diff options
Diffstat (limited to 'drivers/isdn/gigaset/ser-gigaset.c')
| -rw-r--r-- | drivers/isdn/gigaset/ser-gigaset.c | 799 |
1 files changed, 799 insertions, 0 deletions
diff --git a/drivers/isdn/gigaset/ser-gigaset.c b/drivers/isdn/gigaset/ser-gigaset.c new file mode 100644 index 000000000..ab0b63a4d --- /dev/null +++ b/drivers/isdn/gigaset/ser-gigaset.c @@ -0,0 +1,799 @@ +/* This is the serial hardware link layer (HLL) for the Gigaset 307x isdn + * DECT base (aka Sinus 45 isdn) using the RS232 DECT data module M101, + * written as a line discipline. + * + * ===================================================================== + * 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. + * ===================================================================== + */ + +#include "gigaset.h" +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/platform_device.h> +#include <linux/completion.h> + +/* Version Information */ +#define DRIVER_AUTHOR "Tilman Schmidt" +#define DRIVER_DESC "Serial Driver for Gigaset 307x using Siemens M101" + +#define GIGASET_MINORS 1 +#define GIGASET_MINOR 0 +#define GIGASET_MODULENAME "ser_gigaset" +#define GIGASET_DEVNAME "ttyGS" + +/* length limit according to Siemens 3070usb-protokoll.doc ch. 2.1 */ +#define IF_WRITEBUF 264 + +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_LDISC(N_GIGASET_M101); + +static int startmode = SM_ISDN; +module_param(startmode, int, S_IRUGO); +MODULE_PARM_DESC(startmode, "initial operation mode"); +static int cidmode = 1; +module_param(cidmode, int, S_IRUGO); +MODULE_PARM_DESC(cidmode, "stay in CID mode when idle"); + +static struct gigaset_driver *driver; + +struct ser_cardstate { + struct platform_device dev; + struct tty_struct *tty; + atomic_t refcnt; + struct completion dead_cmp; +}; + +static struct platform_driver device_driver = { + .driver = { + .name = GIGASET_MODULENAME, + }, +}; + +static void flush_send_queue(struct cardstate *); + +/* transmit data from current open skb + * result: number of bytes sent or error code < 0 + */ +static int write_modem(struct cardstate *cs) +{ + struct tty_struct *tty = cs->hw.ser->tty; + struct bc_state *bcs = &cs->bcs[0]; /* only one channel */ + struct sk_buff *skb = bcs->tx_skb; + int sent = -EOPNOTSUPP; + + WARN_ON(!tty || !tty->ops || !skb); + + if (!skb->len) { + dev_kfree_skb_any(skb); + bcs->tx_skb = NULL; + return -EINVAL; + } + + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + if (tty->ops->write) + sent = tty->ops->write(tty, skb->data, skb->len); + gig_dbg(DEBUG_OUTPUT, "write_modem: sent %d", sent); + if (sent < 0) { + /* error */ + flush_send_queue(cs); + return sent; + } + skb_pull(skb, sent); + if (!skb->len) { + /* skb sent completely */ + gigaset_skb_sent(bcs, skb); + + gig_dbg(DEBUG_INTR, "kfree skb (Adr: %lx)!", + (unsigned long) skb); + dev_kfree_skb_any(skb); + bcs->tx_skb = NULL; + } + return sent; +} + +/* + * transmit first queued command buffer + * result: number of bytes sent or error code < 0 + */ +static int send_cb(struct cardstate *cs) +{ + struct tty_struct *tty = cs->hw.ser->tty; + struct cmdbuf_t *cb, *tcb; + unsigned long flags; + int sent = 0; + + WARN_ON(!tty || !tty->ops); + + cb = cs->cmdbuf; + if (!cb) + return 0; /* nothing to do */ + + if (cb->len) { + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + sent = tty->ops->write(tty, cb->buf + cb->offset, cb->len); + if (sent < 0) { + /* error */ + gig_dbg(DEBUG_OUTPUT, "send_cb: write error %d", sent); + flush_send_queue(cs); + return sent; + } + cb->offset += sent; + cb->len -= sent; + gig_dbg(DEBUG_OUTPUT, "send_cb: sent %d, left %u, queued %u", + sent, cb->len, cs->cmdbytes); + } + + while (cb && !cb->len) { + spin_lock_irqsave(&cs->cmdlock, flags); + cs->cmdbytes -= cs->curlen; + tcb = cb; + cs->cmdbuf = cb = cb->next; + if (cb) { + cb->prev = NULL; + cs->curlen = cb->len; + } else { + cs->lastcmdbuf = NULL; + cs->curlen = 0; + } + spin_unlock_irqrestore(&cs->cmdlock, flags); + + if (tcb->wake_tasklet) + tasklet_schedule(tcb->wake_tasklet); + kfree(tcb); + } + return sent; +} + +/* + * send queue tasklet + * If there is already a skb opened, put data to the transfer buffer + * by calling "write_modem". + * Otherwise take a new skb out of the queue. + */ +static void gigaset_modem_fill(unsigned long data) +{ + struct cardstate *cs = (struct cardstate *) data; + struct bc_state *bcs; + struct sk_buff *nextskb; + int sent = 0; + + if (!cs) { + gig_dbg(DEBUG_OUTPUT, "%s: no cardstate", __func__); + return; + } + bcs = cs->bcs; + if (!bcs) { + gig_dbg(DEBUG_OUTPUT, "%s: no cardstate", __func__); + return; + } + if (!bcs->tx_skb) { + /* no skb is being sent; send command if any */ + sent = send_cb(cs); + gig_dbg(DEBUG_OUTPUT, "%s: send_cb -> %d", __func__, sent); + if (sent) + /* something sent or error */ + return; + + /* no command to send; get skb */ + nextskb = skb_dequeue(&bcs->squeue); + if (!nextskb) + /* no skb either, nothing to do */ + return; + bcs->tx_skb = nextskb; + + gig_dbg(DEBUG_INTR, "Dequeued skb (Adr: %lx)", + (unsigned long) bcs->tx_skb); + } + + /* send skb */ + gig_dbg(DEBUG_OUTPUT, "%s: tx_skb", __func__); + if (write_modem(cs) < 0) + gig_dbg(DEBUG_OUTPUT, "%s: write_modem failed", __func__); +} + +/* + * throw away all data queued for sending + */ +static void flush_send_queue(struct cardstate *cs) +{ + struct sk_buff *skb; + struct cmdbuf_t *cb; + unsigned long flags; + + /* command queue */ + spin_lock_irqsave(&cs->cmdlock, flags); + while ((cb = cs->cmdbuf) != NULL) { + cs->cmdbuf = cb->next; + if (cb->wake_tasklet) + tasklet_schedule(cb->wake_tasklet); + kfree(cb); + } + cs->cmdbuf = cs->lastcmdbuf = NULL; + cs->cmdbytes = cs->curlen = 0; + spin_unlock_irqrestore(&cs->cmdlock, flags); + + /* data queue */ + if (cs->bcs->tx_skb) + dev_kfree_skb_any(cs->bcs->tx_skb); + while ((skb = skb_dequeue(&cs->bcs->squeue)) != NULL) + dev_kfree_skb_any(skb); +} + + +/* Gigaset Driver Interface */ +/* ======================== */ + +/* + * queue an AT command string for transmission to the Gigaset device + * parameters: + * cs controller state structure + * buf buffer containing the string to send + * len number of characters to send + * wake_tasklet tasklet to run when transmission is complete, or NULL + * return value: + * number of bytes queued, or error code < 0 + */ +static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb) +{ + unsigned long flags; + + gigaset_dbg_buffer(cs->mstate != MS_LOCKED ? + DEBUG_TRANSCMD : DEBUG_LOCKCMD, + "CMD Transmit", cb->len, cb->buf); + + spin_lock_irqsave(&cs->cmdlock, flags); + cb->prev = cs->lastcmdbuf; + if (cs->lastcmdbuf) + cs->lastcmdbuf->next = cb; + else { + cs->cmdbuf = cb; + cs->curlen = cb->len; + } + cs->cmdbytes += cb->len; + cs->lastcmdbuf = cb; + spin_unlock_irqrestore(&cs->cmdlock, flags); + + spin_lock_irqsave(&cs->lock, flags); + if (cs->connected) + tasklet_schedule(&cs->write_tasklet); + spin_unlock_irqrestore(&cs->lock, flags); + return cb->len; +} + +/* + * tty_driver.write_room interface routine + * return number of characters the driver will accept to be written + * parameter: + * controller state structure + * return value: + * number of characters + */ +static int gigaset_write_room(struct cardstate *cs) +{ + unsigned bytes; + + bytes = cs->cmdbytes; + return bytes < IF_WRITEBUF ? IF_WRITEBUF - bytes : 0; +} + +/* + * tty_driver.chars_in_buffer interface routine + * return number of characters waiting to be sent + * parameter: + * controller state structure + * return value: + * number of characters + */ +static int gigaset_chars_in_buffer(struct cardstate *cs) +{ + return cs->cmdbytes; +} + +/* + * implementation of ioctl(GIGASET_BRKCHARS) + * parameter: + * controller state structure + * return value: + * -EINVAL (unimplemented