*/
#define MAX_MRU 1500
#define MAX_MTU 1500
+/* SOF, ADDR, CTRL, LEN1, LEN2, ..., FCS, EOF */
+#define PROT_OVERHEAD 7
#define GSM_NET_TX_TIMEOUT (HZ*10)
/*
int encoding;
u8 control;
u8 fcs;
- u8 received_fcs;
u8 *txframe; /* TX framing buffer */
/* Method for the receiver side */
int initiator; /* Did we initiate connection */
bool dead; /* Has the mux been shut down */
struct gsm_dlci *dlci[NUM_DLCI];
+ int old_c_iflag; /* termios c_iflag value before attach */
bool constipated; /* Asked by remote to shut up */
spinlock_t tx_lock;
static struct tty_driver *gsm_tty_driver;
-/* Save dlci open address */
-static int addr_open[256] = { 0 };
-/* Save dlci open count */
-static int addr_cnt;
/*
* This section of the driver logic implements the GSM encodings
* both the basic and the 'advanced'. Reliable transport is not
#define GOOD_FCS 0xCF
static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len);
+static int gsm_modem_update(struct gsm_dlci *dlci, u8 brk);
/**
* gsm_fcs_add - update FCS
*--dp = msg->ctrl;
if (gsm->initiator)
- *--dp = (msg->addr << 2) | 2 | EA;
+ *--dp = (msg->addr << 2) | CR | EA;
else
*--dp = (msg->addr << 2) | EA;
*fcs = gsm_fcs_add_block(INIT_FCS, dp , msg->data - dp);
break;
case 2: /* Unstructed with modem bits.
Always one byte as we never send inline break data */
- *dp++ = gsm_encode_modem(dlci);
+ *dp++ = (gsm_encode_modem(dlci) << 1) | EA;
break;
}
WARN_ON(kfifo_out_locked(&dlci->fifo, dp , len, &dlci->lock) != len);
return size;
}
+/**
+ * gsm_dlci_modem_output - try and push modem status out of a DLCI
+ * @gsm: mux
+ * @dlci: the DLCI to pull modem status from
+ * @brk: break signal
+ *
+ * Push an empty frame in to the transmit queue to update the modem status
+ * bits and to transmit an optional break.
+ *
+ * Caller must hold the tx_lock of the mux.
+ */
+
+static int gsm_dlci_modem_output(struct gsm_mux *gsm, struct gsm_dlci *dlci,
+ u8 brk)
+{
+ u8 *dp = NULL;
+ struct gsm_msg *msg;
+ int size = 0;
+
+ /* for modem bits without break data */
+ switch (dlci->adaption) {
+ case 1: /* Unstructured */
+ break;
+ case 2: /* Unstructured with modem bits. */
+ size++;
+ if (brk > 0)
+ size++;
+ break;
+ default:
+ pr_err("%s: unsupported adaption %d\n", __func__,
+ dlci->adaption);
+ return -EINVAL;
+ }
+
+ msg = gsm_data_alloc(gsm, dlci->addr, size, gsm->ftype);
+ if (!msg) {
+ pr_err("%s: gsm_data_alloc error", __func__);
+ return -ENOMEM;
+ }
+ dp = msg->data;
+ switch (dlci->adaption) {
+ case 1: /* Unstructured */
+ break;
+ case 2: /* Unstructured with modem bits. */
+ if (brk == 0) {
+ *dp++ = (gsm_encode_modem(dlci) << 1) | EA;
+ } else {
+ *dp++ = gsm_encode_modem(dlci) << 1;
+ *dp++ = (brk << 4) | 2 | EA; /* Length, Break, EA */
+ }
+ break;
+ default:
+ /* Handled above */
+ break;
+ }
+
+ __gsm_data_queue(dlci, msg);
+ return size;
+}
+
/**
* gsm_dlci_data_sweep - look for data to send
* @gsm: the GSM mux
{
unsigned int addr = 0;
unsigned int modem = 0;
- unsigned int brk = 0;
struct gsm_dlci *dlci;
int len = clen;
int slen;
return;
}
len--;
- if (len > 0) {
- while (gsm_read_ea(&brk, *dp++) == 0) {
- len--;
- if (len == 0)
- return;
- }
- modem <<= 7;
- modem |= (brk & 0x7f);
- }
tty = tty_port_tty_get(&dlci->port);
