
+ spin_lock_bh(&port->lock);
+ n = dma_fifo_out_pend(&port->tx_fifo, &txn->dma_pended);
+ spin_unlock_bh(&port->lock);
+
+ fwtty_dbg(port, "out: %u rem: %d\n", txn->dma_pended.len, n);
+
+ if (n < 0) {
+ kmem_cache_free(fwtty_txn_cache, txn);
+ if (n == -EAGAIN) {
+ ++port->stats.tx_stall;
+ } else if (n == -ENODATA) {
+ fwtty_profile_data(port->stats.txns, 0);
+ } else {
+ ++port->stats.fifo_errs;
+ fwtty_err_ratelimited(port, "fifo err: %d\n",
+ n);
+ }
+ break;
+ }
+
+ fwtty_profile_data(port->stats.txns, txn->dma_pended.len);
+
+ fwtty_send_txn_async(peer, txn, TCODE_WRITE_BLOCK_REQUEST,
+ peer->fifo_addr, txn->dma_pended.data,
+ txn->dma_pended.len, fwtty_tx_complete,
+ port);
+ ++port->stats.sent;
+
+ /*
+ * Stop tx if the 'last view' of the fifo is empty or if
+ * this is the writer and there's not enough data to bother
+ */
+ if (n == 0 || (!drain && n < WRITER_MINIMUM))
+ break;
+ }
+
+ if (n >= 0 || n == -EAGAIN || n == -ENOMEM || n == -ENODATA) {
+ spin_lock_bh(&port->lock);
+ len = dma_fifo_out_level(&port->tx_fifo);
+ if (len) {
+ unsigned long delay = (n == -ENOMEM) ? HZ : 1;
+
+ schedule_delayed_work(&port->drain, delay);
+ }
+ len = dma_fifo_level(&port->tx_fifo);
+ spin_unlock_bh(&port->lock);
+
+ /* wakeup the writer */
+ if (drain && len < WAKEUP_CHARS)
+ tty_wakeup(tty);
+ }
+
+ clear_bit(IN_TX, &port->flags);
+ wake_up_interruptible(&port->wait_tx);
+
+out:
+ rcu_read_unlock();
+ tty_kref_put(tty);
+ return n;
+}
+
+static void fwtty_drain_tx(struct work_struct *work)
+{
+ struct fwtty_port *port = to_port(to_delayed_work(work), drain);
+
+ fwtty_tx(port, true);
+}
+
+static void fwtty_write_xchar(struct fwtty_port *port, char ch)
+{
+ struct fwtty_peer *peer;
+
+ ++port->stats.xchars;
+
+ fwtty_dbg(port, "%02x\n", ch);
+
+ rcu_read_lock();
+ peer = rcu_dereference(port->peer);
+ if (peer) {
+ fwtty_send_data_async(peer, TCODE_WRITE_BLOCK_REQUEST,
+ peer->fifo_addr, &ch, sizeof(ch),
+ NULL, port);
+ }
+ rcu_read_unlock();
+}
+
+struct fwtty_port *fwtty_port_get(unsigned index)
+{
+ struct fwtty_port *port;
+
+ if (index >= MAX_TOTAL_PORTS)
+ return NULL;
+
+ mutex_lock(&port_table_lock);
+ port = port_table[index];
+ if (port)
+ kref_get(&port->serial->kref);
+ mutex_unlock(&port_table_lock);
+ return port;
+}
+EXPORT_SYMBOL(fwtty_port_get);
+
+static int fwtty_ports_add(struct fw_serial *serial)
+{
+ int err = -EBUSY;
+ int i, j;
+
+ if (port_table_corrupt)
+ return err;
+
+ mutex_lock(&port_table_lock);
+ for (i = 0; i + num_ports <= MAX_TOTAL_PORTS; i += num_ports) {
+ if (!port_table[i]) {
+ for (j = 0; j < num_ports; ++i, ++j) {
+ serial->ports[j]->index = i;
+ port_table[i] = serial->ports[j];
+ }
+ err = 0;
+ break;
+ }
+ }
+ mutex_unlock(&port_table_lock);
+ return err;
+}
+
+static void fwserial_destroy(struct kref *kref)
+{
+ struct fw_serial *serial = to_serial(kref, kref);
+ struct fwtty_port **ports = serial->ports;
+ int j, i = ports[0]->index;
+
+ synchronize_rcu();
+
+ mutex_lock(&port_table_lock);
+ for (j = 0; j < num_ports; ++i, ++j) {
+ port_table_corrupt |= port_table[i] != ports[j];
+ WARN_ONCE(port_table_corrupt, "port_table[%d]: %p != ports[%d]: %p",
+ i, port_table[i], j, ports[j]);
+
+ port_table[i] = NULL;
+ }
+ mutex_unlock(&port_table_lock);
+
+ for (j = 0; j < num_ports; ++j) {
+ fw_core_remove_address_handler(&ports[j]->rx_handler);
+ tty_port_destroy(&ports[j]->port);
+ kfree(ports[j]);
+ }
+ kfree(serial);
+}
+
+void fwtty_port_put(struct fwtty_port *port)
+{
+ kref_put(&port->serial->kref, fwserial_destroy);
+}
+EXPORT_SYMBOL(fwtty_port_put);
+
+static void fwtty_port_dtr_rts(struct tty_port *tty_port, int on)
+{
+ struct fwtty_port *port = to_port(tty_port, port);
+
+ fwtty_dbg(port, "on/off: %d\n", on);
+
+ spin_lock_bh(&port->lock);
+ /* Don't change carrier state if this is a console */
+ if (!port->port.console) {
+ if (on)
+ port->mctrl |= TIOCM_DTR | TIOCM_RTS;
+ else
+ port->mctrl &= ~(TIOCM_DTR | TIOCM_RTS);
+ }
+
+ __fwtty_write_port_status(port);
+ spin_unlock_bh(&port->lock);
+}
+
+/**
+ * fwtty_port_carrier_raised: required tty_port operation
+ *
+ * This port operation is polled after a tty has been opened and is waiting for
+ * carrier detect -- see drivers/tty/tty_port:tty_port_block_til_ready().
+ */
+static int fwtty_port_carrier_raised(struct tty_port *tty_port)
+{
+ struct fwtty_port *port = to_port(tty_port, port);
+ int rc;
+
+ rc = (port->mstatus & TIOCM_CAR);
+
+ fwtty_dbg(port, "%d\n", rc);
+
+ return rc;
+}
+
+static unsigned set_termios(struct fwtty_port *port, struct tty_struct *tty)
+{
+ unsigned baud, frame;
+
+ baud = tty_termios_baud_rate(&tty->termios);
+ tty_termios_encode_baud_rate(&tty->termios, baud, baud);
+
+ /* compute bit count of 2 frames */
+ frame = 12 + ((C_CSTOPB(tty)) ? 4 : 2) + ((C_PARENB(tty)) ? 2 : 0);
+
+ switch (C_CSIZE(tty)) {
+ case CS5:
+ frame -= (C_CSTOPB(tty)) ? 1 : 0;
+ break;
+ case CS6:
+ frame += 2;
+ break;
+ case CS7:
+ frame += 4;
+ break;
+ case CS8:
+ frame += 6;
+ break;
+ }
+
+ port->cps = (baud << 1) / frame;
+
+ port->status_mask = UART_LSR_OE;
+ if (_I_FLAG(tty, BRKINT | PARMRK))
+ port->status_mask |= UART_LSR_BI;
+
+ port->ignore_mask = 0;
+ if (I_IGNBRK(tty)) {
+ port->ignore_mask |= UART_LSR_BI;
+ if (I_IGNPAR(tty))
+ port->ignore_mask |= UART_LSR_OE;
+ }
+
+ port->write_only = !C_CREAD(tty);
+
+ /* turn off echo and newline xlat if loopback */
+ if (port->loopback) {
+ tty->termios.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHOKE |
+ ECHONL | ECHOPRT | ECHOCTL);
+ tty->termios.c_oflag &= ~ONLCR;
+ }
+
+ return baud;
+}
+
+static int fwtty_port_activate(struct tty_port *tty_port,
+ struct tty_struct *tty)
+{
+ struct fwtty_port *port = to_port(tty_port, port);
+ unsigned baud;
+ int err;
+
+ set_bit(TTY_IO_ERROR, &tty->flags);
+
+ err = dma_fifo_alloc(&port->tx_fifo, FWTTY_PORT_TXFIFO_LEN,
+ cache_line_size(),
+ port->max_payload,
+ FWTTY_PORT_MAX_PEND_DMA,
+ GFP_KERNEL);
+ if (err)
+ return err;
+
+ spin_lock_bh(&port->lock);
+
+ baud = set_termios(port, tty);
+
+ /* if console, don't change carrier state */
+ if (!port->port.console) {
+ port->mctrl = 0;
+ if (baud != 0)
+ port->mctrl = TIOCM_DTR | TIOCM_RTS;
+ }
+
+ if (C_CRTSCTS(tty) && ~port->mstatus & TIOCM_CTS)
+ tty->hw_stopped = 1;
+
+ __fwtty_write_port_status(port);
+ spin_unlock_bh(&port->lock);
+
+ clear_bit(TTY_IO_ERROR, &tty->flags);
+
+ return 0;
+}
+
+/**
+ * fwtty_port_shutdown
+ *
+ * Note: the tty port core ensures this is not the console and
+ * manages TTY_IO_ERROR properly
+ */
+static void fwtty_port_shutdown(struct tty_port *tty_port)
+{
+ struct fwtty_port *port = to_port(tty_port, port);
+
+ /* TODO: cancel outstanding transactions */
+
+ cancel_delayed_work_sync(&port->emit_breaks);
+ cancel_delayed_work_sync(&port->drain);
+
+ spin_lock_bh(&port->lock);
+ port->flags = 0;
+ port->break_ctl = 0;
+ port->overrun = 0;
+ __fwtty_write_port_status(port);
+ dma_fifo_free(&port->tx_fifo);
+ spin_unlock_bh(&port->lock);
