- 根目录:
- drivers
- staging
- dgnc
- dgnc_cls.c
/*
* Copyright 2003 Digi International (www.digi.com)
* Scott H Kilau <Scott_Kilau at digi dot com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/sched.h> /* For jiffies, task states */
#include <linux/interrupt.h> /* For tasklet and interrupt structs/defines */
#include <linux/delay.h> /* For udelay */
#include <linux/io.h> /* For read[bwl]/write[bwl] */
#include <linux/serial.h> /* For struct async_serial */
#include <linux/serial_reg.h> /* For the various UART offsets */
#include <linux/pci.h>
#include "dgnc_driver.h" /* Driver main header file */
#include "dgnc_cls.h"
#include "dgnc_tty.h"
static inline void cls_parse_isr(struct dgnc_board *brd, uint port);
static inline void cls_clear_break(struct channel_t *ch, int force);
static inline void cls_set_cts_flow_control(struct channel_t *ch);
static inline void cls_set_rts_flow_control(struct channel_t *ch);
static inline void cls_set_ixon_flow_control(struct channel_t *ch);
static inline void cls_set_ixoff_flow_control(struct channel_t *ch);
static inline void cls_set_no_output_flow_control(struct channel_t *ch);
static inline void cls_set_no_input_flow_control(struct channel_t *ch);
static void cls_parse_modem(struct channel_t *ch, unsigned char signals);
static void cls_tasklet(unsigned long data);
static void cls_vpd(struct dgnc_board *brd);
static void cls_uart_init(struct channel_t *ch);
static void cls_uart_off(struct channel_t *ch);
static int cls_drain(struct tty_struct *tty, uint seconds);
static void cls_param(struct tty_struct *tty);
static void cls_assert_modem_signals(struct channel_t *ch);
static void cls_flush_uart_write(struct channel_t *ch);
static void cls_flush_uart_read(struct channel_t *ch);
static void cls_disable_receiver(struct channel_t *ch);
static void cls_enable_receiver(struct channel_t *ch);
static void cls_send_break(struct channel_t *ch, int msecs);
static void cls_send_start_character(struct channel_t *ch);
static void cls_send_stop_character(struct channel_t *ch);
static void cls_copy_data_from_uart_to_queue(struct channel_t *ch);
static void cls_copy_data_from_queue_to_uart(struct channel_t *ch);
static uint cls_get_uart_bytes_left(struct channel_t *ch);
static void cls_send_immediate_char(struct channel_t *ch, unsigned char);
static irqreturn_t cls_intr(int irq, void *voidbrd);
struct board_ops dgnc_cls_ops = {
.tasklet = cls_tasklet,
.intr = cls_intr,
.uart_init = cls_uart_init,
.uart_off = cls_uart_off,
.drain = cls_drain,
.param = cls_param,
.vpd = cls_vpd,
.assert_modem_signals = cls_assert_modem_signals,
.flush_uart_write = cls_flush_uart_write,
.flush_uart_read = cls_flush_uart_read,
.disable_receiver = cls_disable_receiver,
.enable_receiver = cls_enable_receiver,
.send_break = cls_send_break,
.send_start_character = cls_send_start_character,
.send_stop_character = cls_send_stop_character,
.copy_data_from_queue_to_uart = cls_copy_data_from_queue_to_uart,
.get_uart_bytes_left = cls_get_uart_bytes_left,
.send_immediate_char = cls_send_immediate_char
};
static inline void cls_set_cts_flow_control(struct channel_t *ch)
{
unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
unsigned char ier = readb(&ch->ch_cls_uart->ier);
unsigned char isr_fcr = 0;
/*
* The Enhanced Register Set may only be accessed when
* the Line Control Register is set to 0xBFh.
*/
writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
/* Turn on CTS flow control, turn off IXON flow control */
isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_CTSDSR);
isr_fcr &= ~(UART_EXAR654_EFR_IXON);
writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
/* Write old LCR value back out, which turns enhanced access off */
writeb(lcrb, &ch->ch_cls_uart->lcr);
/*
* Enable interrupts for CTS flow, turn off interrupts for
* received XOFF chars
*/
ier |= (UART_EXAR654_IER_CTSDSR);
ier &= ~(UART_EXAR654_IER_XOFF);
writeb(ier, &ch->ch_cls_uart->ier);
/* Set the usual FIFO values */
writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_56 |
UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
&ch->ch_cls_uart->isr_fcr);
ch->ch_t_tlevel = 16;
}
static inline void cls_set_ixon_flow_control(struct channel_t *ch)
{
unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
unsigned char ier = readb(&ch->ch_cls_uart->ier);
unsigned char isr_fcr = 0;
/*
* The Enhanced Register Set may only be accessed when
* the Line Control Register is set to 0xBFh.
