vfs: Fix vmtruncate() regression
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / serial / sunsab.c
blobd514e28d07557b7516de0ecd7478d1cb9401f619
1 /* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC.
3 * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
4 * Copyright (C) 2002, 2006 David S. Miller (davem@davemloft.net)
6 * Rewrote buffer handling to use CIRC(Circular Buffer) macros.
7 * Maxim Krasnyanskiy <maxk@qualcomm.com>
9 * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud
10 * rates to be programmed into the UART. Also eliminated a lot of
11 * duplicated code in the console setup.
12 * Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
14 * Ported to new 2.5.x UART layer.
15 * David S. Miller <davem@davemloft.net>
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/errno.h>
21 #include <linux/tty.h>
22 #include <linux/tty_flip.h>
23 #include <linux/major.h>
24 #include <linux/string.h>
25 #include <linux/ptrace.h>
26 #include <linux/ioport.h>
27 #include <linux/circ_buf.h>
28 #include <linux/serial.h>
29 #include <linux/sysrq.h>
30 #include <linux/console.h>
31 #include <linux/spinlock.h>
32 #include <linux/slab.h>
33 #include <linux/delay.h>
34 #include <linux/init.h>
35 #include <linux/of_device.h>
37 #include <asm/io.h>
38 #include <asm/irq.h>
39 #include <asm/prom.h>
41 #if defined(CONFIG_SERIAL_SUNSAB_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
42 #define SUPPORT_SYSRQ
43 #endif
45 #include <linux/serial_core.h>
47 #include "suncore.h"
48 #include "sunsab.h"
50 struct uart_sunsab_port {
51 struct uart_port port; /* Generic UART port */
52 union sab82532_async_regs __iomem *regs; /* Chip registers */
53 unsigned long irqflags; /* IRQ state flags */
54 int dsr; /* Current DSR state */
55 unsigned int cec_timeout; /* Chip poll timeout... */
56 unsigned int tec_timeout; /* likewise */
57 unsigned char interrupt_mask0;/* ISR0 masking */
58 unsigned char interrupt_mask1;/* ISR1 masking */
59 unsigned char pvr_dtr_bit; /* Which PVR bit is DTR */
60 unsigned char pvr_dsr_bit; /* Which PVR bit is DSR */
61 unsigned int gis_shift;
62 int type; /* SAB82532 version */
64 /* Setting configuration bits while the transmitter is active
65 * can cause garbage characters to get emitted by the chip.
66 * Therefore, we cache such writes here and do the real register
67 * write the next time the transmitter becomes idle.
69 unsigned int cached_ebrg;
70 unsigned char cached_mode;
71 unsigned char cached_pvr;
72 unsigned char cached_dafo;
76 * This assumes you have a 29.4912 MHz clock for your UART.
78 #define SAB_BASE_BAUD ( 29491200 / 16 )
80 static char *sab82532_version[16] = {
81 "V1.0", "V2.0", "V3.2", "V(0x03)",
82 "V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
83 "V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
84 "V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
87 #define SAB82532_MAX_TEC_TIMEOUT 200000 /* 1 character time (at 50 baud) */
88 #define SAB82532_MAX_CEC_TIMEOUT 50000 /* 2.5 TX CLKs (at 50 baud) */
90 #define SAB82532_RECV_FIFO_SIZE 32 /* Standard async fifo sizes */
91 #define SAB82532_XMIT_FIFO_SIZE 32
93 static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
95 int timeout = up->tec_timeout;
97 while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
98 udelay(1);
101 static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
103 int timeout = up->cec_timeout;
105 while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
106 udelay(1);
109 static struct tty_struct *
110 receive_chars(struct uart_sunsab_port *up,
111 union sab82532_irq_status *stat)
113 struct tty_struct *tty = NULL;
114 unsigned char buf[32];
115 int saw_console_brk = 0;
116 int free_fifo = 0;
117 int count = 0;
118 int i;
120 if (up->port.state != NULL) /* Unopened serial console */
121 tty = up->port.state->port.tty;
123 /* Read number of BYTES (Character + Status) available. */
124 if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
125 count = SAB82532_RECV_FIFO_SIZE;
126 free_fifo++;
129 if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
130 count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
131 free_fifo++;
134 /* Issue a FIFO read command in case we where idle. */
135 if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
136 sunsab_cec_wait(up);
137 writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
138 return tty;
141 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
142 free_fifo++;
144 /* Read the FIFO. */