+}
+
+static int fwtty_open(struct tty_struct *tty, struct file *fp)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ return tty_port_open(&port->port, tty, fp);
+}
+
+static void fwtty_close(struct tty_struct *tty, struct file *fp)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ tty_port_close(&port->port, tty, fp);
+}
+
+static void fwtty_hangup(struct tty_struct *tty)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ tty_port_hangup(&port->port);
+}
+
+static void fwtty_cleanup(struct tty_struct *tty)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ tty->driver_data = NULL;
+ fwtty_port_put(port);
+}
+
+static int fwtty_install(struct tty_driver *driver, struct tty_struct *tty)
+{
+ struct fwtty_port *port = fwtty_port_get(tty->index);
+ int err;
+
+ err = tty_standard_install(driver, tty);
+ if (!err)
+ tty->driver_data = port;
+ else
+ fwtty_port_put(port);
+ return err;
+}
+
+static int fwloop_install(struct tty_driver *driver, struct tty_struct *tty)
+{
+ struct fwtty_port *port = fwtty_port_get(table_idx(tty->index));
+ int err;
+
+ err = tty_standard_install(driver, tty);
+ if (!err)
+ tty->driver_data = port;
+ else
+ fwtty_port_put(port);
+ return err;
+}
+
+static int fwtty_write(struct tty_struct *tty, const unsigned char *buf, int c)
+{
+ struct fwtty_port *port = tty->driver_data;
+ int n, len;
+
+ fwtty_dbg(port, "%d\n", c);
+ fwtty_profile_data(port->stats.writes, c);
+
+ spin_lock_bh(&port->lock);
+ n = dma_fifo_in(&port->tx_fifo, buf, c);
+ len = dma_fifo_out_level(&port->tx_fifo);
+ if (len < DRAIN_THRESHOLD)
+ schedule_delayed_work(&port->drain, 1);
+ spin_unlock_bh(&port->lock);
+
+ if (len >= DRAIN_THRESHOLD)
+ fwtty_tx(port, false);
+
+ debug_short_write(port, c, n);
+
+ return (n < 0) ? 0 : n;
+}
+
+static int fwtty_write_room(struct tty_struct *tty)
+{
+ struct fwtty_port *port = tty->driver_data;
+ int n;
+
+ spin_lock_bh(&port->lock);
+ n = dma_fifo_avail(&port->tx_fifo);
+ spin_unlock_bh(&port->lock);
+
+ fwtty_dbg(port, "%d\n", n);
+
+ return n;
+}
+
+static int fwtty_chars_in_buffer(struct tty_struct *tty)
+{
+ struct fwtty_port *port = tty->driver_data;
+ int n;
+
+ spin_lock_bh(&port->lock);
+ n = dma_fifo_level(&port->tx_fifo);
+ spin_unlock_bh(&port->lock);
+
+ fwtty_dbg(port, "%d\n", n);
+
+ return n;
+}
+
+static void fwtty_send_xchar(struct tty_struct *tty, char ch)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ fwtty_dbg(port, "%02x\n", ch);
+
+ fwtty_write_xchar(port, ch);
+}
+
+static void fwtty_throttle(struct tty_struct *tty)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ /*
+ * Ignore throttling (but not unthrottling).
+ * It only makes sense to throttle when data will no longer be
+ * accepted by the tty flip buffer. For example, it is
+ * possible for received data to overflow the tty buffer long
+ * before the line discipline ever has a chance to throttle the driver.
+ * Additionally, the driver may have already completed the I/O
+ * but the tty buffer is still emptying, so the line discipline is
+ * throttling and unthrottling nothing.
+ */
+
+ ++port->stats.throttled;
+}
+
+static void fwtty_unthrottle(struct tty_struct *tty)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ fwtty_dbg(port, "CRTSCTS: %d\n", C_CRTSCTS(tty) != 0);
+
+ fwtty_profile_fifo(port, port->stats.unthrottle);
+
+ spin_lock_bh(&port->lock);
+ port->mctrl &= ~OOB_RX_THROTTLE;
+ if (C_CRTSCTS(tty))
+ port->mctrl |= TIOCM_RTS;
+ __fwtty_write_port_status(port);
+ spin_unlock_bh(&port->lock);
+}
+
+static int check_msr_delta(struct fwtty_port *port, unsigned long mask,
+ struct async_icount *prev)
+{
+ struct async_icount now;
+ int delta;
+
+ now = port->icount;
+
+ delta = ((mask & TIOCM_RNG && prev->rng != now.rng) ||
+ (mask & TIOCM_DSR && prev->dsr != now.dsr) ||
+ (mask & TIOCM_CAR && prev->dcd != now.dcd) ||
+ (mask & TIOCM_CTS && prev->cts != now.cts));
+
+ *prev = now;
+
+ return delta;
+}
+
+static int wait_msr_change(struct fwtty_port *port, unsigned long mask)
+{
+ struct async_icount prev;
+
+ prev = port->icount;
+
+ return wait_event_interruptible(port->port.delta_msr_wait,
+ check_msr_delta(port, mask, &prev));
+}
+
+static int get_serial_info(struct fwtty_port *port,
+ struct serial_struct __user *info)
+{
+ struct serial_struct tmp;
+
+ memset(&tmp, 0, sizeof(tmp));
+
+ tmp.type = PORT_UNKNOWN;
+ tmp.line = port->port.tty->index;
+ tmp.flags = port->port.flags;
+ tmp.xmit_fifo_size = FWTTY_PORT_TXFIFO_LEN;
+ tmp.baud_base = 400000000;
+ tmp.close_delay = port->port.close_delay;
+
+ return (copy_to_user(info, &tmp, sizeof(*info))) ? -EFAULT : 0;
+}
+
+static int set_serial_info(struct fwtty_port *port,
+ struct serial_struct __user *info)
+{
+ struct serial_struct tmp;
+
+ if (copy_from_user(&tmp, info, sizeof(tmp)))
+ return -EFAULT;
+
+ if (tmp.irq != 0 || tmp.port != 0 || tmp.custom_divisor != 0 ||
+ tmp.baud_base != 400000000)
+ return -EPERM;
+
+ if (!capable(CAP_SYS_ADMIN)) {
+ if (((tmp.flags & ~ASYNC_USR_MASK) !=
+ (port->port.flags & ~ASYNC_USR_MASK)))
+ return -EPERM;
+ } else {
+ port->port.close_delay = tmp.close_delay * HZ / 100;
+ }
+
+ return 0;
+}
+
+static int fwtty_ioctl(struct tty_struct *tty, unsigned cmd,
+ unsigned long arg)
+{
+ struct fwtty_port *port = tty->driver_data;
+ int err;
+
+ switch (cmd) {
+ case TIOCGSERIAL:
+ mutex_lock(&port->port.mutex);
+ err = get_serial_info(port, (void __user *)arg);
+ mutex_unlock(&port->port.mutex);
+ break;
+
+ case TIOCSSERIAL:
+ mutex_lock(&port->port.mutex);
+ err = set_serial_info(port, (void __user *)arg);
+ mutex_unlock(&port->port.mutex);
+ break;
+
+ case TIOCMIWAIT:
+ err = wait_msr_change(port, arg);
+ break;
+
+ default:
+ err = -ENOIOCTLCMD;
+ }
+
+ return err;
+}
+
+static void fwtty_set_termios(struct tty_struct *tty, struct ktermios *old)
+{
+ struct fwtty_port *port = tty->driver_data;
+ unsigned baud;
+
+ spin_lock_bh(&port->lock);
+ baud = set_termios(port, tty);
+
+ if ((baud == 0) && (old->c_cflag & CBAUD)) {
+ port->mctrl &= ~(TIOCM_DTR | TIOCM_RTS);
+ } else if ((baud != 0) && !(old->c_cflag & CBAUD)) {
+ if (C_CRTSCTS(tty) || !test_bit(TTY_THROTTLED, &tty->flags))
+ port->mctrl |= TIOCM_DTR | TIOCM_RTS;
+ else
+ port->mctrl |= TIOCM_DTR;
+ }
+ __fwtty_write_port_status(port);
+ spin_unlock_bh(&port->lock);
+
+ if (old->c_cflag & CRTSCTS) {
+ if (!C_CRTSCTS(tty)) {
+ tty->hw_stopped = 0;
+ fwtty_restart_tx(port);
+ }
+ } else if (C_CRTSCTS(tty) && ~port->mstatus & TIOCM_CTS) {
+ tty->hw_stopped = 1;
+ }
+}
+
+/**
+ * fwtty_break_ctl - start/stop sending breaks
+ *
+ * Signals the remote to start or stop generating simulated breaks.
+ * First, stop dequeueing from the fifo and wait for writer/drain to leave tx
+ * before signalling the break line status. This guarantees any pending rx will
+ * be queued to the line discipline before break is simulated on the remote.
+ * Conversely, turning off break_ctl requires signalling the line status change,
+ * then enabling tx.
