2 * Driver core for serial ports
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
6 * Copyright 1999 ARM Limited
7 * Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #include <linux/module.h>
24 #include <linux/tty.h>
25 #include <linux/tty_flip.h>
26 #include <linux/slab.h>
27 #include <linux/init.h>
28 #include <linux/console.h>
29 #include <linux/proc_fs.h>
30 #include <linux/seq_file.h>
31 #include <linux/device.h>
32 #include <linux/serial.h> /* for serial_state and serial_icounter_struct */
33 #include <linux/serial_core.h>
34 #include <linux/delay.h>
35 #include <linux/mutex.h>
38 #include <asm/uaccess.h>
41 * This is used to lock changes in serial line configuration.
43 static DEFINE_MUTEX(port_mutex
);
46 * lockdep: port->lock is initialized in two places, but we
47 * want only one lock-class:
49 static struct lock_class_key port_lock_key
;
51 #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
53 static void uart_change_speed(struct tty_struct
*tty
, struct uart_state
*state
,
54 struct ktermios
*old_termios
);
55 static void uart_wait_until_sent(struct tty_struct
*tty
, int timeout
);
56 static void uart_change_pm(struct uart_state
*state
,
57 enum uart_pm_state pm_state
);
59 static void uart_port_shutdown(struct tty_port
*port
);
62 * This routine is used by the interrupt handler to schedule processing in
63 * the software interrupt portion of the driver.
65 void uart_write_wakeup(struct uart_port
*port
)
67 struct uart_state
*state
= port
->state
;
69 * This means you called this function _after_ the port was
70 * closed. No cookie for you.
73 tty_wakeup(state
->port
.tty
);
76 static void uart_stop(struct tty_struct
*tty
)
78 struct uart_state
*state
= tty
->driver_data
;
79 struct uart_port
*port
= state
->uart_port
;
82 spin_lock_irqsave(&port
->lock
, flags
);
83 port
->ops
->stop_tx(port
);
84 spin_unlock_irqrestore(&port
->lock
, flags
);
87 static void __uart_start(struct tty_struct
*tty
)
89 struct uart_state
*state
= tty
->driver_data
;
90 struct uart_port
*port
= state
->uart_port
;
92 if (!tty
->stopped
&& !tty
->hw_stopped
)
93 port
->ops
->start_tx(port
);
96 static void uart_start(struct tty_struct
*tty
)
98 struct uart_state
*state
= tty
->driver_data
;
99 struct uart_port
*port
= state
->uart_port
;
102 spin_lock_irqsave(&port
->lock
, flags
);
104 spin_unlock_irqrestore(&port
->lock
, flags
);
108 uart_update_mctrl(struct uart_port
*port
, unsigned int set
, unsigned int clear
)
113 spin_lock_irqsave(&port
->lock
, flags
);
115 port
->mctrl
= (old
& ~clear
) | set
;
116 if (old
!= port
->mctrl
)
117 port
->ops
->set_mctrl(port
, port
->mctrl
);
118 spin_unlock_irqrestore(&port
->lock
, flags
);
121 #define uart_set_mctrl(port, set) uart_update_mctrl(port, set, 0)
122 #define uart_clear_mctrl(port, clear) uart_update_mctrl(port, 0, clear)
125 * Startup the port. This will be called once per open. All calls
126 * will be serialised by the per-port mutex.
128 static int uart_port_startup(struct tty_struct
*tty
, struct uart_state
*state
,
131 struct uart_port
*uport
= state
->uart_port
;
132 struct tty_port
*port
= &state
->port
;
136 if (uport
->type
== PORT_UNKNOWN
)
140 * Initialise and allocate the transmit and temporary
143 if (!state
->xmit
.buf
) {
144 /* This is protected by the per port mutex */
145 page
= get_zeroed_page(GFP_KERNEL
);
149 state
->xmit
.buf
= (unsigned char *) page
;
150 uart_circ_clear(&state
->xmit
);
153 retval
= uport
->ops
->startup(uport
);
155 if (uart_console(uport
) && uport
->cons
->cflag
) {
156 tty
->termios
.c_cflag
= uport
->cons
->cflag
;
157 uport
->cons
->cflag
= 0;
160 * Initialise the hardware port settings.
162 uart_change_speed(tty
, state
, NULL
);
166 * Setup the RTS and DTR signals once the
167 * port is open and ready to respond.
169 if (tty
->termios
.c_cflag
& CBAUD
)
170 uart_set_mctrl(uport
, TIOCM_RTS
| TIOCM_DTR
);
173 if (tty_port_cts_enabled(port
)) {
174 spin_lock_irq(&uport
->lock
);
175 if (!(uport
->ops
->get_mctrl(uport
) & TIOCM_CTS
))
177 spin_unlock_irq(&uport
->lock
);
182 * This is to allow setserial on this port. People may want to set
183 * port/irq/type and then reconfigure the port properly if it failed
186 if (retval
&& capable(CAP_SYS_ADMIN
))
192 static int uart_startup(struct tty_struct
*tty
, struct uart_state
*state
,
195 struct tty_port
*port
= &state
->port
;
198 if (port
->flags
& ASYNC_INITIALIZED
)
202 * Set the TTY IO error marker - we will only clear this
203 * once we have successfully opened the port.
205 set_bit(TTY_IO_ERROR
, &tty
->flags
);
207 retval
= uart_port_startup(tty
, state
, init_hw
);
209 set_bit(ASYNCB_INITIALIZED
, &port
->flags
);
210 clear_bit(TTY_IO_ERROR
, &tty
->flags
);
211 } else if (retval
> 0)
218 * This routine will shutdown a serial port; interrupts are disabled, and
219 * DTR is dropped if the hangup on close termio flag is on. Calls to
220 * uart_shutdown are serialised by the per-port semaphore.
222 static void uart_shutdown(struct tty_struct
*tty
, struct uart_state
*state
)
224 struct uart_port
*uport
= state
->uart_port
;
225 struct tty_port
*port
= &state
->port
;
228 * Set the TTY IO error marker
231 set_bit(TTY_IO_ERROR
, &tty
->flags
);
233 if (test_and_clear_bit(ASYNCB_INITIALIZED
, &port
->flags
)) {
235 * Turn off DTR and RTS early.
237 if (!tty
|| (tty
->termios
.c_cflag
& HUPCL
))
238 uart_clear_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
240 uart_port_shutdown(port
);
244 * It's possible for shutdown to be called after suspend if we get
245 * a DCD drop (hangup) at just the right time. Clear suspended bit so
246 * we don't try to resume a port that has been shutdown.
248 clear_bit(ASYNCB_SUSPENDED
, &port
->flags
);
251 * Free the transmit buffer page.
253 if (state
->xmit
.buf
) {
254 free_page((unsigned long)state
->xmit
.buf
);
255 state
->xmit
.buf
= NULL
;
260 * uart_update_timeout - update per-port FIFO timeout.
261 * @port: uart_port structure describing the port
262 * @cflag: termios cflag value
263 * @baud: speed of the port
265 * Set the port FIFO timeout value. The @cflag value should
266 * reflect the actual hardware settings.
269 uart_update_timeout(struct uart_port
*port
, unsigned int cflag
,
274 /* byte size and parity */
275 switch (cflag
& CSIZE
) {
296 * The total number of bits to be transmitted in the fifo.
298 bits
= bits
* port
->fifosize
;
301 * Figure the timeout to send the above number of bits.
302 * Add .02 seconds of slop
304 port
->timeout
= (HZ
* bits
) / baud
+ HZ
/50;
307 EXPORT_SYMBOL(uart_update_timeout
);
310 * uart_get_baud_rate - return baud rate for a particular port
311 * @port: uart_port structure describing the port in question.
312 * @termios: desired termios settings.
313 * @old: old termios (or NULL)
314 * @min: minimum acceptable baud rate
315 * @max: maximum acceptable baud rate
317 * Decode the termios structure into a numeric baud rate,
318 * taking account of the magic 38400 baud rate (with spd_*
319 * flags), and mapping the %B0 rate to 9600 baud.
321 * If the new baud rate is invalid, try the old termios setting.
322 * If it's still invalid, we try 9600 baud.
324 * Update the @termios structure to reflect the baud rate
325 * we're actually going to be using. Don't do this for the case
326 * where B0 is requested ("hang up").
329 uart_get_baud_rate(struct uart_port
*port
, struct ktermios
*termios
,
330 struct ktermios
*old
, unsigned int min
, unsigned int max
)
332 unsigned int try, baud
, altbaud
= 38400;
334 upf_t flags
= port
->flags
& UPF_SPD_MASK
;
336 if (flags
== UPF_SPD_HI
)
338 else if (flags
== UPF_SPD_VHI
)
340 else if (flags
== UPF_SPD_SHI
)
342 else if (flags
== UPF_SPD_WARP
)
345 for (try = 0; try < 2; try++) {
346 baud
= tty_termios_baud_rate(termios
);
349 * The spd_hi, spd_vhi, spd_shi, spd_warp kludge...
356 * Special case: B0 rate.
363 if (baud
>= min
&& baud
<= max
)
367 * Oops, the quotient was zero. Try again with
368 * the old baud rate if possible.
370 termios
->c_cflag
&= ~CBAUD
;
372 baud
= tty_termios_baud_rate(old
);
374 tty_termios_encode_baud_rate(termios
,
381 * As a last resort, if the range cannot be met then clip to
382 * the nearest chip supported rate.
386 tty_termios_encode_baud_rate(termios
,
389 tty_termios_encode_baud_rate(termios
,
393 /* Should never happen */
398 EXPORT_SYMBOL(uart_get_baud_rate
);
401 * uart_get_divisor - return uart clock divisor
402 * @port: uart_port structure describing the port.
403 * @baud: desired baud rate
405 * Calculate the uart clock divisor for the port.
408 uart_get_divisor(struct uart_port
*port
, unsigned int baud
)
413 * Old custom speed handling.
415 if (baud
== 38400 && (port
->flags
& UPF_SPD_MASK
) == UPF_SPD_CUST
)
416 quot
= port
->custom_divisor
;
418 quot
= DIV_ROUND_CLOSEST(port
->uartclk
, 16 * baud
);
423 EXPORT_SYMBOL(uart_get_divisor
);
425 /* FIXME: Consistent locking policy */
426 static void uart_change_speed(struct tty_struct
*tty
, struct uart_state
*state
,
427 struct ktermios
*old_termios
)
429 struct tty_port
*port
= &state
->port
;
430 struct uart_port
*uport
= state
->uart_port
;
431 struct ktermios
*termios
;
434 * If we have no tty, termios, or the port does not exist,
435 * then we can't set the parameters for this port.
