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/sched/signal.h>
28 #include <linux/init.h>
29 #include <linux/console.h>
31 #include <linux/proc_fs.h>
32 #include <linux/seq_file.h>
33 #include <linux/device.h>
34 #include <linux/serial.h> /* for serial_state and serial_icounter_struct */
35 #include <linux/serial_core.h>
36 #include <linux/delay.h>
37 #include <linux/mutex.h>
40 #include <linux/uaccess.h>
43 * This is used to lock changes in serial line configuration.
45 static DEFINE_MUTEX(port_mutex
);
48 * lockdep: port->lock is initialized in two places, but we
49 * want only one lock-class:
51 static struct lock_class_key port_lock_key
;
53 #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
55 static void uart_change_speed(struct tty_struct
*tty
, struct uart_state
*state
,
56 struct ktermios
*old_termios
);
57 static void uart_wait_until_sent(struct tty_struct
*tty
, int timeout
);
58 static void uart_change_pm(struct uart_state
*state
,
59 enum uart_pm_state pm_state
);
61 static void uart_port_shutdown(struct tty_port
*port
);
63 static int uart_dcd_enabled(struct uart_port
*uport
)
65 return !!(uport
->status
& UPSTAT_DCD_ENABLE
);
68 static inline struct uart_port
*uart_port_ref(struct uart_state
*state
)
70 if (atomic_add_unless(&state
->refcount
, 1, 0))
71 return state
->uart_port
;
75 static inline void uart_port_deref(struct uart_port
*uport
)
77 if (atomic_dec_and_test(&uport
->state
->refcount
))
78 wake_up(&uport
->state
->remove_wait
);
81 #define uart_port_lock(state, flags) \
83 struct uart_port *__uport = uart_port_ref(state); \
85 spin_lock_irqsave(&__uport->lock, flags); \
89 #define uart_port_unlock(uport, flags) \
91 struct uart_port *__uport = uport; \
93 spin_unlock_irqrestore(&__uport->lock, flags); \
94 uart_port_deref(__uport); \
98 static inline struct uart_port
*uart_port_check(struct uart_state
*state
)
100 lockdep_assert_held(&state
->port
.mutex
);
101 return state
->uart_port
;
105 * This routine is used by the interrupt handler to schedule processing in
106 * the software interrupt portion of the driver.
108 void uart_write_wakeup(struct uart_port
*port
)
110 struct uart_state
*state
= port
->state
;
112 * This means you called this function _after_ the port was
113 * closed. No cookie for you.
116 tty_port_tty_wakeup(&state
->port
);
119 static void uart_stop(struct tty_struct
*tty
)
121 struct uart_state
*state
= tty
->driver_data
;
122 struct uart_port
*port
;
125 port
= uart_port_lock(state
, flags
);
127 port
->ops
->stop_tx(port
);
128 uart_port_unlock(port
, flags
);
131 static void __uart_start(struct tty_struct
*tty
)
133 struct uart_state
*state
= tty
->driver_data
;
134 struct uart_port
*port
= state
->uart_port
;
136 if (port
&& !uart_tx_stopped(port
))
137 port
->ops
->start_tx(port
);
140 static void uart_start(struct tty_struct
*tty
)
142 struct uart_state
*state
= tty
->driver_data
;
143 struct uart_port
*port
;
146 port
= uart_port_lock(state
, flags
);
148 uart_port_unlock(port
, flags
);
152 uart_update_mctrl(struct uart_port
*port
, unsigned int set
, unsigned int clear
)
157 spin_lock_irqsave(&port
->lock
, flags
);
159 port
->mctrl
= (old
& ~clear
) | set
;
160 if (old
!= port
->mctrl
)
161 port
->ops
->set_mctrl(port
, port
->mctrl
);
162 spin_unlock_irqrestore(&port
->lock
, flags
);
165 #define uart_set_mctrl(port, set) uart_update_mctrl(port, set, 0)
166 #define uart_clear_mctrl(port, clear) uart_update_mctrl(port, 0, clear)
169 * Startup the port. This will be called once per open. All calls
170 * will be serialised by the per-port mutex.
172 static int uart_port_startup(struct tty_struct
*tty
, struct uart_state
*state
,
175 struct uart_port
*uport
= uart_port_check(state
);
179 if (uport
->type
== PORT_UNKNOWN
)
183 * Make sure the device is in D0 state.
185 uart_change_pm(state
, UART_PM_STATE_ON
);
188 * Initialise and allocate the transmit and temporary
191 if (!state
->xmit
.buf
) {
192 /* This is protected by the per port mutex */
193 page
= get_zeroed_page(GFP_KERNEL
);
197 state
->xmit
.buf
= (unsigned char *) page
;
198 uart_circ_clear(&state
->xmit
);
201 retval
= uport
->ops
->startup(uport
);
203 if (uart_console(uport
) && uport
->cons
->cflag
) {
204 tty
->termios
.c_cflag
= uport
->cons
->cflag
;
205 uport
->cons
->cflag
= 0;
208 * Initialise the hardware port settings.
210 uart_change_speed(tty
, state
, NULL
);
213 * Setup the RTS and DTR signals once the
214 * port is open and ready to respond.
216 if (init_hw
&& C_BAUD(tty
))
217 uart_set_mctrl(uport
, TIOCM_RTS
| TIOCM_DTR
);
221 * This is to allow setserial on this port. People may want to set
222 * port/irq/type and then reconfigure the port properly if it failed
225 if (retval
&& capable(CAP_SYS_ADMIN
))
231 static int uart_startup(struct tty_struct
*tty
, struct uart_state
*state
,
234 struct tty_port
*port
= &state
->port
;
237 if (tty_port_initialized(port
))
240 retval
= uart_port_startup(tty
, state
, init_hw
);
242 set_bit(TTY_IO_ERROR
, &tty
->flags
);
248 * This routine will shutdown a serial port; interrupts are disabled, and
249 * DTR is dropped if the hangup on close termio flag is on. Calls to
250 * uart_shutdown are serialised by the per-port semaphore.
252 * uport == NULL if uart_port has already been removed
254 static void uart_shutdown(struct tty_struct
*tty
, struct uart_state
*state
)
256 struct uart_port
*uport
= uart_port_check(state
);
257 struct tty_port
*port
= &state
->port
;
260 * Set the TTY IO error marker
263 set_bit(TTY_IO_ERROR
, &tty
->flags
);
265 if (tty_port_initialized(port
)) {
266 tty_port_set_initialized(port
, 0);
269 * Turn off DTR and RTS early.
271 if (uport
&& uart_console(uport
) && tty
)
272 uport
->cons
->cflag
= tty
->termios
.c_cflag
;
274 if (!tty
|| C_HUPCL(tty
))
275 uart_clear_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
277 uart_port_shutdown(port
);
281 * It's possible for shutdown to be called after suspend if we get
282 * a DCD drop (hangup) at just the right time. Clear suspended bit so
283 * we don't try to resume a port that has been shutdown.
285 tty_port_set_suspended(port
, 0);
288 * Free the transmit buffer page.
290 if (state
->xmit
.buf
) {
291 free_page((unsigned long)state
->xmit
.buf
);
292 state
->xmit
.buf
= NULL
;
297 * uart_update_timeout - update per-port FIFO timeout.
298 * @port: uart_port structure describing the port
299 * @cflag: termios cflag value
300 * @baud: speed of the port
302 * Set the port FIFO timeout value. The @cflag value should
303 * reflect the actual hardware settings.
306 uart_update_timeout(struct uart_port
*port
, unsigned int cflag
,
311 /* byte size and parity */
312 switch (cflag
& CSIZE
) {
333 * The total number of bits to be transmitted in the fifo.
335 bits
= bits
* port
->fifosize
;
338 * Figure the timeout to send the above number of bits.
339 * Add .02 seconds of slop
341 port
->timeout
= (HZ
* bits
) / baud
+ HZ
/50;
344 EXPORT_SYMBOL(uart_update_timeout
);
347 * uart_get_baud_rate - return baud rate for a particular port
348 * @port: uart_port structure describing the port in question.
349 * @termios: desired termios settings.
350 * @old: old termios (or NULL)
351 * @min: minimum acceptable baud rate
352 * @max: maximum acceptable baud rate
354 * Decode the termios structure into a numeric baud rate,
355 * taking account of the magic 38400 baud rate (with spd_*
356 * flags), and mapping the %B0 rate to 9600 baud.
358 * If the new baud rate is invalid, try the old termios setting.
359 * If it's still invalid, we try 9600 baud.
361 * Update the @termios structure to reflect the baud rate
362 * we're actually going to be using. Don't do this for the case
363 * where B0 is requested ("hang up").
366 uart_get_baud_rate(struct uart_port
*port
, struct ktermios
*termios
,
367 struct ktermios
*old
, unsigned int min
, unsigned int max
)
371 unsigned int altbaud
;
373 upf_t flags
= port
->flags
& UPF_SPD_MASK
;
393 for (try = 0; try < 2; try++) {
394 baud
= tty_termios_baud_rate(termios
);
397 * The spd_hi, spd_vhi, spd_shi, spd_warp kludge...
400 if (try == 0 && baud
== 38400)
404 * Special case: B0 rate.
411 if (baud
>= min
&& baud
<= max
)
415 * Oops, the quotient was zero. Try again with
416 * the old baud rate if possible.
418 termios
->c_cflag
&= ~CBAUD
;
420 baud
= tty_termios_baud_rate(old
);
422 tty_termios_encode_baud_rate(termios
,
429 * As a last resort, if the range cannot be met then clip to
430 * the nearest chip supported rate.
434 tty_termios_encode_baud_rate(termios
,
437 tty_termios_encode_baud_rate(termios
,
441 /* Should never happen */
446 EXPORT_SYMBOL(uart_get_baud_rate
);
449 * uart_get_divisor - return uart clock divisor
450 * @port: uart_port structure describing the port.
451 * @baud: desired baud rate
453 * Calculate the uart clock divisor for the port.
456 uart_get_divisor(struct uart_port
*port
, unsigned int baud
)
461 * Old custom speed handling.
463 if (baud
== 38400 && (port
->flags
& UPF_SPD_MASK
) == UPF_SPD_CUST
)
464 quot
= port
->custom_divisor
;
466 quot
= DIV_ROUND_CLOSEST(port
->uartclk
, 16 * baud
);
471 EXPORT_SYMBOL(uart_get_divisor
);
473 /* Caller holds port mutex */
474 static void uart_change_speed(struct tty_struct
*tty
, struct uart_state
*state
,
475 struct ktermios
*old_termios
)
477 struct uart_port
*uport
= uart_port_check(state
);
478 struct ktermios
*termios
;
482 * If we have no tty, termios, or the port does not exist,
483 * then we can't set the parameters for this port.
