/* 68328serial.c: Serial port driver for 68328 microcontroller * * Copyright (C) 1995 David S. Miller <davem@caip.rutgers.edu> * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com> * Copyright (C) 1998, 1999 D. Jeff Dionne <jeff@uclinux.org> * Copyright (C) 1999 Vladimir Gurevich <vgurevic@cisco.com> * Copyright (C) 2002-2003 David McCullough <davidm@snapgear.com> * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com> * * VZ Support/Fixes Evan Stawnyczy <e@lineo.ca> * Multiple UART support Daniel Potts <danielp@cse.unsw.edu.au> * Power management support Daniel Potts <danielp@cse.unsw.edu.au> * VZ Second Serial Port enable Phil Wilshire * 2.4/2.5 port David McCullough */ #include <asm/dbg.h> #include <linux/module.h> #include <linux/errno.h> #include <linux/signal.h> #include <linux/sched.h> #include <linux/timer.h> #include <linux/interrupt.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/major.h> #include <linux/string.h> #include <linux/fcntl.h> #include <linux/mm.h> #include <linux/kernel.h> #include <linux/console.h> #include <linux/reboot.h> #include <linux/keyboard.h> #include <linux/init.h> #include <linux/pm.h> #include <linux/bitops.h> #include <linux/delay.h> #include <asm/io.h> #include <asm/irq.h> #include <asm/system.h> #include <asm/delay.h> #include <asm/uaccess.h> /* (es) */ /* note: perhaps we can murge these files, so that you can just * define 1 of them, and they can sort that out for themselves */ #if defined(CONFIG_M68EZ328) #include <asm/MC68EZ328.h> #else #if defined(CONFIG_M68VZ328) #include <asm/MC68VZ328.h> #else #include <asm/MC68328.h> #endif /* CONFIG_M68VZ328 */ #endif /* CONFIG_M68EZ328 */ #include "68328serial.h" /* Turn off usage of real serial interrupt code, to "support" Copilot */ #ifdef CONFIG_XCOPILOT_BUGS #undef USE_INTS #else #define USE_INTS #endif static struct m68k_serial m68k_soft[NR_PORTS]; static unsigned int uart_irqs[NR_PORTS] = UART_IRQ_DEFNS; /* multiple ports are contiguous in memory */ m68328_uart *uart_addr = (m68328_uart *)USTCNT_ADDR; struct tty_struct m68k_ttys; struct m68k_serial *m68k_consinfo = 0; #define M68K_CLOCK (16667000) /* FIXME: 16MHz is likely wrong */ #ifdef CONFIG_CONSOLE extern wait_queue_head_t keypress_wait; #endif struct tty_driver *serial_driver; /* number of characters left in xmit buffer before we ask for more */ #define WAKEUP_CHARS 256 /* Debugging... DEBUG_INTR is bad to use when one of the zs * lines is your console ;( */ #undef SERIAL_DEBUG_INTR #undef SERIAL_DEBUG_OPEN #undef SERIAL_DEBUG_FLOW #define RS_ISR_PASS_LIMIT 256 static void change_speed(struct m68k_serial *info); /* * Setup for console. Argument comes from the boot command line. */ #if defined(CONFIG_M68EZ328ADS) || defined(CONFIG_ALMA_ANS) || defined(CONFIG_DRAGONIXVZ) #define CONSOLE_BAUD_RATE 115200 #define DEFAULT_CBAUD B115200 #else /* (es) */ /* note: this is messy, but it works, again, perhaps defined somewhere else?*/ #ifdef CONFIG_M68VZ328 #define CONSOLE_BAUD_RATE 19200 #define DEFAULT_CBAUD B19200 #endif /* (/es) */ #endif #ifndef CONSOLE_BAUD_RATE #define CONSOLE_BAUD_RATE 9600 #define DEFAULT_CBAUD B9600 #endif static int m68328_console_initted = 0; static int m68328_console_baud = CONSOLE_BAUD_RATE; static int m68328_console_cbaud = DEFAULT_CBAUD; static inline int serial_paranoia_check(struct m68k_serial *info, char *name, const char *routine) { #ifdef SERIAL_PARANOIA_CHECK static const char *badmagic = "Warning: bad magic number for serial struct %s in %s\n"; static const char *badinfo = "Warning: null m68k_serial for %s in %s\n"; if (!info) { printk(badinfo, name, routine); return 1; } if (info->magic != SERIAL_MAGIC) { printk(badmagic, name, routine); return 1; } #endif return 0; } /* * This is used to figure out the divisor speeds and the timeouts */ static int baud_table[] = { 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 0 }; #define BAUD_TABLE_SIZE (sizeof(baud_table)/sizeof(baud_table[0])) /* Sets or clears DTR/RTS on the requested line */ static inline void m68k_rtsdtr(struct m68k_serial *ss, int set) { if (set) { /* set