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path: root/drivers/tty/n_gsm.c
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Diffstat (limited to 'drivers/tty/n_gsm.c')
-rw-r--r--drivers/tty/n_gsm.c55
1 files changed, 32 insertions, 23 deletions
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 38eb49ba361f..c38f06139ccf 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -72,6 +72,8 @@ module_param(debug, int, 0600);
*/
#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)
/**
@@ -313,6 +315,7 @@ static struct tty_driver *gsm_tty_driver;
#define GSM1_ESCAPE_BITS 0x20
#define XON 0x11
#define XOFF 0x13
+#define ISO_IEC_646_MASK 0x7F
static const struct tty_port_operations gsm_port_ops;
@@ -427,7 +430,7 @@ static u8 gsm_encode_modem(const struct gsm_dlci *dlci)
modembits |= MDM_RTR;
if (dlci->modem_tx & TIOCM_RI)
modembits |= MDM_IC;
- if (dlci->modem_tx & TIOCM_CD)
+ if (dlci->modem_tx & TIOCM_CD || dlci->gsm->initiator)
modembits |= MDM_DV;
return modembits;
}
@@ -531,7 +534,8 @@ static int gsm_stuff_frame(const u8 *input, u8 *output, int len)
int olen = 0;
while (len--) {
if (*input == GSM1_SOF || *input == GSM1_ESCAPE
- || *input == XON || *input == XOFF) {
+ || (*input & ISO_IEC_646_MASK) == XON
+ || (*input & ISO_IEC_646_MASK) == XOFF) {
*output++ = GSM1_ESCAPE;
*output++ = *input++ ^ GSM1_ESCAPE_BITS;
olen++;
@@ -821,7 +825,7 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
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);
@@ -1298,11 +1302,12 @@ static void gsm_control_response(struct gsm_mux *gsm, unsigned int command,
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);
}
@@ -1325,7 +1330,6 @@ static void gsm_control_retransmit(struct timer_list *t)
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;
@@ -1334,6 +1338,7 @@ static void gsm_control_retransmit(struct timer_list *t)
wake_up(&gsm->event);
return;
}
+ gsm->cretries--;
gsm_control_transmit(gsm, ctrl);
mod_timer(&gsm->t2_timer, jiffies + gsm->t2 * HZ / 100);
}
@@ -1374,7 +1379,7 @@ retry:
/* 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;
@@ -1488,7 +1493,7 @@ static void gsm_dlci_t1(struct timer_list *t)
dlci->mode = DLCI_MODE_ADM;
gsm_dlci_open(dlci);
} else {
- gsm_dlci_close(dlci);
+ gsm_dlci_begin_close(dlci); /* prevent half open link */
}
break;
@@ -1720,7 +1725,12 @@ static void gsm_dlci_release(struct gsm_dlci *dlci)
gsm_destroy_network(dlci);
mutex_unlock(&dlci->mutex);
- tty_hangup(tty);
+ /* We cannot use tty_hangup() because in tty_kref_put() the tty
+ * driver assumes that the hangup queue is free and reuses it to
+ * queue release_one_tty() -> NULL pointer panic in
+ * process_one_work().
+ */
+ tty_vhangup(tty);
tty_port_tty_set(&dlci->port, NULL);
tty_kref_put(tty);
@@ -1803,7 +1813,6 @@ static void gsm_queue(struct gsm_mux *gsm)
gsm_response(gsm, address, UA);
gsm_dlci_close(dlci);
break;
- case UA:
case UA|PF:
if (cr == 0 || dlci == NULL)
break;
@@ -1954,7 +1963,8 @@ static void gsm1_receive(struct gsm_mux *gsm, unsigned char c)
}
/* 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
@@ -2091,6 +2101,7 @@ static void gsm_cleanup_mux(struct gsm_mux *gsm)
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);
@@ -2201,7 +2212,7 @@ static struct gsm_mux *gsm_alloc_mux(void)
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);
@@ -2257,7 +2268,7 @@ static int gsm_config(struct gsm_mux *gsm, struct gsm_config *c)
/* 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;
@@ -2872,19 +2883,17 @@ static struct tty_ldisc_ops tty_ldisc_packet = {
static int gsmtty_modem_update(struct gsm_dlci *dlci, u8 brk)
{
- u8 modembits[5];
+ u8 modembits[3];
struct gsm_control *ctrl;
int len = 2;
- if (brk)
+ modembits[0] = (dlci->addr << 2) | 2 | EA; /* DLCI, Valid, EA */
+ modembits[1] = (gsm_encode_modem(dlci) << 1) | EA;
+ if (brk) {
+ modembits[2] = (brk << 4) | 2 | EA; /* Length, Break, EA */
len++;
-
- 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);
+ }
+ ctrl = gsm_control_send(dlci->gsm, CMD_MSC, modembits, len);
if (ctrl == NULL)
return -ENOMEM;
return gsm_control_wait(dlci->gsm, ctrl);
generated by cgit v1.2.3 (git 2.0.4) at 2024-04-23 22:41:34 +0000