// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2003 Digi International (www.digi.com)
* Scott H Kilau <Scott_Kilau at digi dot com>
*
* NOTE TO LINUX KERNEL HACKERS: DO NOT REFORMAT THIS CODE!
*
* This is shared code between Digi's CVS archive and the
* Linux Kernel sources.
* Changing the source just for reformatting needlessly breaks
* our CVS diff history.
*
* Send any bug fixes/changes to: Eng.Linux at digi dot com.
* Thank you.
*
*/
#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 <linux/tty.h>
#include "jsm.h" /* Driver main header file */
static struct {
unsigned int rate;
unsigned int cflag;
} baud_rates[] = {
{ 921600, B921600 },
{ 460800, B460800 },
{ 230400, B230400 },
{ 115200, B115200 },
{ 57600, B57600 },
{ 38400, B38400 },
{ 19200, B19200 },
{ 9600, B9600 },
{ 4800, B4800 },
{ 2400, B2400 },
{ 1200, B1200 },
{ 600, B600 },
{ 300, B300 },
{ 200, B200 },
{ 150, B150 },
{ 134, B134 },
{ 110, B110 },
{ 75, B75 },
{ 50, B50 },
};
static void cls_set_cts_flow_control(struct jsm_channel *ch)
{
u8 lcrb = readb(&ch->ch_cls_uart->lcr);
u8 ier = readb(&ch->ch_cls_uart->ier);
u8 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 void cls_set_ixon_flow_control(struct jsm_channel *ch)
{
u8 lcrb = readb(&ch->ch_cls_uart->lcr);
u8 ier = readb(&ch->ch_cls_uart->ier);
u8 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 void cls_set_no_output_flow_control(struct jsm_channel *ch)
{
u8 lcrb = readb(&ch->ch_cls_uart->lcr);
u8 ier = readb(&ch->ch_cls_uart->ier);
u8 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 void cls_set_rts_flow_control(struct jsm_channel *ch)
{
u8 lcrb = readb(&ch->ch_cls_uart->lcr);
u8 ier = readb(&ch->ch_cls_uart->ier);
u8 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 void cls_set_ixoff_flow_control(struct jsm_channel *ch)
{
u8 lcrb = readb(&ch->ch_cls_uart->lcr);
u8 ier = readb(&ch->ch_cls_uart->ier);
u8 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 void cls_set_no_input_flow_control(struct jsm_channel *ch)
{
u8 lcrb = readb(&ch->ch_cls_uart->lcr);
u8 ier = readb(&ch->ch_cls_uart->ier);
u8 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 void cls_clear_break(struct jsm_channel *ch)
{
unsigned long lock_flags;
spin_lock_irqsave(&ch->ch_lock, lock_flags);
/* Turn break off, and unset some variables */
if (ch->ch_flags & CH_BREAK_SENDING) {
u8 temp = readb(&ch->ch_cls_uart->lcr);
writeb((temp & ~UART_LCR_SBC), &ch->ch_cls_uart->lcr);
ch->ch_flags &= ~(CH_BREAK_SENDING);
jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
"clear break Finishing UART_LCR_SBC! finished: %lx\n",
jiffies);
}
spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
}
static void cls_disable_receiver(struct jsm_channel *ch)
{
u8 tmp = readb(&ch->ch_cls_uart->ier);
tmp &= ~(UART_IER_RDI);
writeb(tmp, &ch->ch_cls_uart->ier);
}
static void cls_enable_receiver(struct jsm_channel *ch)
{
u8 tmp = readb(&ch->ch_cls_uart->ier);
tmp |= (UART_IER_RDI);
writeb(tmp, &ch->ch_cls_uart->ier);
}
/* Make the UART raise any of the output signals we want up */
static void cls_assert_modem_signals(struct jsm_channel *ch)
{
if (!ch)
return;
writeb(ch->ch_mostat, &ch->ch_cls_uart->mcr);
}
static void cls_copy_data_from_uart_to_queue(struct jsm_channel *ch)
{
int qleft = 0;
u8 linestatus;
u8 error_mask = 0;
u16 head;
u16 tail;
unsigned long flags;
if (!ch)
return;
spin_lock_irqsave(&ch->ch_lock, flags);
/* cache head and tail of queue */
head = ch->ch_r_head & RQUEUEMASK;
tail = ch->ch_r_tail & RQUEUEMASK;
ch->ch_cached_lsr = 0;
/* 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) {
/*
* Grab the linestatus register, we need to
* check to see if there is any data to read
*/
linestatus = readb(&ch->ch_cls_uart->lsr);
/* Break out if there is no data to fetch */
if (!(linestatus & UART_LSR_DR))
break;
/*
* Discard character if we are ignoring the error mask
* which in this case is the break signal.