437 if (!tty
|| uport
->type
== PORT_UNKNOWN
)
440 termios
= &tty
->termios
;
443 * Set flags based on termios cflag
445 if (termios
->c_cflag
& CRTSCTS
)
446 set_bit(ASYNCB_CTS_FLOW
, &port
->flags
);
448 clear_bit(ASYNCB_CTS_FLOW
, &port
->flags
);
450 if (termios
->c_cflag
& CLOCAL
)
451 clear_bit(ASYNCB_CHECK_CD
, &port
->flags
);
453 set_bit(ASYNCB_CHECK_CD
, &port
->flags
);
455 uport
->ops
->set_termios(uport
, termios
, old_termios
);
458 static inline int __uart_put_char(struct uart_port
*port
,
459 struct circ_buf
*circ
, unsigned char c
)
467 spin_lock_irqsave(&port
->lock
, flags
);
468 if (uart_circ_chars_free(circ
) != 0) {
469 circ
->buf
[circ
->head
] = c
;
470 circ
->head
= (circ
->head
+ 1) & (UART_XMIT_SIZE
- 1);
473 spin_unlock_irqrestore(&port
->lock
, flags
);
477 static int uart_put_char(struct tty_struct
*tty
, unsigned char ch
)
479 struct uart_state
*state
= tty
->driver_data
;
481 return __uart_put_char(state
->uart_port
, &state
->xmit
, ch
);
484 static void uart_flush_chars(struct tty_struct
*tty
)
489 static int uart_write(struct tty_struct
*tty
,
490 const unsigned char *buf
, int count
)
492 struct uart_state
*state
= tty
->driver_data
;
493 struct uart_port
*port
;
494 struct circ_buf
*circ
;
499 * This means you called this function _after_ the port was
500 * closed. No cookie for you.
507 port
= state
->uart_port
;
513 spin_lock_irqsave(&port
->lock
, flags
);
515 c
= CIRC_SPACE_TO_END(circ
->head
, circ
->tail
, UART_XMIT_SIZE
);
520 memcpy(circ
->buf
+ circ
->head
, buf
, c
);
521 circ
->head
= (circ
->head
+ c
) & (UART_XMIT_SIZE
- 1);
526 spin_unlock_irqrestore(&port
->lock
, flags
);
532 static int uart_write_room(struct tty_struct
*tty
)
534 struct uart_state
*state
= tty
->driver_data
;
538 spin_lock_irqsave(&state
->uart_port
->lock
, flags
);
539 ret
= uart_circ_chars_free(&state
->xmit
);
540 spin_unlock_irqrestore(&state
->uart_port
->lock
, flags
);
544 static int uart_chars_in_buffer(struct tty_struct
*tty
)
546 struct uart_state
*state
= tty
->driver_data
;
550 spin_lock_irqsave(&state
->uart_port
->lock
, flags
);
551 ret
= uart_circ_chars_pending(&state
->xmit
);
552 spin_unlock_irqrestore(&state
->uart_port
->lock
, flags
);
556 static void uart_flush_buffer(struct tty_struct
*tty
)
558 struct uart_state
*state
= tty
->driver_data
;
559 struct uart_port
*port
;
563 * This means you called this function _after_ the port was
564 * closed. No cookie for you.
571 port
= state
->uart_port
;
572 pr_debug("uart_flush_buffer(%d) called\n", tty
->index
);
574 spin_lock_irqsave(&port
->lock
, flags
);
575 uart_circ_clear(&state
->xmit
);
576 if (port
->ops
->flush_buffer
)
577 port
->ops
->flush_buffer(port
);
578 spin_unlock_irqrestore(&port
->lock
, flags
);
583 * This function is used to send a high-priority XON/XOFF character to
586 static void uart_send_xchar(struct tty_struct
*tty
, char ch
)
588 struct uart_state
*state
= tty
->driver_data
;
589 struct uart_port
*port
= state
->uart_port
;
592 if (port
->ops
->send_xchar
)
593 port
->ops
->send_xchar(port
, ch
);
597 spin_lock_irqsave(&port
->lock
, flags
);
598 port
->ops
->start_tx(port
);
599 spin_unlock_irqrestore(&port
->lock
, flags
);
604 static void uart_throttle(struct tty_struct
*tty
)
606 struct uart_state
*state
= tty
->driver_data
;
607 struct uart_port
*port
= state
->uart_port
;
611 mask
|= UPF_SOFT_FLOW
;
612 if (tty
->termios
.c_cflag
& CRTSCTS
)
613 mask
|= UPF_HARD_FLOW
;
615 if (port
->flags
& mask
) {
616 port
->ops
->throttle(port
);
617 mask
&= ~port
->flags
;
620 if (mask
& UPF_SOFT_FLOW
)
621 uart_send_xchar(tty
, STOP_CHAR(tty
));
623 if (mask
& UPF_HARD_FLOW
)
624 uart_clear_mctrl(port
, TIOCM_RTS
);
627 static void uart_unthrottle(struct tty_struct
*tty
)
629 struct uart_state
*state
= tty
->driver_data
;
630 struct uart_port
*port
= state
->uart_port
;
634 mask
|= UPF_SOFT_FLOW
;
635 if (tty
->termios
.c_cflag
& CRTSCTS
)
636 mask
|= UPF_HARD_FLOW
;
638 if (port
->flags
& mask
) {
639 port
->ops
->unthrottle(port
);
640 mask
&= ~port
->flags
;
643 if (mask
& UPF_SOFT_FLOW
) {
647 uart_send_xchar(tty
, START_CHAR(tty
));
650 if (mask
& UPF_HARD_FLOW
)
651 uart_set_mctrl(port
, TIOCM_RTS
);
654 static void do_uart_get_info(struct tty_port
*port
,
655 struct serial_struct
*retinfo
)
657 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
658 struct uart_port
*uport
= state
->uart_port
;
660 memset(retinfo
, 0, sizeof(*retinfo
));
662 retinfo
->type
= uport
->type
;
663 retinfo
->line
= uport
->line
;
664 retinfo
->port
= uport
->iobase
;
665 if (HIGH_BITS_OFFSET
)
666 retinfo
->port_high
= (long) uport
->iobase
>> HIGH_BITS_OFFSET
;
667 retinfo
->irq
= uport
->irq
;
668 retinfo
->flags
= uport
->flags
;
669 retinfo
->xmit_fifo_size
= uport
->fifosize
;
670 retinfo
->baud_base
= uport
->uartclk
/ 16;
671 retinfo
->close_delay
= jiffies_to_msecs(port
->close_delay
) / 10;
672 retinfo
->closing_wait
= port
->closing_wait
== ASYNC_CLOSING_WAIT_NONE
?
673 ASYNC_CLOSING_WAIT_NONE
:
674 jiffies_to_msecs(port
->closing_wait
) / 10;
675 retinfo
->custom_divisor
= uport
->custom_divisor
;
676 retinfo
->hub6
= uport
->hub6
;
677 retinfo
->io_type
= uport
->iotype
;
678 retinfo
->iomem_reg_shift
= uport
->regshift
;
679 retinfo
->iomem_base
= (void *)(unsigned long)uport
->mapbase
;
682 static void uart_get_info(struct tty_port
*port
,
683 struct serial_struct
*retinfo
)
685 /* Ensure the state we copy is consistent and no hardware changes
687 mutex_lock(&port
->mutex
);
688 do_uart_get_info(port
, retinfo
);
689 mutex_unlock(&port
->mutex
);
692 static int uart_get_info_user(struct tty_port
*port
,
693 struct serial_struct __user
*retinfo
)
695 struct serial_struct tmp
;
696 uart_get_info(port
, &tmp
);
698 if (copy_to_user(retinfo
, &tmp
, sizeof(*retinfo
)))
703 static int uart_set_info(struct tty_struct
*tty
, struct tty_port
*port
,
704 struct uart_state
*state
,
705 struct serial_struct
*new_info
)
707 struct uart_port
*uport
= state
->uart_port
;
708 unsigned long new_port
;
709 unsigned int change_irq
, change_port
, closing_wait
;
710 unsigned int old_custom_divisor
, close_delay
;
711 upf_t old_flags
, new_flags
;
714 new_port
= new_info
->port
;
715 if (HIGH_BITS_OFFSET
)
716 new_port
+= (unsigned long) new_info
->port_high
<< HIGH_BITS_OFFSET
;
718 new_info
->irq
= irq_canonicalize(new_info
->irq
);
719 close_delay
= msecs_to_jiffies(new_info
->close_delay
* 10);
720 closing_wait
= new_info
->closing_wait
== ASYNC_CLOSING_WAIT_NONE
?
721 ASYNC_CLOSING_WAIT_NONE
:
722 msecs_to_jiffies(new_info
->closing_wait
* 10);
725 change_irq
= !(uport
->flags
& UPF_FIXED_PORT
)
726 && new_info
->irq
!= uport
->irq
;
729 * Since changing the 'type' of the port changes its resource
730 * allocations, we should treat type changes the same as
733 change_port
= !(uport
->flags
& UPF_FIXED_PORT
)
734 && (new_port
!= uport
->iobase
||
735 (unsigned long)new_info
->iomem_base
!= uport
->mapbase
||
736 new_info
->hub6
!= uport
->hub6
||
737 new_info
->io_type
!= uport
->iotype
||
738 new_info
->iomem_reg_shift
!= uport
->regshift
||
739 new_info
->type
!= uport
->type
);
741 old_flags
= uport
->flags
;
742 new_flags
= new_info
->flags
;
743 old_custom_divisor
= uport
->custom_divisor
;
745 if (!capable(CAP_SYS_ADMIN
)) {
747 if (change_irq
|| change_port
||
748 (new_info
->baud_base
!= uport
->uartclk
/ 16) ||
749 (close_delay
!= port
->close_delay
) ||
750 (closing_wait
!= port
->closing_wait
) ||
751 (new_info
->xmit_fifo_size
&&
752 new_info
->xmit_fifo_size
!= uport
->fifosize
) ||
753 (((new_flags
^ old_flags
) & ~UPF_USR_MASK
) != 0))
755 uport
->flags
= ((uport
->flags
& ~UPF_USR_MASK
) |
756 (new_flags
& UPF_USR_MASK
));
757 uport
->custom_divisor
= new_info
->custom_divisor
;
762 * Ask the low level driver to verify the settings.
764 if (uport
->ops
->verify_port
)
765 retval
= uport
->ops
->verify_port(uport
, new_info
);
767 if ((new_info
->irq
>= nr_irqs
) || (new_info
->irq
< 0) ||
768 (new_info
->baud_base
< 9600))
774 if (change_port
|| change_irq
) {
778 * Make sure that we are the sole user of this port.
780 if (tty_port_users(port
) > 1)
784 * We need to shutdown the serial port at the old
785 * port/type/irq combination.
