2 * linux/drivers/char/atmel_serial.c
4 * Driver for Atmel AT91 / AT32 Serial ports
5 * Copyright (C) 2003 Rick Bronson
7 * Based on drivers/char/serial_sa1100.c, by Deep Blue Solutions Ltd.
8 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * 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/ioport.h>
28 #include <linux/slab.h>
29 #include <linux/init.h>
30 #include <linux/serial.h>
31 #include <linux/clk.h>
32 #include <linux/console.h>
33 #include <linux/sysrq.h>
34 #include <linux/tty_flip.h>
35 #include <linux/platform_device.h>
36 #include <linux/atmel_pdc.h>
37 #include <linux/atmel_serial.h>
41 #include <asm/mach/serial_at91.h>
42 #include <asm/arch/board.h>
45 #include <asm/arch/cpu.h>
46 #include <asm/arch/gpio.h>
49 #if defined(CONFIG_SERIAL_ATMEL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
53 #include <linux/serial_core.h>
55 #ifdef CONFIG_SERIAL_ATMEL_TTYAT
57 /* Use device name ttyAT, major 204 and minor 154-169. This is necessary if we
58 * should coexist with the 8250 driver, such as if we have an external 16C550
60 #define SERIAL_ATMEL_MAJOR 204
61 #define MINOR_START 154
62 #define ATMEL_DEVICENAME "ttyAT"
66 /* Use device name ttyS, major 4, minor 64-68. This is the usual serial port
67 * name, but it is legally reserved for the 8250 driver. */
68 #define SERIAL_ATMEL_MAJOR TTY_MAJOR
69 #define MINOR_START 64
70 #define ATMEL_DEVICENAME "ttyS"
74 #define ATMEL_ISR_PASS_LIMIT 256
76 /* UART registers. CR is write-only, hence no GET macro */
77 #define UART_PUT_CR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_CR)
78 #define UART_GET_MR(port) __raw_readl((port)->membase + ATMEL_US_MR)
79 #define UART_PUT_MR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_MR)
80 #define UART_PUT_IER(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IER)
81 #define UART_PUT_IDR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IDR)
82 #define UART_GET_IMR(port) __raw_readl((port)->membase + ATMEL_US_IMR)
83 #define UART_GET_CSR(port) __raw_readl((port)->membase + ATMEL_US_CSR)
84 #define UART_GET_CHAR(port) __raw_readl((port)->membase + ATMEL_US_RHR)
85 #define UART_PUT_CHAR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_THR)
86 #define UART_GET_BRGR(port) __raw_readl((port)->membase + ATMEL_US_BRGR)
87 #define UART_PUT_BRGR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_BRGR)
88 #define UART_PUT_RTOR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_RTOR)
91 #define UART_PUT_PTCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
92 #define UART_GET_PTSR(port) __raw_readl((port)->membase + ATMEL_PDC_PTSR)
94 #define UART_PUT_RPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RPR)
95 #define UART_GET_RPR(port) __raw_readl((port)->membase + ATMEL_PDC_RPR)
96 #define UART_PUT_RCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RCR)
97 #define UART_PUT_RNPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNPR)
98 #define UART_PUT_RNCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNCR)
100 #define UART_PUT_TPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TPR)
101 #define UART_PUT_TCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TCR)
103 static int (*atmel_open_hook
)(struct uart_port
*);
104 static void (*atmel_close_hook
)(struct uart_port
*);
106 struct atmel_uart_char
{
111 #define ATMEL_SERIAL_RINGSIZE 1024
114 * We wrap our port structure around the generic uart_port.
116 struct atmel_uart_port
{
117 struct uart_port uart
; /* uart */
118 struct clk
*clk
; /* uart clock */
119 unsigned short suspended
; /* is port suspended? */
120 int break_active
; /* break being received */
122 struct tasklet_struct tasklet
;
123 unsigned int irq_status
;
124 unsigned int irq_status_prev
;
126 struct circ_buf rx_ring
;
129 static struct atmel_uart_port atmel_ports
[ATMEL_MAX_UART
];
132 static struct console atmel_console
;
136 * Return TIOCSER_TEMT when transmitter FIFO and Shift register is empty.
138 static u_int
atmel_tx_empty(struct uart_port
*port
)
140 return (UART_GET_CSR(port
) & ATMEL_US_TXEMPTY
) ? TIOCSER_TEMT
: 0;
144 * Set state of the modem control output lines
146 static void atmel_set_mctrl(struct uart_port
*port
, u_int mctrl
)
148 unsigned int control
= 0;
151 #ifdef CONFIG_ARCH_AT91RM9200
152 if (cpu_is_at91rm9200()) {
154 * AT91RM9200 Errata #39: RTS0 is not internally connected
155 * to PA21. We need to drive the pin manually.
