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 * Make sure the device is in D0 state.
142 uart_change_pm(state
, UART_PM_STATE_ON
);
145 * Initialise and allocate the transmit and temporary
148 if (!state
->xmit
.buf
) {
149 /* This is protected by the per port mutex */
150 page
= get_zeroed_page(GFP_KERNEL
);
154 state
->xmit
.buf
= (unsigned char *) page
;
155 uart_circ_clear(&state
->xmit
);
158 retval
= uport
->ops
->startup(uport
);
160 if (uart_console(uport
) && uport
->cons
->cflag
) {
161 tty
->termios
.c_cflag
= uport
->cons
->cflag
;
162 uport
->cons
->cflag
= 0;
165 * Initialise the hardware port settings.
167 uart_change_speed(tty
, state
, NULL
);
171 * Setup the RTS and DTR signals once the
172 * port is open and ready to respond.
174 if (tty
->termios
.c_cflag
& CBAUD
)
175 uart_set_mctrl(uport
, TIOCM_RTS
| TIOCM_DTR
);
178 * if hw support flow control without software intervention,
179 * then skip the below check
181 if (tty_port_cts_enabled(port
) &&
182 !(uport
->flags
& UPF_HARD_FLOW
)) {
183 spin_lock_irq(&uport
->lock
);
184 if (!(uport
->ops
->get_mctrl(uport
) & TIOCM_CTS
))
186 spin_unlock_irq(&uport
->lock
);
191 * This is to allow setserial on this port. People may want to set
192 * port/irq/type and then reconfigure the port properly if it failed
195 if (retval
&& capable(CAP_SYS_ADMIN
))
201 static int uart_startup(struct tty_struct
*tty
, struct uart_state
*state
,
204 struct tty_port
*port
= &state
->port
;
207 if (port
->flags
& ASYNC_INITIALIZED
)
211 * Set the TTY IO error marker - we will only clear this
212 * once we have successfully opened the port.
214 set_bit(TTY_IO_ERROR
, &tty
->flags
);
216 retval
= uart_port_startup(tty
, state
, init_hw
);
218 set_bit(ASYNCB_INITIALIZED
, &port
->flags
);
219 clear_bit(TTY_IO_ERROR
, &tty
->flags
);
220 } else if (retval
> 0)
227 * This routine will shutdown a serial port; interrupts are disabled, and
228 * DTR is dropped if the hangup on close termio flag is on. Calls to
229 * uart_shutdown are serialised by the per-port semaphore.
231 static void uart_shutdown(struct tty_struct
*tty
, struct uart_state
*state
)
233 struct uart_port
*uport
= state
->uart_port
;
234 struct tty_port
*port
= &state
->port
;
237 * Set the TTY IO error marker
240 set_bit(TTY_IO_ERROR
, &tty
->flags
);
242 if (test_and_clear_bit(ASYNCB_INITIALIZED
, &port
->flags
)) {
244 * Turn off DTR and RTS early.
246 if (!tty
|| (tty
->termios
.c_cflag
& HUPCL
))
247 uart_clear_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
249 uart_port_shutdown(port
);
253 * It's possible for shutdown to be called after suspend if we get
254 * a DCD drop (hangup) at just the right time. Clear suspended bit so
255 * we don't try to resume a port that has been shutdown.
257 clear_bit(ASYNCB_SUSPENDED
, &port
->flags
);
260 * Free the transmit buffer page.
262 if (state
->xmit
.buf
) {
263 free_page((unsigned long)state
->xmit
.buf
);
264 state
->xmit
.buf
= NULL
;
269 * uart_update_timeout - update per-port FIFO timeout.
270 * @port: uart_port structure describing the port
271 * @cflag: termios cflag value
272 * @baud: speed of the port
274 * Set the port FIFO timeout value. The @cflag value should
275 * reflect the actual hardware settings.
278 uart_update_timeout(struct uart_port
*port
, unsigned int cflag
,
283 /* byte size and parity */
284 switch (cflag
& CSIZE
) {
305 * The total number of bits to be transmitted in the fifo.
307 bits
= bits
* port
->fifosize
;
310 * Figure the timeout to send the above number of bits.
311 * Add .02 seconds of slop
313 port
->timeout
= (HZ
* bits
) / baud
+ HZ
/50;
316 EXPORT_SYMBOL(uart_update_timeout
);
319 * uart_get_baud_rate - return baud rate for a particular port
320 * @port: uart_port structure describing the port in question.
321 * @termios: desired termios settings.
322 * @old: old termios (or NULL)
323 * @min: minimum acceptable baud rate
324 * @max: maximum acceptable baud rate
326 * Decode the termios structure into a numeric baud rate,
327 * taking account of the magic 38400 baud rate (with spd_*
328 * flags), and mapping the %B0 rate to 9600 baud.
330 * If the new baud rate is invalid, try the old termios setting.
331 * If it's still invalid, we try 9600 baud.
333 * Update the @termios structure to reflect the baud rate
334 * we're actually going to be using. Don't do this for the case
335 * where B0 is requested ("hang up").
338 uart_get_baud_rate(struct uart_port
*port
, struct ktermios
*termios
,
339 struct ktermios
*old
, unsigned int min
, unsigned int max
)
341 unsigned int try, baud
, altbaud
= 38400;
343 upf_t flags
= port
->flags
& UPF_SPD_MASK
;
345 if (flags
== UPF_SPD_HI
)
347 else if (flags
== UPF_SPD_VHI
)
349 else if (flags
== UPF_SPD_SHI
)
351 else if (flags
== UPF_SPD_WARP
)
354 for (try = 0; try < 2; try++) {
355 baud
= tty_termios_baud_rate(termios
);
358 * The spd_hi, spd_vhi, spd_shi, spd_warp kludge...
365 * Special case: B0 rate.
372 if (baud
>= min
&& baud
<= max
)
376 * Oops, the quotient was zero. Try again with
377 * the old baud rate if possible.
379 termios
->c_cflag
&= ~CBAUD
;
381 baud
= tty_termios_baud_rate(old
);
383 tty_termios_encode_baud_rate(termios
,
390 * As a last resort, if the range cannot be met then clip to
391 * the nearest chip supported rate.
395 tty_termios_encode_baud_rate(termios
,
398 tty_termios_encode_baud_rate(termios
,
402 /* Should never happen */
407 EXPORT_SYMBOL(uart_get_baud_rate
);
410 * uart_get_divisor - return uart clock divisor
411 * @port: uart_port structure describing the port.
412 * @baud: desired baud rate
414 * Calculate the uart clock divisor for the port.
417 uart_get_divisor(struct uart_port
*port
, unsigned int baud
)
422 * Old custom speed handling.
424 if (baud
== 38400 && (port
->flags
& UPF_SPD_MASK
) == UPF_SPD_CUST
)
425 quot
= port
->custom_divisor
;
427 quot
= DIV_ROUND_CLOSEST(port
->uartclk
, 16 * baud
);
432 EXPORT_SYMBOL(uart_get_divisor
);
434 /* FIXME: Consistent locking policy */
435 static void uart_change_speed(struct tty_struct
*tty
, struct uart_state
*state
,
436 struct ktermios
*old_termios
)
438 struct tty_port
*port
= &state
->port
;
439 struct uart_port
*uport
= state
->uart_port
;
440 struct ktermios
*termios
;
443 * If we have no tty, termios, or the port does not exist,
444 * then we can't set the parameters for this port.
446 if (!tty
|| uport
->type
== PORT_UNKNOWN
)
449 termios
= &tty
->termios
;
452 * Set flags based on termios cflag
454 if (termios
->c_cflag
& CRTSCTS
)
455 set_bit(ASYNCB_CTS_FLOW
, &port
->flags
);
457 clear_bit(ASYNCB_CTS_FLOW
, &port
->flags
);
459 if (termios
->c_cflag
& CLOCAL
)
460 clear_bit(ASYNCB_CHECK_CD
, &port
->flags
);
462 set_bit(ASYNCB_CHECK_CD
, &port
->flags
);
464 uport
->ops
->set_termios(uport
, termios
, old_termios
);
467 static inline int __uart_put_char(struct uart_port
*port
,
468 struct circ_buf
*circ
, unsigned char c
)
476 spin_lock_irqsave(&port
->lock
, flags
);
477 if (uart_circ_chars_free(circ
) != 0) {
478 circ
->buf
[circ
->head
] = c
;
479 circ
->head
= (circ
->head
+ 1) & (UART_XMIT_SIZE
- 1);
482 spin_unlock_irqrestore(&port
->lock
, flags
);
486 static int uart_put_char(struct tty_struct
*tty
, unsigned char ch
)
488 struct uart_state
*state
= tty
->driver_data
;
490 return __uart_put_char(state
->uart_port
, &state
->xmit
, ch
);
493 static void uart_flush_chars(struct tty_struct
*tty
)
498 static int uart_write(struct tty_struct
*tty
,
499 const unsigned char *buf
, int count
)
501 struct uart_state
*state
= tty
->driver_data
;
502 struct uart_port
*port
;
503 struct circ_buf
*circ
;
508 * This means you called this function _after_ the port was
509 * closed. No cookie for you.
516 port
= state
->uart_port
;
522 spin_lock_irqsave(&port
->lock
, flags
);
524 c
= CIRC_SPACE_TO_END(circ
->head
, circ
->tail
, UART_XMIT_SIZE
);
529 memcpy(circ
->buf
+ circ
->head
, buf
, c
);
530 circ
->head
= (circ
->head
+ c
) & (UART_XMIT_SIZE
- 1);
535 spin_unlock_irqrestore(&port
->lock
, flags
);
541 static int uart_write_room(struct tty_struct
*tty
)
543 struct uart_state
*state
= tty
->driver_data
;
547 spin_lock_irqsave(&state
->uart_port
->lock
, flags
);
548 ret
= uart_circ_chars_free(&state
->xmit
);
549 spin_unlock_irqrestore(&state
->uart_port
->lock
, flags
);
553 static int uart_chars_in_buffer(struct tty_struct
*tty
)
555 struct uart_state
*state
= tty
->driver_data
;
559 spin_lock_irqsave(&state
->uart_port
->lock
, flags
);
560 ret
= uart_circ_chars_pending(&state
->xmit
);
561 spin_unlock_irqrestore(&state
->uart_port
->lock
, flags
);
565 static void uart_flush_buffer(struct tty_struct
*tty
)
567 struct uart_state
*state
= tty
->driver_data
;
568 struct uart_port
*port
;
572 * This means you called this function _after_ the port was
573 * closed. No cookie for you.
