1 /* linux/drivers/serial/samsuing.c
3 * Driver core for Samsung SoC onboard UARTs.
5 * Ben Dooks, Copyright (c) 2003-2005,2008 Simtec Electronics
6 * http://armlinux.simtec.co.uk/
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 /* Hote on 2410 error handling
15 * The s3c2410 manual has a love/hate affair with the contents of the
16 * UERSTAT register in the UART blocks, and keeps marking some of the
17 * error bits as reserved. Having checked with the s3c2410x01,
18 * it copes with BREAKs properly, so I am happy to ignore the RESERVED
19 * feature from the latter versions of the manual.
21 * If it becomes aparrent that latter versions of the 2410 remove these
22 * bits, then action will have to be taken to differentiate the versions
23 * and change the policy on BREAK
28 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
32 #include <linux/module.h>
33 #include <linux/ioport.h>
35 #include <linux/platform_device.h>
36 #include <linux/init.h>
37 #include <linux/sysrq.h>
38 #include <linux/console.h>
39 #include <linux/tty.h>
40 #include <linux/tty_flip.h>
41 #include <linux/serial_core.h>
42 #include <linux/serial.h>
43 #include <linux/delay.h>
44 #include <linux/clk.h>
45 #include <linux/cpufreq.h>
49 #include <mach/hardware.h>
52 #include <plat/regs-serial.h>
56 /* UART name and device definitions */
58 #define S3C24XX_SERIAL_NAME "ttySAC"
59 #define S3C24XX_SERIAL_MAJOR 204
60 #define S3C24XX_SERIAL_MINOR 64
62 /* macros to change one thing to another */
64 #define tx_enabled(port) ((port)->unused[0])
65 #define rx_enabled(port) ((port)->unused[1])
67 /* flag to ignore all characters comming in */
68 #define RXSTAT_DUMMY_READ (0x10000000)
70 static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
72 return container_of(port, struct s3c24xx_uart_port, port);
75 /* translate a port to the device name */
77 static inline const char *s3c24xx_serial_portname(struct uart_port *port)
79 return to_platform_device(port->dev)->name;
82 static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
84 return (rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE);
87 static void s3c24xx_serial_rx_enable(struct uart_port *port)
90 unsigned int ucon, ufcon;
93 spin_lock_irqsave(&port->lock, flags);
95 while (--count && !s3c24xx_serial_txempty_nofifo(port))
98 ufcon = rd_regl(port, S3C2410_UFCON);
99 ufcon |= S3C2410_UFCON_RESETRX;
100 wr_regl(port, S3C2410_UFCON, ufcon);
102 ucon = rd_regl(port, S3C2410_UCON);
103 ucon |= S3C2410_UCON_RXIRQMODE;
104 wr_regl(port, S3C2410_UCON, ucon);
106 rx_enabled(port) = 1;
107 spin_unlock_irqrestore(&port->lock, flags);
110 static void s3c24xx_serial_rx_disable(struct uart_port *port)
115 spin_lock_irqsave(&port->lock, flags);
117 ucon = rd_regl(port, S3C2410_UCON);
118 ucon &= ~S3C2410_UCON_RXIRQMODE;
119 wr_regl(port, S3C2410_UCON, ucon);
121 rx_enabled(port) = 0;
122 spin_unlock_irqrestore(&port->lock, flags);
125 static void s3c24xx_serial_stop_tx(struct uart_port *port)
127 struct s3c24xx_uart_port *ourport = to_ourport(port);
129 if (tx_enabled(port)) {
130 disable_irq(ourport->tx_irq);
131 tx_enabled(port) = 0;
132 if (port->flags & UPF_CONS_FLOW)
133 s3c24xx_serial_rx_enable(port);
137 static void s3c24xx_serial_start_tx(struct uart_port *port)
139 struct s3c24xx_uart_port *ourport = to_ourport(port);
141 if (!tx_enabled(port)) {
142 if (port->flags & UPF_CONS_FLOW)
143 s3c24xx_serial_rx_disable(port);
145 enable_irq(ourport->tx_irq);
146 tx_enabled(port) = 1;
151 static void s3c24xx_serial_stop_rx(struct uart_port *port)
153 struct s3c24xx_uart_port *ourport = to_ourport(port);
155 if (rx_enabled(port)) {
156 dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
157 disable_irq(ourport->rx_irq);
158 rx_enabled(port) = 0;
162 static void s3c24xx_serial_enable_ms(struct uart_port *port)