- gsm_process_modem(tty, dlci, modem, slen);
+ gsm_process_modem(tty, dlci, modem, slen - len);
if (tty) {
tty_wakeup(tty);
tty_kref_put(tty);
}
static void gsm_dlci_begin_close(struct gsm_dlci *dlci);
-static void gsm_dlci_close(struct gsm_dlci *dlci);
/**
* gsm_control_message - DLCI 0 control processing
{
u8 buf[1];
unsigned long flags;
- struct gsm_dlci *dlci;
- int i;
- int address;
switch (command) {
case CMD_CLD: {
- if (addr_cnt > 0) {
- for (i = 0; i < addr_cnt; i++) {
- address = addr_open[i];
- dlci = gsm->dlci[address];
- gsm_dlci_close(dlci);
- addr_open[i] = 0;
- }
- }
+ struct gsm_dlci *dlci = gsm->dlci[0];
/* Modem wishes to close down */
- dlci = gsm->dlci[0];
if (dlci) {
dlci->dead = true;
gsm->dead = true;
- gsm_dlci_close(dlci);
- addr_cnt = 0;
- gsm_response(gsm, 0, UA|PF);
+ gsm_dlci_begin_close(dlci);
}
}
break;
static void gsm_control_transmit(struct gsm_mux *gsm, struct gsm_control *ctrl)
{
- struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 1, gsm->ftype);
+ struct gsm_msg *msg = gsm_data_alloc(gsm, 0, ctrl->len + 2, gsm->ftype);
if (msg == NULL)
return;
- msg->data[0] = (ctrl->cmd << 1) | 2 | EA; /* command */
- memcpy(msg->data + 1, ctrl->data, ctrl->len);
+ msg->data[0] = (ctrl->cmd << 1) | CR | EA; /* command */
+ msg->data[1] = (ctrl->len << 1) | EA;
+ memcpy(msg->data + 2, ctrl->data, ctrl->len);
gsm_data_queue(gsm->dlci[0], msg);
}
spin_lock_irqsave(&gsm->control_lock, flags);
ctrl = gsm->pending_cmd;
if (ctrl) {
- gsm->cretries--;
if (gsm->cretries == 0) {
gsm->pending_cmd = NULL;
ctrl->error = -ETIMEDOUT;
wake_up(&gsm->event);
return;
}
+ gsm->cretries--;
gsm_control_transmit(gsm, ctrl);
mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100);
}
/* If DLCI0 is in ADM mode skip retries, it won't respond */
if (gsm->dlci[0]->mode == DLCI_MODE_ADM)
- gsm->cretries = 1;
+ gsm->cretries = 0;
else
gsm->cretries = gsm->n2;
static void gsm_dlci_close(struct gsm_dlci *dlci)
{
+ unsigned long flags;
+
del_timer(&dlci->t1);
if (debug & 8)
pr_debug("DLCI %d goes closed.\n", dlci->addr);
dlci->state = DLCI_CLOSED;
if (dlci->addr != 0) {
tty_port_tty_hangup(&dlci->port, false);
+ spin_lock_irqsave(&dlci->lock, flags);
kfifo_reset(&dlci->fifo);
+ spin_unlock_irqrestore(&dlci->lock, flags);
/* Ensure that gsmtty_open() can return. */
tty_port_set_initialized(&dlci->port, 0);
wake_up_interruptible(&dlci->port.open_wait);
} else
dlci->gsm->dead = true;
- /* Unregister gsmtty driver,report gsmtty dev remove uevent for user */
- tty_unregister_device(gsm_tty_driver, dlci->addr);
wake_up(&dlci->gsm->event);
/* A DLCI 0 close is a MUX termination so we need to kick that
back to userspace somehow */
dlci->state = DLCI_OPEN;
if (debug & 8)
pr_debug("DLCI %d goes open.\n", dlci->addr);
- /* Register gsmtty driver,report gsmtty dev add uevent for user */
- tty_register_device(gsm_tty_driver, dlci->addr, NULL);
+ /* Send current modem state */
+ if (dlci->addr)
+ gsm_modem_update(dlci, 0);
wake_up(&dlci->gsm->event);
}
tty = tty_port_tty_get(port);
if (tty) {
gsm_process_modem(tty, dlci, modem, slen);
+ tty_wakeup(tty);
tty_kref_put(tty);
}
fallthrough;
struct gsm_dlci *dlci;
u8 cr;
int address;
- int i, j, k, address_tmp;
- /* We have to sneak a look at the packet body to do the FCS.
