/* * drivers/char/serial_tx3912.c * * Copyright (C) 2001 Steven J. Hill (sjhill@realitydiluted.com) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Serial driver for TMPR3912/05 and PR31700 processors */ #include #include #include #include #include #include #include #include #include #include #include #include #include "serial_tx3912.h" /* * Forward declarations for serial routines */ static void rs_disable_tx_interrupts (void * ptr); static void rs_enable_tx_interrupts (void * ptr); static void rs_disable_rx_interrupts (void * ptr); static void rs_enable_rx_interrupts (void * ptr); static int rs_get_CD (void * ptr); static void rs_shutdown_port (void * ptr); static int rs_set_real_termios (void *ptr); static int rs_chars_in_buffer (void * ptr); static void rs_hungup (void *ptr); static void rs_close (void *ptr); /* * Used by generic serial driver to access hardware */ static struct real_driver rs_real_driver = { disable_tx_interrupts: rs_disable_tx_interrupts, enable_tx_interrupts: rs_enable_tx_interrupts, disable_rx_interrupts: rs_disable_rx_interrupts, enable_rx_interrupts: rs_enable_rx_interrupts, get_CD: rs_get_CD, shutdown_port: rs_shutdown_port, set_real_termios: rs_set_real_termios, chars_in_buffer: rs_chars_in_buffer, close: rs_close, hungup: rs_hungup, }; /* * Structures and usage counts */ static struct tty_driver rs_driver, rs_callout_driver; static struct tty_struct **rs_tty; static struct termios **rs_termios; static struct termios **rs_termios_locked; static struct rs_port *rs_port; static int rs_refcount; static int rs_initialized; /* * Receive a character */ static inline void receive_char_pio(struct rs_port *port) { struct tty_struct *tty = port->gs.tty; unsigned char ch; int counter = 2048; /* While there are characters */ while (counter > 0) { if (!(inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_RXHOLDFULL)) break; ch = inb(TX3912_UARTA_DATA); if (tty->flip.count < TTY_FLIPBUF_SIZE) { *tty->flip.char_buf_ptr++ = ch; *tty->flip.flag_buf_ptr++ = 0; tty->flip.count++; } udelay(1); counter--; } tty_flip_buffer_push(tty); } /* * Transmit a character */ static inline void transmit_char_pio(struct rs_port *port) { /* TX while bytes available */ for (;;) { if (!(inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_EMPTY)) break; else if (port->x_char) { outb(port->x_char, TX3912_UARTA_DATA); port->icount.tx++; port->x_char = 0; } else if (port->gs.xmit_cnt <= 0 || port->gs.tty->stopped || port->gs.tty->hw_stopped) { break; } else { outb(port->gs.xmit_buf[port->gs.xmit_tail++], TX3912_UARTA_DATA); port->icount.tx++; port->gs.xmit_tail &= SERIAL_XMIT_SIZE-1; if (--port->gs.xmit_cnt <= 0) { break; } } udelay(10); } if (port->gs.xmit_cnt <= 0 || port->gs.tty->stopped || port->gs.tty->hw_stopped) { rs_disable_tx_interrupts(port); } if (port->gs.xmit_cnt <= port->gs.wakeup_chars) { if ((port->gs.tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && port->gs.tty->ldisc.write_wakeup) (port->gs.tty->ldisc.write_wakeup)(port->gs.tty); rs_dprintk(TX3912_UART_DEBUG_TRANSMIT, "Waking up.... ldisc (%d)....\n", port->gs.wakeup_chars); wake_up_interruptible(&port->gs.tty->write_wait); } } /* * We don't have MSR */ static inline void check_modem_status(struct rs_port *port) { wake_up_interruptible(&port->gs.open_wait); } /* * RX interrupt handler */ static inline void rs_rx_interrupt(int irq, void *dev_id, struct pt_regs *regs) { unsigned long flags, status; save_and_cli(flags); rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "rs_rx_interrupt..."); /* Get the interrupts */ status = inl(TX3912_INT2_STATUS); /* Clear any interrupts we might be about to handle */ outl(TX3912_INT2_UARTA_RX_BITS, TX3912_INT2_CLEAR); if(!rs_port || !rs_port->gs.tty) { restore_flags(flags); return; } /* RX Receiver Holding Register Overrun */ if(status & TX3912_INT2_UARTATXOVERRUNINT) { rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "overrun"); rs_port->icount.overrun++; } /* RX Frame Error */ if(status & TX3912_INT2_UARTAFRAMEERRINT) { rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "frame error"); rs_port->icount.frame++; } /* Break signal received */ if(status & TX3912_INT2_UARTABREAKINT) { rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "break"); rs_port->icount.brk++; } /* RX Parity Error */ if(status & TX3912_INT2_UARTAPARITYINT) { rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "parity error"); rs_port->icount.parity++; } /* Byte received */ if(status & TX3912_INT2_UARTARXINT) { receive_char_pio(rs_port); } restore_flags(flags); rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "end.\n"); } /* * TX interrupt handler */ static inline void rs_tx_interrupt(int irq, void *dev_id, struct pt_regs *regs) { unsigned long flags, status; save_and_cli(flags); rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "rs_tx_interrupt..."); /* Get the interrupts */ status = inl(TX3912_INT2_STATUS); if(!rs_port || !rs_port->gs.tty) { restore_flags(flags); return; } /* Clear interrupts */ outl(TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_CLEAR); /* TX holding register empty - transmit a byte */ if(status & TX3912_INT2_UARTAEMPTYINT) { transmit_char_pio(rs_port); } /* TX Transmit Holding Register Overrun (shouldn't happen) */ if(status & TX3912_INT2_UARTATXOVERRUNINT) { printk( "rs_tx_interrupt: TX overrun\n"); } restore_flags(flags); rs_dprintk(TX3912_UART_DEBUG_INTERRUPTS, "end.\n"); } /* * Here are the routines that actually interface with the generic driver */ static void rs_disable_tx_interrupts (void * ptr) { unsigned long flags; save_and_cli(flags); outl(inl(TX3912_INT2_ENABLE) & ~TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_ENABLE); outl(TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_CLEAR); restore_flags(flags); } static void rs_enable_tx_interrupts (void * ptr) { unsigned long flags; save_and_cli(flags); outl(TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_CLEAR); outl(inl(TX3912_INT2_ENABLE) | TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_ENABLE); transmit_char_pio(rs_port); restore_flags(flags); } static void rs_disable_rx_interrupts (void * ptr) { unsigned long flags; save_and_cli(flags); outl(inl(TX3912_INT2_ENABLE) & ~TX3912_INT2_UARTA_RX_BITS, TX3912_INT2_ENABLE); outl(TX3912_INT2_UARTA_RX_BITS, TX3912_INT2_CLEAR); restore_flags(flags); } static void rs_enable_rx_interrupts (void * ptr) { unsigned long flags; save_and_cli(flags); outl(inl(TX3912_INT2_ENABLE) | TX3912_INT2_UARTA_RX_BITS, TX3912_INT2_ENABLE); while (inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_RXHOLDFULL) inb(TX3912_UARTA_DATA); outl(TX3912_INT2_UARTA_RX_BITS, TX3912_INT2_CLEAR); restore_flags(flags); } /* * We have no CD */ static int rs_get_CD (void * ptr) { return 1; } /* * Shut down the port */ static void rs_shutdown_port (void * ptr) { func_enter(); rs_port->gs.flags &= ~GS_ACTIVE; func_exit(); } static int rs_set_real_termios (void *ptr) { unsigned int ctrl1 = 0; unsigned int ctrl2 = 0; /* Set baud rate */ switch (rs_port->gs.baud) { case 0: goto done; case 1200: ctrl2 = TX3912_UART_CTRL2_B1200; break; case 2400: ctrl2 = TX3912_UART_CTRL2_B2400; break; case 4800: ctrl2 = TX3912_UART_CTRL2_B4800; break; case 9600: ctrl2 = TX3912_UART_CTRL2_B9600; break; case 19200: ctrl2 = TX3912_UART_CTRL2_B19200; break; case 38400: ctrl2 = TX3912_UART_CTRL2_B38400; break; case 57600: ctrl2 = TX3912_UART_CTRL2_B57600; break; case 115200: default: ctrl2 = TX3912_UART_CTRL2_B115200; break; } /* Clear current UARTA settings */ ctrl1 = inl(TX3912_UARTA_CTRL1) & 0xf000000f; /* Set parity */ if(C_PARENB(rs_port->gs.tty)) { if (!C_PARODD(rs_port->gs.tty)) ctrl1 |= (TX3912_UART_CTRL1_ENPARITY | TX3912_UART_CTRL1_EVENPARITY); else ctrl1 |= TX3912_UART_CTRL1_ENPARITY; } /* Set data size */ switch(rs_port->gs.tty->termios->c_cflag & CSIZE) { case CS7: ctrl1 |= TX3912_UART_CTRL1_BIT_7; break; case CS5: case CS6: printk(KERN_ERR "Data byte size unsupported. Defaulting to CS8\n"); case CS8: default: ctrl1 &= ~TX3912_UART_CTRL1_BIT_7; } /* Set stop bits */ if(C_CSTOPB(rs_port->gs.tty)) ctrl1 |= TX3912_UART_CTRL1_TWOSTOP; /* Write the control registers */ outl(ctrl2, TX3912_UARTA_CTRL2); outl(0, TX3912_UARTA_DMA_CTRL1); outl(0, TX3912_UARTA_DMA_CTRL2); outl(ctrl1, TX3912_UARTA_CTRL1); /* Loop until the UART is on */ while(~inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_UARTON); done: func_exit(); return 0; } /* * Anyone in the buffer? */ static int rs_chars_in_buffer (void * ptr) { return ((inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_EMPTY) ? 0 : 1); } /* * Open the serial port */ static int rs_open(struct tty_struct * tty, struct file * filp) { int retval; func_enter(); if(!rs_initialized) { return -EIO; } if(MINOR(tty->device) - tty->driver.minor_start) { return -ENODEV; } rs_dprintk(TX3912_UART_DEBUG_OPEN, "Serial opening...\n"); tty->driver_data = rs_port; rs_port->gs.tty = tty; rs_port->gs.count++; /* * Start up serial port */ retval = gs_init_port(&rs_port->gs); rs_dprintk(TX3912_UART_DEBUG_OPEN, "Finished gs_init...\n"); if(retval) { rs_port->gs.count--; return retval; } rs_port->gs.flags |= GS_ACTIVE; if(rs_port->gs.count == 1) { MOD_INC_USE_COUNT; } rs_enable_rx_interrupts(rs_port); rs_enable_tx_interrupts(rs_port); retval = gs_block_til_ready(&rs_port->gs, filp); if(retval) { MOD_DEC_USE_COUNT; rs_port->gs.count--; return retval; } if((rs_port->gs.count == 1) && (rs_port->gs.flags & ASYNC_SPLIT_TERMIOS)) { if (tty->driver.subtype == SERIAL_TYPE_NORMAL) *tty->termios = rs_port->gs.normal_termios; else *tty->termios = rs_port->gs.callout_termios; rs_set_real_termios(rs_port); } rs_port->gs.session = current->session; rs_port->gs.pgrp = current->pgrp; func_exit(); return 0; } /* * Close the serial port */ static void rs_close(void *ptr) { func_enter(); MOD_DEC_USE_COUNT; func_exit(); } /* * Hang up the serial port */ static void rs_hungup(void *ptr) { func_enter(); MOD_DEC_USE_COUNT; func_exit(); } /* * Serial ioctl call */ static int rs_ioctl(struct tty_struct * tty, struct file * filp, unsigned int cmd, unsigned long arg) { int ival, rc; rc = 0; switch (cmd) { case TIOCGSOFTCAR: rc = put_user((tty->termios->c_cflag & CLOCAL) ? 1 : 0, (unsigned int *) arg); break; case TIOCSSOFTCAR: if ((rc = verify_area(VERIFY_READ, (void *) arg, sizeof(int))) == 0) { get_user(ival, (unsigned int *) arg); tty->termios->c_cflag = (tty->termios->c_cflag & ~CLOCAL) | (ival ? CLOCAL : 0); } break; case TIOCGSERIAL: if ((rc = verify_area(VERIFY_WRITE, (void *) arg, sizeof(struct serial_struct))) == 0) rc = gs_getserial(&rs_port->gs, (struct serial_struct *) arg); break; case TIOCSSERIAL: if ((rc = verify_area(VERIFY_READ, (void *) arg, sizeof(struct serial_struct))) == 0) rc = gs_setserial(&rs_port->gs, (struct serial_struct *) arg); break; default: rc = -ENOIOCTLCMD; break; } return rc; } /* * Send xchar */ static void rs_send_xchar(struct tty_struct * tty, char ch) { func_enter(); rs_port->x_char = ch; if (ch) { rs_enable_tx_interrupts(tty); } func_exit(); } /* * Throttle characters as directed by upper tty layer */ static void rs_throttle(struct tty_struct * tty) { #ifdef TX3912_UART_DEBUG_THROTTLE char buf[64]; printk("throttle %s: %d....