diff options
Diffstat (limited to 'drivers/tty/amiserial.c')
| -rw-r--r-- | drivers/tty/amiserial.c | 1662 |
1 files changed, 1662 insertions, 0 deletions
diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c new file mode 100644 index 0000000000..785558c65a --- /dev/null +++ b/drivers/tty/amiserial.c @@ -0,0 +1,1662 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Serial driver for the amiga builtin port. + * + * This code was created by taking serial.c version 4.30 from kernel + * release 2.3.22, replacing all hardware related stuff with the + * corresponding amiga hardware actions, and removing all irrelevant + * code. As a consequence, it uses many of the constants and names + * associated with the registers and bits of 16550 compatible UARTS - + * but only to keep track of status, etc in the state variables. It + * was done this was to make it easier to keep the code in line with + * (non hardware specific) changes to serial.c. + * + * The port is registered with the tty driver as minor device 64, and + * therefore other ports should only use 65 upwards. + * + * Richard Lucock 28/12/99 + * + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, + * 1998, 1999 Theodore Ts'o + * + */ + +/* Set of debugging defines */ + +#undef SERIAL_DEBUG_INTR +#undef SERIAL_DEBUG_OPEN +#undef SERIAL_DEBUG_FLOW +#undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT + +/* + * End of serial driver configuration section. + */ + +#include <linux/bitops.h> +#include <linux/circ_buf.h> +#include <linux/console.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/fcntl.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/major.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/ptrace.h> +#include <linux/seq_file.h> +#include <linux/serial.h> +#include <linux/serial_reg.h> +#include <linux/serial_core.h> +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/timer.h> +#include <linux/tty_flip.h> +#include <linux/tty.h> +#include <linux/types.h> +#include <linux/uaccess.h> + +#include <asm/amigahw.h> +#include <asm/amigaints.h> +#include <asm/irq.h> +#include <asm/setup.h> + +struct serial_state { + struct tty_port tport; + struct circ_buf xmit; + struct async_icount icount; + + unsigned long port; + int baud_base; + int custom_divisor; + int read_status_mask; + int ignore_status_mask; + int timeout; + int quot; + int IER; /* Interrupt Enable Register */ + int MCR; /* Modem control register */ + int x_char; /* xon/xoff character */ +}; + +static struct tty_driver *serial_driver; + +/* number of characters left in xmit buffer before we ask for more */ +#define WAKEUP_CHARS 256 + +#define XMIT_FIFO_SIZE 1 + +static unsigned char current_ctl_bits; + +static void change_speed(struct tty_struct *tty, struct serial_state *info, + const struct ktermios *old); +static void rs_wait_until_sent(struct tty_struct *tty, int timeout); + + +static struct serial_state serial_state; + +/* some serial hardware definitions */ +#define SDR_OVRUN (1<<15) +#define SDR_RBF (1<<14) +#define SDR_TBE (1<<13) +#define SDR_TSRE (1<<12) + +#define SERPER_PARENB (1<<15) + +#define AC_SETCLR (1<<15) +#define AC_UARTBRK (1<<11) + +#define SER_DTR (1<<7) +#define SER_RTS (1<<6) +#define SER_DCD (1<<5) +#define SER_CTS (1<<4) +#define SER_DSR (1<<3) + +static __inline__ void rtsdtr_ctrl(int bits) +{ + ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR)); +} + +/* + * ------------------------------------------------------------ + * rs_stop() and rs_start() + * + * This routines are called before setting or resetting tty->flow.stopped. + * They enable or disable transmitter interrupts, as necessary. + * ------------------------------------------------------------ + */ +static void rs_stop(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; + + local_irq_save(flags); + if (info->IER & UART_IER_THRI) { + info->IER &= ~UART_IER_THRI; + /* disable Tx interrupt and remove any pending interrupts */ + amiga_custom.intena = IF_TBE; + mb(); + amiga_custom.intreq = IF_TBE; + mb(); + } + local_irq_restore(flags); +} + +static void rs_start(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; + + local_irq_save(flags); + if (info->xmit.head != info->xmit.tail + && info->xmit.buf + && !(info->IER & UART_IER_THRI)) { + info->IER |= UART_IER_THRI; + amiga_custom.intena = IF_SETCLR | IF_TBE; + mb(); + /* set a pending Tx Interrupt, transmitter should restart now */ + amiga_custom.intreq = IF_SETCLR | IF_TBE; + mb(); + } + local_irq_restore(flags); +} + +/* + * ---------------------------------------------------------------------- + * + * Here start the interrupt handling routines. + * + * ----------------------------------------------------------------------- + */ + +static void receive_chars(struct serial_state *info) +{ + int status; + int serdatr; + unsigned char ch, flag; + struct async_icount *icount; + int oe = 0; + + icount = &info->icount; + + status = UART_LSR_DR; /* We obviously have a character! */ + serdatr = amiga_custom.serdatr; + mb(); + amiga_custom.intreq = IF_RBF; + mb(); + + if((serdatr & 0x1ff) == 0) + status |= UART_LSR_BI; + if(serdatr & SDR_OVRUN) + status |= UART_LSR_OE; + + ch = serdatr & 0xff; + icount->rx++; + +#ifdef SERIAL_DEBUG_INTR + printk("DR%02x:%02x...", ch, status); +#endif + flag = TTY_NORMAL; + + /* + * We don't handle parity or frame errors - but I have left + * the code in, since I'm not sure that the errors can't be + * detected. + */ + + if (status & (UART_LSR_BI | UART_LSR_PE | + UART_LSR_FE | UART_LSR_OE)) { + /* + * For statistics only + */ + if (status & UART_LSR_BI) { + status &= ~(UART_LSR_FE | UART_LSR_PE); + icount->brk++; + } else if (status & UART_LSR_PE) + icount->parity++; + else if (status & UART_LSR_FE) + icount->frame++; + if (status & UART_LSR_OE) + icount->overrun++; + + /* + * Now check to see if character should be + * ignored, and mask off conditions which + * should be ignored. + */ + if (status & info->ignore_status_mask) + goto out; + + status &= info->read_status_mask; + + if (status & (UART_LSR_BI)) { +#ifdef SERIAL_DEBUG_INTR + printk("handling break...."); +#endif + flag = TTY_BREAK; + if (info->tport.flags & ASYNC_SAK) + do_SAK(info->tport.tty); + } else if (status & UART_LSR_PE) + flag = TTY_PARITY; + else if (status & UART_LSR_FE) + flag = TTY_FRAME; + if (status & UART_LSR_OE) { + /* + * Overrun is special, since it's + * reported immediately, and doesn't + * affect the current character + */ + oe = 1; + } + } + tty_insert_flip_char(&info->tport, ch, flag); + if (oe == 1) + tty_insert_flip_char(&info->tport, 0, TTY_OVERRUN); + tty_flip_buffer_push(&info->tport); +out: + return; +} + +static void transmit_chars(struct serial_state *info) +{ + amiga_custom.intreq = IF_TBE; + mb(); + if (info->x_char) { + amiga_custom.serdat = info->x_char | 0x100; + mb(); + info->icount.tx++; + info->x_char = 0; + return; + } + if (info->xmit.head == info->xmit.tail + || info->tport.tty->flow.stopped + || info->tport.tty->hw_stopped) { + info->IER &= ~UART_IER_THRI; + amiga_custom.intena = IF_TBE; + mb(); + return; + } + + amiga_custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100; + mb(); + info->xmit.tail = info->xmit.tail & (UART_XMIT_SIZE - 1); + info->icount.tx++; + + if (CIRC_CNT(info->xmit.head, + info->xmit.tail, + UART_XMIT_SIZE) < WAKEUP_CHARS) + tty_wakeup(info->tport.tty); + +#ifdef SERIAL_DEBUG_INTR + printk("THRE..."); +#endif + if (info->xmit.head == info->xmit.tail) { + amiga_custom.intena = IF_TBE; + mb(); + info->IER &= ~UART_IER_THRI; + } +} + +static void check_modem_status(struct serial_state *info) +{ + struct tty_port *port = &info->tport; + unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR); + unsigned char dstatus; + struct async_icount *icount; + + /* Determine bits that have changed */ + dstatus = status ^ current_ctl_bits; + current_ctl_bits = status; + + if (dstatus) { + icount = &info->icount; + /* update input line counters */ + if (dstatus & SER_DSR) + icount->dsr++; + if (dstatus & SER_DCD) { + icount->dcd++; + } + if (dstatus & SER_CTS) + icount->cts++; + wake_up_interruptible(&port->delta_msr_wait); + } + + if (tty_port_check_carrier(port) && (dstatus & SER_DCD)) { +#if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR)) + printk("ttyS%d CD now %s...", info->line, + (!(status & SER_DCD)) ? "on" : "off"); +#endif + if (!(status & SER_DCD)) + wake_up_interruptible(&port->open_wait); + else { +#ifdef SERIAL_DEBUG_OPEN + printk("doing serial hangup..."); +#endif + if (port->tty) + tty_hangup(port->tty); + } + } + if (tty_port_cts_enabled(port)) { + if (port->tty->hw_stopped) { + if (!(status & SER_CTS)) { +#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW)) + printk("CTS tx start..."); +#endif + port->tty->hw_stopped = false; + info->IER |= UART_IER_THRI; + amiga_custom.intena = IF_SETCLR | IF_TBE; + mb(); + /* set a pending Tx Interrupt, transmitter should restart now */ + amiga_custom.intreq = IF_SETCLR | IF_TBE; + mb(); + tty_wakeup(port->tty); + return; + } + } else { + if ((status & SER_CTS)) { +#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW)) + printk("CTS tx stop..."); +#endif + port->tty->hw_stopped = true; + info->IER &= ~UART_IER_THRI; + /* disable Tx interrupt and remove any pending interrupts */ + amiga_custom.intena = IF_TBE; + mb(); + amiga_custom.intreq = IF_TBE; + mb(); + } + } + } +} + +static irqreturn_t ser_vbl_int( int irq, void *data) +{ + /* vbl is just a periodic interrupt we tie into to update modem status */ + struct serial_state *info = data; + /* + * TBD - is it better to unregister from this interrupt or to + * ignore it if MSI is clear ? + */ + if(info->IER & UART_IER_MSI) + check_modem_status(info); + return IRQ_HANDLED; +} + +static irqreturn_t ser_rx_int(int irq, void *dev_id) +{ + struct serial_state *info = dev_id; + +#ifdef SERIAL_DEBUG_INTR + printk("ser_rx_int..."); +#endif + + if (!info->tport.tty) + return IRQ_NONE; + + receive_chars(info); +#ifdef SERIAL_DEBUG_INTR + printk("end.