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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * linux/drivers/serial/s3c2410.c
  3  *
  4  * Driver for onboard UARTs on the Samsung S3C24XX
  5  *
  6  * Based on drivers/char/serial.c and drivers/char/21285.c
  7  *
  8  * Ben Dooks, (c) 2003 Simtec Electronics
  9  *
 10  * Changelog:
 11  *
 12  * 22-Jul-2004  BJD  Finished off device rewrite
 13  *
 14  * 21-Jul-2004  BJD  Thanks to <herbet@13thfloor.at> for pointing out
 15  *                   problems with baud rate and loss of IR settings. Update
 16  *                   to add configuration via platform_device structure
 17  *
 18  * 28-Sep-2004  BJD  Re-write for the following items
 19  *                   - S3C2410 and S3C2440 serial support
 20  *                   - Power Management support
 21  *                   - Fix console via IrDA devices
 22  *                   - SysReq (Herbert Pötzl)
 23  *                   - Break character handling (Herbert Pötzl)
 24  *                   - spin-lock initialisation (Dimitry Andric)
 25  *                   - added clock control
 26  *                   - updated init code to use platform_device info
 27 */
 28 
 29 /* Hote on 2410 error handling
 30  *
 31  * The s3c2410 manual has a love/hate affair with the contents of the
 32  * UERSTAT register in the UART blocks, and keeps marking some of the
 33  * error bits as reserved. Having checked with the s3c2410x01,
 34  * it copes with BREAKs properly, so I am happy to ignore the RESERVED
 35  * feature from the latter versions of the manual.
 36  *
 37  * If it becomes aparrent that latter versions of the 2410 remove these
 38  * bits, then action will have to be taken to differentiate the versions
 39  * and change the policy on BREAK
 40  *
 41  * BJD, 04-Nov-2004
 42 */
 43 
 44 #include <linux/config.h>
 45 
 46 #if defined(CONFIG_SERIAL_S3C2410_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 47 #define SUPPORT_SYSRQ
 48 #endif
 49 
 50 #include <linux/module.h>
 51 #include <linux/ioport.h>
 52 #include <linux/device.h>
 53 #include <linux/init.h>
 54 #include <linux/sysrq.h>
 55 #include <linux/console.h>
 56 #include <linux/tty.h>
 57 #include <linux/tty_flip.h>
 58 #include <linux/serial_core.h>
 59 #include <linux/serial.h>
 60 #include <linux/delay.h>
 61 
 62 #include <asm/io.h>
 63 #include <asm/irq.h>
 64 
 65 #include <asm/hardware.h>
 66 #include <asm/hardware/clock.h>
 67 
 68 #include <asm/arch/regs-serial.h>
 69 #include <asm/arch/regs-gpio.h>
 70 
 71 #include <asm/mach-types.h>
 72 
 73 /* structures */
 74 
 75 struct s3c24xx_uart_info {
 76         char                    *name;
 77         unsigned int            type;
 78         unsigned int            fifosize;
 79         unsigned long           rx_fifomask;
 80         unsigned long           rx_fifoshift;
 81         unsigned long           rx_fifofull;
 82         unsigned long           tx_fifomask;
 83         unsigned long           tx_fifoshift;
 84         unsigned long           tx_fifofull;
 85 
 86         /* clock source control */
 87 
 88         int (*get_clksrc)(struct uart_port *, struct s3c24xx_uart_clksrc *clk);
 89         int (*set_clksrc)(struct uart_port *, struct s3c24xx_uart_clksrc *clk);
 90 };
 91 
 92 struct s3c24xx_uart_port {
 93         unsigned char                   rx_claimed;
 94         unsigned char                   tx_claimed;
 95 
 96         struct s3c24xx_uart_info        *info;
 97         struct s3c24xx_uart_clksrc      *clksrc;
 98         struct clk                      *clk;
 99         struct clk                      *baudclk;
100         struct uart_port                port;
101 };
102 
103 
104 /* configuration defines */
105 
106 #if 0
107 #if 1
108 /* send debug to the low-level output routines */
109 
110 extern void printascii(const char *);
111 
112 static void
113 s3c24xx_serial_dbg(const char *fmt, ...)
114 {
115         va_list va;
116         char buff[256];
117 
118         va_start(va, fmt);
119         vsprintf(buff, fmt, va);
120         va_end(va);
121 
122         printascii(buff);
123 }
124 
125 #define dbg(x...) s3c24xx_serial_dbg(x)
126 
127 #else
128 #define dbg(x...) printk(KERN_DEBUG "s3c24xx: ");
129 #endif
130 #else /* no debug */
131 #define dbg(x...) do {} while(0)
132 #endif
133 
134 /* UART name and device definitions */
135 
136 #define S3C24XX_SERIAL_NAME     "ttySAC"
137 #define S3C24XX_SERIAL_DEVFS    "tts/"
138 #define S3C24XX_SERIAL_MAJOR    204
139 #define S3C24XX_SERIAL_MINOR    64
140 
141 
142 /* conversion functions */
143 
144 #define s3c24xx_dev_to_port(__dev) (struct uart_port *)dev_get_drvdata(__dev)
145 #define s3c24xx_dev_to_cfg(__dev) (struct s3c2410_uartcfg *)((__dev)->platform_data)
146 
147 /* we can support 3 uarts, but not always use them */
148 
149 #define NR_PORTS (3)
150 
151 /* port irq numbers */
152 
153 #define TX_IRQ(port) ((port)->irq + 1)
154 #define RX_IRQ(port) ((port)->irq)
155 
156 /* register access controls */
157 
158 #define portaddr(port, reg) ((port)->membase + (reg))
159 
160 #define rd_regb(port, reg) (__raw_readb(portaddr(port, reg)))
161 #define rd_regl(port, reg) (__raw_readl(portaddr(port, reg)))
162 
163 #define wr_regb(port, reg, val) \
164   do { __raw_writeb(val, portaddr(port, reg)); } while(0)
165 
166 #define wr_regl(port, reg, val) \
167   do { __raw_writel(val, portaddr(port, reg)); } while(0)
168 
169 /* macros to change one thing to another */
170 
171 #define tx_enabled(port) ((port)->unused[0])
172 #define rx_enabled(port) ((port)->unused[1])
173 
174 /* flag to ignore all characters comming in */
175 #define RXSTAT_DUMMY_READ (0x10000000)
176 
177 static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
178 {
179         return container_of(port, struct s3c24xx_uart_port, port);
180 }
181 
182 /* translate a port to the device name */
183 
184 static inline char *s3c24xx_serial_portname(struct uart_port *port)
185 {
186         return to_platform_device(port->dev)->name;
187 }
188 
189 static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
190 {
191         return (rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE);
192 }
193 
194 static void s3c24xx_serial_rx_enable(struct uart_port *port)
195 {
196         unsigned long flags;
197         unsigned int ucon, ufcon;
198         int count = 10000;
199 
200         spin_lock_irqsave(&port->lock, flags);
201 
202         while (--count && !s3c24xx_serial_txempty_nofifo(port))
203                 udelay(100);
204 
205         ufcon = rd_regl(port, S3C2410_UFCON);
206         ufcon |= S3C2410_UFCON_RESETRX;
207         wr_regl(port, S3C2410_UFCON, ufcon);
208 
209         ucon = rd_regl(port, S3C2410_UCON);
210         ucon |= S3C2410_UCON_RXIRQMODE;
