2 * Driver for Atmel AT91 / AT32 Serial ports
3 * Copyright (C) 2003 Rick Bronson
5 * Based on drivers/char/serial_sa1100.c, by Deep Blue Solutions Ltd.
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
8 * DMA support added by Chip Coldwell.
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/dma-mapping.h>
37 #include <linux/atmel_pdc.h>
38 #include <linux/atmel_serial.h>
39 #include <linux/uaccess.h>
42 #include <asm/ioctls.h>
44 #include <asm/mach/serial_at91.h>
45 #include <mach/board.h>
49 #include <mach/gpio.h>
52 #define PDC_BUFFER_SIZE 512
53 /* Revisit: We should calculate this based on the actual port settings */
54 #define PDC_RX_TIMEOUT (3 * 10) /* 3 bytes */
56 #if defined(CONFIG_SERIAL_ATMEL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
60 #include <linux/serial_core.h>
62 static void atmel_start_rx(struct uart_port
*port
);
63 static void atmel_stop_rx(struct uart_port
*port
);
65 #ifdef CONFIG_SERIAL_ATMEL_TTYAT
67 /* Use device name ttyAT, major 204 and minor 154-169. This is necessary if we
68 * should coexist with the 8250 driver, such as if we have an external 16C550
70 #define SERIAL_ATMEL_MAJOR 204
71 #define MINOR_START 154
72 #define ATMEL_DEVICENAME "ttyAT"
76 /* Use device name ttyS, major 4, minor 64-68. This is the usual serial port
77 * name, but it is legally reserved for the 8250 driver. */
78 #define SERIAL_ATMEL_MAJOR TTY_MAJOR
79 #define MINOR_START 64
80 #define ATMEL_DEVICENAME "ttyS"
84 #define ATMEL_ISR_PASS_LIMIT 256
86 /* UART registers. CR is write-only, hence no GET macro */
87 #define UART_PUT_CR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_CR)
88 #define UART_GET_MR(port) __raw_readl((port)->membase + ATMEL_US_MR)
89 #define UART_PUT_MR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_MR)
90 #define UART_PUT_IER(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IER)
91 #define UART_PUT_IDR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IDR)
92 #define UART_GET_IMR(port) __raw_readl((port)->membase + ATMEL_US_IMR)
93 #define UART_GET_CSR(port) __raw_readl((port)->membase + ATMEL_US_CSR)
94 #define UART_GET_CHAR(port) __raw_readl((port)->membase + ATMEL_US_RHR)
95 #define UART_PUT_CHAR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_THR)
96 #define UART_GET_BRGR(port) __raw_readl((port)->membase + ATMEL_US_BRGR)
97 #define UART_PUT_BRGR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_BRGR)
98 #define UART_PUT_RTOR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_RTOR)
99 #define UART_PUT_TTGR(port, v) __raw_writel(v, (port)->membase + ATMEL_US_TTGR)
102 #define UART_PUT_PTCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
103 #define UART_GET_PTSR(port) __raw_readl((port)->membase + ATMEL_PDC_PTSR)
105 #define UART_PUT_RPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RPR)
106 #define UART_GET_RPR(port) __raw_readl((port)->membase + ATMEL_PDC_RPR)
107 #define UART_PUT_RCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RCR)
108 #define UART_PUT_RNPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNPR)
109 #define UART_PUT_RNCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNCR)
111 #define UART_PUT_TPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TPR)
112 #define UART_PUT_TCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TCR)
113 #define UART_GET_TCR(port) __raw_readl((port)->membase + ATMEL_PDC_TCR)
115 static int (*atmel_open_hook
)(struct uart_port
*);
116 static void (*atmel_close_hook
)(struct uart_port
*);
118 struct atmel_dma_buffer
{
121 unsigned int dma_size
;
125 struct atmel_uart_char
{
130 #define ATMEL_SERIAL_RINGSIZE 1024
133 * We wrap our port structure around the generic uart_port.
135 struct atmel_uart_port
{
136 struct uart_port uart
; /* uart */
137 struct clk
*clk
; /* uart clock */
138 int may_wakeup
; /* cached value of device_may_wakeup for times we need to disable it */
139 u32 backup_imr
; /* IMR saved during suspend */
140 int break_active
; /* break being received */
142 short use_dma_rx
; /* enable PDC receiver */
143 short pdc_rx_idx
; /* current PDC RX buffer */
144 struct atmel_dma_buffer pdc_rx
[2]; /* PDC receier */
146 short use_dma_tx
; /* enable PDC transmitter */
147 struct atmel_dma_buffer pdc_tx
; /* PDC transmitter */
149 struct tasklet_struct tasklet
;
150 unsigned int irq_status
;
151 unsigned int irq_status_prev
;
153 struct circ_buf rx_ring
;
155 struct serial_rs485 rs485
; /* rs485 settings */
156 unsigned int tx_done_mask
;
159 static struct atmel_uart_port atmel_ports
[ATMEL_MAX_UART
];
162 static struct console atmel_console
;
165 static inline struct atmel_uart_port
*
166 to_atmel_uart_port(struct uart_port
*uart
)
168 return container_of(uart
, struct atmel_uart_port
, uart
);
171 #ifdef CONFIG_SERIAL_ATMEL_PDC
172 static bool atmel_use_dma_rx(struct uart_port
*port
)
174 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
176 return atmel_port
->use_dma_rx
;
179 static bool atmel_use_dma_tx(struct uart_port
*port
)
181 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
183 return atmel_port
->use_dma_tx
;
186 static bool atmel_use_dma_rx(struct uart_port
*port
)
191 static bool atmel_use_dma_tx(struct uart_port
*port
)
197 /* Enable or disable the rs485 support */
198 void atmel_config_rs485(struct uart_port
*port
, struct serial_rs485
*rs485conf
)
200 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
203 spin_lock(&port
->lock
);
205 /* Disable interrupts */
206 UART_PUT_IDR(port
, atmel_port
->tx_done_mask
);
208 mode
= UART_GET_MR(port
);
210 /* Resetting serial mode to RS232 (0x0) */
211 mode
&= ~ATMEL_US_USMODE
;
213 atmel_port
->rs485
= *rs485conf
;
215 if (rs485conf
->flags
& SER_RS485_ENABLED
) {
216 dev_dbg(port
->dev
, "Setting UART to RS485\n");
217 atmel_port
->tx_done_mask
= ATMEL_US_TXEMPTY
;
218 if (rs485conf
->flags
& SER_RS485_RTS_AFTER_SEND
)
219 UART_PUT_TTGR(port
, rs485conf
->delay_rts_after_send
);
220 mode
|= ATMEL_US_USMODE_RS485
;
222 dev_dbg(port
->dev
, "Setting UART to RS232\n");
223 if (atmel_use_dma_tx(port
))
224 atmel_port
->tx_done_mask
= ATMEL_US_ENDTX
|
227 atmel_port
->tx_done_mask
= ATMEL_US_TXRDY
;
229 UART_PUT_MR(port
, mode
);
231 /* Enable interrupts */
232 UART_PUT_IER(port
, atmel_port
->tx_done_mask
);
234 spin_unlock(&port
->lock
);
239 * Return TIOCSER_TEMT when transmitter FIFO and Shift register is empty.