\n"); +#endif + return IRQ_HANDLED; +} + +static irqreturn_t ser_tx_int(int irq, void *dev_id) +{ + struct serial_state *info = dev_id; + + if (amiga_custom.serdatr & SDR_TBE) { +#ifdef SERIAL_DEBUG_INTR + printk("ser_tx_int..."); +#endif + + if (!info->tport.tty) + return IRQ_NONE; + + transmit_chars(info); +#ifdef SERIAL_DEBUG_INTR + printk("end.\n"); +#endif + } + return IRQ_HANDLED; +} + +/* + * ------------------------------------------------------------------- + * Here ends the serial interrupt routines. + * ------------------------------------------------------------------- + */ + +/* + * --------------------------------------------------------------- + * Low level utility subroutines for the serial driver: routines to + * figure out the appropriate timeout for an interrupt chain, routines + * to initialize and startup a serial port, and routines to shutdown a + * serial port. Useful stuff like that. + * --------------------------------------------------------------- + */ + +static int startup(struct tty_struct *tty, struct serial_state *info) +{ + struct tty_port *port = &info->tport; + unsigned long flags; + int retval=0; + unsigned long page; + + page = get_zeroed_page(GFP_KERNEL); + if (!page) + return -ENOMEM; + + local_irq_save(flags); + + if (tty_port_initialized(port)) { + free_page(page); + goto errout; + } + + if (info->xmit.buf) + free_page(page); + else + info->xmit.buf = (unsigned char *) page; + +#ifdef SERIAL_DEBUG_OPEN + printk("starting up ttys%d ...", info->line); +#endif + + /* Clear anything in the input buffer */ + + amiga_custom.intreq = IF_RBF; + mb(); + + retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info); + if (retval) { + if (capable(CAP_SYS_ADMIN)) { + set_bit(TTY_IO_ERROR, &tty->flags); + retval = 0; + } + goto errout; + } + + /* enable both Rx and Tx interrupts */ + amiga_custom.intena = IF_SETCLR | IF_RBF | IF_TBE; + mb(); + info->IER = UART_IER_MSI; + + /* remember current state of the DCD and CTS bits */ + current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR); + + info->MCR = 0; + if (C_BAUD(tty)) + info->MCR = SER_DTR | SER_RTS; + rtsdtr_ctrl(info->MCR); + + clear_bit(TTY_IO_ERROR, &tty->flags); + info->xmit.head = info->xmit.tail = 0; + + /* + * and set the speed of the serial port + */ + change_speed(tty, info, NULL); + + tty_port_set_initialized(port, true); + local_irq_restore(flags); + return 0; + +errout: + local_irq_restore(flags); + return retval; +} + +/* + * 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 tty_struct *tty, struct serial_state *info) +{ + unsigned long flags; + + if (!tty_port_initialized(&info->tport)) + return; + +#ifdef SERIAL_DEBUG_OPEN + printk("Shutting down serial port %d ....\n", info->line); +#endif + + local_irq_save(flags); /* Disable interrupts */ + + /* + * clear delta_msr_wait queue to avoid mem leaks: we may free the irq + * here so the queue might never be waken up + */ + wake_up_interruptible(&info->tport.delta_msr_wait); + + /* + * Free the IRQ, if necessary + */ + free_irq(IRQ_AMIGA_VERTB, info); + + free_page((unsigned long)info->xmit.buf); + info->xmit.buf = NULL; + + info->IER = 0; + amiga_custom.intena = IF_RBF | IF_TBE; + mb(); + + /* disable break condition */ + amiga_custom.adkcon = AC_UARTBRK; + mb(); + + if (C_HUPCL(tty)) + info->MCR &= ~(SER_DTR|SER_RTS); + rtsdtr_ctrl(info->MCR); + + set_bit(TTY_IO_ERROR, &tty->flags); + + tty_port_set_initialized(&info->tport, false); + local_irq_restore(flags); +} + + +/* + * 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 tty_struct *tty, struct serial_state *info, + const struct ktermios *old_termios) +{ + struct tty_port *port = &info->tport; + int quot = 0, baud_base, baud; + unsigned cflag, cval = 0; + int bits; + unsigned long flags; + + cflag = tty->termios.c_cflag; + + /* Byte size is always 8 bits plus parity bit if requested */ + + cval = 3; bits = 10; + if (cflag & CSTOPB) { + cval |= 0x04; + bits++; + } + if (cflag & PARENB) { + cval |= UART_LCR_PARITY; + bits++; + } + if (!(cflag & PARODD)) + cval |= UART_LCR_EPAR; + if (cflag & CMSPAR) + cval |= UART_LCR_SPAR; + + /* Determine divisor based on baud rate */ + baud = tty_get_baud_rate(tty); + if (!baud) + baud = 9600; /* B0 transition handled in rs_set_termios */ + baud_base = info->baud_base; + if (baud == 38400 && (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) + quot = info->custom_divisor; + else { + if (baud == 134) + /* Special case since 134 is really 134.5 */ + quot = (2*baud_base / 269); + else if (baud) + quot = baud_base / baud; + } + /* If the quotient is zero refuse the change */ + if (!quot && old_termios) { + /* FIXME: Will need updating for new tty in the end */ + tty->termios.c_cflag &= ~CBAUD; + tty->termios.c_cflag |= (old_termios->c_cflag & CBAUD); + baud = tty_get_baud_rate(tty); + if (!baud) + baud = 9600; + if (baud == 38400 && + (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) + quot = info->custom_divisor; + else { + if (baud == 134) + /* Special case since 134 is really 134.5 */ + quot = (2*baud_base / 269); + else if (baud) + quot = baud_base / baud; + } + } + /* As a last resort, if the quotient is zero, default to 9600 bps */ + if (!quot) + quot = baud_base / 9600; + info->quot = quot; + info->timeout = (XMIT_FIFO_SIZE*HZ*bits*quot) / baud_base; + info->timeout += HZ/50; /* Add .02 seconds of slop */ + + /* CTS flow control flag and modem status interrupts */ + info->IER &= ~UART_IER_MSI; + if (port->flags & ASYNC_HARDPPS_CD) + info->IER |= UART_IER_MSI; + tty_port_set_cts_flow(port, cflag & CRTSCTS); + if (cflag & CRTSCTS) + info->IER |= UART_IER_MSI; + tty_port_set_check_carrier(port, ~cflag & CLOCAL); + if (~cflag & CLOCAL) + info->IER |= UART_IER_MSI; + /* TBD: + * Does clearing IER_MSI imply that we should disable the VBL interrupt ? + */ + + /* + * Set up parity check flag + */ + + info->read_status_mask = UART_LSR_OE | UART_LSR_DR; + if (I_INPCK(tty)) + info->read_status_mask |= UART_LSR_FE | UART_LSR_PE; + if (I_BRKINT(tty) || I_PARMRK(tty)) + info->read_status_mask |= UART_LSR_BI; + + /* + * Characters to ignore + */ + info->ignore_status_mask = 0; + if (I_IGNPAR(tty)) + info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; + if (I_IGNBRK(tty)) { + info->ignore_status_mask |= UART_LSR_BI; + /* + * If we're ignore parity and break indicators, ignore + * overruns too. (For real raw support). + */ + if (I_IGNPAR(tty)) + info->ignore_status_mask |= UART_LSR_OE; + } + /* + * !!! ignore all characters if CREAD is not set + */ + if ((cflag & CREAD) == 0) + info->ignore_status_mask |= UART_LSR_DR; + local_irq_save(flags); + + { + short serper; + + /* Set up the baud rate */ + serper = quot - 1; + + /* Enable or disable parity bit */ + + if(cval & UART_LCR_PARITY) + serper |= (SERPER_PARENB); + + amiga_custom.serper = serper; + mb(); + } + + local_irq_restore(flags); +} + +static int rs_put_char(struct tty_struct *tty, u8 ch) +{ + struct serial_state *info; + unsigned long flags; + + info = tty->driver_data; + + if (!info->xmit.buf) + return 0; + + local_irq_save(flags); + if (CIRC_SPACE(info->xmit.head, + info->xmit.tail, + UART_XMIT_SIZE) == 0) { + local_irq_restore(flags); + return 0; + } + + info->xmit.buf[info->xmit.head++] = ch; + info->xmit.head &= UART_XMIT_SIZE - 1; + local_irq_restore(flags); + return 1; +} + +static void rs_flush_chars(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; + + if (info->xmit.head == info->xmit.tail + || tty->flow.stopped + || tty->hw_stopped + || !info->xmit.buf) + return; + + local_irq_save(flags); + info->IER |= UART_IER_THRI; + amiga_custom.intena = IF_SETCLR | IF_TBE; + mb(); + /* set a pending Tx Interrupt, transmitter should restart now */ + amiga_custom.intreq = IF_SETCLR | IF_TBE; + mb(); + local_irq_restore(flags); +} + +static ssize_t rs_write(struct tty_struct * tty, const u8 *buf, size_t count) +{ + int c, ret = 0; + struct serial_state *info = tty->driver_data; + unsigned long flags; + + if (!info->xmit.buf) + return 0; + + local_irq_save(flags); + while (1) { + c = CIRC_SPACE_TO_END(info->xmit.head, + info->xmit.tail, + UART_XMIT_SIZE); + if (count < c) + c = count; + if (c <= 0) { + break; + } + memcpy(info->xmit.buf + info->xmit.head, buf, c); + info->xmit.head = (info->xmit.head + c) & (UART_XMIT_SIZE - 1); + buf += c; + count -= c; + ret += c; + } + local_irq_restore(flags); + + if (info->xmit.head != info->xmit.tail + && !tty->flow.stopped + && !tty->hw_stopped + && !(info->IER & UART_IER_THRI)) { + info->IER |= UART_IER_THRI; + local_irq_disable(); + amiga_custom.intena = IF_SETCLR | IF_TBE; + mb(); + /* set a pending Tx Interrupt, transmitter should restart now */ + amiga_custom.intreq = IF_SETCLR | IF_TBE; + mb(); + local_irq_restore(flags); + } + return ret; +} + +static unsigned int rs_write_room(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + + return CIRC_SPACE(info->xmit.head, info->xmit.tail, UART_XMIT_SIZE); +} + +static unsigned int rs_chars_in_buffer(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + + return CIRC_CNT(info->xmit.head, info->xmit.tail, UART_XMIT_SIZE); +} + +static void rs_flush_buffer(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; + + local_irq_save(flags); + info->xmit.head = info->xmit.tail = 0; + local_irq_restore(flags); + tty_wakeup(tty); +} + +/* + * This function is used to send a high-priority XON/XOFF character to + * the device + */ +static void rs_send_xchar(struct tty_struct *tty, char ch) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; + + info->x_char = ch; + if (ch) { + /* Make sure transmit interrupts are on */ + + /* Check this ! */ + local_irq_save(flags); + if(!(amiga_custom.intenar & IF_TBE)) { + amiga_custom.intena = IF_SETCLR | IF_TBE; + mb(); + /* set a pending Tx Interrupt, transmitter should restart now */ + amiga_custom.intreq = IF_SETCLR | IF_TBE; + mb(); + } + local_irq_restore(flags); + + info->IER |= UART_IER_THRI; + } +} + +/* + * ------------------------------------------------------------ + * 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 serial_state *info = tty->driver_data; + unsigned long flags; +#ifdef SERIAL_DEBUG_THROTTLE + printk("throttle %s ....