166 static inline struct s3c24xx_uart_info *s3c24xx_port_to_info(struct uart_port *port)
168 return to_ourport(port)->info;
171 static inline struct s3c2410_uartcfg *s3c24xx_port_to_cfg(struct uart_port *port)
173 if (port->dev == NULL)
176 return (struct s3c2410_uartcfg *)port->dev->platform_data;
179 static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
180 unsigned long ufstat)
182 struct s3c24xx_uart_info *info = ourport->info;
184 if (ufstat & info->rx_fifofull)
185 return info->fifosize;
187 return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
191 /* ? - where has parity gone?? */
192 #define S3C2410_UERSTAT_PARITY (0x1000)
195 s3c24xx_serial_rx_chars(int irq, void *dev_id)
197 struct s3c24xx_uart_port *ourport = dev_id;
198 struct uart_port *port = &ourport->port;
199 struct tty_struct *tty = port->info->port.tty;
200 unsigned int ufcon, ch, flag, ufstat, uerstat;
203 while (max_count-- > 0) {
204 ufcon = rd_regl(port, S3C2410_UFCON);
205 ufstat = rd_regl(port, S3C2410_UFSTAT);
207 if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
210 uerstat = rd_regl(port, S3C2410_UERSTAT);
211 ch = rd_regb(port, S3C2410_URXH);
213 if (port->flags & UPF_CONS_FLOW) {
214 int txe = s3c24xx_serial_txempty_nofifo(port);
216 if (rx_enabled(port)) {
218 rx_enabled(port) = 0;
223 ufcon |= S3C2410_UFCON_RESETRX;
224 wr_regl(port, S3C2410_UFCON, ufcon);
225 rx_enabled(port) = 1;
232 /* insert the character into the buffer */
237 if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
238 dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
241 /* check for break */
242 if (uerstat & S3C2410_UERSTAT_BREAK) {
245 if (uart_handle_break(port))
249 if (uerstat & S3C2410_UERSTAT_FRAME)
250 port->icount.frame++;
251 if (uerstat & S3C2410_UERSTAT_OVERRUN)
252 port->icount.overrun++;
254 uerstat &= port->read_status_mask;
256 if (uerstat & S3C2410_UERSTAT_BREAK)
258 else if (uerstat & S3C2410_UERSTAT_PARITY)
260 else if (uerstat & (S3C2410_UERSTAT_FRAME |
261 S3C2410_UERSTAT_OVERRUN))
265 if (uart_handle_sysrq_char(port, ch))
268 uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
274 tty_flip_buffer_push(tty);
280 static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
282 struct s3c24xx_uart_port *ourport = id;
283 struct uart_port *port = &ourport->port;
284 struct circ_buf *xmit = &port->info->xmit;
288 wr_regb(port, S3C2410_UTXH, port->x_char);
294 /* if there isnt anything more to transmit, or the uart is now
295 * stopped, disable the uart and exit
298 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
299 s3c24xx_serial_stop_tx(port);
303 /* try and drain the buffer... */
305 while (!uart_circ_empty(xmit) && count-- > 0) {
306 if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
309 wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
310 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
314 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
315 uart_write_wakeup(port);
317 if (uart_circ_empty(xmit))
318 s3c24xx_serial_stop_tx(port);
324 static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
326 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
327 unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
328 unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
330 if (ufcon & S3C2410_UFCON_FIFOMODE) {
331 if ((ufstat & info->tx_fifomask) != 0 ||
332 (ufstat & info->tx_fifofull))
338 return s3c24xx_serial_txempty_nofifo(port);
341 /* no modem control lines */
342 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
344 unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
346 if (umstat & S3C2410_UMSTAT_CTS)
347 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
349 return TIOCM_CAR | TIOCM_DSR;
352 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
354 /* todo - possibly remove AFC and do manual CTS */