*/
writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
/* Turn on IXON flow control, turn off CTS flow control */
isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_IXON);
isr_fcr &= ~(UART_EXAR654_EFR_CTSDSR);
writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
/* Now set our current start/stop chars while in enhanced mode */
writeb(ch->ch_startc, &ch->ch_cls_uart->mcr);
writeb(0, &ch->ch_cls_uart->lsr);
writeb(ch->ch_stopc, &ch->ch_cls_uart->msr);
writeb(0, &ch->ch_cls_uart->spr);
/* Write old LCR value back out, which turns enhanced access off */
writeb(lcrb, &ch->ch_cls_uart->lcr);
/*
* Disable interrupts for CTS flow, turn on interrupts for
* received XOFF chars
*/
ier &= ~(UART_EXAR654_IER_CTSDSR);
ier |= (UART_EXAR654_IER_XOFF);
writeb(ier, &ch->ch_cls_uart->ier);
/* Set the usual FIFO values */
writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
&ch->ch_cls_uart->isr_fcr);
}
static inline void cls_set_no_output_flow_control(struct channel_t *ch)
{
unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
unsigned char ier = readb(&ch->ch_cls_uart->ier);
unsigned char isr_fcr = 0;
/*
* The Enhanced Register Set may only be accessed when
* the Line Control Register is set to 0xBFh.
*/
writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
/* Turn off IXON flow control, turn off CTS flow control */
isr_fcr |= (UART_EXAR654_EFR_ECB);
isr_fcr &= ~(UART_EXAR654_EFR_CTSDSR | UART_EXAR654_EFR_IXON);
writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
/* Write old LCR value back out, which turns enhanced access off */
writeb(lcrb, &ch->ch_cls_uart->lcr);
/*
* Disable interrupts for CTS flow, turn off interrupts for
* received XOFF chars
*/
ier &= ~(UART_EXAR654_IER_CTSDSR);
ier &= ~(UART_EXAR654_IER_XOFF);
writeb(ier, &ch->ch_cls_uart->ier);
/* Set the usual FIFO values */
writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
&ch->ch_cls_uart->isr_fcr);
ch->ch_r_watermark = 0;
ch->ch_t_tlevel = 16;
ch->ch_r_tlevel = 16;
}
static inline void cls_set_rts_flow_control(struct channel_t *ch)
{
unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
unsigned char ier = readb(&ch->ch_cls_uart->ier);
unsigned char isr_fcr = 0;
/*
* The Enhanced Register Set may only be accessed when
* the Line Control Register is set to 0xBFh.
*/
writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
/* Turn on RTS flow control, turn off IXOFF flow control */
isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_RTSDTR);
isr_fcr &= ~(UART_EXAR654_EFR_IXOFF);
writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
/* Write old LCR value back out, which turns enhanced access off */
writeb(lcrb, &ch->ch_cls_uart->lcr);
/* Enable interrupts for RTS flow */
ier |= (UART_EXAR654_IER_RTSDTR);
writeb(ier, &ch->ch_cls_uart->ier);
/* Set the usual FIFO values */
writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_56 |
UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
&ch->ch_cls_uart->isr_fcr);
ch->ch_r_watermark = 4;
ch->ch_r_tlevel = 8;
}
static inline void cls_set_ixoff_flow_control(struct channel_t *ch)
{
unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
unsigned char ier = readb(&ch->ch_cls_uart->ier);
unsigned char isr_fcr = 0;
/*
* The Enhanced Register Set may only be accessed when
* the Line Control Register is set to 0xBFh.
*/
writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
/* Turn on IXOFF flow control, turn off RTS flow control */
isr_fcr |= (UART_EXAR654_EFR_ECB | UART_EXAR654_EFR_IXOFF);
isr_fcr &= ~(UART_EXAR654_EFR_RTSDTR);
writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
/* Now set our current start/stop chars while in enhanced mode */
writeb(ch->ch_startc, &ch->ch_cls_uart->mcr);
writeb(0, &ch->ch_cls_uart->lsr);
writeb(ch->ch_stopc, &ch->ch_cls_uart->msr);
writeb(0, &ch->ch_cls_uart->spr);
/* Write old LCR value back out, which turns enhanced access off */
writeb(lcrb, &ch->ch_cls_uart->lcr);
/* Disable interrupts for RTS flow */
ier &= ~(UART_EXAR654_IER_RTSDTR);
writeb(ier, &ch->ch_cls_uart->ier);
/* Set the usual FIFO values */
writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
&ch->ch_cls_uart->isr_fcr);
}
static inline void cls_set_no_input_flow_control(struct channel_t *ch)
{
unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
unsigned char ier = readb(&ch->ch_cls_uart->ier);
unsigned char isr_fcr = 0;
/*
* The Enhanced Register Set may only be accessed when
* the Line Control Register is set to 0xBFh.