the RTS/CTS line */ } else { /* clear it */ } return; } /* Utility routines */ static inline int get_baud(struct m68k_serial *ss) { unsigned long result = 115200; unsigned short int baud = uart_addr[ss->line].ubaud; if (GET_FIELD(baud, UBAUD_PRESCALER) == 0x38) result = 38400; result >>= GET_FIELD(baud, UBAUD_DIVIDE); return result; } /* * ------------------------------------------------------------ * rs_stop() and rs_start() * * This routines are called before setting or resetting tty->stopped. * They enable or disable transmitter interrupts, as necessary. * ------------------------------------------------------------ */ static void rs_stop(struct tty_struct *tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; if (serial_paranoia_check(info, tty->name, "rs_stop")) return; local_irq_save(flags); uart->ustcnt &= ~USTCNT_TXEN; local_irq_restore(flags); } static int rs_put_char(char ch) { int flags, loops = 0; local_irq_save(flags); while (!(UTX & UTX_TX_AVAIL) && (loops < 1000)) { loops++; udelay(5); } UTX_TXDATA = ch; udelay(5); local_irq_restore(flags); return 1; } static void rs_start(struct tty_struct *tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; if (serial_paranoia_check(info, tty->name, "rs_start")) return; local_irq_save(flags); if (info->xmit_cnt && info->xmit_buf && !(uart->ustcnt & USTCNT_TXEN)) { #ifdef USE_INTS uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK; #else uart->ustcnt |= USTCNT_TXEN; #endif } local_irq_restore(flags); } /* Drop into either the boot monitor or kadb upon receiving a break * from keyboard/console input. */ static void batten_down_hatches(void) { /* Drop into the debugger */ } static void status_handle(struct m68k_serial *info, unsigned short status) { #if 0 if(status & DCD) { if((info->port.tty->termios->c_cflag & CRTSCTS) && ((info->curregs[3] & AUTO_ENAB)==0)) { info->curregs[3] |= AUTO_ENAB; info->pendregs[3] |= AUTO_ENAB; write_zsreg(info->m68k_channel, 3, info->curregs[3]); } } else { if((info->curregs[3] & AUTO_ENAB)) { info->curregs[3] &= ~AUTO_ENAB; info->pendregs[3] &= ~AUTO_ENAB; write_zsreg(info->m68k_channel, 3, info->curregs[3]); } } #endif /* If this is console input and this is a * 'break asserted' status change interrupt * see if we can drop into the debugger */ if((status & URX_BREAK) && info->break_abort) batten_down_hatches(); return; } static void receive_chars(struct m68k_serial *info, unsigned short rx) { struct tty_struct *tty = info->port.tty; m68328_uart *uart = &uart_addr[info->line]; unsigned char ch, flag; /* * This do { } while() loop will get ALL chars out of Rx FIFO */ #ifndef CONFIG_XCOPILOT_BUGS do { #endif ch = GET_FIELD(rx, URX_RXDATA); if(info->is_cons) { if(URX_BREAK & rx) { /* whee, break received */ status_handle(info, rx); return; #ifdef CONFIG_MAGIC_SYSRQ } else if (ch == 0x10) { /* ^P */ show_state(); show_free_areas(); show_buffers(); /* show_net_buffers(); */ return; } else if (ch == 0x12) { /* ^R */ emergency_restart(); return; #endif /* CONFIG_MAGIC_SYSRQ */ } /* It is a 'keyboard interrupt' ;-) */ #ifdef CONFIG_CONSOLE wake_up(&keypress_wait); #endif } if(!tty) goto clear_and_exit; flag = TTY_NORMAL; if(rx & URX_PARITY_ERROR) { flag = TTY_PARITY; status_handle(info, rx); } else if(rx & URX_OVRUN) { flag = TTY_OVERRUN; status_handle(info, rx); } else if(rx & URX_FRAME_ERROR) { flag = TTY_FRAME; status_handle(info, rx); } tty_insert_flip_char(tty, ch, flag); #ifndef CONFIG_XCOPILOT_BUGS } while((rx = uart->urx.w) & URX_DATA_READY); #endif tty_schedule_flip(tty); clear_and_exit: return; } static void transmit_chars(struct m68k_serial *info) { m68328_uart *uart = &uart_addr[info->line]; if (info->x_char) { /* Send next char */ uart->utx.b.txdata = info->x_char; info->x_char = 0; goto clear_and_return; } if((info->xmit_cnt <= 0) || info->port.tty->stopped) { /* That's peculiar... TX ints off */ uart->ustcnt &= ~USTCNT_TX_INTR_MASK; goto clear_and_return; } /* Send char */ uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++]; info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1); info->xmit_cnt--; if (info->xmit_cnt < WAKEUP_CHARS) schedule_work(&info->tqueue); if(info->xmit_cnt <= 0) { /* All done for now... TX ints off */ uart->ustcnt &= ~USTCNT_TX_INTR_MASK; goto clear_and_return; } clear_and_return: /* Clear interrupt (should be auto)*/ return; } /* * This is the serial driver's generic interrupt routine */ irqreturn_t rs_interrupt(int irq, void *dev_id) { struct m68k_serial *info = dev_id; m68328_uart *uart; unsigned short rx; unsigned short tx; uart = &uart_addr[info->line]; rx = uart->urx.w; #ifdef USE_INTS tx = uart->utx.w; if (rx & URX_DATA_READY) receive_chars(info, rx); if (tx & UTX_TX_AVAIL) transmit_chars(info); #else receive_chars(info, rx); #endif return IRQ_HANDLED; } static void do_softint(struct work_struct *work) { struct m68k_serial *info = container_of(work, struct m68k_serial, tqueue); struct tty_struct *tty; tty = info->port.tty; if (!tty) return; #if 0 if (clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) { tty_wakeup(tty); } #endif } /* * This routine is called from the scheduler tqueue when the interrupt * routine has signalled that a hangup has occurred. The path of * hangup processing is: * * serial interrupt routine -> (scheduler tqueue) -> * do_serial_hangup() -> tty->hangup() -> rs_hangup() * */ static void do_serial_hangup(struct work_struct *work) { struct m68k_serial *info = container_of(work, struct m68k_serial, tqueue_hangup); struct tty_struct *tty; tty = info->port.tty; if (!tty) return; tty_hangup(tty); } static int startup(struct m68k_serial * info) { m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; if (info->flags & S_INITIALIZED) return 0; if (!info->xmit_buf) { info->xmit_buf = (unsigned char *) __get_free_page(GFP_KERNEL); if (!info->xmit_buf) return -ENOMEM; } local_irq_save(flags); /* * Clear the FIFO buffers and disable them * (they will be reenabled in change_speed()) */ uart->ustcnt = USTCNT_UEN; info->xmit_fifo_size = 1; uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_TXEN; (void)uart->urx.w; /* * Finally, enable sequencing and interrupts */ #ifdef USE_INTS uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK | USTCNT_TX_INTR_MASK; #else uart->ustcnt = USTCNT_UEN | USTCNT_RXEN | USTCNT_RX_INTR_MASK; #endif if (info->port.tty) clear_bit(TTY_IO_ERROR, &info->port.tty->flags); info->xmit_cnt = info->xmit_head = info->xmit_tail = 0; /* * and set the speed of the serial port */ change_speed(info); info->flags |= S_INITIALIZED; local_irq_restore(flags); return 0; } /* * This routine will shutdown a serial port; interrupts are disabled, and * DTR is dropped if the hangup on close termio flag is on. */ static void shutdown(struct m68k_serial * info) { m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; uart->ustcnt = 0; /* All off! */ if (!(info->flags & S_INITIALIZED)) return; local_irq_save(flags); if (info->xmit_buf) { free_page((unsigned long) info->xmit_buf); info->xmit_buf = 0; } if (info->port.tty) set_bit(TTY_IO_ERROR, &info->port.tty->flags); info->flags &= ~S_INITIALIZED; local_irq_restore(flags); } struct { int divisor, prescale; } #ifndef CONFIG_M68VZ328 hw_baud_table[18] = { {0,0}, /* 0 */ {0,0}, /* 50 */ {0,0}, /* 75 */ {0,0}, /* 110 */ {0,0}, /* 134 */ {0,0}, /* 150 */ {0,0}, /* 200 */ {7,0x26}, /* 300 */ {6,0x26}, /* 600 */ {5,0x26}, /* 1200 */ {0,0}, /* 1800 */ {4,0x26}, /* 2400 */ {3,0x26}, /* 4800 */ {2,0x26}, /* 9600 */ {1,0x26}, /* 19200 */ {0,0x26}, /* 38400 */ {1,0x38}, /* 57600 */ {0,0x38}, /* 115200 */ }; #else hw_baud_table[18] = { {0,0}, /* 0 */ {0,0}, /* 50 */ {0,0}, /* 75 */ {0,0}, /* 110 */ {0,0}, /* 134 */ {0,0}, /* 150 */ {0,0}, /* 200 */ {0,0}, /* 300 */ {7,0x26}, /* 600 */ {6,0x26}, /* 1200 */ {0,0}, /* 1800 */ {5,0x26}, /* 2400 */ {4,0x26}, /* 4800 */ {3,0x26}, /* 9600 */ {2,0x26}, /* 19200 */ {1,0x26}, /* 38400 */ {0,0x26}, /* 57600 */ {1,0x38}, /* 115200 */ }; #endif /* rate = 1036800 / ((65 - prescale) * (1<<divider)) */ /* * This routine is called to set the UART divisor registers to match * the specified baud rate for a serial port. */ static void change_speed(struct m68k_serial *info) { m68328_uart *uart = &uart_addr[info->line]; unsigned short port; unsigned short ustcnt; unsigned cflag; int i; if (!info->port.tty || !info->port.tty->termios) return; cflag = info->port.tty->termios->c_cflag; if (!