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    SubjectRe: [ patch 3/5] drivers/serial/jsm: new serial device driver
    Arjan van de Ven wrote:

    >>Jeff pointed out several PCI posting errors last time. Before we used
    >>udelay and now we changed to readb/readl instead of udelay this time.
    >>But we only used PCI posting when we think maybe delay there.
    >>So we have to do PCI posting on every writeb?
    >>
    >>
    >not every
    >
    >
    >
    >>Do you have some rules for
    >>doing PCI posting while writeb? depends on what kind of registers?
    >>
    >>
    >
    >basically you need to do posting flushes after every write for which you
    >assume later on the hardware received the write. If you do 5 writes in a
    >row you don't need 5 flushes. If you do a read later always anyway you
    >don't need any flushes.
    >On the other side of the spectrum: if you do something to the hardware
    >and then wait for some event, you do need to flush that stuff.
    >So at minimum you want to make sure that at any point where you leave
    >the driver (to userspace or tty layer or ...) all writes have been
    >flushed. And at all points where you are going to wait for hardware
    >events.
    >
    >
    >
    >
    >
    Based on above all points, I audited the whole drvier for PCI posting
    issues.
    Just added several PCI posting while the driver has interfaces with tty
    layer.

    Thanks for your comments.
    wendy


    diff -Nuar linux-2.6.11.org/drivers/serial/jsm/jsm_neo.c linux-2.6.11.new/drivers/serial/jsm/jsm_neo.c
    --- linux-2.6.11.org/drivers/serial/jsm/jsm_neo.c 1969-12-31 18:00:00.000000000 -0600
    +++ linux-2.6.11.new/drivers/serial/jsm/jsm_neo.c 2005-03-11 16:26:47.442988256 -0600
    @@ -0,0 +1,1402 @@
    +/************************************************************************
    + * Copyright 2003 Digi International (www.digi.com)
    + *
    + * Copyright (C) 2004 IBM Corporation. All rights reserved.
    + *
    + * 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.
    + *
    + * You should have received a copy of the GNU General Public License
    + * along with this program; if not, write to the Free Software
    + * Foundation, Inc., 59 * Temple Place - Suite 330, Boston,
    + * MA 02111-1307, USA.
    + *
    + * Contact Information:
    + * Scott H Kilau <Scott_Kilau@digi.com>
    + * Wendy Xiong <wendyx@us.ltcfwd.linux.ibm.com>
    + *
    + ***********************************************************************/
    +#include <linux/delay.h> /* For udelay */
    +#include <linux/serial_reg.h> /* For the various UART offsets */
    +#include <linux/tty.h>
    +#include <linux/pci.h>
    +#include <asm/io.h>
    +
    +#include "jsm.h" /* Driver main header file */
    +
    +static u32 jsm_offset_table[8] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };
    +
    +static void neo_set_cts_flow_control(struct jsm_channel *ch)
    +{
    + u8 ier = readb(&ch->ch_neo_uart->ier);
    + u8 efr = readb(&ch->ch_neo_uart->efr);
    +
    + jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting CTSFLOW\n");
    +
    + /* Turn on auto CTS flow control */
    + ier |= (UART_17158_IER_CTSDSR);
    + efr |= (UART_17158_EFR_ECB | UART_17158_EFR_CTSDSR);
    +
    + /* Turn off auto Xon flow control */
    + efr &= ~(UART_17158_EFR_IXON);
    +
    + /* Why? Becuz Exar's spec says we have to zero it out before setting it */
    + writeb(0, &ch->ch_neo_uart->efr);
    +
    + /* Turn on UART enhanced bits */
    + writeb(efr, &ch->ch_neo_uart->efr);
    +
    + /* Turn on table D, with 8 char hi/low watermarks */
    + writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
    +
    + /* Feed the UART our trigger levels */
    + writeb(8, &ch->ch_neo_uart->tfifo);