787 uart_shutdown(tty
, state
);
791 unsigned long old_iobase
, old_mapbase
;
792 unsigned int old_type
, old_iotype
, old_hub6
, old_shift
;
794 old_iobase
= uport
->iobase
;
795 old_mapbase
= uport
->mapbase
;
796 old_type
= uport
->type
;
797 old_hub6
= uport
->hub6
;
798 old_iotype
= uport
->iotype
;
799 old_shift
= uport
->regshift
;
802 * Free and release old regions
804 if (old_type
!= PORT_UNKNOWN
)
805 uport
->ops
->release_port(uport
);
807 uport
->iobase
= new_port
;
808 uport
->type
= new_info
->type
;
809 uport
->hub6
= new_info
->hub6
;
810 uport
->iotype
= new_info
->io_type
;
811 uport
->regshift
= new_info
->iomem_reg_shift
;
812 uport
->mapbase
= (unsigned long)new_info
->iomem_base
;
815 * Claim and map the new regions
817 if (uport
->type
!= PORT_UNKNOWN
) {
818 retval
= uport
->ops
->request_port(uport
);
820 /* Always success - Jean II */
825 * If we fail to request resources for the
826 * new port, try to restore the old settings.
828 if (retval
&& old_type
!= PORT_UNKNOWN
) {
829 uport
->iobase
= old_iobase
;
830 uport
->type
= old_type
;
831 uport
->hub6
= old_hub6
;
832 uport
->iotype
= old_iotype
;
833 uport
->regshift
= old_shift
;
834 uport
->mapbase
= old_mapbase
;
835 retval
= uport
->ops
->request_port(uport
);
837 * If we failed to restore the old settings,
841 uport
->type
= PORT_UNKNOWN
;
847 /* Added to return the correct error -Ram Gupta */
853 uport
->irq
= new_info
->irq
;
854 if (!(uport
->flags
& UPF_FIXED_PORT
))
855 uport
->uartclk
= new_info
->baud_base
* 16;
856 uport
->flags
= (uport
->flags
& ~UPF_CHANGE_MASK
) |
857 (new_flags
& UPF_CHANGE_MASK
);
858 uport
->custom_divisor
= new_info
->custom_divisor
;
859 port
->close_delay
= close_delay
;
860 port
->closing_wait
= closing_wait
;
861 if (new_info
->xmit_fifo_size
)
862 uport
->fifosize
= new_info
->xmit_fifo_size
;
863 port
->low_latency
= (uport
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
867 if (uport
->type
== PORT_UNKNOWN
)
869 if (port
->flags
& ASYNC_INITIALIZED
) {
870 if (((old_flags
^ uport
->flags
) & UPF_SPD_MASK
) ||
871 old_custom_divisor
!= uport
->custom_divisor
) {
873 * If they're setting up a custom divisor or speed,
874 * instead of clearing it, then bitch about it. No
875 * need to rate-limit; it's CAP_SYS_ADMIN only.
877 if (uport
->flags
& UPF_SPD_MASK
) {
880 "%s sets custom speed on %s. This "
881 "is deprecated.\n", current
->comm
,
882 tty_name(port
->tty
, buf
));
884 uart_change_speed(tty
, state
, NULL
);
887 retval
= uart_startup(tty
, state
, 1);
892 static int uart_set_info_user(struct tty_struct
*tty
, struct uart_state
*state
,
893 struct serial_struct __user
*newinfo
)
895 struct serial_struct new_serial
;
896 struct tty_port
*port
= &state
->port
;
899 if (copy_from_user(&new_serial
, newinfo
, sizeof(new_serial
)))
903 * This semaphore protects port->count. It is also
904 * very useful to prevent opens. Also, take the
905 * port configuration semaphore to make sure that a
906 * module insertion/removal doesn't change anything
909 mutex_lock(&port
->mutex
);
910 retval
= uart_set_info(tty
, port
, state
, &new_serial
);
911 mutex_unlock(&port
->mutex
);
916 * uart_get_lsr_info - get line status register info
917 * @tty: tty associated with the UART
918 * @state: UART being queried
919 * @value: returned modem value
921 * Note: uart_ioctl protects us against hangups.
923 static int uart_get_lsr_info(struct tty_struct
*tty
,
924 struct uart_state
*state
, unsigned int __user
*value
)
926 struct uart_port
*uport
= state
->uart_port
;
929 result
= uport
->ops
->tx_empty(uport
);
932 * If we're about to load something into the transmit
933 * register, we'll pretend the transmitter isn't empty to
934 * avoid a race condition (depending on when the transmit
935 * interrupt happens).
938 ((uart_circ_chars_pending(&state
->xmit
) > 0) &&
939 !tty
->stopped
&& !tty
->hw_stopped
))
940 result
&= ~TIOCSER_TEMT
;
942 return put_user(result
, value
);
945 static int uart_tiocmget(struct tty_struct
*tty
)
947 struct uart_state
*state
= tty
->driver_data
;
948 struct tty_port
*port
= &state
->port
;
949 struct uart_port
*uport
= state
->uart_port
;
952 mutex_lock(&port
->mutex
);
953 if (!(tty
->flags
& (1 << TTY_IO_ERROR
))) {
954 result
= uport
->mctrl
;
955 spin_lock_irq(&uport
->lock
);
956 result
|= uport
->ops
->get_mctrl(uport
);
957 spin_unlock_irq(&uport
->lock
);
959 mutex_unlock(&port
->mutex
);
965 uart_tiocmset(struct tty_struct
*tty
, unsigned int set
, unsigned int clear
)
967 struct uart_state
*state
= tty
->driver_data
;
968 struct uart_port
*uport
= state
->uart_port
;
969 struct tty_port
*port
= &state
->port
;
972 mutex_lock(&port
->mutex
);
973 if (!(tty
->flags
& (1 << TTY_IO_ERROR
))) {
974 uart_update_mctrl(uport
, set
, clear
);
977 mutex_unlock(&port
->mutex
);
981 static int uart_break_ctl(struct tty_struct
*tty
, int break_state
)
983 struct uart_state
*state
= tty
->driver_data
;
984 struct tty_port
*port
= &state
->port
;
985 struct uart_port
*uport
= state
->uart_port
;
987 mutex_lock(&port
->mutex
);
989 if (uport
->type
!= PORT_UNKNOWN
)
990 uport
->ops
->break_ctl(uport
, break_state
);
992 mutex_unlock(&port
->mutex
);
996 static int uart_do_autoconfig(struct tty_struct
*tty
,struct uart_state
*state
)
998 struct uart_port
*uport
= state
->uart_port
;
999 struct tty_port
*port
= &state
->port
;
1002 if (!capable(CAP_SYS_ADMIN
))
1006 * Take the per-port semaphore. This prevents count from
1007 * changing, and hence any extra opens of the port while
1008 * we're auto-configuring.
1010 if (mutex_lock_interruptible(&port
->mutex
))
1011 return -ERESTARTSYS
;
1014 if (tty_port_users(port
) == 1) {
1015 uart_shutdown(tty
, state
);
1018 * If we already have a port type configured,
1019 * we must release its resources.
1021 if (uport
->type
!= PORT_UNKNOWN
)
1022 uport
->ops
->release_port(uport
);
1024 flags
= UART_CONFIG_TYPE
;
1025 if (uport
->flags
& UPF_AUTO_IRQ
)
1026 flags
|= UART_CONFIG_IRQ
;
1029 * This will claim the ports resources if
1032 uport
->ops
->config_port(uport
, flags
);
1034 ret
= uart_startup(tty
, state
, 1);
1036 mutex_unlock(&port
->mutex
);
1041 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1042 * - mask passed in arg for lines of interest
1043 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1044 * Caller should use TIOCGICOUNT to see which one it was
1046 * FIXME: This wants extracting into a common all driver implementation
1047 * of TIOCMWAIT using tty_port.
1050 uart_wait_modem_status(struct uart_state
*state
, unsigned long arg
)
1052 struct uart_port
*uport
= state
->uart_port
;
1053 struct tty_port
*port
= &state
->port
;
1054 DECLARE_WAITQUEUE(wait
, current
);
1055 struct uart_icount cprev
, cnow
;
1059 * note the counters on entry
1061 spin_lock_irq(&uport
->lock
);
1062 memcpy(&cprev
, &uport
->icount
, sizeof(struct uart_icount
));
1065 * Force modem status interrupts on
1067 uport
->ops
->enable_ms(uport
);
1068 spin_unlock_irq(&uport
->lock
);
1070 add_wait_queue(&port
->delta_msr_wait
, &wait
);
1072 spin_lock_irq(&uport
->lock
);
1073 memcpy(&cnow
, &uport
->icount
, sizeof(struct uart_icount
));
1074 spin_unlock_irq(&uport
->lock
);
1076 set_current_state(TASK_INTERRUPTIBLE
);
1078 if (((arg
& TIOCM_RNG
) && (cnow
.rng
!= cprev
.rng
)) ||
1079 ((arg
& TIOCM_DSR
) && (cnow
.dsr
!= cprev
.dsr
)) ||
1080 ((arg
& TIOCM_CD
) && (cnow
.dcd
!= cprev
.dcd
)) ||
1081 ((arg
& TIOCM_CTS
) && (cnow
.cts
!= cprev
.cts
))) {
1088 /* see if a signal did it */
1089 if (signal_pending(current
)) {
1097 current
->state
= TASK_RUNNING
;
1098 remove_wait_queue(&port
->delta_msr_wait
, &wait
);
1104 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1105 * Return: write counters to the user passed counter struct
1106 * NB: both 1->0 and 0->1 transitions are counted except for
1107 * RI where only 0->1 is counted.
1109 static int uart_get_icount(struct tty_struct
*tty
,
1110 struct serial_icounter_struct
*icount
)
1112 struct uart_state
*state
= tty
->driver_data
;
1113 struct uart_icount cnow
;
1114 struct uart_port
*uport
= state
->uart_port
;
1116 spin_lock_irq(&uport
->lock
);
1117 memcpy(&cnow
, &uport
->icount
, sizeof(struct uart_icount
));
1118 spin_unlock_irq(&uport
->lock
);
1120 icount
->cts
= cnow
.cts
;
1121 icount
->dsr
= cnow
.dsr
;
1122 icount
->rng
= cnow
.rng
;
1123 icount
->dcd
= cnow
.dcd
;
1124 icount
->rx
= cnow
.rx
;
1125 icount
->tx
= cnow
.tx
;
1126 icount
->frame
= cnow
.frame
;
1127 icount
->overrun
= cnow
.overrun
;
1128 icount
->parity
= cnow
.parity
;
1129 icount
->brk
= cnow
.brk
;
1130 icount
->buf_overrun
= cnow
.buf_overrun
;
1136 * Called via sys_ioctl. We can use spin_lock_irq() here.
1139 uart_ioctl(struct tty_struct
*tty
, unsigned int cmd
,
1142 struct uart_state
*state
= tty
->driver_data
;
1143 struct tty_port
*port
= &state
->port
;
1144 void __user
*uarg
= (void __user
*)arg
;
1145 int ret
= -ENOIOCTLCMD
;
1149 * These ioctls don't rely on the hardware to be present.