157 if (port
->mapbase
== AT91RM9200_BASE_US0
) {
158 if (mctrl
& TIOCM_RTS
)
159 at91_set_gpio_value(AT91_PIN_PA21
, 0);
161 at91_set_gpio_value(AT91_PIN_PA21
, 1);
166 if (mctrl
& TIOCM_RTS
)
167 control
|= ATMEL_US_RTSEN
;
169 control
|= ATMEL_US_RTSDIS
;
171 if (mctrl
& TIOCM_DTR
)
172 control
|= ATMEL_US_DTREN
;
174 control
|= ATMEL_US_DTRDIS
;
176 UART_PUT_CR(port
, control
);
178 /* Local loopback mode? */
179 mode
= UART_GET_MR(port
) & ~ATMEL_US_CHMODE
;
180 if (mctrl
& TIOCM_LOOP
)
181 mode
|= ATMEL_US_CHMODE_LOC_LOOP
;
183 mode
|= ATMEL_US_CHMODE_NORMAL
;
184 UART_PUT_MR(port
, mode
);
188 * Get state of the modem control input lines
190 static u_int
atmel_get_mctrl(struct uart_port
*port
)
192 unsigned int status
, ret
= 0;
194 status
= UART_GET_CSR(port
);
197 * The control signals are active low.
199 if (!(status
& ATMEL_US_DCD
))
201 if (!(status
& ATMEL_US_CTS
))
203 if (!(status
& ATMEL_US_DSR
))
205 if (!(status
& ATMEL_US_RI
))
214 static void atmel_stop_tx(struct uart_port
*port
)
216 UART_PUT_IDR(port
, ATMEL_US_TXRDY
);
220 * Start transmitting.
222 static void atmel_start_tx(struct uart_port
*port
)
224 UART_PUT_IER(port
, ATMEL_US_TXRDY
);
228 * Stop receiving - port is in process of being closed.
230 static void atmel_stop_rx(struct uart_port
*port
)
232 UART_PUT_IDR(port
, ATMEL_US_RXRDY
);
236 * Enable modem status interrupts
238 static void atmel_enable_ms(struct uart_port
*port
)
240 UART_PUT_IER(port
, ATMEL_US_RIIC
| ATMEL_US_DSRIC
241 | ATMEL_US_DCDIC
| ATMEL_US_CTSIC
);
245 * Control the transmission of a break signal
247 static void atmel_break_ctl(struct uart_port
*port
, int break_state
)
249 if (break_state
!= 0)
250 UART_PUT_CR(port
, ATMEL_US_STTBRK
); /* start break */
252 UART_PUT_CR(port
, ATMEL_US_STPBRK
); /* stop break */
256 * Stores the incoming character in the ring buffer
259 atmel_buffer_rx_char(struct uart_port
*port
, unsigned int status
,
262 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
263 struct circ_buf
*ring
= &atmel_port
->rx_ring
;
264 struct atmel_uart_char
*c
;
266 if (!CIRC_SPACE(ring
->head
, ring
->tail
, ATMEL_SERIAL_RINGSIZE
))
267 /* Buffer overflow, ignore char */
270 c
= &((struct atmel_uart_char
*)ring
->buf
)[ring
->head
];
274 /* Make sure the character is stored before we update head. */
277 ring
->head
= (ring
->head
+ 1) & (ATMEL_SERIAL_RINGSIZE
- 1);
281 * Characters received (called from interrupt handler)
283 static void atmel_rx_chars(struct uart_port
*port
)
285 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
286 unsigned int status
, ch
;
288 status
= UART_GET_CSR(port
);
289 while (status
& ATMEL_US_RXRDY
) {
290 ch
= UART_GET_CHAR(port
);
293 * note that the error handling code is
294 * out of the main execution path
296 if (unlikely(status
& (ATMEL_US_PARE
| ATMEL_US_FRAME
297 | ATMEL_US_OVRE
| ATMEL_US_RXBRK
)
298 || atmel_port
->break_active
)) {
301 UART_PUT_CR(port
, ATMEL_US_RSTSTA
);
303 if (status
& ATMEL_US_RXBRK
304 && !atmel_port
->break_active
) {
305 atmel_port
->break_active
= 1;
306 UART_PUT_IER(port
, ATMEL_US_RXBRK
);
309 * This is either the end-of-break
310 * condition or we've received at
311 * least one character without RXBRK
312 * being set. In both cases, the next
313 * RXBRK will indicate start-of-break.
