2 * linux/drivers/char/core.c
4 * Driver core for serial ports
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
8 * Copyright 1999 ARM Limited
9 * Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 #include <linux/module.h>
26 #include <linux/tty.h>
27 #include <linux/slab.h>
28 #include <linux/init.h>
29 #include <linux/console.h>
30 #include <linux/serial_core.h>
31 #include <linux/smp_lock.h>
32 #include <linux/device.h>
33 #include <linux/serial.h> /* for serial_state and serial_icounter_struct */
34 #include <linux/delay.h>
35 #include <linux/mutex.h>
38 #include <asm/uaccess.h>
39 #if 1 // add by Victor Yu. 02-09-2007
40 #include <asm/arch/moxa.h>
41 #include <asm/arch/gpio.h>
48 #define DPRINTK(x...) printk(x)
50 #define DPRINTK(x...) do { } while (0)
54 * This is used to lock changes in serial line configuration.
56 static DEFINE_MUTEX(port_mutex
);
59 * lockdep: port->lock is initialized in two places, but we
60 * want only one lock-class:
62 static struct lock_class_key port_lock_key
;
64 #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
66 #define uart_users(state) ((state)->count + ((state)->info ? (state)->info->blocked_open : 0))
68 #ifdef CONFIG_SERIAL_CORE_CONSOLE
69 #define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line)
71 #define uart_console(port) (0)
74 static void uart_change_speed(struct uart_state
*state
, struct termios
*old_termios
);
75 static void uart_wait_until_sent(struct tty_struct
*tty
, int timeout
);
76 static void uart_change_pm(struct uart_state
*state
, int pm_state
);
79 * This routine is used by the interrupt handler to schedule processing in
80 * the software interrupt portion of the driver.
82 void uart_write_wakeup(struct uart_port
*port
)
84 struct uart_info
*info
= port
->info
;
86 * This means you called this function _after_ the port was
87 * closed. No cookie for you.
90 tasklet_schedule(&info
->tlet
);
93 static void uart_stop(struct tty_struct
*tty
)
95 struct uart_state
*state
= tty
->driver_data
;
96 struct uart_port
*port
= state
->port
;
99 spin_lock_irqsave(&port
->lock
, flags
);
100 port
->ops
->stop_tx(port
);
101 spin_unlock_irqrestore(&port
->lock
, flags
);
104 static void __uart_start(struct tty_struct
*tty
)
106 struct uart_state
*state
= tty
->driver_data
;
107 struct uart_port
*port
= state
->port
;
109 if (!uart_circ_empty(&state
->info
->xmit
) && state
->info
->xmit
.buf
&&
110 !tty
->stopped
&& !tty
->hw_stopped
)
111 port
->ops
->start_tx(port
);
114 static void uart_start(struct tty_struct
*tty
)
116 struct uart_state
*state
= tty
->driver_data
;
117 struct uart_port
*port
= state
->port
;
120 spin_lock_irqsave(&port
->lock
, flags
);
122 spin_unlock_irqrestore(&port
->lock
, flags
);
125 static void uart_tasklet_action(unsigned long data
)
127 struct uart_state
*state
= (struct uart_state
*)data
;
128 tty_wakeup(state
->info
->tty
);
132 uart_update_mctrl(struct uart_port
*port
, unsigned int set
, unsigned int clear
)
137 spin_lock_irqsave(&port
->lock
, flags
);
139 port
->mctrl
= (old
& ~clear
) | set
;
140 if (old
!= port
->mctrl
)
141 port
->ops
->set_mctrl(port
, port
->mctrl
);
142 spin_unlock_irqrestore(&port
->lock
, flags
);
145 #define uart_set_mctrl(port,set) uart_update_mctrl(port,set,0)
146 #define uart_clear_mctrl(port,clear) uart_update_mctrl(port,0,clear)
149 * Startup the port. This will be called once per open. All calls
150 * will be serialised by the per-port semaphore.
152 static int uart_startup(struct uart_state
*state
, int init_hw
)
154 struct uart_info
*info
= state
->info
;
155 struct uart_port
*port
= state
->port
;
159 if (info
->flags
& UIF_INITIALIZED
)
163 * Set the TTY IO error marker - we will only clear this
164 * once we have successfully opened the port. Also set
165 * up the tty->alt_speed kludge
167 set_bit(TTY_IO_ERROR
, &info
->tty
->flags
);
169 if (port
->type
== PORT_UNKNOWN
)
173 * Initialise and allocate the transmit and temporary
176 if (!info
->xmit
.buf
) {
177 page
= get_zeroed_page(GFP_KERNEL
);
181 info
->xmit
.buf
= (unsigned char *) page
;
182 uart_circ_clear(&info
->xmit
);
185 retval
= port
->ops
->startup(port
);
189 * Initialise the hardware port settings.
191 uart_change_speed(state
, NULL
);
194 * Setup the RTS and DTR signals once the
195 * port is open and ready to respond.
197 if (info
->tty
->termios
->c_cflag
& CBAUD
)
198 uart_set_mctrl(port
, TIOCM_RTS
| TIOCM_DTR
);
201 if (info
->flags
& UIF_CTS_FLOW
) {
202 spin_lock_irq(&port
->lock
);
203 if (!(port
->ops
->get_mctrl(port
) & TIOCM_CTS
))
204 info
->tty
->hw_stopped
= 1;
205 spin_unlock_irq(&port
->lock
);
208 info
->flags
|= UIF_INITIALIZED
;
210 clear_bit(TTY_IO_ERROR
, &info
->tty
->flags
);
213 if (retval
&& capable(CAP_SYS_ADMIN
))
220 * This routine will shutdown a serial port; interrupts are disabled, and
221 * DTR is dropped if the hangup on close termio flag is on. Calls to
222 * uart_shutdown are serialised by the per-port semaphore.
224 static void uart_shutdown(struct uart_state
*state
)
226 struct uart_info
*info
= state
->info
;
227 struct uart_port
*port
= state
->port
;
230 * Set the TTY IO error marker
233 set_bit(TTY_IO_ERROR
, &info
->tty
->flags
);
235 if (info
->flags
& UIF_INITIALIZED
) {
236 info
->flags
&= ~UIF_INITIALIZED
;
239 * Turn off DTR and RTS early.
241 if (!info
->tty
|| (info
->tty
->termios
->c_cflag
& HUPCL
))
242 uart_clear_mctrl(port
, TIOCM_DTR
| TIOCM_RTS
);
245 * clear delta_msr_wait queue to avoid mem leaks: we may free
246 * the irq here so the queue might never be woken up. Note
247 * that we won't end up waiting on delta_msr_wait again since
248 * any outstanding file descriptors should be pointing at
249 * hung_up_tty_fops now.
251 wake_up_interruptible(&info
->delta_msr_wait
);
254 * Free the IRQ and disable the port.
256 port
->ops
->shutdown(port
);
259 * Ensure that the IRQ handler isn't running on another CPU.
261 synchronize_irq(port
->irq
);
265 * kill off our tasklet
267 tasklet_kill(&info
->tlet
);
270 * Free the transmit buffer page.
272 if (info
->xmit
.buf
) {
273 free_page((unsigned long)info
->xmit
.buf
);
274 info
->xmit
.buf
= NULL
;
279 * uart_update_timeout - update per-port FIFO timeout.
280 * @port: uart_port structure describing the port
281 * @cflag: termios cflag value
282 * @baud: speed of the port
284 * Set the port FIFO timeout value. The @cflag value should
285 * reflect the actual hardware settings.
288 uart_update_timeout(struct uart_port
*port
, unsigned int cflag
,
293 /* byte size and parity */
294 switch (cflag
& CSIZE
) {
315 * The total number of bits to be transmitted in the fifo.
317 bits
= bits
* port
->fifosize
;
320 * Figure the timeout to send the above number of bits.
321 * Add .02 seconds of slop
323 port
->timeout
= (HZ
* bits
) / baud
+ HZ
/50;
326 EXPORT_SYMBOL(uart_update_timeout
);
329 * uart_get_baud_rate - return baud rate for a particular port
330 * @port: uart_port structure describing the port in question.
331 * @termios: desired termios settings.
332 * @old: old termios (or NULL)
333 * @min: minimum acceptable baud rate
334 * @max: maximum acceptable baud rate
336 * Decode the termios structure into a numeric baud rate,
337 * taking account of the magic 38400 baud rate (with spd_*
338 * flags), and mapping the %B0 rate to 9600 baud.
340 * If the new baud rate is invalid, try the old termios setting.
341 * If it's still invalid, we try 9600 baud.
343 * Update the @termios structure to reflect the baud rate
344 * we're actually going to be using.