1153 ret
= uart_get_info_user(port
, uarg
);
1157 ret
= uart_set_info_user(tty
, state
, uarg
);
1161 ret
= uart_do_autoconfig(tty
, state
);
1164 case TIOCSERGWILD
: /* obsolete */
1165 case TIOCSERSWILD
: /* obsolete */
1170 if (ret
!= -ENOIOCTLCMD
)
1173 if (tty
->flags
& (1 << TTY_IO_ERROR
)) {
1179 * The following should only be used when hardware is present.
1183 ret
= uart_wait_modem_status(state
, arg
);
1187 if (ret
!= -ENOIOCTLCMD
)
1190 mutex_lock(&port
->mutex
);
1192 if (tty
->flags
& (1 << TTY_IO_ERROR
)) {
1198 * All these rely on hardware being present and need to be
1199 * protected against the tty being hung up.
1202 case TIOCSERGETLSR
: /* Get line status register */
1203 ret
= uart_get_lsr_info(tty
, state
, uarg
);
1207 struct uart_port
*uport
= state
->uart_port
;
1208 if (uport
->ops
->ioctl
)
1209 ret
= uport
->ops
->ioctl(uport
, cmd
, arg
);
1214 mutex_unlock(&port
->mutex
);
1219 static void uart_set_ldisc(struct tty_struct
*tty
)
1221 struct uart_state
*state
= tty
->driver_data
;
1222 struct uart_port
*uport
= state
->uart_port
;
1224 if (uport
->ops
->set_ldisc
)
1225 uport
->ops
->set_ldisc(uport
, tty
->termios
.c_line
);
1228 static void uart_set_termios(struct tty_struct
*tty
,
1229 struct ktermios
*old_termios
)
1231 struct uart_state
*state
= tty
->driver_data
;
1232 struct uart_port
*uport
= state
->uart_port
;
1233 unsigned long flags
;
1234 unsigned int cflag
= tty
->termios
.c_cflag
;
1235 unsigned int iflag_mask
= IGNBRK
|BRKINT
|IGNPAR
|PARMRK
|INPCK
;
1236 bool sw_changed
= false;
1239 * Drivers doing software flow control also need to know
1240 * about changes to these input settings.
1242 if (uport
->flags
& UPF_SOFT_FLOW
) {
1243 iflag_mask
|= IXANY
|IXON
|IXOFF
;
1245 tty
->termios
.c_cc
[VSTART
] != old_termios
->c_cc
[VSTART
] ||
1246 tty
->termios
.c_cc
[VSTOP
] != old_termios
->c_cc
[VSTOP
];
1250 * These are the bits that are used to setup various
1251 * flags in the low level driver. We can ignore the Bfoo
1252 * bits in c_cflag; c_[io]speed will always be set
1253 * appropriately by set_termios() in tty_ioctl.c
1255 if ((cflag
^ old_termios
->c_cflag
) == 0 &&
1256 tty
->termios
.c_ospeed
== old_termios
->c_ospeed
&&
1257 tty
->termios
.c_ispeed
== old_termios
->c_ispeed
&&
1258 ((tty
->termios
.c_iflag
^ old_termios
->c_iflag
) & iflag_mask
) == 0 &&
1263 uart_change_speed(tty
, state
, old_termios
);
1265 /* Handle transition to B0 status */
1266 if ((old_termios
->c_cflag
& CBAUD
) && !(cflag
& CBAUD
))
1267 uart_clear_mctrl(uport
, TIOCM_RTS
| TIOCM_DTR
);
1268 /* Handle transition away from B0 status */
1269 else if (!(old_termios
->c_cflag
& CBAUD
) && (cflag
& CBAUD
)) {
1270 unsigned int mask
= TIOCM_DTR
;
1271 if (!(cflag
& CRTSCTS
) ||
1272 !test_bit(TTY_THROTTLED
, &tty
->flags
))
1274 uart_set_mctrl(uport
, mask
);
1278 * If the port is doing h/w assisted flow control, do nothing.
1279 * We assume that tty->hw_stopped has never been set.
1281 if (uport
->flags
& UPF_HARD_FLOW
)
1284 /* Handle turning off CRTSCTS */
1285 if ((old_termios
->c_cflag
& CRTSCTS
) && !(cflag
& CRTSCTS
)) {
1286 spin_lock_irqsave(&uport
->lock
, flags
);
1287 tty
->hw_stopped
= 0;
1289 spin_unlock_irqrestore(&uport
->lock
, flags
);
1291 /* Handle turning on CRTSCTS */
1292 else if (!(old_termios
->c_cflag
& CRTSCTS
) && (cflag
& CRTSCTS
)) {
1293 spin_lock_irqsave(&uport
->lock
, flags
);
1294 if (!(uport
->ops
->get_mctrl(uport
) & TIOCM_CTS
)) {
1295 tty
->hw_stopped
= 1;
1296 uport
->ops
->stop_tx(uport
);
1298 spin_unlock_irqrestore(&uport
->lock
, flags
);
1303 * Calls to uart_close() are serialised via the tty_lock in
1304 * drivers/tty/tty_io.c:tty_release()
1305 * drivers/tty/tty_io.c:do_tty_hangup()
1306 * This runs from a workqueue and can sleep for a _short_ time only.
1308 static void uart_close(struct tty_struct
*tty
, struct file
*filp
)
1310 struct uart_state
*state
= tty
->driver_data
;
1311 struct tty_port
*port
;
1312 struct uart_port
*uport
;
1313 unsigned long flags
;
1318 uport
= state
->uart_port
;
1319 port
= &state
->port
;
1321 pr_debug("uart_close(%d) called\n", uport
? uport
->line
: -1);
1323 if (!port
->count
|| tty_port_close_start(port
, tty
, filp
) == 0)
1327 * At this point, we stop accepting input. To do this, we
1328 * disable the receive line status interrupts.
1330 if (port
->flags
& ASYNC_INITIALIZED
) {
1331 unsigned long flags
;
1332 spin_lock_irqsave(&uport
->lock
, flags
);
1333 uport
->ops
->stop_rx(uport
);
1334 spin_unlock_irqrestore(&uport
->lock
, flags
);
1336 * Before we drop DTR, make sure the UART transmitter
1337 * has completely drained; this is especially
1338 * important if there is a transmit FIFO!
1340 uart_wait_until_sent(tty
, uport
->timeout
);
1343 mutex_lock(&port
->mutex
);
1344 uart_shutdown(tty
, state
);
1345 uart_flush_buffer(tty
);
1347 tty_ldisc_flush(tty
);
1349 tty_port_tty_set(port
, NULL
);
1350 spin_lock_irqsave(&port
->lock
, flags
);
1353 if (port
->blocked_open
) {
1354 spin_unlock_irqrestore(&port
->lock
, flags
);
1355 if (port
->close_delay
)
1356 msleep_interruptible(
1357 jiffies_to_msecs(port
->close_delay
));
1358 spin_lock_irqsave(&port
->lock
, flags
);
1359 } else if (!uart_console(uport
)) {
1360 spin_unlock_irqrestore(&port
->lock
, flags
);
1361 uart_change_pm(state
, UART_PM_STATE_OFF
);
1362 spin_lock_irqsave(&port
->lock
, flags
);
1366 * Wake up anyone trying to open this port.
1368 clear_bit(ASYNCB_NORMAL_ACTIVE
, &port
->flags
);
1369 clear_bit(ASYNCB_CLOSING
, &port
->flags
);
1370 spin_unlock_irqrestore(&port
->lock
, flags
);
1371 wake_up_interruptible(&port
->open_wait
);
1372 wake_up_interruptible(&port
->close_wait
);
1374 mutex_unlock(&port
->mutex
);
1377 static void uart_wait_until_sent(struct tty_struct
*tty
, int timeout
)
1379 struct uart_state
*state
= tty
->driver_data
;
1380 struct uart_port
*port
= state
->uart_port
;
1381 unsigned long char_time
, expire
;
1383 if (port
->type
== PORT_UNKNOWN
|| port
->fifosize
== 0)
1387 * Set the check interval to be 1/5 of the estimated time to
1388 * send a single character, and make it at least 1. The check
1389 * interval should also be less than the timeout.
1391 * Note: we have to use pretty tight timings here to satisfy
1394 char_time
= (port
->timeout
- HZ
/50) / port
->fifosize
;
1395 char_time
= char_time
/ 5;
1398 if (timeout
&& timeout
< char_time
)
1399 char_time
= timeout
;
1402 * If the transmitter hasn't cleared in twice the approximate
1403 * amount of time to send the entire FIFO, it probably won't
1404 * ever clear. This assumes the UART isn't doing flow
1405 * control, which is currently the case. Hence, if it ever
1406 * takes longer than port->timeout, this is probably due to a
1407 * UART bug of some kind. So, we clamp the timeout parameter at
1410 if (timeout
== 0 || timeout
> 2 * port
->timeout
)
1411 timeout
= 2 * port
->timeout
;
1413 expire
= jiffies
+ timeout
;
1415 pr_debug("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n",
1416 port
->line
, jiffies
, expire
);
1419 * Check whether the transmitter is empty every 'char_time'.
1420 * 'timeout' / 'expire' give us the maximum amount of time
1423 while (!port
->ops
->tx_empty(port
)) {
1424 msleep_interruptible(jiffies_to_msecs(char_time
));
1425 if (signal_pending(current
))
1427 if (time_after(jiffies
, expire
))
1433 * Calls to uart_hangup() are serialised by the tty_lock in
1434 * drivers/tty/tty_io.c:do_tty_hangup()
1435 * This runs from a workqueue and can sleep for a _short_ time only.
1437 static void uart_hangup(struct tty_struct
*tty
)
1439 struct uart_state
*state
= tty
->driver_data
;
1440 struct tty_port
*port
= &state
->port
;
1441 unsigned long flags
;
1443 pr_debug("uart_hangup(%d)\n", state
->uart_port
->line
);
1445 mutex_lock(&port
->mutex
);
1446 if (port
->flags
& ASYNC_NORMAL_ACTIVE
) {
1447 uart_flush_buffer(tty
);
1448 uart_shutdown(tty
, state
);
1449 spin_lock_irqsave(&port
->lock
, flags
);
1451 clear_bit(ASYNCB_NORMAL_ACTIVE
, &port
->flags
);
1452 spin_unlock_irqrestore(&port
->lock
, flags
);
1453 tty_port_tty_set(port
, NULL
);
1454 if (!uart_console(state
->uart_port
))
1455 uart_change_pm(state
, UART_PM_STATE_OFF
);
1456 wake_up_interruptible(&port
->open_wait
);
1457 wake_up_interruptible(&port
->delta_msr_wait
);
1459 mutex_unlock(&port
->mutex
);
1462 static int uart_port_activate(struct tty_port
*port
, struct tty_struct
*tty
)
1467 static void uart_port_shutdown(struct tty_port
*port
)
1469 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1470 struct uart_port
*uport
= state
->uart_port
;
1473 * clear delta_msr_wait queue to avoid mem leaks: we may free
1474 * the irq here so the queue might never be woken up. Note
1475 * that we won't end up waiting on delta_msr_wait again since
1476 * any outstanding file descriptors should be pointing at
1477 * hung_up_tty_fops now.
