diff options
author | Greg Kroah-Hartman <gregkh@suse.de> | 2011-01-13 20:10:18 (GMT) |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-01-13 20:10:18 (GMT) |
commit | ab4382d27412e7e3e7c936e8d50d8888dfac3df8 (patch) | |
tree | 51d96dea2431140358784b6b426715f37f74fd53 /drivers/tty/serial/dz.c | |
parent | 728674a7e466628df2aeec6d11a2ae1ef968fb67 (diff) | |
download | linux-fsl-qoriq-ab4382d27412e7e3e7c936e8d50d8888dfac3df8.tar.xz |
tty: move drivers/serial/ to drivers/tty/serial/
The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.
This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/tty/serial/dz.c')
-rw-r--r-- | drivers/tty/serial/dz.c | 955 |
1 files changed, 955 insertions, 0 deletions
diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c new file mode 100644 index 0000000..57421d7 --- /dev/null +++ b/drivers/tty/serial/dz.c @@ -0,0 +1,955 @@ +/* + * dz.c: Serial port driver for DECstations equipped + * with the DZ chipset. + * + * Copyright (C) 1998 Olivier A. D. Lebaillif + * + * Email: olivier.lebaillif@ifrsys.com + * + * Copyright (C) 2004, 2006, 2007 Maciej W. Rozycki + * + * [31-AUG-98] triemer + * Changed IRQ to use Harald's dec internals interrupts.h + * removed base_addr code - moving address assignment to setup.c + * Changed name of dz_init to rs_init to be consistent with tc code + * [13-NOV-98] triemer fixed code to receive characters + * after patches by harald to irq code. + * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout + * field from "current" - somewhere between 2.1.121 and 2.1.131 + Qua Jun 27 15:02:26 BRT 2001 + * [27-JUN-2001] Arnaldo Carvalho de Melo <acme@conectiva.com.br> - cleanups + * + * Parts (C) 1999 David Airlie, airlied@linux.ie + * [07-SEP-99] Bugfixes + * + * [06-Jan-2002] Russell King <rmk@arm.linux.org.uk> + * Converted to new serial core + */ + +#undef DEBUG_DZ + +#if defined(CONFIG_SERIAL_DZ_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + +#include <linux/bitops.h> +#include <linux/compiler.h> +#include <linux/console.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/major.h> +#include <linux/module.h> +#include <linux/serial.h> +#include <linux/serial_core.h> +#include <linux/sysrq.h> +#include <linux/tty.h> + +#include <asm/atomic.h> +#include <asm/bootinfo.h> +#include <asm/io.h> +#include <asm/system.h> + +#include <asm/dec/interrupts.h> +#include <asm/dec/kn01.h> +#include <asm/dec/kn02.h> +#include <asm/dec/machtype.h> +#include <asm/dec/prom.h> +#include <asm/dec/system.h> + +#include "dz.h" + + +MODULE_DESCRIPTION("DECstation DZ serial driver"); +MODULE_LICENSE("GPL"); + + +static char dz_name[] __initdata = "DECstation DZ serial driver version "; +static char dz_version[] __initdata = "1.04"; + +struct dz_port { + struct dz_mux *mux; + struct uart_port port; + unsigned int cflag; +}; + +struct dz_mux { + struct dz_port dport[DZ_NB_PORT]; + atomic_t map_guard; + atomic_t irq_guard; + int initialised; +}; + +static struct dz_mux dz_mux; + +static inline struct dz_port *to_dport(struct uart_port *uport) +{ + return container_of(uport, struct dz_port, port); +} + +/* + * ------------------------------------------------------------ + * dz_in () and dz_out () + * + * These routines are used to access the registers of the DZ + * chip, hiding relocation differences between implementation. + * ------------------------------------------------------------ + */ + +static u16 dz_in(struct dz_port *dport, unsigned offset) +{ + void __iomem *addr = dport->port.membase + offset; + + return readw(addr); +} + +static void dz_out(struct dz_port *dport, unsigned offset, u16 value) +{ + void __iomem *addr = dport->port.membase + offset; + + writew(value, addr); +} + +/* + * ------------------------------------------------------------ + * rs_stop () and rs_start () + * + * These routines are called before setting or resetting + * tty->stopped. They enable or disable transmitter interrupts, + * as