357 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
362 spin_lock_irqsave(&port->lock, flags);
364 ucon = rd_regl(port, S3C2410_UCON);
367 ucon |= S3C2410_UCON_SBREAK;
369 ucon &= ~S3C2410_UCON_SBREAK;
371 wr_regl(port, S3C2410_UCON, ucon);
373 spin_unlock_irqrestore(&port->lock, flags);
376 static void s3c24xx_serial_shutdown(struct uart_port *port)
378 struct s3c24xx_uart_port *ourport = to_ourport(port);
380 if (ourport->tx_claimed) {
381 free_irq(ourport->tx_irq, ourport);
382 tx_enabled(port) = 0;
383 ourport->tx_claimed = 0;
386 if (ourport->rx_claimed) {
387 free_irq(ourport->rx_irq, ourport);
388 ourport->rx_claimed = 0;
389 rx_enabled(port) = 0;
394 static int s3c24xx_serial_startup(struct uart_port *port)
396 struct s3c24xx_uart_port *ourport = to_ourport(port);
399 dbg("s3c24xx_serial_startup: port=%p (%08lx,%p)\n",
400 port->mapbase, port->membase);
402 rx_enabled(port) = 1;
404 ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_chars, 0,
405 s3c24xx_serial_portname(port), ourport);
408 printk(KERN_ERR "cannot get irq %d\n", ourport->rx_irq);
412 ourport->rx_claimed = 1;
414 dbg("requesting tx irq...\n");
416 tx_enabled(port) = 1;
418 ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_chars, 0,
419 s3c24xx_serial_portname(port), ourport);
422 printk(KERN_ERR "cannot get irq %d\n", ourport->tx_irq);
426 ourport->tx_claimed = 1;
428 dbg("s3c24xx_serial_startup ok\n");
430 /* the port reset code should have done the correct
431 * register setup for the port controls */
436 s3c24xx_serial_shutdown(port);
440 /* power power management control */
442 static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
445 struct s3c24xx_uart_port *ourport = to_ourport(port);
447 ourport->pm_level = level;
451 if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL)
452 clk_disable(ourport->baudclk);
454 clk_disable(ourport->clk);
458 clk_enable(ourport->clk);
460 if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL)
461 clk_enable(ourport->baudclk);
465 printk(KERN_ERR "s3c24xx_serial: unknown pm %d\n", level);
469 /* baud rate calculation
471 * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
472 * of different sources, including the peripheral clock ("pclk") and an
473 * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
474 * with a programmable extra divisor.
476 * The following code goes through the clock sources, and calculates the
477 * baud clocks (and the resultant actual baud rates) and then tries to
478 * pick the closest one and select that.
485 static struct s3c24xx_uart_clksrc tmp_clksrc = {
493 s3c24xx_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c)
495 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
497 return (info->get_clksrc)(port, c);
501 s3c24xx_serial_setsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c)
503 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
505 return (info->set_clksrc)(port, c);
509 struct s3c24xx_uart_clksrc *clksrc;
515 static int s3c24xx_serial_calcbaud(struct baud_calc *calc,
516 struct uart_port *port,
517 struct s3c24xx_uart_clksrc *clksrc,
522 calc->src = clk_get(port->dev, clksrc->name);
523 if (calc->src == NULL || IS_ERR(calc->src))
526 rate = clk_get_rate(calc->src);
527 rate /= clksrc->divisor;
529 calc->clksrc = clksrc;
530 calc->quot = (rate + (8 * baud)) / (16 * baud);
531 calc->calc = (rate / (calc->quot * 16));
537 static unsigned int s3c24xx_serial_getclk(struct uart_port *port,
538 struct s3c24xx_uart_clksrc **clksrc,
542 struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
543 struct s3c24xx_uart_clksrc *clkp;
544 struct baud_calc res[MAX_CLKS];
545 struct baud_calc *resptr, *best, *sptr;
551 if (cfg->clocks_size < 2) {
552 if (cfg->clocks_size == 0)
555 /* check to see if we're sourcing fclk, and if so we're
556 * going to have to update the clock source