485 if (!tty
|| uport
->type
== PORT_UNKNOWN
)
488 termios
= &tty
->termios
;
489 uport
->ops
->set_termios(uport
, termios
, old_termios
);
492 * Set modem status enables based on termios cflag
494 spin_lock_irq(&uport
->lock
);
495 if (termios
->c_cflag
& CRTSCTS
)
496 uport
->status
|= UPSTAT_CTS_ENABLE
;
498 uport
->status
&= ~UPSTAT_CTS_ENABLE
;
500 if (termios
->c_cflag
& CLOCAL
)
501 uport
->status
&= ~UPSTAT_DCD_ENABLE
;
503 uport
->status
|= UPSTAT_DCD_ENABLE
;
505 /* reset sw-assisted CTS flow control based on (possibly) new mode */
506 hw_stopped
= uport
->hw_stopped
;
507 uport
->hw_stopped
= uart_softcts_mode(uport
) &&
508 !(uport
->ops
->get_mctrl(uport
) & TIOCM_CTS
);
509 if (uport
->hw_stopped
) {
511 uport
->ops
->stop_tx(uport
);
516 spin_unlock_irq(&uport
->lock
);
519 static int uart_put_char(struct tty_struct
*tty
, unsigned char c
)
521 struct uart_state
*state
= tty
->driver_data
;
522 struct uart_port
*port
;
523 struct circ_buf
*circ
;
531 port
= uart_port_lock(state
, flags
);
532 if (port
&& uart_circ_chars_free(circ
) != 0) {
533 circ
->buf
[circ
->head
] = c
;
534 circ
->head
= (circ
->head
+ 1) & (UART_XMIT_SIZE
- 1);
537 uart_port_unlock(port
, flags
);
541 static void uart_flush_chars(struct tty_struct
*tty
)
546 static int uart_write(struct tty_struct
*tty
,
547 const unsigned char *buf
, int count
)
549 struct uart_state
*state
= tty
->driver_data
;
550 struct uart_port
*port
;
551 struct circ_buf
*circ
;
556 * This means you called this function _after_ the port was
557 * closed. No cookie for you.
568 port
= uart_port_lock(state
, flags
);
570 c
= CIRC_SPACE_TO_END(circ
->head
, circ
->tail
, UART_XMIT_SIZE
);
575 memcpy(circ
->buf
+ circ
->head
, buf
, c
);
576 circ
->head
= (circ
->head
+ c
) & (UART_XMIT_SIZE
- 1);
583 uart_port_unlock(port
, flags
);
587 static int uart_write_room(struct tty_struct
*tty
)
589 struct uart_state
*state
= tty
->driver_data
;
590 struct uart_port
*port
;
594 port
= uart_port_lock(state
, flags
);
595 ret
= uart_circ_chars_free(&state
->xmit
);
596 uart_port_unlock(port
, flags
);
600 static int uart_chars_in_buffer(struct tty_struct
*tty
)
602 struct uart_state
*state
= tty
->driver_data
;
603 struct uart_port
*port
;
607 port
= uart_port_lock(state
, flags
);
608 ret
= uart_circ_chars_pending(&state
->xmit
);
609 uart_port_unlock(port
, flags
);
613 static void uart_flush_buffer(struct tty_struct
*tty
)
615 struct uart_state
*state
= tty
->driver_data
;
616 struct uart_port
*port
;
620 * This means you called this function _after_ the port was
621 * closed. No cookie for you.
628 pr_debug("uart_flush_buffer(%d) called\n", tty
->index
);
630 port
= uart_port_lock(state
, flags
);
633 uart_circ_clear(&state
->xmit
);
634 if (port
->ops
->flush_buffer
)
635 port
->ops
->flush_buffer(port
);
636 uart_port_unlock(port
, flags
);
637 tty_port_tty_wakeup(&state
->port
);
641 * This function is used to send a high-priority XON/XOFF character to
644 static void uart_send_xchar(struct tty_struct
*tty
, char ch
)
646 struct uart_state
*state
= tty
->driver_data
;
647 struct uart_port
*port
;
650 port
= uart_port_ref(state
);
654 if (port
->ops
->send_xchar
)
655 port
->ops
->send_xchar(port
, ch
);
657 spin_lock_irqsave(&port
->lock
, flags
);
660 port
->ops
->start_tx(port
);
661 spin_unlock_irqrestore(&port
->lock
, flags
);
663 uart_port_deref(port
);
666 static void uart_throttle(struct tty_struct
*tty
)
668 struct uart_state
*state
= tty
->driver_data
;
669 struct uart_port
*port
;
672 port
= uart_port_ref(state
);
677 mask
|= UPSTAT_AUTOXOFF
;
679 mask
|= UPSTAT_AUTORTS
;
681 if (port
->status
& mask
) {
682 port
->ops
->throttle(port
);
683 mask
&= ~port
->status
;
686 if (mask
& UPSTAT_AUTORTS
)
687 uart_clear_mctrl(port
, TIOCM_RTS
);
689 if (mask
& UPSTAT_AUTOXOFF
)
690 uart_send_xchar(tty
, STOP_CHAR(tty
));
692 uart_port_deref(port
);
695 static void uart_unthrottle(struct tty_struct
*tty
)
697 struct uart_state
*state
= tty
->driver_data
;
698 struct uart_port
*port
;
701 port
= uart_port_ref(state
);
706 mask
|= UPSTAT_AUTOXOFF
;
708 mask
|= UPSTAT_AUTORTS
;
710 if (port
->status
& mask
) {
711 port
->ops
->unthrottle(port
);
712 mask
&= ~port
->status
;
715 if (mask
& UPSTAT_AUTORTS
)
716 uart_set_mctrl(port
, TIOCM_RTS
);
718 if (mask
& UPSTAT_AUTOXOFF
)
719 uart_send_xchar(tty
, START_CHAR(tty
));
721 uart_port_deref(port
);
724 static int uart_get_info(struct tty_port
*port
, struct serial_struct
*retinfo
)
726 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
727 struct uart_port
*uport
;
730 memset(retinfo
, 0, sizeof(*retinfo
));
733 * Ensure the state we copy is consistent and no hardware changes
736 mutex_lock(&port
->mutex
);
737 uport
= uart_port_check(state
);
741 retinfo
->type
= uport
->type
;
742 retinfo
->line
= uport
->line
;
743 retinfo
->port
= uport
->iobase
;
744 if (HIGH_BITS_OFFSET
)
745 retinfo
->port_high
= (long) uport
->iobase
>> HIGH_BITS_OFFSET
;
746 retinfo
->irq
= uport
->irq
;
747 retinfo
->flags
= uport
->flags
;
748 retinfo
->xmit_fifo_size
= uport
->fifosize
;
749 retinfo
->baud_base
= uport
->uartclk
/ 16;
750 retinfo
->close_delay
= jiffies_to_msecs(port
->close_delay
) / 10;
751 retinfo
->closing_wait
= port
->closing_wait
== ASYNC_CLOSING_WAIT_NONE
?
752 ASYNC_CLOSING_WAIT_NONE
:
753 jiffies_to_msecs(port
->closing_wait
) / 10;
754 retinfo
->custom_divisor
= uport
->custom_divisor
;
755 retinfo
->hub6
= uport
->hub6
;
756 retinfo
->io_type
= uport
->iotype
;
757 retinfo
->iomem_reg_shift
= uport
->regshift
;
758 retinfo
->iomem_base
= (void *)(unsigned long)uport
->mapbase
;
762 mutex_unlock(&port
->mutex
);
766 static int uart_get_info_user(struct tty_port
*port
,
767 struct serial_struct __user
*retinfo
)
769 struct serial_struct tmp
;
771 if (uart_get_info(port
, &tmp
) < 0)
774 if (copy_to_user(retinfo
, &tmp
, sizeof(*retinfo
)))
779 static int uart_set_info(struct tty_struct
*tty
, struct tty_port
*port
,
780 struct uart_state
*state
,
781 struct serial_struct
*new_info
)
783 struct uart_port
*uport
= uart_port_check(state
);
784 unsigned long new_port
;
785 unsigned int change_irq
, change_port
, closing_wait
;
786 unsigned int old_custom_divisor
, close_delay
;
787 upf_t old_flags
, new_flags
;
793 new_port
= new_info
->port
;
794 if (HIGH_BITS_OFFSET
)
795 new_port
+= (unsigned long) new_info
->port_high
<< HIGH_BITS_OFFSET
;
797 new_info
->irq
= irq_canonicalize(new_info
->irq
);
798 close_delay
= msecs_to_jiffies(new_info
->close_delay
* 10);
799 closing_wait
= new_info
->closing_wait
== ASYNC_CLOSING_WAIT_NONE
?
800 ASYNC_CLOSING_WAIT_NONE
:
801 msecs_to_jiffies(new_info
->closing_wait
* 10);
804 change_irq
= !(uport
->flags
& UPF_FIXED_PORT
)
805 && new_info
->irq
!= uport
->irq
;
808 * Since changing the 'type' of the port changes its resource
809 * allocations, we should treat type changes the same as
812 change_port
= !(uport
->flags
& UPF_FIXED_PORT
)
813 && (new_port
!= uport
->iobase
||
814 (unsigned long)new_info
->iomem_base
!= uport
->mapbase
||
815 new_info
->hub6
!= uport
->hub6
||
816 new_info
->io_type
!= uport
->iotype
||
817 new_info
->iomem_reg_shift
!= uport
->regshift
||
818 new_info
->type
!= uport
->type
);
820 old_flags
= uport
->flags
;
821 new_flags
= new_info
->flags
;
822 old_custom_divisor
= uport
->custom_divisor
;
824 if (!capable(CAP_SYS_ADMIN
)) {
826 if (change_irq
|| change_port
||
827 (new_info
->baud_base
!= uport
->uartclk
/ 16) ||
828 (close_delay
!= port
->close_delay
) ||
829 (closing_wait
!= port
->closing_wait
) ||
830 (new_info
->xmit_fifo_size
&&
831 new_info
->xmit_fifo_size
!= uport
->fifosize
) ||
832 (((new_flags
^ old_flags
) & ~UPF_USR_MASK
) != 0))
834 uport
->flags
= ((uport
->flags
& ~UPF_USR_MASK
) |
835 (new_flags
& UPF_USR_MASK
));
836 uport
->custom_divisor
= new_info
->custom_divisor
;
841 * Ask the low level driver to verify the settings.
843 if (uport
->ops
->verify_port
)
844 retval
= uport
->ops
->verify_port(uport
, new_info
);
846 if ((new_info
->irq
>= nr_irqs
) || (new_info
->irq
< 0) ||
847 (new_info
->baud_base
< 9600))
853 if (change_port
|| change_irq
) {
857 * Make sure that we are the sole user of this port.
859 if (tty_port_users(port
) > 1)
863 * We need to shutdown the serial port at the old
864 * port/type/irq combination.