241 static u_int
atmel_tx_empty(struct uart_port
*port
)
243 return (UART_GET_CSR(port
) & ATMEL_US_TXEMPTY
) ? TIOCSER_TEMT
: 0;
247 * Set state of the modem control output lines
249 static void atmel_set_mctrl(struct uart_port
*port
, u_int mctrl
)
251 unsigned int control
= 0;
253 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
255 #ifdef CONFIG_ARCH_AT91RM9200
256 if (cpu_is_at91rm9200()) {
258 * AT91RM9200 Errata #39: RTS0 is not internally connected
259 * to PA21. We need to drive the pin manually.
261 if (port
->mapbase
== AT91RM9200_BASE_US0
) {
262 if (mctrl
& TIOCM_RTS
)
263 at91_set_gpio_value(AT91_PIN_PA21
, 0);
265 at91_set_gpio_value(AT91_PIN_PA21
, 1);
270 if (mctrl
& TIOCM_RTS
)
271 control
|= ATMEL_US_RTSEN
;
273 control
|= ATMEL_US_RTSDIS
;
275 if (mctrl
& TIOCM_DTR
)
276 control
|= ATMEL_US_DTREN
;
278 control
|= ATMEL_US_DTRDIS
;
280 UART_PUT_CR(port
, control
);
282 /* Local loopback mode? */
283 mode
= UART_GET_MR(port
) & ~ATMEL_US_CHMODE
;
284 if (mctrl
& TIOCM_LOOP
)
285 mode
|= ATMEL_US_CHMODE_LOC_LOOP
;
287 mode
|= ATMEL_US_CHMODE_NORMAL
;
289 /* Resetting serial mode to RS232 (0x0) */
290 mode
&= ~ATMEL_US_USMODE
;
292 if (atmel_port
->rs485
.flags
& SER_RS485_ENABLED
) {
293 dev_dbg(port
->dev
, "Setting UART to RS485\n");
294 if (atmel_port
->rs485
.flags
& SER_RS485_RTS_AFTER_SEND
)
296 atmel_port
->rs485
.delay_rts_after_send
);
297 mode
|= ATMEL_US_USMODE_RS485
;
299 dev_dbg(port
->dev
, "Setting UART to RS232\n");
301 UART_PUT_MR(port
, mode
);
305 * Get state of the modem control input lines
307 static u_int
atmel_get_mctrl(struct uart_port
*port
)
309 unsigned int status
, ret
= 0;
311 status
= UART_GET_CSR(port
);
314 * The control signals are active low.
316 if (!(status
& ATMEL_US_DCD
))
318 if (!(status
& ATMEL_US_CTS
))
320 if (!(status
& ATMEL_US_DSR
))
322 if (!(status
& ATMEL_US_RI
))
331 static void atmel_stop_tx(struct uart_port
*port
)
333 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
335 if (atmel_use_dma_tx(port
)) {
336 /* disable PDC transmit */
337 UART_PUT_PTCR(port
, ATMEL_PDC_TXTDIS
);
339 /* Disable interrupts */
340 UART_PUT_IDR(port
, atmel_port
->tx_done_mask
);
342 if (atmel_port
->rs485
.flags
& SER_RS485_ENABLED
)
343 atmel_start_rx(port
);
347 * Start transmitting.
349 static void atmel_start_tx(struct uart_port
*port
)
351 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
353 if (atmel_use_dma_tx(port
)) {
354 if (UART_GET_PTSR(port
) & ATMEL_PDC_TXTEN
)
355 /* The transmitter is already running. Yes, we
359 if (atmel_port
->rs485
.flags
& SER_RS485_ENABLED
)
362 /* re-enable PDC transmit */
363 UART_PUT_PTCR(port
, ATMEL_PDC_TXTEN
);
365 /* Enable interrupts */
366 UART_PUT_IER(port
, atmel_port
->tx_done_mask
);
370 * start receiving - port is in process of being opened.
372 static void atmel_start_rx(struct uart_port
*port
)
374 UART_PUT_CR(port
, ATMEL_US_RSTSTA
); /* reset status and receiver */
376 if (atmel_use_dma_rx(port
)) {
377 /* enable PDC controller */
378 UART_PUT_IER(port
, ATMEL_US_ENDRX
| ATMEL_US_TIMEOUT
|
379 port
->read_status_mask
);
380 UART_PUT_PTCR(port
, ATMEL_PDC_RXTEN
);
382 UART_PUT_IER(port
, ATMEL_US_RXRDY
);
387 * Stop receiving - port is in process of being closed.
389 static void atmel_stop_rx(struct uart_port
*port
)
391 if (atmel_use_dma_rx(port
)) {
392 /* disable PDC receive */
393 UART_PUT_PTCR(port
, ATMEL_PDC_RXTDIS
);
394 UART_PUT_IDR(port
, ATMEL_US_ENDRX
| ATMEL_US_TIMEOUT
|
395 port
->read_status_mask
);
397 UART_PUT_IDR(port
, ATMEL_US_RXRDY
);
402 * Enable modem status interrupts
404 static void atmel_enable_ms(struct uart_port
*port
)
406 UART_PUT_IER(port
, ATMEL_US_RIIC
| ATMEL_US_DSRIC
407 | ATMEL_US_DCDIC
| ATMEL_US_CTSIC
);
411 * Control the transmission of a break signal
413 static void atmel_break_ctl(struct uart_port
*port
, int break_state
)
415 if (break_state
!= 0)
416 UART_PUT_CR(port
, ATMEL_US_STTBRK
); /* start break */
418 UART_PUT_CR(port
, ATMEL_US_STPBRK
); /* stop break */
422 * Stores the incoming character in the ring buffer
425 atmel_buffer_rx_char(struct uart_port
*port
, unsigned int status
,
428 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
429 struct circ_buf
*ring
= &atmel_port
->rx_ring
;
430 struct atmel_uart_char
*c
;
432 if (!CIRC_SPACE(ring
->head
, ring
->tail
, ATMEL_SERIAL_RINGSIZE
))
433 /* Buffer overflow, ignore char */
436 c
= &((struct atmel_uart_char
*)ring
->buf
)[ring
->head
];
440 /* Make sure the character is stored before we update head. */
443 ring
->head
= (ring
->head
+ 1) & (ATMEL_SERIAL_RINGSIZE
- 1);
447 * Deal with parity, framing and overrun errors.