211         wr_regl(port, S3C2410_UCON, ucon);
212 
213         rx_enabled(port) = 1;
214         spin_unlock_irqrestore(&port->lock, flags);
215 }
216 
217 static void s3c24xx_serial_rx_disable(struct uart_port *port)
218 {
219         unsigned long flags;
220         unsigned int ucon;
221 
222         spin_lock_irqsave(&port->lock, flags);
223 
224         ucon = rd_regl(port, S3C2410_UCON);
225         ucon &= ~S3C2410_UCON_RXIRQMODE;
226         wr_regl(port, S3C2410_UCON, ucon);
227 
228         rx_enabled(port) = 0;
229         spin_unlock_irqrestore(&port->lock, flags);
230 }
231 
232 static void
233 s3c24xx_serial_stop_tx(struct uart_port *port, unsigned int tty_stop)
234 {
235         if (tx_enabled(port)) {
236                 disable_irq(TX_IRQ(port));
237                 tx_enabled(port) = 0;
238                 if (port->flags & UPF_CONS_FLOW)
239                         s3c24xx_serial_rx_enable(port);
240         }
241 }
242 
243 static void
244 s3c24xx_serial_start_tx(struct uart_port *port, unsigned int tty_start)
245 {
246         if (!tx_enabled(port)) {
247                 if (port->flags & UPF_CONS_FLOW)
248                         s3c24xx_serial_rx_disable(port);
249 
250                 enable_irq(TX_IRQ(port));
251                 tx_enabled(port) = 1;
252         }
253 }
254 
255 
256 static void s3c24xx_serial_stop_rx(struct uart_port *port)
257 {
258         if (rx_enabled(port)) {
259                 dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
260                 disable_irq(RX_IRQ(port));
261                 rx_enabled(port) = 0;
262         }
263 }
264 
265 static void s3c24xx_serial_enable_ms(struct uart_port *port)
266 {
267 }
268 
269 static inline struct s3c24xx_uart_info *s3c24xx_port_to_info(struct uart_port *port)
270 {
271         return to_ourport(port)->info;
272 }
273 
274 static inline struct s3c2410_uartcfg *s3c24xx_port_to_cfg(struct uart_port *port)
275 {
276         if (port->dev == NULL)
277                 return NULL;
278 
279         return (struct s3c2410_uartcfg *)port->dev->platform_data;
280 }
281 
282 static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
283                                      unsigned long ufstat)
284 {
285         struct s3c24xx_uart_info *info = ourport->info;
286 
287         if (ufstat & info->rx_fifofull)
288                 return info->fifosize;
289 
290         return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
291 }
292 
293 
294 /* ? - where has parity gone?? */
295 #define S3C2410_UERSTAT_PARITY (0x1000)
296 
297 static irqreturn_t
298 s3c24xx_serial_rx_chars(int irq, void *dev_id, struct pt_regs *regs)
299 {
300         struct s3c24xx_uart_port *ourport = dev_id;
301         struct uart_port *port = &ourport->port;
302         struct tty_struct *tty = port->info->tty;
303         unsigned int ufcon, ch, flag, ufstat, uerstat;
304         int max_count = 64;
305 
306         while (max_count-- > 0) {
307                 ufcon = rd_regl(port, S3C2410_UFCON);
308                 ufstat = rd_regl(port, S3C2410_UFSTAT);
309 
310                 if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
311                         break;
312 
313                 if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
314                         if (tty->low_latency)
315                                 tty_flip_buffer_push(tty);
316 
317                         /*
318                          * If this failed then we will throw away the
319                          * bytes but must do so to clear interrupts
320                          */
321                 }
322 
323                 uerstat = rd_regl(port, S3C2410_UERSTAT);
324                 ch = rd_regb(port, S3C2410_URXH);
325 
326                 if (port->flags & UPF_CONS_FLOW) {
327                         int txe = s3c24xx_serial_txempty_nofifo(port);
328 
329                         if (rx_enabled(port)) {
330                                 if (!txe) {
331                                         rx_enabled(port) = 0;
332                                         continue;
333                                 }
334                         } else {
335                                 if (txe) {
336                                         ufcon |= S3C2410_UFCON_RESETRX;
337                                         wr_regl(port, S3C2410_UFCON, ufcon);
338                                         rx_enabled(port) = 1;
339                                         goto out;
340                                 }
341                                 continue;
342                         }
343                 }
344 
345                 /* insert the character into the buffer */
346 
347                 flag = TTY_NORMAL;
348                 port->icount.rx++;
349 
350                 if (uerstat & S3C2410_UERSTAT_ANY) {
351                         dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
352                             ch, uerstat);
353 
354                         /* check for break */
355                         if (uerstat & S3C2410_UERSTAT_BREAK) {
356                                 dbg("break!\n");
357                                 port->icount.brk++;
358                                 if (uart_handle_break(port))
359                                     goto ignore_char;
360                         }
361 
362                         if (uerstat & S3C2410_UERSTAT_FRAME)
363                                 port->icount.frame++;
364                         if (uerstat & S3C2410_UERSTAT_OVERRUN)
365                                 port->icount.overrun++;
366 
367                         uerstat &= port->read_status_mask;
368 
369                         if (uerstat & S3C2410_UERSTAT_BREAK)
370                                 flag = TTY_BREAK;
371                         else if (uerstat & S3C2410_UERSTAT_PARITY)
372                                 flag = TTY_PARITY;
373                         else if (uerstat & ( S3C2410_UERSTAT_FRAME | S3C2410_UERSTAT_OVERRUN))
374                                 flag = TTY_FRAME;
375                 }
376 
377                 if (uart_handle_sysrq_char(port, ch, regs))
378                         goto ignore_char;
379 
380                 if ((uerstat & port->ignore_status_mask) == 0) {
381                         tty_insert_flip_char(tty, ch, flag);
382                 }
383 
384                 if ((uerstat & S3C2410_UERSTAT_OVERRUN) &&
385                     tty->flip.count < TTY_FLIPBUF_SIZE) {
386                         /*
387                          * Overrun is special, since it's reported
388                          * immediately, and doesn't affect the current
389                          * character.