*/
writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
/* Turn off IXOFF flow control, turn off RTS flow control */
isr_fcr |= (UART_EXAR654_EFR_ECB);
isr_fcr &= ~(UART_EXAR654_EFR_RTSDTR | UART_EXAR654_EFR_IXOFF);
writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
/* Write old LCR value back out, which turns enhanced access off */
writeb(lcrb, &ch->ch_cls_uart->lcr);
/* Disable interrupts for RTS flow */
ier &= ~(UART_EXAR654_IER_RTSDTR);
writeb(ier, &ch->ch_cls_uart->ier);
/* Set the usual FIFO values */
writeb((UART_FCR_ENABLE_FIFO), &ch->ch_cls_uart->isr_fcr);
writeb((UART_FCR_ENABLE_FIFO | UART_16654_FCR_RXTRIGGER_16 |
UART_16654_FCR_TXTRIGGER_16 | UART_FCR_CLEAR_RCVR),
&ch->ch_cls_uart->isr_fcr);
ch->ch_t_tlevel = 16;
ch->ch_r_tlevel = 16;
}
/*
* cls_clear_break.
* Determines whether its time to shut off break condition.
*
* No locks are assumed to be held when calling this function.
* channel lock is held and released in this function.
*/
static inline void cls_clear_break(struct channel_t *ch, int force)
{
unsigned long flags;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
spin_lock_irqsave(&ch->ch_lock, flags);
/* Bail if we aren't currently sending a break. */
if (!ch->ch_stop_sending_break) {
spin_unlock_irqrestore(&ch->ch_lock, flags);
return;
}
/* Turn break off, and unset some variables */
if (ch->ch_flags & CH_BREAK_SENDING) {
if (time_after(jiffies, ch->ch_stop_sending_break) || force) {
unsigned char temp = readb(&ch->ch_cls_uart->lcr);
writeb((temp & ~UART_LCR_SBC), &ch->ch_cls_uart->lcr);
ch->ch_flags &= ~(CH_BREAK_SENDING);
ch->ch_stop_sending_break = 0;
}
}
spin_unlock_irqrestore(&ch->ch_lock, flags);
}
/* Parse the ISR register for the specific port */
static inline void cls_parse_isr(struct dgnc_board *brd, uint port)
{
struct channel_t *ch;
unsigned char isr = 0;
unsigned long flags;
/*
* No need to verify board pointer, it was already
* verified in the interrupt routine.
*/
if (port >= brd->nasync)
return;
ch = brd->channels[port];
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
/* Here we try to figure out what caused the interrupt to happen */
while (1) {
isr = readb(&ch->ch_cls_uart->isr_fcr);
/* Bail if no pending interrupt on port */
if (isr & UART_IIR_NO_INT)
break;
/* Receive Interrupt pending */
if (isr & (UART_IIR_RDI | UART_IIR_RDI_TIMEOUT)) {
/* Read data from uart -> queue */
brd->intr_rx++;
ch->ch_intr_rx++;
cls_copy_data_from_uart_to_queue(ch);
dgnc_check_queue_flow_control(ch);
}
/* Transmit Hold register empty pending */
if (isr & UART_IIR_THRI) {
/* Transfer data (if any) from Write Queue -> UART. */
spin_lock_irqsave(&ch->ch_lock, flags);
ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
brd->intr_tx++;
ch->ch_intr_tx++;
spin_unlock_irqrestore(&ch->ch_lock, flags);
cls_copy_data_from_queue_to_uart(ch);
}
/* CTS/RTS change of state */
if (isr & UART_IIR_CTSRTS) {
brd->intr_modem++;
ch->ch_intr_modem++;
/*
* Don't need to do anything, the cls_parse_modem
* below will grab the updated modem signals.
*/
}
/* Parse any modem signal changes */
cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));
}
}
/*
* cls_param()
* Send any/all changes to the line to the UART.
*/
static void cls_param(struct tty_struct *tty)
{
unsigned char lcr = 0;
unsigned char uart_lcr = 0;
unsigned char ier = 0;
unsigned char uart_ier = 0;
uint baud = 9600;
int quot = 0;
struct dgnc_board *bd;
struct channel_t *ch;
struct un_t *un;
if (!tty || tty->magic != TTY_MAGIC)
return;
un = (struct un_t *) tty->driver_data;
if (!un || un->magic != DGNC_UNIT_MAGIC)
return;
ch = un->un_ch;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
bd = ch->ch_bd;
if (!bd || bd->magic != DGNC_BOARD_MAGIC)
return;
/*
* If baud rate is zero, flush queues, and set mval to drop DTR.