866 uart_shutdown(tty
, state
);
870 unsigned long old_iobase
, old_mapbase
;
871 unsigned int old_type
, old_iotype
, old_hub6
, old_shift
;
873 old_iobase
= uport
->iobase
;
874 old_mapbase
= uport
->mapbase
;
875 old_type
= uport
->type
;
876 old_hub6
= uport
->hub6
;
877 old_iotype
= uport
->iotype
;
878 old_shift
= uport
->regshift
;
881 * Free and release old regions
883 if (old_type
!= PORT_UNKNOWN
&& uport
->ops
->release_port
)
884 uport
->ops
->release_port(uport
);
886 uport
->iobase
= new_port
;
887 uport
->type
= new_info
->type
;
888 uport
->hub6
= new_info
->hub6
;
889 uport
->iotype
= new_info
->io_type
;
890 uport
->regshift
= new_info
->iomem_reg_shift
;
891 uport
->mapbase
= (unsigned long)new_info
->iomem_base
;
894 * Claim and map the new regions
896 if (uport
->type
!= PORT_UNKNOWN
&& uport
->ops
->request_port
) {
897 retval
= uport
->ops
->request_port(uport
);
899 /* Always success - Jean II */
904 * If we fail to request resources for the
905 * new port, try to restore the old settings.
908 uport
->iobase
= old_iobase
;
909 uport
->type
= old_type
;
910 uport
->hub6
= old_hub6
;
911 uport
->iotype
= old_iotype
;
912 uport
->regshift
= old_shift
;
913 uport
->mapbase
= old_mapbase
;
915 if (old_type
!= PORT_UNKNOWN
) {
916 retval
= uport
->ops
->request_port(uport
);
918 * If we failed to restore the old settings,
922 uport
->type
= PORT_UNKNOWN
;
930 /* Added to return the correct error -Ram Gupta */
936 uport
->irq
= new_info
->irq
;
937 if (!(uport
->flags
& UPF_FIXED_PORT
))
938 uport
->uartclk
= new_info
->baud_base
* 16;
939 uport
->flags
= (uport
->flags
& ~UPF_CHANGE_MASK
) |
940 (new_flags
& UPF_CHANGE_MASK
);
941 uport
->custom_divisor
= new_info
->custom_divisor
;
942 port
->close_delay
= close_delay
;
943 port
->closing_wait
= closing_wait
;
944 if (new_info
->xmit_fifo_size
)
945 uport
->fifosize
= new_info
->xmit_fifo_size
;
946 port
->low_latency
= (uport
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
950 if (uport
->type
== PORT_UNKNOWN
)
952 if (tty_port_initialized(port
)) {
953 if (((old_flags
^ uport
->flags
) & UPF_SPD_MASK
) ||
954 old_custom_divisor
!= uport
->custom_divisor
) {
956 * If they're setting up a custom divisor or speed,
957 * instead of clearing it, then bitch about it. No
958 * need to rate-limit; it's CAP_SYS_ADMIN only.
960 if (uport
->flags
& UPF_SPD_MASK
) {
961 dev_notice(uport
->dev
,
962 "%s sets custom speed on %s. This is deprecated.\n",
964 tty_name(port
->tty
));
966 uart_change_speed(tty
, state
, NULL
);
969 retval
= uart_startup(tty
, state
, 1);
977 static int uart_set_info_user(struct tty_struct
*tty
, struct uart_state
*state
,
978 struct serial_struct __user
*newinfo
)
980 struct serial_struct new_serial
;
981 struct tty_port
*port
= &state
->port
;
984 if (copy_from_user(&new_serial
, newinfo
, sizeof(new_serial
)))
988 * This semaphore protects port->count. It is also
989 * very useful to prevent opens. Also, take the
990 * port configuration semaphore to make sure that a
991 * module insertion/removal doesn't change anything
994 mutex_lock(&port
->mutex
);
995 retval
= uart_set_info(tty
, port
, state
, &new_serial
);
996 mutex_unlock(&port
->mutex
);
1001 * uart_get_lsr_info - get line status register info
1002 * @tty: tty associated with the UART
1003 * @state: UART being queried
1004 * @value: returned modem value
1006 static int uart_get_lsr_info(struct tty_struct
*tty
,
1007 struct uart_state
*state
, unsigned int __user
*value
)
1009 struct uart_port
*uport
= uart_port_check(state
);
1010 unsigned int result
;
1012 result
= uport
->ops
->tx_empty(uport
);
1015 * If we're about to load something into the transmit
1016 * register, we'll pretend the transmitter isn't empty to
1017 * avoid a race condition (depending on when the transmit
1018 * interrupt happens).
1020 if (uport
->x_char
||
1021 ((uart_circ_chars_pending(&state
->xmit
) > 0) &&
1022 !uart_tx_stopped(uport
)))
1023 result
&= ~TIOCSER_TEMT
;
1025 return put_user(result
, value
);
1028 static int uart_tiocmget(struct tty_struct
*tty
)
1030 struct uart_state
*state
= tty
->driver_data
;
1031 struct tty_port
*port
= &state
->port
;
1032 struct uart_port
*uport
;
1035 mutex_lock(&port
->mutex
);
1036 uport
= uart_port_check(state
);
1040 if (!tty_io_error(tty
)) {
1041 result
= uport
->mctrl
;
1042 spin_lock_irq(&uport
->lock
);
1043 result
|= uport
->ops
->get_mctrl(uport
);
1044 spin_unlock_irq(&uport
->lock
);
1047 mutex_unlock(&port
->mutex
);
1052 uart_tiocmset(struct tty_struct
*tty
, unsigned int set
, unsigned int clear
)
1054 struct uart_state
*state
= tty
->driver_data
;
1055 struct tty_port
*port
= &state
->port
;
1056 struct uart_port
*uport
;
1059 mutex_lock(&port
->mutex
);
1060 uport
= uart_port_check(state
);
1064 if (!tty_io_error(tty
)) {
1065 uart_update_mctrl(uport
, set
, clear
);
1069 mutex_unlock(&port
->mutex
);
1073 static int uart_break_ctl(struct tty_struct
*tty
, int break_state
)
1075 struct uart_state
*state
= tty
->driver_data
;
1076 struct tty_port
*port
= &state
->port
;
1077 struct uart_port
*uport
;
1080 mutex_lock(&port
->mutex
);
1081 uport
= uart_port_check(state
);
1085 if (uport
->type
!= PORT_UNKNOWN
)
1086 uport
->ops
->break_ctl(uport
, break_state
);
1089 mutex_unlock(&port
->mutex
);
1093 static int uart_do_autoconfig(struct tty_struct
*tty
,struct uart_state
*state
)
1095 struct tty_port
*port
= &state
->port
;
1096 struct uart_port
*uport
;
1099 if (!capable(CAP_SYS_ADMIN
))
1103 * Take the per-port semaphore. This prevents count from
1104 * changing, and hence any extra opens of the port while
1105 * we're auto-configuring.
1107 if (mutex_lock_interruptible(&port
->mutex
))
1108 return -ERESTARTSYS
;
1110 uport
= uart_port_check(state
);
1117 if (tty_port_users(port
) == 1) {
1118 uart_shutdown(tty
, state
);
1121 * If we already have a port type configured,
1122 * we must release its resources.
1124 if (uport
->type
!= PORT_UNKNOWN
&& uport
->ops
->release_port
)
1125 uport
->ops
->release_port(uport
);
1127 flags
= UART_CONFIG_TYPE
;
1128 if (uport
->flags
& UPF_AUTO_IRQ
)
1129 flags
|= UART_CONFIG_IRQ
;
1132 * This will claim the ports resources if
1135 uport
->ops
->config_port(uport
, flags
);
1137 ret
= uart_startup(tty
, state
, 1);
1142 mutex_unlock(&port
->mutex
);
1146 static void uart_enable_ms(struct uart_port
*uport
)
1149 * Force modem status interrupts on
1151 if (uport
->ops
->enable_ms
)
1152 uport
->ops
->enable_ms(uport
);
1156 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
1157 * - mask passed in arg for lines of interest
1158 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
1159 * Caller should use TIOCGICOUNT to see which one it was
1161 * FIXME: This wants extracting into a common all driver implementation
1162 * of TIOCMWAIT using tty_port.
1164 static int uart_wait_modem_status(struct uart_state
*state
, unsigned long arg
)
1166 struct uart_port
*uport
;
1167 struct tty_port
*port
= &state
->port
;
1168 DECLARE_WAITQUEUE(wait
, current
);
1169 struct uart_icount cprev
, cnow
;
1173 * note the counters on entry
1175 uport
= uart_port_ref(state
);
1178 spin_lock_irq(&uport
->lock
);
1179 memcpy(&cprev
, &uport
->icount
, sizeof(struct uart_icount
));
1180 uart_enable_ms(uport
);
1181 spin_unlock_irq(&uport
->lock
);
1183 add_wait_queue(&port
->delta_msr_wait
, &wait
);
1185 spin_lock_irq(&uport
->lock
);
1186 memcpy(&cnow
, &uport
->icount
, sizeof(struct uart_icount
));
1187 spin_unlock_irq(&uport
->lock
);
1189 set_current_state(TASK_INTERRUPTIBLE
);
1191 if (((arg
& TIOCM_RNG
) && (cnow
.rng
!= cprev
.rng
)) ||
1192 ((arg
& TIOCM_DSR
) && (cnow
.dsr
!= cprev
.dsr
)) ||
1193 ((arg
& TIOCM_CD
) && (cnow
.dcd
!= cprev
.dcd
)) ||
1194 ((arg
& TIOCM_CTS
) && (cnow
.cts
!= cprev
.cts
))) {
1201 /* see if a signal did it */
1202 if (signal_pending(current
)) {
1209 __set_current_state(TASK_RUNNING
);
1210 remove_wait_queue(&port
->delta_msr_wait
, &wait
);
1211 uart_port_deref(uport
);
1217 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1218 * Return: write counters to the user passed counter struct
1219 * NB: both 1->0 and 0->1 transitions are counted except for
1220 * RI where only 0->1 is counted.
1222 static int uart_get_icount(struct tty_struct
*tty
,
1223 struct serial_icounter_struct
*icount
)
1225 struct uart_state
*state
= tty
->driver_data
;
1226 struct uart_icount cnow
;
1227 struct uart_port
*uport
;
1229 uport
= uart_port_ref(state
);
1232 spin_lock_irq(&uport
->lock
);
1233 memcpy(&cnow
, &uport
->icount
, sizeof(struct uart_icount
));
1234 spin_unlock_irq(&uport
->lock
);
1235 uart_port_deref(uport
);
1237 icount
->cts
= cnow
.cts
;
1238 icount
->dsr
= cnow
.dsr
;
1239 icount
->rng
= cnow
.rng
;
1240 icount
->dcd
= cnow
.dcd
;
1241 icount
->rx
= cnow
.rx
;
1242 icount
->tx
= cnow
.tx
;
1243 icount
->frame
= cnow
.frame
;
1244 icount
->overrun
= cnow
.overrun
;
1245 icount
->parity
= cnow
.parity
;
1246 icount
->brk
= cnow
.brk
;
1247 icount
->buf_overrun
= cnow
.buf_overrun
;
1252 static int uart_get_rs485_config(struct uart_port
*port
,
1253 struct serial_rs485 __user
*rs485
)
1255 unsigned long flags
;
1256 struct serial_rs485 aux
;
1258 spin_lock_irqsave(&port
->lock
, flags
);
1260 spin_unlock_irqrestore(&port
->lock
, flags
);
1262 if (copy_to_user(rs485
, &aux
, sizeof(aux
)))
1268 static int uart_set_rs485_config(struct uart_port
*port
,
1269 struct serial_rs485 __user
*rs485_user
)
1271 struct serial_rs485 rs485
;
1273 unsigned long flags
;
1275 if (!port
->rs485_config
)
1276 return -ENOIOCTLCMD
;
1278 if (copy_from_user(&rs485
, rs485_user
, sizeof(*rs485_user
)))
1281 spin_lock_irqsave(&port
->lock
, flags
);
1282 ret
= port
->rs485_config(port
, &rs485
);
1283 spin_unlock_irqrestore(&port
->lock
, flags
);
1287 if (copy_to_user(rs485_user
, &port
->rs485
, sizeof(port
->rs485
)))
1294 * Called via sys_ioctl. We can use spin_lock_irq() here.