1479 wake_up_interruptible(&port
->delta_msr_wait
);
1482 * Free the IRQ and disable the port.
1484 uport
->ops
->shutdown(uport
);
1487 * Ensure that the IRQ handler isn't running on another CPU.
1489 synchronize_irq(uport
->irq
);
1492 static int uart_carrier_raised(struct tty_port
*port
)
1494 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1495 struct uart_port
*uport
= state
->uart_port
;
1497 spin_lock_irq(&uport
->lock
);
1498 uport
->ops
->enable_ms(uport
);
1499 mctrl
= uport
->ops
->get_mctrl(uport
);
1500 spin_unlock_irq(&uport
->lock
);
1501 if (mctrl
& TIOCM_CAR
)
1506 static void uart_dtr_rts(struct tty_port
*port
, int onoff
)
1508 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1509 struct uart_port
*uport
= state
->uart_port
;
1512 uart_set_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
1514 uart_clear_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
1518 * Calls to uart_open are serialised by the tty_lock in
1519 * drivers/tty/tty_io.c:tty_open()
1520 * Note that if this fails, then uart_close() _will_ be called.
1522 * In time, we want to scrap the "opening nonpresent ports"
1523 * behaviour and implement an alternative way for setserial
1524 * to set base addresses/ports/types. This will allow us to
1525 * get rid of a certain amount of extra tests.
1527 static int uart_open(struct tty_struct
*tty
, struct file
*filp
)
1529 struct uart_driver
*drv
= (struct uart_driver
*)tty
->driver
->driver_state
;
1530 int retval
, line
= tty
->index
;
1531 struct uart_state
*state
= drv
->state
+ line
;
1532 struct tty_port
*port
= &state
->port
;
1534 pr_debug("uart_open(%d) called\n", line
);
1537 * We take the semaphore here to guarantee that we won't be re-entered
1538 * while allocating the state structure, or while we request any IRQs
1539 * that the driver may need. This also has the nice side-effect that
1540 * it delays the action of uart_hangup, so we can guarantee that
1541 * state->port.tty will always contain something reasonable.
1543 if (mutex_lock_interruptible(&port
->mutex
)) {
1544 retval
= -ERESTARTSYS
;
1549 if (!state
->uart_port
|| state
->uart_port
->flags
& UPF_DEAD
) {
1555 * Once we set tty->driver_data here, we are guaranteed that
1556 * uart_close() will decrement the driver module use count.
1557 * Any failures from here onwards should not touch the count.
1559 tty
->driver_data
= state
;
1560 state
->uart_port
->state
= state
;
1561 state
->port
.low_latency
=
1562 (state
->uart_port
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
1563 tty_port_tty_set(port
, tty
);
1566 * If the port is in the middle of closing, bail out now.
1568 if (tty_hung_up_p(filp
)) {
1574 * Make sure the device is in D0 state.
1576 if (port
->count
== 1)
1577 uart_change_pm(state
, UART_PM_STATE_ON
);
1580 * Start up the serial port.
1582 retval
= uart_startup(tty
, state
, 0);
1585 * If we succeeded, wait until the port is ready.
1587 mutex_unlock(&port
->mutex
);
1589 retval
= tty_port_block_til_ready(port
, tty
, filp
);
1595 mutex_unlock(&port
->mutex
);
1599 static const char *uart_type(struct uart_port
*port
)
1601 const char *str
= NULL
;
1603 if (port
->ops
->type
)
1604 str
= port
->ops
->type(port
);
1612 #ifdef CONFIG_PROC_FS
1614 static void uart_line_info(struct seq_file
*m
, struct uart_driver
*drv
, int i
)
1616 struct uart_state
*state
= drv
->state
+ i
;
1617 struct tty_port
*port
= &state
->port
;
1618 enum uart_pm_state pm_state
;
1619 struct uart_port
*uport
= state
->uart_port
;
1621 unsigned int status
;
1627 mmio
= uport
->iotype
>= UPIO_MEM
;
1628 seq_printf(m
, "%d: uart:%s %s%08llX irq:%d",
1629 uport
->line
, uart_type(uport
),
1630 mmio
? "mmio:0x" : "port:",
1631 mmio
? (unsigned long long)uport
->mapbase
1632 : (unsigned long long)uport
->iobase
,
1635 if (uport
->type
== PORT_UNKNOWN
) {
1640 if (capable(CAP_SYS_ADMIN
)) {
1641 mutex_lock(&port
->mutex
);
1642 pm_state
= state
->pm_state
;
1643 if (pm_state
!= UART_PM_STATE_ON
)
1644 uart_change_pm(state
, UART_PM_STATE_ON
);
1645 spin_lock_irq(&uport
->lock
);
1646 status
= uport
->ops
->get_mctrl(uport
);
1647 spin_unlock_irq(&uport
->lock
);
1648 if (pm_state
!= UART_PM_STATE_ON
)
1649 uart_change_pm(state
, pm_state
);
1650 mutex_unlock(&port
->mutex
);
1652 seq_printf(m
, " tx:%d rx:%d",
1653 uport
->icount
.tx
, uport
->icount
.rx
);
1654 if (uport
->icount
.frame
)
1655 seq_printf(m
, " fe:%d",
1656 uport
->icount
.frame
);
1657 if (uport
->icount
.parity
)
1658 seq_printf(m
, " pe:%d",
1659 uport
->icount
.parity
);
1660 if (uport
->icount
.brk
)
1661 seq_printf(m
, " brk:%d",
1663 if (uport
->icount
.overrun
)
1664 seq_printf(m
, " oe:%d",
1665 uport
->icount
.overrun
);
1667 #define INFOBIT(bit, str) \
1668 if (uport->mctrl & (bit)) \
1669 strncat(stat_buf, (str), sizeof(stat_buf) - \
1670 strlen(stat_buf) - 2)
1671 #define STATBIT(bit, str) \
1672 if (status & (bit)) \
1673 strncat(stat_buf, (str), sizeof(stat_buf) - \
1674 strlen(stat_buf) - 2)
1678 INFOBIT(TIOCM_RTS
, "|RTS");
1679 STATBIT(TIOCM_CTS
, "|CTS");
1680 INFOBIT(TIOCM_DTR
, "|DTR");
1681 STATBIT(TIOCM_DSR
, "|DSR");
1682 STATBIT(TIOCM_CAR
, "|CD");
1683 STATBIT(TIOCM_RNG
, "|RI");
1687 seq_puts(m
, stat_buf
);
1694 static int uart_proc_show(struct seq_file
*m
, void *v
)
1696 struct tty_driver
*ttydrv
= m
->private;
1697 struct uart_driver
*drv
= ttydrv
->driver_state
;
1700 seq_printf(m
, "serinfo:1.0 driver%s%s revision:%s\n",
1702 for (i
= 0; i
< drv
->nr
; i
++)
1703 uart_line_info(m
, drv
, i
);
1707 static int uart_proc_open(struct inode
*inode
, struct file
*file
)
1709 return single_open(file
, uart_proc_show
, PDE_DATA(inode
));
1712 static const struct file_operations uart_proc_fops
= {
1713 .owner
= THIS_MODULE
,
1714 .open
= uart_proc_open
,
1716 .llseek
= seq_lseek
,
1717 .release
= single_release
,
1721 #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(CONFIG_CONSOLE_POLL)
1723 * uart_console_write - write a console message to a serial port
1724 * @port: the port to write the message
1725 * @s: array of characters
1726 * @count: number of characters in string to write
1727 * @write: function to write character to port
1729 void uart_console_write(struct uart_port
*port
, const char *s
,
1731 void (*putchar
)(struct uart_port
*, int))
1735 for (i
= 0; i
< count
; i
++, s
++) {
1737 putchar(port
, '\r');
1741 EXPORT_SYMBOL_GPL(uart_console_write
);
1744 * Check whether an invalid uart number has been specified, and
1745 * if so, search for the first available port that does have
1748 struct uart_port
* __init
1749 uart_get_console(struct uart_port
*ports
, int nr
, struct console
*co
)
1751 int idx
= co
->index
;
1753 if (idx
< 0 || idx
>= nr
|| (ports
[idx
].iobase
== 0 &&
1754 ports
[idx
].membase
== NULL
))
1755 for (idx
= 0; idx
< nr
; idx
++)
1756 if (ports
[idx
].iobase
!= 0 ||
1757 ports
[idx
].membase
!= NULL
)
1766 * uart_parse_options - Parse serial port baud/parity/bits/flow control.
1767 * @options: pointer to option string
1768 * @baud: pointer to an 'int' variable for the baud rate.
1769 * @parity: pointer to an 'int' variable for the parity.
1770 * @bits: pointer to an 'int' variable for the number of data bits.
1771 * @flow: pointer to an 'int' variable for the flow control character.
1773 * uart_parse_options decodes a string containing the serial console
1774 * options. The format of the string is <baud><parity><bits><flow>,
1778 uart_parse_options(char *options
, int *baud
, int *parity
, int *bits
, int *flow
)
1782 *baud
= simple_strtoul(s
, NULL
, 10);
1783 while (*s
>= '0' && *s
<= '9')
1792 EXPORT_SYMBOL_GPL(uart_parse_options
);
1799 static const struct baud_rates baud_rates
[] = {
1800 { 921600, B921600
},
1801 { 460800, B460800
},
1802 { 230400, B230400
},
1803 { 115200, B115200
},
1815 * uart_set_options - setup the serial console parameters
1816 * @port: pointer to the serial ports uart_port structure
1817 * @co: console pointer
1819 * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even)
1820 * @bits: number of data bits
1821 * @flow: flow control character - 'r' (rts)
1824 uart_set_options(struct uart_port
*port
, struct console
*co
,
1825 int baud
, int parity
, int bits
, int flow
)
1827 struct ktermios termios
;
1828 static struct ktermios dummy
;
1832 * Ensure that the serial console lock is initialised
1834 * If this port is a console, then the spinlock is already
1837 if (!(uart_console(port
) && (port
->cons
->flags
& CON_ENABLED
))) {
1838 spin_lock_init(&port
->lock
);
1839 lockdep_set_class(&port
->lock
, &port_lock_key
);
1842 memset(&termios
, 0, sizeof(struct ktermios
));
1844 termios
.c_cflag
= CREAD
| HUPCL
| CLOCAL
;
1847 * Construct a cflag setting.