- A somewhat layering violation in the spec */
- if ((gsm->control & ~PF) == UI)
- gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len);
- if (gsm->encoding == 0) {
- /* WARNING: gsm->received_fcs is used for
- gsm->encoding = 0 only.
- In this case it contain the last piece of data
- required to generate final CRC */
- gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs);
- }
if (gsm->fcs != GOOD_FCS) {
gsm->bad_fcs++;
if (debug & 4)
else {
gsm_response(gsm, address, UA|PF);
gsm_dlci_open(dlci);
- /* Save dlci open address */
- if (address) {
- addr_open[addr_cnt] = address;
- addr_cnt++;
- }
}
break;
case DISC|PF:
return;
}
/* Real close complete */
- if (!address) {
- if (addr_cnt > 0) {
- for (i = 0; i < addr_cnt; i++) {
- address = addr_open[i];
- dlci = gsm->dlci[address];
- gsm_dlci_close(dlci);
- addr_open[i] = 0;
- }
- }
- dlci = gsm->dlci[0];
- gsm_dlci_close(dlci);
- addr_cnt = 0;
- gsm_response(gsm, 0, UA|PF);
- } else {
- gsm_response(gsm, address, UA|PF);
- gsm_dlci_close(dlci);
- /* clear dlci address */
- for (j = 0; j < addr_cnt; j++) {
- address_tmp = addr_open[j];
- if (address_tmp == address) {
- for (k = j; k < addr_cnt; k++)
- addr_open[k] = addr_open[k+1];
- addr_cnt--;
- break;
- }
- }
- }
+ gsm_response(gsm, address, UA|PF);
+ gsm_dlci_close(dlci);
break;
- case UA:
case UA|PF:
if (cr == 0 || dlci == NULL)
break;
case UI|PF:
case UIH:
case UIH|PF:
-#if 0
- if (cr)
- goto invalid;
-#endif
if (dlci == NULL || dlci->state != DLCI_OPEN) {
gsm_command(gsm, address, DM|PF);
return;
break;
case GSM_DATA: /* Data */
gsm->buf[gsm->count++] = c;
- if (gsm->count == gsm->len)
+ if (gsm->count == gsm->len) {
+ /* Calculate final FCS for UI frames over all data */
+ if ((gsm->control & ~PF) != UIH) {
+ gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf,
+ gsm->count);
+ }
gsm->state = GSM_FCS;
+ }
break;
case GSM_FCS: /* FCS follows the packet */
- gsm->received_fcs = c;
- gsm_queue(gsm);
+ gsm->fcs = gsm_fcs_add(gsm->fcs, c);
gsm->state = GSM_SSOF;
break;
case GSM_SSOF:
- if (c == GSM0_SOF) {
- gsm->state = GSM_SEARCH;
- break;
- }
+ gsm->state = GSM_SEARCH;
+ if (c == GSM0_SOF)
+ gsm_queue(gsm);
+ else
+ gsm->bad_size++;
break;
default:
pr_debug("%s: unhandled state: %d\n", __func__, gsm->state);
static void gsm1_receive(struct gsm_mux *gsm, unsigned char c)
{
+ /* handle XON/XOFF */
+ if ((c & ISO_IEC_646_MASK) == XON) {
+ gsm->constipated = true;
+ return;
+ } else if ((c & ISO_IEC_646_MASK) == XOFF) {
+ gsm->constipated = false;
+ /* Kick the link in case it is idling */
+ gsm_data_kick(gsm, NULL);
+ return;
+ }
if (c == GSM1_SOF) {
- /* EOF is only valid in frame if we have got to the data state
- and received at least one byte (the FCS) */