449 static void atmel_pdc_rxerr(struct uart_port
*port
, unsigned int status
)
452 UART_PUT_CR(port
, ATMEL_US_RSTSTA
);
454 if (status
& ATMEL_US_RXBRK
) {
455 /* ignore side-effect */
456 status
&= ~(ATMEL_US_PARE
| ATMEL_US_FRAME
);
459 if (status
& ATMEL_US_PARE
)
460 port
->icount
.parity
++;
461 if (status
& ATMEL_US_FRAME
)
462 port
->icount
.frame
++;
463 if (status
& ATMEL_US_OVRE
)
464 port
->icount
.overrun
++;
468 * Characters received (called from interrupt handler)
470 static void atmel_rx_chars(struct uart_port
*port
)
472 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
473 unsigned int status
, ch
;
475 status
= UART_GET_CSR(port
);
476 while (status
& ATMEL_US_RXRDY
) {
477 ch
= UART_GET_CHAR(port
);
480 * note that the error handling code is
481 * out of the main execution path
483 if (unlikely(status
& (ATMEL_US_PARE
| ATMEL_US_FRAME
484 | ATMEL_US_OVRE
| ATMEL_US_RXBRK
)
485 || atmel_port
->break_active
)) {
488 UART_PUT_CR(port
, ATMEL_US_RSTSTA
);
490 if (status
& ATMEL_US_RXBRK
491 && !atmel_port
->break_active
) {
492 atmel_port
->break_active
= 1;
493 UART_PUT_IER(port
, ATMEL_US_RXBRK
);
496 * This is either the end-of-break
497 * condition or we've received at
498 * least one character without RXBRK
499 * being set. In both cases, the next
500 * RXBRK will indicate start-of-break.
502 UART_PUT_IDR(port
, ATMEL_US_RXBRK
);
503 status
&= ~ATMEL_US_RXBRK
;
504 atmel_port
->break_active
= 0;
508 atmel_buffer_rx_char(port
, status
, ch
);
509 status
= UART_GET_CSR(port
);
512 tasklet_schedule(&atmel_port
->tasklet
);
516 * Transmit characters (called from tasklet with TXRDY interrupt
519 static void atmel_tx_chars(struct uart_port
*port
)
521 struct circ_buf
*xmit
= &port
->state
->xmit
;
522 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
524 if (port
->x_char
&& UART_GET_CSR(port
) & atmel_port
->tx_done_mask
) {
525 UART_PUT_CHAR(port
, port
->x_char
);
529 if (uart_circ_empty(xmit
) || uart_tx_stopped(port
))
532 while (UART_GET_CSR(port
) & atmel_port
->tx_done_mask
) {
533 UART_PUT_CHAR(port
, xmit
->buf
[xmit
->tail
]);
534 xmit
->tail
= (xmit
->tail
+ 1) & (UART_XMIT_SIZE
- 1);
536 if (uart_circ_empty(xmit
))
540 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
541 uart_write_wakeup(port
);
543 if (!uart_circ_empty(xmit
))
544 /* Enable interrupts */
545 UART_PUT_IER(port
, atmel_port
->tx_done_mask
);
549 * receive interrupt handler.
552 atmel_handle_receive(struct uart_port
*port
, unsigned int pending
)
554 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
556 if (atmel_use_dma_rx(port
)) {
558 * PDC receive. Just schedule the tasklet and let it
559 * figure out the details.
561 * TODO: We're not handling error flags correctly at
564 if (pending
& (ATMEL_US_ENDRX
| ATMEL_US_TIMEOUT
)) {
565 UART_PUT_IDR(port
, (ATMEL_US_ENDRX
566 | ATMEL_US_TIMEOUT
));
567 tasklet_schedule(&atmel_port
->tasklet
);
570 if (pending
& (ATMEL_US_RXBRK
| ATMEL_US_OVRE
|
571 ATMEL_US_FRAME
| ATMEL_US_PARE
))
572 atmel_pdc_rxerr(port
, pending
);
575 /* Interrupt receive */
576 if (pending
& ATMEL_US_RXRDY
)
577 atmel_rx_chars(port
);
578 else if (pending
& ATMEL_US_RXBRK
) {
580 * End of break detected. If it came along with a
581 * character, atmel_rx_chars will handle it.
583 UART_PUT_CR(port
, ATMEL_US_RSTSTA
);
584 UART_PUT_IDR(port
, ATMEL_US_RXBRK
);
585 atmel_port
->break_active
= 0;
590 * transmit interrupt handler. (Transmit is IRQF_NODELAY safe)
593 atmel_handle_transmit(struct uart_port
*port
, unsigned int pending
)
595 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
597 if (pending
& atmel_port
->tx_done_mask
) {
598 /* Either PDC or interrupt transmission */
599 UART_PUT_IDR(port
, atmel_port
->tx_done_mask
);
600 tasklet_schedule(&atmel_port
->tasklet
);
605 * status flags interrupt handler.
608 atmel_handle_status(struct uart_port
*port
, unsigned int pending
,
611 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
613 if (pending
& (ATMEL_US_RIIC
| ATMEL_US_DSRIC
| ATMEL_US_DCDIC
615 atmel_port
->irq_status
= status
;
616 tasklet_schedule(&atmel_port
->tasklet
);
623 static irqreturn_t
atmel_interrupt(int irq
, void *dev_id
)
625 struct uart_port
*port
= dev_id
;
626 unsigned int status
, pending
, pass_counter
= 0;
629 status
= UART_GET_CSR(port
);
630 pending
= status
& UART_GET_IMR(port
);
634 atmel_handle_receive(port
, pending
);
635 atmel_handle_status(port
, pending
, status
);
636 atmel_handle_transmit(port
, pending
);
637 } while (pass_counter
++ < ATMEL_ISR_PASS_LIMIT
);
639 return pass_counter
? IRQ_HANDLED
: IRQ_NONE
;
643 * Called from tasklet with ENDTX and TXBUFE interrupts disabled.
645 static void atmel_tx_dma(struct uart_port
*port
)
647 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
648 struct circ_buf
*xmit
= &port
->state
->xmit
;
649 struct atmel_dma_buffer
*pdc
= &atmel_port
->pdc_tx
;
652 /* nothing left to transmit? */
653 if (UART_GET_TCR(port
))
656 xmit
->tail
+= pdc
->ofs
;
657 xmit
->tail
&= UART_XMIT_SIZE
- 1;
659 port
->icount
.tx
+= pdc
->ofs
;
662 /* more to transmit - setup next transfer */
664 /* disable PDC transmit */
665 UART_PUT_PTCR(port
, ATMEL_PDC_TXTDIS
);
667 if (!uart_circ_empty(xmit
) && !uart_tx_stopped(port
)) {
668 dma_sync_single_for_device(port
->dev
,
673 count
= CIRC_CNT_TO_END(xmit
->head
, xmit
->tail
, UART_XMIT_SIZE
);
676 UART_PUT_TPR(port
, pdc
->dma_addr
+ xmit
->tail
);
677 UART_PUT_TCR(port
, count
);
678 /* re-enable PDC transmit */
679 UART_PUT_PTCR(port
, ATMEL_PDC_TXTEN
);
680 /* Enable interrupts */
681 UART_PUT_IER(port
, atmel_port
->tx_done_mask
);
683 if (atmel_port
->rs485
.flags
& SER_RS485_ENABLED
) {
684 /* DMA done, stop TX, start RX for RS485 */
685 atmel_start_rx(port
);
689 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
690 uart_write_wakeup(port
);
693 static void atmel_rx_from_ring(struct uart_port
*port
)
695 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
696 struct circ_buf
*ring
= &atmel_port
->rx_ring
;
700 while (ring
->head
!= ring
->tail
) {
701 struct atmel_uart_char c
;
703 /* Make sure c is loaded after head. */
706 c
= ((struct atmel_uart_char
*)ring
->buf
)[ring
->tail
];
708 ring
->tail
= (ring
->tail
+ 1) & (ATMEL_SERIAL_RINGSIZE
- 1);
715 * note that the error handling code is
716 * out of the main execution path
718 if (unlikely(status
& (ATMEL_US_PARE
| ATMEL_US_FRAME
719 | ATMEL_US_OVRE
| ATMEL_US_RXBRK
))) {
720 if (status
& ATMEL_US_RXBRK
) {
721 /* ignore side-effect */
722 status
&= ~(ATMEL_US_PARE
| ATMEL_US_FRAME
);
725 if (uart_handle_break(port
))
728 if (status
& ATMEL_US_PARE
)
729 port
->icount
.parity
++;
730 if (status
& ATMEL_US_FRAME
)
731 port
->icount
.frame
++;
732 if (status
& ATMEL_US_OVRE
)
733 port
->icount
.overrun
++;
735 status
&= port
->read_status_mask
;
737 if (status
& ATMEL_US_RXBRK
)
739 else if (status
& ATMEL_US_PARE
)
741 else if (status
& ATMEL_US_FRAME
)
746 if (uart_handle_sysrq_char(port
, c
.ch
))
749 uart_insert_char(port
, status
, ATMEL_US_OVRE
, c
.ch
, flg
);
753 * Drop the lock here since it might end up calling
754 * uart_start(), which takes the lock.