\n", tty_name(tty)); +#endif + + if (I_IXOFF(tty)) + rs_send_xchar(tty, STOP_CHAR(tty)); + + if (C_CRTSCTS(tty)) + info->MCR &= ~SER_RTS; + + local_irq_save(flags); + rtsdtr_ctrl(info->MCR); + local_irq_restore(flags); +} + +static void rs_unthrottle(struct tty_struct * tty) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; +#ifdef SERIAL_DEBUG_THROTTLE + printk("unthrottle %s ....\n", tty_name(tty)); +#endif + + if (I_IXOFF(tty)) { + if (info->x_char) + info->x_char = 0; + else + rs_send_xchar(tty, START_CHAR(tty)); + } + if (C_CRTSCTS(tty)) + info->MCR |= SER_RTS; + local_irq_save(flags); + rtsdtr_ctrl(info->MCR); + local_irq_restore(flags); +} + +/* + * ------------------------------------------------------------ + * rs_ioctl() and friends + * ------------------------------------------------------------ + */ + +static int get_serial_info(struct tty_struct *tty, struct serial_struct *ss) +{ + struct serial_state *state = tty->driver_data; + unsigned int close_delay, closing_wait; + + tty_lock(tty); + close_delay = jiffies_to_msecs(state->tport.close_delay) / 10; + closing_wait = state->tport.closing_wait; + if (closing_wait != ASYNC_CLOSING_WAIT_NONE) + closing_wait = jiffies_to_msecs(closing_wait) / 10; + + ss->line = tty->index; + ss->port = state->port; + ss->flags = state->tport.flags; + ss->xmit_fifo_size = XMIT_FIFO_SIZE; + ss->baud_base = state->baud_base; + ss->close_delay = close_delay; + ss->closing_wait = closing_wait; + ss->custom_divisor = state->custom_divisor; + tty_unlock(tty); + return 0; +} + +static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss) +{ + struct serial_state *state = tty->driver_data; + struct tty_port *port = &state->tport; + bool change_spd; + int retval = 0; + unsigned int close_delay, closing_wait; + + tty_lock(tty); + change_spd = ((ss->flags ^ port->flags) & ASYNC_SPD_MASK) || + ss->custom_divisor != state->custom_divisor; + if (ss->irq || ss->port != state->port || + ss->xmit_fifo_size != XMIT_FIFO_SIZE) { + tty_unlock(tty); + return -EINVAL; + } + + close_delay = msecs_to_jiffies(ss->close_delay * 10); + closing_wait = ss->closing_wait; + if (closing_wait != ASYNC_CLOSING_WAIT_NONE) + closing_wait = msecs_to_jiffies(closing_wait * 10); + + if (!capable(CAP_SYS_ADMIN)) { + if ((ss->baud_base != state->baud_base) || + (close_delay != port->close_delay) || + (closing_wait != port->closing_wait) || + ((ss->flags & ~ASYNC_USR_MASK) != + (port->flags & ~ASYNC_USR_MASK))) { + tty_unlock(tty); + return -EPERM; + } + port->flags = ((port->flags & ~ASYNC_USR_MASK) | + (ss->flags & ASYNC_USR_MASK)); + state->custom_divisor = ss->custom_divisor; + goto check_and_exit; + } + + if (ss->baud_base < 9600) { + tty_unlock(tty); + return -EINVAL; + } + + /* + * OK, past this point, all the error checking has been done. + * At this point, we start making changes..... + */ + + state->baud_base = ss->baud_base; + port->flags = ((port->flags & ~ASYNC_FLAGS) | + (ss->flags & ASYNC_FLAGS)); + state->custom_divisor = ss->custom_divisor; + port->close_delay = close_delay; + port->closing_wait = closing_wait; + +check_and_exit: + if (tty_port_initialized(port)) { + if (change_spd) { + /* warn about deprecation unless clearing */ + if (ss->flags & ASYNC_SPD_MASK) + dev_warn_ratelimited(tty->dev, "use of SPD flags is deprecated\n"); + change_speed(tty, state, NULL); + } + } else + retval = startup(tty, state); + tty_unlock(tty); + 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 serial_state *info, unsigned int __user *value) +{ + unsigned char status; + unsigned int result; + unsigned long flags; + + local_irq_save(flags); + status = amiga_custom.serdatr; + mb(); + local_irq_restore(flags); + result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0); + if (copy_to_user(value, &result, sizeof(int))) + return -EFAULT; + return 0; +} + + +static int rs_tiocmget(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + unsigned char control, status; + unsigned long flags; + + if (tty_io_error(tty)) + return -EIO; + + control = info->MCR; + local_irq_save(flags); + status = ciab.pra; + local_irq_restore(flags); + return ((control & SER_RTS) ? TIOCM_RTS : 0) + | ((control & SER_DTR) ? TIOCM_DTR : 0) + | (!(status & SER_DCD) ? TIOCM_CAR : 0) + | (!(status & SER_DSR) ? TIOCM_DSR : 0) + | (!