*/
if (linestatus & error_mask) {
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);
}
static void cls_copy_data_from_queue_to_uart(struct jsm_channel *ch)
{
struct tty_port *tport;
int n;
u32 len_written = 0;
if (!ch)
return;
tport = &ch->uart_port.state->port;
/* If port is "stopped", don't send any data to the UART */
if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING))
return;
/* We have to do it this way, because of the EXAR TXFIFO count bug. */
if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))
return;
n = 32;
while (n > 0) {
unsigned char c;
if (!kfifo_get(&tport->xmit_fifo, &c))
break;
writeb(c, &ch->ch_cls_uart->txrx);
n--;
ch->ch_txcount++;
len_written++;
}
if (len_written > ch->ch_t_tlevel)
ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
if (kfifo_is_empty(&tport->xmit_fifo))
uart_write_wakeup(&ch->uart_port);
}
static void cls_parse_modem(struct jsm_channel *ch, u8 signals)
{
u8 msignals = signals;
jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
"neo_parse_modem: port: %d msignals: %x\n",
ch->ch_portnum, msignals);
/*
* Scrub off lower bits.
* They signify delta's, which I don't care about
* Keep DDCD and DDSR though
*/
msignals &= 0xf8;
if (msignals & UART_MSR_DDCD)
uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD);
if (msignals & UART_MSR_DDSR)
uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_CTS);
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;
jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
"Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
ch->ch_portnum,
!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD));
}
/* Parse the ISR register for the specific port */
static inline void cls_parse_isr(struct jsm_board *brd, uint port)
{
struct jsm_channel *ch;
u8 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)
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 */
cls_copy_data_from_uart_to_queue(ch);
jsm_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);
spin_unlock_irqrestore(&ch->ch_lock, flags);
cls_copy_data_from_queue_to_uart(ch);
}
/*
* CTS/RTS change of state:
* 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));
}
}
/* Channel lock MUST be held before calling this function! */
static void cls_flush_uart_write(struct jsm_channel *ch)
{
u8 tmp = 0;
u8 i = 0;
if (!ch)
return;
writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT),
&ch->ch_cls_uart->isr_fcr);
for (i = 0; i < 10; i++) {
/* Check to see if the UART feels it completely flushed FIFO */
tmp = readb(&ch->ch_cls_uart->isr_fcr);
if (tmp & UART_FCR_CLEAR_XMIT) {
jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
"Still flushing TX UART... i: %d\n", i);
udelay(10);
} else
break;
}
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 jsm_channel *ch)
{
if (!ch)
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_send_start_character(struct jsm_channel *ch)
{
if (!ch)
return;
if (ch->ch_startc != __DISABLED_CHAR) {
ch->ch_xon_sends++;
writeb(ch->ch_startc, &ch->ch_cls_uart->txrx);
}
}
static void cls_send_stop_character(struct jsm_channel *ch)
{
if (!ch)
return;
if (ch->ch_stopc != __DISABLED_CHAR) {
ch->ch_xoff_sends++;
writeb(ch->ch_stopc, &ch->ch_cls_uart->txrx);
}
}
/*
* cls_param()
* Send any/all changes to the line to the UART.