+ */
+static int fwtty_break_ctl(struct tty_struct *tty, int state)
+{
+ struct fwtty_port *port = tty->driver_data;
+ long ret;
+
+ fwtty_dbg(port, "%d\n", state);
+
+ if (state == -1) {
+ set_bit(STOP_TX, &port->flags);
+ ret = wait_event_interruptible_timeout(port->wait_tx,
+ !test_bit(IN_TX, &port->flags),
+ 10);
+ if (ret == 0 || ret == -ERESTARTSYS) {
+ clear_bit(STOP_TX, &port->flags);
+ fwtty_restart_tx(port);
+ return -EINTR;
+ }
+ }
+
+ spin_lock_bh(&port->lock);
+ port->break_ctl = (state == -1);
+ __fwtty_write_port_status(port);
+ spin_unlock_bh(&port->lock);
+
+ if (state == 0) {
+ spin_lock_bh(&port->lock);
+ dma_fifo_reset(&port->tx_fifo);
+ clear_bit(STOP_TX, &port->flags);
+ spin_unlock_bh(&port->lock);
+ }
+ return 0;
+}
+
+static int fwtty_tiocmget(struct tty_struct *tty)
+{
+ struct fwtty_port *port = tty->driver_data;
+ unsigned tiocm;
+
+ spin_lock_bh(&port->lock);
+ tiocm = (port->mctrl & MCTRL_MASK) | (port->mstatus & ~MCTRL_MASK);
+ spin_unlock_bh(&port->lock);
+
+ fwtty_dbg(port, "%x\n", tiocm);
+
+ return tiocm;
+}
+
+static int fwtty_tiocmset(struct tty_struct *tty, unsigned set, unsigned clear)
+{
+ struct fwtty_port *port = tty->driver_data;
+
+ fwtty_dbg(port, "set: %x clear: %x\n", set, clear);
+
+ /* TODO: simulate loopback if TIOCM_LOOP set */
+
+ spin_lock_bh(&port->lock);
+ port->mctrl &= ~(clear & MCTRL_MASK & 0xffff);
+ port->mctrl |= set & MCTRL_MASK & 0xffff;
+ __fwtty_write_port_status(port);
+ spin_unlock_bh(&port->lock);
+ return 0;
+}
+
+static int fwtty_get_icount(struct tty_struct *tty,
+ struct serial_icounter_struct *icount)
+{
+ struct fwtty_port *port = tty->driver_data;
+ struct stats stats;
+
+ memcpy(&stats, &port->stats, sizeof(stats));
+ if (port->port.console)
+ (*port->fwcon_ops->stats)(&stats, port->con_data);
+
+ icount->cts = port->icount.cts;
+ icount->dsr = port->icount.dsr;
+ icount->rng = port->icount.rng;
+ icount->dcd = port->icount.dcd;
+ icount->rx = port->icount.rx;
+ icount->tx = port->icount.tx + stats.xchars;
+ icount->frame = port->icount.frame;
+ icount->overrun = port->icount.overrun;
+ icount->parity = port->icount.parity;
+ icount->brk = port->icount.brk;
+ icount->buf_overrun = port->icount.overrun;
+ return 0;
+}
+
+static void fwtty_proc_show_port(struct seq_file *m, struct fwtty_port *port)
+{
+ struct stats stats;
+
+ memcpy(&stats, &port->stats, sizeof(stats));
+ if (port->port.console)
+ (*port->fwcon_ops->stats)(&stats, port->con_data);
+
+ seq_printf(m, " addr:%012llx tx:%d rx:%d", port->rx_handler.offset,
+ port->icount.tx + stats.xchars, port->icount.rx);
+ seq_printf(m, " cts:%d dsr:%d rng:%d dcd:%d", port->icount.cts,
+ port->icount.dsr, port->icount.rng, port->icount.dcd);
+ seq_printf(m, " fe:%d oe:%d pe:%d brk:%d", port->icount.frame,
+ port->icount.overrun, port->icount.parity, port->icount.brk);
+}
+
+static void fwtty_debugfs_show_port(struct seq_file *m, struct fwtty_port *port)
+{
+ struct stats stats;
+
+ memcpy(&stats, &port->stats, sizeof(stats));
+ if (port->port.console)
+ (*port->fwcon_ops->stats)(&stats, port->con_data);
+
+ seq_printf(m, " dr:%d st:%d err:%d lost:%d", stats.dropped,
+ stats.tx_stall, stats.fifo_errs, stats.lost);
+ seq_printf(m, " pkts:%d thr:%d", stats.sent, stats.throttled);
+
+ if (port->port.console) {
+ seq_puts(m, "\n ");
+ (*port->fwcon_ops->proc_show)(m, port->con_data);
+ }
+
+ fwtty_dump_profile(m, &port->stats);
+}
+
+static void fwtty_debugfs_show_peer(struct seq_file *m, struct fwtty_peer *peer)
+{
+ int generation = peer->generation;
+
+ smp_rmb();
+ seq_printf(m, " %s:", dev_name(&peer->unit->device));
+ seq_printf(m, " node:%04x gen:%d", peer->node_id, generation);
+ seq_printf(m, " sp:%d max:%d guid:%016llx", peer->speed,
+ peer->max_payload, (unsigned long long) peer->guid);
+ seq_printf(m, " mgmt:%012llx", (unsigned long long) peer->mgmt_addr);
+ seq_printf(m, " addr:%012llx", (unsigned long long) peer->status_addr);
+ seq_putc(m, '\n');
+}
+
+static int fwtty_proc_show(struct seq_file *m, void *v)
+{
+ struct fwtty_port *port;
+ int i;
+
+ seq_puts(m, "fwserinfo: 1.0 driver: 1.0\n");
+ for (i = 0; i < MAX_TOTAL_PORTS && (port = fwtty_port_get(i)); ++i) {
+ seq_printf(m, "%2d:", i);
+ if (capable(CAP_SYS_ADMIN))
+ fwtty_proc_show_port(m, port);
+ fwtty_port_put(port);
+ seq_puts(m, "\n");
+ }
+ return 0;
+}
+
+static int fwtty_debugfs_stats_show(struct seq_file *m, void *v)
+{
+ struct fw_serial *serial = m->private;
+ struct fwtty_port *port;
+ int i;
+
+ for (i = 0; i < num_ports; ++i) {
+ port = fwtty_port_get(serial->ports[i]->index);
+ if (port) {
+ seq_printf(m, "%2d:", port->index);
+ fwtty_proc_show_port(m, port);
+ fwtty_debugfs_show_port(m, port);
+ fwtty_port_put(port);
+ seq_puts(m, "\n");
+ }
+ }
+ return 0;
+}
+
+static int fwtty_debugfs_peers_show(struct seq_file *m, void *v)
+{
+ struct fw_serial *serial = m->private;
+ struct fwtty_peer *peer;
+
+ rcu_read_lock();
+ seq_printf(m, "card: %s guid: %016llx\n",
+ dev_name(serial->card->device),
+ (unsigned long long) serial->card->guid);
+ list_for_each_entry_rcu(peer, &serial->peer_list, list)
+ fwtty_debugfs_show_peer(m, peer);
+ rcu_read_unlock();
+ return 0;
+}
+
+static int fwtty_proc_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, fwtty_proc_show, NULL);
+}
+
+static int fwtty_stats_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, fwtty_debugfs_stats_show, inode->i_private);
+}
+
+static int fwtty_peers_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, fwtty_debugfs_peers_show, inode->i_private);
+}
+
+static const struct file_operations fwtty_stats_fops = {
+ .owner = THIS_MODULE,
+ .open = fwtty_stats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static const struct file_operations fwtty_peers_fops = {
+ .owner = THIS_MODULE,
+ .open = fwtty_peers_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static const struct file_operations fwtty_proc_fops = {
+ .owner = THIS_MODULE,
+ .open = fwtty_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static const struct tty_port_operations fwtty_port_ops = {
+ .dtr_rts = fwtty_port_dtr_rts,
+ .carrier_raised = fwtty_port_carrier_raised,
+ .shutdown = fwtty_port_shutdown,
+ .activate = fwtty_port_activate,
+};
+
+static const struct tty_operations fwtty_ops = {
+ .open = fwtty_open,
+ .close = fwtty_close,
+ .hangup = fwtty_hangup,
+ .cleanup = fwtty_cleanup,
+ .install = fwtty_install,
+ .write = fwtty_write,
+ .write_room = fwtty_write_room,
+ .chars_in_buffer = fwtty_chars_in_buffer,
+ .send_xchar = fwtty_send_xchar,
+ .throttle = fwtty_throttle,
+ .unthrottle = fwtty_unthrottle,
+ .ioctl = fwtty_ioctl,
+ .set_termios = fwtty_set_termios,
+ .break_ctl = fwtty_break_ctl,
+ .tiocmget = fwtty_tiocmget,
+ .tiocmset = fwtty_tiocmset,
+ .get_icount = fwtty_get_icount,
+ .proc_fops = &fwtty_proc_fops,
+};
+
+static const struct tty_operations fwloop_ops = {
+ .open = fwtty_open,
+ .close = fwtty_close,
+ .hangup = fwtty_hangup,
+ .cleanup = fwtty_cleanup,
+ .install = fwloop_install,
+ .write = fwtty_write,
+ .write_room = fwtty_write_room,
+ .chars_in_buffer = fwtty_chars_in_buffer,
+ .send_xchar = fwtty_send_xchar,
+ .throttle = fwtty_throttle,
+ .unthrottle = fwtty_unthrottle,
+ .ioctl = fwtty_ioctl,
+ .set_termios = fwtty_set_termios,
+ .break_ctl = fwtty_break_ctl,
+ .tiocmget = fwtty_tiocmget,
+ .tiocmset = fwtty_tiocmset,
+ .get_icount = fwtty_get_icount,
+};
+
+static inline int mgmt_pkt_expected_len(__be16 code)
+{
+ static const struct fwserial_mgmt_pkt pkt;
+
+ switch (be16_to_cpu(code)) {
+ case FWSC_VIRT_CABLE_PLUG:
+ return sizeof(pkt.hdr) + sizeof(pkt.plug_req);
+
+ case FWSC_VIRT_CABLE_PLUG_RSP: /* | FWSC_RSP_OK */
+ return sizeof(pkt.hdr) + sizeof(pkt.plug_rsp);
+