390                          */
391 
392                         tty_insert_flip_char(tty, 0, TTY_OVERRUN);
393                 }
394 
395         ignore_char:
396                 continue;
397         }
398         tty_flip_buffer_push(tty);
399 
400  out:
401         return IRQ_HANDLED;
402 }
403 
404 static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id, struct pt_regs *regs)
405 {
406         struct s3c24xx_uart_port *ourport = id;
407         struct uart_port *port = &ourport->port;
408         struct circ_buf *xmit = &port->info->xmit;
409         int count = 256;
410 
411         if (port->x_char) {
412                 wr_regb(port, S3C2410_UTXH, port->x_char);
413                 port->icount.tx++;
414                 port->x_char = 0;
415                 goto out;
416         }
417 
418         /* if there isnt anything more to transmit, or the uart is now
419          * stopped, disable the uart and exit
420         */
421 
422         if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
423                 s3c24xx_serial_stop_tx(port, 0);
424                 goto out;
425         }
426 
427         /* try and drain the buffer... */
428 
429         while (!uart_circ_empty(xmit) && count-- > 0) {
430                 if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
431                         break;
432 
433                 wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
434                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
435                 port->icount.tx++;
436         }
437 
438         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
439                 uart_write_wakeup(port);
440 
441         if (uart_circ_empty(xmit))
442                 s3c24xx_serial_stop_tx(port, 0);
443 
444  out:
445         return IRQ_HANDLED;
446 }
447 
448 static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
449 {
450         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
451         unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
452         unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
453 
454         if (ufcon & S3C2410_UFCON_FIFOMODE) {
455                 if ((ufstat & info->tx_fifomask) != 0 ||
456                     (ufstat & info->tx_fifofull))
457                         return 0;
458 
459                 return 1;
460         }
461 
462         return s3c24xx_serial_txempty_nofifo(port);
463 }
464 
465 /* no modem control lines */
466 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
467 {
468         unsigned int umstat = rd_regb(port,S3C2410_UMSTAT);
469 
470         if (umstat & S3C2410_UMSTAT_CTS)
471                 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
472         else
473                 return TIOCM_CAR | TIOCM_DSR;
474 }
475 
476 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
477 {
478         /* todo - possibly remove AFC and do manual CTS */
479 }
480 
481 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
482 {
483         unsigned long flags;
484         unsigned int ucon;
485 
486         spin_lock_irqsave(&port->lock, flags);
487 
488         ucon = rd_regl(port, S3C2410_UCON);
489 
490         if (break_state)
491                 ucon |= S3C2410_UCON_SBREAK;
492         else
493                 ucon &= ~S3C2410_UCON_SBREAK;
494 
495         wr_regl(port, S3C2410_UCON, ucon);
496 
497         spin_unlock_irqrestore(&port->lock, flags);
498 }
499 
500 static void s3c24xx_serial_shutdown(struct uart_port *port)
501 {
502         struct s3c24xx_uart_port *ourport = to_ourport(port);
503 
504         if (ourport->tx_claimed) {
505                 free_irq(TX_IRQ(port), ourport);
506                 tx_enabled(port) = 0;
507                 ourport->tx_claimed = 0;
508         }
509 
510         if (ourport->rx_claimed) {
511                 free_irq(RX_IRQ(port), ourport);
512                 ourport->rx_claimed = 0;
513                 rx_enabled(port) = 0;
514         }
515 }
516 
517 
518 static int s3c24xx_serial_startup(struct uart_port *port)
519 {
520         struct s3c24xx_uart_port *ourport = to_ourport(port);
521         unsigned long flags;
522         int ret;
523 
524         dbg("s3c24xx_serial_startup: port=%p (%08lx,%p)\n",
525             port->mapbase, port->membase);
526 
527         local_irq_save(flags);
528 
529         rx_enabled(port) = 1;
530 
531         ret = request_irq(RX_IRQ(port),
532                           s3c24xx_serial_rx_chars, 0,
533                           s3c24xx_serial_portname(port), ourport);
534 
535         if (ret != 0) {
536                 printk(KERN_ERR "cannot get irq %d\n", RX_IRQ(port));
537                 return ret;
538         }
539 
540         ourport->rx_claimed = 1;
541 
542         dbg("requesting tx irq...\n");
543 
544         tx_enabled(port) = 1;
545 
546         ret = request_irq(TX_IRQ(port),
547                           s3c24xx_serial_tx_chars, 0,
548                           s3c24xx_serial_portname(port), ourport);
549 
550         if (ret) {
551                 printk(KERN_ERR "cannot get irq %d\n", TX_IRQ(port));
552                 goto err;
553         }
554 
555         ourport->tx_claimed = 1;
556 
557         dbg("s3c24xx_serial_startup ok\n");
558 
559         /* the port reset code should have done the correct
560          * register setup for the port controls */
561 
562         local_irq_restore(flags);
563         return ret;
564 
565  err:
566         s3c24xx_serial_shutdown(port);
567         local_irq_restore(flags);
568         return ret;
569 }
570 
571 /* power power management control */
572 
573 static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
574                               unsigned int old)
575 {
576         struct s3c24xx_uart_port *ourport = to_ourport(port);
577 
578         switch (level) {
579         case 3:
580                 if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL)
581                         clk_disable(ourport->baudclk);
582 
583                 clk_disable(ourport->clk);
584                 break;
585 
586         case 0:
587                 clk_enable(ourport->clk);
588 
589                 if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL)
590                         clk_enable(ourport->baudclk);
591 
592                 break;
593         default:
594                 printk(KERN_ERR "s3c24xx_serial: unknown pm %d\n", level);
595         }
596 }
597 
598 /* baud rate calculation
599  *
600  * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
601  * of different sources, including the peripheral clock ("pclk") and an
602  * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
603  * with a programmable extra divisor.
604  *
605  * The following code goes through the clock sources, and calculates the
606  * baud clocks (and the resultant actual baud rates) and then tries to
607  * pick the closest one and select that.