559 if (strcmp(clkp->name, "fclk") == 0) {
560 struct s3c24xx_uart_clksrc src;
562 s3c24xx_serial_getsource(port, &src);
564 /* check that the port already using fclk, and if
565 * not, then re-select fclk
568 if (strcmp(src.name, clkp->name) == 0) {
569 s3c24xx_serial_setsource(port, clkp);
570 s3c24xx_serial_getsource(port, &src);
573 clkp->divisor = src.divisor;
576 s3c24xx_serial_calcbaud(res, port, clkp, baud);
582 for (i = 0; i < cfg->clocks_size; i++, clkp++) {
583 if (s3c24xx_serial_calcbaud(resptr, port, clkp, baud))
588 /* ok, we now need to select the best clock we found */
591 unsigned int deviation = (1<<30)|((1<<30)-1);
594 for (sptr = res; sptr < resptr; sptr++) {
595 calc_deviation = baud - sptr->calc;
596 if (calc_deviation < 0)
597 calc_deviation = -calc_deviation;
599 if (calc_deviation < deviation) {
601 deviation = calc_deviation;
606 /* store results to pass back */
608 *clksrc = best->clksrc;
614 static void s3c24xx_serial_set_termios(struct uart_port *port,
615 struct ktermios *termios,
616 struct ktermios *old)
618 struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
619 struct s3c24xx_uart_port *ourport = to_ourport(port);
620 struct s3c24xx_uart_clksrc *clksrc = NULL;
621 struct clk *clk = NULL;
623 unsigned int baud, quot;
628 * We don't support modem control lines.
630 termios->c_cflag &= ~(HUPCL | CMSPAR);
631 termios->c_cflag |= CLOCAL;
634 * Ask the core to calculate the divisor for us.
637 baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
639 if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
640 quot = port->custom_divisor;
642 quot = s3c24xx_serial_getclk(port, &clksrc, &clk, baud);
644 /* check to see if we need to change clock source */
646 if (ourport->clksrc != clksrc || ourport->baudclk != clk) {
647 s3c24xx_serial_setsource(port, clksrc);
649 if (ourport->baudclk != NULL && !IS_ERR(ourport->baudclk)) {
650 clk_disable(ourport->baudclk);
651 ourport->baudclk = NULL;
656 ourport->clksrc = clksrc;
657 ourport->baudclk = clk;
658 ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
661 switch (termios->c_cflag & CSIZE) {
663 dbg("config: 5bits/char\n");
664 ulcon = S3C2410_LCON_CS5;
667 dbg("config: 6bits/char\n");
668 ulcon = S3C2410_LCON_CS6;
671 dbg("config: 7bits/char\n");
672 ulcon = S3C2410_LCON_CS7;
676 dbg("config: 8bits/char\n");
677 ulcon = S3C2410_LCON_CS8;
681 /* preserve original lcon IR settings */
682 ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
684 if (termios->c_cflag & CSTOPB)
685 ulcon |= S3C2410_LCON_STOPB;
687 umcon = (termios->c_cflag & CRTSCTS) ? S3C2410_UMCOM_AFC : 0;
689 if (termios->c_cflag & PARENB) {
690 if (termios->c_cflag & PARODD)
691 ulcon |= S3C2410_LCON_PODD;
693 ulcon |= S3C2410_LCON_PEVEN;
695 ulcon |= S3C2410_LCON_PNONE;
698 spin_lock_irqsave(&port->lock, flags);
700 dbg("setting ulcon to %08x, brddiv to %d\n", ulcon, quot);
702 wr_regl(port, S3C2410_ULCON, ulcon);
703 wr_regl(port, S3C2410_UBRDIV, quot);
704 wr_regl(port, S3C2410_UMCON, umcon);
706 dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
707 rd_regl(port, S3C2410_ULCON),
708 rd_regl(port, S3C2410_UCON),
709 rd_regl(port, S3C2410_UFCON));
712 * Update the per-port timeout.
714 uart_update_timeout(port, termios->c_cflag, baud);
717 * Which character status flags are we interested in?
719 port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
720 if (termios->c_iflag & INPCK)
721 port->read_status_mask |= S3C2410_UERSTAT_FRAME | S3C2410_UERSTAT_PARITY;
724 * Which character status flags should we ignore?
726 port->ignore_status_mask = 0;
727 if (termios->c_iflag & IGNPAR)
728 port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
729 if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
730 port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
733 * Ignore all characters if CREAD is not set.