756 spin_unlock(&port
->lock
);
757 tty_flip_buffer_push(port
->state
->port
.tty
);
758 spin_lock(&port
->lock
);
761 static void atmel_rx_from_dma(struct uart_port
*port
)
763 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
764 struct tty_struct
*tty
= port
->state
->port
.tty
;
765 struct atmel_dma_buffer
*pdc
;
766 int rx_idx
= atmel_port
->pdc_rx_idx
;
772 /* Reset the UART timeout early so that we don't miss one */
773 UART_PUT_CR(port
, ATMEL_US_STTTO
);
775 pdc
= &atmel_port
->pdc_rx
[rx_idx
];
776 head
= UART_GET_RPR(port
) - pdc
->dma_addr
;
779 /* If the PDC has switched buffers, RPR won't contain
780 * any address within the current buffer. Since head
781 * is unsigned, we just need a one-way comparison to
784 * In this case, we just need to consume the entire
785 * buffer and resubmit it for DMA. This will clear the
786 * ENDRX bit as well, so that we can safely re-enable
787 * all interrupts below.
789 head
= min(head
, pdc
->dma_size
);
791 if (likely(head
!= tail
)) {
792 dma_sync_single_for_cpu(port
->dev
, pdc
->dma_addr
,
793 pdc
->dma_size
, DMA_FROM_DEVICE
);
796 * head will only wrap around when we recycle
797 * the DMA buffer, and when that happens, we
798 * explicitly set tail to 0. So head will
799 * always be greater than tail.
803 tty_insert_flip_string(tty
, pdc
->buf
+ pdc
->ofs
, count
);
805 dma_sync_single_for_device(port
->dev
, pdc
->dma_addr
,
806 pdc
->dma_size
, DMA_FROM_DEVICE
);
808 port
->icount
.rx
+= count
;
813 * If the current buffer is full, we need to check if
814 * the next one contains any additional data.
816 if (head
>= pdc
->dma_size
) {
818 UART_PUT_RNPR(port
, pdc
->dma_addr
);
819 UART_PUT_RNCR(port
, pdc
->dma_size
);
822 atmel_port
->pdc_rx_idx
= rx_idx
;
824 } while (head
>= pdc
->dma_size
);
827 * Drop the lock here since it might end up calling
828 * uart_start(), which takes the lock.
830 spin_unlock(&port
->lock
);
831 tty_flip_buffer_push(tty
);
832 spin_lock(&port
->lock
);
834 UART_PUT_IER(port
, ATMEL_US_ENDRX
| ATMEL_US_TIMEOUT
);
838 * tasklet handling tty stuff outside the interrupt handler.
840 static void atmel_tasklet_func(unsigned long data
)
842 struct uart_port
*port
= (struct uart_port
*)data
;
843 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
845 unsigned int status_change
;
847 /* The interrupt handler does not take the lock */
848 spin_lock(&port
->lock
);
850 if (atmel_use_dma_tx(port
))
853 atmel_tx_chars(port
);
855 status
= atmel_port
->irq_status
;
856 status_change
= status
^ atmel_port
->irq_status_prev
;
858 if (status_change
& (ATMEL_US_RI
| ATMEL_US_DSR
859 | ATMEL_US_DCD
| ATMEL_US_CTS
)) {
860 /* TODO: All reads to CSR will clear these interrupts! */
861 if (status_change
& ATMEL_US_RI
)
863 if (status_change
& ATMEL_US_DSR
)
865 if (status_change
& ATMEL_US_DCD
)
866 uart_handle_dcd_change(port
, !(status
& ATMEL_US_DCD
));
867 if (status_change
& ATMEL_US_CTS
)
868 uart_handle_cts_change(port
, !(status
& ATMEL_US_CTS
));
870 wake_up_interruptible(&port
->state
->port
.delta_msr_wait
);
872 atmel_port
->irq_status_prev
= status
;
875 if (atmel_use_dma_rx(port
))
876 atmel_rx_from_dma(port
);
878 atmel_rx_from_ring(port
);
880 spin_unlock(&port
->lock
);
884 * Perform initialization and enable port for reception
886 static int atmel_startup(struct uart_port
*port
)
888 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
889 struct tty_struct
*tty
= port
->state
->port
.tty
;
893 * Ensure that no interrupts are enabled otherwise when
894 * request_irq() is called we could get stuck trying to
895 * handle an unexpected interrupt
897 UART_PUT_IDR(port
, -1);
902 retval
= request_irq(port
->irq
, atmel_interrupt
, IRQF_SHARED
,
903 tty
? tty
->name
: "atmel_serial", port
);
905 printk("atmel_serial: atmel_startup - Can't get irq\n");
910 * Initialize DMA (if necessary)
912 if (atmel_use_dma_rx(port
)) {
915 for (i
= 0; i
< 2; i
++) {
916 struct atmel_dma_buffer
*pdc
= &atmel_port
->pdc_rx
[i
];
918 pdc
->buf
= kmalloc(PDC_BUFFER_SIZE
, GFP_KERNEL
);
919 if (pdc
->buf
== NULL
) {
921 dma_unmap_single(port
->dev
,
922 atmel_port
->pdc_rx
[0].dma_addr
,
925 kfree(atmel_port
->pdc_rx
[0].buf
);
927 free_irq(port
->irq
, port
);
930 pdc
->dma_addr
= dma_map_single(port
->dev
,
934 pdc
->dma_size
= PDC_BUFFER_SIZE
;
938 atmel_port
->pdc_rx_idx
= 0;
940 UART_PUT_RPR(port
, atmel_port
->pdc_rx
[0].dma_addr
);
941 UART_PUT_RCR(port
, PDC_BUFFER_SIZE
);
943 UART_PUT_RNPR(port
, atmel_port
->pdc_rx
[1].dma_addr
);
944 UART_PUT_RNCR(port
, PDC_BUFFER_SIZE
);
946 if (atmel_use_dma_tx(port
)) {
947 struct atmel_dma_buffer
*pdc
= &atmel_port
->pdc_tx
;
948 struct circ_buf
*xmit
= &port
->state
->xmit
;
950 pdc
->buf
= xmit
->buf
;
951 pdc
->dma_addr
= dma_map_single(port
->dev
,
955 pdc
->dma_size
= UART_XMIT_SIZE
;
960 * If there is a specific "open" function (to register
961 * control line interrupts)
963 if (atmel_open_hook
) {
964 retval
= atmel_open_hook(port