608  *
609  * NOTES:
610  *      1) there is no current code to properly select/deselect FCLK on
611  *         the s3c2440, so only specify FCLK or non-FCLK in the clock
612  *         sources for the UART
613  *
614 */
615 
616 
617 #define MAX_CLKS (8)
618 
619 static struct s3c24xx_uart_clksrc tmp_clksrc = {
620         .name           = "pclk",
621         .min_baud       = 0,
622         .max_baud       = 0,
623         .divisor        = 1,
624 };
625 
626 static inline int
627 s3c24xx_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c)
628 {
629         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
630 
631         return (info->get_clksrc)(port, c);
632 }
633 
634 static inline int
635 s3c24xx_serial_setsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c)
636 {
637         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
638 
639         return (info->set_clksrc)(port, c);
640 }
641 
642 struct baud_calc {
643         struct s3c24xx_uart_clksrc      *clksrc;
644         unsigned int                     calc;
645         unsigned int                     quot;
646         struct clk                      *src;
647 };
648 
649 static int s3c24xx_serial_calcbaud(struct baud_calc *calc,
650                                    struct uart_port *port,
651                                    struct s3c24xx_uart_clksrc *clksrc,
652                                    unsigned int baud)
653 {
654         unsigned long rate;
655 
656         calc->src = clk_get(port->dev, clksrc->name);
657         if (calc->src == NULL || IS_ERR(calc->src))
658                 return 0;
659 
660         rate = clk_get_rate(calc->src);
661 
662         calc->clksrc = clksrc;
663         calc->quot = (rate + (8 * baud)) / (16 * baud);
664         calc->calc = (rate / (calc->quot * 16));
665 
666         calc->quot--;
667         return 1;
668 }
669 
670 static unsigned int s3c24xx_serial_getclk(struct uart_port *port,
671                                           struct s3c24xx_uart_clksrc **clksrc,
672                                           struct clk **clk,
673                                           unsigned int baud)
674 {
675         struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
676         struct s3c24xx_uart_clksrc *clkp;
677         struct baud_calc res[MAX_CLKS];
678         struct baud_calc *resptr, *best, *sptr;
679         int i;
680 
681         clkp = cfg->clocks;
682         best = NULL;
683 
684         if (cfg->clocks_size < 2) {
685                 if (cfg->clocks_size == 0)
686                         clkp = &tmp_clksrc;
687 
688                 s3c24xx_serial_calcbaud(res, port, clkp, baud);
689                 best = res;
690                 resptr = best + 1;
691         } else {
692                 resptr = res;
693 
694                 for (i = 0; i < cfg->clocks_size; i++, clkp++) {
695                         if (s3c24xx_serial_calcbaud(resptr, port, clkp, baud))
696                                 resptr++;
697                 }
698         }
699 
700         /* ok, we now need to select the best clock we found */
701 
702         if (!best) {
703                 unsigned int deviation = (1<<30)|((1<<30)-1);
704                 int calc_deviation;
705 
706                 for (sptr = res; sptr < resptr; sptr++) {
707                         printk(KERN_DEBUG
708                                "found clk %p (%s) quot %d, calc %d\n",
709                                sptr->clksrc, sptr->clksrc->name,
710                                sptr->quot, sptr->calc);
711 
712                         calc_deviation = baud - sptr->calc;
713                         if (calc_deviation < 0)
714                                 calc_deviation = -calc_deviation;
715 
716                         if (calc_deviation < deviation) {
717                                 best = sptr;
718                                 deviation = calc_deviation;
719                         }
720                 }
721 
722                 printk(KERN_DEBUG "best %p (deviation %d)\n", best, deviation);
723         }
724 
725         printk(KERN_DEBUG "selected clock %p (%s) quot %d, calc %d\n",
726                best->clksrc, best->clksrc->name, best->quot, best->calc);
727 
728         /* store results to pass back */
729 
730         *clksrc = best->clksrc;
731         *clk    = best->src;
732 
733         return best->quot;
734 }
735 
736 static void s3c24xx_serial_set_termios(struct uart_port *port,
737                                        struct termios *termios,
738                                        struct termios *old)
739 {
740         struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
741         struct s3c24xx_uart_port *ourport = to_ourport(port);
742         struct s3c24xx_uart_clksrc *clksrc;
743         struct clk *clk;
744         unsigned long flags;
745         unsigned int baud, quot;
746         unsigned int ulcon;
747         unsigned int umcon;
748 
749         /*
750          * We don't support modem control lines.
751          */
752         termios->c_cflag &= ~(HUPCL | CMSPAR);
753         termios->c_cflag |= CLOCAL;
754 
755         /*
756          * Ask the core to calculate the divisor for us.
757          */
758 
759         baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
760 
761         if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
762                 quot = port->custom_divisor;
763         else
764                 quot = s3c24xx_serial_getclk(port, &clksrc, &clk, baud);
765 
766         /* check to see if we need  to change clock source */
767 
768         if (ourport->clksrc != clksrc || ourport->baudclk != clk) {
769                 s3c24xx_serial_setsource(port, clksrc);
770 
771                 if (ourport->baudclk != NULL && !IS_ERR(ourport->baudclk)) {
772                         clk_disable(ourport->baudclk);
773                         clk_unuse(ourport->baudclk);
774                         ourport->baudclk  = NULL;
775                 }
776 
777                 clk_use(clk);
778                 clk_enable(clk);
779 
780                 ourport->clksrc = clksrc;
781                 ourport->baudclk = clk;
782         }
783 
784         switch (termios->c_cflag & CSIZE) {
785         case CS5:
786                 dbg("config: 5bits/char\n");
787                 ulcon = S3C2410_LCON_CS5;
788                 break;
789         case CS6:
790                 dbg("config: 6bits/char\n");
791                 ulcon = S3C2410_LCON_CS6;
792                 break;
793         case CS7:
794                 dbg("config: 7bits/char\n");
795                 ulcon = S3C2410_LCON_CS7;
796                 break;
797         case CS8:
798         default:
799                 dbg("config: 8bits/char\n");
800                 ulcon = S3C2410_LCON_CS8;
801                 break;
802         }
803 
804         /* preserve original lcon IR settings */
805         ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
806 
807         if (termios->c_cflag & CSTOPB)
808                 ulcon |= S3C2410_LCON_STOPB;
809 
810         umcon = (termios->c_cflag & CRTSCTS) ? S3C2410_UMCOM_AFC : 0;
811 
812         if (termios->c_cflag & PARENB) {
813                 if (termios->c_cflag & PARODD)
814                         ulcon |= S3C2410_LCON_PODD;
815                 else
816                         ulcon |= S3C2410_LCON_PEVEN;
817         } else {
818                 ulcon |= S3C2410_LCON_PNONE;
819         }
820 
821         spin_lock_irqsave(&port->lock, flags);
822 
823         dbg("setting ulcon to %08x, brddiv to %d\n", ulcon, quot);
824 
825         wr_regl(port, S3C2410_ULCON, ulcon);
826         wr_regl(port, S3C2410_UBRDIV, quot);
827         wr_regl(port, S3C2410_UMCON, umcon);
828 
829         dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
830             rd_regl(port, S3C2410_ULCON),
831             rd_regl(port, S3C2410_UCON),
832             rd_regl(port, S3C2410_UFCON));
833 
834         /*
835          * Update the per-port timeout.
836          */
837         uart_update_timeout(port, termios->c_cflag, baud);
838 
839         /*
840          * Which character status flags are we interested in?
841          */
842         port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
843         if (termios->c_iflag & INPCK)
844                 port->read_status_mask |= S3C2410_UERSTAT_FRAME | S3C2410_UERSTAT_PARITY;
845 
846         /*
847          * Which character status flags should we ignore?
848          */
849         port->ignore_status_mask = 0;
850         if (termios->c_iflag & IGNPAR)
851                 port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
852         if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
853                 port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
854 
855         /*
856          * Ignore all characters if CREAD is not set.