347 uart_get_baud_rate(struct uart_port
*port
, struct termios
*termios
,
348 struct termios
*old
, unsigned int min
, unsigned int max
)
350 unsigned int try, baud
, altbaud
= 38400;
351 upf_t flags
= port
->flags
& UPF_SPD_MASK
;
353 if (flags
== UPF_SPD_HI
)
355 if (flags
== UPF_SPD_VHI
)
357 if (flags
== UPF_SPD_SHI
)
359 if (flags
== UPF_SPD_WARP
)
362 for (try = 0; try < 2; try++) {
363 baud
= tty_termios_baud_rate(termios
);
366 * The spd_hi, spd_vhi, spd_shi, spd_warp kludge...
373 * Special case: B0 rate.
378 if (baud
>= min
&& baud
<= max
)
382 * Oops, the quotient was zero. Try again with
383 * the old baud rate if possible.
385 termios
->c_cflag
&= ~CBAUD
;
387 termios
->c_cflag
|= old
->c_cflag
& CBAUD
;
393 * As a last resort, if the quotient is zero,
394 * default to 9600 bps
396 termios
->c_cflag
|= B9600
;
402 EXPORT_SYMBOL(uart_get_baud_rate
);
405 * uart_get_divisor - return uart clock divisor
406 * @port: uart_port structure describing the port.
407 * @baud: desired baud rate
409 * Calculate the uart clock divisor for the port.
412 uart_get_divisor(struct uart_port
*port
, unsigned int baud
)
417 * Old custom speed handling.
419 if (baud
== 38400 && (port
->flags
& UPF_SPD_MASK
) == UPF_SPD_CUST
)
420 quot
= port
->custom_divisor
;
422 quot
= (port
->uartclk
+ (8 * baud
)) / (16 * baud
);
427 EXPORT_SYMBOL(uart_get_divisor
);
430 uart_change_speed(struct uart_state
*state
, struct termios
*old_termios
)
432 struct tty_struct
*tty
= state
->info
->tty
;
433 struct uart_port
*port
= state
->port
;
434 struct termios
*termios
;
437 * If we have no tty, termios, or the port does not exist,
438 * then we can't set the parameters for this port.
440 if (!tty
|| !tty
->termios
|| port
->type
== PORT_UNKNOWN
)
443 termios
= tty
->termios
;
446 * Set flags based on termios cflag
448 if (termios
->c_cflag
& CRTSCTS
)
449 state
->info
->flags
|= UIF_CTS_FLOW
;
451 state
->info
->flags
&= ~UIF_CTS_FLOW
;
453 if (termios
->c_cflag
& CLOCAL
)
454 state
->info
->flags
&= ~UIF_CHECK_CD
;
456 state
->info
->flags
|= UIF_CHECK_CD
;
458 port
->ops
->set_termios(port
, termios
, old_termios
);
462 __uart_put_char(struct uart_port
*port
, struct circ_buf
*circ
, unsigned char c
)
469 spin_lock_irqsave(&port
->lock
, flags
);
470 if (uart_circ_chars_free(circ
) != 0) {
471 circ
->buf
[circ
->head
] = c
;
472 circ
->head
= (circ
->head
+ 1) & (UART_XMIT_SIZE
- 1);
474 spin_unlock_irqrestore(&port
->lock
, flags
);
477 static void uart_put_char(struct tty_struct
*tty
, unsigned char ch
)
479 struct uart_state
*state
= tty
->driver_data
;
481 __uart_put_char(state
->port
, &state
->info
->xmit
, ch
);
484 static void uart_flush_chars(struct tty_struct
*tty
)
490 uart_write(struct tty_struct
*tty
, const unsigned char *buf
, int count
)
492 struct uart_state
*state
= tty
->driver_data
;
493 struct uart_port
*port
;
494 struct circ_buf
*circ
;
499 * This means you called this function _after_ the port was
500 * closed. No cookie for you.
502 if (!state
|| !state
->info
) {
508 circ
= &state
->info
->xmit
;
513 spin_lock_irqsave(&port
->lock
, flags
);
515 c
= CIRC_SPACE_TO_END(circ
->head
, circ
->tail
, UART_XMIT_SIZE
);
520 memcpy(circ
->buf
+ circ
->head
, buf
, c
);
521 circ
->head
= (circ
->head
+ c
) & (UART_XMIT_SIZE
- 1);
526 spin_unlock_irqrestore(&port
->lock
, flags
);
532 static int uart_write_room(struct tty_struct
*tty
)
534 struct uart_state
*state
= tty
->driver_data
;
536 return uart_circ_chars_free(&state
->info
->xmit
);
539 static int uart_chars_in_buffer(struct tty_struct
*tty
)
541 struct uart_state
*state
= tty
->driver_data
;
543 return uart_circ_chars_pending(&state
->info
->xmit
);
546 static void uart_flush_buffer(struct tty_struct
*tty
)
548 struct uart_state
*state
= tty
->driver_data
;
549 struct uart_port
*port
= state
->port
;
553 * This means you called this function _after_ the port was
554 * closed. No cookie for you.
556 if (!state
|| !state
->info
) {
561 DPRINTK("uart_flush_buffer(%d) called\n", tty
->index
);
563 spin_lock_irqsave(&port
->lock
, flags
);
564 uart_circ_clear(&state
->info
->xmit
);
565 spin_unlock_irqrestore(&port
->lock
, flags
);
570 * This function is used to send a high-priority XON/XOFF character to
573 static void uart_send_xchar(struct tty_struct
*tty
, char ch
)
575 struct uart_state
*state
= tty
->driver_data
;
576 struct uart_port
*port
= state
->port
;
579 if (port
->ops
->send_xchar
)
580 port
->ops
->send_xchar(port
, ch
);
584 spin_lock_irqsave(&port
->lock
, flags
);
585 port
->ops
->start_tx(port
);
586 spin_unlock_irqrestore(&port
->lock
, flags
);
591 static void uart_throttle(struct tty_struct
*tty
)
593 struct uart_state
*state
= tty
->driver_data
;
596 uart_send_xchar(tty
, STOP_CHAR(tty
));
598 if (tty
->termios
->c_cflag
& CRTSCTS
)
599 uart_clear_mctrl(state
->port
, TIOCM_RTS
);
602 static void uart_unthrottle(struct tty_struct
*tty
)
604 struct uart_state
*state
= tty
->driver_data
;
605 struct uart_port
*port
= state
->port
;
611 uart_send_xchar(tty
, START_CHAR(tty
));
614 if (tty
->termios
->c_cflag
& CRTSCTS
)
615 uart_set_mctrl(port
, TIOCM_RTS
);
618 static int uart_get_info(struct uart_state
*state
,
619 struct serial_struct __user
*retinfo
)
621 struct uart_port
*port
= state
->port
;
622 struct serial_struct tmp
;
624 memset(&tmp
, 0, sizeof(tmp
));
625 tmp
.type
= port
->type
;
626 tmp
.line
= port
->line
;
627 tmp
.port
= port
->iobase
;
628 if (HIGH_BITS_OFFSET
)
629 tmp
.port_high
= (long) port
->iobase
>> HIGH_BITS_OFFSET
;
631 tmp
.flags
= port
->flags
;
632 tmp
.xmit_fifo_size
= port
->fifosize
;
633 tmp
.baud_base
= port
->uartclk
/ 16;
634 tmp
.close_delay
= state
->close_delay
/ 10;
635 tmp
.closing_wait
= state
->closing_wait
== USF_CLOSING_WAIT_NONE
?
636 ASYNC_CLOSING_WAIT_NONE
:
637 state
->closing_wait
/ 10;
638 tmp
.custom_divisor
= port
->custom_divisor
;
639 tmp
.hub6
= port
->hub6
;
640 tmp
.io_type
= port
->iotype
;
641 tmp
.iomem_reg_shift
= port
->regshift
;
642 tmp
.iomem_base
= (void *)port
->mapbase
;
644 if (copy_to_user(retinfo
, &tmp
, sizeof(*retinfo
)))
649 static int uart_set_info(struct uart_state
*state
,
650 struct serial_struct __user
*newinfo
)
652 struct serial_struct new_serial
;
653 struct uart_port
*port
= state
->port
;
654 unsigned long new_port
;
655 unsigned int change_irq
, change_port
, closing_wait
;
656 unsigned int old_custom_divisor
, close_delay
;
657 upf_t old_flags
, new_flags
;
660 if (copy_from_user(&new_serial
, newinfo
, sizeof(new_serial
)))
663 new_port
= new_serial
.port
;
664 if (HIGH_BITS_OFFSET
)
665 new_port
+= (unsigned long) new_serial
.port_high
<< HIGH_BITS_OFFSET
;
667 new_serial
.irq
= irq_canonicalize(new_serial
.irq
);
668 close_delay
= new_serial
.close_delay
* 10;
669 closing_wait
= new_serial
.closing_wait
== ASYNC_CLOSING_WAIT_NONE
?