    + ch->ch_t_tlevel = 8;
    +
    + writeb(ier, &ch->ch_neo_uart->ier);
    +}
    +
    +static void neo_set_rts_flow_control(struct jsm_channel *ch)
    +{
    + u8 ier = readb(&ch->ch_neo_uart->ier);
    + u8 efr = readb(&ch->ch_neo_uart->efr);
    +
    + jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting RTSFLOW\n");
    +
    + /* Turn on auto RTS flow control */
    + ier |= (UART_17158_IER_RTSDTR);
    + efr |= (UART_17158_EFR_ECB | UART_17158_EFR_RTSDTR);
    +
    + /* Turn off auto Xoff flow control */
    + ier &= ~(UART_17158_IER_XOFF);
    + efr &= ~(UART_17158_EFR_IXOFF);
    +
    + /* Why? Becuz Exar's spec says we have to zero it out before setting it */
    + writeb(0, &ch->ch_neo_uart->efr);
    +
    + /* Turn on UART enhanced bits */
    + writeb(efr, &ch->ch_neo_uart->efr);
    +
    + writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
    + ch->ch_r_watermark = 4;
    +
    + writeb(56, &ch->ch_neo_uart->rfifo);
    + ch->ch_r_tlevel = 56;
    +
    + writeb(ier, &ch->ch_neo_uart->ier);
    +
    + /*
    + * From the Neo UART spec sheet:
    + * The auto RTS/DTR function must be started by asserting
    + * RTS/DTR# output pin (MCR bit-0 or 1 to logic 1 after
    + * it is enabled.
    + */
    + ch->ch_mostat |= (UART_MCR_RTS);
    +}
    +
    +
    +static void neo_set_ixon_flow_control(struct jsm_channel *ch)
    +{
    + u8 ier = readb(&ch->ch_neo_uart->ier);
    + u8 efr = readb(&ch->ch_neo_uart->efr);
    +
    + jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting IXON FLOW\n");
    +
    + /* Turn off auto CTS flow control */
    + ier &= ~(UART_17158_IER_CTSDSR);
    + efr &= ~(UART_17158_EFR_CTSDSR);
    +
    + /* Turn on auto Xon flow control */
    + efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXON);
    +
    + /* Why? Becuz Exar's spec says we have to zero it out before setting it */
    + writeb(0, &ch->ch_neo_uart->efr);
    +
    + /* Turn on UART enhanced bits */
    + writeb(efr, &ch->ch_neo_uart->efr);
    +
    + writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
    + ch->ch_r_watermark = 4;
    +
    + writeb(32, &ch->ch_neo_uart->rfifo);
    + ch->ch_r_tlevel = 32;
    +
    + /* Tell UART what start/stop chars it should be looking for */
    + writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
    + writeb(0, &ch->ch_neo_uart->xonchar2);
    +
    + writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
    + writeb(0, &ch->ch_neo_uart->xoffchar2);
    +
    + writeb(ier, &ch->ch_neo_uart->ier);
    +}
    +
    +static void neo_set_ixoff_flow_control(struct jsm_channel *ch)
    +{
    + u8 ier = readb(&ch->ch_neo_uart->ier);
    + u8 efr = readb(&ch->ch_neo_uart->efr);
    +
    + jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting IXOFF FLOW\n");
    +
    + /* Turn off auto RTS flow control */
    + ier &= ~(UART_17158_IER_RTSDTR);
    + efr &= ~(UART_17158_EFR_RTSDTR);
    +
    + /* Turn on auto Xoff flow control */
    + ier |= (UART_17158_IER_XOFF);
    + efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
    +
    + /* Why? Becuz Exar's spec says we have to zero it out before setting it */
    + writeb(0, &ch->ch_neo_uart->efr);
    +
    + /* Turn on UART enhanced bits */
    + writeb(efr, &ch->ch_neo_uart->efr);
    +
    + /* Turn on table D, with 8 char hi/low watermarks */
    + writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
    +
    + writeb(8, &ch->ch_neo_uart->tfifo);
    + ch->ch_t_tlevel = 8;
    +
    + /* Tell UART what start/stop chars it should be looking for */
    + writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
    + writeb(0, &ch->ch_neo_uart->xonchar2);
    +
    + writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
    + writeb(0, &ch->ch_neo_uart->xoffchar2);