(port = info->port)) return; ustcnt = uart->ustcnt; uart->ustcnt = ustcnt & ~USTCNT_TXEN; i = cflag & CBAUD; if (i & CBAUDEX) { i = (i & ~CBAUDEX) + B38400; } info->baud = baud_table[i]; uart->ubaud = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) | PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale); ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7); if ((cflag & CSIZE) == CS8) ustcnt |= USTCNT_8_7; if (cflag & CSTOPB) ustcnt |= USTCNT_STOP; if (cflag & PARENB) ustcnt |= USTCNT_PARITYEN; if (cflag & PARODD) ustcnt |= USTCNT_ODD_EVEN; #ifdef CONFIG_SERIAL_68328_RTS_CTS if (cflag & CRTSCTS) { uart->utx.w &= ~ UTX_NOCTS; } else { uart->utx.w |= UTX_NOCTS; } #endif ustcnt |= USTCNT_TXEN; uart->ustcnt = ustcnt; return; } /* * Fair output driver allows a process to speak. */ static void rs_fair_output(void) { int left; /* Output no more than that */ unsigned long flags; struct m68k_serial *info = &m68k_soft[0]; char c; if (info == 0) return; if (info->xmit_buf == 0) return; local_irq_save(flags); left = info->xmit_cnt; while (left != 0) { c = info->xmit_buf[info->xmit_tail]; info->xmit_tail = (info->xmit_tail+1) & (SERIAL_XMIT_SIZE-1); info->xmit_cnt--; local_irq_restore(flags); rs_put_char(c); local_irq_save(flags); left = min(info->xmit_cnt, left-1); } /* Last character is being transmitted now (hopefully). */ udelay(5); local_irq_restore(flags); return; } /* * m68k_console_print is registered for printk. */ void console_print_68328(const char *p) { char c; while((c=*(p++)) != 0) { if(c == '\n') rs_put_char('\r'); rs_put_char(c); } /* Comment this if you want to have a strict interrupt-driven output */ rs_fair_output(); return; } static void rs_set_ldisc(struct tty_struct *tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; if (serial_paranoia_check(info, tty->name, "rs_set_ldisc")) return; info->is_cons = (tty->termios->c_line == N_TTY); printk("ttyS%d console mode %s\n", info->line, info->is_cons ? "on" : "off"); } static void rs_flush_chars(struct tty_struct *tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; if (serial_paranoia_check(info, tty->name, "rs_flush_chars")) return; #ifndef USE_INTS for(;;) { #endif /* Enable transmitter */ local_irq_save(flags); if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped || !info->xmit_buf) { local_irq_restore(flags); return; } #ifdef USE_INTS uart->ustcnt |= USTCNT_TXEN | USTCNT_TX_INTR_MASK; #else uart->ustcnt |= USTCNT_TXEN; #endif #ifdef USE_INTS if (uart->utx.w & UTX_TX_AVAIL) { #else if (1) { #endif /* Send char */ uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++]; info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1); info->xmit_cnt--; } #ifndef USE_INTS while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5); } #endif local_irq_restore(flags); } extern void console_printn(const char * b, int count); static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count) { int c, total = 0; struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; if (serial_paranoia_check(info, tty->name, "rs_write")) return 0; if (!tty || !info->xmit_buf) return 0; local_save_flags(flags); while (1) { local_irq_disable(); c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1, SERIAL_XMIT_SIZE - info->xmit_head)); local_irq_restore(flags); if (c <= 0) break; memcpy(info->xmit_buf + info->xmit_head, buf, c); local_irq_disable(); info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1); info->xmit_cnt += c; local_irq_restore(flags); buf += c; count -= c; total += c; } if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) { /* Enable transmitter */ local_irq_disable(); #ifndef USE_INTS while(info->xmit_cnt) { #endif uart->ustcnt |= USTCNT_TXEN; #ifdef USE_INTS uart->ustcnt |= USTCNT_TX_INTR_MASK; #else while (!