1297 uart_ioctl(struct tty_struct
*tty
, unsigned int cmd
, unsigned long arg
)
1299 struct uart_state
*state
= tty
->driver_data
;
1300 struct tty_port
*port
= &state
->port
;
1301 struct uart_port
*uport
;
1302 void __user
*uarg
= (void __user
*)arg
;
1303 int ret
= -ENOIOCTLCMD
;
1307 * These ioctls don't rely on the hardware to be present.
1311 ret
= uart_get_info_user(port
, uarg
);
1315 down_write(&tty
->termios_rwsem
);
1316 ret
= uart_set_info_user(tty
, state
, uarg
);
1317 up_write(&tty
->termios_rwsem
);
1321 down_write(&tty
->termios_rwsem
);
1322 ret
= uart_do_autoconfig(tty
, state
);
1323 up_write(&tty
->termios_rwsem
);
1326 case TIOCSERGWILD
: /* obsolete */
1327 case TIOCSERSWILD
: /* obsolete */
1332 if (ret
!= -ENOIOCTLCMD
)
1335 if (tty_io_error(tty
)) {
1341 * The following should only be used when hardware is present.
1345 ret
= uart_wait_modem_status(state
, arg
);
1349 if (ret
!= -ENOIOCTLCMD
)
1352 mutex_lock(&port
->mutex
);
1353 uport
= uart_port_check(state
);
1355 if (!uport
|| tty_io_error(tty
)) {
1361 * All these rely on hardware being present and need to be
1362 * protected against the tty being hung up.
1366 case TIOCSERGETLSR
: /* Get line status register */
1367 ret
= uart_get_lsr_info(tty
, state
, uarg
);
1371 ret
= uart_get_rs485_config(uport
, uarg
);
1375 ret
= uart_set_rs485_config(uport
, uarg
);
1378 if (uport
->ops
->ioctl
)
1379 ret
= uport
->ops
->ioctl(uport
, cmd
, arg
);
1383 mutex_unlock(&port
->mutex
);
1388 static void uart_set_ldisc(struct tty_struct
*tty
)
1390 struct uart_state
*state
= tty
->driver_data
;
1391 struct uart_port
*uport
;
1393 mutex_lock(&state
->port
.mutex
);
1394 uport
= uart_port_check(state
);
1395 if (uport
&& uport
->ops
->set_ldisc
)
1396 uport
->ops
->set_ldisc(uport
, &tty
->termios
);
1397 mutex_unlock(&state
->port
.mutex
);
1400 static void uart_set_termios(struct tty_struct
*tty
,
1401 struct ktermios
*old_termios
)
1403 struct uart_state
*state
= tty
->driver_data
;
1404 struct uart_port
*uport
;
1405 unsigned int cflag
= tty
->termios
.c_cflag
;
1406 unsigned int iflag_mask
= IGNBRK
|BRKINT
|IGNPAR
|PARMRK
|INPCK
;
1407 bool sw_changed
= false;
1409 mutex_lock(&state
->port
.mutex
);
1410 uport
= uart_port_check(state
);
1415 * Drivers doing software flow control also need to know
1416 * about changes to these input settings.
1418 if (uport
->flags
& UPF_SOFT_FLOW
) {
1419 iflag_mask
|= IXANY
|IXON
|IXOFF
;
1421 tty
->termios
.c_cc
[VSTART
] != old_termios
->c_cc
[VSTART
] ||
1422 tty
->termios
.c_cc
[VSTOP
] != old_termios
->c_cc
[VSTOP
];
1426 * These are the bits that are used to setup various
1427 * flags in the low level driver. We can ignore the Bfoo
1428 * bits in c_cflag; c_[io]speed will always be set
1429 * appropriately by set_termios() in tty_ioctl.c
1431 if ((cflag
^ old_termios
->c_cflag
) == 0 &&
1432 tty
->termios
.c_ospeed
== old_termios
->c_ospeed
&&
1433 tty
->termios
.c_ispeed
== old_termios
->c_ispeed
&&
1434 ((tty
->termios
.c_iflag
^ old_termios
->c_iflag
) & iflag_mask
) == 0 &&
1439 uart_change_speed(tty
, state
, old_termios
);
1440 /* reload cflag from termios; port driver may have overriden flags */
1441 cflag
= tty
->termios
.c_cflag
;
1443 /* Handle transition to B0 status */
1444 if ((old_termios
->c_cflag
& CBAUD
) && !(cflag
& CBAUD
))
1445 uart_clear_mctrl(uport
, TIOCM_RTS
| TIOCM_DTR
);
1446 /* Handle transition away from B0 status */
1447 else if (!(old_termios
->c_cflag
& CBAUD
) && (cflag
& CBAUD
)) {
1448 unsigned int mask
= TIOCM_DTR
;
1449 if (!(cflag
& CRTSCTS
) || !tty_throttled(tty
))
1451 uart_set_mctrl(uport
, mask
);
1454 mutex_unlock(&state
->port
.mutex
);
1458 * Calls to uart_close() are serialised via the tty_lock in
1459 * drivers/tty/tty_io.c:tty_release()
1460 * drivers/tty/tty_io.c:do_tty_hangup()
1462 static void uart_close(struct tty_struct
*tty
, struct file
*filp
)
1464 struct uart_state
*state
= tty
->driver_data
;
1465 struct tty_port
*port
;
1468 struct uart_driver
*drv
= tty
->driver
->driver_state
;
1470 state
= drv
->state
+ tty
->index
;
1471 port
= &state
->port
;
1472 spin_lock_irq(&port
->lock
);
1474 spin_unlock_irq(&port
->lock
);
1478 port
= &state
->port
;
1479 pr_debug("uart_close(%d) called\n", tty
->index
);
1481 tty_port_close(tty
->port
, tty
, filp
);
1484 static void uart_tty_port_shutdown(struct tty_port
*port
)
1486 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1487 struct uart_port
*uport
= uart_port_check(state
);
1490 * At this point, we stop accepting input. To do this, we
1491 * disable the receive line status interrupts.
1493 if (WARN(!uport
, "detached port still initialized!\n"))
1496 spin_lock_irq(&uport
->lock
);
1497 uport
->ops
->stop_rx(uport
);
1498 spin_unlock_irq(&uport
->lock
);
1500 uart_port_shutdown(port
);
1503 * It's possible for shutdown to be called after suspend if we get
1504 * a DCD drop (hangup) at just the right time. Clear suspended bit so
1505 * we don't try to resume a port that has been shutdown.
1507 tty_port_set_suspended(port
, 0);
1509 uart_change_pm(state
, UART_PM_STATE_OFF
);
1513 static void uart_wait_until_sent(struct tty_struct
*tty
, int timeout
)
1515 struct uart_state
*state
= tty
->driver_data
;
1516 struct uart_port
*port
;
1517 unsigned long char_time
, expire
;
1519 port
= uart_port_ref(state
);
1523 if (port
->type
== PORT_UNKNOWN
|| port
->fifosize
== 0) {
1524 uart_port_deref(port
);
1529 * Set the check interval to be 1/5 of the estimated time to
1530 * send a single character, and make it at least 1. The check
1531 * interval should also be less than the timeout.
1533 * Note: we have to use pretty tight timings here to satisfy
1536 char_time
= (port
->timeout
- HZ
/50) / port
->fifosize
;
1537 char_time
= char_time
/ 5;
1540 if (timeout
&& timeout
< char_time
)
1541 char_time
= timeout
;
1544 * If the transmitter hasn't cleared in twice the approximate
1545 * amount of time to send the entire FIFO, it probably won't
1546 * ever clear. This assumes the UART isn't doing flow
1547 * control, which is currently the case. Hence, if it ever
1548 * takes longer than port->timeout, this is probably due to a
1549 * UART bug of some kind. So, we clamp the timeout parameter at
1552 if (timeout
== 0 || timeout
> 2 * port
->timeout
)
1553 timeout
= 2 * port
->timeout
;
1555 expire
= jiffies
+ timeout
;
1557 pr_debug("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n",
1558 port
->line
, jiffies
, expire
);
1561 * Check whether the transmitter is empty every 'char_time'.
1562 * 'timeout' / 'expire' give us the maximum amount of time
1565 while (!port
->ops
->tx_empty(port
)) {
1566 msleep_interruptible(jiffies_to_msecs(char_time
));
1567 if (signal_pending(current
))
1569 if (time_after(jiffies
, expire
))
1572 uart_port_deref(port
);
1576 * Calls to uart_hangup() are serialised by the tty_lock in
1577 * drivers/tty/tty_io.c:do_tty_hangup()
1578 * This runs from a workqueue and can sleep for a _short_ time only.
1580 static void uart_hangup(struct tty_struct
*tty
)
1582 struct uart_state
*state
= tty
->driver_data
;
1583 struct tty_port
*port
= &state
->port
;
1584 struct uart_port
*uport
;
1585 unsigned long flags
;
1587 pr_debug("uart_hangup(%d)\n", tty
->index
);
1589 mutex_lock(&port
->mutex
);
1590 uport
= uart_port_check(state
);
1591 WARN(!uport
, "hangup of detached port!\n");
1593 if (tty_port_active(port
)) {
1594 uart_flush_buffer(tty
);
1595 uart_shutdown(tty
, state
);
1596 spin_lock_irqsave(&port
->lock
, flags
);
1598 spin_unlock_irqrestore(&port
->lock
, flags
);
1599 tty_port_set_active(port
, 0);
1600 tty_port_tty_set(port
, NULL
);
1601 if (uport
&& !uart_console(uport
))
1602 uart_change_pm(state
, UART_PM_STATE_OFF
);
1603 wake_up_interruptible(&port
->open_wait
);
1604 wake_up_interruptible(&port
->delta_msr_wait
);
1606 mutex_unlock(&port
->mutex
);
1609 /* uport == NULL if uart_port has already been removed */
1610 static void uart_port_shutdown(struct tty_port
*port
)
1612 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1613 struct uart_port
*uport
= uart_port_check(state
);
1616 * clear delta_msr_wait queue to avoid mem leaks: we may free
1617 * the irq here so the queue might never be woken up. Note
1618 * that we won't end up waiting on delta_msr_wait again since
1619 * any outstanding file descriptors should be pointing at
1620 * hung_up_tty_fops now.
1622 wake_up_interruptible(&port
->delta_msr_wait
);
1625 * Free the IRQ and disable the port.