);
966 free_irq(port
->irq
, port
);
971 /* Save current CSR for comparison in atmel_tasklet_func() */
972 atmel_port
->irq_status_prev
= UART_GET_CSR(port
);
973 atmel_port
->irq_status
= atmel_port
->irq_status_prev
;
976 * Finally, enable the serial port
978 UART_PUT_CR(port
, ATMEL_US_RSTSTA
| ATMEL_US_RSTRX
);
979 /* enable xmit & rcvr */
980 UART_PUT_CR(port
, ATMEL_US_TXEN
| ATMEL_US_RXEN
);
982 if (atmel_use_dma_rx(port
)) {
983 /* set UART timeout */
984 UART_PUT_RTOR(port
, PDC_RX_TIMEOUT
);
985 UART_PUT_CR(port
, ATMEL_US_STTTO
);
987 UART_PUT_IER(port
, ATMEL_US_ENDRX
| ATMEL_US_TIMEOUT
);
988 /* enable PDC controller */
989 UART_PUT_PTCR(port
, ATMEL_PDC_RXTEN
);
991 /* enable receive only */
992 UART_PUT_IER(port
, ATMEL_US_RXRDY
);
1001 static void atmel_shutdown(struct uart_port
*port
)
1003 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1005 * Ensure everything is stopped.
1007 atmel_stop_rx(port
);
1008 atmel_stop_tx(port
);
1011 * Shut-down the DMA.
1013 if (atmel_use_dma_rx(port
)) {
1016 for (i
= 0; i
< 2; i
++) {
1017 struct atmel_dma_buffer
*pdc
= &atmel_port
->pdc_rx
[i
];
1019 dma_unmap_single(port
->dev
,
1026 if (atmel_use_dma_tx(port
)) {
1027 struct atmel_dma_buffer
*pdc
= &atmel_port
->pdc_tx
;
1029 dma_unmap_single(port
->dev
,
1036 * Disable all interrupts, port and break condition.
1038 UART_PUT_CR(port
, ATMEL_US_RSTSTA
);
1039 UART_PUT_IDR(port
, -1);
1042 * Free the interrupt
1044 free_irq(port
->irq
, port
);
1047 * If there is a specific "close" function (to unregister
1048 * control line interrupts)
1050 if (atmel_close_hook
)
1051 atmel_close_hook(port
);
1055 * Flush any TX data submitted for DMA. Called when the TX circular
1058 static void atmel_flush_buffer(struct uart_port
*port
)
1060 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1062 if (atmel_use_dma_tx(port
)) {
1063 UART_PUT_TCR(port
, 0);
1064 atmel_port
->pdc_tx
.ofs
= 0;
1069 * Power / Clock management.
1071 static void atmel_serial_pm(struct uart_port
*port
, unsigned int state
,
1072 unsigned int oldstate
)
1074 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1079 * Enable the peripheral clock for this serial port.
1080 * This is called on uart_open() or a resume event.
1082 clk_enable(atmel_port
->clk
);
1084 /* re-enable interrupts if we disabled some on suspend */
1085 UART_PUT_IER(port
, atmel_port
->backup_imr
);
1088 /* Back up the interrupt mask and disable all interrupts */
1089 atmel_port
->backup_imr
= UART_GET_IMR(port
);
1090 UART_PUT_IDR(port
, -1);
1093 * Disable the peripheral clock for this serial port.
1094 * This is called on uart_close() or a suspend event.
1096 clk_disable(atmel_port
->clk
);
1099 printk(KERN_ERR
"atmel_serial: unknown pm %d\n", state
);
1104 * Change the port parameters
1106 static void atmel_set_termios(struct uart_port
*port
, struct ktermios
*termios
,
1107 struct ktermios
*old
)
1109 unsigned long flags
;
1110 unsigned int mode
, imr
, quot
, baud
;
1111 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1113 /* Get current mode register */
1114 mode
= UART_GET_MR(port
) & ~(ATMEL_US_USCLKS
| ATMEL_US_CHRL
1115 | ATMEL_US_NBSTOP
| ATMEL_US_PAR
1118 baud
= uart_get_baud_rate(port
, termios
, old
, 0, port
->uartclk
/ 16);
1119 quot
= uart_get_divisor(port
, baud
);
1121 if (quot
> 65535) { /* BRGR is 16-bit, so switch to slower clock */
1123 mode
|= ATMEL_US_USCLKS_MCK_DIV8
;
1127 switch (termios
->c_cflag
& CSIZE
) {
1129 mode
|= ATMEL_US_CHRL_5
;
1132 mode
|= ATMEL_US_CHRL_6
;
1135 mode
|= ATMEL_US_CHRL_7
;
1138 mode
|= ATMEL_US_CHRL_8
;
1143 if (termios
->c_cflag
& CSTOPB
)
1144 mode
|= ATMEL_US_NBSTOP_2
;
1147 if (termios
->c_cflag
& PARENB
) {
1148 /* Mark or Space parity */
1149 if (termios
->c_cflag
& CMSPAR
) {
1150 if (termios
->c_cflag
& PARODD
)
1151 mode
|= ATMEL_US_PAR_MARK
;
1153 mode
|= ATMEL_US_PAR_SPACE
;
1154 } else if (termios
->c_cflag
& PARODD
)
1155 mode
|= ATMEL_US_PAR_ODD
;
1157 mode
|= ATMEL_US_PAR_EVEN
;
1159 mode
|= ATMEL_US_PAR_NONE
;
1161 /* hardware handshake (RTS/CTS) */
1162 if (termios
->c_cflag
& CRTSCTS
)
1163 mode
|= ATMEL_US_USMODE_HWHS
;
1165 mode
|= ATMEL_US_USMODE_NORMAL
;
1167 spin_lock_irqsave(&port
->lock
, flags
);
1169 port
->read_status_mask
= ATMEL_US_OVRE
;
1170 if (termios
->c_iflag
& INPCK
)
1171 port
->read_status_mask
|= (ATMEL_US_FRAME
| ATMEL_US_PARE
);
1172 if (termios
->c_iflag
& (BRKINT
| PARMRK
))
1173 port
->read_status_mask
|= ATMEL_US_RXBRK
;
1175 if (atmel_use_dma_rx(port
))
1176 /* need to enable error interrupts */
1177 UART_PUT_IER(port
, port
->read_status_mask
);
1180 * Characters to ignore
1182 port
->ignore_status_mask
= 0;
1183 if (termios
->c_iflag
& IGNPAR
)
1184 port
->ignore_status_mask
|= (ATMEL_US_FRAME
| ATMEL_US_PARE
);
1185 if (termios
->c_iflag
& IGNBRK
) {
1186 port
->ignore_status_mask
|= ATMEL_US_RXBRK
;
1188 * If we're ignoring parity and break indicators,
1189 * ignore overruns too (for real raw support).