    +
    + writeb(ier, &ch->ch_neo_uart->ier);
    +}
    +
    +static void neo_set_no_input_flow_control(struct jsm_channel *ch)
    +{
    + u8 ier = readb(&ch->ch_neo_uart->ier);
    + u8 efr = readb(&ch->ch_neo_uart->efr);
    +
    + jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Unsetting Input FLOW\n");
    +
    + /* Turn off auto RTS flow control */
    + ier &= ~(UART_17158_IER_RTSDTR);
    + efr &= ~(UART_17158_EFR_RTSDTR);
    +
    + /* Turn off auto Xoff flow control */
    + ier &= ~(UART_17158_IER_XOFF);
    + if (ch->ch_c_iflag & IXON)
    + efr &= ~(UART_17158_EFR_IXOFF);
    + else
    + efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
    +
    + /* Why? Becuz Exar's spec says we have to zero it out before setting it */
    + writeb(0, &ch->ch_neo_uart->efr);
    +
    + /* Turn on UART enhanced bits */
    + writeb(efr, &ch->ch_neo_uart->efr);
    +
    + /* Turn on table D, with 8 char hi/low watermarks */
    + writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
    +
    + ch->ch_r_watermark = 0;
    +
    + writeb(16, &ch->ch_neo_uart->tfifo);
    + ch->ch_t_tlevel = 16;
    +
    + writeb(16, &ch->ch_neo_uart->rfifo);
    + ch->ch_r_tlevel = 16;
    +
    + writeb(ier, &ch->ch_neo_uart->ier);
    +}
    +
    +static void neo_set_no_output_flow_control(struct jsm_channel *ch)
    +{
    + u8 ier = readb(&ch->ch_neo_uart->ier);
    + u8 efr = readb(&ch->ch_neo_uart->efr);
    +
    + jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Unsetting Output FLOW\n");
    +
    + /* Turn off auto CTS flow control */
    + ier &= ~(UART_17158_IER_CTSDSR);
    + efr &= ~(UART_17158_EFR_CTSDSR);
    +
    + /* Turn off auto Xon flow control */
    + if (ch->ch_c_iflag & IXOFF)
    + efr &= ~(UART_17158_EFR_IXON);
    + else
    + efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXON);
    +
    + /* Why? Becuz Exar's spec says we have to zero it out before setting it */
    + writeb(0, &ch->ch_neo_uart->efr);
    +
    + /* Turn on UART enhanced bits */
    + writeb(efr, &ch->ch_neo_uart->efr);
    +
    + /* Turn on table D, with 8 char hi/low watermarks */
    + writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
    +
    + ch->ch_r_watermark = 0;
    +
    + writeb(16, &ch->ch_neo_uart->tfifo);
    + ch->ch_t_tlevel = 16;
    +
    + writeb(16, &ch->ch_neo_uart->rfifo);
    + ch->ch_r_tlevel = 16;
    +
    + writeb(ier, &ch->ch_neo_uart->ier);
    +}
    +
    +static inline void neo_set_new_start_stop_chars(struct jsm_channel *ch)
    +{
    +
    + /* if hardware flow control is set, then skip this whole thing */
    + if (ch->ch_c_cflag & CRTSCTS)
    + return;
    +
    + jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "start\n");
    +
    + /* Tell UART what start/stop chars it should be looking for */
    + writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
    + writeb(0, &ch->ch_neo_uart->xonchar2);
    +
    + writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
    + writeb(0, &ch->ch_neo_uart->xoffchar2);
    +}
    +
    +static void neo_copy_data_from_uart_to_queue(struct jsm_channel *ch)
    +{
    + int qleft = 0;
    + u8 linestatus = 0;
    + u8 error_mask = 0;
    + int n = 0;
    + int total = 0;
    + u16 head;
    + u16 tail;
    +
    + if (!ch)
    + return;
    +
    + /* cache head and tail of queue */
    + head = ch->ch_r_head & RQUEUEMASK;
    + tail = ch->ch_r_tail & RQUEUEMASK;
    +
    + /* Get our cached LSR */
    + linestatus = ch->ch_cached_lsr;
    + ch->ch_cached_lsr = 0;
    +
    + /* Store how much space we have left in the queue */
    + if ((qleft = tail - head - 1) < 0)
    + qleft += RQUEUEMASK + 1;
    +
    + /*
    + * If the UART is not in FIFO mode, force the FIFO copy to
    + * NOT be run, by setting total to 0.
