Commit a6b5c5dc authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'tty-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty 

Pull tty/serial fixes from Greg KH:
 "Here are some small serial driver fixes, and a larger number of GSM
  line discipline fixes for 5.18-rc5.

  These include:

   - lots of tiny n_gsm fixes for issues to resolve a number of reported
     problems. Seems that people are starting to actually use this code
     again.

   - 8250 driver fixes for some devices

   - imx serial driver fix

   - amba-pl011 driver fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (27 commits)
  tty: n_gsm: fix sometimes uninitialized warning in gsm_dlci_modem_output()
  serial: 8250: Correct the clock for EndRun PTP/1588 PCIe device
  serial: 8250: Also set sticky MCR bits in console restoration
  tty: n_gsm: fix software flow control handling
  tty: n_gsm: fix invalid use of MSC in advanced option
  tty: n_gsm: fix broken virtual tty handling
  Revert "serial: sc16is7xx: Clear RS485 bits in the shutdown"
  tty: n_gsm: fix missing update of modem controls after DLCI open
  serial: 8250: Fix runtime PM for start_tx() for empty buffer
  serial: imx: fix overrun interrupts in DMA mode
  serial: amba-pl011: do not time out prematurely when draining tx fifo
  tty: n_gsm: fix incorrect UA handling
  tty: n_gsm: fix reset fifo race condition
  tty: n_gsm: fix missing tty wakeup in convergence layer type 2
  tty: n_gsm: fix wrong signal octets encoding in MSC
  tty: n_gsm: fix wrong command frame length field encoding
  tty: n_gsm: fix wrong command retry handling
  tty: n_gsm: fix missing explicit ldisc flush
  tty: n_gsm: fix wrong DLCI release order
  tty: n_gsm: fix insufficient txframe size
  ...
parents da1b4042 19317433

drivers/tty/n_gsm.c

+276 −201
Original line number Diff line number Diff line
@@ -73,6 +73,8 @@ 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)



/*
@@ -219,7 +221,6 @@ struct gsm_mux { 
	int encoding;

	u8 control;

	u8 fcs;

	u8 received_fcs;

	u8 *txframe;			/* TX framing buffer */



	/* Method for the receiver side */
@@ -231,6 +232,7 @@ struct gsm_mux { 
	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;
@@ -271,10 +273,6 @@ static DEFINE_SPINLOCK(gsm_mux_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
@@ -369,6 +367,7 @@ static const u8 gsm_fcs8[256] = { 
#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
@@ -832,7 +831,7 @@ 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);
@@ -916,6 +915,66 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, 
	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
@@ -1093,7 +1152,6 @@ static void gsm_control_modem(struct gsm_mux *gsm, const u8 *data, int clen) 
{

	unsigned int addr = 0;

	unsigned int modem = 0;

	unsigned int brk = 0;

	struct gsm_dlci *dlci;

	int len = clen;

	int slen;
@@ -1123,17 +1181,8 @@ static void gsm_control_modem(struct gsm_mux *gsm, const u8 *data, int clen) 
			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);
@@ -1193,7 +1242,6 @@ static void gsm_control_rls(struct gsm_mux *gsm, const u8 *data, int clen) 
}



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
@@ -1212,28 +1260,15 @@ static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, 
{

	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;
@@ -1326,11 +1361,12 @@ 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);

}
@@ -1353,7 +1389,6 @@ 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;
@@ -1362,6 +1397,7 @@ 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);

	}
@@ -1402,7 +1438,7 @@ static struct gsm_control *gsm_control_send(struct gsm_mux *gsm, 


	/* 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;
@@ -1450,20 +1486,22 @@ static int gsm_control_wait(struct gsm_mux *gsm, struct gsm_control *control) 


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 */
@@ -1485,8 +1523,9 @@ static void gsm_dlci_open(struct gsm_dlci *dlci) 
	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);

}
@@ -1623,6 +1662,7 @@ static void gsm_dlci_data(struct gsm_dlci *dlci, const u8 *data, int clen) 
		tty = tty_port_tty_get(port);

		if (tty) {

			gsm_process_modem(tty, dlci, modem, slen);

			tty_wakeup(tty);

			tty_kref_put(tty);