*/
if ((ch->ch_c_cflag & (CBAUD)) == 0) {
ch->ch_r_head = 0;
ch->ch_r_tail = 0;
ch->ch_e_head = 0;
ch->ch_e_tail = 0;
ch->ch_w_head = 0;
ch->ch_w_tail = 0;
cls_flush_uart_write(ch);
cls_flush_uart_read(ch);
/* The baudrate is B0 so all modem lines are to be dropped. */
ch->ch_flags |= (CH_BAUD0);
ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
cls_assert_modem_signals(ch);
ch->ch_old_baud = 0;
return;
} else if (ch->ch_custom_speed) {
baud = ch->ch_custom_speed;
/* Handle transition from B0 */
if (ch->ch_flags & CH_BAUD0) {
ch->ch_flags &= ~(CH_BAUD0);
/*
* Bring back up RTS and DTR...
* Also handle RTS or DTR toggle if set.
*/
if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))
ch->ch_mostat |= (UART_MCR_RTS);
if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))
ch->ch_mostat |= (UART_MCR_DTR);
}
} else {
int iindex = 0;
int jindex = 0;
ulong bauds[4][16] = {
{ /* slowbaud */
0, 50, 75, 110,
134, 150, 200, 300,
600, 1200, 1800, 2400,
4800, 9600, 19200, 38400 },
{ /* slowbaud & CBAUDEX */
0, 57600, 115200, 230400,
460800, 150, 200, 921600,
600, 1200, 1800, 2400,
4800, 9600, 19200, 38400 },
{ /* fastbaud */
0, 57600, 76800, 115200,
131657, 153600, 230400, 460800,
921600, 1200, 1800, 2400,
4800, 9600, 19200, 38400 },
{ /* fastbaud & CBAUDEX */
0, 57600, 115200, 230400,
460800, 150, 200, 921600,
600, 1200, 1800, 2400,
4800, 9600, 19200, 38400 }
};
/*
* Only use the TXPrint baud rate if the terminal
* unit is NOT open
*/
if (!(ch->ch_tun.un_flags & UN_ISOPEN) &&
(un->un_type == DGNC_PRINT))
baud = C_BAUD(ch->ch_pun.un_tty) & 0xff;
else
baud = C_BAUD(ch->ch_tun.un_tty) & 0xff;
if (ch->ch_c_cflag & CBAUDEX)
iindex = 1;
if (ch->ch_digi.digi_flags & DIGI_FAST)
iindex += 2;
jindex = baud;
if ((iindex >= 0) && (iindex < 4) && (jindex >= 0) &&
(jindex < 16)) {
baud = bauds[iindex][jindex];
} else {
baud = 0;
}
if (baud == 0)
baud = 9600;
/* Handle transition from B0 */
if (ch->ch_flags & CH_BAUD0) {
ch->ch_flags &= ~(CH_BAUD0);
/*
* Bring back up RTS and DTR...
* Also handle RTS or DTR toggle if set.
*/
if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))
ch->ch_mostat |= (UART_MCR_RTS);
if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))
ch->ch_mostat |= (UART_MCR_DTR);
}
}
if (ch->ch_c_cflag & PARENB)
lcr |= UART_LCR_PARITY;
if (!(ch->ch_c_cflag & PARODD))
lcr |= UART_LCR_EPAR;
/*
* Not all platforms support mark/space parity,
* so this will hide behind an ifdef.
*/
#ifdef CMSPAR
if (ch->ch_c_cflag & CMSPAR)
lcr |= UART_LCR_SPAR;
#endif
if (ch->ch_c_cflag & CSTOPB)
lcr |= UART_LCR_STOP;
switch (ch->ch_c_cflag & CSIZE) {
case CS5:
lcr |= UART_LCR_WLEN5;
break;
case CS6:
lcr |= UART_LCR_WLEN6;
break;
case CS7:
lcr |= UART_LCR_WLEN7;
break;
case CS8:
default:
lcr |= UART_LCR_WLEN8;
break;
}
uart_ier = readb(&ch->ch_cls_uart->ier);
ier = uart_ier;
uart_lcr = readb(&ch->ch_cls_uart->lcr);
if (baud == 0)
baud = 9600;
quot = ch->ch_bd->bd_dividend / baud;
if (quot != 0 && ch->ch_old_baud != baud) {
ch->ch_old_baud = baud;
writeb(UART_LCR_DLAB, &ch->ch_cls_uart->lcr);
writeb((quot & 0xff), &ch->ch_cls_uart->txrx);
writeb((quot >> 8), &ch->ch_cls_uart->ier);
writeb(lcr, &ch->ch_cls_uart->lcr);
}
if (uart_lcr != lcr)
writeb(lcr, &ch->ch_cls_uart->lcr);
if (ch->ch_c_cflag & CREAD)
ier |= (UART_IER_RDI | UART_IER_RLSI);
else
ier &= ~(UART_IER_RDI | UART_IER_RLSI);
/*
* Have the UART interrupt on modem signal changes ONLY when
* we are in hardware flow control mode, or CLOCAL/FORCEDCD is not set.