1191 if (termios
->c_iflag
& IGNPAR
)
1192 port
->ignore_status_mask
|= ATMEL_US_OVRE
;
1194 /* TODO: Ignore all characters if CREAD is set.*/
1196 /* update the per-port timeout */
1197 uart_update_timeout(port
, termios
->c_cflag
, baud
);
1200 * save/disable interrupts. The tty layer will ensure that the
1201 * transmitter is empty if requested by the caller, so there's
1202 * no need to wait for it here.
1204 imr
= UART_GET_IMR(port
);
1205 UART_PUT_IDR(port
, -1);
1207 /* disable receiver and transmitter */
1208 UART_PUT_CR(port
, ATMEL_US_TXDIS
| ATMEL_US_RXDIS
);
1210 /* Resetting serial mode to RS232 (0x0) */
1211 mode
&= ~ATMEL_US_USMODE
;
1213 if (atmel_port
->rs485
.flags
& SER_RS485_ENABLED
) {
1214 dev_dbg(port
->dev
, "Setting UART to RS485\n");
1215 if (atmel_port
->rs485
.flags
& SER_RS485_RTS_AFTER_SEND
)
1217 atmel_port
->rs485
.delay_rts_after_send
);
1218 mode
|= ATMEL_US_USMODE_RS485
;
1220 dev_dbg(port
->dev
, "Setting UART to RS232\n");
1223 /* set the parity, stop bits and data size */
1224 UART_PUT_MR(port
, mode
);
1226 /* set the baud rate */
1227 UART_PUT_BRGR(port
, quot
);
1228 UART_PUT_CR(port
, ATMEL_US_RSTSTA
| ATMEL_US_RSTRX
);
1229 UART_PUT_CR(port
, ATMEL_US_TXEN
| ATMEL_US_RXEN
);
1231 /* restore interrupts */
1232 UART_PUT_IER(port
, imr
);
1234 /* CTS flow-control and modem-status interrupts */
1235 if (UART_ENABLE_MS(port
, termios
->c_cflag
))
1236 port
->ops
->enable_ms(port
);
1238 spin_unlock_irqrestore(&port
->lock
, flags
);
1241 static void atmel_set_ldisc(struct uart_port
*port
, int new)
1243 int line
= port
->line
;
1245 if (line
>= port
->state
->port
.tty
->driver
->num
)
1248 if (port
->state
->port
.tty
->ldisc
->ops
->num
== N_PPS
) {
1249 port
->flags
|= UPF_HARDPPS_CD
;
1250 atmel_enable_ms(port
);
1252 port
->flags
&= ~UPF_HARDPPS_CD
;
1257 * Return string describing the specified port
1259 static const char *atmel_type(struct uart_port
*port
)
1261 return (port
->type
== PORT_ATMEL
) ? "ATMEL_SERIAL" : NULL
;
1265 * Release the memory region(s) being used by 'port'.
1267 static void atmel_release_port(struct uart_port
*port
)
1269 struct platform_device
*pdev
= to_platform_device(port
->dev
);
1270 int size
= pdev
->resource
[0].end
- pdev
->resource
[0].start
+ 1;
1272 release_mem_region(port
->mapbase
, size
);
1274 if (port
->flags
& UPF_IOREMAP
) {
1275 iounmap(port
->membase
);
1276 port
->membase
= NULL
;
1281 * Request the memory region(s) being used by 'port'.
1283 static int atmel_request_port(struct uart_port
*port
)
1285 struct platform_device
*pdev
= to_platform_device(port
->dev
);
1286 int size
= pdev
->resource
[0].end
- pdev
->resource
[0].start
+ 1;
1288 if (!request_mem_region(port
->mapbase
, size
, "atmel_serial"))
1291 if (port
->flags
& UPF_IOREMAP
) {
1292 port
->membase
= ioremap(port
->mapbase
, size
);
1293 if (port
->membase
== NULL
) {
1294 release_mem_region(port
->mapbase
, size
);
1303 * Configure/autoconfigure the port.
1305 static void atmel_config_port(struct uart_port
*port
, int flags
)
1307 if (flags
& UART_CONFIG_TYPE
) {
1308 port
->type
= PORT_ATMEL
;
1309 atmel_request_port(port
);
1314 * Verify the new serial_struct (for TIOCSSERIAL).
1316 static int atmel_verify_port(struct uart_port
*port
, struct serial_struct
*ser
)
1319 if (ser
->type
!= PORT_UNKNOWN
&& ser
->type
!= PORT_ATMEL
)
1321 if (port
->irq
!= ser
->irq
)
1323 if (ser
->io_type
!= SERIAL_IO_MEM
)
1325 if (port
->uartclk
/ 16 != ser
->baud_base
)
1327 if ((void *)port
->mapbase
!= ser
->iomem_base
)
1329 if (port
->iobase
!= ser
->port
)
1336 #ifdef CONFIG_CONSOLE_POLL
1337 static int atmel_poll_get_char(struct uart_port
*port
)
1339 while (!(UART_GET_CSR(port
) & ATMEL_US_RXRDY
))
1342 return UART_GET_CHAR(port
);
1345 static void atmel_poll_put_char(struct uart_port
*port
, unsigned char ch
)
1347 while (!(UART_GET_CSR(port
) & ATMEL_US_TXRDY
))
1350 UART_PUT_CHAR(port
, ch
);
1355 atmel_ioctl(struct uart_port
*port
, unsigned int cmd
, unsigned long arg
)
1357 struct serial_rs485 rs485conf
;
1361 if (copy_from_user(&rs485conf
, (struct serial_rs485
*) arg
,
1365 atmel_config_rs485(port
, &rs485conf
);
1369 if (copy_to_user((struct serial_rs485
*) arg
,
1370 &(to_atmel_uart_port(port
)->rs485
),
1376 return -ENOIOCTLCMD
;
1383 static struct uart_ops atmel_pops
= {
1384 .tx_empty
= atmel_tx_empty
,
1385 .set_mctrl
= atmel_set_mctrl
,
1386 .get_mctrl
= atmel_get_mctrl
,
1387 .stop_tx
= atmel_stop_tx
,
1388 .start_tx
= atmel_start_tx
,
1389 .stop_rx
= atmel_stop_rx
,
1390 .enable_ms
= atmel_enable_ms
,
1391 .break_ctl
= atmel_break_ctl
,
1392 .startup
= atmel_startup
,
1393 .shutdown
= atmel_shutdown
,
1394 .flush_buffer
= atmel_flush_buffer
,
1395 .set_termios
= atmel_set_termios
,
1396 .set_ldisc
= atmel_set_ldisc
,
1398 .release_port
= atmel_release_port
,
1399 .request_port
= atmel_request_port
,
1400 .config_port
= atmel_config_port
,
1401 .verify_port
= atmel_verify_port
,
1402 .pm
= atmel_serial_pm
,
1403 .ioctl
= atmel_ioctl
,
1404 #ifdef CONFIG_CONSOLE_POLL
1405 .poll_get_char
= atmel_poll_get_char
,
1406 .poll_put_char
= atmel_poll_put_char
,
1411 * Configure the port from the platform device resource info.