145 for (i = 0; i < count; i++)
146 buf[i] = readb(&up->regs->r.rfifo[i]);
148 /* Issue Receive Message Complete command. */
149 if (free_fifo) {
150 sunsab_cec_wait(up);
151 writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
154 /* Count may be zero for BRK, so we check for it here */
155 if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
156 (up->port.line == up->port.cons->index))
157 saw_console_brk = 1;
159 for (i = 0; i < count; i++) {
160 unsigned char ch = buf[i], flag;
162 if (tty == NULL) {
163 uart_handle_sysrq_char(&up->port, ch);
164 continue;
167 flag = TTY_NORMAL;
168 up->port.icount.rx++;
170 if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
171 SAB82532_ISR0_FERR |
172 SAB82532_ISR0_RFO)) ||
173 unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
175 * For statistics only
177 if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
178 stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
179 SAB82532_ISR0_FERR);
180 up->port.icount.brk++;
182 * We do the SysRQ and SAK checking
183 * here because otherwise the break
184 * may get masked by ignore_status_mask
185 * or read_status_mask.
187 if (uart_handle_break(&up->port))
188 continue;
189 } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
190 up->port.icount.parity++;
191 else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
192 up->port.icount.frame++;
193 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
194 up->port.icount.overrun++;
197 * Mask off conditions which should be ingored.
199 stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
200 stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
202 if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
203 flag = TTY_BREAK;
204 } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
205 flag = TTY_PARITY;
206 else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
207 flag = TTY_FRAME;
210 if (uart_handle_sysrq_char(&up->port, ch))
211 continue;
213 if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
214 (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
215 tty_insert_flip_char(tty, ch, flag);
216 if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
217 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
220 if (saw_console_brk)
221 sun_do_break();
223 return tty;
226 static void sunsab_stop_tx(struct uart_port *);
227 static void sunsab_tx_idle(struct uart_sunsab_port *);
229 static void transmit_chars(struct uart_sunsab_port *up,
230 union sab82532_irq_status *stat)
232 struct circ_buf *xmit = &up->port.state->xmit;
233 int i;
235 if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
236 up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
237 writeb(up->interrupt_mask1, &up->regs->w.imr1);
238 set_bit(SAB82532_ALLS, &up->irqflags);
241 #if 0 /* bde@nwlink.com says this check causes problems */
242 if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
243 return;
244 #endif
246 if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
247 return;
249 set_bit(SAB82532_XPR, &up->irqflags);
250 sunsab_tx_idle(up);
252 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
253 up->interrupt_mask1 |= SAB82532_IMR1_XPR;
254 writeb(up->interrupt_mask1, &up->regs->w.imr1);
255 return;
258 up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
259 writeb(up->interrupt_mask1, &up->regs->w.imr1);
260 clear_bit(SAB82532_ALLS, &up->irqflags);
262 /* Stuff 32 bytes into Transmit FIFO. */
263 clear_bit(SAB82532_XPR, &up->irqflags);
264 for (i = 0; i < up->port.fifosize; i++) {
265 writeb(xmit->buf[xmit->tail],
266 &up->regs->w.xfifo[i]);
267 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
268 up->port.icount.tx++;
269 if (uart_circ_empty(xmit))
270 break;
273 /* Issue a Transmit Frame command. */
274 sunsab_cec_wait(up);
275 writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
277 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
278 uart_write_wakeup(&up->port);
280 if (uart_circ_empty(xmit))
281 sunsab_stop_tx(&up->port);
284 static void check_status(struct uart_sunsab_port *up,
285 union sab82532_irq_status *stat)
287 if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
288 uart_handle_dcd_change(&up->port,
289 !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
291 if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
292 uart_handle_cts_change(&up->port,
293 (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
295 if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