315 UART_PUT_IDR(port
, ATMEL_US_RXBRK
);
316 status
&= ~ATMEL_US_RXBRK
;
317 atmel_port
->break_active
= 0;
321 atmel_buffer_rx_char(port
, status
, ch
);
322 status
= UART_GET_CSR(port
);
325 tasklet_schedule(&atmel_port
->tasklet
);
329 * Transmit characters (called from tasklet with TXRDY interrupt
332 static void atmel_tx_chars(struct uart_port
*port
)
334 struct circ_buf
*xmit
= &port
->info
->xmit
;
336 if (port
->x_char
&& UART_GET_CSR(port
) & ATMEL_US_TXRDY
) {
337 UART_PUT_CHAR(port
, port
->x_char
);
341 if (uart_circ_empty(xmit
) || uart_tx_stopped(port
))
344 while (UART_GET_CSR(port
) & ATMEL_US_TXRDY
) {
345 UART_PUT_CHAR(port
, xmit
->buf
[xmit
->tail
]);
346 xmit
->tail
= (xmit
->tail
+ 1) & (UART_XMIT_SIZE
- 1);
348 if (uart_circ_empty(xmit
))
352 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
353 uart_write_wakeup(port
);
355 if (!uart_circ_empty(xmit
))
356 UART_PUT_IER(port
, ATMEL_US_TXRDY
);
360 * receive interrupt handler.
363 atmel_handle_receive(struct uart_port
*port
, unsigned int pending
)
365 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
367 /* Interrupt receive */
368 if (pending
& ATMEL_US_RXRDY
)
369 atmel_rx_chars(port
);
370 else if (pending
& ATMEL_US_RXBRK
) {
372 * End of break detected. If it came along with a
373 * character, atmel_rx_chars will handle it.
375 UART_PUT_CR(port
, ATMEL_US_RSTSTA
);
376 UART_PUT_IDR(port
, ATMEL_US_RXBRK
);
377 atmel_port
->break_active
= 0;
382 * transmit interrupt handler. (Transmit is IRQF_NODELAY safe)
385 atmel_handle_transmit(struct uart_port
*port
, unsigned int pending
)
387 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
389 /* Interrupt transmit */
390 if (pending
& ATMEL_US_TXRDY
) {
391 UART_PUT_IDR(port
, ATMEL_US_TXRDY
);
392 tasklet_schedule(&atmel_port
->tasklet
);
397 * status flags interrupt handler.
400 atmel_handle_status(struct uart_port
*port
, unsigned int pending
,
403 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
405 if (pending
& (ATMEL_US_RIIC
| ATMEL_US_DSRIC
| ATMEL_US_DCDIC
407 atmel_port
->irq_status
= status
;
408 tasklet_schedule(&atmel_port
->tasklet
);
415 static irqreturn_t
atmel_interrupt(int irq
, void *dev_id
)
417 struct uart_port
*port
= dev_id
;
418 unsigned int status
, pending
, pass_counter
= 0;
420 status
= UART_GET_CSR(port
);
421 pending
= status
& UART_GET_IMR(port
);
423 atmel_handle_receive(port
, pending
);
424 atmel_handle_status(port
, pending
, status
);
425 atmel_handle_transmit(port
, pending
);
427 if (pass_counter
++ > ATMEL_ISR_PASS_LIMIT
)
430 status
= UART_GET_CSR(port
);
431 pending
= status
& UART_GET_IMR(port
);
436 static void atmel_rx_from_ring(struct uart_port
*port
)
438 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
439 struct circ_buf
*ring
= &atmel_port
->rx_ring
;
443 while (ring
->head
!= ring
->tail
) {
444 struct atmel_uart_char c
;
446 /* Make sure c is loaded after head. */
449 c
= ((struct atmel_uart_char
*)ring
->buf
)[ring
->tail
];
451 ring
->tail
= (ring
->tail
+ 1) & (ATMEL_SERIAL_RINGSIZE
- 1);
458 * note that the error handling code is
459 * out of the main execution path
461 if (unlikely(status
& (ATMEL_US_PARE
| ATMEL_US_FRAME
462 | ATMEL_US_OVRE
| ATMEL_US_RXBRK
))) {
463 if (status
& ATMEL_US_RXBRK
) {
464 /* ignore side-effect */
465 status
&= ~(ATMEL_US_PARE
| ATMEL_US_FRAME
);
468 if (uart_handle_break(port
))
471 if (status
& ATMEL_US_PARE
)
472 port
->icount
.parity
++;
473 if (status
& ATMEL_US_FRAME
)
474 port
->icount
.frame
++;
475 if (status
& ATMEL_US_OVRE
)
476 port
->icount
.overrun
++;
478 status
&= port
->read_status_mask
;
480 if (status
& ATMEL_US_RXBRK
)
482 else if (status
& ATMEL_US_PARE
)
484 else if (status
& ATMEL_US_FRAME
)
489 if (uart_handle_sysrq_char(port
, c
.ch
))
492 uart_insert_char(port
, status
, ATMEL_US_OVRE
, c
.ch
, flg
);
496 * Drop the lock here since it might end up calling
497 * uart_start(), which takes the lock.