*/
if ((ch->ch_digi.digi_flags & CTSPACE) ||
(ch->ch_digi.digi_flags & RTSPACE) ||
(ch->ch_c_cflag & CRTSCTS) ||
!(ch->ch_digi.digi_flags & DIGI_FORCEDCD) ||
!(ch->ch_c_cflag & CLOCAL))
ier |= UART_IER_MSI;
else
ier &= ~UART_IER_MSI;
ier |= UART_IER_THRI;
if (ier != uart_ier)
writeb(ier, &ch->ch_cls_uart->ier);
if (ch->ch_digi.digi_flags & CTSPACE || ch->ch_c_cflag & CRTSCTS) {
cls_set_cts_flow_control(ch);
} else if (ch->ch_c_iflag & IXON) {
/*
* If start/stop is set to disable, then we should
* disable flow control
*/
if ((ch->ch_startc == _POSIX_VDISABLE) ||
(ch->ch_stopc == _POSIX_VDISABLE))
cls_set_no_output_flow_control(ch);
else
cls_set_ixon_flow_control(ch);
} else {
cls_set_no_output_flow_control(ch);
}
if (ch->ch_digi.digi_flags & RTSPACE || ch->ch_c_cflag & CRTSCTS) {
cls_set_rts_flow_control(ch);
} else if (ch->ch_c_iflag & IXOFF) {
/*
* If start/stop is set to disable, then we should disable
* flow control
*/
if ((ch->ch_startc == _POSIX_VDISABLE) ||
(ch->ch_stopc == _POSIX_VDISABLE))
cls_set_no_input_flow_control(ch);
else
cls_set_ixoff_flow_control(ch);
} else {
cls_set_no_input_flow_control(ch);
}
cls_assert_modem_signals(ch);
/* Get current status of the modem signals now */
cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));
}
/*
* Our board poller function.
*/
static void cls_tasklet(unsigned long data)
{
struct dgnc_board *bd = (struct dgnc_board *) data;
struct channel_t *ch;
unsigned long flags;
int i;
int state = 0;
int ports = 0;
if (!bd || bd->magic != DGNC_BOARD_MAGIC)
return;
/* Cache a couple board values */
spin_lock_irqsave(&bd->bd_lock, flags);
state = bd->state;
ports = bd->nasync;
spin_unlock_irqrestore(&bd->bd_lock, flags);
/*
* Do NOT allow the interrupt routine to read the intr registers
* Until we release this lock.
*/
spin_lock_irqsave(&bd->bd_intr_lock, flags);
/*
* If board is ready, parse deeper to see if there is anything to do.
*/
if ((state == BOARD_READY) && (ports > 0)) {
/* Loop on each port */
for (i = 0; i < ports; i++) {
ch = bd->channels[i];
if (!ch)
continue;
/*
* NOTE: Remember you CANNOT hold any channel
* locks when calling input.
* During input processing, its possible we
* will call ld, which might do callbacks back
* into us.
*/
dgnc_input(ch);
/*
* Channel lock is grabbed and then released
* inside this routine.
*/
cls_copy_data_from_queue_to_uart(ch);
dgnc_wakeup_writes(ch);
/*
* Check carrier function.
*/
dgnc_carrier(ch);
/*
* The timing check of turning off the break is done
* inside clear_break()
*/
if (ch->ch_stop_sending_break)
cls_clear_break(ch, 0);
}
}
spin_unlock_irqrestore(&bd->bd_intr_lock, flags);
}
/*
* cls_intr()
*
* Classic specific interrupt handler.
*/
static irqreturn_t cls_intr(int irq, void *voidbrd)
{
struct dgnc_board *brd = voidbrd;
uint i = 0;
unsigned char poll_reg;
unsigned long flags;
/*
* Check to make sure it didn't receive interrupt with a null board
* associated or a board pointer that wasn't ours.
*/
if (!brd || brd->magic != DGNC_BOARD_MAGIC)
return IRQ_NONE;
spin_lock_irqsave(&brd->bd_intr_lock, flags);
brd->intr_count++;
/*
* Check the board's global interrupt offset to see if we
* we actually do have an interrupt pending for us.
*/
poll_reg = readb(brd->re_map_membase + UART_CLASSIC_POLL_ADDR_OFFSET);
/* If 0, no interrupts pending */
if (!poll_reg) {
spin_unlock_irqrestore(&brd->bd_intr_lock, flags);
return IRQ_NONE;
}
/* Parse each port to find out what caused the interrupt */
for (i = 0; i < brd->nasync; i++)
cls_parse_isr(brd, i);
/*
* Schedule tasklet to more in-depth servicing at a better time.