296 up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
297 up->port.icount.dsr++;
300 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
303 static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
305 struct uart_sunsab_port *up = dev_id;
306 struct tty_struct *tty;
307 union sab82532_irq_status status;
308 unsigned long flags;
309 unsigned char gis;
311 spin_lock_irqsave(&up->port.lock, flags);
313 status.stat = 0;
314 gis = readb(&up->regs->r.gis) >> up->gis_shift;
315 if (gis & 1)
316 status.sreg.isr0 = readb(&up->regs->r.isr0);
317 if (gis & 2)
318 status.sreg.isr1 = readb(&up->regs->r.isr1);
320 tty = NULL;
321 if (status.stat) {
322 if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
323 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
324 (status.sreg.isr1 & SAB82532_ISR1_BRK))
325 tty = receive_chars(up, &status);
326 if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
327 (status.sreg.isr1 & SAB82532_ISR1_CSC))
328 check_status(up, &status);
329 if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
330 transmit_chars(up, &status);
333 spin_unlock_irqrestore(&up->port.lock, flags);
335 if (tty)
336 tty_flip_buffer_push(tty);
338 return IRQ_HANDLED;
341 /* port->lock is not held. */
342 static unsigned int sunsab_tx_empty(struct uart_port *port)
344 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
345 int ret;
347 /* Do not need a lock for a state test like this. */
348 if (test_bit(SAB82532_ALLS, &up->irqflags))
349 ret = TIOCSER_TEMT;
350 else
351 ret = 0;
353 return ret;
356 /* port->lock held by caller. */
357 static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
359 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
361 if (mctrl & TIOCM_RTS) {
362 up->cached_mode &= ~SAB82532_MODE_FRTS;
363 up->cached_mode |= SAB82532_MODE_RTS;
364 } else {
365 up->cached_mode |= (SAB82532_MODE_FRTS |
366 SAB82532_MODE_RTS);
368 if (mctrl & TIOCM_DTR) {
369 up->cached_pvr &= ~(up->pvr_dtr_bit);
370 } else {
371 up->cached_pvr |= up->pvr_dtr_bit;
374 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
375 if (test_bit(SAB82532_XPR, &up->irqflags))
376 sunsab_tx_idle(up);
379 /* port->lock is held by caller and interrupts are disabled. */
380 static unsigned int sunsab_get_mctrl(struct uart_port *port)
382 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
383 unsigned char val;
384 unsigned int result;
386 result = 0;
388 val = readb(&up->regs->r.pvr);
389 result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
391 val = readb(&up->regs->r.vstr);
392 result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
394 val = readb(&up->regs->r.star);
395 result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
397 return result;
400 /* port->lock held by caller. */
401 static void sunsab_stop_tx(struct uart_port *port)
403 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
405 up->interrupt_mask1 |= SAB82532_IMR1_XPR;
406 writeb(up->interrupt_mask1, &up->regs->w.imr1);
409 /* port->lock held by caller. */
410 static void sunsab_tx_idle(struct uart_sunsab_port *up)
412 if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
413 u8 tmp;
415 clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
416 writeb(up->cached_mode, &up->regs->rw.mode);
417 writeb(up->cached_pvr, &up->regs->rw.pvr);
418 writeb(up->cached_dafo, &up->regs->w.dafo);
420 writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
421 tmp = readb(&up->regs->rw.ccr2);
422 tmp &= ~0xc0;
423 tmp |= (up->cached_ebrg >> 2) & 0xc0;
424 writeb(tmp, &up->regs->rw.ccr2);
428 /* port->lock held by caller. */
429 static void sunsab_start_tx(struct uart_port *port)
431 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
432 struct circ_buf *xmit = &up->port.state->xmit;
433 int i;
435 up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
436 writeb(up->interrupt_mask1, &up->regs->w.imr1);
438 if (!test_bit(SAB82532_XPR, &up->irqflags))
439 return;
441 clear_bit(SAB82532_ALLS, &up->irqflags);
442 clear_bit(SAB82532_XPR, &up->irqflags);
444 for (i = 0; i < up->port.fifosize; i++) {
445 writeb(xmit->buf[xmit->tail],
446 &up->regs->w.xfifo[i]);
447 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
448 up->port.icount.tx++;
449 if (uart_circ_empty(xmit))
450 break;
453 /* Issue a Transmit Frame command. */
454 sunsab_cec_wait(up);
455 writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
458 /* port->lock is not held. */
459 static void sunsab_send_xchar(struct uart_port *port, char ch)