499 spin_unlock(&port
->lock
);
500 tty_flip_buffer_push(port
->info
->tty
);
501 spin_lock(&port
->lock
);
505 * tasklet handling tty stuff outside the interrupt handler.
507 static void atmel_tasklet_func(unsigned long data
)
509 struct uart_port
*port
= (struct uart_port
*)data
;
510 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
512 unsigned int status_change
;
514 /* The interrupt handler does not take the lock */
515 spin_lock(&port
->lock
);
517 atmel_tx_chars(port
);
519 status
= atmel_port
->irq_status
;
520 status_change
= status
^ atmel_port
->irq_status_prev
;
522 if (status_change
& (ATMEL_US_RI
| ATMEL_US_DSR
523 | ATMEL_US_DCD
| ATMEL_US_CTS
)) {
524 /* TODO: All reads to CSR will clear these interrupts! */
525 if (status_change
& ATMEL_US_RI
)
527 if (status_change
& ATMEL_US_DSR
)
529 if (status_change
& ATMEL_US_DCD
)
530 uart_handle_dcd_change(port
, !(status
& ATMEL_US_DCD
));
531 if (status_change
& ATMEL_US_CTS
)
532 uart_handle_cts_change(port
, !(status
& ATMEL_US_CTS
));
534 wake_up_interruptible(&port
->info
->delta_msr_wait
);
536 atmel_port
->irq_status_prev
= status
;
539 atmel_rx_from_ring(port
);
541 spin_unlock(&port
->lock
);
545 * Perform initialization and enable port for reception
547 static int atmel_startup(struct uart_port
*port
)
552 * Ensure that no interrupts are enabled otherwise when
553 * request_irq() is called we could get stuck trying to
554 * handle an unexpected interrupt
556 UART_PUT_IDR(port
, -1);
561 retval
= request_irq(port
->irq
, atmel_interrupt
, IRQF_SHARED
,
562 "atmel_serial", port
);
564 printk("atmel_serial: atmel_startup - Can't get irq\n");
569 * If there is a specific "open" function (to register
570 * control line interrupts)
572 if (atmel_open_hook
) {
573 retval
= atmel_open_hook(port
);
575 free_irq(port
->irq
, port
);
581 * Finally, enable the serial port
583 UART_PUT_CR(port
, ATMEL_US_RSTSTA
| ATMEL_US_RSTRX
);
584 /* enable xmit & rcvr */
585 UART_PUT_CR(port
, ATMEL_US_TXEN
| ATMEL_US_RXEN
);
587 /* enable receive only */
588 UART_PUT_IER(port
, ATMEL_US_RXRDY
);
596 static void atmel_shutdown(struct uart_port
*port
)
599 * Disable all interrupts, port and break condition.
601 UART_PUT_CR(port
, ATMEL_US_RSTSTA
);
602 UART_PUT_IDR(port
, -1);
607 free_irq(port
->irq
, port
);
610 * If there is a specific "close" function (to unregister
611 * control line interrupts)
613 if (atmel_close_hook
)
614 atmel_close_hook(port
);
618 * Power / Clock management.
620 static void atmel_serial_pm(struct uart_port
*port
, unsigned int state
,
621 unsigned int oldstate
)
623 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
628 * Enable the peripheral clock for this serial port.
629 * This is called on uart_open() or a resume event.
631 clk_enable(atmel_port
->clk
);
635 * Disable the peripheral clock for this serial port.
636 * This is called on uart_close() or a suspend event.