1413 static void __devinit
atmel_init_port(struct atmel_uart_port
*atmel_port
,
1414 struct platform_device
*pdev
)
1416 struct uart_port
*port
= &atmel_port
->uart
;
1417 struct atmel_uart_data
*data
= pdev
->dev
.platform_data
;
1419 port
->iotype
= UPIO_MEM
;
1420 port
->flags
= UPF_BOOT_AUTOCONF
;
1421 port
->ops
= &atmel_pops
;
1423 port
->line
= data
->num
;
1424 port
->dev
= &pdev
->dev
;
1425 port
->mapbase
= pdev
->resource
[0].start
;
1426 port
->irq
= pdev
->resource
[1].start
;
1428 tasklet_init(&atmel_port
->tasklet
, atmel_tasklet_func
,
1429 (unsigned long)port
);
1431 memset(&atmel_port
->rx_ring
, 0, sizeof(atmel_port
->rx_ring
));
1434 /* Already mapped by setup code */
1435 port
->membase
= data
->regs
;
1437 port
->flags
|= UPF_IOREMAP
;
1438 port
->membase
= NULL
;
1441 /* for console, the clock could already be configured */
1442 if (!atmel_port
->clk
) {
1443 atmel_port
->clk
= clk_get(&pdev
->dev
, "usart");
1444 clk_enable(atmel_port
->clk
);
1445 port
->uartclk
= clk_get_rate(atmel_port
->clk
);
1446 clk_disable(atmel_port
->clk
);
1447 /* only enable clock when USART is in use */
1450 atmel_port
->use_dma_rx
= data
->use_dma_rx
;
1451 atmel_port
->use_dma_tx
= data
->use_dma_tx
;
1452 atmel_port
->rs485
= data
->rs485
;
1453 /* Use TXEMPTY for interrupt when rs485 else TXRDY or ENDTX|TXBUFE */
1454 if (atmel_port
->rs485
.flags
& SER_RS485_ENABLED
)
1455 atmel_port
->tx_done_mask
= ATMEL_US_TXEMPTY
;
1456 else if (atmel_use_dma_tx(port
)) {
1457 port
->fifosize
= PDC_BUFFER_SIZE
;
1458 atmel_port
->tx_done_mask
= ATMEL_US_ENDTX
| ATMEL_US_TXBUFE
;
1460 atmel_port
->tx_done_mask
= ATMEL_US_TXRDY
;
1465 * Register board-specific modem-control line handlers.
1467 void __init
atmel_register_uart_fns(struct atmel_port_fns
*fns
)
1470 atmel_pops
.enable_ms
= fns
->enable_ms
;
1472 atmel_pops
.get_mctrl
= fns
->get_mctrl
;
1474 atmel_pops
.set_mctrl
= fns
->set_mctrl
;
1475 atmel_open_hook
= fns
->open
;
1476 atmel_close_hook
= fns
->close
;
1477 atmel_pops
.pm
= fns
->pm
;
1478 atmel_pops
.set_wake
= fns
->set_wake
;
1481 #ifdef CONFIG_SERIAL_ATMEL_CONSOLE
1482 static void atmel_console_putchar(struct uart_port
*port
, int ch
)
1484 while (!(UART_GET_CSR(port
) & ATMEL_US_TXRDY
))
1486 UART_PUT_CHAR(port
, ch
);
1490 * Interrupts are disabled on entering
1492 static void atmel_console_write(struct console
*co
, const char *s
, u_int count
)
1494 struct uart_port
*port
= &atmel_ports
[co
->index
].uart
;
1495 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1496 unsigned int status
, imr
;
1497 unsigned int pdc_tx
;
1500 * First, save IMR and then disable interrupts
1502 imr
= UART_GET_IMR(port
);
1503 UART_PUT_IDR(port
, ATMEL_US_RXRDY
| atmel_port
->tx_done_mask
);
1505 /* Store PDC transmit status and disable it */
1506 pdc_tx
= UART_GET_PTSR(port
) & ATMEL_PDC_TXTEN
;
1507 UART_PUT_PTCR(port
, ATMEL_PDC_TXTDIS
);
1509 uart_console_write(port
, s
, count
, atmel_console_putchar
);
1512 * Finally, wait for transmitter to become empty
1516 status
= UART_GET_CSR(port
);
1517 } while (!(status
& ATMEL_US_TXRDY
));
1519 /* Restore PDC transmit status */
1521 UART_PUT_PTCR(port
, ATMEL_PDC_TXTEN
);
1523 /* set interrupts back the way they were */
1524 UART_PUT_IER(port
, imr
);
1528 * If the port was already initialised (eg, by a boot loader),
1529 * try to determine the current setup.
1531 static void __init
atmel_console_get_options(struct uart_port
*port
, int *baud
,
1532 int *parity
, int *bits
)
1534 unsigned int mr
, quot
;
1537 * If the baud rate generator isn't running, the port wasn't
1538 * initialized by the boot loader.
1540 quot
= UART_GET_BRGR(port
) & ATMEL_US_CD
;
1544 mr
= UART_GET_MR(port
) & ATMEL_US_CHRL
;
1545 if (mr
== ATMEL_US_CHRL_8
)
1550 mr
= UART_GET_MR(port
) & ATMEL_US_PAR
;
1551 if (mr
== ATMEL_US_PAR_EVEN
)
1553 else if (mr
== ATMEL_US_PAR_ODD
)
1557 * The serial core only rounds down when matching this to a
1558 * supported baud rate. Make sure we don't end up slightly
1559 * lower than one of those, as it would make us fall through
1560 * to a much lower baud rate than we really want.
1562 *baud
= port
->uartclk
/ (16 * (quot
- 1));
1565 static int __init
atmel_console_setup(struct console
*co
, char *options
)
1567 struct uart_port
*port
= &atmel_ports
[co
->index
].uart
;
1573 if (port
->membase
== NULL
) {
1574 /* Port not initialized yet - delay setup */
1578 clk_enable(atmel_ports
[co
->index
].clk
);
1580 UART_PUT_IDR(port
, -1);
1581 UART_PUT_CR(port
, ATMEL_US_RSTSTA
| ATMEL_US_RSTRX
);
1582 UART_PUT_CR(port
, ATMEL_US_TXEN
| ATMEL_US_RXEN
);
1585 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
1587 atmel_console_get_options(port
, &baud
, &parity
, &bits
);
1589 return uart_set_options(port
, co
, baud
, parity
, bits
, flow
);
1592 static struct uart_driver atmel_uart
;
1594 static struct console atmel_console
= {
1595 .name
= ATMEL_DEVICENAME
,
1596 .write
= atmel_console_write
,
1597 .device
= uart_console_device
,
1598 .setup
= atmel_console_setup
,
1599 .flags
= CON_PRINTBUFFER
,
1601 .data
= &atmel_uart
,
1604 #define ATMEL_CONSOLE_DEVICE (&atmel_console)
1607 * Early console initialization (before VM subsystem initialized).