(status & SER_CTS) ? TIOCM_CTS : 0); +} + +static int rs_tiocmset(struct tty_struct *tty, unsigned int set, + unsigned int clear) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; + + if (tty_io_error(tty)) + return -EIO; + + local_irq_save(flags); + if (set & TIOCM_RTS) + info->MCR |= SER_RTS; + if (set & TIOCM_DTR) + info->MCR |= SER_DTR; + if (clear & TIOCM_RTS) + info->MCR &= ~SER_RTS; + if (clear & TIOCM_DTR) + info->MCR &= ~SER_DTR; + rtsdtr_ctrl(info->MCR); + local_irq_restore(flags); + return 0; +} + +/* + * rs_break() --- routine which turns the break handling on or off + */ +static int rs_break(struct tty_struct *tty, int break_state) +{ + unsigned long flags; + + local_irq_save(flags); + if (break_state == -1) + amiga_custom.adkcon = AC_SETCLR | AC_UARTBRK; + else + amiga_custom.adkcon = AC_UARTBRK; + mb(); + local_irq_restore(flags); + return 0; +} + +/* + * Get counter of input serial line interrupts (DCD,RI,DSR,CTS) + * Return: write counters to the user passed counter struct + * NB: both 1->0 and 0->1 transitions are counted except for + * RI where only 0->1 is counted. + */ +static int rs_get_icount(struct tty_struct *tty, + struct serial_icounter_struct *icount) +{ + struct serial_state *info = tty->driver_data; + struct async_icount cnow; + unsigned long flags; + + local_irq_save(flags); + cnow = info->icount; + local_irq_restore(flags); + icount->cts = cnow.cts; + icount->dsr = cnow.dsr; + icount->rng = cnow.rng; + icount->dcd = cnow.dcd; + icount->rx = cnow.rx; + icount->tx = cnow.tx; + icount->frame = cnow.frame; + icount->overrun = cnow.overrun; + icount->parity = cnow.parity; + icount->brk = cnow.brk; + icount->buf_overrun = cnow.buf_overrun; + + return 0; +} + +static int rs_ioctl(struct tty_struct *tty, + unsigned int cmd, unsigned long arg) +{ + struct serial_state *info = tty->driver_data; + struct async_icount cprev, cnow; /* kernel counter temps */ + void __user *argp = (void __user *)arg; + unsigned long flags; + DEFINE_WAIT(wait); + int ret; + + if ((cmd != TIOCSERCONFIG) && + (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) { + if (tty_io_error(tty)) + return -EIO; + } + + switch (cmd) { + case TIOCSERCONFIG: + return 0; + + case TIOCSERGETLSR: /* Get line status register */ + return get_lsr_info(info, argp); + + /* + * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change + * - mask passed in arg for lines of interest + * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking) + * Caller should use TIOCGICOUNT to see which one it was + */ + case TIOCMIWAIT: + local_irq_save(flags); + /* note the counters on entry */ + cprev = info->icount; + local_irq_restore(flags); + while (1) { + prepare_to_wait(&info->tport.delta_msr_wait, + &wait, TASK_INTERRUPTIBLE); + local_irq_save(flags); + cnow = info->icount; /* atomic copy */ + local_irq_restore(flags); + if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && + cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) { + ret = -EIO; /* no change => error */ + break; + } + if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) || + ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) || + ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) || + ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) { + ret = 0; + break; + } + schedule(); + /* see if a signal did it */ + if (signal_pending(current)) { + ret = -ERESTARTSYS; + break; + } + cprev = cnow; + } + finish_wait(&info->tport.delta_msr_wait, &wait); + return ret; + + default: + return -ENOIOCTLCMD; + } + return 0; +} + +static void rs_set_termios(struct tty_struct *tty, const struct ktermios *old_termios) +{ + struct serial_state *info = tty->driver_data; + unsigned long flags; + unsigned int cflag = tty->termios.c_cflag; + + change_speed(tty, info, old_termios); + + /* Handle transition to B0 status */ + if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD)) { + info->MCR &= ~(SER_DTR|SER_RTS); + local_irq_save(flags); + rtsdtr_ctrl(info->MCR); + local_irq_restore(flags); + } + + /* Handle transition away from B0 status */ + if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) { + info->MCR |= SER_DTR; + if (!C_CRTSCTS(tty) || !tty_throttled(tty)) + info->MCR |= SER_RTS; + local_irq_save(flags); + rtsdtr_ctrl(info->MCR); + local_irq_restore(flags); + } + + /* Handle turning off CRTSCTS */ + if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) { + tty->hw_stopped = false; + rs_start(tty); + } + +#if 0 + /* + * No need to wake up processes in open wait, since they + * sample the CLOCAL flag once, and don't recheck it. + * XXX It's not clear whether the current behavior is correct + * or not. Hence, this may change..... + */ + if (!(old_termios->c_cflag & CLOCAL) && C_CLOCAL(tty)) + wake_up_interruptible(&info->open_wait); +#endif +} + +/* + * ------------------------------------------------------------ + * 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 + * async 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 serial_state *state = tty->driver_data; + struct tty_port *port = &state->tport; + + if (tty_port_close_start(port, tty, filp) == 0) + return; + + /* + * 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. + */ + state->read_status_mask &= ~UART_LSR_DR; + if (tty_port_initialized(port)) { + /* disable receive interrupts */ + amiga_custom.intena = IF_RBF; + mb(); + /* clear any pending receive interrupt */ + amiga_custom.intreq = IF_RBF; + mb(); + + /* + * Before we drop DTR, make sure the UART transmitter + * has completely drained; this is especially + * important if there is a transmit FIFO! + */ + rs_wait_until_sent(tty, state->timeout); + } + shutdown(tty, state); + rs_flush_buffer(tty); + + tty_ldisc_flush(tty); + port->tty = NULL; + + tty_port_close_end(port, tty); +} + +/* + * rs_wait_until_sent() --- wait until the transmitter is empty + */ +static void rs_wait_until_sent(struct tty_struct *tty, int timeout) +{ + struct serial_state *info = tty->driver_data; + unsigned long orig_jiffies, char_time; + int lsr; + + orig_jiffies = jiffies; + + /* + * Set the check interval to be 1/5 of the estimated time to + * send a single character, and make it at least 1. The check + * interval should also be less than the timeout. + * + * Note: we have to use pretty tight timings here to satisfy + * the NIST-PCTS. + */ + char_time = (info->timeout - HZ/50) / XMIT_FIFO_SIZE; + char_time = char_time / 5; + if (char_time == 0) + char_time = 1; + if (timeout) + char_time = min_t(unsigned long, char_time, timeout); + /* + * If the transmitter hasn't cleared in twice the approximate + * amount of time to send the entire FIFO, it probably won't + * ever clear. This assumes the UART isn't doing flow + * control, which is currently the case. Hence, if it ever + * takes longer than info->timeout, this is probably due to a + * UART bug of some kind. So, we clamp the timeout parameter at + * 2*info->timeout. + */ + if (!timeout || timeout > 2*info->timeout) + timeout = 2*info->timeout; +#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT + printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time); + printk("jiff=%lu...", jiffies); +#endif + while(!((lsr = amiga_custom.serdatr) & SDR_TSRE)) { +#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT + printk("serdatr = %d (jiff=%lu)...", lsr, jiffies); +#endif + msleep_interruptible(jiffies_to_msecs(char_time)); + if (signal_pending(current)) + break; + if (timeout && time_after(jiffies, orig_jiffies + timeout)) + break; + } + __set_current_state(TASK_RUNNING); + +#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT + printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies); +#endif +} + +/* + * rs_hangup() --- called by tty_hangup() when a hangup is signaled. + */ +static void rs_hangup(struct tty_struct *tty) +{ + struct serial_state *info = tty->driver_data; + + rs_flush_buffer(tty); + shutdown(tty, info); + info->tport.count = 0; + tty_port_set_active(&info->tport, false); + info->tport.tty = NULL; + wake_up_interruptible(&info->tport.open_wait); +} + +/* + * This routine is called whenever a serial port is opened. It + * enables interrupts for a serial port, linking in its async structure into + * the IRQ chain. It also performs the serial-specific + * initialization for the tty structure. + */ +static int rs_open(struct tty_struct *tty, struct file * filp) +{ + struct tty_port *port = tty->port; + struct serial_state *info = container_of(port, struct serial_state, + tport); + int retval; + + port->count++; + port->tty = tty; + tty->driver_data = info; + + retval = startup(tty, info); + if (retval) { + return retval; + } + + return tty_port_block_til_ready(port, tty, filp); +} + +/* + * /proc fs routines.... + */ + +static inline void line_info(struct seq_file *m, int line, + struct serial_state *state) +{ + char stat_buf[30], control, status; + unsigned long flags; + + seq_printf(m, "%d: uart:amiga_builtin", line); + + local_irq_save(flags); + status = ciab.pra; + control = tty_port_initialized(&state->tport) ? state->MCR : status; + local_irq_restore(flags); + + stat_buf[0] = 0; + stat_buf[1] = 0; + if(!(control & SER_RTS)) + strcat(stat_buf, "|RTS"); + if(!(status & SER_CTS)) + strcat(stat_buf, "|CTS"); + if(!(control & SER_DTR)) + strcat(stat_buf, "|DTR"); + if(!(status & SER_DSR)) + strcat(stat_buf, "|DSR"); + if(!(status & SER_DCD)) + strcat(stat_buf, "|CD"); + + if (state->quot) + seq_printf(m, " baud:%d", state->baud_base / state->quot); + + seq_printf(m, " tx:%d rx:%d", state->icount.tx, state->icount.rx); + + if (state->icount.frame) + seq_printf(m, " fe:%d", state->icount.frame); + + if (state->icount.parity) + seq_printf(m, " pe:%d", state->icount.parity); + + if (state->icount.brk) + seq_printf(m, " brk:%d", state->icount.brk); + + if (state->icount.overrun) + seq_printf(m, " oe:%d", state->icount.overrun); + + /* + * Last thing is the RS-232 status lines + */ + seq_printf(m, " %s\n", stat_buf+1); +} + +static int rs_proc_show(struct seq_file *m, void *v) +{ + seq_printf(m, "serinfo:1.0 driver:4.30\n"); + line_info(m, 0, &serial_state); + return 0; +} + +/* + * --------------------------------------------------------------------- + * rs_init() and friends + * + * rs_init() is called at boot-time to initialize the serial driver. + * --------------------------------------------------------------------- + */ + +static const struct tty_operations serial_ops = { + .open = rs_open, + .close = rs_close, + .write = rs_write, + .put_char = rs_put_char, + .