    + *
    + * On the other hand, if the UART IS in FIFO mode, then ask
    + * the UART to give us an approximation of data it has RX'ed.
    + */
    + if (!(ch->ch_flags & CH_FIFO_ENABLED))
    + total = 0;
    + else {
    + total = readb(&ch->ch_neo_uart->rfifo);
    +
    + /*
    + * EXAR chip bug - RX FIFO COUNT - Fudge factor.
    + *
    + * This resolves a problem/bug with the Exar chip that sometimes
    + * returns a bogus value in the rfifo register.
    + * The count can be any where from 0-3 bytes "off".
    + * Bizarre, but true.
    + */
    + total -= 3;
    + }
    +
    + /*
    + * Finally, bound the copy to make sure we don't overflow
    + * our own queue...
    + * The byte by byte copy loop below this loop this will
    + * deal with the queue overflow possibility.
    + */
    + total = min(total, qleft);
    +
    + while (total > 0) {
    + /*
    + * Grab the linestatus register, we need to check
    + * to see if there are any errors in the FIFO.
    + */
    + linestatus = readb(&ch->ch_neo_uart->lsr);
    +
    + /*
    + * Break out if there is a FIFO error somewhere.
    + * This will allow us to go byte by byte down below,
    + * finding the exact location of the error.
    + */
    + if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
    + break;
    +
    + /* Make sure we don't go over the end of our queue */
    + n = min(((u32) total), (RQUEUESIZE - (u32) tail));
    +
    + /*
    + * Cut down n even further if needed, this is to fix
    + * a problem with memcpy_fromio() with the Neo on the
    + * IBM pSeries platform.
    + * 15 bytes max appears to be the magic number.
    + */
    + n = min((u32) n, (u32) 12);
    +
    + /*
    + * Since we are grabbing the linestatus register, which
    + * will reset some bits after our read, we need to ensure
    + * we don't miss our TX FIFO emptys.
    + */
    + if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR))
    + ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
    +
    + linestatus = 0;
    +
    + /* Copy data from uart to the queue */
    + memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, n);
    + /*
    + * Since RX_FIFO_DATA_ERROR was 0, we are guarenteed
    + * that all the data currently in the FIFO is free of
    + * breaks and parity/frame/orun errors.
    + */
    + memset(ch->ch_equeue + head, 0, n);
    +
    + /* Add to and flip head if needed */
    + head = (head + n) & RQUEUEMASK;
    + total -= n;
    + qleft -= n;
    + ch->ch_rxcount += n;
    + }
    +
    + /*
    + * 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;
    +
    + /*
    + * Now cleanup any leftover bytes still in the UART.
    + * Also deal with any possible queue overflow here as well.
    + */
    + while (1) {
    +
    + /*
    + * Its possible we have a linestatus from the loop above
    + * this, so we "OR" on any extra bits.
    + */
    + linestatus |= readb(&ch->ch_neo_uart->lsr);
    +
    + /*
    + * If the chip tells us there is no more data pending to
    + * be read, we can then leave.