580 port
= state
->uart_port
;
581 pr_debug("uart_flush_buffer(%d) called\n", tty
->index
);
583 spin_lock_irqsave(&port
->lock
, flags
);
584 uart_circ_clear(&state
->xmit
);
585 if (port
->ops
->flush_buffer
)
586 port
->ops
->flush_buffer(port
);
587 spin_unlock_irqrestore(&port
->lock
, flags
);
592 * This function is used to send a high-priority XON/XOFF character to
595 static void uart_send_xchar(struct tty_struct
*tty
, char ch
)
597 struct uart_state
*state
= tty
->driver_data
;
598 struct uart_port
*port
= state
->uart_port
;
601 if (port
->ops
->send_xchar
)
602 port
->ops
->send_xchar(port
, ch
);
606 spin_lock_irqsave(&port
->lock
, flags
);
607 port
->ops
->start_tx(port
);
608 spin_unlock_irqrestore(&port
->lock
, flags
);
613 static void uart_throttle(struct tty_struct
*tty
)
615 struct uart_state
*state
= tty
->driver_data
;
616 struct uart_port
*port
= state
->uart_port
;
620 mask
|= UPF_SOFT_FLOW
;
621 if (tty
->termios
.c_cflag
& CRTSCTS
)
622 mask
|= UPF_HARD_FLOW
;
624 if (port
->flags
& mask
) {
625 port
->ops
->throttle(port
);
626 mask
&= ~port
->flags
;
629 if (mask
& UPF_SOFT_FLOW
)
630 uart_send_xchar(tty
, STOP_CHAR(tty
));
632 if (mask
& UPF_HARD_FLOW
)
633 uart_clear_mctrl(port
, TIOCM_RTS
);
636 static void uart_unthrottle(struct tty_struct
*tty
)
638 struct uart_state
*state
= tty
->driver_data
;
639 struct uart_port
*port
= state
->uart_port
;
643 mask
|= UPF_SOFT_FLOW
;
644 if (tty
->termios
.c_cflag
& CRTSCTS
)
645 mask
|= UPF_HARD_FLOW
;
647 if (port
->flags
& mask
) {
648 port
->ops
->unthrottle(port
);
649 mask
&= ~port
->flags
;
652 if (mask
& UPF_SOFT_FLOW
) {
656 uart_send_xchar(tty
, START_CHAR(tty
));
659 if (mask
& UPF_HARD_FLOW
)
660 uart_set_mctrl(port
, TIOCM_RTS
);
663 static void do_uart_get_info(struct tty_port
*port
,
664 struct serial_struct
*retinfo
)
666 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
667 struct uart_port
*uport
= state
->uart_port
;
669 memset(retinfo
, 0, sizeof(*retinfo
));
671 retinfo
->type
= uport
->type
;
672 retinfo
->line
= uport
->line
;
673 retinfo
->port
= uport
->iobase
;
674 if (HIGH_BITS_OFFSET
)
675 retinfo
->port_high
= (long) uport
->iobase
>> HIGH_BITS_OFFSET
;
676 retinfo
->irq
= uport
->irq
;
677 retinfo
->flags
= uport
->flags
;
678 retinfo
->xmit_fifo_size
= uport
->fifosize
;
679 retinfo
->baud_base
= uport
->uartclk
/ 16;
680 retinfo
->close_delay
= jiffies_to_msecs(port
->close_delay
) / 10;
681 retinfo
->closing_wait
= port
->closing_wait
== ASYNC_CLOSING_WAIT_NONE
?
682 ASYNC_CLOSING_WAIT_NONE
:
683 jiffies_to_msecs(port
->closing_wait
) / 10;
684 retinfo
->custom_divisor
= uport
->custom_divisor
;
685 retinfo
->hub6
= uport
->hub6
;
686 retinfo
->io_type
= uport
->iotype
;
687 retinfo
->iomem_reg_shift
= uport
->regshift
;
688 retinfo
->iomem_base
= (void *)(unsigned long)uport
->mapbase
;
691 static void uart_get_info(struct tty_port
*port
,
692 struct serial_struct
*retinfo
)
694 /* Ensure the state we copy is consistent and no hardware changes
696 mutex_lock(&port
->mutex
);
697 do_uart_get_info(port
, retinfo
);
698 mutex_unlock(&port
->mutex
);
701 static int uart_get_info_user(struct tty_port
*port
,
702 struct serial_struct __user
*retinfo
)
704 struct serial_struct tmp
;
705 uart_get_info(port
, &tmp
);
707 if (copy_to_user(retinfo
, &tmp
, sizeof(*retinfo
)))
712 static int uart_set_info(struct tty_struct
*tty
, struct tty_port
*port
,
713 struct uart_state
*state
,
714 struct serial_struct
*new_info
)
716 struct uart_port
*uport
= state
->uart_port
;
717 unsigned long new_port
;
718 unsigned int change_irq
, change_port
, closing_wait
;
719 unsigned int old_custom_divisor
, close_delay
;
720 upf_t old_flags
, new_flags
;
723 new_port
= new_info
->port
;
724 if (HIGH_BITS_OFFSET
)
725 new_port
+= (unsigned long) new_info
->port_high
<< HIGH_BITS_OFFSET
;
727 new_info
->irq
= irq_canonicalize(new_info
->irq
);
728 close_delay
= msecs_to_jiffies(new_info
->close_delay
* 10);
729 closing_wait
= new_info
->closing_wait
== ASYNC_CLOSING_WAIT_NONE
?
730 ASYNC_CLOSING_WAIT_NONE
:
731 msecs_to_jiffies(new_info
->closing_wait
* 10);
734 change_irq
= !(uport
->flags
& UPF_FIXED_PORT
)
735 && new_info
->irq
!= uport
->irq
;
738 * Since changing the 'type' of the port changes its resource
739 * allocations, we should treat type changes the same as
742 change_port
= !(uport
->flags
& UPF_FIXED_PORT
)
743 && (new_port
!= uport
->iobase
||
744 (unsigned long)new_info
->iomem_base
!= uport
->mapbase
||
745 new_info
->hub6
!= uport
->hub6
||
746 new_info
->io_type
!= uport
->iotype
||
747 new_info
->iomem_reg_shift
!= uport
->regshift
||
748 new_info
->type
!= uport
->type
);
750 old_flags
= uport
->flags
;
751 new_flags
= new_info
->flags
;
752 old_custom_divisor
= uport
->custom_divisor
;
754 if (!capable(CAP_SYS_ADMIN
)) {
756 if (change_irq
|| change_port
||
757 (new_info
->baud_base
!= uport
->uartclk
/ 16) ||
758 (close_delay
!= port
->close_delay
) ||
759 (closing_wait
!= port
->closing_wait
) ||
760 (new_info
->xmit_fifo_size
&&
761 new_info
->xmit_fifo_size
!= uport
->fifosize
) ||
762 (((new_flags
^ old_flags
) & ~UPF_USR_MASK
) != 0))
764 uport
->flags
= ((uport
->flags
& ~UPF_USR_MASK
) |
765 (new_flags
& UPF_USR_MASK
));
766 uport
->custom_divisor
= new_info
->custom_divisor
;
771 * Ask the low level driver to verify the settings.
773 if (uport
->ops
->verify_port
)
774 retval
= uport
->ops
->verify_port(uport
, new_info
);
776 if ((new_info
->irq
>= nr_irqs
) || (new_info
->irq
< 0) ||
777 (new_info
->baud_base
< 9600))
783 if (change_port
|| change_irq
) {
787 * Make sure that we are the sole user of this port.
789 if (tty_port_users(port
) > 1)
793 * We need to shutdown the serial port at the old
794 * port/type/irq combination.
796 uart_shutdown(tty
, state
);
800 unsigned long old_iobase
, old_mapbase
;
801 unsigned int old_type
, old_iotype
, old_hub6
, old_shift
;
803 old_iobase
= uport
->iobase
;
804 old_mapbase
= uport
->mapbase
;
805 old_type
= uport
->type
;
806 old_hub6
= uport
->hub6
;
807 old_iotype
= uport
->iotype
;
808 old_shift
= uport
->regshift
;
811 * Free and release old regions
813 if (old_type
!= PORT_UNKNOWN
)
814 uport
->ops
->release_port(uport
);
816 uport
->iobase
= new_port
;
817 uport
->type
= new_info
->type
;
818 uport
->hub6
= new_info
->hub6
;
819 uport
->iotype
= new_info
->io_type
;
820 uport
->regshift
= new_info
->iomem_reg_shift
;
821 uport
->mapbase
= (unsigned long)new_info
->iomem_base
;
824 * Claim and map the new regions
826 if (uport
->type
!= PORT_UNKNOWN
) {
827 retval
= uport
->ops
->request_port(uport
);
829 /* Always success - Jean II */
834 * If we fail to request resources for the
835 * new port, try to restore the old settings.
838 uport
->iobase
= old_iobase
;
839 uport
->type
= old_type
;
840 uport
->hub6
= old_hub6
;
841 uport
->iotype
= old_iotype
;
842 uport
->regshift
= old_shift
;
843 uport
->mapbase
= old_mapbase
;
845 if (old_type
!= PORT_UNKNOWN
) {
846 retval
= uport
->ops
->request_port(uport
);
848 * If we failed to restore the old settings,
852 uport
->type
= PORT_UNKNOWN
;
860 /* Added to return the correct error -Ram Gupta */
866 uport
->irq
= new_info
->irq
;
867 if (!(uport
->flags
& UPF_FIXED_PORT
))
868 uport
->uartclk
= new_info
->baud_base
* 16;
869 uport
->flags
= (uport
->flags
& ~UPF_CHANGE_MASK
) |
870 (new_flags
& UPF_CHANGE_MASK
);
871 uport
->custom_divisor
= new_info
->custom_divisor
;
872 port
->close_delay
= close_delay
;
873 port
->closing_wait
= closing_wait
;
874 if (new_info
->xmit_fifo_size
)
875 uport
->fifosize
= new_info
->xmit_fifo_size
;
876 port
->low_latency
= (uport
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
880 if (uport
->type
== PORT_UNKNOWN
)
882 if (port
->flags
& ASYNC_INITIALIZED
) {
883 if (((old_flags
^ uport
->flags
) & UPF_SPD_MASK
) ||
884 old_custom_divisor
!= uport
->custom_divisor
) {
886 * If they're setting up a custom divisor or speed,
887 * instead of clearing it, then bitch about it. No
888 * need to rate-limit; it's CAP_SYS_ADMIN only.