*/
static void cls_param(struct jsm_channel *ch)
{
u8 lcr = 0;
u8 uart_lcr = 0;
u8 ier = 0;
u32 baud = 9600;
int quot = 0;
struct jsm_board *bd;
int i;
unsigned int cflag;
bd = ch->ch_bd;
if (!bd)
return;
/*
* If baud rate is zero, flush queues, and set mval to drop DTR.
*/
if ((ch->ch_c_cflag & CBAUD) == B0) {
ch->ch_r_head = 0;
ch->ch_r_tail = 0;
ch->ch_e_head = 0;
ch->ch_e_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);
return;
}
cflag = C_BAUD(ch->uart_port.state->port.tty);
baud = 9600;
for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
if (baud_rates[i].cflag == cflag) {
baud = baud_rates[i].rate;
break;
}
}
if (ch->ch_flags & CH_BAUD0)
ch->ch_flags &= ~(CH_BAUD0);
if (ch->ch_c_cflag & PARENB)
lcr |= UART_LCR_PARITY;
if (!(ch->ch_c_cflag & PARODD))
lcr |= UART_LCR_EPAR;
if (ch->ch_c_cflag & CMSPAR)
lcr |= UART_LCR_SPAR;
if (ch->ch_c_cflag & CSTOPB)
lcr |= UART_LCR_STOP;
lcr |= UART_LCR_WLEN(tty_get_char_size(ch->ch_c_cflag));
ier = readb(&ch->ch_cls_uart->ier);
uart_lcr = readb(&ch->ch_cls_uart->lcr);
quot = ch->ch_bd->bd_dividend / baud;
if (quot != 0) {
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);
ier |= (UART_IER_THRI | UART_IER_MSI);
writeb(ier, &ch->ch_cls_uart->ier);
if (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 == __DISABLED_CHAR) ||
(ch->ch_stopc == __DISABLED_CHAR))
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_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 == __DISABLED_CHAR) ||
(ch->ch_stopc == __DISABLED_CHAR))
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));
}
/*
* cls_intr()
*
* Classic specific interrupt handler.
*/
static irqreturn_t cls_intr(int irq, void *voidbrd)
{
struct jsm_board *brd = voidbrd;
unsigned long lock_flags;
unsigned char uart_poll;
uint i = 0;
/* Lock out the slow poller from running on this board. */
spin_lock_irqsave(&brd->bd_intr_lock, lock_flags);
/*
* Check the board's global interrupt offset to see if we
* acctually do have an interrupt pending on us.
*/
uart_poll = readb(brd->re_map_membase + UART_CLASSIC_POLL_ADDR_OFFSET);
jsm_dbg(INTR, &brd->pci_dev, "%s:%d uart_poll: %x\n",
__FILE__, __LINE__, uart_poll);
if (!uart_poll) {
jsm_dbg(INTR, &brd->pci_dev,
"Kernel interrupted to me, but no pending interrupts...\n");
spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
return IRQ_NONE;
}
/* At this point, we have at least SOMETHING to service, dig further. */
/* Parse each port to find out what caused the interrupt */
for (i = 0; i < brd->nasync; i++)
cls_parse_isr(brd, i);
spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
return IRQ_HANDLED;
}
/* Inits UART */
static void cls_uart_init(struct jsm_channel *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 jsm_channel *ch)
{
/* Stop all interrupts from accurring. */
writeb(0, &ch->ch_cls_uart->ier);
}
/*
* 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 jsm_channel *ch)
{
/* Tell the UART to start sending the break */
if (!(ch->ch_flags & CH_BREAK_SENDING)) {
u8 temp = readb(&ch->ch_cls_uart->lcr);
writeb((temp | UART_LCR_SBC), &ch->ch_cls_uart->lcr);
ch->ch_flags |= (CH_BREAK_SENDING);
}
}
struct board_ops jsm_cls_ops = {
.intr = cls_intr,
.uart_init = cls_uart_init,
.uart_off = cls_uart_off,
.param = cls_param,
.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,
.clear_break = cls_clear_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,
};
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