		}

		fallthrough;
@@ -1793,19 +1833,7 @@ static void gsm_queue(struct gsm_mux *gsm) 
	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)
@@ -1836,11 +1864,6 @@ static void gsm_queue(struct gsm_mux *gsm) 
		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:
@@ -1851,35 +1874,9 @@ static void gsm_queue(struct gsm_mux *gsm) 
			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;

				}

			}

		}

		break;

	case UA:

	case UA|PF:

		if (cr == 0 || dlci == NULL)

			break;
@@ -1993,19 +1990,25 @@ static void gsm0_receive(struct gsm_mux *gsm, unsigned char c) 
		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;

		}

		if (c == GSM0_SOF)

			gsm_queue(gsm);

		else

			gsm->bad_size++;

		break;

	default:

		pr_debug("%s: unhandled state: %d\n", __func__, gsm->state);
@@ -2023,12 +2026,35 @@ static void gsm0_receive(struct gsm_mux *gsm, unsigned char c) 


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);
@@ -2037,6 +2063,7 @@ 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) {

			if (gsm->state != GSM_SEARCH)

				gsm->malformed++;

			gsm->state = GSM_START;

		}
@@ -2106,74 +2133,43 @@ static void gsm_error(struct gsm_mux *gsm) 
	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);
@@ -2191,7 +2187,6 @@ static void gsm_cleanup_mux(struct gsm_mux *gsm) 
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);
@@ -2203,18 +2198,6 @@ static int gsm_activate_mux(struct gsm_mux *gsm) 
	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;
@@ -2230,6 +2213,15 @@ static int gsm_activate_mux(struct gsm_mux *gsm) 
 */

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);
@@ -2249,12 +2241,20 @@ static void gsm_free_muxr(struct kref *ref) 


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)
@@ -2275,6 +2275,7 @@ static inline unsigned int mux_line_to_num(unsigned int line) 


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;
@@ -2283,7 +2284,7 @@ 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);
@@ -2304,6 +2305,26 @@ static struct gsm_mux *gsm_alloc_mux(void) 
	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;

}
@@ -2339,7 +2360,7 @@ 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;
@@ -2370,19 +2391,11 @@ static int gsm_config(struct gsm_mux *gsm, struct gsm_config *c) 


	/*

	 * 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;
@@ -2450,13 +2463,15 @@ static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) 
	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;
@@ -2471,7 +2486,6 @@ static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) 
			}

		}

	}

	}

	return ret;

}
@@ -2490,11 +2504,10 @@ static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) 
	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);

	/* Restore tty XON/XOFF handling. */

	gsm->tty->termios.c_iflag = gsm->old_c_iflag;

	tty_kref_put(gsm->tty);

	gsm->tty = NULL;

}
@@ -2559,6 +2572,12 @@ static void gsmld_close(struct tty_struct *tty) 
{

	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);
@@ -2597,7 +2616,7 @@ static int gsmld_open(struct tty_struct *tty) 


	ret = gsmld_attach_gsm(tty, gsm);

	if (ret != 0) {

		gsm_cleanup_mux(gsm);

		gsm_cleanup_mux(gsm, false);

		mux_put(gsm);

	}

	return ret;
@@ -2954,26 +2973,78 @@ static struct tty_ldisc_ops tty_ldisc_packet = { 


#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)

{

	u8 modembits[5];

	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[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);
@@ -3006,7 +3077,7 @@ static void gsm_dtr_rts(struct tty_port *port, int onoff) 
		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);

	}

}
@@ -3155,13 +3226,17 @@ static unsigned int gsmtty_chars_in_buffer(struct tty_struct *tty) 
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 */

}
@@ -3193,7 +3268,7 @@ static int gsmtty_tiocmset(struct tty_struct *tty, 


	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;