*/
tasklet_schedule(&brd->helper_tasklet);
spin_unlock_irqrestore(&brd->bd_intr_lock, flags);
return IRQ_HANDLED;
}
static void cls_disable_receiver(struct channel_t *ch)
{
unsigned char tmp = readb(&ch->ch_cls_uart->ier);
tmp &= ~(UART_IER_RDI);
writeb(tmp, &ch->ch_cls_uart->ier);
}
static void cls_enable_receiver(struct channel_t *ch)
{
unsigned char tmp = readb(&ch->ch_cls_uart->ier);
tmp |= (UART_IER_RDI);
writeb(tmp, &ch->ch_cls_uart->ier);
}
static void cls_copy_data_from_uart_to_queue(struct channel_t *ch)
{
int qleft = 0;
unsigned char linestatus = 0;
unsigned char error_mask = 0;
ushort head;
ushort tail;
unsigned long flags;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
spin_lock_irqsave(&ch->ch_lock, flags);
/* cache head and tail of queue */
head = ch->ch_r_head;
tail = ch->ch_r_tail;
/* Store how much space we have left in the queue */
qleft = (tail - head - 1);
if (qleft < 0)
qleft += RQUEUEMASK + 1;
/*
* Create a mask to determine whether we should
* insert the character (if any) into our queue.
*/
if (ch->ch_c_iflag & IGNBRK)
error_mask |= UART_LSR_BI;
while (1) {
linestatus = readb(&ch->ch_cls_uart->lsr);
if (!(linestatus & (UART_LSR_DR)))
break;
/*
* Discard character if we are ignoring the error mask.
*/
if (linestatus & error_mask) {
unsigned char discard;
linestatus = 0;
discard = readb(&ch->ch_cls_uart->txrx);
continue;
}
/*
* If our queue is full, we have no choice but to drop some
* data. The assumption is that HWFLOW or SWFLOW should have
* stopped things way way before we got to this point.
*
* I decided that I wanted to ditch the oldest data first,
* I hope thats okay with everyone? Yes? Good.
*/
while (qleft < 1) {
tail = (tail + 1) & RQUEUEMASK;
ch->ch_r_tail = tail;
ch->ch_err_overrun++;
qleft++;
}
ch->ch_equeue[head] = linestatus & (UART_LSR_BI | UART_LSR_PE
| UART_LSR_FE);
ch->ch_rqueue[head] = readb(&ch->ch_cls_uart->txrx);
qleft--;
if (ch->ch_equeue[head] & UART_LSR_PE)
ch->ch_err_parity++;
if (ch->ch_equeue[head] & UART_LSR_BI)
ch->ch_err_break++;
if (ch->ch_equeue[head] & UART_LSR_FE)
ch->ch_err_frame++;
/* Add to, and flip head if needed */
head = (head + 1) & RQUEUEMASK;
ch->ch_rxcount++;
}
/*
* Write new final heads to channel structure.
*/
ch->ch_r_head = head & RQUEUEMASK;
ch->ch_e_head = head & EQUEUEMASK;
spin_unlock_irqrestore(&ch->ch_lock, flags);
}
/*
* This function basically goes to sleep for secs, or until
* it gets signalled that the port has fully drained.
*/
static int cls_drain(struct tty_struct *tty, uint seconds)
{
unsigned long flags;
struct channel_t *ch;
struct un_t *un;
if (!tty || tty->magic != TTY_MAGIC)
return -ENXIO;
un = (struct un_t *) tty->driver_data;
if (!un || un->magic != DGNC_UNIT_MAGIC)
return -ENXIO;
ch = un->un_ch;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return -ENXIO;
spin_lock_irqsave(&ch->ch_lock, flags);
un->un_flags |= UN_EMPTY;
spin_unlock_irqrestore(&ch->ch_lock, flags);
/*
* NOTE: Do something with time passed in.
*/
/* If ret is non-zero, user ctrl-c'ed us */
return wait_event_interruptible(un->un_flags_wait,
((un->un_flags & UN_EMPTY) == 0));
}
/* Channel lock MUST be held before calling this function! */
static void cls_flush_uart_write(struct channel_t *ch)
{
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT),
&ch->ch_cls_uart->isr_fcr);
udelay(10);
ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
}
/* Channel lock MUST be held before calling this function! */
static void cls_flush_uart_read(struct channel_t *ch)
{
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
/*
* For complete POSIX compatibility, we should be purging the
* read FIFO in the UART here.
*
* However, clearing the read FIFO (UART_FCR_CLEAR_RCVR) also
* incorrectly flushes write data as well as just basically trashing the
* FIFO.
*
* Presumably, this is a bug in this UART.