461 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
462 unsigned long flags;
464 spin_lock_irqsave(&up->port.lock, flags);
466 sunsab_tec_wait(up);
467 writeb(ch, &up->regs->w.tic);
469 spin_unlock_irqrestore(&up->port.lock, flags);
472 /* port->lock held by caller. */
473 static void sunsab_stop_rx(struct uart_port *port)
475 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
477 up->interrupt_mask0 |= SAB82532_ISR0_TCD;
478 writeb(up->interrupt_mask1, &up->regs->w.imr0);
481 /* port->lock held by caller. */
482 static void sunsab_enable_ms(struct uart_port *port)
484 /* For now we always receive these interrupts. */
487 /* port->lock is not held. */
488 static void sunsab_break_ctl(struct uart_port *port, int break_state)
490 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
491 unsigned long flags;
492 unsigned char val;
494 spin_lock_irqsave(&up->port.lock, flags);
496 val = up->cached_dafo;
497 if (break_state)
498 val |= SAB82532_DAFO_XBRK;
499 else
500 val &= ~SAB82532_DAFO_XBRK;
501 up->cached_dafo = val;
503 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
504 if (test_bit(SAB82532_XPR, &up->irqflags))
505 sunsab_tx_idle(up);
507 spin_unlock_irqrestore(&up->port.lock, flags);
510 /* port->lock is not held. */
511 static int sunsab_startup(struct uart_port *port)
513 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
514 unsigned long flags;
515 unsigned char tmp;
516 int err = request_irq(up->port.irq, sunsab_interrupt,
517 IRQF_SHARED, "sab", up);
518 if (err)
519 return err;
521 spin_lock_irqsave(&up->port.lock, flags);
524 * Wait for any commands or immediate characters
526 sunsab_cec_wait(up);
527 sunsab_tec_wait(up);
530 * Clear the FIFO buffers.
532 writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
533 sunsab_cec_wait(up);
534 writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
537 * Clear the interrupt registers.
539 (void) readb(&up->regs->r.isr0);
540 (void) readb(&up->regs->r.isr1);
543 * Now, initialize the UART
545 writeb(0, &up->regs->w.ccr0); /* power-down */
546 writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
547 SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
548 writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
549 writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
550 SAB82532_CCR2_TOE, &up->regs->w.ccr2);
551 writeb(0, &up->regs->w.ccr3);
552 writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
553 up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
554 SAB82532_MODE_RAC);
555 writeb(up->cached_mode, &up->regs->w.mode);
556 writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
558 tmp = readb(&up->regs->rw.ccr0);
559 tmp |= SAB82532_CCR0_PU; /* power-up */
560 writeb(tmp, &up->regs->rw.ccr0);
563 * Finally, enable interrupts
565 up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
566 SAB82532_IMR0_PLLA);
567 writeb(up->interrupt_mask0, &up->regs->w.imr0);
568 up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
569 SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
570 SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
571 SAB82532_IMR1_XPR);
572 writeb(up->interrupt_mask1, &up->regs->w.imr1);
573 set_bit(SAB82532_ALLS, &up->irqflags);
574 set_bit(SAB82532_XPR, &up->irqflags);
576 spin_unlock_irqrestore(&up->port.lock, flags);
578 return 0;
581 /* port->lock is not held. */
582 static void sunsab_shutdown(struct uart_port *port)
584 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
585 unsigned long flags;
587 spin_lock_irqsave(&up->port.lock, flags);
589 /* Disable Interrupts */
590 up->interrupt_mask0 = 0xff;
591 writeb(up->interrupt_mask0, &up->regs->w.imr0);
592 up->interrupt_mask1 = 0xff;
593 writeb(up->interrupt_mask1, &up->regs->w.imr1);
595 /* Disable break condition */
596 up->cached_dafo = readb(&up->regs->rw.dafo);
597 up->cached_dafo &= ~SAB82532_DAFO_XBRK;
598 writeb(up->cached_dafo, &up->regs->rw.dafo);
600 /* Disable Receiver */
601 up->cached_mode &= ~SAB82532_MODE_RAC;
602 writeb(up->cached_mode, &up->regs->rw.mode);
605 * XXX FIXME
607 * If the chip is powered down here the system hangs/crashes during
608 * reboot or shutdown. This needs to be investigated further,
609 * similar behaviour occurs in 2.4 when the driver is configured
610 * as a module only. One hint may be that data is sometimes
611 * transmitted at 9600 baud during shutdown (regardless of the
612 * speed the chip was configured for when the port was open).