890 if (uport
->flags
& UPF_SPD_MASK
) {
893 "%s sets custom speed on %s. This "
894 "is deprecated.\n", current
->comm
,
895 tty_name(port
->tty
, buf
));
897 uart_change_speed(tty
, state
, NULL
);
900 retval
= uart_startup(tty
, state
, 1);
905 static int uart_set_info_user(struct tty_struct
*tty
, struct uart_state
*state
,
906 struct serial_struct __user
*newinfo
)
908 struct serial_struct new_serial
;
909 struct tty_port
*port
= &state
->port
;
912 if (copy_from_user(&new_serial
, newinfo
, sizeof(new_serial
)))
916 * This semaphore protects port->count. It is also
917 * very useful to prevent opens. Also, take the
918 * port configuration semaphore to make sure that a
919 * module insertion/removal doesn't change anything
922 mutex_lock(&port
->mutex
);
923 retval
= uart_set_info(tty
, port
, state
, &new_serial
);
924 mutex_unlock(&port
->mutex
);
929 * uart_get_lsr_info - get line status register info
930 * @tty: tty associated with the UART
931 * @state: UART being queried
932 * @value: returned modem value
934 * Note: uart_ioctl protects us against hangups.
936 static int uart_get_lsr_info(struct tty_struct
*tty
,
937 struct uart_state
*state
, unsigned int __user
*value
)
939 struct uart_port
*uport
= state
->uart_port
;
942 result
= uport
->ops
->tx_empty(uport
);
945 * If we're about to load something into the transmit
946 * register, we'll pretend the transmitter isn't empty to
947 * avoid a race condition (depending on when the transmit
948 * interrupt happens).
951 ((uart_circ_chars_pending(&state
->xmit
) > 0) &&
952 !tty
->stopped
&& !tty
->hw_stopped
))
953 result
&= ~TIOCSER_TEMT
;
955 return put_user(result
, value
);
958 static int uart_tiocmget(struct tty_struct
*tty
)
960 struct uart_state
*state
= tty
->driver_data
;
961 struct tty_port
*port
= &state
->port
;
962 struct uart_port
*uport
= state
->uart_port
;
965 mutex_lock(&port
->mutex
);
966 if (!(tty
->flags
& (1 << TTY_IO_ERROR
))) {
967 result
= uport
->mctrl
;
968 spin_lock_irq(&uport
->lock
);
969 result
|= uport
->ops
->get_mctrl(uport
);
970 spin_unlock_irq(&uport
->lock
);
972 mutex_unlock(&port
->mutex
);
978 uart_tiocmset(struct tty_struct
*tty
, unsigned int set
, unsigned int clear
)
980 struct uart_state
*state
= tty
->driver_data
;
981 struct uart_port
*uport
= state
->uart_port
;
982 struct tty_port
*port
= &state
->port
;
985 mutex_lock(&port
->mutex
);
986 if (!(tty
->flags
& (1 << TTY_IO_ERROR
))) {
987 uart_update_mctrl(uport
, set
, clear
);
990 mutex_unlock(&port
->mutex
);
994 static int uart_break_ctl(struct tty_struct
*tty
, int break_state
)
996 struct uart_state
*state
= tty
->driver_data
;
997 struct tty_port
*port
= &state
->port
;
998 struct uart_port
*uport
= state
->uart_port
;
1000 mutex_lock(&port
->mutex
);
1002 if (uport
->type
!= PORT_UNKNOWN
)
1003 uport
->ops
->break_ctl(uport
, break_state
);
1005 mutex_unlock(&port
->mutex
);
1009 static int uart_do_autoconfig(struct tty_struct
*tty
,struct uart_state
*state
)
1011 struct uart_port
*uport
= state
->uart_port
;
1012 struct tty_port
*port
= &state
->port
;
1015 if (!capable(CAP_SYS_ADMIN
))
1019 * Take the per-port semaphore. This prevents count from
1020 * changing, and hence any extra opens of the port while
1021 * we're auto-configuring.
1023 if (mutex_lock_interruptible(&port
->mutex
))
1024 return -ERESTARTSYS
;
1027 if (tty_port_users(port
) == 1) {
1028 uart_shutdown(tty
, state
);
1031 * If we already have a port type configured,
1032 * we must release its resources.
1034 if (uport
->type
!= PORT_UNKNOWN
)
1035 uport
->ops
->release_port(uport
);
1037 flags
= UART_CONFIG_TYPE
;
1038 if (uport
->flags
& UPF_AUTO_IRQ
)
1039 flags
|= UART_CONFIG_IRQ
;
1042 * This will claim the ports resources if
1045 uport
->ops
->config_port(uport
, flags
);
1047 ret
= uart_startup(tty
, state
, 1);
1049 mutex_unlock(&port
->mutex
);
1054 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1055 * - mask passed in arg for lines of interest
1056 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1057 * Caller should use TIOCGICOUNT to see which one it was
1059 * FIXME: This wants extracting into a common all driver implementation
1060 * of TIOCMWAIT using tty_port.
1063 uart_wait_modem_status(struct uart_state
*state
, unsigned long arg
)
1065 struct uart_port
*uport
= state
->uart_port
;
1066 struct tty_port
*port
= &state
->port
;
1067 DECLARE_WAITQUEUE(wait
, current
);
1068 struct uart_icount cprev
, cnow
;
1072 * note the counters on entry
1074 spin_lock_irq(&uport
->lock
);
1075 memcpy(&cprev
, &uport
->icount
, sizeof(struct uart_icount
));
1078 * Force modem status interrupts on
1080 uport
->ops
->enable_ms(uport
);
1081 spin_unlock_irq(&uport
->lock
);
1083 add_wait_queue(&port
->delta_msr_wait
, &wait
);
1085 spin_lock_irq(&uport
->lock
);
1086 memcpy(&cnow
, &uport
->icount
, sizeof(struct uart_icount
));
1087 spin_unlock_irq(&uport
->lock
);
1089 set_current_state(TASK_INTERRUPTIBLE
);
1091 if (((arg
& TIOCM_RNG
) && (cnow
.rng
!= cprev
.rng
)) ||
1092 ((arg
& TIOCM_DSR
) && (cnow
.dsr
!= cprev
.dsr
)) ||
1093 ((arg
& TIOCM_CD
) && (cnow
.dcd
!= cprev
.dcd
)) ||
1094 ((arg
& TIOCM_CTS
) && (cnow
.cts
!= cprev
.cts
))) {
1101 /* see if a signal did it */
1102 if (signal_pending(current
)) {
1110 current
->state
= TASK_RUNNING
;
1111 remove_wait_queue(&port
->delta_msr_wait
, &wait
);
1117 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1118 * Return: write counters to the user passed counter struct
1119 * NB: both 1->0 and 0->1 transitions are counted except for
1120 * RI where only 0->1 is counted.
1122 static int uart_get_icount(struct tty_struct
*tty
,
1123 struct serial_icounter_struct
*icount
)
1125 struct uart_state
*state
= tty
->driver_data
;
1126 struct uart_icount cnow
;
1127 struct uart_port
*uport
= state
->uart_port
;
1129 spin_lock_irq(&uport
->lock
);
1130 memcpy(&cnow
, &uport
->icount
, sizeof(struct uart_icount
));
1131 spin_unlock_irq(&uport
->lock
);
1133 icount
->cts
= cnow
.cts
;
1134 icount
->dsr
= cnow
.dsr
;
1135 icount
->rng
= cnow
.rng
;
1136 icount
->dcd
= cnow
.dcd
;
1137 icount
->rx
= cnow
.rx
;
1138 icount
->tx
= cnow
.tx
;
1139 icount
->frame
= cnow
.frame
;
1140 icount
->overrun
= cnow
.overrun
;
1141 icount
->parity
= cnow
.parity
;
1142 icount
->brk
= cnow
.brk
;
1143 icount
->buf_overrun
= cnow
.buf_overrun
;
1149 * Called via sys_ioctl. We can use spin_lock_irq() here.
1152 uart_ioctl(struct tty_struct
*tty
, unsigned int cmd
,
1155 struct uart_state
*state
= tty
->driver_data
;
1156 struct tty_port
*port
= &state
->port
;
1157 void __user
*uarg
= (void __user
*)arg
;
1158 int ret
= -ENOIOCTLCMD
;
1162 * These ioctls don't rely on the hardware to be present.
1166 ret
= uart_get_info_user(port
, uarg
);
1170 ret
= uart_set_info_user(tty
, state
, uarg
);
1174 ret
= uart_do_autoconfig(tty
, state
);
1177 case TIOCSERGWILD
: /* obsolete */
1178 case TIOCSERSWILD
: /* obsolete */
1183 if (ret
!= -ENOIOCTLCMD
)
1186 if (tty
->flags
& (1 << TTY_IO_ERROR
)) {
1192 * The following should only be used when hardware is present.
1196 ret
= uart_wait_modem_status(state
, arg
);
1200 if (ret
!= -ENOIOCTLCMD
)
1203 mutex_lock(&port
->mutex
);
1205 if (tty
->flags
& (1 << TTY_IO_ERROR
)) {
1211 * All these rely on hardware being present and need to be
1212 * protected against the tty being hung up.