(uart->utx.w & UTX_TX_AVAIL)) udelay(5); #endif if (uart->utx.w & UTX_TX_AVAIL) { uart->utx.b.txdata = info->xmit_buf[info->xmit_tail++]; info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1); info->xmit_cnt--; } #ifndef USE_INTS } #endif local_irq_restore(flags); } return total; } static int rs_write_room(struct tty_struct *tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; int ret; if (serial_paranoia_check(info, tty->name, "rs_write_room")) return 0; ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1; if (ret < 0) ret = 0; return ret; } static int rs_chars_in_buffer(struct tty_struct *tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer")) return 0; return info->xmit_cnt; } static void rs_flush_buffer(struct tty_struct *tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; unsigned long flags; if (serial_paranoia_check(info, tty->name, "rs_flush_buffer")) return; local_irq_save(flags); info->xmit_cnt = info->xmit_head = info->xmit_tail = 0; local_irq_restore(flags); tty_wakeup(tty); } /* * ------------------------------------------------------------ * rs_throttle() * * This routine is called by the upper-layer tty layer to signal that * incoming characters should be throttled. * ------------------------------------------------------------ */ static void rs_throttle(struct tty_struct * tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; if (serial_paranoia_check(info, tty->name, "rs_throttle")) return; if (I_IXOFF(tty)) info->x_char = STOP_CHAR(tty); /* Turn off RTS line (do this atomic) */ } static void rs_unthrottle(struct tty_struct * tty) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; if (serial_paranoia_check(info, tty->name, "rs_unthrottle")) return; if (I_IXOFF(tty)) { if (info->x_char) info->x_char = 0; else info->x_char = START_CHAR(tty); } /* Assert RTS line (do this atomic) */ } /* * ------------------------------------------------------------ * rs_ioctl() and friends * ------------------------------------------------------------ */ static int get_serial_info(struct m68k_serial * info, struct serial_struct * retinfo) { struct serial_struct tmp; if (!retinfo) return -EFAULT; memset(&tmp, 0, sizeof(tmp)); tmp.type = info->type; tmp.line = info->line; tmp.port = info->port; tmp.irq = info->irq; tmp.flags = info->flags; tmp.baud_base = info->baud_base; tmp.close_delay = info->close_delay; tmp.closing_wait = info->closing_wait; tmp.custom_divisor = info->custom_divisor; copy_to_user(retinfo,&tmp,sizeof(*retinfo)); return 0; } static int set_serial_info(struct m68k_serial * info, struct serial_struct * new_info) { struct serial_struct new_serial; struct m68k_serial old_info; int retval = 0; if (!new_info) return -EFAULT; copy_from_user(&new_serial,new_info,sizeof(new_serial)); old_info = *info; if (!capable(CAP_SYS_ADMIN)) { if ((new_serial.baud_base != info->baud_base) || (new_serial.type != info->type) || (new_serial.close_delay != info->close_delay) || ((new_serial.flags & ~S_USR_MASK) != (info->flags & ~S_USR_MASK))) return -EPERM; info->flags = ((info->flags & ~S_USR_MASK) | (new_serial.flags & S_USR_MASK)); info->custom_divisor = new_serial.custom_divisor; goto check_and_exit; } if (info->count > 1) return -EBUSY; /* * OK, past this point, all the error checking has been done. * At this point, we start making changes..... */ info->baud_base = new_serial.baud_base; info->flags = ((info->flags & ~S_FLAGS) | (new_serial.flags & S_FLAGS)); info->type = new_serial.type; info->close_delay = new_serial.close_delay; info->closing_wait = new_serial.closing_wait; check_and_exit: retval = startup(info); return retval; } /* * get_lsr_info - get line status register info * * Purpose: Let user call ioctl() to get info when the UART physically * is emptied. On bus types like RS485, the transmitter must * release the bus after transmitting. This must be done when * the transmit shift register is empty, not be done when the * transmit holding register is empty. This functionality * allows an RS485 driver to be written in user space. */ static int get_lsr_info(struct m68k_serial * info, unsigned int *value) { #ifdef CONFIG_SERIAL_68328_RTS_CTS m68328_uart *uart = &uart_addr[info->line]; #endif unsigned char status; unsigned long flags; local_irq_save(flags); #ifdef CONFIG_SERIAL_68328_RTS_CTS status = (uart->utx.w & UTX_CTS_STAT) ? 