670 USF_CLOSING_WAIT_NONE
: new_serial
.closing_wait
* 10;
673 * This semaphore protects state->count. It is also
674 * very useful to prevent opens. Also, take the
675 * port configuration semaphore to make sure that a
676 * module insertion/removal doesn't change anything
679 mutex_lock(&state
->mutex
);
681 change_irq
= new_serial
.irq
!= port
->irq
;
684 * Since changing the 'type' of the port changes its resource
685 * allocations, we should treat type changes the same as
688 change_port
= new_port
!= port
->iobase
||
689 (unsigned long)new_serial
.iomem_base
!= port
->mapbase
||
690 new_serial
.hub6
!= port
->hub6
||
691 new_serial
.io_type
!= port
->iotype
||
692 new_serial
.iomem_reg_shift
!= port
->regshift
||
693 new_serial
.type
!= port
->type
;
695 old_flags
= port
->flags
;
696 new_flags
= new_serial
.flags
;
697 old_custom_divisor
= port
->custom_divisor
;
699 if (!capable(CAP_SYS_ADMIN
)) {
701 if (change_irq
|| change_port
||
702 (new_serial
.baud_base
!= port
->uartclk
/ 16) ||
703 (close_delay
!= state
->close_delay
) ||
704 (closing_wait
!= state
->closing_wait
) ||
705 (new_serial
.xmit_fifo_size
&&
706 new_serial
.xmit_fifo_size
!= port
->fifosize
) ||
707 (((new_flags
^ old_flags
) & ~UPF_USR_MASK
) != 0))
709 port
->flags
= ((port
->flags
& ~UPF_USR_MASK
) |
710 (new_flags
& UPF_USR_MASK
));
711 port
->custom_divisor
= new_serial
.custom_divisor
;
716 * Ask the low level driver to verify the settings.
718 if (port
->ops
->verify_port
)
719 retval
= port
->ops
->verify_port(port
, &new_serial
);
721 if ((new_serial
.irq
>= NR_IRQS
) || (new_serial
.irq
< 0) ||
722 (new_serial
.baud_base
< 9600))
728 if (change_port
|| change_irq
) {
732 * Make sure that we are the sole user of this port.
734 if (uart_users(state
) > 1)
738 * We need to shutdown the serial port at the old
739 * port/type/irq combination.
741 uart_shutdown(state
);
745 unsigned long old_iobase
, old_mapbase
;
746 unsigned int old_type
, old_iotype
, old_hub6
, old_shift
;
748 old_iobase
= port
->iobase
;
749 old_mapbase
= port
->mapbase
;
750 old_type
= port
->type
;
751 old_hub6
= port
->hub6
;
752 old_iotype
= port
->iotype
;
753 old_shift
= port
->regshift
;
756 * Free and release old regions
758 if (old_type
!= PORT_UNKNOWN
)
759 port
->ops
->release_port(port
);
761 port
->iobase
= new_port
;
762 port
->type
= new_serial
.type
;
763 port
->hub6
= new_serial
.hub6
;
764 port
->iotype
= new_serial
.io_type
;
765 port
->regshift
= new_serial
.iomem_reg_shift
;
766 port
->mapbase
= (unsigned long)new_serial
.iomem_base
;
769 * Claim and map the new regions
771 if (port
->type
!= PORT_UNKNOWN
) {
772 retval
= port
->ops
->request_port(port
);
774 /* Always success - Jean II */
779 * If we fail to request resources for the
780 * new port, try to restore the old settings.
782 if (retval
&& old_type
!= PORT_UNKNOWN
) {
783 port
->iobase
= old_iobase
;
784 port
->type
= old_type
;
785 port
->hub6
= old_hub6
;
786 port
->iotype
= old_iotype
;
787 port
->regshift
= old_shift
;
788 port
->mapbase
= old_mapbase
;
789 retval
= port
->ops
->request_port(port
);
791 * If we failed to restore the old settings,
795 port
->type
= PORT_UNKNOWN
;
801 goto exit
; // Added to return the correct error -Ram Gupta
805 port
->irq
= new_serial
.irq
;
806 port
->uartclk
= new_serial
.baud_base
* 16;
807 port
->flags
= (port
->flags
& ~UPF_CHANGE_MASK
) |
808 (new_flags
& UPF_CHANGE_MASK
);
809 port
->custom_divisor
= new_serial
.custom_divisor
;
810 state
->close_delay
= close_delay
;
811 state
->closing_wait
= closing_wait
;
812 if (new_serial
.xmit_fifo_size
)
813 port
->fifosize
= new_serial
.xmit_fifo_size
;
814 if (state
->info
->tty
)
815 state
->info
->tty
->low_latency
=
816 (port
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
820 if (port
->type
== PORT_UNKNOWN
)
822 if (state
->info
->flags
& UIF_INITIALIZED
) {
823 if (((old_flags
^ port
->flags
) & UPF_SPD_MASK
) ||
824 old_custom_divisor
!= port
->custom_divisor
) {
826 * If they're setting up a custom divisor or speed,
827 * instead of clearing it, then bitch about it. No
828 * need to rate-limit; it's CAP_SYS_ADMIN only.
830 if (port
->flags
& UPF_SPD_MASK
) {
833 "%s sets custom speed on %s. This "
834 "is deprecated.\n", current
->comm
,
835 tty_name(state
->info
->tty
, buf
));
837 uart_change_speed(state
, NULL
);
840 retval
= uart_startup(state
, 1);
842 mutex_unlock(&state
->mutex
);
848 * uart_get_lsr_info - get line status register info.
849 * Note: uart_ioctl protects us against hangups.
851 static int uart_get_lsr_info(struct uart_state
*state
,
852 unsigned int __user
*value
)
854 struct uart_port
*port
= state
->port
;
857 result
= port
->ops
->tx_empty(port
);
860 * If we're about to load something into the transmit
861 * register, we'll pretend the transmitter isn't empty to
862 * avoid a race condition (depending on when the transmit
863 * interrupt happens).
866 ((uart_circ_chars_pending(&state
->info
->xmit
) > 0) &&
867 !state
->info
->tty
->stopped
&& !state
->info
->tty
->hw_stopped
))
868 result
&= ~TIOCSER_TEMT
;
870 return put_user(result
, value
);
873 static int uart_tiocmget(struct tty_struct
*tty
, struct file
*file
)
875 struct uart_state
*state
= tty
->driver_data
;
876 struct uart_port
*port
= state
->port
;
879 mutex_lock(&state
->mutex
);
880 if ((!file
|| !tty_hung_up_p(file
)) &&
881 !(tty
->flags
& (1 << TTY_IO_ERROR
))) {
882 result
= port
->mctrl
;
884 spin_lock_irq(&port
->lock
);
885 result
|= port
->ops
->get_mctrl(port
);
886 spin_unlock_irq(&port
->lock
);
888 mutex_unlock(&state
->mutex
);
894 uart_tiocmset(struct tty_struct
*tty
, struct file
*file
,
895 unsigned int set
, unsigned int clear
)
897 struct uart_state
*state
= tty
->driver_data
;
898 struct uart_port
*port
= state
->port
;
901 mutex_lock(&state
->mutex
);
902 if ((!file
|| !tty_hung_up_p(file
)) &&
903 !(tty
->flags
& (1 << TTY_IO_ERROR
))) {
904 uart_update_mctrl(port
, set
, clear
);
907 mutex_unlock(&state
->mutex
);
911 static void uart_break_ctl(struct tty_struct
*tty
, int break_state
)
913 struct uart_state
*state
= tty
->driver_data
;
914 struct uart_port
*port
= state
->port
;
916 BUG_ON(!kernel_locked());
918 mutex_lock(&state
->mutex
);
920 if (port
->type
!= PORT_UNKNOWN
)
921 port
->ops
->break_ctl(port
, break_state
);
923 mutex_unlock(&state
->mutex
);
926 static int uart_do_autoconfig(struct uart_state
*state
)
928 struct uart_port
*port
= state
->port
;
931 if (!capable(CAP_SYS_ADMIN
))
935 * Take the per-port semaphore. This prevents count from
936 * changing, and hence any extra opens of the port while
937 * we're auto-configuring.
939 if (mutex_lock_interruptible(&state
->mutex
))
943 if (uart_users(state
) == 1) {
944 uart_shutdown(state
);
947 * If we already have a port type configured,
948 * we must release its resources.