614 #if 0
615 /* Power Down */
616 tmp = readb(&up->regs->rw.ccr0);
617 tmp &= ~SAB82532_CCR0_PU;
618 writeb(tmp, &up->regs->rw.ccr0);
619 #endif
621 spin_unlock_irqrestore(&up->port.lock, flags);
622 free_irq(up->port.irq, up);
626 * This is used to figure out the divisor speeds.
628 * The formula is: Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
630 * with 0 <= N < 64 and 0 <= M < 16
633 static void calc_ebrg(int baud, int *n_ret, int *m_ret)
635 int n, m;
637 if (baud == 0) {
638 *n_ret = 0;
639 *m_ret = 0;
640 return;
644 * We scale numbers by 10 so that we get better accuracy
645 * without having to use floating point. Here we increment m
646 * until n is within the valid range.
648 n = (SAB_BASE_BAUD * 10) / baud;
649 m = 0;
650 while (n >= 640) {
651 n = n / 2;
652 m++;
654 n = (n+5) / 10;
656 * We try very hard to avoid speeds with M == 0 since they may
657 * not work correctly for XTAL frequences above 10 MHz.
659 if ((m == 0) && ((n & 1) == 0)) {
660 n = n / 2;
661 m++;
663 *n_ret = n - 1;
664 *m_ret = m;
667 /* Internal routine, port->lock is held and local interrupts are disabled. */
668 static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
669 unsigned int iflag, unsigned int baud,
670 unsigned int quot)
672 unsigned char dafo;
673 int bits, n, m;
675 /* Byte size and parity */
676 switch (cflag & CSIZE) {
677 case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
678 case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
679 case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
680 case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
681 /* Never happens, but GCC is too dumb to figure it out */
682 default: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
685 if (cflag & CSTOPB) {
686 dafo |= SAB82532_DAFO_STOP;
687 bits++;
690 if (cflag & PARENB) {
691 dafo |= SAB82532_DAFO_PARE;
692 bits++;
695 if (cflag & PARODD) {
696 dafo |= SAB82532_DAFO_PAR_ODD;
697 } else {
698 dafo |= SAB82532_DAFO_PAR_EVEN;
700 up->cached_dafo = dafo;
702 calc_ebrg(baud, &n, &m);
704 up->cached_ebrg = n | (m << 6);
706 up->tec_timeout = (10 * 1000000) / baud;
707 up->cec_timeout = up->tec_timeout >> 2;
709 /* CTS flow control flags */
710 /* We encode read_status_mask and ignore_status_mask like so:
712 * ---------------------
713 * | ... | ISR1 | ISR0 |
714 * ---------------------
715 * .. 15 8 7 0
718 up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
719 SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
720 SAB82532_ISR0_CDSC);
721 up->port.read_status_mask |= (SAB82532_ISR1_CSC |
722 SAB82532_ISR1_ALLS |
723 SAB82532_ISR1_XPR) << 8;
724 if (iflag & INPCK)
725 up->port.read_status_mask |= (SAB82532_ISR0_PERR |
726 SAB82532_ISR0_FERR);
727 if (iflag & (BRKINT | PARMRK))
728 up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
731 * Characteres to ignore
733 up->port.ignore_status_mask = 0;
734 if (iflag & IGNPAR)
735 up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
736 SAB82532_ISR0_FERR);
737 if (iflag & IGNBRK) {
738 up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
740 * If we're ignoring parity and break indicators,
741 * ignore overruns too (for real raw support).