857          */
858         if ((termios->c_cflag & CREAD) == 0)
859                 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
860 
861         spin_unlock_irqrestore(&port->lock, flags);
862 }
863 
864 static const char *s3c24xx_serial_type(struct uart_port *port)
865 {
866         switch (port->type) {
867         case PORT_S3C2410:
868                 return "S3C2410";
869         case PORT_S3C2440:
870                 return "S3C2440";
871         default:
872                 return NULL;
873         }
874 }
875 
876 #define MAP_SIZE (0x100)
877 
878 static void s3c24xx_serial_release_port(struct uart_port *port)
879 {
880         release_mem_region(port->mapbase, MAP_SIZE);
881 }
882 
883 static int s3c24xx_serial_request_port(struct uart_port *port)
884 {
885         char *name = s3c24xx_serial_portname(port);
886         return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY;
887 }
888 
889 static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
890 {
891         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
892 
893         if (flags & UART_CONFIG_TYPE &&
894             s3c24xx_serial_request_port(port) == 0)
895                 port->type = info->type;
896 }
897 
898 /*
899  * verify the new serial_struct (for TIOCSSERIAL).
900  */
901 static int
902 s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
903 {
904         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
905 
906         if (ser->type != PORT_UNKNOWN && ser->type != info->type)
907                 return -EINVAL;
908 
909         return 0;
910 }
911 
912 
913 #ifdef CONFIG_SERIAL_S3C2410_CONSOLE
914 
915 static struct console s3c24xx_serial_console;
916 
917 #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
918 #else
919 #define S3C24XX_SERIAL_CONSOLE NULL
920 #endif
921 
922 static struct uart_ops s3c24xx_serial_ops = {
923         .pm             = s3c24xx_serial_pm,
924         .tx_empty       = s3c24xx_serial_tx_empty,
925         .get_mctrl      = s3c24xx_serial_get_mctrl,
926         .set_mctrl      = s3c24xx_serial_set_mctrl,
927         .stop_tx        = s3c24xx_serial_stop_tx,
928         .start_tx       = s3c24xx_serial_start_tx,
929         .stop_rx        = s3c24xx_serial_stop_rx,
930         .enable_ms      = s3c24xx_serial_enable_ms,
931         .break_ctl      = s3c24xx_serial_break_ctl,
932         .startup        = s3c24xx_serial_startup,
933         .shutdown       = s3c24xx_serial_shutdown,
934         .set_termios    = s3c24xx_serial_set_termios,
935         .type           = s3c24xx_serial_type,
936         .release_port   = s3c24xx_serial_release_port,
937         .request_port   = s3c24xx_serial_request_port,
938         .config_port    = s3c24xx_serial_config_port,
939         .verify_port    = s3c24xx_serial_verify_port,
940 };
941 
942 
943 static struct uart_driver s3c24xx_uart_drv = {
944         .owner          = THIS_MODULE,
945         .dev_name       = "s3c2410_serial",
946         .nr             = 3,
947         .cons           = S3C24XX_SERIAL_CONSOLE,
948         .driver_name    = S3C24XX_SERIAL_NAME,
949         .devfs_name     = S3C24XX_SERIAL_DEVFS,
950         .major          = S3C24XX_SERIAL_MAJOR,
951         .minor          = S3C24XX_SERIAL_MINOR,
952 };
953 
954 static struct s3c24xx_uart_port s3c24xx_serial_ports[NR_PORTS] = {
955         [0] = {
956                 .port = {
957                         .lock           = SPIN_LOCK_UNLOCKED,
958                         .membase        = 0,
959                         .mapbase        = 0,
960                         .iotype         = UPIO_MEM,
961                         .irq            = IRQ_S3CUART_RX0,
962                         .uartclk        = 0,
963                         .fifosize       = 16,
964                         .ops            = &s3c24xx_serial_ops,
965                         .flags          = UPF_BOOT_AUTOCONF,
966                         .line           = 0,
967                 }
968         },
969         [1] = {
970                 .port = {
971                         .lock           = SPIN_LOCK_UNLOCKED,
972                         .membase        = 0,
973                         .mapbase        = 0,
974                         .iotype         = UPIO_MEM,
975                         .irq            = IRQ_S3CUART_RX1,
976                         .uartclk        = 0,
977                         .fifosize       = 16,
978                         .ops            = &s3c24xx_serial_ops,
979                         .flags          = UPF_BOOT_AUTOCONF,
980                         .line           = 1,
981                 }
982         },
983 #if NR_PORTS > 2
984 
985         [2] = {
986                 .port = {
987                         .lock           = SPIN_LOCK_UNLOCKED,
988                         .membase        = 0,
989                         .mapbase        = 0,
990                         .iotype         = UPIO_MEM,
991                         .irq            = IRQ_S3CUART_RX2,
992                         .uartclk        = 0,
993                         .fifosize       = 16,
994                         .ops            = &s3c24xx_serial_ops,
995                         .flags          = UPF_BOOT_AUTOCONF,
996                         .line           = 2,
997                 }
998         }
999 #endif
1000 };
1001 
1002 
1003 static int s3c24xx_serial_resetport(struct uart_port *port,
1004                                     struct s3c2410_uartcfg *cfg)
1005 {
1006         /* ensure registers are setup */
1007 
1008         dbg("s3c24xx_serial_resetport: port=%p (%08lx), cfg=%p\n",
1009             port, port->mapbase, cfg);
1010 
1011         wr_regl(port, S3C2410_UCON,  cfg->ucon);
1012         wr_regl(port, S3C2410_ULCON, cfg->ulcon);
1013 
1014         /* reset both fifos */
1015 
1016         wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
1017         wr_regl(port, S3C2410_UFCON, cfg->ufcon);
1018 
1019         return 0;
1020 }
1021 
1022 /* s3c24xx_serial_init_port
1023  *
1024  * initialise a single serial port from the platform device given
1025  */
1026 
1027 static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
1028                                     struct s3c24xx_uart_info *info,
1029                                     struct platform_device *platdev)
1030 {
1031         struct uart_port *port = &ourport->port;
1032         struct s3c2410_uartcfg *cfg;
1033         struct resource *res;
1034 
1035         dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev);
1036 
1037         if (platdev == NULL)
1038                 return -ENODEV;
1039 