1215 case TIOCSERGETLSR
: /* Get line status register */
1216 ret
= uart_get_lsr_info(tty
, state
, uarg
);
1220 struct uart_port
*uport
= state
->uart_port
;
1221 if (uport
->ops
->ioctl
)
1222 ret
= uport
->ops
->ioctl(uport
, cmd
, arg
);
1227 mutex_unlock(&port
->mutex
);
1232 static void uart_set_ldisc(struct tty_struct
*tty
)
1234 struct uart_state
*state
= tty
->driver_data
;
1235 struct uart_port
*uport
= state
->uart_port
;
1237 if (uport
->ops
->set_ldisc
)
1238 uport
->ops
->set_ldisc(uport
, tty
->termios
.c_line
);
1241 static void uart_set_termios(struct tty_struct
*tty
,
1242 struct ktermios
*old_termios
)
1244 struct uart_state
*state
= tty
->driver_data
;
1245 struct uart_port
*uport
= state
->uart_port
;
1246 unsigned long flags
;
1247 unsigned int cflag
= tty
->termios
.c_cflag
;
1248 unsigned int iflag_mask
= IGNBRK
|BRKINT
|IGNPAR
|PARMRK
|INPCK
;
1249 bool sw_changed
= false;
1252 * Drivers doing software flow control also need to know
1253 * about changes to these input settings.
1255 if (uport
->flags
& UPF_SOFT_FLOW
) {
1256 iflag_mask
|= IXANY
|IXON
|IXOFF
;
1258 tty
->termios
.c_cc
[VSTART
] != old_termios
->c_cc
[VSTART
] ||
1259 tty
->termios
.c_cc
[VSTOP
] != old_termios
->c_cc
[VSTOP
];
1263 * These are the bits that are used to setup various
1264 * flags in the low level driver. We can ignore the Bfoo
1265 * bits in c_cflag; c_[io]speed will always be set
1266 * appropriately by set_termios() in tty_ioctl.c
1268 if ((cflag
^ old_termios
->c_cflag
) == 0 &&
1269 tty
->termios
.c_ospeed
== old_termios
->c_ospeed
&&
1270 tty
->termios
.c_ispeed
== old_termios
->c_ispeed
&&
1271 ((tty
->termios
.c_iflag
^ old_termios
->c_iflag
) & iflag_mask
) == 0 &&
1276 uart_change_speed(tty
, state
, old_termios
);
1278 /* Handle transition to B0 status */
1279 if ((old_termios
->c_cflag
& CBAUD
) && !(cflag
& CBAUD
))
1280 uart_clear_mctrl(uport
, TIOCM_RTS
| TIOCM_DTR
);
1281 /* Handle transition away from B0 status */
1282 else if (!(old_termios
->c_cflag
& CBAUD
) && (cflag
& CBAUD
)) {
1283 unsigned int mask
= TIOCM_DTR
;
1284 if (!(cflag
& CRTSCTS
) ||
1285 !test_bit(TTY_THROTTLED
, &tty
->flags
))
1287 uart_set_mctrl(uport
, mask
);
1291 * If the port is doing h/w assisted flow control, do nothing.
1292 * We assume that tty->hw_stopped has never been set.
1294 if (uport
->flags
& UPF_HARD_FLOW
)
1297 /* Handle turning off CRTSCTS */
1298 if ((old_termios
->c_cflag
& CRTSCTS
) && !(cflag
& CRTSCTS
)) {
1299 spin_lock_irqsave(&uport
->lock
, flags
);
1300 tty
->hw_stopped
= 0;
1302 spin_unlock_irqrestore(&uport
->lock
, flags
);
1304 /* Handle turning on CRTSCTS */
1305 else if (!(old_termios
->c_cflag
& CRTSCTS
) && (cflag
& CRTSCTS
)) {
1306 spin_lock_irqsave(&uport
->lock
, flags
);
1307 if (!(uport
->ops
->get_mctrl(uport
) & TIOCM_CTS
)) {
1308 tty
->hw_stopped
= 1;
1309 uport
->ops
->stop_tx(uport
);
1311 spin_unlock_irqrestore(&uport
->lock
, flags
);
1316 * Calls to uart_close() are serialised via the tty_lock in
1317 * drivers/tty/tty_io.c:tty_release()
1318 * drivers/tty/tty_io.c:do_tty_hangup()
1319 * This runs from a workqueue and can sleep for a _short_ time only.
1321 static void uart_close(struct tty_struct
*tty
, struct file
*filp
)
1323 struct uart_state
*state
= tty
->driver_data
;
1324 struct tty_port
*port
;
1325 struct uart_port
*uport
;
1326 unsigned long flags
;
1331 uport
= state
->uart_port
;
1332 port
= &state
->port
;
1334 pr_debug("uart_close(%d) called\n", uport
? uport
->line
: -1);
1336 if (!port
->count
|| tty_port_close_start(port
, tty
, filp
) == 0)
1340 * At this point, we stop accepting input. To do this, we
1341 * disable the receive line status interrupts.
1343 if (port
->flags
& ASYNC_INITIALIZED
) {
1344 unsigned long flags
;
1345 spin_lock_irqsave(&uport
->lock
, flags
);
1346 uport
->ops
->stop_rx(uport
);
1347 spin_unlock_irqrestore(&uport
->lock
, flags
);
1349 * Before we drop DTR, make sure the UART transmitter
1350 * has completely drained; this is especially
1351 * important if there is a transmit FIFO!
1353 uart_wait_until_sent(tty
, uport
->timeout
);
1356 mutex_lock(&port
->mutex
);
1357 uart_shutdown(tty
, state
);
1358 uart_flush_buffer(tty
);
1360 tty_ldisc_flush(tty
);
1362 tty_port_tty_set(port
, NULL
);
1363 spin_lock_irqsave(&port
->lock
, flags
);
1366 if (port
->blocked_open
) {
1367 spin_unlock_irqrestore(&port
->lock
, flags
);
1368 if (port
->close_delay
)
1369 msleep_interruptible(
1370 jiffies_to_msecs(port
->close_delay
));
1371 spin_lock_irqsave(&port
->lock
, flags
);
1372 } else if (!uart_console(uport
)) {
1373 spin_unlock_irqrestore(&port
->lock
, flags
);
1374 uart_change_pm(state
, UART_PM_STATE_OFF
);
1375 spin_lock_irqsave(&port
->lock
, flags
);
1379 * Wake up anyone trying to open this port.
1381 clear_bit(ASYNCB_NORMAL_ACTIVE
, &port
->flags
);
1382 clear_bit(ASYNCB_CLOSING
, &port
->flags
);
1383 spin_unlock_irqrestore(&port
->lock
, flags
);
1384 wake_up_interruptible(&port
->open_wait
);
1385 wake_up_interruptible(&port
->close_wait
);
1387 mutex_unlock(&port
->mutex
);
1390 static void uart_wait_until_sent(struct tty_struct
*tty
, int timeout
)
1392 struct uart_state
*state
= tty
->driver_data
;
1393 struct uart_port
*port
= state
->uart_port
;
1394 unsigned long char_time
, expire
;
1396 if (port
->type
== PORT_UNKNOWN
|| port
->fifosize
== 0)
1400 * Set the check interval to be 1/5 of the estimated time to
1401 * send a single character, and make it at least 1. The check
1402 * interval should also be less than the timeout.
1404 * Note: we have to use pretty tight timings here to satisfy
1407 char_time
= (port
->timeout
- HZ
/50) / port
->fifosize
;
1408 char_time
= char_time
/ 5;
1411 if (timeout
&& timeout
< char_time
)
1412 char_time
= timeout
;
1415 * If the transmitter hasn't cleared in twice the approximate
1416 * amount of time to send the entire FIFO, it probably won't
1417 * ever clear. This assumes the UART isn't doing flow
1418 * control, which is currently the case. Hence, if it ever
1419 * takes longer than port->timeout, this is probably due to a
1420 * UART bug of some kind. So, we clamp the timeout parameter at
1423 if (timeout
== 0 || timeout
> 2 * port
->timeout
)
1424 timeout
= 2 * port
->timeout
;
1426 expire
= jiffies
+ timeout
;
1428 pr_debug("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n",
1429 port
->line
, jiffies
, expire
);
1432 * Check whether the transmitter is empty every 'char_time'.
1433 * 'timeout' / 'expire' give us the maximum amount of time
1436 while (!port
->ops
->tx_empty(port
)) {
1437 msleep_interruptible(jiffies_to_msecs(char_time
));
1438 if (signal_pending(current
))
1440 if (time_after(jiffies
, expire
))
1446 * Calls to uart_hangup() are serialised by the tty_lock in
1447 * drivers/tty/tty_io.c:do_tty_hangup()
1448 * This runs from a workqueue and can sleep for a _short_ time only.
1450 static void uart_hangup(struct tty_struct
*tty
)
1452 struct uart_state
*state
= tty
->driver_data
;
1453 struct tty_port
*port
= &state
->port
;
1454 unsigned long flags
;
1456 pr_debug("uart_hangup(%d)\n", state
->uart_port
->line
);
1458 mutex_lock(&port
->mutex
);
1459 if (port
->flags
& ASYNC_NORMAL_ACTIVE
) {
1460 uart_flush_buffer(tty
);
1461 uart_shutdown(tty
, state
);
1462 spin_lock_irqsave(&port
->lock
, flags
);
1464 clear_bit(ASYNCB_NORMAL_ACTIVE
, &port
->flags
);
1465 spin_unlock_irqrestore(&port
->lock
, flags
);
1466 tty_port_tty_set(port
, NULL
);
1467 if (!uart_console(state
->uart_port
))
1468 uart_change_pm(state
, UART_PM_STATE_OFF
);
1469 wake_up_interruptible(&port
->open_wait
);
1470 wake_up_interruptible(&port
->delta_msr_wait
);
1472 mutex_unlock(&port
->mutex
);
1475 static int uart_port_activate(struct tty_port
*port
, struct tty_struct
*tty
)
1480 static void uart_port_shutdown(struct tty_port
*port
)
1482 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1483 struct uart_port
*uport
= state
->uart_port
;
1486 * clear delta_msr_wait queue to avoid mem leaks: we may free
1487 * the irq here so the queue might never be woken up. Note
1488 * that we won't end up waiting on delta_msr_wait again since
1489 * any outstanding file descriptors should be pointing at
1490 * hung_up_tty_fops now.
1492 wake_up_interruptible(&port
->delta_msr_wait
);
1495 * Free the IRQ and disable the port.
1497 uport
->ops
->shutdown(uport
);
1500 * Ensure that the IRQ handler isn't running on another CPU.