- if (gsm->state == GSM_DATA && gsm->count) {
- /* Extract the FCS */
+ /* EOF is only valid in frame if we have got to the data state */
+ if (gsm->state == GSM_DATA) {
+ if (gsm->count < 1) {
+ /* Missing FSC */
+ gsm->malformed++;
+ gsm->state = GSM_START;
+ return;
+ }
+ /* Remove the FCS from data */
gsm->count--;
+ if ((gsm->control & ~PF) != UIH) {
+ /* Calculate final FCS for UI frames over all
+ * data but FCS
+ */
+ gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf,
+ gsm->count);
+ }
+ /* Add the FCS itself to test against GOOD_FCS */
gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->buf[gsm->count]);
gsm->len = gsm->count;
gsm_queue(gsm);
}
/* Any partial frame was a runt so go back to start */
if (gsm->state != GSM_START) {
- gsm->malformed++;
+ if (gsm->state != GSM_SEARCH)
+ gsm->malformed++;
gsm->state = GSM_START;
}
/* A SOF in GSM_START means we are still reading idling or
gsm->io_error++;
}
-static int gsm_disconnect(struct gsm_mux *gsm)
-{
- struct gsm_dlci *dlci = gsm->dlci[0];
- struct gsm_control *gc;
-
- if (!dlci)
- return 0;
-
- /* In theory disconnecting DLCI 0 is sufficient but for some
- modems this is apparently not the case. */
- gc = gsm_control_send(gsm, CMD_CLD, NULL, 0);
- if (gc)
- gsm_control_wait(gsm, gc);
-
- del_timer_sync(&gsm->t2_timer);
- /* Now we are sure T2 has stopped */
-
- gsm_dlci_begin_close(dlci);
- wait_event_interruptible(gsm->event,
- dlci->state == DLCI_CLOSED);
-
- if (signal_pending(current))
- return -EINTR;
-
- return 0;
-}
-
/**
* gsm_cleanup_mux - generic GSM protocol cleanup
* @gsm: our mux
+ * @disc: disconnect link?
*
* Clean up the bits of the mux which are the same for all framing
* protocols. Remove the mux from the mux table, stop all the timers
* and then shut down each device hanging up the channels as we go.
*/
-static void gsm_cleanup_mux(struct gsm_mux *gsm)
+static void gsm_cleanup_mux(struct gsm_mux *gsm, bool disc)
{
int i;
struct gsm_dlci *dlci = gsm->dlci[0];
struct gsm_msg *txq, *ntxq;
gsm->dead = true;
+ mutex_lock(&gsm->mutex);
- spin_lock(&gsm_mux_lock);
- for (i = 0; i < MAX_MUX; i++) {
- if (gsm_mux[i] == gsm) {
- gsm_mux[i] = NULL;
- break;
+ if (dlci) {
+ if (disc && dlci->state != DLCI_CLOSED) {
+ gsm_dlci_begin_close(dlci);
+ wait_event(gsm->event, dlci->state == DLCI_CLOSED);
}
+ dlci->dead = true;
}
- spin_unlock(&gsm_mux_lock);
- /* open failed before registering => nothing to do */
- if (i == MAX_MUX)
- return;
+ /* Finish outstanding timers, making sure they are done */
del_timer_sync(&gsm->t2_timer);
- /* Now we are sure T2 has stopped */
- if (dlci)
- dlci->dead = true;
- /* Free up any link layer users */
- mutex_lock(&gsm->mutex);
- for (i = 0; i < NUM_DLCI; i++)
+ /* Free up any link layer users and finally the control channel */