1609 static int __init
atmel_console_init(void)
1611 if (atmel_default_console_device
) {
1612 add_preferred_console(ATMEL_DEVICENAME
,
1613 atmel_default_console_device
->id
, NULL
);
1614 atmel_init_port(&atmel_ports
[atmel_default_console_device
->id
],
1615 atmel_default_console_device
);
1616 register_console(&atmel_console
);
1622 console_initcall(atmel_console_init
);
1625 * Late console initialization.
1627 static int __init
atmel_late_console_init(void)
1629 if (atmel_default_console_device
1630 && !(atmel_console
.flags
& CON_ENABLED
))
1631 register_console(&atmel_console
);
1636 core_initcall(atmel_late_console_init
);
1638 static inline bool atmel_is_console_port(struct uart_port
*port
)
1640 return port
->cons
&& port
->cons
->index
== port
->line
;
1644 #define ATMEL_CONSOLE_DEVICE NULL
1646 static inline bool atmel_is_console_port(struct uart_port
*port
)
1652 static struct uart_driver atmel_uart
= {
1653 .owner
= THIS_MODULE
,
1654 .driver_name
= "atmel_serial",
1655 .dev_name
= ATMEL_DEVICENAME
,
1656 .major
= SERIAL_ATMEL_MAJOR
,
1657 .minor
= MINOR_START
,
1658 .nr
= ATMEL_MAX_UART
,
1659 .cons
= ATMEL_CONSOLE_DEVICE
,
1663 static bool atmel_serial_clk_will_stop(void)
1665 #ifdef CONFIG_ARCH_AT91
1666 return at91_suspend_entering_slow_clock();
1672 static int atmel_serial_suspend(struct platform_device
*pdev
,
1675 struct uart_port
*port
= platform_get_drvdata(pdev
);
1676 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1678 if (atmel_is_console_port(port
) && console_suspend_enabled
) {
1679 /* Drain the TX shifter */
1680 while (!(UART_GET_CSR(port
) & ATMEL_US_TXEMPTY
))
1684 /* we can not wake up if we're running on slow clock */
1685 atmel_port
->may_wakeup
= device_may_wakeup(&pdev
->dev
);
1686 if (atmel_serial_clk_will_stop())
1687 device_set_wakeup_enable(&pdev
->dev
, 0);
1689 uart_suspend_port(&atmel_uart
, port
);
1694 static int atmel_serial_resume(struct platform_device
*pdev
)
1696 struct uart_port
*port
= platform_get_drvdata(pdev
);
1697 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1699 uart_resume_port(&atmel_uart
, port
);
1700 device_set_wakeup_enable(&pdev
->dev
, atmel_port
->may_wakeup
);
1705 #define atmel_serial_suspend NULL
1706 #define atmel_serial_resume NULL
1709 static int __devinit
atmel_serial_probe(struct platform_device
*pdev
)
1711 struct atmel_uart_port
*port
;
1712 struct atmel_uart_data
*pdata
= pdev
->dev
.platform_data
;
1716 BUILD_BUG_ON(ATMEL_SERIAL_RINGSIZE
& (ATMEL_SERIAL_RINGSIZE
- 1));
1718 port
= &atmel_ports
[pdata
->num
];
1719 port
->backup_imr
= 0;
1721 atmel_init_port(port
, pdev
);
1723 if (!atmel_use_dma_rx(&port
->uart
)) {
1725 data
= kmalloc(sizeof(struct atmel_uart_char
)
1726 * ATMEL_SERIAL_RINGSIZE
, GFP_KERNEL
);
1728 goto err_alloc_ring
;
1729 port
->rx_ring
.buf
= data
;
1732 ret
= uart_add_one_port(&atmel_uart
, &port
->uart
);
1736 #ifdef CONFIG_SERIAL_ATMEL_CONSOLE
1737 if (atmel_is_console_port(&port
->uart
)
1738 && ATMEL_CONSOLE_DEVICE
->flags
& CON_ENABLED
) {
1740 * The serial core enabled the clock for us, so undo
1741 * the clk_enable() in atmel_console_setup()
1743 clk_disable(port
->clk
);
1747 device_init_wakeup(&pdev
->dev
, 1);
1748 platform_set_drvdata(pdev
, port
);
1750 if (port
->rs485
.flags
& SER_RS485_ENABLED
) {
1751 UART_PUT_MR(&port
->uart
, ATMEL_US_USMODE_NORMAL
);
1752 UART_PUT_CR(&port
->uart
, ATMEL_US_RTSEN
);
1758 kfree(port
->rx_ring
.buf
);
1759 port
->rx_ring
.buf
= NULL
;
1761 if (!atmel_is_console_port(&port
->uart
)) {
1769 static int __devexit
atmel_serial_remove(struct platform_device
*pdev
)
1771 struct uart_port
*port
= platform_get_drvdata(pdev
);
1772 struct atmel_uart_port
*atmel_port
= to_atmel_uart_port(port
);
1775 device_init_wakeup(&pdev
->dev
, 0);
1776 platform_set_drvdata(pdev
, NULL
);
1778 ret
= uart_remove_one_port(&atmel_uart
, port
);
1780 tasklet_kill(&atmel_port
->tasklet
);
1781 kfree(atmel_port
->rx_ring
.buf
);
1783 /* "port" is allocated statically, so we shouldn't free it */
1785 clk_put(atmel_port
->clk
);
1790 static struct platform_driver atmel_serial_driver
= {
1791 .probe
= atmel_serial_probe
,
1792 .remove
= __devexit_p(atmel_serial_remove
),
1793 .suspend
= atmel_serial_suspend
,
1794 .resume
= atmel_serial_resume
,
1796 .name
= "atmel_usart",
1797 .owner
= THIS_MODULE
,
1801 static int __init
atmel_serial_init(void)
1805 ret
= uart_register_driver(&atmel_uart
);
1809 ret
= platform_driver_register(&atmel_serial_driver
);
1811 uart_unregister_driver(&atmel_uart
);
1816 static void __exit
atmel_serial_exit(void)
1818 platform_driver_unregister(&atmel_serial_driver
);
1819 uart_unregister_driver(&atmel_uart
);
1822 module_init(atmel_serial_init
);
1823 module_exit(atmel_serial_exit
);
1825 MODULE_AUTHOR("Rick Bronson");
1826 MODULE_DESCRIPTION("Atmel AT91 / AT32 serial port driver");
1827 MODULE_LICENSE("GPL");
1828 MODULE_ALIAS("platform:atmel_usart");