1502 synchronize_irq(uport
->irq
);
1505 static int uart_carrier_raised(struct tty_port
*port
)
1507 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1508 struct uart_port
*uport
= state
->uart_port
;
1510 spin_lock_irq(&uport
->lock
);
1511 uport
->ops
->enable_ms(uport
);
1512 mctrl
= uport
->ops
->get_mctrl(uport
);
1513 spin_unlock_irq(&uport
->lock
);
1514 if (mctrl
& TIOCM_CAR
)
1519 static void uart_dtr_rts(struct tty_port
*port
, int onoff
)
1521 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1522 struct uart_port
*uport
= state
->uart_port
;
1525 uart_set_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
1527 uart_clear_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
1531 * Calls to uart_open are serialised by the tty_lock in
1532 * drivers/tty/tty_io.c:tty_open()
1533 * Note that if this fails, then uart_close() _will_ be called.
1535 * In time, we want to scrap the "opening nonpresent ports"
1536 * behaviour and implement an alternative way for setserial
1537 * to set base addresses/ports/types. This will allow us to
1538 * get rid of a certain amount of extra tests.
1540 static int uart_open(struct tty_struct
*tty
, struct file
*filp
)
1542 struct uart_driver
*drv
= (struct uart_driver
*)tty
->driver
->driver_state
;
1543 int retval
, line
= tty
->index
;
1544 struct uart_state
*state
= drv
->state
+ line
;
1545 struct tty_port
*port
= &state
->port
;
1547 pr_debug("uart_open(%d) called\n", line
);
1550 * We take the semaphore here to guarantee that we won't be re-entered
1551 * while allocating the state structure, or while we request any IRQs
1552 * that the driver may need. This also has the nice side-effect that
1553 * it delays the action of uart_hangup, so we can guarantee that
1554 * state->port.tty will always contain something reasonable.
1556 if (mutex_lock_interruptible(&port
->mutex
)) {
1557 retval
= -ERESTARTSYS
;
1562 if (!state
->uart_port
|| state
->uart_port
->flags
& UPF_DEAD
) {
1568 * Once we set tty->driver_data here, we are guaranteed that
1569 * uart_close() will decrement the driver module use count.
1570 * Any failures from here onwards should not touch the count.
1572 tty
->driver_data
= state
;
1573 state
->uart_port
->state
= state
;
1574 state
->port
.low_latency
=
1575 (state
->uart_port
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
1576 tty_port_tty_set(port
, tty
);
1579 * If the port is in the middle of closing, bail out now.
1581 if (tty_hung_up_p(filp
)) {
1587 * Start up the serial port.
1589 retval
= uart_startup(tty
, state
, 0);
1592 * If we succeeded, wait until the port is ready.
1594 mutex_unlock(&port
->mutex
);
1596 retval
= tty_port_block_til_ready(port
, tty
, filp
);
1602 mutex_unlock(&port
->mutex
);
1606 static const char *uart_type(struct uart_port
*port
)
1608 const char *str
= NULL
;
1610 if (port
->ops
->type
)
1611 str
= port
->ops
->type(port
);
1619 #ifdef CONFIG_PROC_FS
1621 static void uart_line_info(struct seq_file
*m
, struct uart_driver
*drv
, int i
)
1623 struct uart_state
*state
= drv
->state
+ i
;
1624 struct tty_port
*port
= &state
->port
;
1625 enum uart_pm_state pm_state
;
1626 struct uart_port
*uport
= state
->uart_port
;
1628 unsigned int status
;
1634 mmio
= uport
->iotype
>= UPIO_MEM
;
1635 seq_printf(m
, "%d: uart:%s %s%08llX irq:%d",
1636 uport
->line
, uart_type(uport
),
1637 mmio
? "mmio:0x" : "port:",
1638 mmio
? (unsigned long long)uport
->mapbase
1639 : (unsigned long long)uport
->iobase
,
1642 if (uport
->type
== PORT_UNKNOWN
) {
1647 if (capable(CAP_SYS_ADMIN
)) {
1648 mutex_lock(&port
->mutex
);
1649 pm_state
= state
->pm_state
;
1650 if (pm_state
!= UART_PM_STATE_ON
)
1651 uart_change_pm(state
, UART_PM_STATE_ON
);
1652 spin_lock_irq(&uport
->lock
);
1653 status
= uport
->ops
->get_mctrl(uport
);
1654 spin_unlock_irq(&uport
->lock
);
1655 if (pm_state
!= UART_PM_STATE_ON
)
1656 uart_change_pm(state
, pm_state
);
1657 mutex_unlock(&port
->mutex
);
1659 seq_printf(m
, " tx:%d rx:%d",
1660 uport
->icount
.tx
, uport
->icount
.rx
);
1661 if (uport
->icount
.frame
)
1662 seq_printf(m
, " fe:%d",
1663 uport
->icount
.frame
);
1664 if (uport
->icount
.parity
)
1665 seq_printf(m
, " pe:%d",
1666 uport
->icount
.parity
);
1667 if (uport
->icount
.brk
)
1668 seq_printf(m
, " brk:%d",
1670 if (uport
->icount
.overrun
)
1671 seq_printf(m
, " oe:%d",
1672 uport
->icount
.overrun
);
1674 #define INFOBIT(bit, str) \
1675 if (uport->mctrl & (bit)) \
1676 strncat(stat_buf, (str), sizeof(stat_buf) - \
1677 strlen(stat_buf) - 2)
1678 #define STATBIT(bit, str) \
1679 if (status & (bit)) \
1680 strncat(stat_buf, (str), sizeof(stat_buf) - \
1681 strlen(stat_buf) - 2)
1685 INFOBIT(TIOCM_RTS
, "|RTS");
1686 STATBIT(TIOCM_CTS
, "|CTS");
1687 INFOBIT(TIOCM_DTR
, "|DTR");
1688 STATBIT(TIOCM_DSR
, "|DSR");
1689 STATBIT(TIOCM_CAR
, "|CD");
1690 STATBIT(TIOCM_RNG
, "|RI");
1694 seq_puts(m
, stat_buf
);
1701 static int uart_proc_show(struct seq_file
*m
, void *v
)
1703 struct tty_driver
*ttydrv
= m
->private;
1704 struct uart_driver
*drv
= ttydrv
->driver_state
;
1707 seq_printf(m
, "serinfo:1.0 driver%s%s revision:%s\n",
1709 for (i
= 0; i
< drv
->nr
; i
++)
1710 uart_line_info(m
, drv
, i
);
1714 static int uart_proc_open(struct inode
*inode
, struct file
*file
)
1716 return single_open(file
, uart_proc_show
, PDE_DATA(inode
));
1719 static const struct file_operations uart_proc_fops
= {
1720 .owner
= THIS_MODULE
,
1721 .open
= uart_proc_open
,
1723 .llseek
= seq_lseek
,
1724 .release
= single_release
,
1728 #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(CONFIG_CONSOLE_POLL)
1730 * uart_console_write - write a console message to a serial port
1731 * @port: the port to write the message
1732 * @s: array of characters
1733 * @count: number of characters in string to write
1734 * @write: function to write character to port
1736 void uart_console_write(struct uart_port
*port
, const char *s
,
1738 void (*putchar
)(struct uart_port
*, int))
1742 for (i
= 0; i
< count
; i
++, s
++) {
1744 putchar(port
, '\r');
1748 EXPORT_SYMBOL_GPL(uart_console_write
);
1751 * Check whether an invalid uart number has been specified, and
1752 * if so, search for the first available port that does have
1755 struct uart_port
* __init
1756 uart_get_console(struct uart_port
*ports
, int nr
, struct console
*co
)
1758 int idx
= co
->index
;
1760 if (idx
< 0 || idx
>= nr
|| (ports
[idx
].iobase
== 0 &&
1761 ports
[idx
].membase
== NULL
))
1762 for (idx
= 0; idx
< nr
; idx
++)
1763 if (ports
[idx
].iobase
!= 0 ||
1764 ports
[idx
].membase
!= NULL
)
1773 * uart_parse_options - Parse serial port baud/parity/bits/flow control.
1774 * @options: pointer to option string
1775 * @baud: pointer to an 'int' variable for the baud rate.
1776 * @parity: pointer to an 'int' variable for the parity.
1777 * @bits: pointer to an 'int' variable for the number of data bits.
1778 * @flow: pointer to an 'int' variable for the flow control character.
1780 * uart_parse_options decodes a string containing the serial console
1781 * options. The format of the string is <baud><parity><bits><flow>,
1785 uart_parse_options(char *options
, int *baud
, int *parity
, int *bits
, int *flow
)
1789 *baud
= simple_strtoul(s
, NULL
, 10);
1790 while (*s
>= '0' && *s
<= '9')
1799 EXPORT_SYMBOL_GPL(uart_parse_options
);
1806 static const struct baud_rates baud_rates
[] = {
1807 { 921600, B921600
},
1808 { 460800, B460800
},
1809 { 230400, B230400
},
1810 { 115200, B115200
},
1822 * uart_set_options - setup the serial console parameters
1823 * @port: pointer to the serial ports uart_port structure
1824 * @co: console pointer
1826 * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even)
1827 * @bits: number of data bits
1828 * @flow: flow control character - 'r' (rts)
1831 uart_set_options(struct uart_port
*port
, struct console
*co
,
1832 int baud
, int parity
, int bits
, int flow
)
1834 struct ktermios termios
;
1835 static struct ktermios dummy
;
1839 * Ensure that the serial console lock is initialised
1841 * If this port is a console, then the spinlock is already
1844 if (!(uart_console(port
) && (port
->cons
->flags
& CON_ENABLED
))) {
1845 spin_lock_init(&port
->lock
);
1846 lockdep_set_class(&port
->lock
, &port_lock_key
);
1849 memset(&termios
, 0, sizeof(struct ktermios
));
1851 termios
.c_cflag
= CREAD
| HUPCL
| CLOCAL
;
1854 * Construct a cflag setting.