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, + .break_ctl = rs_break, + .send_xchar = rs_send_xchar, + .wait_until_sent = rs_wait_until_sent, + .tiocmget = rs_tiocmget, + .tiocmset = rs_tiocmset, + .get_icount = rs_get_icount, + .set_serial = set_serial_info, + .get_serial = get_serial_info, + .proc_show = rs_proc_show, +}; + +static bool amiga_carrier_raised(struct tty_port *port) +{ + return !(ciab.pra & SER_DCD); +} + +static void amiga_dtr_rts(struct tty_port *port, bool active) +{ + struct serial_state *info = container_of(port, struct serial_state, + tport); + unsigned long flags; + + if (active) + info->MCR |= SER_DTR|SER_RTS; + else + info->MCR &= ~(SER_DTR|SER_RTS); + + local_irq_save(flags); + rtsdtr_ctrl(info->MCR); + local_irq_restore(flags); +} + +static const struct tty_port_operations amiga_port_ops = { + .carrier_raised = amiga_carrier_raised, + .dtr_rts = amiga_dtr_rts, +}; + +/* + * The serial driver boot-time initialization code! + */ +static int __init amiga_serial_probe(struct platform_device *pdev) +{ + struct serial_state *state = &serial_state; + struct tty_driver *driver; + unsigned long flags; + int error; + + driver = tty_alloc_driver(1, TTY_DRIVER_REAL_RAW); + if (IS_ERR(driver)) + return PTR_ERR(driver); + + /* Initialize the tty_driver structure */ + + driver->driver_name = "amiserial"; + driver->name = "ttyS"; + driver->major = TTY_MAJOR; + driver->minor_start = 64; + driver->type = TTY_DRIVER_TYPE_SERIAL; + driver->subtype = SERIAL_TYPE_NORMAL; + driver->init_termios = tty_std_termios; + driver->init_termios.c_cflag = + B9600 | CS8 | CREAD | HUPCL | CLOCAL; + tty_set_operations(driver, &serial_ops); + + memset(state, 0, sizeof(*state)); + state->port = (int)&amiga_custom.serdatr; /* Just to give it a value */ + tty_port_init(&state->tport); + state->tport.ops = &amiga_port_ops; + tty_port_link_device(&state->tport, driver, 0); + + error = tty_register_driver(driver); + if (error) + goto fail_tty_driver_kref_put; + + printk(KERN_INFO "ttyS0 is the amiga builtin serial port\n"); + + /* Hardware set up */ + + state->baud_base = amiga_colorclock; + + /* set ISRs, and then disable the rx interrupts */ + error = request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state); + if (error) + goto fail_unregister; + + error = request_irq(IRQ_AMIGA_RBF, ser_rx_int, 0, + "serial RX", state); + if (error) + goto fail_free_irq; + + local_irq_save(flags); + + /* turn off Rx and Tx interrupts */ + amiga_custom.intena = IF_RBF | IF_TBE; + mb(); + + /* clear any pending interrupt */ + amiga_custom.intreq = IF_RBF | IF_TBE; + mb(); + + local_irq_restore(flags); + + /* + * set the appropriate directions for the modem control flags, + * and clear RTS and DTR + */ + ciab.ddra |= (SER_DTR | SER_RTS); /* outputs */ + ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR); /* inputs */ + + platform_set_drvdata(pdev, state); + + serial_driver = driver; + + return 0; + +fail_free_irq: + free_irq(IRQ_AMIGA_TBE, state); +fail_unregister: + tty_unregister_driver(driver); +fail_tty_driver_kref_put: + tty_port_destroy(&state->tport); + tty_driver_kref_put(driver); + return error; +} + +static int __exit amiga_serial_remove(struct platform_device *pdev) +{ + struct serial_state *state = platform_get_drvdata(pdev); + + tty_unregister_driver(serial_driver); + tty_driver_kref_put(serial_driver); + tty_port_destroy(&state->tport); + + free_irq(IRQ_AMIGA_TBE, state); + free_irq(IRQ_AMIGA_RBF, state); + + return 0; +} + +static struct platform_driver amiga_serial_driver = { + .remove = __exit_p(amiga_serial_remove), + .driver = { + .name = "amiga-serial", + }, +}; + +module_platform_driver_probe(amiga_serial_driver, amiga_serial_probe); + + +#if defined(CONFIG_SERIAL_CONSOLE) && !defined(MODULE) + +/* + * ------------------------------------------------------------ + * Serial console driver + * ------------------------------------------------------------ + */ + +static void amiga_serial_putc(char c) +{ + amiga_custom.serdat = (unsigned char)c | 0x100; + while (!(amiga_custom.serdatr & 0x2000)) + barrier(); +} + +/* + * Print a string to the serial port trying not to disturb + * any possible real use of the port... + * + * The console must be locked when we get here. + */ +static void serial_console_write(struct console *co, const char *s, + unsigned count) +{ + unsigned short intena = amiga_custom.intenar; + + amiga_custom.intena = IF_TBE; + + while (count--) { + if (*s == '\n') + amiga_serial_putc('\r'); + amiga_serial_putc(*s++); + } + + amiga_custom.intena = IF_SETCLR | (intena & IF_TBE); +} + +static struct tty_driver *serial_console_device(struct console *c, int *index) +{ + *index = 0; + return serial_driver; +} + +static struct console sercons = { + .name = "ttyS", + .write = serial_console_write, + .device = serial_console_device, + .flags = CON_PRINTBUFFER, + .index = -1, +}; + +/* + * Register console. + */ +static int __init amiserial_console_init(void) +{ + if (!MACH_IS_AMIGA) + return -ENODEV; + + register_console(&sercons); + return 0; +} +console_initcall(amiserial_console_init); + +#endif /* CONFIG_SERIAL_CONSOLE && !MODULE */ + +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:amiga-serial"); |