638 clk_disable(atmel_port
->clk
);
641 printk(KERN_ERR
"atmel_serial: unknown pm %d\n", state
);
646 * Change the port parameters
648 static void atmel_set_termios(struct uart_port
*port
, struct ktermios
*termios
,
649 struct ktermios
*old
)
652 unsigned int mode
, imr
, quot
, baud
;
654 /* Get current mode register */
655 mode
= UART_GET_MR(port
) & ~(ATMEL_US_USCLKS
| ATMEL_US_CHRL
656 | ATMEL_US_NBSTOP
| ATMEL_US_PAR
);
658 baud
= uart_get_baud_rate(port
, termios
, old
, 0, port
->uartclk
/ 16);
659 quot
= uart_get_divisor(port
, baud
);
661 if (quot
> 65535) { /* BRGR is 16-bit, so switch to slower clock */
663 mode
|= ATMEL_US_USCLKS_MCK_DIV8
;
667 switch (termios
->c_cflag
& CSIZE
) {
669 mode
|= ATMEL_US_CHRL_5
;
672 mode
|= ATMEL_US_CHRL_6
;
675 mode
|= ATMEL_US_CHRL_7
;
678 mode
|= ATMEL_US_CHRL_8
;
683 if (termios
->c_cflag
& CSTOPB
)
684 mode
|= ATMEL_US_NBSTOP_2
;
687 if (termios
->c_cflag
& PARENB
) {
688 /* Mark or Space parity */
689 if (termios
->c_cflag
& CMSPAR
) {
690 if (termios
->c_cflag
& PARODD
)
691 mode
|= ATMEL_US_PAR_MARK
;
693 mode
|= ATMEL_US_PAR_SPACE
;
694 } else if (termios
->c_cflag
& PARODD
)
695 mode
|= ATMEL_US_PAR_ODD
;
697 mode
|= ATMEL_US_PAR_EVEN
;
699 mode
|= ATMEL_US_PAR_NONE
;
701 spin_lock_irqsave(&port
->lock
, flags
);
703 port
->read_status_mask
= ATMEL_US_OVRE
;
704 if (termios
->c_iflag
& INPCK
)
705 port
->read_status_mask
|= (ATMEL_US_FRAME
| ATMEL_US_PARE
);
706 if (termios
->c_iflag
& (BRKINT
| PARMRK
))
707 port
->read_status_mask
|= ATMEL_US_RXBRK
;
710 * Characters to ignore
712 port
->ignore_status_mask
= 0;
713 if (termios
->c_iflag
& IGNPAR
)
714 port
->ignore_status_mask
|= (ATMEL_US_FRAME
| ATMEL_US_PARE
);
715 if (termios
->c_iflag
& IGNBRK
) {
716 port
->ignore_status_mask
|= ATMEL_US_RXBRK
;
718 * If we're ignoring parity and break indicators,
719 * ignore overruns too (for real raw support).
721 if (termios
->c_iflag
& IGNPAR
)
722 port
->ignore_status_mask
|= ATMEL_US_OVRE
;
724 /* TODO: Ignore all characters if CREAD is set.*/
726 /* update the per-port timeout */
727 uart_update_timeout(port
, termios
->c_cflag
, baud
);
729 /* save/disable interrupts and drain transmitter */
730 imr
= UART_GET_IMR(port
);
731 UART_PUT_IDR(port
, -1);
732 while (!(UART_GET_CSR(port
) & ATMEL_US_TXEMPTY
))
735 /* disable receiver and transmitter */
736 UART_PUT_CR(port
, ATMEL_US_TXDIS
| ATMEL_US_RXDIS
);
738 /* set the parity, stop bits and data size */
739 UART_PUT_MR(port
, mode
);
741 /* set the baud rate */
742 UART_PUT_BRGR(port
, quot
);
743 UART_PUT_CR(port
, ATMEL_US_RSTSTA
| ATMEL_US_RSTRX
);
744 UART_PUT_CR(port
, ATMEL_US_TXEN
| ATMEL_US_RXEN
);
746 /* restore interrupts */
747 UART_PUT_IER(port
, imr
);
749 /* CTS flow-control and modem-status interrupts */
750 if (UART_ENABLE_MS(port
, termios
->c_cflag
))
751 port
->ops
->enable_ms(port
);
753 spin_unlock_irqrestore(&port
->lock
, flags
);
757 * Return string describing the specified port
759 static const char *atmel_type(struct uart_port
*port
)
761 return (port
->type
== PORT_ATMEL
) ? "ATMEL_SERIAL" : NULL
;
765 * Release the memory region(s) being used by 'port'.