+ case FWSC_VIRT_CABLE_UNPLUG:
+ case FWSC_VIRT_CABLE_UNPLUG_RSP:
+ case FWSC_VIRT_CABLE_PLUG_RSP | FWSC_RSP_NACK:
+ case FWSC_VIRT_CABLE_UNPLUG_RSP | FWSC_RSP_NACK:
+ return sizeof(pkt.hdr);
+
+ default:
+ return -1;
+ }
+}
+
+static inline void fill_plug_params(struct virt_plug_params *params,
+ struct fwtty_port *port)
+{
+ u64 status_addr = port->rx_handler.offset;
+ u64 fifo_addr = port->rx_handler.offset + 4;
+ size_t fifo_len = port->rx_handler.length - 4;
+
+ params->status_hi = cpu_to_be32(status_addr >> 32);
+ params->status_lo = cpu_to_be32(status_addr);
+ params->fifo_hi = cpu_to_be32(fifo_addr >> 32);
+ params->fifo_lo = cpu_to_be32(fifo_addr);
+ params->fifo_len = cpu_to_be32(fifo_len);
+}
+
+static inline void fill_plug_req(struct fwserial_mgmt_pkt *pkt,
+ struct fwtty_port *port)
+{
+ pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_PLUG);
+ pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code));
+ fill_plug_params(&pkt->plug_req, port);
+}
+
+static inline void fill_plug_rsp_ok(struct fwserial_mgmt_pkt *pkt,
+ struct fwtty_port *port)
+{
+ pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_PLUG_RSP);
+ pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code));
+ fill_plug_params(&pkt->plug_rsp, port);
+}
+
+static inline void fill_plug_rsp_nack(struct fwserial_mgmt_pkt *pkt)
+{
+ pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_PLUG_RSP | FWSC_RSP_NACK);
+ pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code));
+}
+
+static inline void fill_unplug_req(struct fwserial_mgmt_pkt *pkt)
+{
+ pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_UNPLUG);
+ pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code));
+}
+
+static inline void fill_unplug_rsp_nack(struct fwserial_mgmt_pkt *pkt)
+{
+ pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_UNPLUG_RSP | FWSC_RSP_NACK);
+ pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code));
+}
+
+static inline void fill_unplug_rsp_ok(struct fwserial_mgmt_pkt *pkt)
+{
+ pkt->hdr.code = cpu_to_be16(FWSC_VIRT_CABLE_UNPLUG_RSP);
+ pkt->hdr.len = cpu_to_be16(mgmt_pkt_expected_len(pkt->hdr.code));
+}
+
+static void fwserial_virt_plug_complete(struct fwtty_peer *peer,
+ struct virt_plug_params *params)
+{
+ struct fwtty_port *port = peer->port;
+
+ peer->status_addr = be32_to_u64(params->status_hi, params->status_lo);
+ peer->fifo_addr = be32_to_u64(params->fifo_hi, params->fifo_lo);
+ peer->fifo_len = be32_to_cpu(params->fifo_len);
+ peer_set_state(peer, FWPS_ATTACHED);
+
+ /* reconfigure tx_fifo optimally for this peer */
+ spin_lock_bh(&port->lock);
+ port->max_payload = min(peer->max_payload, peer->fifo_len);
+ dma_fifo_change_tx_limit(&port->tx_fifo, port->max_payload);
+ spin_unlock_bh(&peer->port->lock);
+
+ if (port->port.console && port->fwcon_ops->notify != NULL)
+ (*port->fwcon_ops->notify)(FWCON_NOTIFY_ATTACH, port->con_data);
+
+ fwtty_info(&peer->unit, "peer (guid:%016llx) connected on %s\n",
+ (unsigned long long)peer->guid, dev_name(port->device));
+}
+
+static inline int fwserial_send_mgmt_sync(struct fwtty_peer *peer,
+ struct fwserial_mgmt_pkt *pkt)
+{
+ int generation;
+ int rcode, tries = 5;
+
+ do {
+ generation = peer->generation;
+ smp_rmb();
+
+ rcode = fw_run_transaction(peer->serial->card,
+ TCODE_WRITE_BLOCK_REQUEST,
+ peer->node_id,
+ generation, peer->speed,
+ peer->mgmt_addr,
+ pkt, be16_to_cpu(pkt->hdr.len));
+ if (rcode == RCODE_BUSY || rcode == RCODE_SEND_ERROR ||
+ rcode == RCODE_GENERATION) {
+ fwtty_dbg(&peer->unit, "mgmt write error: %d\n", rcode);
+ continue;
+ } else {
+ break;
+ }
+ } while (--tries > 0);
+ return rcode;
+}
+
+/**
+ * fwserial_claim_port - attempt to claim port @ index for peer
+ *
+ * Returns ptr to claimed port or error code (as ERR_PTR())
+ * Can sleep - must be called from process context
+ */
+static struct fwtty_port *fwserial_claim_port(struct fwtty_peer *peer,
+ int index)
+{
+ struct fwtty_port *port;
+
+ if (index < 0 || index >= num_ports)
+ return ERR_PTR(-EINVAL);
+
+ /* must guarantee that previous port releases have completed */
+ synchronize_rcu();
+
+ port = peer->serial->ports[index];
+ spin_lock_bh(&port->lock);
+ if (!rcu_access_pointer(port->peer))
+ rcu_assign_pointer(port->peer, peer);
+ else
+ port = ERR_PTR(-EBUSY);
+ spin_unlock_bh(&port->lock);
+
+ return port;
+}
+
+/**
+ * fwserial_find_port - find avail port and claim for peer
+ *
+ * Returns ptr to claimed port or NULL if none avail
+ * Can sleep - must be called from process context
+ */
+static struct fwtty_port *fwserial_find_port(struct fwtty_peer *peer)
+{
+ struct fwtty_port **ports = peer->serial->ports;
+ int i;
+
+ /* must guarantee that previous port releases have completed */
+ synchronize_rcu();
+
+ /* TODO: implement optional GUID-to-specific port # matching */
+
+ /* find an unattached port (but not the loopback port, if present) */
+ for (i = 0; i < num_ttys; ++i) {
+ spin_lock_bh(&ports[i]->lock);
+ if (!ports[i]->peer) {
+ /* claim port */
+ rcu_assign_pointer(ports[i]->peer, peer);
+ spin_unlock_bh(&ports[i]->lock);
+ return ports[i];
+ }
+ spin_unlock_bh(&ports[i]->lock);
+ }
+ return NULL;
+}
+
+static void fwserial_release_port(struct fwtty_port *port, bool reset)
+{
+ /* drop carrier (and all other line status) */
+ if (reset)
+ fwtty_update_port_status(port, 0);
+
+ spin_lock_bh(&port->lock);
+
+ /* reset dma fifo max transmission size back to S100 */
+ port->max_payload = link_speed_to_max_payload(SCODE_100);
+ dma_fifo_change_tx_limit(&port->tx_fifo, port->max_payload);
+
+ RCU_INIT_POINTER(port->peer, NULL);
+ spin_unlock_bh(&port->lock);
+
+ if (port->port.console && port->fwcon_ops->notify != NULL)
+ (*port->fwcon_ops->notify)(FWCON_NOTIFY_DETACH, port->con_data);
+}
+
+static void fwserial_plug_timeout(unsigned long data)
+{
+ struct fwtty_peer *peer = (struct fwtty_peer *)data;
+ struct fwtty_port *port;
+
+ spin_lock_bh(&peer->lock);
+ if (peer->state != FWPS_PLUG_PENDING) {
+ spin_unlock_bh(&peer->lock);
+ return;
+ }
+
+ port = peer_revert_state(peer);
+ spin_unlock_bh(&peer->lock);
+
+ if (port)
+ fwserial_release_port(port, false);
+}
+
+/**
+ * fwserial_connect_peer - initiate virtual cable with peer
+ *
+ * Returns 0 if VIRT_CABLE_PLUG request was successfully sent,
+ * otherwise error code. Must be called from process context.
+ */
+static int fwserial_connect_peer(struct fwtty_peer *peer)
+{
+ struct fwtty_port *port;
+ struct fwserial_mgmt_pkt *pkt;
+ int err, rcode;
+
+ pkt = kmalloc(sizeof(*pkt), GFP_KERNEL);
+ if (!pkt)
+ return -ENOMEM;
+
+ port = fwserial_find_port(peer);
+ if (!port) {
+ fwtty_err(&peer->unit, "avail ports in use\n");
+ err = -EBUSY;
+ goto free_pkt;
+ }
+
+ spin_lock_bh(&peer->lock);
+
+ /* only initiate VIRT_CABLE_PLUG if peer is currently not attached */
+ if (peer->state != FWPS_NOT_ATTACHED) {
+ err = -EBUSY;
+ goto release_port;
+ }
+
+ peer->port = port;
+ peer_set_state(peer, FWPS_PLUG_PENDING);
+
+ fill_plug_req(pkt, peer->port);
+
+ setup_timer(&peer->timer, fwserial_plug_timeout, (unsigned long)peer);
+ mod_timer(&peer->timer, jiffies + VIRT_CABLE_PLUG_TIMEOUT);
+ spin_unlock_bh(&peer->lock);
+
+ rcode = fwserial_send_mgmt_sync(peer, pkt);
+
+ spin_lock_bh(&peer->lock);
+ if (peer->state == FWPS_PLUG_PENDING && rcode != RCODE_COMPLETE) {
+ if (rcode == RCODE_CONFLICT_ERROR)
+ err = -EAGAIN;
+ else
+ err = -EIO;
+ goto cancel_timer;
+ }
+ spin_unlock_bh(&peer->lock);
+
+ kfree(pkt);
+ return 0;
+
+cancel_timer:
+ del_timer(&peer->timer);
+ peer_revert_state(peer);
+release_port:
+ spin_unlock_bh(&peer->lock);
+ fwserial_release_port(port, false);
+free_pkt:
+ kfree(pkt);
+ return err;
+}
+
+/**
+ * fwserial_close_port -
+ * HUP the tty (if the tty exists) and unregister the tty device.