950 if (port
->type
!= PORT_UNKNOWN
)
951 port
->ops
->release_port(port
);
953 flags
= UART_CONFIG_TYPE
;
954 if (port
->flags
& UPF_AUTO_IRQ
)
955 flags
|= UART_CONFIG_IRQ
;
958 * This will claim the ports resources if
961 port
->ops
->config_port(port
, flags
);
963 ret
= uart_startup(state
, 1);
965 mutex_unlock(&state
->mutex
);
970 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
971 * - mask passed in arg for lines of interest
972 * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
973 * Caller should use TIOCGICOUNT to see which one it was
976 uart_wait_modem_status(struct uart_state
*state
, unsigned long arg
)
978 struct uart_port
*port
= state
->port
;
979 DECLARE_WAITQUEUE(wait
, current
);
980 struct uart_icount cprev
, cnow
;
984 * note the counters on entry
986 spin_lock_irq(&port
->lock
);
987 memcpy(&cprev
, &port
->icount
, sizeof(struct uart_icount
));
990 * Force modem status interrupts on
992 port
->ops
->enable_ms(port
);
993 spin_unlock_irq(&port
->lock
);
995 add_wait_queue(&state
->info
->delta_msr_wait
, &wait
);
997 spin_lock_irq(&port
->lock
);
998 memcpy(&cnow
, &port
->icount
, sizeof(struct uart_icount
));
999 spin_unlock_irq(&port
->lock
);
1001 set_current_state(TASK_INTERRUPTIBLE
);
1003 if (((arg
& TIOCM_RNG
) && (cnow
.rng
!= cprev
.rng
)) ||
1004 ((arg
& TIOCM_DSR
) && (cnow
.dsr
!= cprev
.dsr
)) ||
1005 ((arg
& TIOCM_CD
) && (cnow
.dcd
!= cprev
.dcd
)) ||
1006 ((arg
& TIOCM_CTS
) && (cnow
.cts
!= cprev
.cts
))) {
1013 /* see if a signal did it */
1014 if (signal_pending(current
)) {
1022 current
->state
= TASK_RUNNING
;
1023 remove_wait_queue(&state
->info
->delta_msr_wait
, &wait
);
1029 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
1030 * Return: write counters to the user passed counter struct
1031 * NB: both 1->0 and 0->1 transitions are counted except for
1032 * RI where only 0->1 is counted.
1034 static int uart_get_count(struct uart_state
*state
,
1035 struct serial_icounter_struct __user
*icnt
)
1037 struct serial_icounter_struct icount
;
1038 struct uart_icount cnow
;
1039 struct uart_port
*port
= state
->port
;
1041 spin_lock_irq(&port
->lock
);
1042 memcpy(&cnow
, &port
->icount
, sizeof(struct uart_icount
));
1043 spin_unlock_irq(&port
->lock
);
1045 icount
.cts
= cnow
.cts
;
1046 icount
.dsr
= cnow
.dsr
;
1047 icount
.rng
= cnow
.rng
;
1048 icount
.dcd
= cnow
.dcd
;
1049 icount
.rx
= cnow
.rx
;
1050 icount
.tx
= cnow
.tx
;
1051 icount
.frame
= cnow
.frame
;
1052 icount
.overrun
= cnow
.overrun
;
1053 icount
.parity
= cnow
.parity
;
1054 icount
.brk
= cnow
.brk
;
1055 icount
.buf_overrun
= cnow
.buf_overrun
;
1057 return copy_to_user(icnt
, &icount
, sizeof(icount
)) ? -EFAULT
: 0;
1060 #if 1 // add by Victor Yu. 02-09-2007
1061 #define PIO(x) (1<<x)
1062 #if 1 // add by Victor Yu. 07-26-2007
1063 #if defined(CONFIG_ARCH_W311_TEST)
1064 #define SW_READY_LED PIO(4)
1065 #define BEEPER_IO PIO(27)
1067 #define SW_READY_LED PIO(27)
1068 #define BEEPER_IO PIO(24)
1070 static int readyledflag
=0;
1072 static void beep_sound(unsigned long arg
)
1074 unsigned long ms
,ss
;
1075 static spinlock_t beeplock
;
1079 ms
= ms
/ (1000/HZ
);
1081 ms
= (ms
* 1000) / (1000000/HZ
);
1085 if ( readyledflag
== 0 ) { // add by Victor Yu. 07-26-2007
1086 // enable beeper GPIO output
1087 mcpu_gpio_mp_set(BEEPER_IO
);
1088 mcpu_gpio_inout(BEEPER_IO
, MCPU_GPIO_OUTPUT
);
1090 /* light ready led after jump into user space */
1091 mcpu_gpio_mp_set(SW_READY_LED
);
1092 mcpu_gpio_inout(SW_READY_LED
, MCPU_GPIO_OUTPUT
);
1093 mcpu_gpio_set(SW_READY_LED
, MCPU_GPIO_LOW
);
1097 spin_lock(&beeplock
);
1099 mcpu_gpio_set(BEEPER_IO
, MCPU_GPIO_HIGH
);
1102 while( !time_after(jiffies
,ms
)) {
1103 set_current_state(TASK_INTERRUPTIBLE
);
1104 schedule_timeout(ss
);
1105 if (signal_pending(current
))
1110 mcpu_gpio_set(BEEPER_IO
, MCPU_GPIO_LOW
);
1111 spin_unlock(&beeplock
);
1116 * Called via sys_ioctl under the BKL. We can use spin_lock_irq() here.
1119 uart_ioctl(struct tty_struct
*tty
, struct file
*filp
, unsigned int cmd
,
1122 struct uart_state
*state
= tty
->driver_data
;
1123 void __user
*uarg
= (void __user
*)arg
;
1124 int ret
= -ENOIOCTLCMD
;
1126 BUG_ON(!kernel_locked());
1129 * These ioctls don't rely on the hardware to be present.
1132 #if 1 // add by Victor Yu. 02-09-2007
1139 ret
= uart_get_info(state
, uarg
);
1143 ret
= uart_set_info(state
, uarg
);
1147 ret
= uart_do_autoconfig(state
);
1150 case TIOCSERGWILD
: /* obsolete */
1151 case TIOCSERSWILD
: /* obsolete */
1156 if (ret
!= -ENOIOCTLCMD
)
1159 if (tty
->flags
& (1 << TTY_IO_ERROR
)) {
1165 * The following should only be used when hardware is present.
1169 ret
= uart_wait_modem_status(state
, arg
);
1173 ret
= uart_get_count(state
, uarg
);
1177 if (ret
!= -ENOIOCTLCMD
)
1180 mutex_lock(&state
->mutex
);
1182 if (tty_hung_up_p(filp
)) {
1188 * All these rely on hardware being present and need to be
1189 * protected against the tty being hung up.
1192 case TIOCSERGETLSR
: /* Get line status register */
1193 ret
= uart_get_lsr_info(state
, uarg
);
1197 struct uart_port
*port
= state
->port
;
1198 if (port
->ops
->ioctl
)
1199 ret
= port
->ops
->ioctl(port
, cmd
, arg
);
1204 mutex_unlock(&state
->mutex
);
1209 static void uart_set_termios(struct tty_struct
*tty
, struct termios
*old_termios
)
1211 struct uart_state
*state
= tty
->driver_data
;
1212 unsigned long flags
;
1213 unsigned int cflag
= tty
->termios
->c_cflag
;
1215 BUG_ON(!kernel_locked());
1218 * These are the bits that are used to setup various
1219 * flags in the low level driver.
1221 #define RELEVANT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
1223 if ((cflag
^ old_termios
->c_cflag
) == 0 &&
1224 RELEVANT_IFLAG(tty
->termios
->c_iflag
^ old_termios
->c_iflag
) == 0)
1227 uart_change_speed(state
, old_termios
);
1229 /* Handle transition to B0 status */
1230 if ((old_termios
->c_cflag
& CBAUD
) && !(cflag
& CBAUD
))
1231 uart_clear_mctrl(state
->port
, TIOCM_RTS
| TIOCM_DTR
);
1233 /* Handle transition away from B0 status */
1234 if (!(old_termios
->c_cflag
& CBAUD
) && (cflag
& CBAUD
)) {
1235 unsigned int mask
= TIOCM_DTR
;
1236 if (!(cflag
& CRTSCTS
) ||
1237 !test_bit(TTY_THROTTLED
, &tty
->flags
))
1239 uart_set_mctrl(state
->port
, mask
);
1242 /* Handle turning off CRTSCTS */
1243 if ((old_termios
->c_cflag
& CRTSCTS
) && !(cflag
& CRTSCTS
)) {
1244 spin_lock_irqsave(&state
->port
->lock
, flags
);
1245 tty
->hw_stopped
= 0;
1247 spin_unlock_irqrestore(&state
->port
->lock
, flags
);
1250 /* Handle turning on CRTSCTS */
1251 if (!(old_termios
->c_cflag
& CRTSCTS
) && (cflag
& CRTSCTS
)) {
1252 spin_lock_irqsave(&state
->port
->lock
, flags
);
1253 if (!(state
->port
->ops
->get_mctrl(state
->port
) & TIOCM_CTS
)) {
1254 tty
->hw_stopped
= 1;
1255 state
->port
->ops
->stop_tx(state
->port
);
1257 spin_unlock_irqrestore(&state
->port
->lock
, flags
);
1262 * No need to wake up processes in open wait, since they
1263 * sample the CLOCAL flag once, and don't recheck it.