function) + */ +static int gigaset_brkchars(struct cardstate *cs, const unsigned char buf[6]) +{ + /* not implemented */ + return -EINVAL; +} + +/* + * Open B channel + * Called by "do_action" in ev-layer.c + */ +static int gigaset_init_bchannel(struct bc_state *bcs) +{ + /* nothing to do for M10x */ + gigaset_bchannel_up(bcs); + return 0; +} + +/* + * Close B channel + * Called by "do_action" in ev-layer.c + */ +static int gigaset_close_bchannel(struct bc_state *bcs) +{ + /* nothing to do for M10x */ + gigaset_bchannel_down(bcs); + return 0; +} + +/* + * Set up B channel structure + * This is called by "gigaset_initcs" in common.c + */ +static int gigaset_initbcshw(struct bc_state *bcs) +{ + /* unused */ + bcs->hw.ser = NULL; + return 0; +} + +/* + * Free B channel structure + * Called by "gigaset_freebcs" in common.c + */ +static void gigaset_freebcshw(struct bc_state *bcs) +{ + /* unused */ +} + +/* + * Reinitialize B channel structure + * This is called by "bcs_reinit" in common.c + */ +static void gigaset_reinitbcshw(struct bc_state *bcs) +{ + /* nothing to do for M10x */ +} + +/* + * Free hardware specific device data + * This will be called by "gigaset_freecs" in common.c + */ +static void gigaset_freecshw(struct cardstate *cs) +{ + tasklet_kill(&cs->write_tasklet); + if (!cs->hw.ser) + return; + platform_device_unregister(&cs->hw.ser->dev); +} + +static void gigaset_device_release(struct device *dev) +{ + kfree(container_of(dev, struct ser_cardstate, dev.dev)); +} + +/* + * Set up hardware specific device data + * This is called by "gigaset_initcs" in common.c + */ +static int gigaset_initcshw(struct cardstate *cs) +{ + int rc; + struct ser_cardstate *scs; + + scs = kzalloc(sizeof(struct ser_cardstate), GFP_KERNEL); + if (!scs) { + pr_err("out of memory\n"); + return -ENOMEM; + } + cs->hw.ser = scs; + + cs->hw.ser->dev.name = GIGASET_MODULENAME; + cs->hw.ser->dev.id = cs->minor_index; + cs->hw.ser->dev.dev.release = gigaset_device_release; + rc = platform_device_register(&cs->hw.ser->dev); + if (rc != 0) { + pr_err("error %d registering platform device\n", rc); + kfree(cs->hw.ser); + cs->hw.ser = NULL; + return rc; + } + + tasklet_init(&cs->write_tasklet, + gigaset_modem_fill, (unsigned long) cs); + return 0; +} + +/* + * set modem control lines + * Parameters: + * card state structure + * modem control line state ([TIOCM_DTR]|[TIOCM_RTS]) + * Called by "gigaset_start" and "gigaset_enterconfigmode" in common.c + * and by "if_lock" and "if_termios" in interface.c + */ +static int gigaset_set_modem_ctrl(struct cardstate *cs, unsigned old_state, + unsigned new_state) +{ + struct tty_struct *tty = cs->hw.ser->tty; + unsigned int set, clear; + + WARN_ON(!tty || !tty->ops); + /* tiocmset is an optional tty driver method */ + if (!tty->ops->tiocmset) + return -EINVAL; + set = new_state & ~old_state; + clear = old_state & ~new_state; + if (!set && !clear) + return 0; + gig_dbg(DEBUG_IF, "tiocmset set %x clear %x", set, clear); + return tty->ops->tiocmset(tty, set, clear); +} + +static int gigaset_baud_rate(struct cardstate *cs, unsigned cflag) +{ + return -EINVAL; +} + +static int gigaset_set_line_ctrl(struct cardstate *cs, unsigned cflag) +{ + return -EINVAL; +} + +static const struct gigaset_ops ops = { + .write_cmd = gigaset_write_cmd, + .write_room = gigaset_write_room, + .chars_in_buffer = gigaset_chars_in_buffer, + .brkchars = gigaset_brkchars, + .init_bchannel = gigaset_init_bchannel, + .close_bchannel = gigaset_close_bchannel, + .initbcshw = gigaset_initbcshw, + .freebcshw = gigaset_freebcshw, + .reinitbcshw = gigaset_reinitbcshw, + .initcshw = gigaset_initcshw, + .freecshw = gigaset_freecshw, + .set_modem_ctrl = gigaset_set_modem_ctrl, + .baud_rate = gigaset_baud_rate, + .set_line_ctrl = gigaset_set_line_ctrl, + .send_skb = gigaset_m10x_send_skb, /* asyncdata.c */ + .handle_input = gigaset_m10x_input, /* asyncdata.c */ +}; + + +/* Line Discipline Interface */ +/* ========================= */ + +/* helper functions for cardstate refcounting */ +static struct cardstate *cs_get(struct tty_struct *tty) +{ + struct cardstate *cs = tty->disc_data; + + if (!cs || !cs->hw.ser) { + gig_dbg(DEBUG_ANY, "%s: no cardstate", __func__); + return NULL; + } + atomic_inc(&cs->hw.ser->refcnt); + return cs; +} + +static void cs_put(struct cardstate *cs) +{ + if (atomic_dec_and_test(&cs->hw.ser->refcnt)) + complete(&cs->hw.ser->dead_cmp); +} + +/* + * Called by the tty driver when the line discipline is pushed onto the tty. + * Called in process context. + */ +static int +gigaset_tty_open(struct tty_struct *tty) +{ + struct cardstate *cs; + int rc; + + gig_dbg(DEBUG_INIT, "Starting HLL for Gigaset M101"); + + pr_info(DRIVER_DESC "\n"); + + if (!driver) { + pr_err("%s: no driver structure\n", __func__); + return -ENODEV; + } + + /* allocate memory for our device state and initialize it */ + cs = gigaset_initcs(driver, 1, 1, 0, cidmode, GIGASET_MODULENAME); + if (!cs) { + rc = -ENODEV; + goto error; + } + + cs->dev = &cs->hw.ser->dev.dev; + cs->hw.ser->tty = tty; + atomic_set(&cs->hw.ser->refcnt, 1); + init_completion(&cs->hw.ser->dead_cmp); + tty->disc_data = cs; + + /* Set the amount of data we're willing to receive per call + * from the hardware driver to half of the input buffer size + * to leave some reserve. + * Note: We don't do flow control towards the hardware driver. + * If more data is received than will fit into the input buffer, + * it will be dropped and an error will be logged. This should + * never happen as the device is slow and the buffer size ample. + */ + tty->receive_room = RBUFSIZE/2; + + /* OK.. Initialization of the datastructures and the HW is done.. Now + * startup system and notify the LL that we are ready to run + */ + if (startmode == SM_LOCKED) + cs->mstate = MS_LOCKED; + rc = gigaset_start(cs); + if (rc < 0) { + tasklet_kill(&cs->write_tasklet); + goto error; + } + + gig_dbg(DEBUG_INIT, "Startup of HLL done"); + return 0; + +error: + gig_dbg(DEBUG_INIT, "Startup of HLL failed"); + tty->disc_data = NULL; + gigaset_freecs(cs); + return rc; +} + +/* + * Called by the tty driver when the line discipline is removed. + * Called from process context. + */ +static void +gigaset_tty_close(struct tty_struct *tty) +{ + struct cardstate *cs = tty->disc_data; + + gig_dbg(DEBUG_INIT, "Stopping HLL for Gigaset M101"); + + if (!cs) { + gig_dbg(DEBUG_INIT, "%s: no cardstate", __func__); + return; + } + + /* prevent other callers from entering ldisc methods */ + tty->disc_data = NULL; + + if (!cs->hw.ser) + pr_err("%s: no hw cardstate\n", __func__); + else { + /* wait for running methods to finish */ + if (!atomic_dec_and_test(&cs->hw.ser->refcnt)) + wait_for_completion(&cs->hw.ser->dead_cmp); + } + + /* stop operations */ + gigaset_stop(cs); + tasklet_kill(&cs->write_tasklet); + flush_send_queue(cs); + cs->dev = NULL; + gigaset_freecs(cs); + + gig_dbg(DEBUG_INIT, "Shutdown of HLL done"); +} + +/* + * Called by the tty driver when the tty line is hung up. + * Wait for I/O to driver to complete and unregister ISDN device. + * This is already done by the close routine, so just call that. + * Called from process context. + */ +static int gigaset_tty_hangup(struct tty_struct *tty) +{ + gigaset_tty_close(tty); + return 0; +} + +/* + * Ioctl on the tty. + * Called in process context only. + * May be re-entered by multiple ioctl calling threads. + */ +static int +gigaset_tty_ioctl(struct tty_struct *tty, struct file *file, + unsigned int cmd, unsigned long arg) +{ + struct cardstate *cs = cs_get(tty); + int rc, val; + int __user *p = (int __user *)arg; + + if (!cs) + return -ENXIO; + + switch (cmd) { + + case FIONREAD: + /* unused, always return zero */ + val = 0; + rc = put_user(val, p); + break; + + case TCFLSH: + /* flush our