767 static void atmel_release_port(struct uart_port
*port
)
769 struct platform_device
*pdev
= to_platform_device(port
->dev
);
770 int size
= pdev
->resource
[0].end
- pdev
->resource
[0].start
+ 1;
772 release_mem_region(port
->mapbase
, size
);
774 if (port
->flags
& UPF_IOREMAP
) {
775 iounmap(port
->membase
);
776 port
->membase
= NULL
;
781 * Request the memory region(s) being used by 'port'.
783 static int atmel_request_port(struct uart_port
*port
)
785 struct platform_device
*pdev
= to_platform_device(port
->dev
);
786 int size
= pdev
->resource
[0].end
- pdev
->resource
[0].start
+ 1;
788 if (!request_mem_region(port
->mapbase
, size
, "atmel_serial"))
791 if (port
->flags
& UPF_IOREMAP
) {
792 port
->membase
= ioremap(port
->mapbase
, size
);
793 if (port
->membase
== NULL
) {
794 release_mem_region(port
->mapbase
, size
);
803 * Configure/autoconfigure the port.
805 static void atmel_config_port(struct uart_port
*port
, int flags
)
807 if (flags
& UART_CONFIG_TYPE
) {
808 port
->type
= PORT_ATMEL
;
809 atmel_request_port(port
);
814 * Verify the new serial_struct (for TIOCSSERIAL).
816 static int atmel_verify_port(struct uart_port
*port
, struct serial_struct
*ser
)
819 if (ser
->type
!= PORT_UNKNOWN
&& ser
->type
!= PORT_ATMEL
)
821 if (port
->irq
!= ser
->irq
)
823 if (ser
->io_type
!= SERIAL_IO_MEM
)
825 if (port
->uartclk
/ 16 != ser
->baud_base
)
827 if ((void *)port
->mapbase
!= ser
->iomem_base
)
829 if (port
->iobase
!= ser
->port
)
836 static struct uart_ops atmel_pops
= {
837 .tx_empty
= atmel_tx_empty
,
838 .set_mctrl
= atmel_set_mctrl
,
839 .get_mctrl
= atmel_get_mctrl
,
840 .stop_tx
= atmel_stop_tx
,
841 .start_tx
= atmel_start_tx
,
842 .stop_rx
= atmel_stop_rx
,
843 .enable_ms
= atmel_enable_ms
,
844 .break_ctl
= atmel_break_ctl
,
845 .startup
= atmel_startup
,
846 .shutdown
= atmel_shutdown
,
847 .set_termios
= atmel_set_termios
,
849 .release_port
= atmel_release_port
,
850 .request_port
= atmel_request_port
,
851 .config_port
= atmel_config_port
,
852 .verify_port
= atmel_verify_port
,
853 .pm
= atmel_serial_pm
,
857 * Configure the port from the platform device resource info.
859 static void __devinit
atmel_init_port(struct atmel_uart_port
*atmel_port
,
860 struct platform_device
*pdev
)
862 struct uart_port
*port
= &atmel_port
->uart
;
863 struct atmel_uart_data
*data
= pdev
->dev
.platform_data
;
865 port
->iotype
= UPIO_MEM
;
866 port
->flags
= UPF_BOOT_AUTOCONF
;
867 port
->ops
= &atmel_pops
;
869 port
->line
= pdev
->id
;
870 port
->dev
= &pdev
->dev
;
872 port
->mapbase
= pdev
->resource
[0].start
;
873 port
->irq
= pdev
->resource
[1].start
;
875 tasklet_init(&atmel_port
->tasklet
, atmel_tasklet_func
,
876 (unsigned long)port
);
878 memset(&atmel_port
->rx_ring
, 0, sizeof(atmel_port
->rx_ring
));
881 /* Already mapped by setup code */
882 port
->membase
= data
->regs
;
884 port
->flags
|= UPF_IOREMAP
;
885 port
->membase
= NULL
;
888 /* for console, the clock could already be configured */
889 if (!atmel_port
->clk
) {
890 atmel_port
->clk
= clk_get(&pdev
->dev
, "usart");
891 clk_enable(atmel_port
->clk
);
892 port
->uartclk
= clk_get_rate(atmel_port
->clk
);
897 * Register board-specific modem-control line handlers.