735 if ((termios->c_cflag & CREAD) == 0)
736 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
738 spin_unlock_irqrestore(&port->lock, flags);
741 static const char *s3c24xx_serial_type(struct uart_port *port)
743 switch (port->type) {
757 #define MAP_SIZE (0x100)
759 static void s3c24xx_serial_release_port(struct uart_port *port)
761 release_mem_region(port->mapbase, MAP_SIZE);
764 static int s3c24xx_serial_request_port(struct uart_port *port)
766 const char *name = s3c24xx_serial_portname(port);
767 return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY;
770 static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
772 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
774 if (flags & UART_CONFIG_TYPE &&
775 s3c24xx_serial_request_port(port) == 0)
776 port->type = info->type;
780 * verify the new serial_struct (for TIOCSSERIAL).
783 s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
785 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
787 if (ser->type != PORT_UNKNOWN && ser->type != info->type)
794 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
796 static struct console s3c24xx_serial_console;
798 #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
800 #define S3C24XX_SERIAL_CONSOLE NULL
803 static struct uart_ops s3c24xx_serial_ops = {
804 .pm = s3c24xx_serial_pm,
805 .tx_empty = s3c24xx_serial_tx_empty,
806 .get_mctrl = s3c24xx_serial_get_mctrl,
807 .set_mctrl = s3c24xx_serial_set_mctrl,
808 .stop_tx = s3c24xx_serial_stop_tx,
809 .start_tx = s3c24xx_serial_start_tx,
810 .stop_rx = s3c24xx_serial_stop_rx,
811 .enable_ms = s3c24xx_serial_enable_ms,
812 .break_ctl = s3c24xx_serial_break_ctl,
813 .startup = s3c24xx_serial_startup,
814 .shutdown = s3c24xx_serial_shutdown,
815 .set_termios = s3c24xx_serial_set_termios,
816 .type = s3c24xx_serial_type,
817 .release_port = s3c24xx_serial_release_port,
818 .request_port = s3c24xx_serial_request_port,
819 .config_port = s3c24xx_serial_config_port,
820 .verify_port = s3c24xx_serial_verify_port,
824 static struct uart_driver s3c24xx_uart_drv = {
825 .owner = THIS_MODULE,
826 .dev_name = "s3c2410_serial",
827 .nr = CONFIG_SERIAL_SAMSUNG_UARTS,
828 .cons = S3C24XX_SERIAL_CONSOLE,
829 .driver_name = S3C24XX_SERIAL_NAME,
830 .major = S3C24XX_SERIAL_MAJOR,
831 .minor = S3C24XX_SERIAL_MINOR,
834 static struct s3c24xx_uart_port s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS] = {
837 .lock = __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[0].port.lock),
839 .irq = IRQ_S3CUART_RX0,
842 .ops = &s3c24xx_serial_ops,
843 .flags = UPF_BOOT_AUTOCONF,
849 .lock = __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[1].port.lock),
851 .irq = IRQ_S3CUART_RX1,
854 .ops = &s3c24xx_serial_ops,
855 .flags = UPF_BOOT_AUTOCONF,
859 #if CONFIG_SERIAL_SAMSUNG_UARTS > 2
863 .lock = __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[2].port.lock),
865 .irq = IRQ_S3CUART_RX2,
868 .ops = &s3c24xx_serial_ops,
869 .flags = UPF_BOOT_AUTOCONF,
874 #if CONFIG_SERIAL_SAMSUNG_UARTS > 3
877 .lock = __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[3].port.lock),
879 .irq = IRQ_S3CUART_RX3,
882 .ops = &s3c24xx_serial_ops,
883 .flags = UPF_BOOT_AUTOCONF,
890 /* s3c24xx_serial_resetport
892 * wrapper to call the specific reset for this port (reset the fifos
896 static inline int s3c24xx_serial_resetport(struct uart_port *port,
897 struct s3c2410_uartcfg *cfg)
899 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
901 return (info->reset_port)(port, cfg);
905 #ifdef CONFIG_CPU_FREQ
907 static int s3c24xx_serial_cpufreq_transition(struct notifier_block *nb,
908 unsigned long val, void *data)
910 struct s3c24xx_uart_port *port;
911 struct uart_port *uport;
913 port = container_of(nb, struct s3c24xx_uart_port, freq_transition);
916 /* check to see if port is enabled */
918 if (port->pm_level != 0)
921 /* try and work out if the baudrate is changing, we can detect
922 * a change in rate, but we do not have support for detecting
923 * a disturbance in the clock-rate over the change.