\n", tty_name(tty, buf), tty->ldisc.chars_in_buffer(tty)); #endif func_enter(); if (I_IXOFF(tty)) rs_send_xchar(tty, STOP_CHAR(tty)); func_exit(); } /* * Un-throttle characters as directed by upper tty layer */ static void rs_unthrottle(struct tty_struct * tty) { #ifdef TX3912_UART_DEBUG_THROTTLE char buf[64]; printk("unthrottle %s: %d....\n", tty_name(tty, buf), tty->ldisc.chars_in_buffer(tty)); #endif func_enter(); if (I_IXOFF(tty)) { if (rs_port->x_char) rs_port->x_char = 0; else rs_send_xchar(tty, START_CHAR(tty)); } func_exit(); } /* * Initialize the serial port */ void __init tx3912_rs_init(void) { func_enter(); rs_dprintk(TX3912_UART_DEBUG_INIT, "Initializing serial...\n"); /* Allocate critical structures */ if(!(rs_tty = kmalloc(sizeof(struct tty_struct), GFP_KERNEL))) { return; } if(!(rs_port = kmalloc(sizeof(struct rs_port), GFP_KERNEL))) { kfree(rs_tty); return; } if(!(rs_termios = kmalloc(sizeof(struct termios), GFP_KERNEL))) { kfree(rs_port); kfree(rs_tty); return; } if(!(rs_termios_locked = kmalloc(sizeof(struct termios), GFP_KERNEL))) { kfree(rs_termios); kfree(rs_port); kfree(rs_tty); return; } /* Zero out the structures */ memset(rs_tty, 0, sizeof(struct tty_struct)); memset(rs_port, 0, sizeof(struct rs_port)); memset(rs_termios, 0, sizeof(struct termios)); memset(rs_termios_locked, 0, sizeof(struct termios)); memset(&rs_driver, 0, sizeof(rs_driver)); memset(&rs_callout_driver, 0, sizeof(rs_callout_driver)); /* Fill in hardware specific port structure */ rs_port->gs.callout_termios = tty_std_termios; rs_port->gs.normal_termios = tty_std_termios; rs_port->gs.magic = SERIAL_MAGIC; rs_port->gs.close_delay = HZ/2; rs_port->gs.closing_wait = 30 * HZ; rs_port->gs.rd = &rs_real_driver; #ifdef NEW_WRITE_LOCKING rs_port->gs.port_write_sem = MUTEX; #endif #ifdef DECLARE_WAITQUEUE init_waitqueue_head(&rs_port->gs.open_wait); init_waitqueue_head(&rs_port->gs.close_wait); #endif /* Fill in generic serial driver structures */ rs_driver.magic = TTY_DRIVER_MAGIC; rs_driver.driver_name = "serial"; rs_driver.name = "ttyS"; rs_driver.major = TTY_MAJOR; rs_driver.minor_start = 64; rs_driver.num = 1; rs_driver.type = TTY_DRIVER_TYPE_SERIAL; rs_driver.subtype = SERIAL_TYPE_NORMAL; rs_driver.init_termios = tty_std_termios; rs_driver.init_termios.c_cflag = B115200 | CS8 | CREAD | HUPCL | CLOCAL; rs_driver.refcount = &rs_refcount; rs_driver.table = rs_tty; rs_driver.termios = rs_termios; rs_driver.termios_locked = rs_termios_locked; rs_driver.open = rs_open; rs_driver.close = gs_close; rs_driver.write = gs_write; rs_driver.put_char = gs_put_char; rs_driver.flush_chars = gs_flush_chars; rs_driver.write_room = gs_write_room; rs_driver.chars_in_buffer = gs_chars_in_buffer; rs_driver.flush_buffer = gs_flush_buffer; rs_driver.ioctl = rs_ioctl; rs_driver.throttle = rs_throttle; rs_driver.unthrottle = rs_unthrottle; rs_driver.set_termios = gs_set_termios; rs_driver.stop = gs_stop; rs_driver.start = gs_start; rs_driver.hangup = gs_hangup; rs_callout_driver = rs_driver; rs_callout_driver.name = "cua"; rs_callout_driver.major = TTYAUX_MAJOR; rs_callout_driver.subtype = SERIAL_TYPE_CALLOUT; /* Register serial and callout drivers */ if(tty_register_driver(&rs_driver)) { printk(KERN_ERR "Unable to register serial driver\n"); goto error; } if(tty_register_driver(&rs_callout_driver)) { tty_unregister_driver(&rs_driver); printk(KERN_ERR "Unable to register callout driver\n"); goto error; } /* Assign IRQs */ if(request_irq(2, rs_tx_interrupt, SA_SHIRQ, "uarta_tx", rs_port)) { printk(KERN_ERR "Cannot allocate IRQ for UARTA_TX.\n"); goto error; } if(request_irq(3, rs_rx_interrupt, SA_SHIRQ, "uarta_rx", rs_port)) { printk(KERN_ERR "Cannot allocate IRQ for UARTA_RX.