1628 uport
->ops
->shutdown(uport
);
1631 * Ensure that the IRQ handler isn't running on another CPU.
1634 synchronize_irq(uport
->irq
);
1637 static int uart_carrier_raised(struct tty_port
*port
)
1639 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1640 struct uart_port
*uport
;
1643 uport
= uart_port_ref(state
);
1645 * Should never observe uport == NULL since checks for hangup should
1646 * abort the tty_port_block_til_ready() loop before checking for carrier
1647 * raised -- but report carrier raised if it does anyway so open will
1648 * continue and not sleep
1650 if (WARN_ON(!uport
))
1652 spin_lock_irq(&uport
->lock
);
1653 uart_enable_ms(uport
);
1654 mctrl
= uport
->ops
->get_mctrl(uport
);
1655 spin_unlock_irq(&uport
->lock
);
1656 uart_port_deref(uport
);
1657 if (mctrl
& TIOCM_CAR
)
1662 static void uart_dtr_rts(struct tty_port
*port
, int onoff
)
1664 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1665 struct uart_port
*uport
;
1667 uport
= uart_port_ref(state
);
1672 uart_set_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
1674 uart_clear_mctrl(uport
, TIOCM_DTR
| TIOCM_RTS
);
1676 uart_port_deref(uport
);
1680 * Calls to uart_open are serialised by the tty_lock in
1681 * drivers/tty/tty_io.c:tty_open()
1682 * Note that if this fails, then uart_close() _will_ be called.
1684 * In time, we want to scrap the "opening nonpresent ports"
1685 * behaviour and implement an alternative way for setserial
1686 * to set base addresses/ports/types. This will allow us to
1687 * get rid of a certain amount of extra tests.
1689 static int uart_open(struct tty_struct
*tty
, struct file
*filp
)
1691 struct uart_driver
*drv
= tty
->driver
->driver_state
;
1692 int retval
, line
= tty
->index
;
1693 struct uart_state
*state
= drv
->state
+ line
;
1695 tty
->driver_data
= state
;
1697 retval
= tty_port_open(&state
->port
, tty
, filp
);
1704 static int uart_port_activate(struct tty_port
*port
, struct tty_struct
*tty
)
1706 struct uart_state
*state
= container_of(port
, struct uart_state
, port
);
1707 struct uart_port
*uport
;
1709 uport
= uart_port_check(state
);
1710 if (!uport
|| uport
->flags
& UPF_DEAD
)
1713 port
->low_latency
= (uport
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
1716 * Start up the serial port.
1718 return uart_startup(tty
, state
, 0);
1721 static const char *uart_type(struct uart_port
*port
)
1723 const char *str
= NULL
;
1725 if (port
->ops
->type
)
1726 str
= port
->ops
->type(port
);
1734 #ifdef CONFIG_PROC_FS
1736 static void uart_line_info(struct seq_file
*m
, struct uart_driver
*drv
, int i
)
1738 struct uart_state
*state
= drv
->state
+ i
;
1739 struct tty_port
*port
= &state
->port
;
1740 enum uart_pm_state pm_state
;
1741 struct uart_port
*uport
;
1743 unsigned int status
;
1746 mutex_lock(&port
->mutex
);
1747 uport
= uart_port_check(state
);
1751 mmio
= uport
->iotype
>= UPIO_MEM
;
1752 seq_printf(m
, "%d: uart:%s %s%08llX irq:%d",
1753 uport
->line
, uart_type(uport
),
1754 mmio
? "mmio:0x" : "port:",
1755 mmio
? (unsigned long long)uport
->mapbase
1756 : (unsigned long long)uport
->iobase
,
1759 if (uport
->type
== PORT_UNKNOWN
) {
1764 if (capable(CAP_SYS_ADMIN
)) {
1765 pm_state
= state
->pm_state
;
1766 if (pm_state
!= UART_PM_STATE_ON
)
1767 uart_change_pm(state
, UART_PM_STATE_ON
);
1768 spin_lock_irq(&uport
->lock
);
1769 status
= uport
->ops
->get_mctrl(uport
);
1770 spin_unlock_irq(&uport
->lock
);
1771 if (pm_state
!= UART_PM_STATE_ON
)
1772 uart_change_pm(state
, pm_state
);
1774 seq_printf(m
, " tx:%d rx:%d",
1775 uport
->icount
.tx
, uport
->icount
.rx
);
1776 if (uport
->icount
.frame
)
1777 seq_printf(m
, " fe:%d", uport
->icount
.frame
);
1778 if (uport
->icount
.parity
)
1779 seq_printf(m
, " pe:%d", uport
->icount
.parity
);
1780 if (uport
->icount
.brk
)
1781 seq_printf(m
, " brk:%d", uport
->icount
.brk
);
1782 if (uport
->icount
.overrun
)
1783 seq_printf(m
, " oe:%d", uport
->icount
.overrun
);
1785 #define INFOBIT(bit, str) \
1786 if (uport->mctrl & (bit)) \
1787 strncat(stat_buf, (str), sizeof(stat_buf) - \
1788 strlen(stat_buf) - 2)
1789 #define STATBIT(bit, str) \
1790 if (status & (bit)) \
1791 strncat(stat_buf, (str), sizeof(stat_buf) - \
1792 strlen(stat_buf) - 2)
1796 INFOBIT(TIOCM_RTS
, "|RTS");
1797 STATBIT(TIOCM_CTS
, "|CTS");
1798 INFOBIT(TIOCM_DTR
, "|DTR");
1799 STATBIT(TIOCM_DSR
, "|DSR");
1800 STATBIT(TIOCM_CAR
, "|CD");
1801 STATBIT(TIOCM_RNG
, "|RI");
1805 seq_puts(m
, stat_buf
);
1811 mutex_unlock(&port
->mutex
);
1814 static int uart_proc_show(struct seq_file
*m
, void *v
)
1816 struct tty_driver
*ttydrv
= m
->private;
1817 struct uart_driver
*drv
= ttydrv
->driver_state
;
1820 seq_printf(m
, "serinfo:1.0 driver%s%s revision:%s\n", "", "", "");
1821 for (i
= 0; i
< drv
->nr
; i
++)
1822 uart_line_info(m
, drv
, i
);
1826 static int uart_proc_open(struct inode
*inode
, struct file
*file
)
1828 return single_open(file
, uart_proc_show
, PDE_DATA(inode
));
1831 static const struct file_operations uart_proc_fops
= {
1832 .owner
= THIS_MODULE
,
1833 .open
= uart_proc_open
,
1835 .llseek
= seq_lseek
,
1836 .release
= single_release
,
1840 #if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(CONFIG_CONSOLE_POLL)
1842 * uart_console_write - write a console message to a serial port
1843 * @port: the port to write the message
1844 * @s: array of characters
1845 * @count: number of characters in string to write
1846 * @putchar: function to write character to port
1848 void uart_console_write(struct uart_port
*port
, const char *s
,
1850 void (*putchar
)(struct uart_port
*, int))
1854 for (i
= 0; i
< count
; i
++, s
++) {
1856 putchar(port
, '\r');
1860 EXPORT_SYMBOL_GPL(uart_console_write
);
1863 * Check whether an invalid uart number has been specified, and
1864 * if so, search for the first available port that does have
1867 struct uart_port
* __init
1868 uart_get_console(struct uart_port
*ports
, int nr
, struct console
*co
)
1870 int idx
= co
->index
;
1872 if (idx
< 0 || idx
>= nr
|| (ports
[idx
].iobase
== 0 &&
1873 ports
[idx
].membase
== NULL
))
1874 for (idx
= 0; idx
< nr
; idx
++)
1875 if (ports
[idx
].iobase
!= 0 ||
1876 ports
[idx
].membase
!= NULL
)
1885 * uart_parse_earlycon - Parse earlycon options
1886 * @p: ptr to 2nd field (ie., just beyond '<name>,')
1887 * @iotype: ptr for decoded iotype (out)
1888 * @addr: ptr for decoded mapbase/iobase (out)
1889 * @options: ptr for <options> field; NULL if not present (out)
1891 * Decodes earlycon kernel command line parameters of the form
1892 * earlycon=<name>,io|mmio|mmio16|mmio32|mmio32be|mmio32native,<addr>,<options>
1893 * console=<name>,io|mmio|mmio16|mmio32|mmio32be|mmio32native,<addr>,<options>
1896 * earlycon=<name>,0x<addr>,<options>
1897 * console=<name>,0x<addr>,<options>
1898 * is also accepted; the returned @iotype will be UPIO_MEM.
1900 * Returns 0 on success or -EINVAL on failure
1902 int uart_parse_earlycon(char *p
, unsigned char *iotype
, resource_size_t
*addr
,
1905 if (strncmp(p
, "mmio,", 5) == 0) {
1908 } else if (strncmp(p
, "mmio16,", 7) == 0) {
1909 *iotype
= UPIO_MEM16
;
1911 } else if (strncmp(p
, "mmio32,", 7) == 0) {
1912 *iotype
= UPIO_MEM32
;
1914 } else if (strncmp(p
, "mmio32be,", 9) == 0) {
1915 *iotype
= UPIO_MEM32BE
;
1917 } else if (strncmp(p
, "mmio32native,", 13) == 0) {
1918 *iotype
= IS_ENABLED(CONFIG_CPU_BIG_ENDIAN
) ?
1919 UPIO_MEM32BE
: UPIO_MEM32
;
1921 } else if (strncmp(p
, "io,", 3) == 0) {
1922 *iotype
= UPIO_PORT
;
1924 } else if (strncmp(p
, "0x", 2) == 0) {
1931 * Before you replace it with kstrtoull(), think about options separator
1932 * (',') it will not tolerate
1934 *addr
= simple_strtoull(p
, NULL
, 0);
1942 EXPORT_SYMBOL_GPL(uart_parse_earlycon
);
1945 * uart_parse_options - Parse serial port baud/parity/bits/flow control.
1946 * @options: pointer to option string
1947 * @baud: pointer to an 'int' variable for the baud rate.
1948 * @parity: pointer to an 'int' variable for the parity.
1949 * @bits: pointer to an 'int' variable for the number of data bits.
1950 * @flow: pointer to an 'int' variable for the flow control character.
1952 * uart_parse_options decodes a string containing the serial console
1953 * options. The format of the string is <baud><parity><bits><flow>,
1957 uart_parse_options(char *options
, int *baud
, int *parity
, int *bits
, int *flow
)
1961 *baud
= simple_strtoul(s
, NULL
, 10);
1962 while (*s
>= '0' && *s
<= '9')
1971 EXPORT_SYMBOL_GPL(uart_parse_options
);
1974 * uart_set_options - setup the serial console parameters
1975 * @port: pointer to the serial ports uart_port structure
1976 * @co: console pointer
1978 * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even)
1979 * @bits: number of data bits
1980 * @flow: flow control character - 'r' (rts)
1983 uart_set_options(struct uart_port
*port
, struct console
*co
,
1984 int baud
, int parity
, int bits
, int flow
)
1986 struct ktermios termios
;
1987 static struct ktermios dummy
;
1990 * Ensure that the serial console lock is initialised
1992 * If this port is a console, then the spinlock is already
1995 if (!(uart_console(port
) && (port
->cons
->flags
& CON_ENABLED
))) {
1996 spin_lock_init(&port
->lock
);
1997 lockdep_set_class(&port
->lock
, &port_lock_key
);
2000 memset(&termios
, 0, sizeof(struct ktermios
));
2002 termios
.c_cflag
|= CREAD
| HUPCL
| CLOCAL
;
2003 tty_termios_encode_baud_rate(&termios
, baud
, baud
);
2006 termios
.c_cflag
|= CS7
;
2008 termios
.c_cflag
|= CS8
;
2012 termios
.c_cflag
|= PARODD
;
2015 termios
.c_cflag
|= PARENB
;
2020 termios
.c_cflag
|= CRTSCTS
;
2023 * some uarts on other side don't support no flow control.