899 void __init
atmel_register_uart_fns(struct atmel_port_fns
*fns
)
902 atmel_pops
.enable_ms
= fns
->enable_ms
;
904 atmel_pops
.get_mctrl
= fns
->get_mctrl
;
906 atmel_pops
.set_mctrl
= fns
->set_mctrl
;
907 atmel_open_hook
= fns
->open
;
908 atmel_close_hook
= fns
->close
;
909 atmel_pops
.pm
= fns
->pm
;
910 atmel_pops
.set_wake
= fns
->set_wake
;
913 #ifdef CONFIG_SERIAL_ATMEL_CONSOLE
914 static void atmel_console_putchar(struct uart_port
*port
, int ch
)
916 while (!(UART_GET_CSR(port
) & ATMEL_US_TXRDY
))
918 UART_PUT_CHAR(port
, ch
);
922 * Interrupts are disabled on entering
924 static void atmel_console_write(struct console
*co
, const char *s
, u_int count
)
926 struct uart_port
*port
= &atmel_ports
[co
->index
].uart
;
927 unsigned int status
, imr
;
930 * First, save IMR and then disable interrupts
932 imr
= UART_GET_IMR(port
);
933 UART_PUT_IDR(port
, ATMEL_US_RXRDY
| ATMEL_US_TXRDY
);
935 uart_console_write(port
, s
, count
, atmel_console_putchar
);
938 * Finally, wait for transmitter to become empty
942 status
= UART_GET_CSR(port
);
943 } while (!(status
& ATMEL_US_TXRDY
));
944 /* set interrupts back the way they were */
945 UART_PUT_IER(port
, imr
);
949 * If the port was already initialised (eg, by a boot loader),
950 * try to determine the current setup.
952 static void __init
atmel_console_get_options(struct uart_port
*port
, int *baud
,
953 int *parity
, int *bits
)
955 unsigned int mr
, quot
;
958 * If the baud rate generator isn't running, the port wasn't
959 * initialized by the boot loader.
961 quot
= UART_GET_BRGR(port
);
965 mr
= UART_GET_MR(port
) & ATMEL_US_CHRL
;
966 if (mr
== ATMEL_US_CHRL_8
)
971 mr
= UART_GET_MR(port
) & ATMEL_US_PAR
;
972 if (mr
== ATMEL_US_PAR_EVEN
)
974 else if (mr
== ATMEL_US_PAR_ODD
)
978 * The serial core only rounds down when matching this to a
979 * supported baud rate. Make sure we don't end up slightly
980 * lower than one of those, as it would make us fall through
981 * to a much lower baud rate than we really want.
983 *baud
= port
->uartclk
/ (16 * (quot
- 1));
986 static int __init
atmel_console_setup(struct console
*co
, char *options
)
988 struct uart_port
*port
= &atmel_ports
[co
->index
].uart
;
994 if (port
->membase
== NULL
) {
995 /* Port not initialized yet - delay setup */
999 UART_PUT_IDR(port
, -1);
1000 UART_PUT_CR(port
, ATMEL_US_RSTSTA
| ATMEL_US_RSTRX
);
1001 UART_PUT_CR(port
, ATMEL_US_TXEN
| ATMEL_US_RXEN
);
1004 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
1006 atmel_console_get_options(port
, &baud
, &parity
, &bits
);
1008 return uart_set_options(port
, co
, baud
, parity
, bits
, flow
);
1011 static struct uart_driver atmel_uart
;
1013 static struct console atmel_console
= {
1014 .name
= ATMEL_DEVICENAME
,
1015 .write
= atmel_console_write
,
1016 .device
= uart_console_device
,
1017 .setup
= atmel_console_setup
,
1018 .flags
= CON_PRINTBUFFER
,
1020 .data
= &atmel_uart
,
1023 #define ATMEL_CONSOLE_DEVICE &atmel_console
1026 * Early console initialization (before VM subsystem initialized).
1028 static int __init
atmel_console_init(void)
1030 if (atmel_default_console_device
) {
1031 add_preferred_console(ATMEL_DEVICENAME
,
1032 atmel_default_console_device
->id
, NULL
);
1033 atmel_init_port(&atmel_ports
[atmel_default_console_device
->id
],
1034 atmel_default_console_device
);
1035 register_console(&atmel_console
);
1041 console_initcall(atmel_console_init
);
1044 * Late console initialization.