1264 * XXX It's not clear whether the current behavior is correct
1265 * or not. Hence, this may change.....
1267 if (!(old_termios
->c_cflag
& CLOCAL
) &&
1268 (tty
->termios
->c_cflag
& CLOCAL
))
1269 wake_up_interruptible(&state
->info
->open_wait
);
1274 * In 2.4.5, calls to this will be serialized via the BKL in
1275 * linux/drivers/char/tty_io.c:tty_release()
1276 * linux/drivers/char/tty_io.c:do_tty_handup()
1278 static void uart_close(struct tty_struct
*tty
, struct file
*filp
)
1280 struct uart_state
*state
= tty
->driver_data
;
1281 struct uart_port
*port
;
1283 BUG_ON(!kernel_locked());
1285 if (!state
|| !state
->port
)
1290 DPRINTK("uart_close(%d) called\n", port
->line
);
1292 mutex_lock(&state
->mutex
);
1294 if (tty_hung_up_p(filp
))
1297 if ((tty
->count
== 1) && (state
->count
!= 1)) {
1299 * Uh, oh. tty->count is 1, which means that the tty
1300 * structure will be freed. state->count should always
1301 * be one in these conditions. If it's greater than
1302 * one, we've got real problems, since it means the
1303 * serial port won't be shutdown.
1305 printk(KERN_ERR
"uart_close: bad serial port count; tty->count is 1, "
1306 "state->count is %d\n", state
->count
);
1309 if (--state
->count
< 0) {
1310 printk(KERN_ERR
"uart_close: bad serial port count for %s: %d\n",
1311 tty
->name
, state
->count
);
1318 * Now we wait for the transmit buffer to clear; and we notify
1319 * the line discipline to only process XON/XOFF characters by
1320 * setting tty->closing.
1324 if (state
->closing_wait
!= USF_CLOSING_WAIT_NONE
)
1325 tty_wait_until_sent(tty
, msecs_to_jiffies(state
->closing_wait
));
1328 * At this point, we stop accepting input. To do this, we
1329 * disable the receive line status interrupts.
1331 if (state
->info
->flags
& UIF_INITIALIZED
) {
1332 unsigned long flags
;
1333 spin_lock_irqsave(&port
->lock
, flags
);
1334 port
->ops
->stop_rx(port
);
1335 spin_unlock_irqrestore(&port
->lock
, flags
);
1337 * Before we drop DTR, make sure the UART transmitter
1338 * has completely drained; this is especially
1339 * important if there is a transmit FIFO!
1341 uart_wait_until_sent(tty
, port
->timeout
);
1344 uart_shutdown(state
);
1345 uart_flush_buffer(tty
);
1347 tty_ldisc_flush(tty
);
1350 state
->info
->tty
= NULL
;
1352 if (state
->info
->blocked_open
) {
1353 if (state
->close_delay
)
1354 msleep_interruptible(state
->close_delay
);
1355 } else if (!uart_console(port
)) {
1356 uart_change_pm(state
, 3);
1360 * Wake up anyone trying to open this port.
1362 state
->info
->flags
&= ~UIF_NORMAL_ACTIVE
;
1363 wake_up_interruptible(&state
->info
->open_wait
);
1366 mutex_unlock(&state
->mutex
);
1369 static void uart_wait_until_sent(struct tty_struct
*tty
, int timeout
)
1371 struct uart_state
*state
= tty
->driver_data
;
1372 struct uart_port
*port
= state
->port
;
1373 unsigned long char_time
, expire
;
1375 BUG_ON(!kernel_locked());
1377 if (port
->type
== PORT_UNKNOWN
|| port
->fifosize
== 0)
1381 * Set the check interval to be 1/5 of the estimated time to
1382 * send a single character, and make it at least 1. The check
1383 * interval should also be less than the timeout.
1385 * Note: we have to use pretty tight timings here to satisfy
1388 char_time
= (port
->timeout
- HZ
/50) / port
->fifosize
;
1389 char_time
= char_time
/ 5;
1392 if (timeout
&& timeout
< char_time
)
1393 char_time
= timeout
;
1396 * If the transmitter hasn't cleared in twice the approximate
1397 * amount of time to send the entire FIFO, it probably won't
1398 * ever clear. This assumes the UART isn't doing flow
1399 * control, which is currently the case. Hence, if it ever
1400 * takes longer than port->timeout, this is probably due to a
1401 * UART bug of some kind. So, we clamp the timeout parameter at
1404 if (timeout
== 0 || timeout
> 2 * port
->timeout
)
1405 timeout
= 2 * port
->timeout
;
1407 expire
= jiffies
+ timeout
;
1409 DPRINTK("uart_wait_until_sent(%d), jiffies=%lu, expire=%lu...\n",
1410 port
->line
, jiffies
, expire
);
1413 * Check whether the transmitter is empty every 'char_time'.
1414 * 'timeout' / 'expire' give us the maximum amount of time
1417 while (!port
->ops
->tx_empty(port
)) {
1418 msleep_interruptible(jiffies_to_msecs(char_time
));
1419 if (signal_pending(current
))
1421 if (time_after(jiffies
, expire
))
1424 set_current_state(TASK_RUNNING
); /* might not be needed */
1428 * This is called with the BKL held in
1429 * linux/drivers/char/tty_io.c:do_tty_hangup()
1430 * We're called from the eventd thread, so we can sleep for
1431 * a _short_ time only.
1433 static void uart_hangup(struct tty_struct
*tty
)
1435 struct uart_state
*state
= tty
->driver_data
;
1437 BUG_ON(!kernel_locked());
1438 DPRINTK("uart_hangup(%d)\n", state
->port
->line
);
1440 mutex_lock(&state
->mutex
);
1441 if (state
->info
&& state
->info
->flags
& UIF_NORMAL_ACTIVE
) {
1442 uart_flush_buffer(tty
);
1443 uart_shutdown(state
);
1445 state
->info
->flags
&= ~UIF_NORMAL_ACTIVE
;
1446 state
->info
->tty
= NULL
;
1447 wake_up_interruptible(&state
->info
->open_wait
);
1448 wake_up_interruptible(&state
->info
->delta_msr_wait
);
1450 mutex_unlock(&state
->mutex
);
1454 * Copy across the serial console cflag setting into the termios settings
1455 * for the initial open of the port. This allows continuity between the
1456 * kernel settings, and the settings init adopts when it opens the port
1457 * for the first time.
1459 static void uart_update_termios(struct uart_state
*state
)
1461 struct tty_struct
*tty
= state
->info
->tty
;
1462 struct uart_port
*port
= state
->port
;
1464 if (uart_console(port
) && port
->cons
->cflag
) {
1465 tty
->termios
->c_cflag
= port
->cons
->cflag
;
1466 port
->cons
->cflag
= 0;
1470 * If the device failed to grab its irq resources,
1471 * or some other error occurred, don't try to talk
1472 * to the port hardware.
1474 if (!(tty
->flags
& (1 << TTY_IO_ERROR
))) {
1476 * Make termios settings take effect.
1478 uart_change_speed(state
, NULL
);
1481 * And finally enable the RTS and DTR signals.
1483 if (tty
->termios
->c_cflag
& CBAUD
)
1484 uart_set_mctrl(port
, TIOCM_DTR
| TIOCM_RTS
);
1489 * Block the open until the port is ready. We must be called with
1490 * the per-port semaphore held.
1493 uart_block_til_ready(struct file
*filp
, struct uart_state
*state
)
1495 DECLARE_WAITQUEUE(wait
, current
);
1496 struct uart_info
*info
= state
->info
;
1497 struct uart_port
*port
= state
->port
;
1500 info
->blocked_open
++;
1503 add_wait_queue(&info
->open_wait
, &wait
);
1505 set_current_state(TASK_INTERRUPTIBLE
);
1508 * If we have been hung up, tell userspace/restart open.
1510 if (tty_hung_up_p(filp
) || info
->tty
== NULL
)
1514 * If the port has been closed, tell userspace/restart open.
1516 if (!(info
->flags
& UIF_INITIALIZED
))
1520 * If non-blocking mode is set, or CLOCAL mode is set,
1521 * we don't want to wait for the modem status lines to
1522 * indicate that the port is ready.
1524 * Also, if the port is not enabled/configured, we want
1525 * to allow the open to succeed here. Note that we will
1526 * have set TTY_IO_ERROR for a non-existant port.