\n"); goto error; } /* Enable the serial receive interrupt */ rs_enable_rx_interrupts(rs_port); #ifndef CONFIG_SERIAL_TX3912_CONSOLE /* Write the control registers */ outl(TX3912_UART_CTRL2_B115200, TX3912_UARTA_CTRL2); outl(0x00000000, TX3912_UARTA_DMA_CTRL1); outl(0x00000000, TX3912_UARTA_DMA_CTRL2); outl(inl(TX3912_UARTA_CTRL1) | TX3912_UART_CTRL1_ENUART, TX3912_UARTA_CTRL1); /* Loop until the UART is on */ while(~inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_UARTON); #endif rs_initialized = 1; func_exit(); return; error: kfree(rs_termios_locked); kfree(rs_termios); kfree(rs_port); kfree(rs_tty); func_exit(); } /* * Begin serial console routines */ #ifdef CONFIG_SERIAL_TX3912_CONSOLE void serial_outc(unsigned char c) { int i; unsigned long int2; /* Disable UARTA_TX interrupts */ int2 = inl(TX3912_INT2_ENABLE); outl(inl(TX3912_INT2_ENABLE) & ~TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_ENABLE); /* Wait for UARTA_TX register to empty */ i = 10000; while(!(inl(TX3912_INT2_STATUS) & TX3912_INT2_UARTATXINT) && i--); outl(TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_CLEAR); /* Send the character */ outl(c, TX3912_UARTA_DATA); /* Wait for UARTA_TX register to empty */ i = 10000; while(!(inl(TX3912_INT2_STATUS) & TX3912_INT2_UARTATXINT) && i--); outl(TX3912_INT2_UARTA_TX_BITS, TX3912_INT2_CLEAR); /* Enable UARTA_TX interrupts */ outl(int2, TX3912_INT2_ENABLE); } static int serial_console_wait_key(struct console *co) { unsigned int int2, res; int2 = inl(TX3912_INT2_ENABLE); outl(0, TX3912_INT2_ENABLE); while (!(inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_RXHOLDFULL)); res = inl(TX3912_UARTA_DATA); udelay(10); outl(int2, TX3912_INT2_ENABLE); return res; } static void serial_console_write(struct console *co, const char *s, unsigned count) { unsigned int i; for (i = 0; i < count; i++) { if (*s == '\n') serial_outc('\r'); serial_outc(*s++); } } static kdev_t serial_console_device(struct console *c) { return MKDEV(TTY_MAJOR, 64 + c->index); } static __init int serial_console_setup(struct console *co, char *options) { int baud = 115200; int bits = 8; int parity = 'n'; char *s; unsigned int ctrl1 = 0; unsigned int ctrl2 = 0; if (options) { baud = simple_strtoul(options, NULL, 10); s = options; while(*s >= '0' && *s <= '9') s++; if (*s) parity = *s++; if (*s) bits = *s++ - '0'; } switch(baud) { case 1200: ctrl2 = TX3912_UART_CTRL2_B1200; break; case 2400: ctrl2 = TX3912_UART_CTRL2_B2400; break; case 4800: ctrl2 = TX3912_UART_CTRL2_B4800; break; case 9600: ctrl2 = TX3912_UART_CTRL2_B9600; break; case 19200: ctrl2 = TX3912_UART_CTRL2_B19200; break; case 38400: ctrl2 = TX3912_UART_CTRL2_B38400; break; case 57600: ctrl2 = TX3912_UART_CTRL2_B57600; break; case 115200: default: ctrl2 = TX3912_UART_CTRL2_B115200; break; } switch(bits) { case 7: ctrl1 = TX3912_UART_CTRL1_BIT_7; break; default: break; } switch(parity) { case 'o': case 'O': ctrl1 |= TX3912_UART_CTRL1_ENPARITY; break; case 'e': case 'E': ctrl1 |= (TX3912_UART_CTRL1_ENPARITY | TX3912_UART_CTRL1_EVENPARITY); break; default: break; } /* Write the control registers */ outl(ctrl2, TX3912_UARTA_CTRL2); outl(0x00000000, TX3912_UARTA_DMA_CTRL1); outl(0x00000000, TX3912_UARTA_DMA_CTRL2); outl((ctrl1 | TX3912_UART_CTRL1_ENUART), TX3912_UARTA_CTRL1); /* Loop until the UART is on */ while(~inl(TX3912_UARTA_CTRL1) & TX3912_UART_CTRL1_UARTON); return 0; } static struct console sercons = { name: "ttyS", write: serial_console_write, device: serial_console_device, wait_key: serial_console_wait_key, setup: serial_console_setup, flags: CON_PRINTBUFFER, index: -1 }; void __init tx3912_console_init(void) { register_console(&sercons); } #endif