*/
udelay(10);
}
static void cls_copy_data_from_queue_to_uart(struct channel_t *ch)
{
ushort head;
ushort tail;
int n;
int qlen;
uint len_written = 0;
unsigned long flags;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
spin_lock_irqsave(&ch->ch_lock, flags);
/* No data to write to the UART */
if (ch->ch_w_tail == ch->ch_w_head)
goto exit_unlock;
/* If port is "stopped", don't send any data to the UART */
if ((ch->ch_flags & CH_FORCED_STOP) ||
(ch->ch_flags & CH_BREAK_SENDING))
goto exit_unlock;
if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))
goto exit_unlock;
n = 32;
/* cache head and tail of queue */
head = ch->ch_w_head & WQUEUEMASK;
tail = ch->ch_w_tail & WQUEUEMASK;
qlen = (head - tail) & WQUEUEMASK;
/* Find minimum of the FIFO space, versus queue length */
n = min(n, qlen);
while (n > 0) {
/*
* If RTS Toggle mode is on, turn on RTS now if not already set,
* and make sure we get an event when the data transfer has
* completed.
*/
if (ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE) {
if (!(ch->ch_mostat & UART_MCR_RTS)) {
ch->ch_mostat |= (UART_MCR_RTS);
cls_assert_modem_signals(ch);
}
ch->ch_tun.un_flags |= (UN_EMPTY);
}
/*
* If DTR Toggle mode is on, turn on DTR now if not already set,
* and make sure we get an event when the data transfer has
* completed.
*/
if (ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE) {
if (!(ch->ch_mostat & UART_MCR_DTR)) {
ch->ch_mostat |= (UART_MCR_DTR);
cls_assert_modem_signals(ch);
}
ch->ch_tun.un_flags |= (UN_EMPTY);
}
writeb(ch->ch_wqueue[ch->ch_w_tail], &ch->ch_cls_uart->txrx);
ch->ch_w_tail++;
ch->ch_w_tail &= WQUEUEMASK;
ch->ch_txcount++;
len_written++;
n--;
}
if (len_written > 0)
ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
exit_unlock:
spin_unlock_irqrestore(&ch->ch_lock, flags);
}
static void cls_parse_modem(struct channel_t *ch, unsigned char signals)
{
unsigned char msignals = signals;
unsigned long flags;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
/*
* Do altpin switching. Altpin switches DCD and DSR.
* This prolly breaks DSRPACE, so we should be more clever here.
*/
spin_lock_irqsave(&ch->ch_lock, flags);
if (ch->ch_digi.digi_flags & DIGI_ALTPIN) {
unsigned char mswap = signals;
if (mswap & UART_MSR_DDCD) {
msignals &= ~UART_MSR_DDCD;
msignals |= UART_MSR_DDSR;
}
if (mswap & UART_MSR_DDSR) {
msignals &= ~UART_MSR_DDSR;
msignals |= UART_MSR_DDCD;
}
if (mswap & UART_MSR_DCD) {
msignals &= ~UART_MSR_DCD;
msignals |= UART_MSR_DSR;
}
if (mswap & UART_MSR_DSR) {
msignals &= ~UART_MSR_DSR;
msignals |= UART_MSR_DCD;
}
}
spin_unlock_irqrestore(&ch->ch_lock, flags);
/*
* Scrub off lower bits. They signify delta's, which I don't
* care about
*/
signals &= 0xf0;
spin_lock_irqsave(&ch->ch_lock, flags);
if (msignals & UART_MSR_DCD)
ch->ch_mistat |= UART_MSR_DCD;
else
ch->ch_mistat &= ~UART_MSR_DCD;
if (msignals & UART_MSR_DSR)
ch->ch_mistat |= UART_MSR_DSR;
else
ch->ch_mistat &= ~UART_MSR_DSR;
if (msignals & UART_MSR_RI)
ch->ch_mistat |= UART_MSR_RI;
else
ch->ch_mistat &= ~UART_MSR_RI;
if (msignals & UART_MSR_CTS)
ch->ch_mistat |= UART_MSR_CTS;
else
ch->ch_mistat &= ~UART_MSR_CTS;
spin_unlock_irqrestore(&ch->ch_lock, flags);
}
/* Make the UART raise any of the output signals we want up */
static void cls_assert_modem_signals(struct channel_t *ch)
{
unsigned char out;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
out = ch->ch_mostat;
if (ch->ch_flags & CH_LOOPBACK)
out |= UART_MCR_LOOP;
writeb(out, &ch->ch_cls_uart->mcr);
/* Give time for the UART to actually drop the signals */
udelay(10);
}
static void cls_send_start_character(struct channel_t *ch)
{
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
if (ch->ch_startc != _POSIX_VDISABLE) {
ch->ch_xon_sends++;
writeb(ch->ch_startc, &ch->ch_cls_uart->txrx);
}
}
static void cls_send_stop_character(struct channel_t *ch)
{
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
if (ch->ch_stopc != _POSIX_VDISABLE) {
ch->ch_xoff_sends++;
writeb(ch->ch_stopc, &ch->ch_cls_uart->txrx);
}
}
/* Inits UART */
static void cls_uart_init(struct channel_t *ch)
{
unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
unsigned char isr_fcr = 0;
writeb(0, &ch->ch_cls_uart->ier);
/*
* The Enhanced Register Set may only be accessed when
* the Line Control Register is set to 0xBFh.