1528 if ((filp
->f_flags
& O_NONBLOCK
) ||
1529 (info
->tty
->termios
->c_cflag
& CLOCAL
) ||
1530 (info
->tty
->flags
& (1 << TTY_IO_ERROR
))) {
1535 * Set DTR to allow modem to know we're waiting. Do
1536 * not set RTS here - we want to make sure we catch
1537 * the data from the modem.
1539 if (info
->tty
->termios
->c_cflag
& CBAUD
)
1540 uart_set_mctrl(port
, TIOCM_DTR
);
1543 * and wait for the carrier to indicate that the
1544 * modem is ready for us.
1546 spin_lock_irq(&port
->lock
);
1547 port
->ops
->enable_ms(port
);
1548 mctrl
= port
->ops
->get_mctrl(port
);
1549 spin_unlock_irq(&port
->lock
);
1550 if (mctrl
& TIOCM_CAR
)
1553 mutex_unlock(&state
->mutex
);
1555 mutex_lock(&state
->mutex
);
1557 if (signal_pending(current
))
1560 set_current_state(TASK_RUNNING
);
1561 remove_wait_queue(&info
->open_wait
, &wait
);
1564 info
->blocked_open
--;
1566 if (signal_pending(current
))
1567 return -ERESTARTSYS
;
1569 if (!info
->tty
|| tty_hung_up_p(filp
))
1575 static struct uart_state
*uart_get(struct uart_driver
*drv
, int line
)
1577 struct uart_state
*state
;
1580 state
= drv
->state
+ line
;
1581 if (mutex_lock_interruptible(&state
->mutex
)) {
1587 if (!state
->port
|| state
->port
->flags
& UPF_DEAD
) {
1593 state
->info
= kmalloc(sizeof(struct uart_info
), GFP_KERNEL
);
1595 memset(state
->info
, 0, sizeof(struct uart_info
));
1596 init_waitqueue_head(&state
->info
->open_wait
);
1597 init_waitqueue_head(&state
->info
->delta_msr_wait
);
1600 * Link the info into the other structures.
1602 state
->port
->info
= state
->info
;
1604 tasklet_init(&state
->info
->tlet
, uart_tasklet_action
,
1605 (unsigned long)state
);
1615 mutex_unlock(&state
->mutex
);
1617 return ERR_PTR(ret
);
1621 * In 2.4.5, calls to uart_open are serialised by the BKL in
1622 * linux/fs/devices.c:chrdev_open()
1623 * Note that if this fails, then uart_close() _will_ be called.
1625 * In time, we want to scrap the "opening nonpresent ports"
1626 * behaviour and implement an alternative way for setserial
1627 * to set base addresses/ports/types. This will allow us to
1628 * get rid of a certain amount of extra tests.
1630 static int uart_open(struct tty_struct
*tty
, struct file
*filp
)
1632 struct uart_driver
*drv
= (struct uart_driver
*)tty
->driver
->driver_state
;
1633 struct uart_state
*state
;
1634 int retval
, line
= tty
->index
;
1636 BUG_ON(!kernel_locked());
1637 DPRINTK("uart_open(%d) called\n", line
);
1640 * tty->driver->num won't change, so we won't fail here with
1641 * tty->driver_data set to something non-NULL (and therefore
1642 * we won't get caught by uart_close()).
1645 if (line
>= tty
->driver
->num
)
1649 * We take the semaphore inside uart_get to guarantee that we won't
1650 * be re-entered while allocating the info structure, or while we
1651 * request any IRQs that the driver may need. This also has the nice
1652 * side-effect that it delays the action of uart_hangup, so we can
1653 * guarantee that info->tty will always contain something reasonable.
1655 state
= uart_get(drv
, line
);
1656 if (IS_ERR(state
)) {
1657 retval
= PTR_ERR(state
);
1662 * Once we set tty->driver_data here, we are guaranteed that
1663 * uart_close() will decrement the driver module use count.
1664 * Any failures from here onwards should not touch the count.
1666 tty
->driver_data
= state
;
1667 tty
->low_latency
= (state
->port
->flags
& UPF_LOW_LATENCY
) ? 1 : 0;
1669 state
->info
->tty
= tty
;
1672 * If the port is in the middle of closing, bail out now.
1674 if (tty_hung_up_p(filp
)) {
1677 mutex_unlock(&state
->mutex
);
1682 * Make sure the device is in D0 state.
1684 if (state
->count
== 1)
1685 uart_change_pm(state
, 0);
1688 * Start up the serial port.
1690 retval
= uart_startup(state
, 0);
1693 * If we succeeded, wait until the port is ready.
1696 retval
= uart_block_til_ready(filp
, state
);
1697 mutex_unlock(&state
->mutex
);
1700 * If this is the first open to succeed, adjust things to suit.
1702 if (retval
== 0 && !(state
->info
->flags
& UIF_NORMAL_ACTIVE
)) {
1703 state
->info
->flags
|= UIF_NORMAL_ACTIVE
;
1705 uart_update_termios(state
);
1712 static const char *uart_type(struct uart_port
*port
)
1714 const char *str
= NULL
;
1716 if (port
->ops
->type
)
1717 str
= port
->ops
->type(port
);
1725 #ifdef CONFIG_PROC_FS
1727 static int uart_line_info(char *buf
, struct uart_driver
*drv
, int i
)
1729 struct uart_state
*state
= drv
->state
+ i
;
1730 struct uart_port
*port
= state
->port
;
1732 unsigned int status
;
1738 mmio
= port
->iotype
>= UPIO_MEM
;
1739 ret
= sprintf(buf
, "%d: uart:%s %s%08lX irq:%d",
1740 port
->line
, uart_type(port
),
1741 mmio
? "mmio:0x" : "port:",
1742 mmio
? port
->mapbase
: (unsigned long) port
->iobase
,
1745 if (port
->type
== PORT_UNKNOWN
) {
1750 if(capable(CAP_SYS_ADMIN
))
1752 spin_lock_irq(&port
->lock
);
1753 status
= port
->ops
->get_mctrl(port
);
1754 spin_unlock_irq(&port
->lock
);
1756 ret
+= sprintf(buf
+ ret
, " tx:%d rx:%d",
1757 port
->icount
.tx
, port
->icount
.rx
);
1758 if (port
->icount
.frame
)
1759 ret
+= sprintf(buf
+ ret
, " fe:%d",
1760 port
->icount
.frame
);
1761 if (port
->icount
.parity
)
1762 ret
+= sprintf(buf
+ ret
, " pe:%d",
1763 port
->icount
.parity
);
1764 if (port
->icount
.brk
)
1765 ret
+= sprintf(buf
+ ret
, " brk:%d",
1767 if (port
->icount
.overrun
)
1768 ret
+= sprintf(buf
+ ret
, " oe:%d",
1769 port
->icount
.overrun
);
1771 #define INFOBIT(bit,str) \
1772 if (port->mctrl & (bit)) \
1773 strncat(stat_buf, (str), sizeof(stat_buf) - \
1774 strlen(stat_buf) - 2)
1775 #define STATBIT(bit,str) \
1776 if (status & (bit)) \
1777 strncat(stat_buf, (str), sizeof(stat_buf) - \
1778 strlen(stat_buf) - 2)
1782 INFOBIT(TIOCM_RTS
, "|RTS");
1783 STATBIT(TIOCM_CTS
, "|CTS");
1784 INFOBIT(TIOCM_DTR
, "|DTR");
1785 STATBIT(TIOCM_DSR
, "|DSR");
1786 STATBIT(TIOCM_CAR
, "|CD");
1787 STATBIT(TIOCM_RNG
, "|RI");
1790 strcat(stat_buf
, "\n");
1792 ret
+= sprintf(buf
+ ret
, stat_buf
);
1802 static int uart_read_proc(char *page
, char **start
, off_t off
,
1803 int count
, int *eof
, void *data
)
1805 struct tty_driver
*ttydrv
= data
;
1806 struct uart_driver
*drv
= ttydrv
->driver_state
;
1810 len
+= sprintf(page
, "serinfo:1.0 driver%s%s revision:%s\n",
1812 for (i
= 0; i
< drv
->nr
&& len
< PAGE_SIZE
- 96; i
++) {
1813 l
= uart_line_info(page
+ len
, drv
, i
);
1815 if (len
+ begin
> off
+ count
)
1817 if (len
+ begin
< off
) {
1824 if (off
>= len
+ begin
)
1826 *start
= page
+ (off
- begin
);
1827 return (count
< begin
+ len
- off
) ? count
: (begin
+ len
- off
);
1831 #ifdef CONFIG_SERIAL_CORE_CONSOLE
1833 * uart_console_write - write a console message to a serial port
1834 * @port: the port to write the message
1835 * @s: array of characters
1836 * @count: number of characters in string to write
1837 * @write: function to write character to port
1839 void uart_console_write(struct uart_port
*port
, const char *s
,
1841 void (*putchar
)(struct uart_port
*, int))
1845 for (i
= 0; i
< count
; i
++, s
++) {
1847 putchar(port
, '\r');
1851 EXPORT_SYMBOL_GPL(uart_console_write
);
1854 * Check whether an invalid uart number has been specified, and
1855 * if so, search for the first available port that does have
1858 struct uart_port
* __init
1859 uart_get_console(struct uart_port
*ports
, int nr
, struct console
*co
)
1861 int idx
= co
->index
;
1863 if (idx
< 0 || idx
>= nr
|| (ports
[idx
].iobase
== 0 &&
1864 ports
[idx
].membase
== NULL
))
1865 for (idx
= 0; idx
< nr
; idx
++)
1866 if (ports
[idx
].iobase
!= 0 ||
1867 ports
[idx
].membase
!= NULL
)
1876 * uart_parse_options - Parse serial port baud/parity/bits/flow contro.