2024 * So we set * DTR in host uart to make them happy
2026 port
->mctrl
|= TIOCM_DTR
;
2028 port
->ops
->set_termios(port
, &termios
, &dummy
);
2030 * Allow the setting of the UART parameters with a NULL console
2034 co
->cflag
= termios
.c_cflag
;
2038 EXPORT_SYMBOL_GPL(uart_set_options
);
2039 #endif /* CONFIG_SERIAL_CORE_CONSOLE */
2042 * uart_change_pm - set power state of the port
2044 * @state: port descriptor
2045 * @pm_state: new state
2047 * Locking: port->mutex has to be held
2049 static void uart_change_pm(struct uart_state
*state
,
2050 enum uart_pm_state pm_state
)
2052 struct uart_port
*port
= uart_port_check(state
);
2054 if (state
->pm_state
!= pm_state
) {
2055 if (port
&& port
->ops
->pm
)
2056 port
->ops
->pm(port
, pm_state
, state
->pm_state
);
2057 state
->pm_state
= pm_state
;
2062 struct uart_port
*port
;
2063 struct uart_driver
*driver
;
2066 static int serial_match_port(struct device
*dev
, void *data
)
2068 struct uart_match
*match
= data
;
2069 struct tty_driver
*tty_drv
= match
->driver
->tty_driver
;
2070 dev_t devt
= MKDEV(tty_drv
->major
, tty_drv
->minor_start
) +
2073 return dev
->devt
== devt
; /* Actually, only one tty per port */
2076 int uart_suspend_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2078 struct uart_state
*state
= drv
->state
+ uport
->line
;
2079 struct tty_port
*port
= &state
->port
;
2080 struct device
*tty_dev
;
2081 struct uart_match match
= {uport
, drv
};
2083 mutex_lock(&port
->mutex
);
2085 tty_dev
= device_find_child(uport
->dev
, &match
, serial_match_port
);
2086 if (device_may_wakeup(tty_dev
)) {
2087 if (!enable_irq_wake(uport
->irq
))
2088 uport
->irq_wake
= 1;
2089 put_device(tty_dev
);
2090 mutex_unlock(&port
->mutex
);
2093 put_device(tty_dev
);
2095 /* Nothing to do if the console is not suspending */
2096 if (!console_suspend_enabled
&& uart_console(uport
))
2099 uport
->suspended
= 1;
2101 if (tty_port_initialized(port
)) {
2102 const struct uart_ops
*ops
= uport
->ops
;
2105 tty_port_set_suspended(port
, 1);
2106 tty_port_set_initialized(port
, 0);
2108 spin_lock_irq(&uport
->lock
);
2109 ops
->stop_tx(uport
);
2110 ops
->set_mctrl(uport
, 0);
2111 ops
->stop_rx(uport
);
2112 spin_unlock_irq(&uport
->lock
);
2115 * Wait for the transmitter to empty.
2117 for (tries
= 3; !ops
->tx_empty(uport
) && tries
; tries
--)
2120 dev_err(uport
->dev
, "%s%d: Unable to drain transmitter\n",
2122 drv
->tty_driver
->name_base
+ uport
->line
);
2124 ops
->shutdown(uport
);
2128 * Disable the console device before suspending.
2130 if (uart_console(uport
))
2131 console_stop(uport
->cons
);
2133 uart_change_pm(state
, UART_PM_STATE_OFF
);
2135 mutex_unlock(&port
->mutex
);
2140 int uart_resume_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2142 struct uart_state
*state
= drv
->state
+ uport
->line
;
2143 struct tty_port
*port
= &state
->port
;
2144 struct device
*tty_dev
;
2145 struct uart_match match
= {uport
, drv
};
2146 struct ktermios termios
;
2148 mutex_lock(&port
->mutex
);
2150 tty_dev
= device_find_child(uport
->dev
, &match
, serial_match_port
);
2151 if (!uport
->suspended
&& device_may_wakeup(tty_dev
)) {
2152 if (uport
->irq_wake
) {
2153 disable_irq_wake(uport
->irq
);
2154 uport
->irq_wake
= 0;
2156 put_device(tty_dev
);
2157 mutex_unlock(&port
->mutex
);
2160 put_device(tty_dev
);
2161 uport
->suspended
= 0;
2164 * Re-enable the console device after suspending.
2166 if (uart_console(uport
)) {
2168 * First try to use the console cflag setting.
2170 memset(&termios
, 0, sizeof(struct ktermios
));
2171 termios
.c_cflag
= uport
->cons
->cflag
;
2174 * If that's unset, use the tty termios setting.
2176 if (port
->tty
&& termios
.c_cflag
== 0)
2177 termios
= port
->tty
->termios
;
2179 if (console_suspend_enabled
)
2180 uart_change_pm(state
, UART_PM_STATE_ON
);
2181 uport
->ops
->set_termios(uport
, &termios
, NULL
);
2182 if (console_suspend_enabled
)
2183 console_start(uport
->cons
);
2186 if (tty_port_suspended(port
)) {
2187 const struct uart_ops
*ops
= uport
->ops
;
2190 uart_change_pm(state
, UART_PM_STATE_ON
);
2191 spin_lock_irq(&uport
->lock
);
2192 ops
->set_mctrl(uport
, 0);
2193 spin_unlock_irq(&uport
->lock
);
2194 if (console_suspend_enabled
|| !uart_console(uport
)) {
2195 /* Protected by port mutex for now */
2196 struct tty_struct
*tty
= port
->tty
;
2197 ret
= ops
->startup(uport
);
2200 uart_change_speed(tty
, state
, NULL
);
2201 spin_lock_irq(&uport
->lock
);
2202 ops
->set_mctrl(uport
, uport
->mctrl
);
2203 ops
->start_tx(uport
);
2204 spin_unlock_irq(&uport
->lock
);
2205 tty_port_set_initialized(port
, 1);
2208 * Failed to resume - maybe hardware went away?
2209 * Clear the "initialized" flag so we won't try
2210 * to call the low level drivers shutdown method.
2212 uart_shutdown(tty
, state
);
2216 tty_port_set_suspended(port
, 0);
2219 mutex_unlock(&port
->mutex
);
2225 uart_report_port(struct uart_driver
*drv
, struct uart_port
*port
)
2229 switch (port
->iotype
) {
2231 snprintf(address
, sizeof(address
), "I/O 0x%lx", port
->iobase
);
2234 snprintf(address
, sizeof(address
),
2235 "I/O 0x%lx offset 0x%x", port
->iobase
, port
->hub6
);
2243 snprintf(address
, sizeof(address
),
2244 "MMIO 0x%llx", (unsigned long long)port
->mapbase
);
2247 strlcpy(address
, "*unknown*", sizeof(address
));
2251 printk(KERN_INFO
"%s%s%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
2252 port
->dev
? dev_name(port
->dev
) : "",
2253 port
->dev
? ": " : "",
2255 drv
->tty_driver
->name_base
+ port
->line
,
2256 address
, port
->irq
, port
->uartclk
/ 16, uart_type(port
));
2260 uart_configure_port(struct uart_driver
*drv
, struct uart_state
*state
,
2261 struct uart_port
*port
)
2266 * If there isn't a port here, don't do anything further.
2268 if (!port
->iobase
&& !port
->mapbase
&& !port
->membase
)
2272 * Now do the auto configuration stuff. Note that config_port
2273 * is expected to claim the resources and map the port for us.
2276 if (port
->flags
& UPF_AUTO_IRQ
)
2277 flags
|= UART_CONFIG_IRQ
;
2278 if (port
->flags
& UPF_BOOT_AUTOCONF
) {
2279 if (!(port
->flags
& UPF_FIXED_TYPE
)) {
2280 port
->type
= PORT_UNKNOWN
;
2281 flags
|= UART_CONFIG_TYPE
;
2283 port
->ops
->config_port(port
, flags
);
2286 if (port
->type
!= PORT_UNKNOWN
) {
2287 unsigned long flags
;
2289 uart_report_port(drv
, port
);
2291 /* Power up port for set_mctrl() */
2292 uart_change_pm(state
, UART_PM_STATE_ON
);
2295 * Ensure that the modem control lines are de-activated.
2296 * keep the DTR setting that is set in uart_set_options()
2297 * We probably don't need a spinlock around this, but
2299 spin_lock_irqsave(&port
->lock
, flags
);
2300 port
->ops
->set_mctrl(port
, port
->mctrl
& TIOCM_DTR
);
2301 spin_unlock_irqrestore(&port
->lock
, flags
);
2304 * If this driver supports console, and it hasn't been
2305 * successfully registered yet, try to re-register it.
2306 * It may be that the port was not available.
2308 if (port
->cons
&& !(port
->cons
->flags
& CON_ENABLED
))
2309 register_console(port
->cons
);
2312 * Power down all ports by default, except the
2313 * console if we have one.
2315 if (!uart_console(port
))
2316 uart_change_pm(state
, UART_PM_STATE_OFF
);
2320 #ifdef CONFIG_CONSOLE_POLL
2322 static int uart_poll_init(struct tty_driver
*driver
, int line
, char *options
)
2324 struct uart_driver
*drv
= driver
->driver_state
;
2325 struct uart_state
*state
= drv
->state
+ line
;
2326 struct tty_port
*tport
;
2327 struct uart_port
*port
;
2337 tport
= &state
->port
;
2338 mutex_lock(&tport
->mutex
);
2340 port
= uart_port_check(state
);
2341 if (!port
|| !(port
->ops
->poll_get_char
&& port
->ops
->poll_put_char
)) {
2346 if (port
->ops
->poll_init
) {
2348 * We don't set initialized as we only initialized the hw,
2349 * e.g. state->xmit is still uninitialized.