743 if (iflag & IGNPAR)
744 up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
748 * ignore all characters if CREAD is not set
750 if ((cflag & CREAD) == 0)
751 up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
752 SAB82532_ISR0_TCD);
754 uart_update_timeout(&up->port, cflag,
755 (up->port.uartclk / (16 * quot)));
757 /* Now schedule a register update when the chip's
758 * transmitter is idle.
760 up->cached_mode |= SAB82532_MODE_RAC;
761 set_bit(SAB82532_REGS_PENDING, &up->irqflags);
762 if (test_bit(SAB82532_XPR, &up->irqflags))
763 sunsab_tx_idle(up);
766 /* port->lock is not held. */
767 static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
768 struct ktermios *old)
770 struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
771 unsigned long flags;
772 unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
773 unsigned int quot = uart_get_divisor(port, baud);
775 spin_lock_irqsave(&up->port.lock, flags);
776 sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
777 spin_unlock_irqrestore(&up->port.lock, flags);
780 static const char *sunsab_type(struct uart_port *port)
782 struct uart_sunsab_port *up = (void *)port;
783 static char buf[36];
785 sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
786 return buf;
789 static void sunsab_release_port(struct uart_port *port)
793 static int sunsab_request_port(struct uart_port *port)
795 return 0;
798 static void sunsab_config_port(struct uart_port *port, int flags)
802 static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
804 return -EINVAL;
807 static struct uart_ops sunsab_pops = {
808 .tx_empty = sunsab_tx_empty,
809 .set_mctrl = sunsab_set_mctrl,
810 .get_mctrl = sunsab_get_mctrl,
811 .stop_tx = sunsab_stop_tx,
812 .start_tx = sunsab_start_tx,
813 .send_xchar = sunsab_send_xchar,
814 .stop_rx = sunsab_stop_rx,
815 .enable_ms = sunsab_enable_ms,
816 .break_ctl = sunsab_break_ctl,
817 .startup = sunsab_startup,
818 .shutdown = sunsab_shutdown,
819 .set_termios = sunsab_set_termios,
820 .type = sunsab_type,
821 .release_port = sunsab_release_port,
822 .request_port = sunsab_request_port,
823 .config_port = sunsab_config_port,
824 .verify_port = sunsab_verify_port,
827 static struct uart_driver sunsab_reg = {
828 .owner = THIS_MODULE,
829 .driver_name = "sunsab",
830 .dev_name = "ttyS",
831 .major = TTY_MAJOR,
834 static struct uart_sunsab_port *sunsab_ports;
836 #ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
838 static void sunsab_console_putchar(struct uart_port *port, int c)
840 struct uart_sunsab_port *up = (struct uart_sunsab_port *)port;
842 sunsab_tec_wait(up);
843 writeb(c, &up->regs->w.tic);
846 static void sunsab_console_write(struct console *con, const char *s, unsigned n)
848 struct uart_sunsab_port *up = &sunsab_ports[con->index];
849 unsigned long flags;
850 int locked = 1;
852 local_irq_save(flags);
853 if (up->port.sysrq) {
854 locked = 0;
855 } else if (oops_in_progress) {
856 locked = spin_trylock(&up->port.lock);
857 } else
858 spin_lock(&up->port.lock);
860 uart_console_write(&up->port, s, n, sunsab_console_putchar);
861 sunsab_tec_wait(up);
863 if (locked)
864 spin_unlock(&up->port.lock);
865 local_irq_restore(flags);
868 static int sunsab_console_setup(struct console *con, char *options)
870 struct uart_sunsab_port *up = &sunsab_ports[con->index];
871 unsigned long flags;
872 unsigned int baud, quot;
875 * The console framework calls us for each and every port
876 * registered. Defer the console setup until the requested
877 * port has been properly discovered. A bit of a hack,
878 * though...