1856 for (i
= 0; baud_rates
[i
].rate
; i
++)
1857 if (baud_rates
[i
].rate
<= baud
)
1860 termios
.c_cflag
|= baud_rates
[i
].cflag
;
1863 termios
.c_cflag
|= CS7
;
1865 termios
.c_cflag
|= CS8
;
1869 termios
.c_cflag
|= PARODD
;
1872 termios
.c_cflag
|= PARENB
;
1877 termios
.c_cflag
|= CRTSCTS
;
1880 * some uarts on other side don't support no flow control.
1881 * So we set * DTR in host uart to make them happy
1883 port
->mctrl
|= TIOCM_DTR
;
1885 port
->ops
->set_termios(port
, &termios
, &dummy
);
1887 * Allow the setting of the UART parameters with a NULL console
1891 co
->cflag
= termios
.c_cflag
;
1895 EXPORT_SYMBOL_GPL(uart_set_options
);
1896 #endif /* CONFIG_SERIAL_CORE_CONSOLE */
1899 * uart_change_pm - set power state of the port
1901 * @state: port descriptor
1902 * @pm_state: new state
1904 * Locking: port->mutex has to be held
1906 static void uart_change_pm(struct uart_state
*state
,
1907 enum uart_pm_state pm_state
)
1909 struct uart_port
*port
= state
->uart_port
;
1911 if (state
->pm_state
!= pm_state
) {
1913 port
->ops
->pm(port
, pm_state
, state
->pm_state
);
1914 state
->pm_state
= pm_state
;
1919 struct uart_port
*port
;
1920 struct uart_driver
*driver
;
1923 static int serial_match_port(struct device
*dev
, void *data
)
1925 struct uart_match
*match
= data
;
1926 struct tty_driver
*tty_drv
= match
->driver
->tty_driver
;
1927 dev_t devt
= MKDEV(tty_drv
->major
, tty_drv
->minor_start
) +
1930 return dev
->devt
== devt
; /* Actually, only one tty per port */
1933 int uart_suspend_port(struct uart_driver
*drv
, struct uart_port
*uport
)
1935 struct uart_state
*state
= drv
->state
+ uport
->line
;
1936 struct tty_port
*port
= &state
->port
;
1937 struct device
*tty_dev
;
1938 struct uart_match match
= {uport
, drv
};
1940 mutex_lock(&port
->mutex
);
1942 tty_dev
= device_find_child(uport
->dev
, &match
, serial_match_port
);
1943 if (device_may_wakeup(tty_dev
)) {
1944 if (!enable_irq_wake(uport
->irq
))
1945 uport
->irq_wake
= 1;
1946 put_device(tty_dev
);
1947 mutex_unlock(&port
->mutex
);
1950 put_device(tty_dev
);
1952 if (console_suspend_enabled
|| !uart_console(uport
))
1953 uport
->suspended
= 1;
1955 if (port
->flags
& ASYNC_INITIALIZED
) {
1956 const struct uart_ops
*ops
= uport
->ops
;
1959 if (console_suspend_enabled
|| !uart_console(uport
)) {
1960 set_bit(ASYNCB_SUSPENDED
, &port
->flags
);
1961 clear_bit(ASYNCB_INITIALIZED
, &port
->flags
);
1963 spin_lock_irq(&uport
->lock
);
1964 ops
->stop_tx(uport
);
1965 ops
->set_mctrl(uport
, 0);
1966 ops
->stop_rx(uport
);
1967 spin_unlock_irq(&uport
->lock
);
1971 * Wait for the transmitter to empty.
1973 for (tries
= 3; !ops
->tx_empty(uport
) && tries
; tries
--)
1976 printk(KERN_ERR
"%s%s%s%d: Unable to drain "
1978 uport
->dev
? dev_name(uport
->dev
) : "",
1979 uport
->dev
? ": " : "",
1981 drv
->tty_driver
->name_base
+ uport
->line
);
1983 if (console_suspend_enabled
|| !uart_console(uport
))
1984 ops
->shutdown(uport
);
1988 * Disable the console device before suspending.
1990 if (console_suspend_enabled
&& uart_console(uport
))
1991 console_stop(uport
->cons
);
1993 if (console_suspend_enabled
|| !uart_console(uport
))
1994 uart_change_pm(state
, UART_PM_STATE_OFF
);
1996 mutex_unlock(&port
->mutex
);
2001 int uart_resume_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2003 struct uart_state
*state
= drv
->state
+ uport
->line
;
2004 struct tty_port
*port
= &state
->port
;
2005 struct device
*tty_dev
;
2006 struct uart_match match
= {uport
, drv
};
2007 struct ktermios termios
;
2009 mutex_lock(&port
->mutex
);
2011 tty_dev
= device_find_child(uport
->dev
, &match
, serial_match_port
);
2012 if (!uport
->suspended
&& device_may_wakeup(tty_dev
)) {
2013 if (uport
->irq_wake
) {
2014 disable_irq_wake(uport
->irq
);
2015 uport
->irq_wake
= 0;
2017 put_device(tty_dev
);
2018 mutex_unlock(&port
->mutex
);
2021 put_device(tty_dev
);
2022 uport
->suspended
= 0;
2025 * Re-enable the console device after suspending.
2027 if (uart_console(uport
)) {
2029 * First try to use the console cflag setting.
2031 memset(&termios
, 0, sizeof(struct ktermios
));
2032 termios
.c_cflag
= uport
->cons
->cflag
;
2035 * If that's unset, use the tty termios setting.
2037 if (port
->tty
&& termios
.c_cflag
== 0)
2038 termios
= port
->tty
->termios
;
2040 if (console_suspend_enabled
)
2041 uart_change_pm(state
, UART_PM_STATE_ON
);
2042 uport
->ops
->set_termios(uport
, &termios
, NULL
);
2043 if (console_suspend_enabled
)
2044 console_start(uport
->cons
);
2047 if (port
->flags
& ASYNC_SUSPENDED
) {
2048 const struct uart_ops
*ops
= uport
->ops
;
2051 uart_change_pm(state
, UART_PM_STATE_ON
);
2052 spin_lock_irq(&uport
->lock
);
2053 ops
->set_mctrl(uport
, 0);
2054 spin_unlock_irq(&uport
->lock
);
2055 if (console_suspend_enabled
|| !uart_console(uport
)) {
2056 /* Protected by port mutex for now */
2057 struct tty_struct
*tty
= port
->tty
;
2058 ret
= ops
->startup(uport
);
2061 uart_change_speed(tty
, state
, NULL
);
2062 spin_lock_irq(&uport
->lock
);
2063 ops
->set_mctrl(uport
, uport
->mctrl
);
2064 ops
->start_tx(uport
);
2065 spin_unlock_irq(&uport
->lock
);
2066 set_bit(ASYNCB_INITIALIZED
, &port
->flags
);
2069 * Failed to resume - maybe hardware went away?
2070 * Clear the "initialized" flag so we won't try
2071 * to call the low level drivers shutdown method.
2073 uart_shutdown(tty
, state
);
2077 clear_bit(ASYNCB_SUSPENDED
, &port
->flags
);
2080 mutex_unlock(&port
->mutex
);
2086 uart_report_port(struct uart_driver
*drv
, struct uart_port
*port
)
2090 switch (port
->iotype
) {
2092 snprintf(address
, sizeof(address
), "I/O 0x%lx", port
->iobase
);
2095 snprintf(address
, sizeof(address
),
2096 "I/O 0x%lx offset 0x%x", port
->iobase
, port
->hub6
);
2102 snprintf(address
, sizeof(address
),
2103 "MMIO 0x%llx", (unsigned long long)port
->mapbase
);
2106 strlcpy(address
, "*unknown*", sizeof(address
));
2110 printk(KERN_INFO
"%s%s%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
2111 port
->dev
? dev_name(port
->dev
) : "",
2112 port
->dev
? ": " : "",
2114 drv
->tty_driver
->name_base
+ port
->line
,
2115 address
, port
->irq
, port
->uartclk
/ 16, uart_type(port
));
2119 uart_configure_port(struct uart_driver
*drv
, struct uart_state
*state
,
2120 struct uart_port
*port
)
2125 * If there isn't a port here, don't do anything further.
2127 if (!port
->iobase
&& !port
->mapbase
&& !port
->membase
)
2131 * Now do the auto configuration stuff. Note that config_port
2132 * is expected to claim the resources and map the port for us.
2135 if (port
->flags
& UPF_AUTO_IRQ
)
2136 flags
|= UART_CONFIG_IRQ
;
2137 if (port
->flags
& UPF_BOOT_AUTOCONF
) {
2138 if (!(port
->flags
& UPF_FIXED_TYPE
)) {
2139 port
->type
= PORT_UNKNOWN
;
2140 flags
|= UART_CONFIG_TYPE
;
2142 port
->ops
->config_port(port
, flags
);
2145 if (port
->type
!= PORT_UNKNOWN
) {
2146 unsigned long flags
;
2148 uart_report_port(drv
, port
);
2150 /* Power up port for set_mctrl() */
2151 uart_change_pm(state
, UART_PM_STATE_ON
);
2154 * Ensure that the modem control lines are de-activated.
2155 * keep the DTR setting that is set in uart_set_options()
2156 * We probably don't need a spinlock around this, but
2158 spin_lock_irqsave(&port
->lock
, flags
);
2159 port
->ops
->set_mctrl(port
, port
->mctrl
& TIOCM_DTR
);
2160 spin_unlock_irqrestore(&port
->lock
, flags
);
2163 * If this driver supports console, and it hasn't been
2164 * successfully registered yet, try to re-register it.
2165 * It may be that the port was not available.
2167 if (port
->cons
&& !(port
->cons
->flags
& CON_ENABLED
))
2168 register_console(port
->cons
);
2171 * Power down all ports by default, except the
2172 * console if we have one.
2174 if (!uart_console(port
))
2175 uart_change_pm(state
, UART_PM_STATE_OFF
);
2179 #ifdef CONFIG_CONSOLE_POLL
2181 static int uart_poll_init(struct tty_driver
*driver
, int line
, char *options
)
2183 struct uart_driver
*drv
= driver
->driver_state
;
2184 struct uart_state
*state
= drv
->state
+ line
;
2185 struct uart_port
*port
;
2192 if (!state
|| !state
->uart_port
)
2195 port
= state
->uart_port
;
2196 if (!(port
->ops
->poll_get_char
&& port
->ops
->poll_put_char
))
2199 if (port
->ops
->poll_init
) {
2200 struct tty_port
*tport
= &state
->port
;
2203 mutex_lock(&tport
->mutex
);
2205 * We don't set ASYNCB_INITIALIZED as we only initialized the
2206 * hw, e.g. state->xmit is still uninitialized.