+ * Only used by the unit driver upon unit removal to disconnect and
+ * cleanup all attached ports
+ *
+ * The port reference is put by fwtty_cleanup (if a reference was
+ * ever taken).
+ */
+static void fwserial_close_port(struct tty_driver *driver,
+ struct fwtty_port *port)
+{
+ struct tty_struct *tty;
+
+ mutex_lock(&port->port.mutex);
+ tty = tty_port_tty_get(&port->port);
+ if (tty) {
+ tty_vhangup(tty);
+ tty_kref_put(tty);
+ }
+ mutex_unlock(&port->port.mutex);
+
+ if (driver == fwloop_driver)
+ tty_unregister_device(driver, loop_idx(port));
+ else
+ tty_unregister_device(driver, port->index);
+}
+
+/**
+ * fwserial_lookup - finds first fw_serial associated with card
+ * @card: fw_card to match
+ *
+ * NB: caller must be holding fwserial_list_mutex
+ */
+static struct fw_serial *fwserial_lookup(struct fw_card *card)
+{
+ struct fw_serial *serial;
+
+ list_for_each_entry(serial, &fwserial_list, list) {
+ if (card == serial->card)
+ return serial;
+ }
+
+ return NULL;
+}
+
+/**
+ * __fwserial_lookup_rcu - finds first fw_serial associated with card
+ * @card: fw_card to match
+ *
+ * NB: caller must be inside rcu_read_lock() section
+ */
+static struct fw_serial *__fwserial_lookup_rcu(struct fw_card *card)
+{
+ struct fw_serial *serial;
+
+ list_for_each_entry_rcu(serial, &fwserial_list, list) {
+ if (card == serial->card)
+ return serial;
+ }
+
+ return NULL;
+}
+
+/**
+ * __fwserial_peer_by_node_id - finds a peer matching the given generation + id
+ *
+ * If a matching peer could not be found for the specified generation/node id,
+ * this could be because:
+ * a) the generation has changed and one of the nodes hasn't updated yet
+ * b) the remote node has created its remote unit device before this
+ * local node has created its corresponding remote unit device
+ * In either case, the remote node should retry
+ *
+ * Note: caller must be in rcu_read_lock() section
+ */
+static struct fwtty_peer *__fwserial_peer_by_node_id(struct fw_card *card,
+ int generation, int id)
+{
+ struct fw_serial *serial;
+ struct fwtty_peer *peer;
+
+ serial = __fwserial_lookup_rcu(card);
+ if (!serial) {
+ /*
+ * Something is very wrong - there should be a matching
+ * fw_serial structure for every fw_card. Maybe the remote node
+ * has created its remote unit device before this driver has
+ * been probed for any unit devices...
+ */
+ fwtty_err(card, "unknown card (guid %016llx)\n",
+ (unsigned long long) card->guid);
+ return NULL;
+ }
+
+ list_for_each_entry_rcu(peer, &serial->peer_list, list) {
+ int g = peer->generation;
+
+ smp_rmb();
+ if (generation == g && id == peer->node_id)
+ return peer;
+ }
+
+ return NULL;
+}
+
+#ifdef DEBUG
+static void __dump_peer_list(struct fw_card *card)
+{
+ struct fw_serial *serial;
+ struct fwtty_peer *peer;
+
+ serial = __fwserial_lookup_rcu(card);
+ if (!serial)
+ return;
+
+ list_for_each_entry_rcu(peer, &serial->peer_list, list) {
+ int g = peer->generation;
+
+ smp_rmb();
+ fwtty_dbg(card, "peer(%d:%x) guid: %016llx\n",
+ g, peer->node_id, (unsigned long long) peer->guid);
+ }
+}
+#else
+#define __dump_peer_list(s)
+#endif
+
+static void fwserial_auto_connect(struct work_struct *work)
+{
+ struct fwtty_peer *peer = to_peer(to_delayed_work(work), connect);
+ int err;
+
+ err = fwserial_connect_peer(peer);
+ if (err == -EAGAIN && ++peer->connect_retries < MAX_CONNECT_RETRIES)
+ schedule_delayed_work(&peer->connect, CONNECT_RETRY_DELAY);
+}
+
+static void fwserial_peer_workfn(struct work_struct *work)
+{
+ struct fwtty_peer *peer = to_peer(work, work);
+
+ peer->workfn(work);
+}
+
+/**
+ * fwserial_add_peer - add a newly probed 'serial' unit device as a 'peer'
+ * @serial: aggregate representing the specific fw_card to add the peer to
+ * @unit: 'peer' to create and add to peer_list of serial
+ *
+ * Adds a 'peer' (ie, a local or remote 'serial' unit device) to the list of
+ * peers for a specific fw_card. Optionally, auto-attach this peer to an
+ * available tty port. This function is called either directly or indirectly
+ * as a result of a 'serial' unit device being created & probed.
+ *
+ * Note: this function is serialized with fwserial_remove_peer() by the
+ * fwserial_list_mutex held in fwserial_probe().
+ *
+ * A 1:1 correspondence between an fw_unit and an fwtty_peer is maintained
+ * via the dev_set_drvdata() for the device of the fw_unit.
+ */
+static int fwserial_add_peer(struct fw_serial *serial, struct fw_unit *unit)
+{
+ struct device *dev = &unit->device;
+ struct fw_device *parent = fw_parent_device(unit);
+ struct fwtty_peer *peer;
+ struct fw_csr_iterator ci;
+ int key, val;
+ int generation;
+
+ peer = kzalloc(sizeof(*peer), GFP_KERNEL);
+ if (!peer)
+ return -ENOMEM;
+
+ peer_set_state(peer, FWPS_NOT_ATTACHED);
+
+ dev_set_drvdata(dev, peer);
+ peer->unit = unit;
+ peer->guid = (u64)parent->config_rom[3] << 32 | parent->config_rom[4];
+ peer->speed = parent->max_speed;
+ peer->max_payload = min(device_max_receive(parent),
+ link_speed_to_max_payload(peer->speed));
+
+ generation = parent->generation;
+ smp_rmb();
+ peer->node_id = parent->node_id;
+ smp_wmb();
+ peer->generation = generation;
+
+ /* retrieve the mgmt bus addr from the unit directory */
+ fw_csr_iterator_init(&ci, unit->directory);
+ while (fw_csr_iterator_next(&ci, &key, &val)) {
+ if (key == (CSR_OFFSET | CSR_DEPENDENT_INFO)) {
+ peer->mgmt_addr = CSR_REGISTER_BASE + 4 * val;
+ break;
+ }
+ }
+ if (peer->mgmt_addr == 0ULL) {
+ /*
+ * No mgmt address effectively disables VIRT_CABLE_PLUG -
+ * this peer will not be able to attach to a remote
+ */
+ peer_set_state(peer, FWPS_NO_MGMT_ADDR);
+ }
+
+ spin_lock_init(&peer->lock);
+ peer->port = NULL;
+
+ init_timer(&peer->timer);
+ INIT_WORK(&peer->work, fwserial_peer_workfn);
+ INIT_DELAYED_WORK(&peer->connect, fwserial_auto_connect);
+
+ /* associate peer with specific fw_card */
+ peer->serial = serial;
+ list_add_rcu(&peer->list, &serial->peer_list);
+
+ fwtty_info(&peer->unit, "peer added (guid:%016llx)\n",
+ (unsigned long long)peer->guid);
+
+ /* identify the local unit & virt cable to loopback port */
+ if (parent->is_local) {
+ serial->self = peer;
+ if (create_loop_dev) {
+ struct fwtty_port *port;
+
+ port = fwserial_claim_port(peer, num_ttys);
+ if (!IS_ERR(port)) {
+ struct virt_plug_params params;
+
+ spin_lock_bh(&peer->lock);
+ peer->port = port;
+ fill_plug_params(¶ms, port);
+ fwserial_virt_plug_complete(peer, ¶ms);
+ spin_unlock_bh(&peer->lock);
+
+ fwtty_write_port_status(port);
+ }
+ }
+
+ } else if (auto_connect) {
+ /* auto-attach to remote units only (if policy allows) */
+ schedule_delayed_work(&peer->connect, 1);
+ }
+
+ return 0;
+}
+
+/**
+ * fwserial_remove_peer - remove a 'serial' unit device as a 'peer'
+ *
+ * Remove a 'peer' from its list of peers. This function is only
+ * called by fwserial_remove() on bus removal of the unit device.
+ *
+ * Note: this function is serialized with fwserial_add_peer() by the
+ * fwserial_list_mutex held in fwserial_remove().
+ */
+static void fwserial_remove_peer(struct fwtty_peer *peer)
+{
+ struct fwtty_port *port;
+
+ spin_lock_bh(&peer->lock);
+ peer_set_state(peer, FWPS_GONE);
+ spin_unlock_bh(&peer->lock);
+
+ cancel_delayed_work_sync(&peer->connect);
+ cancel_work_sync(&peer->work);
+
+ spin_lock_bh(&peer->lock);
+ /* if this unit is the local unit, clear link */
+ if (peer == peer->serial->self)
+ peer->serial->self = NULL;
+
+ /* cancel the request timeout timer (if running) */
+ del_timer(&peer->timer);
+
+ port = peer->port;
+ peer->port = NULL;
+
+ list_del_rcu(&peer->list);
+
+ fwtty_info(&peer->unit, "peer removed (guid:%016llx)\n",
+ (unsigned long long)peer->guid);
+
+ spin_unlock_bh(&peer->lock);
+
+ if (port)
+ fwserial_release_port(port, true);
+
+ synchronize_rcu();
+ kfree(peer);
+}
+
+/**
+ * fwserial_create - init everything to create TTYs for a specific fw_card
+ * @unit: fw_unit for first 'serial' unit device probed for this fw_card
+ *
+ * This function inits the aggregate structure (an fw_serial instance)
+ * used to manage the TTY ports registered by a specific fw_card. Also, the
+ * unit device is added as the first 'peer'.