926 if (IS_ERR(port->clk))
929 if (port->baudclk_rate == clk_get_rate(port->clk))
932 if (val == CPUFREQ_PRECHANGE) {
933 /* we should really shut the port down whilst the
934 * frequency change is in progress. */
936 } else if (val == CPUFREQ_POSTCHANGE) {
937 struct ktermios *termios;
938 struct tty_struct *tty;
940 if (uport->info == NULL)
943 tty = uport->info->port.tty;
948 termios = tty->termios;
950 if (termios == NULL) {
951 printk(KERN_WARNING "%s: no termios?\n", __func__);
955 s3c24xx_serial_set_termios(uport, termios, NULL);
962 static inline int s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
964 port->freq_transition.notifier_call = s3c24xx_serial_cpufreq_transition;
966 return cpufreq_register_notifier(&port->freq_transition,
967 CPUFREQ_TRANSITION_NOTIFIER);
970 static inline void s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
972 cpufreq_unregister_notifier(&port->freq_transition,
973 CPUFREQ_TRANSITION_NOTIFIER);
977 static inline int s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
982 static inline void s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
987 /* s3c24xx_serial_init_port
989 * initialise a single serial port from the platform device given
992 static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
993 struct s3c24xx_uart_info *info,
994 struct platform_device *platdev)
996 struct uart_port *port = &ourport->port;
997 struct s3c2410_uartcfg *cfg;
998 struct resource *res;
1001 dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev);
1003 if (platdev == NULL)
1006 cfg = s3c24xx_dev_to_cfg(&platdev->dev);
1008 if (port->mapbase != 0)
1011 if (cfg->hwport > CONFIG_SERIAL_SAMSUNG_UARTS) {
1012 printk(KERN_ERR "%s: port %d bigger than %d\n", __func__,
1013 cfg->hwport, CONFIG_SERIAL_SAMSUNG_UARTS);
1017 /* setup info for port */
1018 port->dev = &platdev->dev;
1019 ourport->info = info;
1021 /* copy the info in from provided structure */
1022 ourport->port.fifosize = info->fifosize;
1024 dbg("s3c24xx_serial_init_port: %p (hw %d)...\n", port, cfg->hwport);
1028 if (cfg->uart_flags & UPF_CONS_FLOW) {
1029 dbg("s3c24xx_serial_init_port: enabling flow control\n");
1030 port->flags |= UPF_CONS_FLOW;
1033 /* sort our the physical and virtual addresses for each UART */
1035 res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
1037 printk(KERN_ERR "failed to find memory resource for uart\n");
1041 dbg("resource %p (%lx..%lx)\n", res, res->start, res->end);
1043 port->mapbase = res->start;
1044 port->membase = S3C_VA_UART + res->start - (S3C_PA_UART & 0xfff00000);
1045 ret = platform_get_irq(platdev, 0);
1050 ourport->rx_irq = ret;
1051 ourport->tx_irq = ret + 1;
1054 ret = platform_get_irq(platdev, 1);
1056 ourport->tx_irq = ret;
1058 ourport->clk = clk_get(&platdev->dev, "uart");
1060 dbg("port: map=%08x, mem=%08x, irq=%d (%d,%d), clock=%ld\n",
1061 port->mapbase, port->membase, port->irq,
1062 ourport->rx_irq, ourport->tx_irq, port->uartclk);
1064 /* reset the fifos (and setup the uart) */
1065 s3c24xx_serial_resetport(port, cfg);
1069 static ssize_t s3c24xx_serial_show_clksrc(struct device *dev,
1070 struct device_attribute *attr,
1073 struct uart_port *port = s3c24xx_dev_to_port(dev);
1074 struct s3c24xx_uart_port *ourport = to_ourport(port);
1076 return snprintf(buf, PAGE_SIZE, "* %s\n", ourport->clksrc->name);
1079 static DEVICE_ATTR(clock_source, S_IRUGO, s3c24xx_serial_show_clksrc, NULL);
1081 /* Device driver serial port probe */
1083 static int probe_index;