2351 if (!tty_port_initialized(tport
))
2352 ret
= port
->ops
->poll_init(port
);
2355 if (!ret
&& options
) {
2356 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
2357 ret
= uart_set_options(port
, NULL
, baud
, parity
, bits
, flow
);
2360 mutex_unlock(&tport
->mutex
);
2364 static int uart_poll_get_char(struct tty_driver
*driver
, int line
)
2366 struct uart_driver
*drv
= driver
->driver_state
;
2367 struct uart_state
*state
= drv
->state
+ line
;
2368 struct uart_port
*port
;
2372 port
= uart_port_ref(state
);
2374 ret
= port
->ops
->poll_get_char(port
);
2375 uart_port_deref(port
);
2381 static void uart_poll_put_char(struct tty_driver
*driver
, int line
, char ch
)
2383 struct uart_driver
*drv
= driver
->driver_state
;
2384 struct uart_state
*state
= drv
->state
+ line
;
2385 struct uart_port
*port
;
2390 port
= uart_port_ref(state
);
2395 port
->ops
->poll_put_char(port
, '\r');
2396 port
->ops
->poll_put_char(port
, ch
);
2397 uart_port_deref(port
);
2401 static const struct tty_operations uart_ops
= {
2403 .close
= uart_close
,
2404 .write
= uart_write
,
2405 .put_char
= uart_put_char
,
2406 .flush_chars
= uart_flush_chars
,
2407 .write_room
= uart_write_room
,
2408 .chars_in_buffer
= uart_chars_in_buffer
,
2409 .flush_buffer
= uart_flush_buffer
,
2410 .ioctl
= uart_ioctl
,
2411 .throttle
= uart_throttle
,
2412 .unthrottle
= uart_unthrottle
,
2413 .send_xchar
= uart_send_xchar
,
2414 .set_termios
= uart_set_termios
,
2415 .set_ldisc
= uart_set_ldisc
,
2417 .start
= uart_start
,
2418 .hangup
= uart_hangup
,
2419 .break_ctl
= uart_break_ctl
,
2420 .wait_until_sent
= uart_wait_until_sent
,
2421 #ifdef CONFIG_PROC_FS
2422 .proc_fops
= &uart_proc_fops
,
2424 .tiocmget
= uart_tiocmget
,
2425 .tiocmset
= uart_tiocmset
,
2426 .get_icount
= uart_get_icount
,
2427 #ifdef CONFIG_CONSOLE_POLL
2428 .poll_init
= uart_poll_init
,
2429 .poll_get_char
= uart_poll_get_char
,
2430 .poll_put_char
= uart_poll_put_char
,
2434 static const struct tty_port_operations uart_port_ops
= {
2435 .carrier_raised
= uart_carrier_raised
,
2436 .dtr_rts
= uart_dtr_rts
,
2437 .activate
= uart_port_activate
,
2438 .shutdown
= uart_tty_port_shutdown
,
2442 * uart_register_driver - register a driver with the uart core layer
2443 * @drv: low level driver structure
2445 * Register a uart driver with the core driver. We in turn register
2446 * with the tty layer, and initialise the core driver per-port state.
2448 * We have a proc file in /proc/tty/driver which is named after the
2451 * drv->port should be NULL, and the per-port structures should be
2452 * registered using uart_add_one_port after this call has succeeded.
2454 int uart_register_driver(struct uart_driver
*drv
)
2456 struct tty_driver
*normal
;
2462 * Maybe we should be using a slab cache for this, especially if
2463 * we have a large number of ports to handle.
2465 drv
->state
= kzalloc(sizeof(struct uart_state
) * drv
->nr
, GFP_KERNEL
);
2469 normal
= alloc_tty_driver(drv
->nr
);
2473 drv
->tty_driver
= normal
;
2475 normal
->driver_name
= drv
->driver_name
;
2476 normal
->name
= drv
->dev_name
;
2477 normal
->major
= drv
->major
;
2478 normal
->minor_start
= drv
->minor
;
2479 normal
->type
= TTY_DRIVER_TYPE_SERIAL
;
2480 normal
->subtype
= SERIAL_TYPE_NORMAL
;
2481 normal
->init_termios
= tty_std_termios
;
2482 normal
->init_termios
.c_cflag
= B9600
| CS8
| CREAD
| HUPCL
| CLOCAL
;
2483 normal
->init_termios
.c_ispeed
= normal
->init_termios
.c_ospeed
= 9600;
2484 normal
->flags
= TTY_DRIVER_REAL_RAW
| TTY_DRIVER_DYNAMIC_DEV
;
2485 normal
->driver_state
= drv
;
2486 tty_set_operations(normal
, &uart_ops
);
2489 * Initialise the UART state(s).
2491 for (i
= 0; i
< drv
->nr
; i
++) {
2492 struct uart_state
*state
= drv
->state
+ i
;
2493 struct tty_port
*port
= &state
->port
;
2495 tty_port_init(port
);
2496 port
->ops
= &uart_port_ops
;
2499 retval
= tty_register_driver(normal
);
2503 for (i
= 0; i
< drv
->nr
; i
++)
2504 tty_port_destroy(&drv
->state
[i
].port
);
2505 put_tty_driver(normal
);
2513 * uart_unregister_driver - remove a driver from the uart core layer
2514 * @drv: low level driver structure
2516 * Remove all references to a driver from the core driver. The low
2517 * level driver must have removed all its ports via the
2518 * uart_remove_one_port() if it registered them with uart_add_one_port().
2519 * (ie, drv->port == NULL)
2521 void uart_unregister_driver(struct uart_driver
*drv
)
2523 struct tty_driver
*p
= drv
->tty_driver
;
2526 tty_unregister_driver(p
);
2528 for (i
= 0; i
< drv
->nr
; i
++)
2529 tty_port_destroy(&drv
->state
[i
].port
);
2532 drv
->tty_driver
= NULL
;
2535 struct tty_driver
*uart_console_device(struct console
*co
, int *index
)
2537 struct uart_driver
*p
= co
->data
;
2539 return p
->tty_driver
;
2542 static ssize_t
uart_get_attr_uartclk(struct device
*dev
,
2543 struct device_attribute
*attr
, char *buf
)
2545 struct serial_struct tmp
;
2546 struct tty_port
*port
= dev_get_drvdata(dev
);
2548 uart_get_info(port
, &tmp
);
2549 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.baud_base
* 16);
2552 static ssize_t
uart_get_attr_type(struct device
*dev
,
2553 struct device_attribute
*attr
, char *buf
)
2555 struct serial_struct tmp
;
2556 struct tty_port
*port
= dev_get_drvdata(dev
);
2558 uart_get_info(port
, &tmp
);
2559 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.type
);
2561 static ssize_t
uart_get_attr_line(struct device
*dev
,
2562 struct device_attribute
*attr
, char *buf
)
2564 struct serial_struct tmp
;
2565 struct tty_port
*port
= dev_get_drvdata(dev
);
2567 uart_get_info(port
, &tmp
);
2568 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.line
);
2571 static ssize_t
uart_get_attr_port(struct device
*dev
,
2572 struct device_attribute
*attr
, char *buf
)
2574 struct serial_struct tmp
;
2575 struct tty_port
*port
= dev_get_drvdata(dev
);
2576 unsigned long ioaddr
;
2578 uart_get_info(port
, &tmp
);
2580 if (HIGH_BITS_OFFSET
)
2581 ioaddr
|= (unsigned long)tmp
.port_high
<< HIGH_BITS_OFFSET
;
2582 return snprintf(buf
, PAGE_SIZE
, "0x%lX\n", ioaddr
);
2585 static ssize_t
uart_get_attr_irq(struct device
*dev
,
2586 struct device_attribute
*attr
, char *buf
)
2588 struct serial_struct tmp
;
2589 struct tty_port
*port
= dev_get_drvdata(dev
);
2591 uart_get_info(port
, &tmp
);
2592 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.irq
);
2595 static ssize_t
uart_get_attr_flags(struct device
*dev
,
2596 struct device_attribute
*attr
, char *buf
)
2598 struct serial_struct tmp
;
2599 struct tty_port
*port
= dev_get_drvdata(dev
);
2601 uart_get_info(port
, &tmp
);
2602 return snprintf(buf
, PAGE_SIZE
, "0x%X\n", tmp
.flags
);
2605 static ssize_t
uart_get_attr_xmit_fifo_size(struct device
*dev
,
2606 struct device_attribute
*attr
, char *buf
)
2608 struct serial_struct tmp
;
2609 struct tty_port
*port
= dev_get_drvdata(dev
);
2611 uart_get_info(port
, &tmp
);
2612 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.xmit_fifo_size
);
2616 static ssize_t
uart_get_attr_close_delay(struct device
*dev
,
2617 struct device_attribute
*attr
, char *buf
)
2619 struct serial_struct tmp
;
2620 struct tty_port
*port
= dev_get_drvdata(dev
);
2622 uart_get_info(port
, &tmp
);
2623 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.close_delay
);
2627 static ssize_t
uart_get_attr_closing_wait(struct device
*dev
,
2628 struct device_attribute
*attr
, char *buf
)
2630 struct serial_struct tmp
;
2631 struct tty_port
*port
= dev_get_drvdata(dev
);
2633 uart_get_info(port
, &tmp
);
2634 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.closing_wait
);
2637 static ssize_t
uart_get_attr_custom_divisor(struct device
*dev
,
2638 struct device_attribute
*attr
, char *buf
)
2640 struct serial_struct tmp
;
2641 struct tty_port
*port
= dev_get_drvdata(dev
);
2643 uart_get_info(port
, &tmp
);
2644 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.custom_divisor
);
2647 static ssize_t
uart_get_attr_io_type(struct device
*dev
,
2648 struct device_attribute
*attr
, char *buf
)
2650 struct serial_struct tmp
;
2651 struct tty_port
*port
= dev_get_drvdata(dev
);
2653 uart_get_info(port
, &tmp
);
2654 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.io_type
);
2657 static ssize_t
uart_get_attr_iomem_base(struct device
*dev
,
2658 struct device_attribute
*attr
, char *buf
)
2660 struct serial_struct tmp
;
2661 struct tty_port
*port
= dev_get_drvdata(dev
);
2663 uart_get_info(port
, &tmp
);
2664 return snprintf(buf
, PAGE_SIZE
, "0x%lX\n", (unsigned long)tmp
.iomem_base
);
2667 static ssize_t
uart_get_attr_iomem_reg_shift(struct device
*dev
,
2668 struct device_attribute
*attr
, char *buf
)
2670 struct serial_struct tmp
;
2671 struct tty_port
*port
= dev_get_drvdata(dev
);
2673 uart_get_info(port
, &tmp
);
2674 return snprintf(buf
, PAGE_SIZE
, "%d\n", tmp
.iomem_reg_shift
);
2677 static DEVICE_ATTR(type
, S_IRUSR
| S_IRGRP
, uart_get_attr_type
, NULL
);
2678 static DEVICE_ATTR(line
, S_IRUSR
| S_IRGRP
, uart_get_attr_line
, NULL
);
2679 static DEVICE_ATTR(port
, S_IRUSR
| S_IRGRP
, uart_get_attr_port
, NULL
);
2680 static DEVICE_ATTR(irq
, S_IRUSR
| S_IRGRP
, uart_get_attr_irq
, NULL
);
2681 static DEVICE_ATTR(flags
, S_IRUSR
| S_IRGRP
, uart_get_attr_flags
, NULL
);
2682 static DEVICE_ATTR(xmit_fifo_size
, S_IRUSR
| S_IRGRP
, uart_get_attr_xmit_fifo_size
, NULL
);
2683 static DEVICE_ATTR(uartclk
, S_IRUSR
| S_IRGRP
, uart_get_attr_uartclk
, NULL
);
2684 static DEVICE_ATTR(close_delay
, S_IRUSR
| S_IRGRP
, uart_get_attr_close_delay
, NULL
);
2685 static DEVICE_ATTR(closing_wait
, S_IRUSR
| S_IRGRP
, uart_get_attr_closing_wait
, NULL
);
2686 static DEVICE_ATTR(custom_divisor
, S_IRUSR
| S_IRGRP
, uart_get_attr_custom_divisor
, NULL
);
2687 static DEVICE_ATTR(io_type
, S_IRUSR
| S_IRGRP
, uart_get_attr_io_type
, NULL
);
2688 static DEVICE_ATTR(iomem_base
, S_IRUSR
| S_IRGRP
, uart_get_attr_iomem_base
, NULL
);
2689 static DEVICE_ATTR(iomem_reg_shift
, S_IRUSR
| S_IRGRP
, uart_get_attr_iomem_reg_shift
, NULL
);
2691 static struct attribute
*tty_dev_attrs
[] = {
2692 &dev_attr_type
.attr
,
2693 &dev_attr_line
.attr
,
2694 &dev_attr_port
.attr
,
2696 &dev_attr_flags
.attr
,
2697 &dev_attr_xmit_fifo_size
.attr
,
2698 &dev_attr_uartclk
.attr
,
2699 &dev_attr_close_delay
.attr
,
2700 &dev_attr_closing_wait
.attr
,
2701 &dev_attr_custom_divisor
.attr
,
2702 &dev_attr_io_type
.attr
,
2703 &dev_attr_iomem_base
.attr
,
2704 &dev_attr_iomem_reg_shift
.attr
,
2708 static const struct attribute_group tty_dev_attr_group
= {
2709 .attrs
= tty_dev_attrs
,
2713 * uart_add_one_port - attach a driver-defined port structure
2714 * @drv: pointer to the uart low level driver structure for this port
2715 * @uport: uart port structure to use for this port.