+ *
+ * This unit device may represent a local unit device (as specified by the
+ * config ROM unit directory) or it may represent a remote unit device
+ * (as specified by the reading of the remote node's config ROM).
+ *
+ * Returns 0 to indicate "ownership" of the unit device, or a negative errno
+ * value to indicate which error.
+ */
+static int fwserial_create(struct fw_unit *unit)
+{
+ struct fw_device *parent = fw_parent_device(unit);
+ struct fw_card *card = parent->card;
+ struct fw_serial *serial;
+ struct fwtty_port *port;
+ struct device *tty_dev;
+ int i, j;
+ int err;
+
+ serial = kzalloc(sizeof(*serial), GFP_KERNEL);
+ if (!serial)
+ return -ENOMEM;
+
+ kref_init(&serial->kref);
+ serial->card = card;
+ INIT_LIST_HEAD(&serial->peer_list);
+
+ for (i = 0; i < num_ports; ++i) {
+ port = kzalloc(sizeof(*port), GFP_KERNEL);
+ if (!port) {
+ err = -ENOMEM;
+ goto free_ports;
+ }
+ tty_port_init(&port->port);
+ port->index = FWTTY_INVALID_INDEX;
+ port->port.ops = &fwtty_port_ops;
+ port->serial = serial;
+ tty_buffer_set_limit(&port->port, 128 * 1024);
+
+ spin_lock_init(&port->lock);
+ INIT_DELAYED_WORK(&port->drain, fwtty_drain_tx);
+ INIT_DELAYED_WORK(&port->emit_breaks, fwtty_emit_breaks);
+ INIT_WORK(&port->hangup, fwtty_do_hangup);
+ init_waitqueue_head(&port->wait_tx);
+ port->max_payload = link_speed_to_max_payload(SCODE_100);
+ dma_fifo_init(&port->tx_fifo);
+
+ RCU_INIT_POINTER(port->peer, NULL);
+ serial->ports[i] = port;
+
+ /* get unique bus addr region for port's status & recv fifo */
+ port->rx_handler.length = FWTTY_PORT_RXFIFO_LEN + 4;
+ port->rx_handler.address_callback = fwtty_port_handler;
+ port->rx_handler.callback_data = port;
+ /*
+ * XXX: use custom memory region above cpu physical memory addrs
+ * this will ease porting to 64-bit firewire adapters
+ */
+ err = fw_core_add_address_handler(&port->rx_handler,
+ &fw_high_memory_region);
+ if (err) {
+ kfree(port);
+ goto free_ports;
+ }
+ }
+ /* preserve i for error cleanup */
+
+ err = fwtty_ports_add(serial);
+ if (err) {
+ fwtty_err(&unit, "no space in port table\n");
+ goto free_ports;
+ }
+
+ for (j = 0; j < num_ttys; ++j) {
+ tty_dev = tty_port_register_device(&serial->ports[j]->port,
+ fwtty_driver,
+ serial->ports[j]->index,
+ card->device);
+ if (IS_ERR(tty_dev)) {
+ err = PTR_ERR(tty_dev);
+ fwtty_err(&unit, "register tty device error (%d)\n",
+ err);
+ goto unregister_ttys;
+ }
+
+ serial->ports[j]->device = tty_dev;
+ }
+ /* preserve j for error cleanup */
+
+ if (create_loop_dev) {
+ struct device *loop_dev;
+
+ loop_dev = tty_port_register_device(&serial->ports[j]->port,
+ fwloop_driver,
+ loop_idx(serial->ports[j]),
+ card->device);
+ if (IS_ERR(loop_dev)) {
+ err = PTR_ERR(loop_dev);
+ fwtty_err(&unit, "create loop device failed (%d)\n",
+ err);
+ goto unregister_ttys;
+ }
+ serial->ports[j]->device = loop_dev;
+ serial->ports[j]->loopback = true;
+ }
+
+ if (!IS_ERR_OR_NULL(fwserial_debugfs)) {
+ serial->debugfs = debugfs_create_dir(dev_name(&unit->device),
+ fwserial_debugfs);
+ if (!IS_ERR_OR_NULL(serial->debugfs)) {
+ debugfs_create_file("peers", 0444, serial->debugfs,
+ serial, &fwtty_peers_fops);
+ debugfs_create_file("stats", 0444, serial->debugfs,
+ serial, &fwtty_stats_fops);
+ }
+ }
+
+ list_add_rcu(&serial->list, &fwserial_list);
+
+ fwtty_notice(&unit, "TTY over FireWire on device %s (guid %016llx)\n",
+ dev_name(card->device), (unsigned long long) card->guid);
+
+ err = fwserial_add_peer(serial, unit);
+ if (!err)
+ return 0;
+
+ fwtty_err(&unit, "unable to add peer unit device (%d)\n", err);
+
+ /* fall-through to error processing */
+ debugfs_remove_recursive(serial->debugfs);
+
+ list_del_rcu(&serial->list);
+ if (create_loop_dev)
+ tty_unregister_device(fwloop_driver,
+ loop_idx(serial->ports[j]));
+unregister_ttys:
+ for (--j; j >= 0; --j)
+ tty_unregister_device(fwtty_driver, serial->ports[j]->index);
+ kref_put(&serial->kref, fwserial_destroy);
+ return err;
+
+free_ports:
+ for (--i; i >= 0; --i) {
+ tty_port_destroy(&serial->ports[i]->port);
+ kfree(serial->ports[i]);
+ }
+ kfree(serial);
+ return err;
+}
+
+/**
+ * fwserial_probe: bus probe function for firewire 'serial' unit devices
+ *
+ * A 'serial' unit device is created and probed as a result of:
+ * - declaring a ieee1394 bus id table for 'devices' matching a fabricated
+ * 'serial' unit specifier id
+ * - adding a unit directory to the config ROM(s) for a 'serial' unit
+ *
+ * The firewire core registers unit devices by enumerating unit directories
+ * of a node's config ROM after reading the config ROM when a new node is
+ * added to the bus topology after a bus reset.
+ *
+ * The practical implications of this are:
+ * - this probe is called for both local and remote nodes that have a 'serial'
+ * unit directory in their config ROM (that matches the specifiers in
+ * fwserial_id_table).
+ * - no specific order is enforced for local vs. remote unit devices
+ *
+ * This unit driver copes with the lack of specific order in the same way the
+ * firewire net driver does -- each probe, for either a local or remote unit
+ * device, is treated as a 'peer' (has a struct fwtty_peer instance) and the
+ * first peer created for a given fw_card (tracked by the global fwserial_list)
+ * creates the underlying TTYs (aggregated in a fw_serial instance).
+ *
+ * NB: an early attempt to differentiate local & remote unit devices by creating
+ * peers only for remote units and fw_serial instances (with their
+ * associated TTY devices) only for local units was discarded. Managing
+ * the peer lifetimes on device removal proved too complicated.
+ *
+ * fwserial_probe/fwserial_remove are effectively serialized by the
+ * fwserial_list_mutex. This is necessary because the addition of the first peer
+ * for a given fw_card will trigger the creation of the fw_serial for that
+ * fw_card, which must not simultaneously contend with the removal of the
+ * last peer for a given fw_card triggering the destruction of the same
+ * fw_serial for the same fw_card.
+ */
+static int fwserial_probe(struct fw_unit *unit,
+ const struct ieee1394_device_id *id)
+{
+ struct fw_serial *serial;
+ int err;
+
+ mutex_lock(&fwserial_list_mutex);
+ serial = fwserial_lookup(fw_parent_device(unit)->card);
+ if (!serial)
+ err = fwserial_create(unit);
+ else
+ err = fwserial_add_peer(serial, unit);
+ mutex_unlock(&fwserial_list_mutex);
+ return err;
+}
+
+/**
+ * fwserial_remove: bus removal function for firewire 'serial' unit devices
+ *
+ * The corresponding 'peer' for this unit device is removed from the list of
+ * peers for the associated fw_serial (which has a 1:1 correspondence with a
+ * specific fw_card). If this is the last peer being removed, then trigger
+ * the destruction of the underlying TTYs.
+ */
+static void fwserial_remove(struct fw_unit *unit)
+{
+ struct fwtty_peer *peer = dev_get_drvdata(&unit->device);
+ struct fw_serial *serial = peer->serial;
+ int i;
+
+ mutex_lock(&fwserial_list_mutex);
+ fwserial_remove_peer(peer);
+
+ if (list_empty(&serial->peer_list)) {
+ /* unlink from the fwserial_list here */
+ list_del_rcu(&serial->list);
+
+ debugfs_remove_recursive(serial->debugfs);
+
+ for (i = 0; i < num_ttys; ++i)
+ fwserial_close_port(fwtty_driver, serial->ports[i]);
+ if (create_loop_dev)
+ fwserial_close_port(fwloop_driver, serial->ports[i]);
+ kref_put(&serial->kref, fwserial_destroy);
+ }
+ mutex_unlock(&fwserial_list_mutex);
+}
+
+/**
+ * fwserial_update: bus update function for 'firewire' serial unit devices
+ *
+ * Updates the new node_id and bus generation for this peer. Note that locking
+ * is unnecessary; but careful memory barrier usage is important to enforce the
+ * load and store order of generation & node_id.
+ *
+ * The fw-core orders the write of node_id before generation in the parent
+ * fw_device to ensure that a stale node_id cannot be used with a current
+ * bus generation. So the generation value must be read before the node_id.