1040         cfg = s3c24xx_dev_to_cfg(&platdev->dev);
1041 
1042         if (port->mapbase != 0)
1043                 return 0;
1044 
1045         if (cfg->hwport > 3)
1046                 return -EINVAL;
1047 
1048         /* setup info for port */
1049         port->dev       = &platdev->dev;
1050         ourport->info   = info;
1051 
1052         /* copy the info in from provided structure */
1053         ourport->port.fifosize = info->fifosize;
1054 
1055         dbg("s3c24xx_serial_init_port: %p (hw %d)...\n", port, cfg->hwport);
1056 
1057         port->uartclk = 1;
1058 
1059         if (cfg->uart_flags & UPF_CONS_FLOW) {
1060                 dbg("s3c24xx_serial_init_port: enabling flow control\n");
1061                 port->flags |= UPF_CONS_FLOW;
1062         }
1063 
1064         /* sort our the physical and virtual addresses for each UART */
1065 
1066         res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
1067         if (res == NULL) {
1068                 printk(KERN_ERR "failed to find memory resource for uart\n");
1069                 return -EINVAL;
1070         }
1071 
1072         dbg("resource %p (%lx..%lx)\n", res, res->start, res->end);
1073 
1074         port->mapbase   = res->start;
1075         port->membase   = (void __iomem *)(res->start - S3C2410_PA_UART);
1076         port->membase  += S3C2410_VA_UART;
1077         port->irq       = platform_get_irq(platdev, 0);
1078 
1079         ourport->clk    = clk_get(&platdev->dev, "uart");
1080 
1081         if (ourport->clk != NULL && !IS_ERR(ourport->clk))
1082                 clk_use(ourport->clk);
1083 
1084         dbg("port: map=%08x, mem=%08x, irq=%d, clock=%ld\n",
1085             port->mapbase, port->membase, port->irq, port->uartclk);
1086 
1087         /* reset the fifos (and setup the uart) */
1088         s3c24xx_serial_resetport(port, cfg);
1089         return 0;
1090 }
1091 
1092 /* Device driver serial port probe */
1093 
1094 static int probe_index = 0;
1095 
1096 int s3c24xx_serial_probe(struct device *_dev,
1097                          struct s3c24xx_uart_info *info)
1098 {
1099         struct s3c24xx_uart_port *ourport;
1100         struct platform_device *dev = to_platform_device(_dev);
1101         int ret;
1102 
1103         dbg("s3c24xx_serial_probe(%p, %p) %d\n", _dev, info, probe_index);
1104 
1105         ourport = &s3c24xx_serial_ports[probe_index];
1106         probe_index++;
1107 
1108         dbg("%s: initialising port %p...\n", __FUNCTION__, ourport);
1109 
1110         ret = s3c24xx_serial_init_port(ourport, info, dev);
1111         if (ret < 0)
1112                 goto probe_err;
1113 
1114         dbg("%s: adding port\n", __FUNCTION__);
1115         uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
1116         dev_set_drvdata(_dev, &ourport->port);
1117 
1118         return 0;
1119 
1120  probe_err:
1121         return ret;
1122 }
1123 
1124 int s3c24xx_serial_remove(struct device *_dev)
1125 {
1126         struct uart_port *port = s3c24xx_dev_to_port(_dev);
1127 
1128         if (port)
1129                 uart_remove_one_port(&s3c24xx_uart_drv, port);
1130 
1131         return 0;
1132 }
1133 
1134 /* UART power management code */
1135 
1136 #ifdef CONFIG_PM
1137 
1138 int s3c24xx_serial_suspend(struct device *dev, u32 state, u32 level)
1139 {
1140         struct uart_port *port = s3c24xx_dev_to_port(dev);
1141 
1142         if (port && level == SUSPEND_DISABLE)
1143                 uart_suspend_port(&s3c24xx_uart_drv, port);
1144 
1145         return 0;
1146 }
1147 
1148 int s3c24xx_serial_resume(struct device *dev, u32 level)
1149 {
1150         struct uart_port *port = s3c24xx_dev_to_port(dev);
1151         struct s3c24xx_uart_port *ourport = to_ourport(port);
1152 
1153         if (port && level == RESUME_ENABLE) {
1154                 clk_enable(ourport->clk);
1155                 s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
1156                 clk_disable(ourport->clk);
1157 
1158                 uart_resume_port(&s3c24xx_uart_drv, port);
1159         }
1160 
1161         return 0;
1162 }
1163 
1164 #else
1165 #define s3c24xx_serial_suspend NULL
1166 #define s3c24xx_serial_resume  NULL
1167 #endif
1168 
1169 int s3c24xx_serial_init(struct device_driver *drv,
1170                         struct s3c24xx_uart_info *info)
1171 {
1172         dbg("s3c24xx_serial_init(%p,%p)\n", drv, info);
1173         return driver_register(drv);
1174 }
1175 
1176 
1177 /* now comes the code to initialise either the s3c2410 or s3c2440 serial
1178  * port information
1179 */
1180 
1181 /* cpu specific variations on the serial port support */
1182 
1183 #ifdef CONFIG_CPU_S3C2410
1184 
1185 static int s3c2410_serial_setsource(struct uart_port *port,
1186                                     struct s3c24xx_uart_clksrc *clk)
1187 {
1188         unsigned long ucon = rd_regl(port, S3C2410_UCON);
1189 
1190         if (strcmp(clk->name, "uclk") == 0)
1191                 ucon |= S3C2410_UCON_UCLK;
1192         else
1193                 ucon &= ~S3C2410_UCON_UCLK;
1194 
1195         wr_regl(port, S3C2410_UCON, ucon);
1196         return 0;
1197 }
1198 
1199 static int s3c2410_serial_getsource(struct uart_port *port,
1200                                     struct s3c24xx_uart_clksrc *clk)
1201 {
1202         unsigned long ucon = rd_regl(port, S3C2410_UCON);
1203 
1204         clk->divisor = 1;
1205         clk->name = (ucon & S3C2410_UCON_UCLK) ? "uclk" : "pclk";
1206 
1207         return 0;
1208 }
1209 
1210 static struct s3c24xx_uart_info s3c2410_uart_inf = {
1211         .name           = "Samsung S3C2410 UART",
1212         .type           = PORT_S3C2410,
1213         .fifosize       = 16,
1214         .rx_fifomask    = S3C2410_UFSTAT_RXMASK,
1215         .rx_fifoshift   = S3C2410_UFSTAT_RXSHIFT,
1216         .rx_fifofull    = S3C2410_UFSTAT_RXFULL,
1217         .tx_fifofull    = S3C2410_UFSTAT_TXFULL,
1218         .tx_fifomask    = S3C2410_UFSTAT_TXMASK,
1219         .tx_fifoshift   = S3C2410_UFSTAT_TXSHIFT,
1220         .get_clksrc     = s3c2410_serial_getsource,
1221         .set_clksrc     = s3c2410_serial_setsource,
1222 };
1223 
1224 /* device management */
1225 
1226 static int s3c2410_serial_probe(struct device *dev)
1227 {
1228         return s3c24xx_serial_probe(dev, &s3c2410_uart_inf);
1229 }
1230 
1231 static struct device_driver s3c2410_serial_drv = {
1232         .name           = "s3c2410-uart",
1233         .bus            = &platform_bus_type,
1234         .probe          = s3c2410_serial_probe,
1235         .remove         = s3c24xx_serial_remove,
1236         .suspend        = s3c24xx_serial_suspend,