880 if (up->port.type != PORT_SUNSAB)
881 return -1;
883 printk("Console: ttyS%d (SAB82532)\n",
884 (sunsab_reg.minor - 64) + con->index);
886 sunserial_console_termios(con, to_of_device(up->port.dev)->node);
888 switch (con->cflag & CBAUD) {
889 case B150: baud = 150; break;
890 case B300: baud = 300; break;
891 case B600: baud = 600; break;
892 case B1200: baud = 1200; break;
893 case B2400: baud = 2400; break;
894 case B4800: baud = 4800; break;
895 default: case B9600: baud = 9600; break;
896 case B19200: baud = 19200; break;
897 case B38400: baud = 38400; break;
898 case B57600: baud = 57600; break;
899 case B115200: baud = 115200; break;
900 case B230400: baud = 230400; break;
901 case B460800: baud = 460800; break;
905 * Temporary fix.
907 spin_lock_init(&up->port.lock);
910 * Initialize the hardware
912 sunsab_startup(&up->port);
914 spin_lock_irqsave(&up->port.lock, flags);
917 * Finally, enable interrupts
919 up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
920 SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
921 writeb(up->interrupt_mask0, &up->regs->w.imr0);
922 up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
923 SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
924 SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
925 SAB82532_IMR1_XPR;
926 writeb(up->interrupt_mask1, &up->regs->w.imr1);
928 quot = uart_get_divisor(&up->port, baud);
929 sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
930 sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
932 spin_unlock_irqrestore(&up->port.lock, flags);
934 return 0;
937 static struct console sunsab_console = {
938 .name = "ttyS",
939 .write = sunsab_console_write,
940 .device = uart_console_device,
941 .setup = sunsab_console_setup,
942 .flags = CON_PRINTBUFFER,
943 .index = -1,
944 .data = &sunsab_reg,
947 static inline struct console *SUNSAB_CONSOLE(void)
949 return &sunsab_console;
951 #else
952 #define SUNSAB_CONSOLE() (NULL)
953 #define sunsab_console_init() do { } while (0)
954 #endif
956 static int __devinit sunsab_init_one(struct uart_sunsab_port *up,
957 struct of_device *op,
958 unsigned long offset,
959 int line)
961 up->port.line = line;
962 up->port.dev = &op->dev;
964 up->port.mapbase = op->resource[0].start + offset;
965 up->port.membase = of_ioremap(&op->resource[0], offset,
966 sizeof(union sab82532_async_regs),
967 "sab");
968 if (!up->port.membase)
969 return -ENOMEM;
970 up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
972 up->port.irq = op->irqs[0];
974 up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
975 up->port.iotype = UPIO_MEM;
977 writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
979 up->port.ops = &sunsab_pops;
980 up->port.type = PORT_SUNSAB;
981 up->port.uartclk = SAB_BASE_BAUD;
983 up->type = readb(&up->regs->r.vstr) & 0x0f;
984 writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
985 writeb(0xff, &up->regs->w.pim);
986 if ((up->port.line & 0x1) == 0) {
987 up->pvr_dsr_bit = (1 << 0);
988 up->pvr_dtr_bit = (1 << 1);
989 up->gis_shift = 2;
990 } else {
991 up->pvr_dsr_bit = (1 << 3);
992 up->pvr_dtr_bit = (1 << 2);
993 up->gis_shift = 0;
995 up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
996 writeb(up->cached_pvr, &up->regs->w.pvr);
997 up->cached_mode = readb(&up->regs->rw.mode);
998 up->cached_mode |= SAB82532_MODE_FRTS;