1877 * @options: pointer to option string
1878 * @baud: pointer to an 'int' variable for the baud rate.
1879 * @parity: pointer to an 'int' variable for the parity.
1880 * @bits: pointer to an 'int' variable for the number of data bits.
1881 * @flow: pointer to an 'int' variable for the flow control character.
1883 * uart_parse_options decodes a string containing the serial console
1884 * options. The format of the string is <baud><parity><bits><flow>,
1888 uart_parse_options(char *options
, int *baud
, int *parity
, int *bits
, int *flow
)
1892 *baud
= simple_strtoul(s
, NULL
, 10);
1893 while (*s
>= '0' && *s
<= '9')
1908 static const struct baud_rates baud_rates
[] = {
1909 { 921600, B921600
},
1910 { 460800, B460800
},
1911 { 230400, B230400
},
1912 { 115200, B115200
},
1924 * uart_set_options - setup the serial console parameters
1925 * @port: pointer to the serial ports uart_port structure
1926 * @co: console pointer
1928 * @parity: parity character - 'n' (none), 'o' (odd), 'e' (even)
1929 * @bits: number of data bits
1930 * @flow: flow control character - 'r' (rts)
1933 uart_set_options(struct uart_port
*port
, struct console
*co
,
1934 int baud
, int parity
, int bits
, int flow
)
1936 struct termios termios
;
1940 * Ensure that the serial console lock is initialised
1943 spin_lock_init(&port
->lock
);
1944 lockdep_set_class(&port
->lock
, &port_lock_key
);
1946 memset(&termios
, 0, sizeof(struct termios
));
1948 termios
.c_cflag
= CREAD
| HUPCL
| CLOCAL
;
1951 * Construct a cflag setting.
1953 for (i
= 0; baud_rates
[i
].rate
; i
++)
1954 if (baud_rates
[i
].rate
<= baud
)
1957 termios
.c_cflag
|= baud_rates
[i
].cflag
;
1960 termios
.c_cflag
|= CS7
;
1962 termios
.c_cflag
|= CS8
;
1966 termios
.c_cflag
|= PARODD
;
1969 termios
.c_cflag
|= PARENB
;
1974 termios
.c_cflag
|= CRTSCTS
;
1976 port
->ops
->set_termios(port
, &termios
, NULL
);
1977 co
->cflag
= termios
.c_cflag
;
1981 #endif /* CONFIG_SERIAL_CORE_CONSOLE */
1983 static void uart_change_pm(struct uart_state
*state
, int pm_state
)
1985 struct uart_port
*port
= state
->port
;
1987 if (state
->pm_state
!= pm_state
) {
1989 port
->ops
->pm(port
, pm_state
, state
->pm_state
);
1990 state
->pm_state
= pm_state
;
1994 int uart_suspend_port(struct uart_driver
*drv
, struct uart_port
*port
)
1996 struct uart_state
*state
= drv
->state
+ port
->line
;
1998 mutex_lock(&state
->mutex
);
2000 #ifdef CONFIG_DISABLE_CONSOLE_SUSPEND
2001 if (uart_console(port
)) {
2002 mutex_unlock(&state
->mutex
);
2007 if (state
->info
&& state
->info
->flags
& UIF_INITIALIZED
) {
2008 const struct uart_ops
*ops
= port
->ops
;
2010 state
->info
->flags
= (state
->info
->flags
& ~UIF_INITIALIZED
)
2013 spin_lock_irq(&port
->lock
);
2015 ops
->set_mctrl(port
, 0);
2017 spin_unlock_irq(&port
->lock
);
2020 * Wait for the transmitter to empty.
2022 while (!ops
->tx_empty(port
)) {
2026 ops
->shutdown(port
);
2030 * Disable the console device before suspending.
2032 if (uart_console(port
))
2033 console_stop(port
->cons
);
2035 uart_change_pm(state
, 3);
2037 mutex_unlock(&state
->mutex
);
2042 int uart_resume_port(struct uart_driver
*drv
, struct uart_port
*port
)
2044 struct uart_state
*state
= drv
->state
+ port
->line
;
2046 mutex_lock(&state
->mutex
);
2048 #ifdef CONFIG_DISABLE_CONSOLE_SUSPEND
2049 if (uart_console(port
)) {
2050 mutex_unlock(&state
->mutex
);
2055 uart_change_pm(state
, 0);
2058 * Re-enable the console device after suspending.
2060 if (uart_console(port
)) {
2061 struct termios termios
;
2064 * First try to use the console cflag setting.
2066 memset(&termios
, 0, sizeof(struct termios
));
2067 termios
.c_cflag
= port
->cons
->cflag
;
2070 * If that's unset, use the tty termios setting.
2072 if (state
->info
&& state
->info
->tty
&& termios
.c_cflag
== 0)
2073 termios
= *state
->info
->tty
->termios
;
2075 port
->ops
->set_termios(port
, &termios
, NULL
);
2076 console_start(port
->cons
);
2079 if (state
->info
&& state
->info
->flags
& UIF_SUSPENDED
) {
2080 const struct uart_ops
*ops
= port
->ops
;
2083 ops
->set_mctrl(port
, 0);
2084 ret
= ops
->startup(port
);
2086 uart_change_speed(state
, NULL
);
2087 spin_lock_irq(&port
->lock
);
2088 ops
->set_mctrl(port
, port
->mctrl
);
2089 ops
->start_tx(port
);
2090 spin_unlock_irq(&port
->lock
);
2091 state
->info
->flags
|= UIF_INITIALIZED
;
2094 * Failed to resume - maybe hardware went away?
2095 * Clear the "initialized" flag so we won't try
2096 * to call the low level drivers shutdown method.
2098 uart_shutdown(state
);
2101 state
->info
->flags
&= ~UIF_SUSPENDED
;
2104 mutex_unlock(&state
->mutex
);
2110 uart_report_port(struct uart_driver
*drv
, struct uart_port
*port
)
2114 switch (port
->iotype
) {
2116 snprintf(address
, sizeof(address
),
2117 "I/O 0x%x", port
->iobase
);
2120 snprintf(address
, sizeof(address
),
2121 "I/O 0x%x offset 0x%x", port
->iobase
, port
->hub6
);
2127 snprintf(address
, sizeof(address
),
2128 "MMIO 0x%lx", port
->mapbase
);
2131 strlcpy(address
, "*unknown*", sizeof(address
));
2135 printk(KERN_INFO
"%s%s%s%d at %s (irq = %d) is a %s\n",
2136 port
->dev
? port
->dev
->bus_id
: "",
2137 port
->dev
? ": " : "",
2138 drv
->dev_name
, port
->line
, address
, port
->irq
, uart_type(port
));
2142 uart_configure_port(struct uart_driver
*drv
, struct uart_state
*state
,
2143 struct uart_port
*port
)
2148 * If there isn't a port here, don't do anything further.
2150 if (!port
->iobase
&& !port
->mapbase
&& !port
->membase
)
2154 * Now do the auto configuration stuff. Note that config_port
2155 * is expected to claim the resources and map the port for us.
2157 flags
= UART_CONFIG_TYPE
;
2158 if (port
->flags
& UPF_AUTO_IRQ
)
2159 flags
|= UART_CONFIG_IRQ
;
2160 if (port
->flags
& UPF_BOOT_AUTOCONF
) {
2161 port
->type
= PORT_UNKNOWN
;
2162 port
->ops
->config_port(port
, flags
);
2165 if (port
->type
!= PORT_UNKNOWN
) {
2166 unsigned long flags
;
2168 uart_report_port(drv
, port
);
2171 * Ensure that the modem control lines are de-activated.
2172 * We probably don't need a spinlock around this, but
2174 spin_lock_irqsave(&port
->lock
, flags
);
2175 port
->ops
->set_mctrl(port
, 0);
2176 spin_unlock_irqrestore(&port
->lock
, flags
);
2179 * Power down all ports by default, except the
2180 * console if we have one.