+ *
+ * In turn, this orders the write of node_id before generation in the peer to
+ * also ensure a stale node_id cannot be used with a current bus generation.
+ */
+static void fwserial_update(struct fw_unit *unit)
+{
+ struct fw_device *parent = fw_parent_device(unit);
+ struct fwtty_peer *peer = dev_get_drvdata(&unit->device);
+ int generation;
+
+ generation = parent->generation;
+ smp_rmb();
+ peer->node_id = parent->node_id;
+ smp_wmb();
+ peer->generation = generation;
+}
+
+static const struct ieee1394_device_id fwserial_id_table[] = {
+ {
+ .match_flags = IEEE1394_MATCH_SPECIFIER_ID |
+ IEEE1394_MATCH_VERSION,
+ .specifier_id = LINUX_VENDOR_ID,
+ .version = FWSERIAL_VERSION,
+ },
+ { }
+};
+
+static struct fw_driver fwserial_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = KBUILD_MODNAME,
+ .bus = &fw_bus_type,
+ },
+ .probe = fwserial_probe,
+ .update = fwserial_update,
+ .remove = fwserial_remove,
+ .id_table = fwserial_id_table,
+};
+
+#define FW_UNIT_SPECIFIER(id) ((CSR_SPECIFIER_ID << 24) | (id))
+#define FW_UNIT_VERSION(ver) ((CSR_VERSION << 24) | (ver))
+#define FW_UNIT_ADDRESS(ofs) (((CSR_OFFSET | CSR_DEPENDENT_INFO) << 24) \
+ | (((ofs) - CSR_REGISTER_BASE) >> 2))
+/* XXX: config ROM definitons could be improved with semi-automated offset
+ * and length calculation
+ */
+#define FW_ROM_LEN(quads) ((quads) << 16)
+#define FW_ROM_DESCRIPTOR(ofs) (((CSR_LEAF | CSR_DESCRIPTOR) << 24) | (ofs))
+
+struct fwserial_unit_directory_data {
+ u32 len_crc;
+ u32 unit_specifier;
+ u32 unit_sw_version;
+ u32 unit_addr_offset;
+ u32 desc1_ofs;
+ u32 desc1_len_crc;
+ u32 desc1_data[5];
+} __packed;
+
+static struct fwserial_unit_directory_data fwserial_unit_directory_data = {
+ .len_crc = FW_ROM_LEN(4),
+ .unit_specifier = FW_UNIT_SPECIFIER(LINUX_VENDOR_ID),
+ .unit_sw_version = FW_UNIT_VERSION(FWSERIAL_VERSION),
+ .desc1_ofs = FW_ROM_DESCRIPTOR(1),
+ .desc1_len_crc = FW_ROM_LEN(5),
+ .desc1_data = {
+ 0x00000000, /* type = text */
+ 0x00000000, /* enc = ASCII, lang EN */
+ 0x4c696e75, /* 'Linux TTY' */
+ 0x78205454,
+ 0x59000000,
+ },
+};
+
+static struct fw_descriptor fwserial_unit_directory = {
+ .length = sizeof(fwserial_unit_directory_data) / sizeof(u32),
+ .key = (CSR_DIRECTORY | CSR_UNIT) << 24,
+ .data = (u32 *)&fwserial_unit_directory_data,
+};
+
+/*
+ * The management address is in the unit space region but above other known
+ * address users (to keep wild writes from causing havoc)
+ */
+static const struct fw_address_region fwserial_mgmt_addr_region = {
+ .start = CSR_REGISTER_BASE + 0x1e0000ULL,
+ .end = 0x1000000000000ULL,
+};
+
+static struct fw_address_handler fwserial_mgmt_addr_handler;
+
+/**
+ * fwserial_handle_plug_req - handle VIRT_CABLE_PLUG request work
+ * @work: ptr to peer->work
+ *
+ * Attempts to complete the VIRT_CABLE_PLUG handshake sequence for this peer.
+ *
+ * This checks for a collided request-- ie, that a VIRT_CABLE_PLUG request was
+ * already sent to this peer. If so, the collision is resolved by comparing
+ * guid values; the loser sends the plug response.
+ *
+ * Note: if an error prevents a response, don't do anything -- the
+ * remote will timeout its request.
+ */
+static void fwserial_handle_plug_req(struct work_struct *work)
+{
+ struct fwtty_peer *peer = to_peer(work, work);
+ struct virt_plug_params *plug_req = &peer->work_params.plug_req;
+ struct fwtty_port *port;
+ struct fwserial_mgmt_pkt *pkt;
+ int rcode;
+
+ pkt = kmalloc(sizeof(*pkt), GFP_KERNEL);
+ if (!pkt)
+ return;
+
+ port = fwserial_find_port(peer);
+
+ spin_lock_bh(&peer->lock);
+
+ switch (peer->state) {
+ case FWPS_NOT_ATTACHED:
+ if (!port) {
+ fwtty_err(&peer->unit, "no more ports avail\n");
+ fill_plug_rsp_nack(pkt);
+ } else {
+ peer->port = port;
+ fill_plug_rsp_ok(pkt, peer->port);
+ peer_set_state(peer, FWPS_PLUG_RESPONDING);
+ /* don't release claimed port */
+ port = NULL;
+ }
+ break;
+
+ case FWPS_PLUG_PENDING:
+ if (peer->serial->card->guid > peer->guid)
+ goto cleanup;
+
+ /* We lost - hijack the already-claimed port and send ok */
+ del_timer(&peer->timer);
+ fill_plug_rsp_ok(pkt, peer->port);
+ peer_set_state(peer, FWPS_PLUG_RESPONDING);
+ break;
+
+ default:
+ fill_plug_rsp_nack(pkt);
+ }
+
+ spin_unlock_bh(&peer->lock);
+ if (port)
+ fwserial_release_port(port, false);
+
+ rcode = fwserial_send_mgmt_sync(peer, pkt);
+
+ spin_lock_bh(&peer->lock);
+ if (peer->state == FWPS_PLUG_RESPONDING) {
+ if (rcode == RCODE_COMPLETE) {
+ struct fwtty_port *tmp = peer->port;
+
+ fwserial_virt_plug_complete(peer, plug_req);
+ spin_unlock_bh(&peer->lock);
+
+ fwtty_write_port_status(tmp);
+ spin_lock_bh(&peer->lock);
+ } else {
+ fwtty_err(&peer->unit, "PLUG_RSP error (%d)\n", rcode);
+ port = peer_revert_state(peer);
+ }
+ }
+cleanup:
+ spin_unlock_bh(&peer->lock);
+ if (port)
+ fwserial_release_port(port, false);
+ kfree(pkt);
+}
+
+static void fwserial_handle_unplug_req(struct work_struct *work)
+{
+ struct fwtty_peer *peer = to_peer(work, work);
+ struct fwtty_port *port = NULL;
+ struct fwserial_mgmt_pkt *pkt;
+ int rcode;
+
+ pkt = kmalloc(sizeof(*pkt), GFP_KERNEL);
+ if (!pkt)
+ return;
+
+ spin_lock_bh(&peer->lock);
+
+ switch (peer->state) {
+ case FWPS_ATTACHED:
+ fill_unplug_rsp_ok(pkt);
+ peer_set_state(peer, FWPS_UNPLUG_RESPONDING);
+ break;
+
+ case FWPS_UNPLUG_PENDING:
+ if (peer->serial->card->guid > peer->guid)
+ goto cleanup;
+
+ /* We lost - send unplug rsp */
+ del_timer(&peer->timer);
+ fill_unplug_rsp_ok(pkt);
+ peer_set_state(peer, FWPS_UNPLUG_RESPONDING);
+ break;
+
+ default:
+ fill_unplug_rsp_nack(pkt);
+ }
+
+ spin_unlock_bh(&peer->lock);
+
+ rcode = fwserial_send_mgmt_sync(peer, pkt);
+
+ spin_lock_bh(&peer->lock);
+ if (peer->state == FWPS_UNPLUG_RESPONDING) {
+ if (rcode != RCODE_COMPLETE)
+ fwtty_err(&peer->unit, "UNPLUG_RSP error (%d)\n",
+ rcode);
+ port = peer_revert_state(peer);
+ }
+cleanup:
+ spin_unlock_bh(&peer->lock);
+ if (port)
+ fwserial_release_port(port, true);
+ kfree(pkt);
+}
+
+static int fwserial_parse_mgmt_write(struct fwtty_peer *peer,
+ struct fwserial_mgmt_pkt *pkt,
+ unsigned long long addr,
+ size_t len)
+{
+ struct fwtty_port *port = NULL;
+ bool reset = false;
+ int rcode;
+
+ if (addr != fwserial_mgmt_addr_handler.offset || len < sizeof(pkt->hdr))
+ return RCODE_ADDRESS_ERROR;
+
+ if (len != be16_to_cpu(pkt->hdr.len) ||
+ len != mgmt_pkt_expected_len(pkt->hdr.code))
+ return RCODE_DATA_ERROR;
+
+ spin_lock_bh(&peer->lock);
+ if (peer->state == FWPS_GONE) {
+ /*
+ * This should never happen - it would mean that the
+ * remote unit that just wrote this transaction was
+ * already removed from the bus -- and the removal was
+ * processed before we rec'd this transaction
+ */
+ fwtty_err(&peer->unit, "peer already removed\n");
+ spin_unlock_bh(&peer->lock);
+ return RCODE_ADDRESS_ERROR;
+ }
+
+ rcode = RCODE_COMPLETE;
+
+ fwtty_dbg(&peer->unit, "mgmt: hdr.code: %04hx\n", pkt->hdr.code);
+
+ switch (be16_to_cpu(pkt->hdr.code) & FWSC_CODE_MASK) {
+ case FWSC_VIRT_CABLE_PLUG:
+ if (work_pending(&peer->work)) {
+ fwtty_err(&peer->unit, "plug req: busy\n");
+ rcode = RCODE_CONFLICT_ERROR;
+
+ } else {
+ peer->work_params.plug_req = pkt->plug_req;
+ peer->workfn = fwserial_handle_plug_req;
+ queue_work(system_unbound_wq, &peer->work);
+ }
+ break;
+
+ case FWSC_VIRT_CABLE_PLUG_RSP:
+ if (peer->state != FWPS_PLUG_PENDING) {
+ rcode = RCODE_CONFLICT_ERROR;
+
+ } else if (be16_to_cpu(pkt->hdr.code) & FWSC_RSP_NACK) {
+ fwtty_notice(&peer->unit, "NACK plug rsp\n");
+ port = peer_revert_state(peer);
+
+ } else {
+ struct fwtty_port *tmp = peer->port;
+
+ fwserial_virt_plug_complete(peer, &pkt->plug_rsp);
+ spin_unlock_bh(&peer->lock);
+
+ fwtty_write_port_status(tmp);
+ spin_lock_bh(&peer->lock);
+ }
+ break;
+
+ case FWSC_VIRT_CABLE_UNPLUG:
+ if (work_pending(&peer->work)) {
+ fwtty_err(&peer->unit, "unplug req: busy\n");
+ rcode = RCODE_CONFLICT_ERROR;
+ } else {
+ peer->workfn = fwserial_handle_unplug_req;
+ queue_work(system_unbound_wq, &peer->work);
+ }
+ break;
+
+ case FWSC_VIRT_CABLE_UNPLUG_RSP:
+ if (peer->state != FWPS_UNPLUG_PENDING) {
+ rcode = RCODE_CONFLICT_ERROR;
+ } else {
+ if (be16_to_cpu(pkt->hdr.code) & FWSC_RSP_NACK)
+ fwtty_notice(&peer->unit, "NACK unplug?\n");
+ port = peer_revert_state(peer);
+ reset = true;
+ }
+ break;
+
+ default:
+ fwtty_err(&peer->unit, "unknown mgmt code %d\n",
+ be16_to_cpu(pkt->hdr.code));
+ rcode = RCODE_DATA_ERROR;
+ }
+ spin_unlock_bh(&peer->lock);
+
+ if (port)
+ fwserial_release_port(port, reset);
+
+ return rcode;
+}
+
+/**
+ * fwserial_mgmt_handler: bus address handler for mgmt requests
+ * @parameters: fw_address_callback_t as specified by firewire core interface
+ *
+ * This handler is responsible for handling virtual cable requests from remotes
+ * for all cards.