necessary. + * ------------------------------------------------------------ + */ + +static void dz_stop_tx(struct uart_port *uport) +{ + struct dz_port *dport = to_dport(uport); + u16 tmp, mask = 1 << dport->port.line; + + tmp = dz_in(dport, DZ_TCR); /* read the TX flag */ + tmp &= ~mask; /* clear the TX flag */ + dz_out(dport, DZ_TCR, tmp); +} + +static void dz_start_tx(struct uart_port *uport) +{ + struct dz_port *dport = to_dport(uport); + u16 tmp, mask = 1 << dport->port.line; + + tmp = dz_in(dport, DZ_TCR); /* read the TX flag */ + tmp |= mask; /* set the TX flag */ + dz_out(dport, DZ_TCR, tmp); +} + +static void dz_stop_rx(struct uart_port *uport) +{ + struct dz_port *dport = to_dport(uport); + + dport->cflag &= ~DZ_RXENAB; + dz_out(dport, DZ_LPR, dport->cflag); +} + +static void dz_enable_ms(struct uart_port *uport) +{ + /* nothing to do */ +} + +/* + * ------------------------------------------------------------ + * + * Here start the interrupt handling routines. All of the following + * subroutines are declared as inline and are folded into + * dz_interrupt. They were separated out for readability's sake. + * + * Note: dz_interrupt() is a "fast" interrupt, which means that it + * runs with interrupts turned off. People who may want to modify + * dz_interrupt() should try to keep the interrupt handler as fast as + * possible. After you are done making modifications, it is not a bad + * idea to do: + * + * make drivers/serial/dz.s + * + * and look at the resulting assemble code in dz.s. + * + * ------------------------------------------------------------ + */ + +/* + * ------------------------------------------------------------ + * receive_char () + * + * This routine deals with inputs from any lines. + * ------------------------------------------------------------ + */ +static inline void dz_receive_chars(struct dz_mux *mux) +{ + struct uart_port *uport; + struct dz_port *dport = &mux->dport[0]; + struct tty_struct *tty = NULL; + struct uart_icount *icount; + int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 }; + unsigned char ch, flag; + u16 status; + int i; + + while ((status = dz_in(dport, DZ_RBUF)) & DZ_DVAL) { + dport = &mux->dport[LINE(status)]; + uport = &dport->port; + tty = uport->state->port.tty; /* point to the proper dev */ + + ch = UCHAR(status); /* grab the char */ + flag = TTY_NORMAL; + + icount = &uport->icount; + icount->rx++; + + if (unlikely(status & (DZ_OERR | DZ_FERR | DZ_PERR))) { + + /* + * There is no separate BREAK status bit, so treat + * null characters with framing errors as BREAKs; + * normally, otherwise. For this move the Framing + * Error bit to a simulated BREAK bit. + */ + if (!ch) { + status |= (status & DZ_FERR) >> + (ffs(DZ_FERR) - ffs(DZ_BREAK)); + status &= ~DZ_FERR; + } + + /* Handle SysRq/SAK & keep track of the statistics. */ + if (status & DZ_BREAK) { + icount->brk++; + if (uart_handle_break(uport)) + continue; + } else if (status & DZ_FERR) + icount->frame++; + else if (status & DZ_PERR) + icount->parity++; + if (status & DZ_OERR) + icount->overrun++; + + status &= uport->read_status_mask; + if (status & DZ_BREAK) + flag = TTY_BREAK; + else if (status & DZ_FERR) + flag = TTY_FRAME; + else if (status & DZ_PERR) + flag = TTY_PARITY; + + } + + if (uart_handle_sysrq_char(uport, ch)) + continue; + + uart_insert_char(uport, status, DZ_OERR, ch, flag); + lines_rx[LINE(status)] = 1; + } + for (i = 0; i < DZ_NB_PORT; i++) + if (lines_rx[i]) + tty_flip_buffer_push(mux->dport[i].port.state->port.tty); +} + +/* + * ------------------------------------------------------------ + * transmit_char () + * + * This routine deals with outputs to any lines. + * ------------------------------------------------------------ + */ +static inline void dz_transmit_chars(struct dz_mux *mux) +{ + struct dz_port *dport = &mux->dport[0]; + struct circ_buf *xmit; + unsigned char tmp; + u16 status; + + status = dz_in(dport, DZ_CSR); + dport = &mux->dport[LINE(status)]; + xmit = &dport->port.state->xmit; + + if (dport->port.x_char) { /* XON/XOFF chars */ + dz_out(dport, DZ_TDR, dport->port.x_char); + dport->port.icount.tx++; + dport->port.x_char = 0; + return; + } + /* If nothing to do or stopped or hardware stopped. */ + if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) { + spin_lock(&dport->port.lock); + dz_stop_tx(&dport->port); + spin_unlock(&dport->port.lock); + return; + } + + /* + * If something to do... (remember the dz has no output fifo, + * so we go one char at a time) :-< + */ + tmp = xmit->buf[xmit->tail]; + xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1); + dz_out(dport, DZ_TDR, tmp); + dport->port.icount.tx++; + + if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS) + uart_write_wakeup(&dport->port); + + /* Are we are done. */ + if (uart_circ_empty(xmit)) { + spin_lock(&dport->port.lock); + dz_stop_tx(&dport->port); + spin_unlock(&dport->port.lock); + } +} + +/* + * ------------------------------------------------------------ + * check_modem_status() + * + * DS 3100 & 5100: Only valid for the MODEM line, duh! + * DS 5000/200: Valid for the MODEM and PRINTER line. + * ------------------------------------------------------------ + */ +static inline void check_modem_status(struct dz_port *dport) +{ + /* + * FIXME: + * 1. No status change interrupt; use a timer. + * 2. Handle the 3100/5000 as appropriate. --macro + */ + u16 status; + + /* If not the modem line just return. */ + if (dport->port.line != DZ_MODEM) + return; + + status = dz_in(dport, DZ_MSR); + + /* it's easy, since DSR2 is the only bit in the register */ + if (status) + dport->port.icount.dsr++; +} + +/* + * ------------------------------------------------------------ + * dz_interrupt () + * + * this is the main interrupt routine for the DZ chip. + * It deals with the multiple ports. + * ------------------------------------------------------------ + */ +static irqreturn_t dz_interrupt(int irq, void *dev_id) +{ + struct dz_mux *mux = dev_id; + struct dz_port *dport = &mux->dport[0]; + u16 status; + + /* get the reason why we just got an irq */ + status = dz_in(dport, DZ_CSR); + + if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE)) + dz_receive_chars(mux); + + if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE)) + dz_transmit_chars(mux); + + return IRQ_HANDLED; +} + +/* + * ------------------------------------------------------------------- + * Here ends the DZ interrupt routines. + * ------------------------------------------------------------------- + */ + +static unsigned int dz_get_mctrl(struct uart_port *uport) +{ + /* + * FIXME: Handle the 3100/5000 as appropriate. --macro + */ + struct dz_port *dport = to_dport(uport); + unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + + if (dport->port.line == DZ_MODEM) { + if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR) + mctrl &= ~TIOCM_DSR; + } + + return mctrl; +} + +static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl) +{ + /* + * FIXME: Handle the 3100/5000 as appropriate. --macro + */ + struct dz_port *dport = to_dport(uport); + u16 tmp; + + if (dport->port.line == DZ_MODEM) { + tmp = dz_in(dport, DZ_TCR); + if (mctrl & TIOCM_DTR) + tmp &= ~DZ_MODEM_DTR; + else + tmp |= DZ_MODEM_DTR; + dz_out(dport, DZ_TCR, tmp); + } +} + +/* + * ------------------------------------------------------------------- + * startup () + * + * various initialization tasks + * ------------------------------------------------------------------- + */ +static int dz_startup(struct uart_port *uport) +{ + struct dz_port *dport = to_dport(uport); + struct dz_mux *mux = dport->mux; + unsigned long flags; + int irq_guard; + int ret; + u16 tmp; + + irq_guard = atomic_add_return(1, &mux->irq_guard); + if (irq_guard != 1) + return 0; + + ret = request_irq(dport->port.irq, dz_interrupt, + IRQF_SHARED, "dz", mux); + if (ret) { + atomic_add(-1, &mux->irq_guard); + printk(KERN_ERR "dz: Cannot get IRQ %d!