+ for (i = NUM_DLCI - 1; i >= 0; i--)
if (gsm->dlci[i])
gsm_dlci_release(gsm->dlci[i]);
mutex_unlock(&gsm->mutex);
/* Now wipe the queues */
+ tty_ldisc_flush(gsm->tty);
list_for_each_entry_safe(txq, ntxq, &gsm->tx_list, list)
kfree(txq);
INIT_LIST_HEAD(&gsm->tx_list);
static int gsm_activate_mux(struct gsm_mux *gsm)
{
struct gsm_dlci *dlci;
- int i = 0;
timer_setup(&gsm->t2_timer, gsm_control_retransmit, 0);
init_waitqueue_head(&gsm->event);
else
gsm->receive = gsm1_receive;
- spin_lock(&gsm_mux_lock);
- for (i = 0; i < MAX_MUX; i++) {
- if (gsm_mux[i] == NULL) {
- gsm->num = i;
- gsm_mux[i] = gsm;
- break;
- }
- }
- spin_unlock(&gsm_mux_lock);
- if (i == MAX_MUX)
- return -EBUSY;
-
dlci = gsm_dlci_alloc(gsm, 0);
if (dlci == NULL)
return -ENOMEM;
*/
static void gsm_free_mux(struct gsm_mux *gsm)
{
+ int i;
+
+ for (i = 0; i < MAX_MUX; i++) {
+ if (gsm == gsm_mux[i]) {
+ gsm_mux[i] = NULL;
+ break;
+ }
+ }
+ mutex_destroy(&gsm->mutex);
kfree(gsm->txframe);
kfree(gsm->buf);
kfree(gsm);
static inline void mux_get(struct gsm_mux *gsm)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&gsm_mux_lock, flags);
kref_get(&gsm->ref);
+ spin_unlock_irqrestore(&gsm_mux_lock, flags);
}
static inline void mux_put(struct gsm_mux *gsm)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&gsm_mux_lock, flags);
kref_put(&gsm->ref, gsm_free_muxr);
+ spin_unlock_irqrestore(&gsm_mux_lock, flags);
}
static inline unsigned int mux_num_to_base(struct gsm_mux *gsm)
static struct gsm_mux *gsm_alloc_mux(void)
{
+ int i;
struct gsm_mux *gsm = kzalloc(sizeof(struct gsm_mux), GFP_KERNEL);
if (gsm == NULL)
return NULL;
kfree(gsm);
return NULL;
}
- gsm->txframe = kmalloc(2 * MAX_MRU + 2, GFP_KERNEL);
+ gsm->txframe = kmalloc(2 * (MAX_MTU + PROT_OVERHEAD - 1), GFP_KERNEL);
if (gsm->txframe == NULL) {
kfree(gsm->buf);
kfree(gsm);
gsm->mtu = 64;
gsm->dead = true; /* Avoid early tty opens */
+ /* Store the instance to the mux array or abort if no space is
+ * available.
+ */
+ spin_lock(&gsm_mux_lock);
+ for (i = 0; i < MAX_MUX; i++) {
+ if (!gsm_mux[i]) {
+ gsm_mux[i] = gsm;
+ gsm->num = i;
+ break;
+ }
+ }
+ spin_unlock(&gsm_mux_lock);
+ if (i == MAX_MUX) {
+ mutex_destroy(&gsm->mutex);
+ kfree(gsm->txframe);
+ kfree(gsm->buf);
+ kfree(gsm);
+ return NULL;
+ }
+
return gsm;
}
/* Check the MRU/MTU range looks sane */
if (c->mru > MAX_MRU || c->mtu > MAX_MTU || c->mru < 8 || c->mtu < 8)
return -EINVAL;
- if (c->n2 < 3)
+ if (c->n2 > 255)
return -EINVAL;
if (c->encapsulation > 1) /* Basic, advanced, no I */
return -EINVAL;
/*
* Close down what is needed, restart and initiate the new
- * configuration
+ * configuration. On the first time there is no DLCI[0]
+ * and closing or cleaning up is not necessary.