2208 if (!test_bit(ASYNCB_INITIALIZED
, &tport
->flags
))
2209 ret
= port
->ops
->poll_init(port
);
2210 mutex_unlock(&tport
->mutex
);
2216 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
2217 return uart_set_options(port
, NULL
, baud
, parity
, bits
, flow
);
2223 static int uart_poll_get_char(struct tty_driver
*driver
, int line
)
2225 struct uart_driver
*drv
= driver
->driver_state
;
2226 struct uart_state
*state
= drv
->state
+ line
;
2227 struct uart_port
*port
;
2229 if (!state
|| !state
->uart_port
)
2232 port
= state
->uart_port
;
2233 return port
->ops
->poll_get_char(port
);
2236 static void uart_poll_put_char(struct tty_driver
*driver
, int line
, char ch
)
2238 struct uart_driver
*drv
= driver
->driver_state
;
2239 struct uart_state
*state
= drv
->state
+ line
;
2240 struct uart_port
*port
;
2242 if (!state
|| !state
->uart_port
)
2245 port
= state
->uart_port
;
2248 port
->ops
->poll_put_char(port
, '\r');
2249 port
->ops
->poll_put_char(port
, ch
);
2253 static const struct tty_operations uart_ops
= {
2255 .close
= uart_close
,
2256 .write
= uart_write
,
2257 .put_char
= uart_put_char
,
2258 .flush_chars
= uart_flush_chars
,
2259 .write_room
= uart_write_room
,
2260 .chars_in_buffer
= uart_chars_in_buffer
,
2261 .flush_buffer
= uart_flush_buffer
,
2262 .ioctl
= uart_ioctl
,
2263 .throttle
= uart_throttle
,
2264 .unthrottle
= uart_unthrottle
,
2265 .send_xchar
= uart_send_xchar
,
2266 .set_termios
= uart_set_termios
,
2267 .set_ldisc
= uart_set_ldisc
,
2269 .start
= uart_start
,
2270 .hangup
= uart_hangup
,
2271 .break_ctl
= uart_break_ctl
,
2272 .wait_until_sent
= uart_wait_until_sent
,
2273 #ifdef CONFIG_PROC_FS
2274 .proc_fops
= &uart_proc_fops
,
2276 .tiocmget
= uart_tiocmget
,
2277 .tiocmset
= uart_tiocmset
,
2278 .get_icount
= uart_get_icount
,
2279 #ifdef CONFIG_CONSOLE_POLL
2280 .poll_init
= uart_poll_init
,
2281 .poll_get_char
= uart_poll_get_char
,
2282 .poll_put_char
= uart_poll_put_char
,
2286 static const struct tty_port_operations uart_port_ops
= {
2287 .activate
= uart_port_activate
,
2288 .shutdown
= uart_port_shutdown
,
2289 .carrier_raised
= uart_carrier_raised
,
2290 .dtr_rts
= uart_dtr_rts
,
2294 * uart_register_driver - register a driver with the uart core layer
2295 * @drv: low level driver structure
2297 * Register a uart driver with the core driver. We in turn register
2298 * with the tty layer, and initialise the core driver per-port state.
2300 * We have a proc file in /proc/tty/driver which is named after the
2303 * drv->port should be NULL, and the per-port structures should be
2304 * registered using uart_add_one_port after this call has succeeded.
2306 int uart_register_driver(struct uart_driver
*drv
)
2308 struct tty_driver
*normal
;
2314 * Maybe we should be using a slab cache for this, especially if
2315 * we have a large number of ports to handle.
2317 drv
->state
= kzalloc(sizeof(struct uart_state
) * drv
->nr
, GFP_KERNEL
);
2321 normal
= alloc_tty_driver(drv
->nr
);
2325 drv
->tty_driver
= normal
;
2327 normal
->driver_name
= drv
->driver_name
;
2328 normal
->name
= drv
->dev_name
;
2329 normal
->major
= drv
->major
;
2330 normal
->minor_start
= drv
->minor
;
2331 normal
->type
= TTY_DRIVER_TYPE_SERIAL
;
2332 normal
->subtype
= SERIAL_TYPE_NORMAL
;
2333 normal
->init_termios
= tty_std_termios
;
2334 normal
->init_termios
.c_cflag
= B9600
| CS8
| CREAD
| HUPCL
| CLOCAL
;
2335 normal
->init_termios
.c_ispeed
= normal
->init_termios
.c_ospeed
= 9600;
2336 normal
->flags
= TTY_DRIVER_REAL_RAW
| TTY_DRIVER_DYNAMIC_DEV
;
2337 normal
->driver_state
= drv
;
2338 tty_set_operations(normal
, &uart_ops
);
2341 * Initialise the UART state(s).
2343 for (i
= 0; i
< drv
->nr
; i
++) {
2344 struct uart_state
*state
= drv
->state
+ i
;
2345 struct tty_port
*port
= &state
->port
;
2347 tty_port_init(port
);
2348 port
->ops
= &uart_port_ops
;
2349 port
->close_delay
= HZ
/ 2; /* .5 seconds */
2350 port
->closing_wait
= 30 * HZ
;/* 30 seconds */
2353 retval
= tty_register_driver(normal
);
2357 for (i
= 0; i
< drv
->nr
; i
++)
2358 tty_port_destroy(&drv
->state
[i
].port
);
2359 put_tty_driver(normal
);
2367 * uart_unregister_driver - remove a driver from the uart core layer
2368 * @drv: low level driver structure
2370 * Remove all references to a driver from the core driver. The low
2371 * level driver must have removed all its ports via the
2372 * uart_remove_one_port() if it registered them with uart_add_one_port().
2373 * (ie, drv->port == NULL)
2375 void uart_unregister_driver(struct uart_driver
*drv
)
2377 struct tty_driver
*p
= drv
->tty_driver
;
2380 tty_unregister_driver(p
);
2382 for (i
= 0; i
< drv
->nr
; i
++)
2383 tty_port_destroy(&drv
->state
[i
].port
);
2386 drv
->tty_driver
= NULL
;
2389 struct tty_driver
*uart_console_device(struct console
*co
, int *index
)
2391 struct uart_driver
*p
= co
->data
;
2393 return p
->tty_driver
;
2396 static ssize_t
uart_get_attr_uartclk(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
.baud_base
* 16);
2406 static ssize_t
uart_get_attr_type(struct device
*dev
,
2407 struct device_attribute
*attr
, char *buf
)
2409 struct serial_struct tmp
;
2410 struct tty_port
*port
= dev_get_drvdata(dev
);
2412 uart_get_info(port
, &tmp
);
2413 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.type
);
2415 static ssize_t
uart_get_attr_line(struct device
*dev
,
2416 struct device_attribute
*attr
, char *buf
)
2418 struct serial_struct tmp
;
2419 struct tty_port
*port
= dev_get_drvdata(dev
);
2421 uart_get_info(port
, &tmp
);
2422 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.line
);
2425 static ssize_t
uart_get_attr_port(struct device
*dev
,
2426 struct device_attribute
*attr
, char *buf
)
2428 struct serial_struct tmp
;
2429 struct tty_port
*port
= dev_get_drvdata(dev
);
2430 unsigned long ioaddr
;
2432 uart_get_info(port
, &tmp
);
2434 if (HIGH_BITS_OFFSET
)
2435 ioaddr
|= (unsigned long)tmp
.port_high
<< HIGH_BITS_OFFSET
;
2436 return snprintf(buf
, PAGE_SIZE
, "0x%lX\n", ioaddr
);
2439 static ssize_t
uart_get_attr_irq(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
, "%d\n", tmp
.irq
);
2449 static ssize_t
uart_get_attr_flags(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
, "0x%X\n", tmp
.flags
);
2459 static ssize_t
uart_get_attr_xmit_fifo_size(struct device
*dev
,
2460 struct device_attribute
*attr
, char *buf
)
2462 struct serial_struct tmp
;
2463 struct tty_port
*port
= dev_get_drvdata(dev
);
2465 uart_get_info(port
, &tmp
);
2466 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.xmit_fifo_size
);
2470 static ssize_t
uart_get_attr_close_delay(struct device
*dev
,
2471 struct device_attribute
*attr
, char *buf
)
2473 struct serial_struct tmp
;
2474 struct tty_port
*port
= dev_get_drvdata(dev
);
2476 uart_get_info(port
, &tmp
);
2477 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.close_delay
);
2481 static ssize_t
uart_get_attr_closing_wait(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
.closing_wait
);
2491 static ssize_t
uart_get_attr_custom_divisor(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
.custom_divisor
);
2501 static ssize_t
uart_get_attr_io_type(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
, "%d\n", tmp
.io_type
);
2511 static ssize_t
uart_get_attr_iomem_base(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
, "0x%lX\n", (unsigned long)tmp
.iomem_base
);
2521 static ssize_t
uart_get_attr_iomem_reg_shift(struct device
*dev
,
2522 struct device_attribute
*attr
, char *buf
)
2524 struct serial_struct tmp
;
2525 struct tty_port
*port
= dev_get_drvdata(dev
);
2527 uart_get_info(port
, &tmp
);
2528 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.iomem_reg_shift
);
2531 static DEVICE_ATTR(type
, S_IRUSR
| S_IRGRP
, uart_get_attr_type
, NULL
);
2532 static DEVICE_ATTR(line
, S_IRUSR
| S_IRGRP
, uart_get_attr_line
, NULL
);
2533 static DEVICE_ATTR(port
, S_IRUSR
| S_IRGRP
, uart_get_attr_port
, NULL
);
2534 static DEVICE_ATTR(irq
, S_IRUSR
| S_IRGRP
, uart_get_attr_irq
, NULL
);
2535 static DEVICE_ATTR(flags
, S_IRUSR
| S_IRGRP
, uart_get_attr_flags
, NULL
);
2536 static DEVICE_ATTR(xmit_fifo_size
, S_IRUSR
| S_IRGRP
, uart_get_attr_xmit_fifo_size
, NULL
);
2537 static DEVICE_ATTR(uartclk
, S_IRUSR
| S_IRGRP
, uart_get_attr_uartclk
, NULL
);
2538 static DEVICE_ATTR(close_delay
, S_IRUSR
| S_IRGRP
, uart_get_attr_close_delay
, NULL
);
2539 static DEVICE_ATTR(closing_wait
, S_IRUSR
| S_IRGRP
, uart_get_attr_closing_wait
, NULL
);
2540 static DEVICE_ATTR(custom_divisor
, S_IRUSR
| S_IRGRP
, uart_get_attr_custom_divisor
, NULL
);
2541 static DEVICE_ATTR(io_type
, S_IRUSR
| S_IRGRP
, uart_get_attr_io_type
, NULL
);
2542 static DEVICE_ATTR(iomem_base
, S_IRUSR
| S_IRGRP
, uart_get_attr_iomem_base
, NULL
);
2543 static DEVICE_ATTR(iomem_reg_shift
, S_IRUSR
| S_IRGRP
, uart_get_attr_iomem_reg_shift
, NULL
);
2545 static struct attribute
*tty_dev_attrs
[] = {
2546 &dev_attr_type
.attr
,
2547 &dev_attr_line
.attr
,
2548 &dev_attr_port
.attr
,
2550 &dev_attr_flags
.attr
,
2551 &dev_attr_xmit_fifo_size
.attr
,
2552 &dev_attr_uartclk
.attr
,
2553 &dev_attr_close_delay
.attr
,
2554 &dev_attr_closing_wait
.attr
,
2555 &dev_attr_custom_divisor
.attr
,
2556 &dev_attr_io_type
.attr
,
2557 &dev_attr_iomem_base
.attr
,
2558 &dev_attr_iomem_reg_shift
.attr
,
2562 static const struct attribute_group tty_dev_attr_group
= {
2563 .attrs
= tty_dev_attrs
,
2566 static const struct attribute_group
*tty_dev_attr_groups
[] = {
2567 &tty_dev_attr_group
,
2573 * uart_add_one_port - attach a driver-defined port structure
2574 * @drv: pointer to the uart low level driver structure for this port
2575 * @uport: uart port structure to use for this port.