1849 for (i
= 0; baud_rates
[i
].rate
; i
++)
1850 if (baud_rates
[i
].rate
<= baud
)
1853 termios
.c_cflag
|= baud_rates
[i
].cflag
;
1856 termios
.c_cflag
|= CS7
;
1858 termios
.c_cflag
|= CS8
;
1862 termios
.c_cflag
|= PARODD
;
1865 termios
.c_cflag
|= PARENB
;
1870 termios
.c_cflag
|= CRTSCTS
;
1873 * some uarts on other side don't support no flow control.
1874 * So we set * DTR in host uart to make them happy
1876 port
->mctrl
|= TIOCM_DTR
;
1878 port
->ops
->set_termios(port
, &termios
, &dummy
);
1880 * Allow the setting of the UART parameters with a NULL console
1884 co
->cflag
= termios
.c_cflag
;
1888 EXPORT_SYMBOL_GPL(uart_set_options
);
1889 #endif /* CONFIG_SERIAL_CORE_CONSOLE */
1892 * uart_change_pm - set power state of the port
1894 * @state: port descriptor
1895 * @pm_state: new state
1897 * Locking: port->mutex has to be held
1899 static void uart_change_pm(struct uart_state
*state
,
1900 enum uart_pm_state pm_state
)
1902 struct uart_port
*port
= state
->uart_port
;
1904 if (state
->pm_state
!= pm_state
) {
1906 port
->ops
->pm(port
, pm_state
, state
->pm_state
);
1907 state
->pm_state
= pm_state
;
1912 struct uart_port
*port
;
1913 struct uart_driver
*driver
;
1916 static int serial_match_port(struct device
*dev
, void *data
)
1918 struct uart_match
*match
= data
;
1919 struct tty_driver
*tty_drv
= match
->driver
->tty_driver
;
1920 dev_t devt
= MKDEV(tty_drv
->major
, tty_drv
->minor_start
) +
1923 return dev
->devt
== devt
; /* Actually, only one tty per port */
1926 int uart_suspend_port(struct uart_driver
*drv
, struct uart_port
*uport
)
1928 struct uart_state
*state
= drv
->state
+ uport
->line
;
1929 struct tty_port
*port
= &state
->port
;
1930 struct device
*tty_dev
;
1931 struct uart_match match
= {uport
, drv
};
1933 mutex_lock(&port
->mutex
);
1935 tty_dev
= device_find_child(uport
->dev
, &match
, serial_match_port
);
1936 if (device_may_wakeup(tty_dev
)) {
1937 if (!enable_irq_wake(uport
->irq
))
1938 uport
->irq_wake
= 1;
1939 put_device(tty_dev
);
1940 mutex_unlock(&port
->mutex
);
1943 put_device(tty_dev
);
1945 if (console_suspend_enabled
|| !uart_console(uport
))
1946 uport
->suspended
= 1;
1948 if (port
->flags
& ASYNC_INITIALIZED
) {
1949 const struct uart_ops
*ops
= uport
->ops
;
1952 if (console_suspend_enabled
|| !uart_console(uport
)) {
1953 set_bit(ASYNCB_SUSPENDED
, &port
->flags
);
1954 clear_bit(ASYNCB_INITIALIZED
, &port
->flags
);
1956 spin_lock_irq(&uport
->lock
);
1957 ops
->stop_tx(uport
);
1958 ops
->set_mctrl(uport
, 0);
1959 ops
->stop_rx(uport
);
1960 spin_unlock_irq(&uport
->lock
);
1964 * Wait for the transmitter to empty.
1966 for (tries
= 3; !ops
->tx_empty(uport
) && tries
; tries
--)
1969 printk(KERN_ERR
"%s%s%s%d: Unable to drain "
1971 uport
->dev
? dev_name(uport
->dev
) : "",
1972 uport
->dev
? ": " : "",
1974 drv
->tty_driver
->name_base
+ uport
->line
);
1976 if (console_suspend_enabled
|| !uart_console(uport
))
1977 ops
->shutdown(uport
);
1981 * Disable the console device before suspending.
1983 if (console_suspend_enabled
&& uart_console(uport
))
1984 console_stop(uport
->cons
);
1986 if (console_suspend_enabled
|| !uart_console(uport
))
1987 uart_change_pm(state
, UART_PM_STATE_OFF
);
1989 mutex_unlock(&port
->mutex
);
1994 int uart_resume_port(struct uart_driver
*drv
, struct uart_port
*uport
)
1996 struct uart_state
*state
= drv
->state
+ uport
->line
;
1997 struct tty_port
*port
= &state
->port
;
1998 struct device
*tty_dev
;
1999 struct uart_match match
= {uport
, drv
};
2000 struct ktermios termios
;
2002 mutex_lock(&port
->mutex
);
2004 tty_dev
= device_find_child(uport
->dev
, &match
, serial_match_port
);
2005 if (!uport
->suspended
&& device_may_wakeup(tty_dev
)) {
2006 if (uport
->irq_wake
) {
2007 disable_irq_wake(uport
->irq
);
2008 uport
->irq_wake
= 0;
2010 put_device(tty_dev
);
2011 mutex_unlock(&port
->mutex
);
2014 put_device(tty_dev
);
2015 uport
->suspended
= 0;
2018 * Re-enable the console device after suspending.
2020 if (uart_console(uport
)) {
2022 * First try to use the console cflag setting.
2024 memset(&termios
, 0, sizeof(struct ktermios
));
2025 termios
.c_cflag
= uport
->cons
->cflag
;
2028 * If that's unset, use the tty termios setting.
2030 if (port
->tty
&& termios
.c_cflag
== 0)
2031 termios
= port
->tty
->termios
;
2033 if (console_suspend_enabled
)
2034 uart_change_pm(state
, UART_PM_STATE_ON
);
2035 uport
->ops
->set_termios(uport
, &termios
, NULL
);
2036 if (console_suspend_enabled
)
2037 console_start(uport
->cons
);
2040 if (port
->flags
& ASYNC_SUSPENDED
) {
2041 const struct uart_ops
*ops
= uport
->ops
;
2044 uart_change_pm(state
, UART_PM_STATE_ON
);
2045 spin_lock_irq(&uport
->lock
);
2046 ops
->set_mctrl(uport
, 0);
2047 spin_unlock_irq(&uport
->lock
);
2048 if (console_suspend_enabled
|| !uart_console(uport
)) {
2049 /* Protected by port mutex for now */
2050 struct tty_struct
*tty
= port
->tty
;
2051 ret
= ops
->startup(uport
);
2054 uart_change_speed(tty
, state
, NULL
);
2055 spin_lock_irq(&uport
->lock
);
2056 ops
->set_mctrl(uport
, uport
->mctrl
);
2057 ops
->start_tx(uport
);
2058 spin_unlock_irq(&uport
->lock
);
2059 set_bit(ASYNCB_INITIALIZED
, &port
->flags
);
2062 * Failed to resume - maybe hardware went away?
2063 * Clear the "initialized" flag so we won't try
2064 * to call the low level drivers shutdown method.
2066 uart_shutdown(tty
, state
);
2070 clear_bit(ASYNCB_SUSPENDED
, &port
->flags
);
2073 mutex_unlock(&port
->mutex
);
2079 uart_report_port(struct uart_driver
*drv
, struct uart_port
*port
)
2083 switch (port
->iotype
) {
2085 snprintf(address
, sizeof(address
), "I/O 0x%lx", port
->iobase
);
2088 snprintf(address
, sizeof(address
),
2089 "I/O 0x%lx offset 0x%x", port
->iobase
, port
->hub6
);
2095 snprintf(address
, sizeof(address
),
2096 "MMIO 0x%llx", (unsigned long long)port
->mapbase
);
2099 strlcpy(address
, "*unknown*", sizeof(address
));
2103 printk(KERN_INFO
"%s%s%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
2104 port
->dev
? dev_name(port
->dev
) : "",
2105 port
->dev
? ": " : "",
2107 drv
->tty_driver
->name_base
+ port
->line
,
2108 address
, port
->irq
, port
->uartclk
/ 16, uart_type(port
));
2112 uart_configure_port(struct uart_driver
*drv
, struct uart_state
*state
,
2113 struct uart_port
*port
)
2118 * If there isn't a port here, don't do anything further.
2120 if (!port
->iobase
&& !port
->mapbase
&& !port
->membase
)
2124 * Now do the auto configuration stuff. Note that config_port
2125 * is expected to claim the resources and map the port for us.
2128 if (port
->flags
& UPF_AUTO_IRQ
)
2129 flags
|= UART_CONFIG_IRQ
;
2130 if (port
->flags
& UPF_BOOT_AUTOCONF
) {
2131 if (!(port
->flags
& UPF_FIXED_TYPE
)) {
2132 port
->type
= PORT_UNKNOWN
;
2133 flags
|= UART_CONFIG_TYPE
;
2135 port
->ops
->config_port(port
, flags
);
2138 if (port
->type
!= PORT_UNKNOWN
) {
2139 unsigned long flags
;
2141 uart_report_port(drv
, port
);
2143 /* Power up port for set_mctrl() */
2144 uart_change_pm(state
, UART_PM_STATE_ON
);
2147 * Ensure that the modem control lines are de-activated.
2148 * keep the DTR setting that is set in uart_set_options()
2149 * We probably don't need a spinlock around this, but
2151 spin_lock_irqsave(&port
->lock
, flags
);
2152 port
->ops
->set_mctrl(port
, port
->mctrl
& TIOCM_DTR
);
2153 spin_unlock_irqrestore(&port
->lock
, flags
);
2156 * If this driver supports console, and it hasn't been
2157 * successfully registered yet, try to re-register it.
2158 * It may be that the port was not available.
2160 if (port
->cons
&& !(port
->cons
->flags
& CON_ENABLED
))
2161 register_console(port
->cons
);
2164 * Power down all ports by default, except the
2165 * console if we have one.
2167 if (!uart_console(port
))
2168 uart_change_pm(state
, UART_PM_STATE_OFF
);
2172 #ifdef CONFIG_CONSOLE_POLL
2174 static int uart_poll_init(struct tty_driver
*driver
, int line
, char *options
)
2176 struct uart_driver
*drv
= driver
->driver_state
;
2177 struct uart_state
*state
= drv
->state
+ line
;
2178 struct uart_port
*port
;
2185 if (!state
|| !state
->uart_port
)
2188 port
= state
->uart_port
;
2189 if (!(port
->ops
->poll_get_char
&& port
->ops
->poll_put_char
))
2192 if (port
->ops
->poll_init
) {
2193 struct tty_port
*tport
= &state
->port
;
2196 mutex_lock(&tport
->mutex
);
2198 * We don't set ASYNCB_INITIALIZED as we only initialized the
2199 * hw, e.g. state->xmit is still uninitialized.