1237         .resume         = s3c24xx_serial_resume,
1238 };
1239 
1240 static inline int s3c2410_serial_init(void)
1241 {
1242         return s3c24xx_serial_init(&s3c2410_serial_drv, &s3c2410_uart_inf);
1243 }
1244 
1245 static inline void s3c2410_serial_exit(void)
1246 {
1247         driver_unregister(&s3c2410_serial_drv);
1248 }
1249 
1250 #define s3c2410_uart_inf_at &s3c2410_uart_inf
1251 #else
1252 
1253 static inline int s3c2410_serial_init(void)
1254 {
1255         return 0;
1256 }
1257 
1258 static inline void s3c2410_serial_exit(void)
1259 {
1260 }
1261 
1262 #define s3c2410_uart_inf_at NULL
1263 
1264 #endif /* CONFIG_CPU_S3C2410 */
1265 
1266 #ifdef CONFIG_CPU_S3C2440
1267 
1268 static int s3c2440_serial_setsource(struct uart_port *port,
1269                                      struct s3c24xx_uart_clksrc *clk)
1270 {
1271         unsigned long ucon = rd_regl(port, S3C2410_UCON);
1272 
1273         // todo - proper fclk<>nonfclk switch //
1274 
1275         ucon &= ~S3C2440_UCON_CLKMASK;
1276 
1277         if (strcmp(clk->name, "uclk") == 0)
1278                 ucon |= S3C2440_UCON_UCLK;
1279         else if (strcmp(clk->name, "pclk") == 0)
1280                 ucon |= S3C2440_UCON_PCLK;
1281         else if (strcmp(clk->name, "fclk") == 0)
1282                 ucon |= S3C2440_UCON_FCLK;
1283         else {
1284                 printk(KERN_ERR "unknown clock source %s\n", clk->name);
1285                 return -EINVAL;
1286         }
1287 
1288         wr_regl(port, S3C2410_UCON, ucon);
1289         return 0;
1290 }
1291 
1292 
1293 static int s3c2440_serial_getsource(struct uart_port *port,
1294                                     struct s3c24xx_uart_clksrc *clk)
1295 {
1296         unsigned long ucon = rd_regl(port, S3C2410_UCON);
1297 
1298         switch (ucon & S3C2440_UCON_CLKMASK) {
1299         case S3C2440_UCON_UCLK:
1300                 clk->divisor = 1;
1301                 clk->name = "uclk";
1302                 break;
1303 
1304         case S3C2440_UCON_PCLK:
1305         case S3C2440_UCON_PCLK2:
1306                 clk->divisor = 1;
1307                 clk->name = "pclk";
1308                 break;
1309 
1310         case S3C2440_UCON_FCLK:
1311                 clk->divisor = 7; /* todo - work out divisor */
1312                 clk->name = "fclk";
1313                 break;
1314         }
1315 
1316         return 0;
1317 }
1318 
1319 
1320 static struct s3c24xx_uart_info s3c2440_uart_inf = {
1321         .name           = "Samsung S3C2440 UART",
1322         .type           = PORT_S3C2440,
1323         .fifosize       = 64,
1324         .rx_fifomask    = S3C2440_UFSTAT_RXMASK,
1325         .rx_fifoshift   = S3C2440_UFSTAT_RXSHIFT,
1326         .rx_fifofull    = S3C2440_UFSTAT_RXFULL,
1327         .tx_fifofull    = S3C2440_UFSTAT_TXFULL,
1328         .tx_fifomask    = S3C2440_UFSTAT_TXMASK,
1329         .tx_fifoshift   = S3C2440_UFSTAT_TXSHIFT,
1330         .get_clksrc     = s3c2440_serial_getsource,
1331         .set_clksrc     = s3c2440_serial_setsource
1332 };
1333 
1334 /* device management */
1335 
1336 static int s3c2440_serial_probe(struct device *dev)
1337 {
1338         dbg("s3c2440_serial_probe: dev=%p\n", dev);
1339         return s3c24xx_serial_probe(dev, &s3c2440_uart_inf);
1340 }
1341 
1342 static struct device_driver s3c2440_serial_drv = {
1343         .name           = "s3c2440-uart",
1344         .bus            = &platform_bus_type,
1345         .probe          = s3c2440_serial_probe,
1346         .remove         = s3c24xx_serial_remove,
1347         .suspend        = s3c24xx_serial_suspend,
1348         .resume         = s3c24xx_serial_resume,
1349 };
1350 
1351 
1352 static inline int s3c2440_serial_init(void)
1353 {
1354         return s3c24xx_serial_init(&s3c2440_serial_drv, &s3c2440_uart_inf);
1355 }
1356 
1357 static inline void s3c2440_serial_exit(void)
1358 {
1359         driver_unregister(&s3c2440_serial_drv);
1360 }
1361 
1362 #define s3c2440_uart_inf_at &s3c2440_uart_inf
1363 #else
1364 
1365 static inline int s3c2440_serial_init(void)
1366 {
1367         return 0;
1368 }
1369 
1370 static inline void s3c2440_serial_exit(void)
1371 {
1372 }
1373 
1374 #define s3c2440_uart_inf_at NULL
1375 #endif /* CONFIG_CPU_S3C2440 */
1376 
1377 /* module initialisation code */
1378 
1379 static int __init s3c24xx_serial_modinit(void)
1380 {
1381         int ret;
1382 
1383         ret = uart_register_driver(&s3c24xx_uart_drv);
1384         if (ret < 0) {
1385                 printk(KERN_ERR "failed to register UART driver\n");
1386                 return -1;
1387         }
1388 
1389         s3c2410_serial_init();
1390         s3c2440_serial_init();
1391 
1392         return 0;
1393 }
1394 
1395 static void __exit s3c24xx_serial_modexit(void)
1396 {
1397         s3c2410_serial_exit();
1398         s3c2440_serial_exit();
1399 
1400         uart_unregister_driver(&s3c24xx_uart_drv);
1401 }
1402 
1403 
1404 module_init(s3c24xx_serial_modinit);
1405 module_exit(s3c24xx_serial_modexit);
1406 
1407 /* Console code */
1408 
1409 #ifdef CONFIG_SERIAL_S3C2410_CONSOLE
1410 
1411 static struct uart_port *cons_uart;
1412 
1413 static int
1414 s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
1415 {
1416         struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1417         unsigned long ufstat, utrstat;
1418 
1419         if (ufcon & S3C2410_UFCON_FIFOMODE) {
1420                 /* fifo mode - check ammount of data in fifo registers... */
1421 
1422                 ufstat = rd_regl(port, S3C2410_UFSTAT);
1423                 return (ufstat & info->tx_fifofull) ? 0 : 1;
1424         }
1425 
1426         /* in non-fifo mode, we go and use the tx buffer empty */
1427 
1428         utrstat = rd_regl(port, S3C2410_UTRSTAT);
1429         return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
1430 }
1431 
1432 static void
1433 s3c24xx_serial_console_write(struct console *co, const char *s,
1434                              unsigned int count)
1435 {
1436         int i;
1437         unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
1438 
1439         for (i = 0; i < count; i++) {
1440                 while (!s3c24xx_serial_console_txrdy(cons_uart, ufcon))
1441                         barrier();
1442 
1443                 wr_regb(cons_uart, S3C2410_UTXH, s[i]);
1444 
1445                 if (s[i] == '\n') {
1446                         while (!s3c24xx_serial_console_txrdy(cons_uart, ufcon))
1447                                 barrier();
1448 
1449                         wr_regb(cons_uart, S3C2410_UTXH, '\r');
1450                 }
1451         }
1452 }
1453 