1 : 0; #else status = 0; #endif local_irq_restore(flags); put_user(status,value); return 0; } /* * This routine sends a break character out the serial port. */ static void send_break(struct m68k_serial * info, unsigned int duration) { m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; if (!info->port) return; local_irq_save(flags); #ifdef USE_INTS uart->utx.w |= UTX_SEND_BREAK; msleep_interruptible(duration); uart->utx.w &= ~UTX_SEND_BREAK; #endif local_irq_restore(flags); } static int rs_ioctl(struct tty_struct *tty, struct file * file, unsigned int cmd, unsigned long arg) { int error; struct m68k_serial * info = (struct m68k_serial *)tty->driver_data; int retval; if (serial_paranoia_check(info, tty->name, "rs_ioctl")) return -ENODEV; if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) && (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) && (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) { if (tty->flags & (1 << TTY_IO_ERROR)) return -EIO; } switch (cmd) { case TCSBRK: /* SVID version: non-zero arg --> no break */ retval = tty_check_change(tty); if (retval) return retval; tty_wait_until_sent(tty, 0); if (!arg) send_break(info, 250); /* 1/4 second */ return 0; case TCSBRKP: /* support for POSIX tcsendbreak() */ retval = tty_check_change(tty); if (retval) return retval; tty_wait_until_sent(tty, 0); send_break(info, arg ? arg*(100) : 250); return 0; case TIOCGSERIAL: if (access_ok(VERIFY_WRITE, (void *) arg, sizeof(struct serial_struct))) return get_serial_info(info, (struct serial_struct *) arg); return -EFAULT; case TIOCSSERIAL: return set_serial_info(info, (struct serial_struct *) arg); case TIOCSERGETLSR: /* Get line status register */ if (access_ok(VERIFY_WRITE, (void *) arg, sizeof(unsigned int))) return get_lsr_info(info, (unsigned int *) arg); return -EFAULT; case TIOCSERGSTRUCT: if (!access_ok(VERIFY_WRITE, (void *) arg, sizeof(struct m68k_serial))) return -EFAULT; copy_to_user((struct m68k_serial *) arg, info, sizeof(struct m68k_serial)); return 0; default: return -ENOIOCTLCMD; } return 0; } static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios) { struct m68k_serial *info = (struct m68k_serial *)tty->driver_data; change_speed(info); if ((old_termios->c_cflag & CRTSCTS) && !(tty->termios->c_cflag & CRTSCTS)) { tty->hw_stopped = 0; rs_start(tty); } } /* * ------------------------------------------------------------ * rs_close() * * This routine is called when the serial port gets closed. First, we * wait for the last remaining data to be sent. Then, we unlink its * S structure from the interrupt chain if necessary, and we free * that IRQ if nothing is left in the chain. * ------------------------------------------------------------ */ static void rs_close(struct tty_struct *tty, struct file * filp) { struct m68k_serial * info = (struct m68k_serial *)tty->driver_data; m68328_uart *uart = &uart_addr[info->line]; unsigned long flags; if (!info || serial_paranoia_check(info, tty->name, "rs_close")) return; local_irq_save(flags); if (tty_hung_up_p(filp)) { local_irq_restore(flags); return; } if ((tty->count == 1) && (info->count != 1)) { /* * Uh, oh. tty->count is 1, which means that the tty * structure will be freed. Info->count should always * be one in these conditions. If it's greater than * one, we've got real problems, since it means the * serial port won't be shutdown. */ printk("rs_close: bad serial port count; tty->count is 1, " "info->count is %d\n", info->count); info->count = 1; } if (--info->count < 0) { printk("rs_close: bad serial port count for ttyS%d: %d\n", info->line, info->count); info->count = 0; } if (info->count) { local_irq_restore(flags); return; } info->flags |= S_CLOSING; /* * Now we wait for the transmit buffer to clear; and we notify * the line discipline to only process XON/XOFF characters. */ tty->closing = 1; if (info->closing_wait != S_CLOSING_WAIT_NONE) tty_wait_until_sent(tty, info->closing_wait); /* * At