1085 int s3c24xx_serial_probe(struct platform_device *dev,
1086 struct s3c24xx_uart_info *info)
1088 struct s3c24xx_uart_port *ourport;
1091 dbg("s3c24xx_serial_probe(%p, %p) %d\n", dev, info, probe_index);
1093 ourport = &s3c24xx_serial_ports[probe_index];
1096 dbg("%s: initialising port %p...\n", __func__, ourport);
1098 ret = s3c24xx_serial_init_port(ourport, info, dev);
1102 dbg("%s: adding port\n", __func__);
1103 uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
1104 platform_set_drvdata(dev, &ourport->port);
1106 ret = device_create_file(&dev->dev, &dev_attr_clock_source);
1108 printk(KERN_ERR "%s: failed to add clksrc attr.\n", __func__);
1110 ret = s3c24xx_serial_cpufreq_register(ourport);
1112 dev_err(&dev->dev, "failed to add cpufreq notifier\n");
1120 EXPORT_SYMBOL_GPL(s3c24xx_serial_probe);
1122 int s3c24xx_serial_remove(struct platform_device *dev)
1124 struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
1127 s3c24xx_serial_cpufreq_deregister(to_ourport(port));
1128 device_remove_file(&dev->dev, &dev_attr_clock_source);
1129 uart_remove_one_port(&s3c24xx_uart_drv, port);
1135 EXPORT_SYMBOL_GPL(s3c24xx_serial_remove);
1137 /* UART power management code */
1141 static int s3c24xx_serial_suspend(struct platform_device *dev, pm_message_t state)
1143 struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
1146 uart_suspend_port(&s3c24xx_uart_drv, port);
1151 static int s3c24xx_serial_resume(struct platform_device *dev)
1153 struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
1154 struct s3c24xx_uart_port *ourport = to_ourport(port);
1157 clk_enable(ourport->clk);
1158 s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
1159 clk_disable(ourport->clk);
1161 uart_resume_port(&s3c24xx_uart_drv, port);
1168 int s3c24xx_serial_init(struct platform_driver *drv,
1169 struct s3c24xx_uart_info *info)
1171 dbg("s3c24xx_serial_init(%p,%p)\n", drv, info);
1174 drv->suspend = s3c24xx_serial_suspend;
1175 drv->resume = s3c24xx_serial_resume;
1178 return platform_driver_register(drv);
1181 EXPORT_SYMBOL_GPL(s3c24xx_serial_init);
1183 /* module initialisation code */
1185 static int __init s3c24xx_serial_modinit(void)
1189 ret = uart_register_driver(&s3c24xx_uart_drv);
1191 printk(KERN_ERR "failed to register UART driver\n");
1198 static void __exit s3c24xx_serial_modexit(void)
1200 uart_unregister_driver(&s3c24xx_uart_drv);
1203 module_init(s3c24xx_serial_modinit);
1204 module_exit(s3c24xx_serial_modexit);
1208 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1210 static struct uart_port *cons_uart;
1213 s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
1215 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1216 unsigned long ufstat, utrstat;
1218 if (ufcon & S3C2410_UFCON_FIFOMODE) {
1219 /* fifo mode - check ammount of data in fifo registers... */
1221 ufstat = rd_regl(port, S3C2410_UFSTAT);
1222 return (ufstat & info->tx_fifofull) ? 0 : 1;
1225 /* in non-fifo mode, we go and use the tx buffer empty */
1227 utrstat = rd_regl(port, S3C2410_UTRSTAT);
1228 return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
1232 s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
1234 unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
1235 while (!s3c24xx_serial_console_txrdy(port, ufcon))
1237 wr_regb(cons_uart, S3C2410_UTXH, ch);
1241 s3c24xx_serial_console_write(struct console *co, const char *s,
1244 uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
1248 s3c24xx_serial_get_options(struct uart_port *port, int *baud,
1249 int *parity, int *bits)