999 writeb(up->cached_mode, &up->regs->rw.mode);
1000 up->cached_mode |= SAB82532_MODE_RTS;
1001 writeb(up->cached_mode, &up->regs->rw.mode);
1003 up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
1004 up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
1006 return 0;
1009 static int __devinit sab_probe(struct of_device *op, const struct of_device_id *match)
1011 static int inst;
1012 struct uart_sunsab_port *up;
1013 int err;
1015 up = &sunsab_ports[inst * 2];
1017 err = sunsab_init_one(&up[0], op,
1019 (inst * 2) + 0);
1020 if (err)
1021 goto out;
1023 err = sunsab_init_one(&up[1], op,
1024 sizeof(union sab82532_async_regs),
1025 (inst * 2) + 1);
1026 if (err)
1027 goto out1;
1029 sunserial_console_match(SUNSAB_CONSOLE(), op->node,
1030 &sunsab_reg, up[0].port.line,
1031 false);
1033 sunserial_console_match(SUNSAB_CONSOLE(), op->node,
1034 &sunsab_reg, up[1].port.line,
1035 false);
1037 err = uart_add_one_port(&sunsab_reg, &up[0].port);
1038 if (err)
1039 goto out2;
1041 err = uart_add_one_port(&sunsab_reg, &up[1].port);
1042 if (err)
1043 goto out3;
1045 dev_set_drvdata(&op->dev, &up[0]);
1047 inst++;
1049 return 0;
1051 out3:
1052 uart_remove_one_port(&sunsab_reg, &up[0].port);
1053 out2:
1054 of_iounmap(&op->resource[0],
1055 up[1].port.membase,
1056 sizeof(union sab82532_async_regs));
1057 out1:
1058 of_iounmap(&op->resource[0],
1059 up[0].port.membase,
1060 sizeof(union sab82532_async_regs));
1061 out:
1062 return err;
1065 static int __devexit sab_remove(struct of_device *op)
1067 struct uart_sunsab_port *up = dev_get_drvdata(&op->dev);
1069 uart_remove_one_port(&sunsab_reg, &up[1].port);
1070 uart_remove_one_port(&sunsab_reg, &up[0].port);
1071 of_iounmap(&op->resource[0],
1072 up[1].port.membase,
1073 sizeof(union sab82532_async_regs));
1074 of_iounmap(&op->resource[0],
1075 up[0].port.membase,
1076 sizeof(union sab82532_async_regs));
1078 dev_set_drvdata(&op->dev, NULL);
1080 return 0;
1083 static const struct of_device_id sab_match[] = {
1085 .name = "se",
1088 .name = "serial",
1089 .compatible = "sab82532",
1093 MODULE_DEVICE_TABLE(of, sab_match);
1095 static struct of_platform_driver sab_driver = {
1096 .name = "sab",
1097 .match_table = sab_match,
1098 .probe = sab_probe,
1099 .remove = __devexit_p(sab_remove),
1102 static int __init sunsab_init(void)
1104 struct device_node *dp;
1105 int err;
1106 int num_channels = 0;
1108 for_each_node_by_name(dp, "se")
1109 num_channels += 2;
1110 for_each_node_by_name(dp, "serial") {
1111 if (of_device_is_compatible(dp, "sab82532"))
1112 num_channels += 2;
1115 if (num_channels) {
1116 sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
1117 num_channels, GFP_KERNEL);
1118 if (!sunsab_ports)
1119 return -ENOMEM;
1121 err = sunserial_register_minors(&sunsab_reg, num_channels);
1122 if (err) {
1123 kfree(sunsab_ports);
1124 sunsab_ports = NULL;
1126 return err;
1130 return of_register_driver(&sab_driver, &of_bus_type);
1133 static void __exit sunsab_exit(void)
1135 of_unregister_driver(&sab_driver);
1136 if (sunsab_reg.nr) {
1137 sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
1140 kfree(sunsab_ports);
1141 sunsab_ports = NULL;
1144 module_init(sunsab_init);
1145 module_exit(sunsab_exit);
1147 MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
1148 MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
1149 MODULE_LICENSE("GPL");