1046 static int __init
atmel_late_console_init(void)
1048 if (atmel_default_console_device
1049 && !(atmel_console
.flags
& CON_ENABLED
))
1050 register_console(&atmel_console
);
1055 core_initcall(atmel_late_console_init
);
1057 static inline bool atmel_is_console_port(struct uart_port
*port
)
1059 return port
->cons
&& port
->cons
->index
== port
->line
;
1063 #define ATMEL_CONSOLE_DEVICE NULL
1065 static inline bool atmel_is_console_port(struct uart_port
*port
)
1071 static struct uart_driver atmel_uart
= {
1072 .owner
= THIS_MODULE
,
1073 .driver_name
= "atmel_serial",
1074 .dev_name
= ATMEL_DEVICENAME
,
1075 .major
= SERIAL_ATMEL_MAJOR
,
1076 .minor
= MINOR_START
,
1077 .nr
= ATMEL_MAX_UART
,
1078 .cons
= ATMEL_CONSOLE_DEVICE
,
1082 static int atmel_serial_suspend(struct platform_device
*pdev
,
1085 struct uart_port
*port
= platform_get_drvdata(pdev
);
1086 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
1088 if (device_may_wakeup(&pdev
->dev
)
1089 && !at91_suspend_entering_slow_clock())
1090 enable_irq_wake(port
->irq
);
1092 uart_suspend_port(&atmel_uart
, port
);
1093 atmel_port
->suspended
= 1;
1099 static int atmel_serial_resume(struct platform_device
*pdev
)
1101 struct uart_port
*port
= platform_get_drvdata(pdev
);
1102 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
1104 if (atmel_port
->suspended
) {
1105 uart_resume_port(&atmel_uart
, port
);
1106 atmel_port
->suspended
= 0;
1108 disable_irq_wake(port
->irq
);
1113 #define atmel_serial_suspend NULL
1114 #define atmel_serial_resume NULL
1117 static int __devinit
atmel_serial_probe(struct platform_device
*pdev
)
1119 struct atmel_uart_port
*port
;
1123 BUILD_BUG_ON(!is_power_of_2(ATMEL_SERIAL_RINGSIZE
));
1125 port
= &atmel_ports
[pdev
->id
];
1126 atmel_init_port(port
, pdev
);
1129 data
= kmalloc(ATMEL_SERIAL_RINGSIZE
, GFP_KERNEL
);
1131 goto err_alloc_ring
;
1132 port
->rx_ring
.buf
= data
;
1134 ret
= uart_add_one_port(&atmel_uart
, &port
->uart
);
1138 device_init_wakeup(&pdev
->dev
, 1);
1139 platform_set_drvdata(pdev
, port
);
1144 kfree(port
->rx_ring
.buf
);
1145 port
->rx_ring
.buf
= NULL
;
1147 if (!atmel_is_console_port(&port
->uart
)) {
1148 clk_disable(port
->clk
);
1156 static int __devexit
atmel_serial_remove(struct platform_device
*pdev
)
1158 struct uart_port
*port
= platform_get_drvdata(pdev
);
1159 struct atmel_uart_port
*atmel_port
= (struct atmel_uart_port
*)port
;
1162 device_init_wakeup(&pdev
->dev
, 0);
1163 platform_set_drvdata(pdev
, NULL
);
1165 ret
= uart_remove_one_port(&atmel_uart
, port
);
1167 tasklet_kill(&atmel_port
->tasklet
);
1168 kfree(atmel_port
->rx_ring
.buf
);
1170 /* "port" is allocated statically, so we shouldn't free it */
1172 clk_disable(atmel_port
->clk
);
1173 clk_put(atmel_port
->clk
);
1178 static struct platform_driver atmel_serial_driver
= {
1179 .probe
= atmel_serial_probe
,
1180 .remove
= __devexit_p(atmel_serial_remove
),
1181 .suspend
= atmel_serial_suspend
,
1182 .resume
= atmel_serial_resume
,
1184 .name
= "atmel_usart",
1185 .owner
= THIS_MODULE
,
1189 static int __init
atmel_serial_init(void)
1193 ret
= uart_register_driver(&atmel_uart
);
1197 ret
= platform_driver_register(&atmel_serial_driver
);
1199 uart_unregister_driver(&atmel_uart
);
1204 static void __exit
atmel_serial_exit(void)
1206 platform_driver_unregister(&atmel_serial_driver
);
1207 uart_unregister_driver(&atmel_uart
);
1210 module_init(atmel_serial_init
);
1211 module_exit(atmel_serial_exit
);
1213 MODULE_AUTHOR("Rick Bronson");
1214 MODULE_DESCRIPTION("Atmel AT91 / AT32 serial port driver");
1215 MODULE_LICENSE("GPL");