2717 * This allows the driver to register its own uart_port structure
2718 * with the core driver. The main purpose is to allow the low
2719 * level uart drivers to expand uart_port, rather than having yet
2720 * more levels of structures.
2722 int uart_add_one_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2724 struct uart_state
*state
;
2725 struct tty_port
*port
;
2727 struct device
*tty_dev
;
2730 BUG_ON(in_interrupt());
2732 if (uport
->line
>= drv
->nr
)
2735 state
= drv
->state
+ uport
->line
;
2736 port
= &state
->port
;
2738 mutex_lock(&port_mutex
);
2739 mutex_lock(&port
->mutex
);
2740 if (state
->uart_port
) {
2745 /* Link the port to the driver state table and vice versa */
2746 atomic_set(&state
->refcount
, 1);
2747 init_waitqueue_head(&state
->remove_wait
);
2748 state
->uart_port
= uport
;
2749 uport
->state
= state
;
2751 state
->pm_state
= UART_PM_STATE_UNDEFINED
;
2752 uport
->cons
= drv
->cons
;
2753 uport
->minor
= drv
->tty_driver
->minor_start
+ uport
->line
;
2756 * If this port is a console, then the spinlock is already
2759 if (!(uart_console(uport
) && (uport
->cons
->flags
& CON_ENABLED
))) {
2760 spin_lock_init(&uport
->lock
);
2761 lockdep_set_class(&uport
->lock
, &port_lock_key
);
2763 if (uport
->cons
&& uport
->dev
)
2764 of_console_check(uport
->dev
->of_node
, uport
->cons
->name
, uport
->line
);
2766 uart_configure_port(drv
, state
, uport
);
2768 port
->console
= uart_console(uport
);
2771 if (uport
->attr_group
)
2774 uport
->tty_groups
= kcalloc(num_groups
, sizeof(*uport
->tty_groups
),
2776 if (!uport
->tty_groups
) {
2780 uport
->tty_groups
[0] = &tty_dev_attr_group
;
2781 if (uport
->attr_group
)
2782 uport
->tty_groups
[1] = uport
->attr_group
;
2785 * Register the port whether it's detected or not. This allows
2786 * setserial to be used to alter this port's parameters.
2788 tty_dev
= tty_port_register_device_attr(port
, drv
->tty_driver
,
2789 uport
->line
, uport
->dev
, port
, uport
->tty_groups
);
2790 if (likely(!IS_ERR(tty_dev
))) {
2791 device_set_wakeup_capable(tty_dev
, 1);
2793 dev_err(uport
->dev
, "Cannot register tty device on line %d\n",
2798 * Ensure UPF_DEAD is not set.
2800 uport
->flags
&= ~UPF_DEAD
;
2803 mutex_unlock(&port
->mutex
);
2804 mutex_unlock(&port_mutex
);
2810 * uart_remove_one_port - detach a driver defined port structure
2811 * @drv: pointer to the uart low level driver structure for this port
2812 * @uport: uart port structure for this port
2814 * This unhooks (and hangs up) the specified port structure from the
2815 * core driver. No further calls will be made to the low-level code
2818 int uart_remove_one_port(struct uart_driver
*drv
, struct uart_port
*uport
)
2820 struct uart_state
*state
= drv
->state
+ uport
->line
;
2821 struct tty_port
*port
= &state
->port
;
2822 struct uart_port
*uart_port
;
2823 struct tty_struct
*tty
;
2826 BUG_ON(in_interrupt());
2828 mutex_lock(&port_mutex
);
2831 * Mark the port "dead" - this prevents any opens from
2832 * succeeding while we shut down the port.
2834 mutex_lock(&port
->mutex
);
2835 uart_port
= uart_port_check(state
);
2836 if (uart_port
!= uport
)
2837 dev_alert(uport
->dev
, "Removing wrong port: %p != %p\n",
2841 mutex_unlock(&port
->mutex
);
2845 uport
->flags
|= UPF_DEAD
;
2846 mutex_unlock(&port
->mutex
);
2849 * Remove the devices from the tty layer
2851 tty_unregister_device(drv
->tty_driver
, uport
->line
);
2853 tty
= tty_port_tty_get(port
);
2855 tty_vhangup(port
->tty
);
2860 * If the port is used as a console, unregister it
2862 if (uart_console(uport
))
2863 unregister_console(uport
->cons
);
2866 * Free the port IO and memory resources, if any.
2868 if (uport
->type
!= PORT_UNKNOWN
&& uport
->ops
->release_port
)
2869 uport
->ops
->release_port(uport
);
2870 kfree(uport
->tty_groups
);
2873 * Indicate that there isn't a port here anymore.
2875 uport
->type
= PORT_UNKNOWN
;
2877 mutex_lock(&port
->mutex
);
2878 WARN_ON(atomic_dec_return(&state
->refcount
) < 0);
2879 wait_event(state
->remove_wait
, !atomic_read(&state
->refcount
));
2880 state
->uart_port
= NULL
;
2881 mutex_unlock(&port
->mutex
);
2883 mutex_unlock(&port_mutex
);
2889 * Are the two ports equivalent?
2891 int uart_match_port(struct uart_port
*port1
, struct uart_port
*port2
)
2893 if (port1
->iotype
!= port2
->iotype
)
2896 switch (port1
->iotype
) {
2898 return (port1
->iobase
== port2
->iobase
);
2900 return (port1
->iobase
== port2
->iobase
) &&
2901 (port1
->hub6
== port2
->hub6
);
2908 return (port1
->mapbase
== port2
->mapbase
);
2912 EXPORT_SYMBOL(uart_match_port
);
2915 * uart_handle_dcd_change - handle a change of carrier detect state
2916 * @uport: uart_port structure for the open port
2917 * @status: new carrier detect status, nonzero if active
2919 * Caller must hold uport->lock
2921 void uart_handle_dcd_change(struct uart_port
*uport
, unsigned int status
)
2923 struct tty_port
*port
= &uport
->state
->port
;
2924 struct tty_struct
*tty
= port
->tty
;
2925 struct tty_ldisc
*ld
;
2927 lockdep_assert_held_once(&uport
->lock
);
2930 ld
= tty_ldisc_ref(tty
);
2932 if (ld
->ops
->dcd_change
)
2933 ld
->ops
->dcd_change(tty
, status
);
2934 tty_ldisc_deref(ld
);
2938 uport
->icount
.dcd
++;
2940 if (uart_dcd_enabled(uport
)) {
2942 wake_up_interruptible(&port
->open_wait
);
2947 EXPORT_SYMBOL_GPL(uart_handle_dcd_change
);
2950 * uart_handle_cts_change - handle a change of clear-to-send state
2951 * @uport: uart_port structure for the open port
2952 * @status: new clear to send status, nonzero if active
2954 * Caller must hold uport->lock
2956 void uart_handle_cts_change(struct uart_port
*uport
, unsigned int status
)
2958 lockdep_assert_held_once(&uport
->lock
);
2960 uport
->icount
.cts
++;
2962 if (uart_softcts_mode(uport
)) {
2963 if (uport
->hw_stopped
) {
2965 uport
->hw_stopped
= 0;
2966 uport
->ops
->start_tx(uport
);
2967 uart_write_wakeup(uport
);
2971 uport
->hw_stopped
= 1;
2972 uport
->ops
->stop_tx(uport
);
2978 EXPORT_SYMBOL_GPL(uart_handle_cts_change
);
2981 * uart_insert_char - push a char to the uart layer
2983 * User is responsible to call tty_flip_buffer_push when they are done with
2986 * @port: corresponding port
2987 * @status: state of the serial port RX buffer (LSR for 8250)
2988 * @overrun: mask of overrun bits in @status
2989 * @ch: character to push
2990 * @flag: flag for the character (see TTY_NORMAL and friends)
2992 void uart_insert_char(struct uart_port
*port
, unsigned int status
,
2993 unsigned int overrun
, unsigned int ch
, unsigned int flag
)
2995 struct tty_port
*tport
= &port
->state
->port
;
2997 if ((status
& port
->ignore_status_mask
& ~overrun
) == 0)
2998 if (tty_insert_flip_char(tport
, ch
, flag
) == 0)
2999 ++port
->icount
.buf_overrun
;
3002 * Overrun is special. Since it's reported immediately,
3003 * it doesn't affect the current character.
3005 if (status
& ~port
->ignore_status_mask
& overrun
)
3006 if (tty_insert_flip_char(tport
, 0, TTY_OVERRUN
) == 0)
3007 ++port
->icount
.buf_overrun
;
3009 EXPORT_SYMBOL_GPL(uart_insert_char
);
3011 EXPORT_SYMBOL(uart_write_wakeup
);
3012 EXPORT_SYMBOL(uart_register_driver
);
3013 EXPORT_SYMBOL(uart_unregister_driver
);
3014 EXPORT_SYMBOL(uart_suspend_port
);
3015 EXPORT_SYMBOL(uart_resume_port
);
3016 EXPORT_SYMBOL(uart_add_one_port
);
3017 EXPORT_SYMBOL(uart_remove_one_port
);
3019 MODULE_DESCRIPTION("Serial driver core");
3020 MODULE_LICENSE("GPL");