this point we stop accepting input. To do this, we * disable the receive line status interrupts, and tell the * interrupt driver to stop checking the data ready bit in the * line status register. */ uart->ustcnt &= ~USTCNT_RXEN; uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK); shutdown(info); rs_flush_buffer(tty); tty_ldisc_flush(tty); tty->closing = 0; info->event = 0; info->port.tty = NULL; #warning "This is not and has never been valid so fix it" #if 0 if (tty->ldisc.num != ldiscs[N_TTY].num) { if (tty->ldisc.close) (tty->ldisc.close)(tty); tty->ldisc = ldiscs[N_TTY]; tty->termios->c_line = N_TTY; if (tty->ldisc.open) (tty->ldisc.open)(tty); } #endif if (info->blocked_open) { if (info->close_delay) { msleep_interruptible(jiffies_to_msecs(info->close_delay)); } wake_up_interruptible(&info->open_wait); } info->flags &= ~(S_NORMAL_ACTIVE|S_CLOSING); wake_up_interruptible(&info->close_wait); local_irq_restore(flags); } /* * rs_hangup() --- called by tty_hangup() when a hangup is signaled. */ void rs_hangup(struct tty_struct *tty) { struct m68k_serial * info = (struct m68k_serial *)tty->driver_data; if (serial_paranoia_check(info, tty->name, "rs_hangup")) return; rs_flush_buffer(tty); shutdown(info); info->event = 0; info->count = 0; info->flags &= ~S_NORMAL_ACTIVE; info->port.tty = NULL; wake_up_interruptible(&info->open_wait); } /* * ------------------------------------------------------------ * rs_open() and friends * ------------------------------------------------------------ */ static int block_til_ready(struct tty_struct *tty, struct file * filp, struct m68k_serial *info) { DECLARE_WAITQUEUE(wait, current); int retval; int do_clocal = 0; /* * If the device is in the middle of being closed, then block * until it's done, and then try again. */ if (info->flags & S_CLOSING) { interruptible_sleep_on(&info->close_wait); #ifdef SERIAL_DO_RESTART if (info->flags & S_HUP_NOTIFY) return -EAGAIN; else return -ERESTARTSYS; #else return -EAGAIN; #endif } /* * If non-blocking mode is set, or the port is not enabled, * then make the check up front and then exit. */ if ((filp->f_flags & O_NONBLOCK) || (tty->flags & (1 << TTY_IO_ERROR))) { info->flags |= S_NORMAL_ACTIVE; return 0; } if (tty->termios->c_cflag & CLOCAL) do_clocal = 1; /* * Block waiting for the carrier detect and the line to become * free (i.e., not in use by the callout). While we are in * this loop, info->count is dropped by one, so that * rs_close() knows when to free things. We restore it upon * exit, either normal or abnormal. */ retval = 0; add_wait_queue(&info->open_wait, &wait); info->count--; info->blocked_open++; while (1) { local_irq_disable(); m68k_rtsdtr(info, 1); local_irq_enable(); current->state = TASK_INTERRUPTIBLE; if (tty_hung_up_p(filp) || !(info->flags & S_INITIALIZED)) { #ifdef SERIAL_DO_RESTART if (info->flags & S_HUP_NOTIFY) retval = -EAGAIN; else retval = -ERESTARTSYS; #else retval = -EAGAIN; #endif break; } if (!(info->flags & S_CLOSING) && do_clocal) break; if (signal_pending(current)) { retval = -ERESTARTSYS; break; } schedule(); } current->state = TASK_RUNNING; remove_wait_queue(&info->open_wait, &wait); if (!tty_hung_up_p(filp)) info->count++; info->blocked_open--; if (retval) return retval; info->flags |= S_NORMAL_ACTIVE; return 0; } /* * This routine is called whenever a serial port is opened. It * enables interrupts for a serial port, linking in its S structure into * the IRQ chain. It also performs the serial-specific * initialization for the tty structure. */ int rs_open(struct tty_struct *tty, struct file * filp) { struct m68k_serial *info; int retval, line; line = tty->index; if (line >= NR_PORTS || line < 0) /* we have exactly one */ return -ENODEV; info = &m68k_soft[line]; if (serial_paranoia_check(info, tty->name, "rs_open")) return -ENODEV; info->count++; tty->driver_data = info; info->port.tty = tty; /* * Start up serial port */ retval = startup(info); if (retval) return retval; return block_til_ready(tty, filp, info); } /* Finally, routines used to initialize the serial driver. */ static void