2201 if (!test_bit(ASYNCB_INITIALIZED
, &tport
->flags
))
2202 ret
= port
->ops
->poll_init(port
);
2203 mutex_unlock(&tport
->mutex
);
2209 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
2210 return uart_set_options(port
, NULL
, baud
, parity
, bits
, flow
);
2216 static int uart_poll_get_char(struct tty_driver
*driver
, int line
)
2218 struct uart_driver
*drv
= driver
->driver_state
;
2219 struct uart_state
*state
= drv
->state
+ line
;
2220 struct uart_port
*port
;
2222 if (!state
|| !state
->uart_port
)
2225 port
= state
->uart_port
;
2226 return port
->ops
->poll_get_char(port
);
2229 static void uart_poll_put_char(struct tty_driver
*driver
, int line
, char ch
)
2231 struct uart_driver
*drv
= driver
->driver_state
;
2232 struct uart_state
*state
= drv
->state
+ line
;
2233 struct uart_port
*port
;
2235 if (!state
|| !state
->uart_port
)
2238 port
= state
->uart_port
;
2239 port
->ops
->poll_put_char(port
, ch
);
2243 static const struct tty_operations uart_ops
= {
2245 .close
= uart_close
,
2246 .write
= uart_write
,
2247 .put_char
= uart_put_char
,
2248 .flush_chars
= uart_flush_chars
,
2249 .write_room
= uart_write_room
,
2250 .chars_in_buffer
= uart_chars_in_buffer
,
2251 .flush_buffer
= uart_flush_buffer
,
2252 .ioctl
= uart_ioctl
,
2253 .throttle
= uart_throttle
,
2254 .unthrottle
= uart_unthrottle
,
2255 .send_xchar
= uart_send_xchar
,
2256 .set_termios
= uart_set_termios
,
2257 .set_ldisc
= uart_set_ldisc
,
2259 .start
= uart_start
,
2260 .hangup
= uart_hangup
,
2261 .break_ctl
= uart_break_ctl
,
2262 .wait_until_sent
= uart_wait_until_sent
,
2263 #ifdef CONFIG_PROC_FS
2264 .proc_fops
= &uart_proc_fops
,
2266 .tiocmget
= uart_tiocmget
,
2267 .tiocmset
= uart_tiocmset
,
2268 .get_icount
= uart_get_icount
,
2269 #ifdef CONFIG_CONSOLE_POLL
2270 .poll_init
= uart_poll_init
,
2271 .poll_get_char
= uart_poll_get_char
,
2272 .poll_put_char
= uart_poll_put_char
,
2276 static const struct tty_port_operations uart_port_ops
= {
2277 .activate
= uart_port_activate
,
2278 .shutdown
= uart_port_shutdown
,
2279 .carrier_raised
= uart_carrier_raised
,
2280 .dtr_rts
= uart_dtr_rts
,
2284 * uart_register_driver - register a driver with the uart core layer
2285 * @drv: low level driver structure
2287 * Register a uart driver with the core driver. We in turn register
2288 * with the tty layer, and initialise the core driver per-port state.
2290 * We have a proc file in /proc/tty/driver which is named after the
2293 * drv->port should be NULL, and the per-port structures should be
2294 * registered using uart_add_one_port after this call has succeeded.
2296 int uart_register_driver(struct uart_driver
*drv
)
2298 struct tty_driver
*normal
;
2304 * Maybe we should be using a slab cache for this, especially if
2305 * we have a large number of ports to handle.
2307 drv
->state
= kzalloc(sizeof(struct uart_state
) * drv
->nr
, GFP_KERNEL
);
2311 normal
= alloc_tty_driver(drv
->nr
);
2315 drv
->tty_driver
= normal
;
2317 normal
->driver_name
= drv
->driver_name
;
2318 normal
->name
= drv
->dev_name
;
2319 normal
->major
= drv
->major
;
2320 normal
->minor_start
= drv
->minor
;
2321 normal
->type
= TTY_DRIVER_TYPE_SERIAL
;
2322 normal
->subtype
= SERIAL_TYPE_NORMAL
;
2323 normal
->init_termios
= tty_std_termios
;
2324 normal
->init_termios
.c_cflag
= B9600
| CS8
| CREAD
| HUPCL
| CLOCAL
;
2325 normal
->init_termios
.c_ispeed
= normal
->init_termios
.c_ospeed
= 9600;
2326 normal
->flags
= TTY_DRIVER_REAL_RAW
| TTY_DRIVER_DYNAMIC_DEV
;
2327 normal
->driver_state
= drv
;
2328 tty_set_operations(normal
, &uart_ops
);
2331 * Initialise the UART state(s).
2333 for (i
= 0; i
< drv
->nr
; i
++) {
2334 struct uart_state
*state
= drv
->state
+ i
;
2335 struct tty_port
*port
= &state
->port
;
2337 tty_port_init(port
);
2338 port
->ops
= &uart_port_ops
;
2339 port
->close_delay
= HZ
/ 2; /* .5 seconds */
2340 port
->closing_wait
= 30 * HZ
;/* 30 seconds */
2343 retval
= tty_register_driver(normal
);
2347 for (i
= 0; i
< drv
->nr
; i
++)
2348 tty_port_destroy(&drv
->state
[i
].port
);
2349 put_tty_driver(normal
);
2357 * uart_unregister_driver - remove a driver from the uart core layer
2358 * @drv: low level driver structure
2360 * Remove all references to a driver from the core driver. The low
2361 * level driver must have removed all its ports via the
2362 * uart_remove_one_port() if it registered them with uart_add_one_port().
2363 * (ie, drv->port == NULL)
2365 void uart_unregister_driver(struct uart_driver
*drv
)
2367 struct tty_driver
*p
= drv
->tty_driver
;
2370 tty_unregister_driver(p
);
2372 for (i
= 0; i
< drv
->nr
; i
++)
2373 tty_port_destroy(&drv
->state
[i
].port
);
2376 drv
->tty_driver
= NULL
;
2379 struct tty_driver
*uart_console_device(struct console
*co
, int *index
)
2381 struct uart_driver
*p
= co
->data
;
2383 return p
->tty_driver
;
2386 static ssize_t
uart_get_attr_uartclk(struct device
*dev
,
2387 struct device_attribute
*attr
, char *buf
)
2389 struct serial_struct tmp
;
2390 struct tty_port
*port
= dev_get_drvdata(dev
);
2392 uart_get_info(port
, &tmp
);
2393 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.baud_base
* 16);
2396 static ssize_t
uart_get_attr_type(struct device
*dev
,
2397 struct device_attribute
*attr
, char *buf
)
2399 struct serial_struct tmp
;
2400 struct tty_port
*port
= dev_get_drvdata(dev
);
2402 uart_get_info(port
, &tmp
);
2403 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.type
);
2405 static ssize_t
uart_get_attr_line(struct device
*dev
,
2406 struct device_attribute
*attr
, char *buf
)
2408 struct serial_struct tmp
;
2409 struct tty_port
*port
= dev_get_drvdata(dev
);
2411 uart_get_info(port
, &tmp
);
2412 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.line
);
2415 static ssize_t
uart_get_attr_port(struct device
*dev
,
2416 struct device_attribute
*attr
, char *buf
)
2418 struct serial_struct tmp
;
2419 struct tty_port
*port
= dev_get_drvdata(dev
);
2420 unsigned long ioaddr
;
2422 uart_get_info(port
, &tmp
);
2424 if (HIGH_BITS_OFFSET
)
2425 ioaddr
|= (unsigned long)tmp
.port_high
<< HIGH_BITS_OFFSET
;
2426 return snprintf(buf
, PAGE_SIZE
, "0x%lX\n", ioaddr
);
2429 static ssize_t
uart_get_attr_irq(struct device
*dev
,
2430 struct device_attribute
*attr
, char *buf
)
2432 struct serial_struct tmp
;
2433 struct tty_port
*port
= dev_get_drvdata(dev
);
2435 uart_get_info(port
, &tmp
);
2436 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.irq
);
2439 static ssize_t
uart_get_attr_flags(struct device
*dev
,
2440 struct device_attribute
*attr
, char *buf
)
2442 struct serial_struct tmp
;
2443 struct tty_port
*port
= dev_get_drvdata(dev
);
2445 uart_get_info(port
, &tmp
);
2446 return snprintf(buf
, PAGE_SIZE
, "0x%X\n", tmp
.flags
);
2449 static ssize_t
uart_get_attr_xmit_fifo_size(struct device
*dev
,
2450 struct device_attribute
*attr
, char *buf
)
2452 struct serial_struct tmp
;
2453 struct tty_port
*port
= dev_get_drvdata(dev
);
2455 uart_get_info(port
, &tmp
);
2456 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.xmit_fifo_size
);
2460 static ssize_t
uart_get_attr_close_delay(struct device
*dev
,
2461 struct device_attribute
*attr
, char *buf
)
2463 struct serial_struct tmp
;
2464 struct tty_port
*port
= dev_get_drvdata(dev
);
2466 uart_get_info(port
, &tmp
);
2467 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.close_delay
);
2471 static ssize_t
uart_get_attr_closing_wait(struct device
*dev
,
2472 struct device_attribute
*attr
, char *buf
)
2474 struct serial_struct tmp
;
2475 struct tty_port
*port
= dev_get_drvdata(dev
);
2477 uart_get_info(port
, &tmp
);
2478 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.closing_wait
);
2481 static ssize_t
uart_get_attr_custom_divisor(struct device
*dev
,
2482 struct device_attribute
*attr
, char *buf
)
2484 struct serial_struct tmp
;
2485 struct tty_port
*port
= dev_get_drvdata(dev
);
2487 uart_get_info(port
, &tmp
);
2488 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.custom_divisor
);
2491 static ssize_t
uart_get_attr_io_type(struct device
*dev
,
2492 struct device_attribute
*attr
, char *buf
)
2494 struct serial_struct tmp
;
2495 struct tty_port
*port
= dev_get_drvdata(dev
);
2497 uart_get_info(port
, &tmp
);
2498 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.io_type
);
2501 static ssize_t
uart_get_attr_iomem_base(struct device
*dev
,
2502 struct device_attribute
*attr
, char *buf
)
2504 struct serial_struct tmp
;
2505 struct tty_port
*port
= dev_get_drvdata(dev
);
2507 uart_get_info(port
, &tmp
);
2508 return snprintf(buf
, PAGE_SIZE
, "0x%lX\n", (unsigned long)tmp
.iomem_base
);
2511 static ssize_t
uart_get_attr_iomem_reg_shift(struct device
*dev
,
2512 struct device_attribute
*attr
, char *buf
)
2514 struct serial_struct tmp
;
2515 struct tty_port
*port
= dev_get_drvdata(dev
);
2517 uart_get_info(port
, &tmp
);
2518 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.iomem_reg_shift
);
2521 static DEVICE_ATTR(type
, S_IRUSR
| S_IRGRP
, uart_get_attr_type
, NULL
);
2522 static DEVICE_ATTR(line
, S_IRUSR
| S_IRGRP
, uart_get_attr_line
, NULL
);
2523 static DEVICE_ATTR(port
, S_IRUSR
| S_IRGRP
, uart_get_attr_port
, NULL
);
2524 static DEVICE_ATTR(irq
, S_IRUSR
| S_IRGRP
, uart_get_attr_irq
, NULL
);
2525 static DEVICE_ATTR(flags
, S_IRUSR
| S_IRGRP
, uart_get_attr_flags
, NULL
);
2526 static DEVICE_ATTR(xmit_fifo_size
, S_IRUSR
| S_IRGRP
, uart_get_attr_xmit_fifo_size
, NULL
);
2527 static DEVICE_ATTR(uartclk
, S_IRUSR
| S_IRGRP
, uart_get_attr_uartclk
, NULL
);
2528 static DEVICE_ATTR(close_delay
, S_IRUSR
| S_IRGRP
, uart_get_attr_close_delay
, NULL
);
2529 static DEVICE_ATTR(closing_wait
, S_IRUSR
| S_IRGRP
, uart_get_attr_closing_wait
, NULL
);
2530 static DEVICE_ATTR(custom_divisor
, S_IRUSR
| S_IRGRP
, uart_get_attr_custom_divisor
, NULL
);
2531 static DEVICE_ATTR(io_type
, S_IRUSR
| S_IRGRP
, uart_get_attr_io_type
, NULL
);
2532 static DEVICE_ATTR(iomem_base
, S_IRUSR
| S_IRGRP
, uart_get_attr_iomem_base
, NULL
);
2533 static DEVICE_ATTR(iomem_reg_shift
, S_IRUSR
| S_IRGRP
, uart_get_attr_iomem_reg_shift
, NULL
);
2535 static struct attribute
*tty_dev_attrs
[] = {
2536 &dev_attr_type
.attr
,
2537 &dev_attr_line
.attr
,
2538 &dev_attr_port
.attr
,
2540 &dev_attr_flags
.attr
,
2541 &dev_attr_xmit_fifo_size
.attr
,
2542 &dev_attr_uartclk
.attr
,
2543 &dev_attr_close_delay
.attr
,
2544 &dev_attr_closing_wait
.attr
,
2545 &dev_attr_custom_divisor
.attr
,
2546 &dev_attr_io_type
.attr
,
2547 &dev_attr_iomem_base
.attr
,
2548 &dev_attr_iomem_reg_shift
.attr
,
2552 static const struct attribute_group tty_dev_attr_group
= {
2553 .attrs
= tty_dev_attrs
,
2556 static const struct attribute_group
*tty_dev_attr_groups
[] = {
2557 &tty_dev_attr_group
,
2563 * uart_add_one_port - attach a driver-defined port structure
2564 * @drv: pointer to the uart low level driver structure for this port
2565 * @uport: uart port structure to use for this port.