2182 if (!uart_console(port
))
2183 uart_change_pm(state
, 3);
2187 static const struct tty_operations uart_ops
= {
2189 .close
= uart_close
,
2190 .write
= uart_write
,
2191 .put_char
= uart_put_char
,
2192 .flush_chars
= uart_flush_chars
,
2193 .write_room
= uart_write_room
,
2194 .chars_in_buffer
= uart_chars_in_buffer
,
2195 .flush_buffer
= uart_flush_buffer
,
2196 .ioctl
= uart_ioctl
,
2197 .throttle
= uart_throttle
,
2198 .unthrottle
= uart_unthrottle
,
2199 .send_xchar
= uart_send_xchar
,
2200 .set_termios
= uart_set_termios
,
2202 .start
= uart_start
,
2203 .hangup
= uart_hangup
,
2204 .break_ctl
= uart_break_ctl
,
2205 .wait_until_sent
= uart_wait_until_sent
,
2206 #ifdef CONFIG_PROC_FS
2207 .read_proc
= uart_read_proc
,
2209 .tiocmget
= uart_tiocmget
,
2210 .tiocmset
= uart_tiocmset
,
2214 * uart_register_driver - register a driver with the uart core layer
2215 * @drv: low level driver structure
2217 * Register a uart driver with the core driver. We in turn register
2218 * with the tty layer, and initialise the core driver per-port state.
2220 * We have a proc file in /proc/tty/driver which is named after the
2223 * drv->port should be NULL, and the per-port structures should be
2224 * registered using uart_add_one_port after this call has succeeded.
2226 int uart_register_driver(struct uart_driver
*drv
)
2228 struct tty_driver
*normal
= NULL
;
2234 * Maybe we should be using a slab cache for this, especially if
2235 * we have a large number of ports to handle.
2237 drv
->state
= kmalloc(sizeof(struct uart_state
) * drv
->nr
, GFP_KERNEL
);
2242 memset(drv
->state
, 0, sizeof(struct uart_state
) * drv
->nr
);
2244 normal
= alloc_tty_driver(drv
->nr
);
2248 drv
->tty_driver
= normal
;
2250 normal
->owner
= drv
->owner
;
2251 normal
->driver_name
= drv
->driver_name
;
2252 normal
->name
= drv
->dev_name
;
2253 normal
->major
= drv
->major
;
2254 normal
->minor_start
= drv
->minor
;
2255 normal
->type
= TTY_DRIVER_TYPE_SERIAL
;
2256 normal
->subtype
= SERIAL_TYPE_NORMAL
;
2257 normal
->init_termios
= tty_std_termios
;
2258 normal
->init_termios
.c_cflag
= B9600
| CS8
| CREAD
| HUPCL
| CLOCAL
;
2259 normal
->flags
= TTY_DRIVER_REAL_RAW
| TTY_DRIVER_DYNAMIC_DEV
;
2260 normal
->driver_state
= drv
;
2261 tty_set_operations(normal
, &uart_ops
);
2264 * Initialise the UART state(s).
2266 for (i
= 0; i
< drv
->nr
; i
++) {
2267 struct uart_state
*state
= drv
->state
+ i
;
2269 state
->close_delay
= 500; /* .5 seconds */
2270 state
->closing_wait
= 30000; /* 30 seconds */
2272 mutex_init(&state
->mutex
);
2275 retval
= tty_register_driver(normal
);
2278 put_tty_driver(normal
);
2285 * uart_unregister_driver - remove a driver from the uart core layer
2286 * @drv: low level driver structure
2288 * Remove all references to a driver from the core driver. The low
2289 * level driver must have removed all its ports via the
2290 * uart_remove_one_port() if it registered them with uart_add_one_port().
2291 * (ie, drv->port == NULL)
2293 void uart_unregister_driver(struct uart_driver
*drv
)
2295 struct tty_driver
*p
= drv
->tty_driver
;
2296 tty_unregister_driver(p
);
2299 drv
->tty_driver
= NULL
;
2302 struct tty_driver
*uart_console_device(struct console
*co
, int *index
)
2304 struct uart_driver
*p
= co
->data
;
2306 return p
->tty_driver
;
2310 * uart_add_one_port - attach a driver-defined port structure
2311 * @drv: pointer to the uart low level driver structure for this port
2312 * @port: uart port structure to use for this port.
2314 * This allows the driver to register its own uart_port structure
2315 * with the core driver. The main purpose is to allow the low
2316 * level uart drivers to expand uart_port, rather than having yet
2317 * more levels of structures.
2319 int uart_add_one_port(struct uart_driver
*drv
, struct uart_port
*port
)
2321 struct uart_state
*state
;
2324 BUG_ON(in_interrupt());
2326 if (port
->line
>= drv
->nr
)
2329 state
= drv
->state
+ port
->line
;
2331 mutex_lock(&port_mutex
);
2332 mutex_lock(&state
->mutex
);
2340 port
->cons
= drv
->cons
;
2341 port
->info
= state
->info
;
2344 * If this port is a console, then the spinlock is already
2347 if (!(uart_console(port
) && (port
->cons
->flags
& CON_ENABLED
))) {
2348 spin_lock_init(&port
->lock
);
2349 lockdep_set_class(&port
->lock
, &port_lock_key
);
2352 uart_configure_port(drv
, state
, port
);
2355 * Register the port whether it's detected or not. This allows
2356 * setserial to be used to alter this ports parameters.
2358 tty_register_device(drv
->tty_driver
, port
->line
, port
->dev
);
2361 * If this driver supports console, and it hasn't been
2362 * successfully registered yet, try to re-register it.
2363 * It may be that the port was not available.
2365 if (port
->type
!= PORT_UNKNOWN
&&
2366 port
->cons
&& !(port
->cons
->flags
& CON_ENABLED
))
2367 register_console(port
->cons
);
2370 * Ensure UPF_DEAD is not set.
2372 port
->flags
&= ~UPF_DEAD
;
2375 mutex_unlock(&state
->mutex
);
2376 mutex_unlock(&port_mutex
);
2382 * uart_remove_one_port - detach a driver defined port structure
2383 * @drv: pointer to the uart low level driver structure for this port
2384 * @port: uart port structure for this port
2386 * This unhooks (and hangs up) the specified port structure from the
2387 * core driver. No further calls will be made to the low-level code
2390 int uart_remove_one_port(struct uart_driver
*drv
, struct uart_port
*port
)
2392 struct uart_state
*state
= drv
->state
+ port
->line
;
2393 struct uart_info
*info
;
2395 BUG_ON(in_interrupt());
2397 if (state
->port
!= port
)
2398 printk(KERN_ALERT
"Removing wrong port: %p != %p\n",
2401 mutex_lock(&port_mutex
);
2404 * Mark the port "dead" - this prevents any opens from
2405 * succeeding while we shut down the port.
2407 mutex_lock(&state
->mutex
);
2408 port
->flags
|= UPF_DEAD
;
2409 mutex_unlock(&state
->mutex
);
2412 * Remove the devices from the tty layer
2414 tty_unregister_device(drv
->tty_driver
, port
->line
);
2417 if (info
&& info
->tty
)
2418 tty_vhangup(info
->tty
);
2421 * All users of this port should now be disconnected from
2422 * this driver, and the port shut down. We should be the
2423 * only thread fiddling with this port from now on.
2428 * Free the port IO and memory resources, if any.
2430 if (port
->type
!= PORT_UNKNOWN
)
2431 port
->ops
->release_port(port
);
2434 * Indicate that there isn't a port here anymore.
2436 port
->type
= PORT_UNKNOWN
;
2439 * Kill the tasklet, and free resources.
2442 tasklet_kill(&info
->tlet
);
2447 mutex_unlock(&port_mutex
);
2453 * Are the two ports equivalent?
2455 int uart_match_port(struct uart_port
*port1
, struct uart_port
*port2
)
2457 if (port1
->iotype
!= port2
->iotype
)
2460 switch (port1
->iotype
) {
2462 return (port1
->iobase
== port2
->iobase
);
2464 return (port1
->iobase
== port2
->iobase
) &&
2465 (port1
->hub6
== port2
->hub6
);
2470 return (port1
->mapbase
== port2
->mapbase
);
2474 EXPORT_SYMBOL(uart_match_port
);
2476 EXPORT_SYMBOL(uart_write_wakeup
);
2477 EXPORT_SYMBOL(uart_register_driver
);
2478 EXPORT_SYMBOL(uart_unregister_driver
);
2479 EXPORT_SYMBOL(uart_suspend_port
);
2480 EXPORT_SYMBOL(uart_resume_port
);
2481 EXPORT_SYMBOL(uart_add_one_port
);
2482 EXPORT_SYMBOL(uart_remove_one_port
);
2484 MODULE_DESCRIPTION("Serial driver core");
2485 MODULE_LICENSE("GPL");