2577 * This allows the driver to register its own uart_port structure
2578 * with the core driver. The main purpose is to allow the low
2579 * level uart drivers to expand uart_port, rather than having yet
2580 * more levels of structures.
2582 int uart_add_one_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2584 struct uart_state
*state
;
2585 struct tty_port
*port
;
2587 struct device
*tty_dev
;
2589 BUG_ON(in_interrupt());
2591 if (uport
->line
>= drv
->nr
)
2594 state
= drv
->state
+ uport
->line
;
2595 port
= &state
->port
;
2597 mutex_lock(&port_mutex
);
2598 mutex_lock(&port
->mutex
);
2599 if (state
->uart_port
) {
2604 state
->uart_port
= uport
;
2605 state
->pm_state
= UART_PM_STATE_UNDEFINED
;
2607 uport
->cons
= drv
->cons
;
2608 uport
->state
= state
;
2611 * If this port is a console, then the spinlock is already
2614 if (!(uart_console(uport
) && (uport
->cons
->flags
& CON_ENABLED
))) {
2615 spin_lock_init(&uport
->lock
);
2616 lockdep_set_class(&uport
->lock
, &port_lock_key
);
2619 uart_configure_port(drv
, state
, uport
);
2622 * Register the port whether it's detected or not. This allows
2623 * setserial to be used to alter this port's parameters.
2625 tty_dev
= tty_port_register_device_attr(port
, drv
->tty_driver
,
2626 uport
->line
, uport
->dev
, port
, tty_dev_attr_groups
);
2627 if (likely(!IS_ERR(tty_dev
))) {
2628 device_set_wakeup_capable(tty_dev
, 1);
2630 printk(KERN_ERR
"Cannot register tty device on line %d\n",
2635 * Ensure UPF_DEAD is not set.
2637 uport
->flags
&= ~UPF_DEAD
;
2640 mutex_unlock(&port
->mutex
);
2641 mutex_unlock(&port_mutex
);
2647 * uart_remove_one_port - detach a driver defined port structure
2648 * @drv: pointer to the uart low level driver structure for this port
2649 * @uport: uart port structure for this port
2651 * This unhooks (and hangs up) the specified port structure from the
2652 * core driver. No further calls will be made to the low-level code
2655 int uart_remove_one_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2657 struct uart_state
*state
= drv
->state
+ uport
->line
;
2658 struct tty_port
*port
= &state
->port
;
2659 struct tty_struct
*tty
;
2662 BUG_ON(in_interrupt());
2664 if (state
->uart_port
!= uport
)
2665 printk(KERN_ALERT
"Removing wrong port: %p != %p\n",
2666 state
->uart_port
, uport
);
2668 mutex_lock(&port_mutex
);
2671 * Mark the port "dead" - this prevents any opens from
2672 * succeeding while we shut down the port.
2674 mutex_lock(&port
->mutex
);
2675 if (!state
->uart_port
) {
2676 mutex_unlock(&port
->mutex
);
2680 uport
->flags
|= UPF_DEAD
;
2681 mutex_unlock(&port
->mutex
);
2684 * Remove the devices from the tty layer
2686 tty_unregister_device(drv
->tty_driver
, uport
->line
);
2688 tty
= tty_port_tty_get(port
);
2690 tty_vhangup(port
->tty
);
2695 * If the port is used as a console, unregister it
2697 if (uart_console(uport
))
2698 unregister_console(uport
->cons
);
2701 * Free the port IO and memory resources, if any.
2703 if (uport
->type
!= PORT_UNKNOWN
)
2704 uport
->ops
->release_port(uport
);
2707 * Indicate that there isn't a port here anymore.
2709 uport
->type
= PORT_UNKNOWN
;
2711 state
->uart_port
= NULL
;
2713 mutex_unlock(&port_mutex
);
2719 * Are the two ports equivalent?
2721 int uart_match_port(struct uart_port
*port1
, struct uart_port
*port2
)
2723 if (port1
->iotype
!= port2
->iotype
)
2726 switch (port1
->iotype
) {
2728 return (port1
->iobase
== port2
->iobase
);
2730 return (port1
->iobase
== port2
->iobase
) &&
2731 (port1
->hub6
== port2
->hub6
);
2736 return (port1
->mapbase
== port2
->mapbase
);
2740 EXPORT_SYMBOL(uart_match_port
);
2743 * uart_handle_dcd_change - handle a change of carrier detect state
2744 * @uport: uart_port structure for the open port
2745 * @status: new carrier detect status, nonzero if active
2747 void uart_handle_dcd_change(struct uart_port
*uport
, unsigned int status
)
2749 struct tty_port
*port
= &uport
->state
->port
;
2750 struct tty_struct
*tty
= port
->tty
;
2751 struct tty_ldisc
*ld
= tty
? tty_ldisc_ref(tty
) : NULL
;
2754 if (ld
->ops
->dcd_change
)
2755 ld
->ops
->dcd_change(tty
, status
);
2756 tty_ldisc_deref(ld
);
2759 uport
->icount
.dcd
++;
2761 if (port
->flags
& ASYNC_CHECK_CD
) {
2763 wake_up_interruptible(&port
->open_wait
);
2768 EXPORT_SYMBOL_GPL(uart_handle_dcd_change
);
2771 * uart_handle_cts_change - handle a change of clear-to-send state
2772 * @uport: uart_port structure for the open port
2773 * @status: new clear to send status, nonzero if active
2775 void uart_handle_cts_change(struct uart_port
*uport
, unsigned int status
)
2777 struct tty_port
*port
= &uport
->state
->port
;
2778 struct tty_struct
*tty
= port
->tty
;
2780 uport
->icount
.cts
++;
2782 /* skip below code if the hw flow control is supported */
2783 if (tty_port_cts_enabled(port
) &&
2784 !(uport
->flags
& UPF_HARD_FLOW
)) {
2785 if (tty
->hw_stopped
) {
2787 tty
->hw_stopped
= 0;
2788 uport
->ops
->start_tx(uport
);
2789 uart_write_wakeup(uport
);
2793 tty
->hw_stopped
= 1;
2794 uport
->ops
->stop_tx(uport
);
2799 EXPORT_SYMBOL_GPL(uart_handle_cts_change
);
2802 * uart_insert_char - push a char to the uart layer
2804 * User is responsible to call tty_flip_buffer_push when they are done with
2807 * @port: corresponding port
2808 * @status: state of the serial port RX buffer (LSR for 8250)
2809 * @overrun: mask of overrun bits in @status
2810 * @ch: character to push
2811 * @flag: flag for the character (see TTY_NORMAL and friends)
2813 void uart_insert_char(struct uart_port
*port
, unsigned int status
,
2814 unsigned int overrun
, unsigned int ch
, unsigned int flag
)
2816 struct tty_port
*tport
= &port
->state
->port
;
2818 if ((status
& port
->ignore_status_mask
& ~overrun
) == 0)
2819 if (tty_insert_flip_char(tport
, ch
, flag
) == 0)
2820 ++port
->icount
.buf_overrun
;
2823 * Overrun is special. Since it's reported immediately,
2824 * it doesn't affect the current character.
2826 if (status
& ~port
->ignore_status_mask
& overrun
)
2827 if (tty_insert_flip_char(tport
, 0, TTY_OVERRUN
) == 0)
2828 ++port
->icount
.buf_overrun
;
2830 EXPORT_SYMBOL_GPL(uart_insert_char
);
2832 EXPORT_SYMBOL(uart_write_wakeup
);
2833 EXPORT_SYMBOL(uart_register_driver
);
2834 EXPORT_SYMBOL(uart_unregister_driver
);
2835 EXPORT_SYMBOL(uart_suspend_port
);
2836 EXPORT_SYMBOL(uart_resume_port
);
2837 EXPORT_SYMBOL(uart_add_one_port
);
2838 EXPORT_SYMBOL(uart_remove_one_port
);
2840 MODULE_DESCRIPTION("Serial driver core");
2841 MODULE_LICENSE("GPL");