*/
writeb(UART_EXAR654_ENHANCED_REGISTER_SET, &ch->ch_cls_uart->lcr);
isr_fcr = readb(&ch->ch_cls_uart->isr_fcr);
/* Turn on Enhanced/Extended controls */
isr_fcr |= (UART_EXAR654_EFR_ECB);
writeb(isr_fcr, &ch->ch_cls_uart->isr_fcr);
/* Write old LCR value back out, which turns enhanced access off */
writeb(lcrb, &ch->ch_cls_uart->lcr);
/* Clear out UART and FIFO */
readb(&ch->ch_cls_uart->txrx);
writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT),
&ch->ch_cls_uart->isr_fcr);
udelay(10);
ch->ch_flags |= (CH_FIFO_ENABLED | CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
readb(&ch->ch_cls_uart->lsr);
readb(&ch->ch_cls_uart->msr);
}
/*
* Turns off UART.
*/
static void cls_uart_off(struct channel_t *ch)
{
writeb(0, &ch->ch_cls_uart->ier);
}
/*
* cls_get_uarts_bytes_left.
* Returns 0 is nothing left in the FIFO, returns 1 otherwise.
*
* The channel lock MUST be held by the calling function.
*/
static uint cls_get_uart_bytes_left(struct channel_t *ch)
{
unsigned char left = 0;
unsigned char lsr = 0;
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return 0;
lsr = readb(&ch->ch_cls_uart->lsr);
/* Determine whether the Transmitter is empty or not */
if (!(lsr & UART_LSR_TEMT)) {
if (ch->ch_flags & CH_TX_FIFO_EMPTY)
tasklet_schedule(&ch->ch_bd->helper_tasklet);
left = 1;
} else {
ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
left = 0;
}
return left;
}
/*
* cls_send_break.
* Starts sending a break thru the UART.
*
* The channel lock MUST be held by the calling function.
*/
static void cls_send_break(struct channel_t *ch, int msecs)
{
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
/*
* If we receive a time of 0, this means turn off the break.
*/
if (msecs == 0) {
/* Turn break off, and unset some variables */
if (ch->ch_flags & CH_BREAK_SENDING) {
unsigned char temp = readb(&ch->ch_cls_uart->lcr);
writeb((temp & ~UART_LCR_SBC), &ch->ch_cls_uart->lcr);
ch->ch_flags &= ~(CH_BREAK_SENDING);
ch->ch_stop_sending_break = 0;
}
return;
}
/*
* Set the time we should stop sending the break.
* If we are already sending a break, toss away the existing
* time to stop, and use this new value instead.
*/
ch->ch_stop_sending_break = jiffies + dgnc_jiffies_from_ms(msecs);
/* Tell the UART to start sending the break */
if (!(ch->ch_flags & CH_BREAK_SENDING)) {
unsigned char temp = readb(&ch->ch_cls_uart->lcr);
writeb((temp | UART_LCR_SBC), &ch->ch_cls_uart->lcr);
ch->ch_flags |= (CH_BREAK_SENDING);
}
}
/*
* cls_send_immediate_char.
* Sends a specific character as soon as possible to the UART,
* jumping over any bytes that might be in the write queue.
*
* The channel lock MUST be held by the calling function.
*/
static void cls_send_immediate_char(struct channel_t *ch, unsigned char c)
{
if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
return;
writeb(c, &ch->ch_cls_uart->txrx);
}
static void cls_vpd(struct dgnc_board *brd)
{
ulong vpdbase; /* Start of io base of the card */
u8 __iomem *re_map_vpdbase;/* Remapped memory of the card */
int i = 0;
vpdbase = pci_resource_start(brd->pdev, 3);
/* No VPD */
if (!vpdbase)
return;
re_map_vpdbase = ioremap(vpdbase, 0x400);
if (!re_map_vpdbase)
return;
/* Store the VPD into our buffer */
for (i = 0; i < 0x40; i++) {
brd->vpd[i] = readb(re_map_vpdbase + i);
pr_info("%x ", brd->vpd[i]);
}
pr_info("\n");
if (re_map_vpdbase)
iounmap(re_map_vpdbase);
}