1251 struct s3c24xx_uart_clksrc clksrc;
1255 unsigned int ubrdiv;
1258 ulcon = rd_regl(port, S3C2410_ULCON);
1259 ucon = rd_regl(port, S3C2410_UCON);
1260 ubrdiv = rd_regl(port, S3C2410_UBRDIV);
1262 dbg("s3c24xx_serial_get_options: port=%p\n"
1263 "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
1264 port, ulcon, ucon, ubrdiv);
1266 if ((ucon & 0xf) != 0) {
1267 /* consider the serial port configured if the tx/rx mode set */
1269 switch (ulcon & S3C2410_LCON_CSMASK) {
1270 case S3C2410_LCON_CS5:
1273 case S3C2410_LCON_CS6:
1276 case S3C2410_LCON_CS7:
1280 case S3C2410_LCON_CS8:
1285 switch (ulcon & S3C2410_LCON_PMASK) {
1286 case S3C2410_LCON_PEVEN:
1290 case S3C2410_LCON_PODD:
1294 case S3C2410_LCON_PNONE:
1299 /* now calculate the baud rate */
1301 s3c24xx_serial_getsource(port, &clksrc);
1303 clk = clk_get(port->dev, clksrc.name);
1304 if (!IS_ERR(clk) && clk != NULL)
1305 rate = clk_get_rate(clk) / clksrc.divisor;
1310 *baud = rate / (16 * (ubrdiv + 1));
1311 dbg("calculated baud %d\n", *baud);
1316 /* s3c24xx_serial_init_ports
1318 * initialise the serial ports from the machine provided initialisation
1322 static int s3c24xx_serial_init_ports(struct s3c24xx_uart_info *info)
1324 struct s3c24xx_uart_port *ptr = s3c24xx_serial_ports;
1325 struct platform_device **platdev_ptr;
1328 dbg("s3c24xx_serial_init_ports: initialising ports...\n");
1330 platdev_ptr = s3c24xx_uart_devs;
1332 for (i = 0; i < CONFIG_SERIAL_SAMSUNG_UARTS; i++, ptr++, platdev_ptr++) {
1333 s3c24xx_serial_init_port(ptr, info, *platdev_ptr);
1340 s3c24xx_serial_console_setup(struct console *co, char *options)
1342 struct uart_port *port;
1348 dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
1349 co, co->index, options);
1351 /* is this a valid port */
1353 if (co->index == -1 || co->index >= CONFIG_SERIAL_SAMSUNG_UARTS)
1356 port = &s3c24xx_serial_ports[co->index].port;
1358 /* is the port configured? */
1360 if (port->mapbase == 0x0) {
1362 port = &s3c24xx_serial_ports[co->index].port;
1367 dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
1370 * Check whether an invalid uart number has been specified, and
1371 * if so, search for the first available port that does have
1375 uart_parse_options(options, &baud, &parity, &bits, &flow);
1377 s3c24xx_serial_get_options(port, &baud, &parity, &bits);
1379 dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
1381 return uart_set_options(port, co, baud, parity, bits, flow);
1384 /* s3c24xx_serial_initconsole
1386 * initialise the console from one of the uart drivers
1389 static struct console s3c24xx_serial_console = {
1390 .name = S3C24XX_SERIAL_NAME,
1391 .device = uart_console_device,
1392 .flags = CON_PRINTBUFFER,
1394 .write = s3c24xx_serial_console_write,
1395 .setup = s3c24xx_serial_console_setup
1398 int s3c24xx_serial_initconsole(struct platform_driver *drv,
1399 struct s3c24xx_uart_info *info)
1402 struct platform_device *dev = s3c24xx_uart_devs[0];
1404 dbg("s3c24xx_serial_initconsole\n");
1406 /* select driver based on the cpu */
1409 printk(KERN_ERR "s3c24xx: no devices for console init\n");
1413 if (strcmp(dev->name, drv->driver.name) != 0)
1416 s3c24xx_serial_console.data = &s3c24xx_uart_drv;
1417 s3c24xx_serial_init_ports(info);
1419 register_console(&s3c24xx_serial_console);
1423 #endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
1425 MODULE_DESCRIPTION("Samsung SoC Serial port driver");
1426 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
1427 MODULE_LICENSE("GPL v2");