2567 * This allows the driver to register its own uart_port structure
2568 * with the core driver. The main purpose is to allow the low
2569 * level uart drivers to expand uart_port, rather than having yet
2570 * more levels of structures.
2572 int uart_add_one_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2574 struct uart_state
*state
;
2575 struct tty_port
*port
;
2577 struct device
*tty_dev
;
2579 BUG_ON(in_interrupt());
2581 if (uport
->line
>= drv
->nr
)
2584 state
= drv
->state
+ uport
->line
;
2585 port
= &state
->port
;
2587 mutex_lock(&port_mutex
);
2588 mutex_lock(&port
->mutex
);
2589 if (state
->uart_port
) {
2594 state
->uart_port
= uport
;
2595 state
->pm_state
= UART_PM_STATE_UNDEFINED
;
2597 uport
->cons
= drv
->cons
;
2598 uport
->state
= state
;
2601 * If this port is a console, then the spinlock is already
2604 if (!(uart_console(uport
) && (uport
->cons
->flags
& CON_ENABLED
))) {
2605 spin_lock_init(&uport
->lock
);
2606 lockdep_set_class(&uport
->lock
, &port_lock_key
);
2609 uart_configure_port(drv
, state
, uport
);
2612 * Register the port whether it's detected or not. This allows
2613 * setserial to be used to alter this port's parameters.
2615 tty_dev
= tty_port_register_device_attr(port
, drv
->tty_driver
,
2616 uport
->line
, uport
->dev
, port
, tty_dev_attr_groups
);
2617 if (likely(!IS_ERR(tty_dev
))) {
2618 device_set_wakeup_capable(tty_dev
, 1);
2620 printk(KERN_ERR
"Cannot register tty device on line %d\n",
2625 * Ensure UPF_DEAD is not set.
2627 uport
->flags
&= ~UPF_DEAD
;
2630 mutex_unlock(&port
->mutex
);
2631 mutex_unlock(&port_mutex
);
2637 * uart_remove_one_port - detach a driver defined port structure
2638 * @drv: pointer to the uart low level driver structure for this port
2639 * @uport: uart port structure for this port
2641 * This unhooks (and hangs up) the specified port structure from the
2642 * core driver. No further calls will be made to the low-level code
2645 int uart_remove_one_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2647 struct uart_state
*state
= drv
->state
+ uport
->line
;
2648 struct tty_port
*port
= &state
->port
;
2649 struct tty_struct
*tty
;
2652 BUG_ON(in_interrupt());
2654 if (state
->uart_port
!= uport
)
2655 printk(KERN_ALERT
"Removing wrong port: %p != %p\n",
2656 state
->uart_port
, uport
);
2658 mutex_lock(&port_mutex
);
2661 * Mark the port "dead" - this prevents any opens from
2662 * succeeding while we shut down the port.
2664 mutex_lock(&port
->mutex
);
2665 if (!state
->uart_port
) {
2666 mutex_unlock(&port
->mutex
);
2670 uport
->flags
|= UPF_DEAD
;
2671 mutex_unlock(&port
->mutex
);
2674 * Remove the devices from the tty layer
2676 tty_unregister_device(drv
->tty_driver
, uport
->line
);
2678 tty
= tty_port_tty_get(port
);
2680 tty_vhangup(port
->tty
);
2685 * If the port is used as a console, unregister it
2687 if (uart_console(uport
))
2688 unregister_console(uport
->cons
);
2691 * Free the port IO and memory resources, if any.
2693 if (uport
->type
!= PORT_UNKNOWN
)
2694 uport
->ops
->release_port(uport
);
2697 * Indicate that there isn't a port here anymore.
2699 uport
->type
= PORT_UNKNOWN
;
2701 state
->uart_port
= NULL
;
2703 mutex_unlock(&port_mutex
);
2709 * Are the two ports equivalent?
2711 int uart_match_port(struct uart_port
*port1
, struct uart_port
*port2
)
2713 if (port1
->iotype
!= port2
->iotype
)
2716 switch (port1
->iotype
) {
2718 return (port1
->iobase
== port2
->iobase
);
2720 return (port1
->iobase
== port2
->iobase
) &&
2721 (port1
->hub6
== port2
->hub6
);
2726 return (port1
->mapbase
== port2
->mapbase
);
2730 EXPORT_SYMBOL(uart_match_port
);
2733 * uart_handle_dcd_change - handle a change of carrier detect state
2734 * @uport: uart_port structure for the open port
2735 * @status: new carrier detect status, nonzero if active
2737 void uart_handle_dcd_change(struct uart_port
*uport
, unsigned int status
)
2739 struct tty_port
*port
= &uport
->state
->port
;
2740 struct tty_struct
*tty
= port
->tty
;
2741 struct tty_ldisc
*ld
= tty
? tty_ldisc_ref(tty
) : NULL
;
2744 if (ld
->ops
->dcd_change
)
2745 ld
->ops
->dcd_change(tty
, status
);
2746 tty_ldisc_deref(ld
);
2749 uport
->icount
.dcd
++;
2751 if (port
->flags
& ASYNC_CHECK_CD
) {
2753 wake_up_interruptible(&port
->open_wait
);
2758 EXPORT_SYMBOL_GPL(uart_handle_dcd_change
);
2761 * uart_handle_cts_change - handle a change of clear-to-send state
2762 * @uport: uart_port structure for the open port
2763 * @status: new clear to send status, nonzero if active
2765 void uart_handle_cts_change(struct uart_port
*uport
, unsigned int status
)
2767 struct tty_port
*port
= &uport
->state
->port
;
2768 struct tty_struct
*tty
= port
->tty
;
2770 uport
->icount
.cts
++;
2772 if (tty_port_cts_enabled(port
)) {
2773 if (tty
->hw_stopped
) {
2775 tty
->hw_stopped
= 0;
2776 uport
->ops
->start_tx(uport
);
2777 uart_write_wakeup(uport
);
2781 tty
->hw_stopped
= 1;
2782 uport
->ops
->stop_tx(uport
);
2787 EXPORT_SYMBOL_GPL(uart_handle_cts_change
);
2790 * uart_insert_char - push a char to the uart layer
2792 * User is responsible to call tty_flip_buffer_push when they are done with
2795 * @port: corresponding port
2796 * @status: state of the serial port RX buffer (LSR for 8250)
2797 * @overrun: mask of overrun bits in @status
2798 * @ch: character to push
2799 * @flag: flag for the character (see TTY_NORMAL and friends)
2801 void uart_insert_char(struct uart_port
*port
, unsigned int status
,
2802 unsigned int overrun
, unsigned int ch
, unsigned int flag
)
2804 struct tty_port
*tport
= &port
->state
->port
;
2806 if ((status
& port
->ignore_status_mask
& ~overrun
) == 0)
2807 if (tty_insert_flip_char(tport
, ch
, flag
) == 0)
2808 ++port
->icount
.buf_overrun
;
2811 * Overrun is special. Since it's reported immediately,
2812 * it doesn't affect the current character.
2814 if (status
& ~port
->ignore_status_mask
& overrun
)
2815 if (tty_insert_flip_char(tport
, 0, TTY_OVERRUN
) == 0)
2816 ++port
->icount
.buf_overrun
;
2818 EXPORT_SYMBOL_GPL(uart_insert_char
);
2820 EXPORT_SYMBOL(uart_write_wakeup
);
2821 EXPORT_SYMBOL(uart_register_driver
);
2822 EXPORT_SYMBOL(uart_unregister_driver
);
2823 EXPORT_SYMBOL(uart_suspend_port
);
2824 EXPORT_SYMBOL(uart_resume_port
);
2825 EXPORT_SYMBOL(uart_add_one_port
);
2826 EXPORT_SYMBOL(uart_remove_one_port
);
2828 MODULE_DESCRIPTION("Serial driver core");
2829 MODULE_LICENSE("GPL");