*/
-
- if (gsm->initiator && (need_close || need_restart)) {
- int ret;
-
- ret = gsm_disconnect(gsm);
-
- if (ret)
- return ret;
- }
- if (need_restart)
- gsm_cleanup_mux(gsm);
+ if (need_close || need_restart)
+ gsm_cleanup_mux(gsm, true);
gsm->initiator = c->initiator;
gsm->mru = c->mru;
int ret, i;
gsm->tty = tty_kref_get(tty);
+ /* Turn off tty XON/XOFF handling to handle it explicitly. */
+ gsm->old_c_iflag = tty->termios.c_iflag;
+ tty->termios.c_iflag &= (IXON | IXOFF);
ret = gsm_activate_mux(gsm);
if (ret != 0)
tty_kref_put(gsm->tty);
else {
/* Don't register device 0 - this is the control channel and not
a usable tty interface */
- if (gsm->initiator) {
- base = mux_num_to_base(gsm); /* Base for this MUX */
- for (i = 1; i < NUM_DLCI; i++) {
- struct device *dev;
+ base = mux_num_to_base(gsm); /* Base for this MUX */
+ for (i = 1; i < NUM_DLCI; i++) {
+ struct device *dev;
- dev = tty_register_device(gsm_tty_driver,
+ dev = tty_register_device(gsm_tty_driver,
base + i, NULL);
- if (IS_ERR(dev)) {
- for (i--; i >= 1; i--)
- tty_unregister_device(gsm_tty_driver,
- base + i);
- return PTR_ERR(dev);
- }
+ if (IS_ERR(dev)) {
+ for (i--; i >= 1; i--)
+ tty_unregister_device(gsm_tty_driver,
+ base + i);
+ return PTR_ERR(dev);
}
}
}
int i;
WARN_ON(tty != gsm->tty);
- if (gsm->initiator) {
- for (i = 1; i < NUM_DLCI; i++)
- tty_unregister_device(gsm_tty_driver, base + i);
- }
- gsm_cleanup_mux(gsm);
+ for (i = 1; i < NUM_DLCI; i++)
+ tty_unregister_device(gsm_tty_driver, base + i);
+ /* Restore tty XON/XOFF handling. */
+ gsm->tty->termios.c_iflag = gsm->old_c_iflag;
tty_kref_put(gsm->tty);
gsm->tty = NULL;
}
{
struct gsm_mux *gsm = tty->disc_data;
+ /* The ldisc locks and closes the port before calling our close. This
+ * means we have no way to do a proper disconnect. We will not bother
+ * to do one.
+ */
+ gsm_cleanup_mux(gsm, false);
+
gsmld_detach_gsm(tty, gsm);
gsmld_flush_buffer(tty);
ret = gsmld_attach_gsm(tty, gsm);
if (ret != 0) {
- gsm_cleanup_mux(gsm);
+ gsm_cleanup_mux(gsm, false);
mux_put(gsm);
}
return ret;
#define TX_SIZE 512
-static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk)
+/**
+ * gsm_modem_upd_via_data - send modem bits via convergence layer
+ * @dlci: channel
+ * @brk: break signal
+ *
+ * Send an empty frame to signal mobile state changes and to transmit the
+ * break signal for adaption 2.