show_serial_version(void) { printk("MC68328 serial driver version 1.00\n"); } static const struct tty_operations rs_ops = { .open = rs_open, .close = rs_close, .write = rs_write, .flush_chars = rs_flush_chars, .write_room = rs_write_room, .chars_in_buffer = rs_chars_in_buffer, .flush_buffer = rs_flush_buffer, .ioctl = rs_ioctl, .throttle = rs_throttle, .unthrottle = rs_unthrottle, .set_termios = rs_set_termios, .stop = rs_stop, .start = rs_start, .hangup = rs_hangup, .set_ldisc = rs_set_ldisc, }; /* rs_init inits the driver */ static int __init rs68328_init(void) { int flags, i; struct m68k_serial *info; serial_driver = alloc_tty_driver(NR_PORTS); if (!serial_driver) return -ENOMEM; show_serial_version(); /* Initialize the tty_driver structure */ /* SPARC: Not all of this is exactly right for us. */ serial_driver->name = "ttyS"; serial_driver->major = TTY_MAJOR; serial_driver->minor_start = 64; serial_driver->type = TTY_DRIVER_TYPE_SERIAL; serial_driver->subtype = SERIAL_TYPE_NORMAL; serial_driver->init_termios = tty_std_termios; serial_driver->init_termios.c_cflag = m68328_console_cbaud | CS8 | CREAD | HUPCL | CLOCAL; serial_driver->flags = TTY_DRIVER_REAL_RAW; tty_set_operations(serial_driver, &rs_ops); if (tty_register_driver(serial_driver)) { put_tty_driver(serial_driver); printk(KERN_ERR "Couldn't register serial driver\n"); return -ENOMEM; } local_irq_save(flags); for(i=0;i<NR_PORTS;i++) { info = &m68k_soft[i]; info->magic = SERIAL_MAGIC; info->port = (int) &uart_addr[i]; info->port.tty = NULL; info->irq = uart_irqs[i]; info->custom_divisor = 16; info->close_delay = 50; info->closing_wait = 3000; info->x_char = 0; info->event = 0; info->count = 0; info->blocked_open = 0; INIT_WORK(&info->tqueue, do_softint); INIT_WORK(&info->tqueue_hangup, do_serial_hangup); init_waitqueue_head(&info->open_wait); init_waitqueue_head(&info->close_wait); info->line = i; info->is_cons = 1; /* Means shortcuts work */ printk("%s%d at 0x%08x (irq = %d)", serial_driver->name, info->line, info->port, info->irq); printk(" is a builtin MC68328 UART\n"); #ifdef CONFIG_M68VZ328 if (i > 0 ) PJSEL &= 0xCF; /* PSW enable second port output */ #endif if (request_irq(uart_irqs[i], rs_interrupt, IRQF_DISABLED, "M68328_UART", info)) panic("Unable to attach 68328 serial interrupt\n"); } local_irq_restore(flags); return 0; } module_init(rs68328_init); static void m68328_set_baud(void) { unsigned short ustcnt; int i; ustcnt = USTCNT; USTCNT = ustcnt & ~USTCNT_TXEN; again: for (i = 0; i < sizeof(baud_table) / sizeof(baud_table[0]); i++) if (baud_table[i] == m68328_console_baud) break; if (i >= sizeof(baud_table) / sizeof(baud_table[0])) { m68328_console_baud = 9600; goto again; } UBAUD = PUT_FIELD(UBAUD_DIVIDE, hw_baud_table[i].divisor) | PUT_FIELD(UBAUD_PRESCALER, hw_baud_table[i].prescale); ustcnt &= ~(USTCNT_PARITYEN | USTCNT_ODD_EVEN | USTCNT_STOP | USTCNT_8_7); ustcnt |= USTCNT_8_7; ustcnt |= USTCNT_TXEN; USTCNT = ustcnt; m68328_console_initted = 1; return; } int m68328_console_setup(struct console *cp, char *arg) { int i, n = CONSOLE_BAUD_RATE; if (!cp) return(-1); if (arg) n = simple_strtoul(arg,NULL,0); for (i = 0; i < BAUD_TABLE_SIZE; i++) if (baud_table[i] == n) break; if (i < BAUD_TABLE_SIZE) { m68328_console_baud = n; m68328_console_cbaud = 0; if (i > 15) { m68328_console_cbaud |= CBAUDEX; i -= 15; } m68328_console_cbaud |= i; } m68328_set_baud(); /* make sure baud rate changes */ return(0); } static struct tty_driver *m68328_console_device(struct console *c, int *index) { *index = c->index; return serial_driver; } void m68328_console_write (struct console *co, const char *str, unsigned int count) { if (!m68328_console_initted) m68328_set_baud(); while (count--) { if (*str == '\n') rs_put_char('\r'); rs_put_char( *str++ ); } } static struct console m68328_driver = { .name = "ttyS", .write = m68328_console_write, .device = m68328_console_device, .setup = m68328_console_setup, .flags = CON_PRINTBUFFER, .index = -1, }; static int __init m68328_console_init(void) { register_console(&m68328_driver); return 0; } console_initcall(m68328_console_init);