buffers and the serial port's buffer */ + switch (arg) { + case TCIFLUSH: + /* no own input buffer to flush */ + break; + case TCIOFLUSH: + case TCOFLUSH: + flush_send_queue(cs); + break; + } + /* Pass through */ + + default: + /* pass through to underlying serial device */ + rc = n_tty_ioctl_helper(tty, file, cmd, arg); + break; + } + cs_put(cs); + return rc; +} + +/* + * Called by the tty driver when a block of data has been received. + * Will not be re-entered while running but other ldisc functions + * may be called in parallel. + * Can be called from hard interrupt level as well as soft interrupt + * level or mainline. + * Parameters: + * tty tty structure + * buf buffer containing received characters + * cflags buffer containing error flags for received characters (ignored) + * count number of received characters + */ +static void +gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf, + char *cflags, int count) +{ + struct cardstate *cs = cs_get(tty); + unsigned tail, head, n; + struct inbuf_t *inbuf; + + if (!cs) + return; + inbuf = cs->inbuf; + if (!inbuf) { + dev_err(cs->dev, "%s: no inbuf\n", __func__); + cs_put(cs); + return; + } + + tail = inbuf->tail; + head = inbuf->head; + gig_dbg(DEBUG_INTR, "buffer state: %u -> %u, receive %u bytes", + head, tail, count); + + if (head <= tail) { + /* possible buffer wraparound */ + n = min_t(unsigned, count, RBUFSIZE - tail); + memcpy(inbuf->data + tail, buf, n); + tail = (tail + n) % RBUFSIZE; + buf += n; + count -= n; + } + + if (count > 0) { + /* tail < head and some data left */ + n = head - tail - 1; + if (count > n) { + dev_err(cs->dev, + "inbuf overflow, discarding %d bytes\n", + count - n); + count = n; + } + memcpy(inbuf->data + tail, buf, count); + tail += count; + } + + gig_dbg(DEBUG_INTR, "setting tail to %u", tail); + inbuf->tail = tail; + + /* Everything was received .. Push data into handler */ + gig_dbg(DEBUG_INTR, "%s-->BH", __func__); + gigaset_schedule_event(cs); + cs_put(cs); +} + +/* + * Called by the tty driver when there's room for more data to send. + */ +static void +gigaset_tty_wakeup(struct tty_struct *tty) +{ + struct cardstate *cs = cs_get(tty); + + clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + if (!cs) + return; + tasklet_schedule(&cs->write_tasklet); + cs_put(cs); +} + +static struct tty_ldisc_ops gigaset_ldisc = { + .owner = THIS_MODULE, + .magic = TTY_LDISC_MAGIC, + .name = "ser_gigaset", + .open = gigaset_tty_open, + .close = gigaset_tty_close, + .hangup = gigaset_tty_hangup, + .ioctl = gigaset_tty_ioctl, + .receive_buf = gigaset_tty_receive, + .write_wakeup = gigaset_tty_wakeup, +}; + + +/* Initialization / Shutdown */ +/* ========================= */ + +static int __init ser_gigaset_init(void) +{ + int rc; + + gig_dbg(DEBUG_INIT, "%s", __func__); + rc = platform_driver_register(&device_driver); + if (rc != 0) { + pr_err("error %d registering platform driver\n", rc); + return rc; + } + + /* allocate memory for our driver state and initialize it */ + driver = gigaset_initdriver(GIGASET_MINOR, GIGASET_MINORS, + GIGASET_MODULENAME, GIGASET_DEVNAME, + &ops, THIS_MODULE); + if (!driver) { + rc = -ENOMEM; + goto error; + } + + rc = tty_register_ldisc(N_GIGASET_M101, &gigaset_ldisc); + if (rc != 0) { + pr_err("error %d registering line discipline\n", rc); + goto error; + } + + return 0; + +error: + if (driver) { + gigaset_freedriver(driver); + driver = NULL; + } + platform_driver_unregister(&device_driver); + return rc; +} + +static void __exit ser_gigaset_exit(void) +{ + int rc; + + gig_dbg(DEBUG_INIT, "%s", __func__); + + if (driver) { + gigaset_freedriver(driver); + driver = NULL; + } + + rc = tty_unregister_ldisc(N_GIGASET_M101); + if (rc != 0) + pr_err("error %d unregistering line discipline\n", rc); + + platform_driver_unregister(&device_driver); +} + +module_init(ser_gigaset_init); +module_exit(ser_gigaset_exit); |