+ */
+
+static void gsm_modem_upd_via_data(struct gsm_dlci *dlci, u8 brk)
+{
+ struct gsm_mux *gsm = dlci->gsm;
+ unsigned long flags;
+
+ if (dlci->state != DLCI_OPEN || dlci->adaption != 2)
+ return;
+
+ spin_lock_irqsave(&gsm->tx_lock, flags);
+ gsm_dlci_modem_output(gsm, dlci, brk);
+ spin_unlock_irqrestore(&gsm->tx_lock, flags);
+}
+
+/**
+ * gsm_modem_upd_via_msc - send modem bits via control frame
+ * @dlci: channel
+ * @brk: break signal
+ */
+
+static int gsm_modem_upd_via_msc(struct gsm_dlci *dlci, u8 brk)
{
- u8 modembits[5];
+ u8 modembits[3];
struct gsm_control *ctrl;
int len = 2;
- if (brk)
- len++;
+ if (dlci->gsm->encoding != 0)
+ return 0;
- modembits[0] = len << 1 | EA; /* Data bytes */
- modembits[1] = dlci->addr << 2 | 3; /* DLCI, EA, 1 */
- modembits[2] = gsm_encode_modem(dlci) << 1 | EA;
- if (brk)
- modembits[3] = brk << 4 | 2 | EA; /* Valid, EA */
- ctrl = gsm_control_send(dlci->gsm, CMD_MSC, modembits, len + 1);
+ modembits[0] = (dlci->addr << 2) | 2 | EA; /* DLCI, Valid, EA */
+ if (!brk) {
+ modembits[1] = (gsm_encode_modem(dlci) << 1) | EA;
+ } else {
+ modembits[1] = gsm_encode_modem(dlci) << 1;
+ modembits[2] = (brk << 4) | 2 | EA; /* Length, Break, EA */
+ len++;
+ }
+ ctrl = gsm_control_send(dlci->gsm, CMD_MSC, modembits, len);
if (ctrl == NULL)
return -ENOMEM;
return gsm_control_wait(dlci->gsm, ctrl);
}
+/**
+ * gsm_modem_update - send modem status line state
+ * @dlci: channel
+ * @brk: break signal
+ */
+
+static int gsm_modem_update(struct gsm_dlci *dlci, u8 brk)
+{
+ if (dlci->adaption == 2) {
+ /* Send convergence layer type 2 empty data frame. */
+ gsm_modem_upd_via_data(dlci, brk);
+ return 0;
+ } else if (dlci->gsm->encoding == 0) {
+ /* Send as MSC control message. */
+ return gsm_modem_upd_via_msc(dlci, brk);
+ }
+
+ /* Modem status lines are not supported. */
+ return -EPROTONOSUPPORT;
+}
+
static int gsm_carrier_raised(struct tty_port *port)
{
struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port);
modem_tx &= ~(TIOCM_DTR | TIOCM_RTS);
if (modem_tx != dlci->modem_tx) {
dlci->modem_tx = modem_tx;
- gsmtty_modem_update(dlci, 0);
+ gsm_modem_update(dlci, 0);
}
}
static void gsmtty_flush_buffer(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
+ unsigned long flags;
+
if (dlci->state == DLCI_CLOSED)
return;
/* Caution needed: If we implement reliable transport classes
then the data being transmitted can't simply be junked once
it has first hit the stack. Until then we can just blow it
away */
+ spin_lock_irqsave(&dlci->lock, flags);
kfifo_reset(&dlci->fifo);
+ spin_unlock_irqrestore(&dlci->lock, flags);
/* Need to unhook this DLCI from the transmit queue logic */
}
if (modem_tx != dlci->modem_tx) {
dlci->modem_tx = modem_tx;
- return gsmtty_modem_update(dlci, 0);
+ return gsm_modem_update(dlci, 0);
}
return 0;
}
dlci->modem_tx &= ~TIOCM_RTS;
dlci->throttled = true;
/* Send an MSC with RTS cleared */
- gsmtty_modem_update(dlci, 0);
+ gsm_modem_update(dlci, 0);
}
static void gsmtty_unthrottle(struct tty_struct *tty)
dlci->modem_tx |= TIOCM_RTS;
dlci->throttled = false;
/* Send an MSC with RTS set */
- gsmtty_modem_update(dlci, 0);
+ gsm_modem_update(dlci, 0);
}
static int gsmtty_break_ctl(struct tty_struct *tty, int state)
if (encode > 0x0F)
encode = 0x0F; /* Best effort */
}
- return gsmtty_modem_update(dlci, encode);
+ return gsm_modem_update(dlci, encode);
}
static void gsmtty_cleanup(struct tty_struct *tty)
projects / linux-2.6-microblaze.git / blobdiff