\n", dport->port.irq); + return ret; + } + + spin_lock_irqsave(&dport->port.lock, flags); + + /* Enable interrupts. */ + tmp = dz_in(dport, DZ_CSR); + tmp |= DZ_RIE | DZ_TIE; + dz_out(dport, DZ_CSR, tmp); + + spin_unlock_irqrestore(&dport->port.lock, flags); + + return 0; +} + +/* + * ------------------------------------------------------------------- + * shutdown () + * + * 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 dz_shutdown(struct uart_port *uport) +{ + struct dz_port *dport = to_dport(uport); + struct dz_mux *mux = dport->mux; + unsigned long flags; + int irq_guard; + u16 tmp; + + spin_lock_irqsave(&dport->port.lock, flags); + dz_stop_tx(&dport->port); + spin_unlock_irqrestore(&dport->port.lock, flags); + + irq_guard = atomic_add_return(-1, &mux->irq_guard); + if (!irq_guard) { + /* Disable interrupts. */ + tmp = dz_in(dport, DZ_CSR); + tmp &= ~(DZ_RIE | DZ_TIE); + dz_out(dport, DZ_CSR, tmp); + + free_irq(dport->port.irq, mux); + } +} + +/* + * ------------------------------------------------------------------- + * dz_tx_empty() -- get the transmitter empty status + * + * 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 unsigned int dz_tx_empty(struct uart_port *uport) +{ + struct dz_port *dport = to_dport(uport); + unsigned short tmp, mask = 1 << dport->port.line; + + tmp = dz_in(dport, DZ_TCR); + tmp &= mask; + + return tmp ? 0 : TIOCSER_TEMT; +} + +static void dz_break_ctl(struct uart_port *uport, int break_state) +{ + /* + * FIXME: Can't access BREAK bits in TDR easily; + * reuse the code for polled TX. --macro + */ + struct dz_port *dport = to_dport(uport); + unsigned long flags; + unsigned short tmp, mask = 1 << dport->port.line; + + spin_lock_irqsave(&uport->lock, flags); + tmp = dz_in(dport, DZ_TCR); + if (break_state) + tmp |= mask; + else + tmp &= ~mask; + dz_out(dport, DZ_TCR, tmp); + spin_unlock_irqrestore(&uport->lock, flags); +} + +static int dz_encode_baud_rate(unsigned int baud) +{ + switch (baud) { + case 50: + return DZ_B50; + case 75: + return DZ_B75; + case 110: + return DZ_B110; + case 134: + return DZ_B134; + case 150: + return DZ_B150; + case 300: + return DZ_B300; + case 600: + return DZ_B600; + case 1200: + return DZ_B1200; + case 1800: + return DZ_B1800; + case 2000: + return DZ_B2000; + case 2400: + return DZ_B2400; + case 3600: + return DZ_B3600; + case 4800: + return DZ_B4800; + case 7200: + return DZ_B7200; + case 9600: + return DZ_B9600; + default: + return -1; + } +} + + +static void dz_reset(struct dz_port *dport) +{ + struct dz_mux *mux = dport->mux; + + if (mux->initialised) + return; + + dz_out(dport, DZ_CSR, DZ_CLR); + while (dz_in(dport, DZ_CSR) & DZ_CLR); + iob(); + + /* Enable scanning. */ + dz_out(dport, DZ_CSR, DZ_MSE); + + mux->initialised = 1; +} + +static void dz_set_termios(struct uart_port *uport, struct ktermios *termios, + struct ktermios *old_termios) +{ + struct dz_port *dport = to_dport(uport); + unsigned long flags; + unsigned int cflag, baud; + int bflag; + + cflag = dport->port.line; + + switch (termios->c_cflag & CSIZE) { + case CS5: + cflag |= DZ_CS5; + break; + case CS6: + cflag |= DZ_CS6; + break; + case CS7: + cflag |= DZ_CS7; + break; + case CS8: + default: + cflag |= DZ_CS8; + } + + if (termios->c_cflag & CSTOPB) + cflag |= DZ_CSTOPB; + if (termios->c_cflag & PARENB) + cflag |= DZ_PARENB; + if (termios->c_cflag & PARODD) + cflag |= DZ_PARODD; + + baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600); + bflag = dz_encode_baud_rate(baud); + if (bflag < 0) { /* Try to keep unchanged. */ + baud = uart_get_baud_rate(uport, old_termios, NULL, 50, 9600); + bflag = dz_encode_baud_rate(baud); + if (bflag < 0) { /* Resort to 9600. */ + baud = 9600; + bflag = DZ_B9600; + } + tty_termios_encode_baud_rate(termios, baud, baud); + } + cflag |= bflag; + + if (termios->c_cflag & CREAD) + cflag |= DZ_RXENAB; + + spin_lock_irqsave(&dport->port.lock, flags); + + uart_update_timeout(uport, termios->c_cflag, baud); + + dz_out(dport, DZ_LPR, cflag); + dport->cflag = cflag; + + /* setup accept flag */ + dport->port.read_status_mask = DZ_OERR; + if (termios->c_iflag & INPCK) + dport->port.read_status_mask |= DZ_FERR | DZ_PERR; + if (termios->c_iflag & (BRKINT | PARMRK)) + dport->port.read_status_mask |= DZ_BREAK; + + /* characters to ignore */ + uport->ignore_status_mask = 0; + if ((termios->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK)) + dport->port.ignore_status_mask |= DZ_OERR; + if (termios->c_iflag & IGNPAR) + dport->port.ignore_status_mask |= DZ_FERR | DZ_PERR; + if (termios->c_iflag & IGNBRK) + dport->port.ignore_status_mask |= DZ_BREAK; + + spin_unlock_irqrestore(&dport->port.lock, flags); +} + +/* + * Hack alert! + * Required solely so that the initial PROM-based console + * works undisturbed in parallel with this one. + */ +static void dz_pm(struct uart_port *uport, unsigned int state, + unsigned int oldstate) +{ + struct dz_port *dport = to_dport(uport); + unsigned long flags; + + spin_lock_irqsave(&dport->port.lock, flags); + if (state < 3) + dz_start_tx(&dport->port); + else + dz_stop_tx(&dport->port); + spin_unlock_irqrestore(&dport->port.lock, flags); +} + + +static const char *dz_type(struct uart_port *uport) +{ + return "DZ"; +} + +static void dz_release_port(struct uart_port *uport) +{ + struct dz_mux *mux = to_dport(uport)->mux; + int map_guard; + + iounmap(uport->membase); + uport->membase = NULL; + + map_guard = atomic_add_return(-1, &mux->map_guard); + if (!map_guard) + release_mem_region(uport->mapbase, dec_kn_slot_size); +} + +static int dz_map_port(struct uart_port *uport) +{ + if (!uport->membase) + uport->membase = ioremap_nocache(uport->mapbase, + dec_kn_slot_size); + if (!uport->membase) { + printk(KERN_ERR "dz: Cannot map MMIO\n"); + return -ENOMEM; + } + return 0; +} + +static int dz_request_port(struct uart_port *uport) +{ + struct dz_mux *mux = to_dport(uport)->mux; + int map_guard; + int ret; + + map_guard = atomic_add_return(1, &mux->map_guard); + if (map_guard == 1) { + if (!request_mem_region(uport->mapbase, dec_kn_slot_size, + "dz")) { + atomic_add(-1, &mux->map_guard); + printk(KERN_ERR + "dz: Unable to reserve MMIO resource\n"); + return -EBUSY; + } + } + ret = dz_map_port(uport); + if (ret) { + map_guard = atomic_add_return(-1, &mux->map_guard); + if (!map_guard) + release_mem_region(uport->mapbase, dec_kn_slot_size); + return ret; + } + return 0; +} + +static void dz_config_port(struct uart_port *uport, int flags) +{ + struct dz_port *dport = to_dport(uport); + + if (flags & UART_CONFIG_TYPE) { + if (dz_request_port(uport)) + return; + + uport->type = PORT_DZ; + + dz_reset(dport); + } +} + +/* + * Verify the new serial_struct (for TIOCSSERIAL). + */ +static int dz_verify_port(struct uart_port *uport, struct serial_struct *ser) +{ + int ret = 0; + + if (ser->type != PORT_UNKNOWN && ser->type != PORT_DZ) + ret = -EINVAL; + if (ser->irq != uport->irq) + ret = -EINVAL; + return ret; +} + +static struct uart_ops dz_ops = { + .tx_empty = dz_tx_empty, + .get_mctrl = dz_get_mctrl, + .set_mctrl = dz_set_mctrl, + .stop_tx = dz_stop_tx, + .start_tx = dz_start_tx, + .stop_rx = dz_stop_rx, + .enable_ms = dz_enable_ms, + .break_ctl = dz_break_ctl, + .startup = dz_startup, + .shutdown = dz_shutdown, + .set_termios = dz_set_termios, + .pm = dz_pm, + .type = dz_type, + .release_port = dz_release_port, + .request_port = dz_request_port, + .config_port = dz_config_port, + .verify_port = dz_verify_port, +}; + +static void __init dz_init_ports(void) +{ + static int first = 1; + unsigned long base; + int line; + + if (!first) + return; + first = 0; + + if (mips_machtype == MACH_DS23100 || mips_machtype == MACH_DS5100) + base = dec_kn_slot_base + KN01_DZ11; + else + base = dec_kn_slot_base + KN02_DZ11; + + for (line = 0; line < DZ_NB_PORT; line++) { + struct dz_port *dport = &dz_mux.dport[line]; + struct uart_port *uport = &dport->port; + + dport->mux = &dz_mux; + + uport->irq = dec_interrupt[DEC_IRQ_DZ11]; + uport->fifosize = 1; + uport->iotype = UPIO_MEM; + uport->flags = UPF_BOOT_AUTOCONF; + uport->ops = &dz_ops; + uport->line = line; + uport->mapbase = base; + } +} + +#ifdef CONFIG_SERIAL_DZ_CONSOLE +/* + * ------------------------------------------------------------------- + * dz_console_putchar() -- transmit a character + * + * Polled transmission. This is tricky. We need to mask transmit + * interrupts so that they do not interfere, enable the transmitter + * for the line requested and then wait till the transmit scanner + * requests data for this line. But it may request data for another + * line first, in which case we have to disable its transmitter and + * repeat waiting till our line pops up. Only then the character may + * be transmitted. Finally, the state of the transmitter mask is + * restored. Welcome to the world of PDP-11! + * ------------------------------------------------------------------- + */ +static void dz_console_putchar(struct uart_port *uport, int ch) +{ + struct dz_port *dport = to_dport(uport); + unsigned long flags; + unsigned short csr, tcr, trdy, mask; + int loops = 10000; + + spin_lock_irqsave(&dport->port.lock, flags); + csr = dz_in(dport, DZ_CSR); + dz_out(dport, DZ_CSR, csr & ~DZ_TIE); + tcr = dz_in(dport, DZ_TCR); + tcr |= 1 << dport->port.line; + mask = tcr; + dz_out(dport, DZ_TCR, mask); + iob(); + spin_unlock_irqrestore(&dport->port.lock, flags); + + do { + trdy = dz_in(dport, DZ_CSR); + if (!(trdy & DZ_TRDY)) + continue; + trdy = (trdy & DZ_TLINE) >> 8; + if (trdy == dport->port.line) + break; + mask &= ~(1 << trdy); + dz_out(dport, DZ_TCR, mask); + iob(); + udelay(2); + } while (--loops); + + if (loops) /* Cannot send otherwise. */ + dz_out(dport, DZ_TDR, ch); + + dz_out(dport, DZ_TCR, tcr); + dz_out(dport, DZ_CSR, csr); +} + +/* + * ------------------------------------------------------------------- + * dz_console_print () + * + * dz_console_print is registered for printk. + * The console must be locked when we get here. + * ------------------------------------------------------------------- + */ +static void dz_console_print(struct console *co, + const char *str, + unsigned int count) +{ + struct dz_port *dport = &dz_mux.dport[co->index]; +#ifdef DEBUG_DZ + prom_printf((char *) str); +#endif + uart_console_write(&dport->port, str, count, dz_console_putchar); +} + +static int __init dz_console_setup(struct console *co, char *options) +{ + struct dz_port *dport = &dz_mux.dport[co->index]; + struct uart_port *uport = &dport->port; + int baud = 9600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + int ret; + + ret = dz_map_port(uport); + if (ret) + return ret; + + spin_lock_init(&dport->port.lock); /* For dz_pm(). */ + + dz_reset(dport); + dz_pm(uport, 0, -1); + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(&dport->port, co, baud, parity, bits, flow); +} + +static struct uart_driver dz_reg; +static struct console dz_console = { + .name = "ttyS", + .write = dz_console_print, + .device = uart_console_device, + .setup = dz_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &dz_reg, +}; + +static int __init dz_serial_console_init(void) +{ + if (!IOASIC) { + dz_init_ports(); + register_console(&dz_console); + return 0; + } else + return -ENXIO; +} + +console_initcall(dz_serial_console_init); + +#define SERIAL_DZ_CONSOLE &dz_console +#else +#define SERIAL_DZ_CONSOLE NULL +#endif /* CONFIG_SERIAL_DZ_CONSOLE */ + +static struct uart_driver dz_reg = { + .owner = THIS_MODULE, + .driver_name = "serial", + .dev_name = "ttyS", + .major = TTY_MAJOR, + .minor = 64, + .nr = DZ_NB_PORT, + .cons = SERIAL_DZ_CONSOLE, +}; + +static int __init dz_init(void) +{ + int ret, i; + + if (IOASIC) + return -ENXIO; + + printk("%s%s\n", dz_name, dz_version); + + dz_init_ports(); + + ret = uart_register_driver(&dz_reg); + if (ret) + return ret; + + for (i = 0; i < DZ_NB_PORT; i++) + uart_add_one_port(&dz_reg, &dz_mux.dport[i].port); + + return 0; +} + +module_init(dz_init); |