}
@@ -3254,7 +3329,7 @@ static void gsmtty_throttle(struct tty_struct *tty) 
		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)
@@ -3266,7 +3341,7 @@ 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)
@@ -3284,7 +3359,7 @@ 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)

drivers/tty/serial/8250/8250_pci.c

+4 −4
Original line number Diff line number Diff line
@@ -2667,7 +2667,7 @@ enum pci_board_num_t { 
	pbn_panacom2,

	pbn_panacom4,

	pbn_plx_romulus,

	pbn_endrun_2_4000000,

	pbn_endrun_2_3906250,

	pbn_oxsemi,

	pbn_oxsemi_1_3906250,

	pbn_oxsemi_2_3906250,
@@ -3195,10 +3195,10 @@ static struct pciserial_board pci_boards[] = { 
	* signal now many ports are available

	* 2 port 952 Uart support

	*/

	[pbn_endrun_2_4000000] = {

	[pbn_endrun_2_3906250] = {

		.flags		= FL_BASE0,

		.num_ports	= 2,

		.base_baud	= 4000000,

		.base_baud	= 3906250,

		.uart_offset	= 0x200,

		.first_offset	= 0x1000,

	},
@@ -4115,7 +4115,7 @@ static const struct pci_device_id serial_pci_tbl[] = { 
	*/

	{	PCI_VENDOR_ID_ENDRUN, PCI_DEVICE_ID_ENDRUN_1588,

		PCI_ANY_ID, PCI_ANY_ID, 0, 0,

		pbn_endrun_2_4000000 },

		pbn_endrun_2_3906250 },

	/*

	 * Quatech cards. These actually have configurable clocks but for

	 * now we just use the default.

drivers/tty/serial/8250/8250_port.c

+3 −3
Original line number Diff line number Diff line
@@ -1675,11 +1675,11 @@ static void serial8250_start_tx(struct uart_port *port) 
	struct uart_8250_port *up = up_to_u8250p(port);

	struct uart_8250_em485 *em485 = up->em485;



	serial8250_rpm_get_tx(up);



	if (!port->x_char && uart_circ_empty(&port->state->xmit))

		return;



	serial8250_rpm_get_tx(up);



	if (em485 &&

	    em485->active_timer == &em485->start_tx_timer)

		return;
@@ -3329,7 +3329,7 @@ static void serial8250_console_restore(struct uart_8250_port *up) 


	serial8250_set_divisor(port, baud, quot, frac);

	serial_port_out(port, UART_LCR, up->lcr);

	serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);

	serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS);

}



/*

drivers/tty/serial/amba-pl011.c

+7 −2
Original line number Diff line number Diff line
@@ -1255,13 +1255,18 @@ static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) 


static void pl011_rs485_tx_stop(struct uart_amba_port *uap)

{

	/*

	 * To be on the safe side only time out after twice as many iterations

	 * as fifo size.

	 */

	const int MAX_TX_DRAIN_ITERS = uap->port.fifosize * 2;

	struct uart_port *port = &uap->port;

	int i = 0;

	u32 cr;



	/* Wait until hardware tx queue is empty */

	while (!pl011_tx_empty(port)) {

		if (i == port->fifosize) {

		if (i > MAX_TX_DRAIN_ITERS) {

			dev_warn(port->dev,

				 "timeout while draining hardware tx queue\n");

			break;
@@ -2052,7 +2057,7 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios, 
	 * with the given baud rate. We use this as the poll interval when we

	 * wait for the tx queue to empty.

	 */

	uap->rs485_tx_drain_interval = (bits * 1000 * 1000) / baud;

	uap->rs485_tx_drain_interval = DIV_ROUND_UP(bits * 1000 * 1000, baud);



	pl011_setup_status_masks(port, termios);

drivers/tty/serial/imx.c

+1 −1
Original line number Diff line number Diff line
@@ -1448,7 +1448,7 @@ static int imx_uart_startup(struct uart_port *port) 
	imx_uart_writel(sport, ucr1, UCR1);



	ucr4 = imx_uart_readl(sport, UCR4) & ~(UCR4_OREN | UCR4_INVR);

	if (!sport->dma_is_enabled)

	if (!dma_is_inited)

		ucr4 |= UCR4_OREN;

	if (sport->inverted_rx)

		ucr4 |= UCR4_INVR;