1454 static void __init
1455 s3c24xx_serial_get_options(struct uart_port *port, int *baud,
1456                            int *parity, int *bits)
1457 {
1458         struct s3c24xx_uart_clksrc clksrc;
1459         struct clk *clk;
1460         unsigned int ulcon;
1461         unsigned int ucon;
1462         unsigned int ubrdiv;
1463         unsigned long rate;
1464 
1465         ulcon  = rd_regl(port, S3C2410_ULCON);
1466         ucon   = rd_regl(port, S3C2410_UCON);
1467         ubrdiv = rd_regl(port, S3C2410_UBRDIV);
1468 
1469         dbg("s3c24xx_serial_get_options: port=%p\n"
1470             "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
1471             port, ulcon, ucon, ubrdiv);
1472 
1473         if ((ucon & 0xf) != 0) {
1474                 /* consider the serial port configured if the tx/rx mode set */
1475 
1476                 switch (ulcon & S3C2410_LCON_CSMASK) {
1477                 case S3C2410_LCON_CS5:
1478                         *bits = 5;
1479                         break;
1480                 case S3C2410_LCON_CS6:
1481                         *bits = 6;
1482                         break;
1483                 case S3C2410_LCON_CS7:
1484                         *bits = 7;
1485                         break;
1486                 default:
1487                 case S3C2410_LCON_CS8:
1488                         *bits = 8;
1489                         break;
1490                 }
1491 
1492                 switch (ulcon & S3C2410_LCON_PMASK) {
1493                 case S3C2410_LCON_PEVEN:
1494                         *parity = 'e';
1495                         break;
1496 
1497                 case S3C2410_LCON_PODD:
1498                         *parity = 'o';
1499                         break;
1500 
1501                 case S3C2410_LCON_PNONE:
1502                 default:
1503                         *parity = 'n';
1504                 }
1505 
1506                 /* now calculate the baud rate */
1507 
1508                 s3c24xx_serial_getsource(port, &clksrc);
1509 
1510                 clk = clk_get(port->dev, clksrc.name);
1511                 if (!IS_ERR(clk) && clk != NULL)
1512                         rate = clk_get_rate(clk);
1513                 else
1514                         rate = 1;
1515 
1516 
1517                 *baud = rate / ( 16 * (ubrdiv + 1));
1518                 dbg("calculated baud %d\n", *baud);
1519         }
1520 
1521 }
1522 
1523 /* s3c24xx_serial_init_ports
1524  *
1525  * initialise the serial ports from the machine provided initialisation
1526  * data.
1527 */
1528 
1529 static int s3c24xx_serial_init_ports(struct s3c24xx_uart_info *info)
1530 {
1531         struct s3c24xx_uart_port *ptr = s3c24xx_serial_ports;
1532         struct platform_device **platdev_ptr;
1533         int i;
1534 
1535         dbg("s3c24xx_serial_init_ports: initialising ports...\n");
1536 
1537         platdev_ptr = s3c24xx_uart_devs;
1538 
1539         for (i = 0; i < NR_PORTS; i++, ptr++, platdev_ptr++) {
1540                 s3c24xx_serial_init_port(ptr, info, *platdev_ptr);
1541         }
1542 
1543         return 0;
1544 }
1545 
1546 static int __init
1547 s3c24xx_serial_console_setup(struct console *co, char *options)
1548 {
1549         struct uart_port *port;
1550         int baud = 9600;
1551         int bits = 8;
1552         int parity = 'n';
1553         int flow = 'n';
1554 
1555         dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
1556             co, co->index, options);
1557 
1558         /* is this a valid port */
1559 
1560         if (co->index == -1 || co->index >= NR_PORTS)
1561                 co->index = 0;
1562 
1563         port = &s3c24xx_serial_ports[co->index].port;
1564 
1565         /* is the port configured? */
1566 
1567         if (port->mapbase == 0x0) {
1568                 co->index = 0;
1569                 port = &s3c24xx_serial_ports[co->index].port;
1570         }
1571 
1572         cons_uart = port;
1573 
1574         dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
1575 
1576         /*
1577          * Check whether an invalid uart number has been specified, and
1578          * if so, search for the first available port that does have
1579          * console support.
1580          */
1581         if (options)
1582                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1583         else
1584                 s3c24xx_serial_get_options(port, &baud, &parity, &bits);
1585 
1586         dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
1587 
1588         return uart_set_options(port, co, baud, parity, bits, flow);
1589 }
1590 
1591 /* s3c24xx_serial_initconsole
1592  *
1593  * initialise the console from one of the uart drivers
1594 */
1595 
1596 static struct console s3c24xx_serial_console =
1597 {
1598         .name           = S3C24XX_SERIAL_NAME,
1599         .device         = uart_console_device,
1600         .flags          = CON_PRINTBUFFER,
1601         .index          = -1,
1602         .write          = s3c24xx_serial_console_write,
1603         .setup          = s3c24xx_serial_console_setup
1604 };
1605 
1606 
1607 static int s3c24xx_serial_initconsole(void)
1608 {
1609         struct s3c24xx_uart_info *info;
1610         struct platform_device *dev = s3c24xx_uart_devs[0];
1611 
1612         dbg("s3c24xx_serial_initconsole\n");
1613 
1614         /* select driver based on the cpu */
1615 
1616         if (dev == NULL) {
1617                 printk(KERN_ERR "s3c24xx: no devices for console init\n");
1618                 return 0;
1619         }
1620 
1621         if (strcmp(dev->name, "s3c2410-uart") == 0) {
1622                 info = s3c2410_uart_inf_at;
1623         } else if (strcmp(dev->name, "s3c2440-uart") == 0) {
1624                 info = s3c2440_uart_inf_at;
1625         } else {
1626                 printk(KERN_ERR "s3c24xx: no driver for %s\n", dev->name);
1627                 return 0;
1628         }
1629 
1630         if (info == NULL) {
1631                 printk(KERN_ERR "s3c24xx: no driver for console\n");
1632                 return 0;
1633         }
1634 
1635         s3c24xx_serial_console.data = &s3c24xx_uart_drv;
1636         s3c24xx_serial_init_ports(info);
1637 
1638         register_console(&s3c24xx_serial_console);
1639         return 0;
1640 }
1641 
1642 console_initcall(s3c24xx_serial_initconsole);
1643 
1644 #endif /* CONFIG_SERIAL_S3C2410_CONSOLE */
1645 
1646 MODULE_LICENSE("GPL");
1647 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
1648 MODULE_DESCRIPTION("Samsung S3C2410/S3C2440 Serial port driver");
1649 
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