+ */
+static void fwserial_mgmt_handler(struct fw_card *card,
+ struct fw_request *request,
+ int tcode, int destination, int source,
+ int generation,
+ unsigned long long addr,
+ void *data, size_t len,
+ void *callback_data)
+{
+ struct fwserial_mgmt_pkt *pkt = data;
+ struct fwtty_peer *peer;
+ int rcode;
+
+ rcu_read_lock();
+ peer = __fwserial_peer_by_node_id(card, generation, source);
+ if (!peer) {
+ fwtty_dbg(card, "peer(%d:%x) not found\n", generation, source);
+ __dump_peer_list(card);
+ rcode = RCODE_CONFLICT_ERROR;
+
+ } else {
+ switch (tcode) {
+ case TCODE_WRITE_BLOCK_REQUEST:
+ rcode = fwserial_parse_mgmt_write(peer, pkt, addr, len);
+ break;
+
+ default:
+ rcode = RCODE_TYPE_ERROR;
+ }
+ }
+
+ rcu_read_unlock();
+ fw_send_response(card, request, rcode);
+}
+
+static int __init fwserial_init(void)
+{
+ int err, num_loops = !!(create_loop_dev);
+
+ /* XXX: placeholder for a "firewire" debugfs node */
+ fwserial_debugfs = debugfs_create_dir(KBUILD_MODNAME, NULL);
+
+ /* num_ttys/num_ports must not be set above the static alloc avail */
+ if (num_ttys + num_loops > MAX_CARD_PORTS)
+ num_ttys = MAX_CARD_PORTS - num_loops;
+ num_ports = num_ttys + num_loops;
+
+ fwtty_driver = tty_alloc_driver(MAX_TOTAL_PORTS, TTY_DRIVER_REAL_RAW
+ | TTY_DRIVER_DYNAMIC_DEV);
+ if (IS_ERR(fwtty_driver)) {
+ err = PTR_ERR(fwtty_driver);
+ return err;
+ }
+
+ fwtty_driver->driver_name = KBUILD_MODNAME;
+ fwtty_driver->name = tty_dev_name;
+ fwtty_driver->major = 0;
+ fwtty_driver->minor_start = 0;
+ fwtty_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ fwtty_driver->subtype = SERIAL_TYPE_NORMAL;
+ fwtty_driver->init_termios = tty_std_termios;
+ fwtty_driver->init_termios.c_cflag |= CLOCAL;
+ tty_set_operations(fwtty_driver, &fwtty_ops);
+
+ err = tty_register_driver(fwtty_driver);
+ if (err) {
+ pr_err("register tty driver failed (%d)\n", err);
+ goto put_tty;
+ }
+
+ if (create_loop_dev) {
+ fwloop_driver = tty_alloc_driver(MAX_TOTAL_PORTS / num_ports,
+ TTY_DRIVER_REAL_RAW
+ | TTY_DRIVER_DYNAMIC_DEV);
+ if (IS_ERR(fwloop_driver)) {
+ err = PTR_ERR(fwloop_driver);
+ goto unregister_driver;
+ }
+
+ fwloop_driver->driver_name = KBUILD_MODNAME "_loop";
+ fwloop_driver->name = loop_dev_name;
+ fwloop_driver->major = 0;
+ fwloop_driver->minor_start = 0;
+ fwloop_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ fwloop_driver->subtype = SERIAL_TYPE_NORMAL;
+ fwloop_driver->init_termios = tty_std_termios;
+ fwloop_driver->init_termios.c_cflag |= CLOCAL;
+ tty_set_operations(fwloop_driver, &fwloop_ops);
+
+ err = tty_register_driver(fwloop_driver);
+ if (err) {
+ pr_err("register loop driver failed (%d)\n", err);
+ goto put_loop;
+ }
+ }
+
+ fwtty_txn_cache = kmem_cache_create("fwtty_txn_cache",
+ sizeof(struct fwtty_transaction),
+ 0, 0, fwtty_txn_constructor);
+ if (!fwtty_txn_cache) {
+ err = -ENOMEM;
+ goto unregister_loop;
+ }
+
+ /*
+ * Ideally, this address handler would be registered per local node
+ * (rather than the same handler for all local nodes). However,
+ * since the firewire core requires the config rom descriptor *before*
+ * the local unit device(s) are created, a single management handler
+ * must suffice for all local serial units.
+ */
+ fwserial_mgmt_addr_handler.length = sizeof(struct fwserial_mgmt_pkt);
+ fwserial_mgmt_addr_handler.address_callback = fwserial_mgmt_handler;
+
+ err = fw_core_add_address_handler(&fwserial_mgmt_addr_handler,
+ &fwserial_mgmt_addr_region);
+ if (err) {
+ pr_err("add management handler failed (%d)\n", err);
+ goto destroy_cache;
+ }
+
+ fwserial_unit_directory_data.unit_addr_offset =
+ FW_UNIT_ADDRESS(fwserial_mgmt_addr_handler.offset);
+ err = fw_core_add_descriptor(&fwserial_unit_directory);
+ if (err) {
+ pr_err("add unit descriptor failed (%d)\n", err);
+ goto remove_handler;
+ }
+
+ err = driver_register(&fwserial_driver.driver);
+ if (err) {
+ pr_err("register fwserial driver failed (%d)\n", err);
+ goto remove_descriptor;
+ }
+
+ return 0;
+
+remove_descriptor:
+ fw_core_remove_descriptor(&fwserial_unit_directory);
+remove_handler:
+ fw_core_remove_address_handler(&fwserial_mgmt_addr_handler);
+destroy_cache:
+ kmem_cache_destroy(fwtty_txn_cache);
+unregister_loop:
+ if (create_loop_dev)
+ tty_unregister_driver(fwloop_driver);
+put_loop:
+ if (create_loop_dev)
+ put_tty_driver(fwloop_driver);
+unregister_driver:
+ tty_unregister_driver(fwtty_driver);
+put_tty:
+ put_tty_driver(fwtty_driver);
+ debugfs_remove_recursive(fwserial_debugfs);
+ return err;
+}
+
+static void __exit fwserial_exit(void)
+{
+ driver_unregister(&fwserial_driver.driver);
+ fw_core_remove_descriptor(&fwserial_unit_directory);
+ fw_core_remove_address_handler(&fwserial_mgmt_addr_handler);
+ kmem_cache_destroy(fwtty_txn_cache);
+ if (create_loop_dev) {
+ tty_unregister_driver(fwloop_driver);
+ put_tty_driver(fwloop_driver);
+ }
+ tty_unregister_driver(fwtty_driver);
+ put_tty_driver(fwtty_driver);
+ debugfs_remove_recursive(fwserial_debugfs);
+}
+
+module_init(fwserial_init);
+module_exit(fwserial_exit);
+
+MODULE_AUTHOR("Peter Hurley (peter@hurleysoftware.com)");
+MODULE_DESCRIPTION("FireWire Serial TTY Driver");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(ieee1394, fwserial_id_table);
+MODULE_PARM_DESC(ttys, "Number of ttys to create for each local firewire node");
+MODULE_PARM_DESC(auto, "Auto-connect a tty to each firewire node discovered");
+MODULE_PARM_DESC(loop, "Create a loopback device, fwloop<n>, with ttys");
Code Review / kvmfornfv.git / blobdiff