    + * But before we do, cache the linestatus, just in case.
    + */
    + if (!(linestatus & UART_LSR_DR)) {
    + ch->ch_cached_lsr = linestatus;
    + break;
    + }
    +
    + /* No need to store this bit */
    + linestatus &= ~UART_LSR_DR;
    +
    + /*
    + * Since we are grabbing the linestatus register, which
    + * will reset some bits after our read, we need to ensure
    + * we don't miss our TX FIFO emptys.
    + */
    + if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR)) {
    + linestatus &= ~(UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR);
    + ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
    + }
    +
    + /*
    + * Discard character if we are ignoring the error mask.
    + */
    + if (linestatus & error_mask) {
    + u8 discard;
    + linestatus = 0;
    + memcpy_fromio(&discard, &ch->ch_neo_uart->txrxburst, 1);
    + 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) {
    + jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
    + "Queue full, dropping DATA:%x LSR:%x\n",
    + ch->ch_rqueue[tail], ch->ch_equeue[tail]);
    +
    + ch->ch_r_tail = tail = (tail + 1) & RQUEUEMASK;
    + ch->ch_err_overrun++;
    + qleft++;
    + }
    +
    + memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, 1);
    + ch->ch_equeue[head] = (u8) linestatus;
    +
    + jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
    + "DATA/LSR pair: %x %x\n", ch->ch_rqueue[head], ch->ch_equeue[head]);
    +
    + /* Ditch any remaining linestatus value. */
    + linestatus = 0;
    +
    + /* Add to and flip head if needed */
    + head = (head + 1) & RQUEUEMASK;
    +
    + qleft--;
    + ch->ch_rxcount++;
    + }
    +
    + /*
    + * Write new final heads to channel structure.
    + */
    + ch->ch_r_head = head & RQUEUEMASK;
    + ch->ch_e_head = head & EQUEUEMASK;
    + jsm_input(ch);
    +}
    +
    +static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch)
    +{
    + u16 head;
    + u16 tail;
    + int n;
    + int s;
    + int qlen;
    + u32 len_written = 0;
    +
    + if (!ch)
    + return;
    +
    + /* No data to write to the UART */
    + if (ch->ch_w_tail == ch->ch_w_head)
    + return;
    +
    + /* 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;
    + /*
    + * If FIFOs are disabled. Send data directly to txrx register
    + */
    + if (!(ch->ch_flags & CH_FIFO_ENABLED)) {
    + u8 lsrbits = readb(&ch->ch_neo_uart->lsr);
    +
    + ch->ch_cached_lsr |= lsrbits;
    + if (ch->ch_cached_lsr & UART_LSR_THRE) {
    + ch->ch_cached_lsr &= ~(UART_LSR_THRE);
    +
    + writeb(ch->ch_wqueue[ch->ch_w_tail], &ch->ch_neo_uart->txrx);
    + jsm_printk(WRITE, INFO, &ch->ch_bd->pci_dev,
    + "Tx data: %x\n", ch->ch_wqueue[ch->ch_w_head]);
    + ch->ch_w_tail++;
    + ch->ch_w_tail &= WQUEUEMASK;
    + ch->ch_txcount++;
    + }
    + 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;
    +
    + len_written = 0;
    + n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel;
    +
    + /* 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) {
    +
    + s = ((head >= tail) ? head : WQUEUESIZE) - tail;
    + s = min(s, n);
    +
    + if (s <= 0)
    + break;
    +
    + memcpy_toio(&ch->ch_neo_uart->txrxburst, ch->ch_wqueue + tail, s);
    + /* Add and flip queue if needed */
    + tail = (tail + s) & WQUEUEMASK;
    + n -= s;
    + ch->ch_txcount += s;
    + len_written += s;
    + }
    +
    + /* Update the final tail */
    + ch->ch_w_tail = tail & WQUEUEMASK;
    +
    + if (len_written >= ch->ch_t_tlevel)
    + ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
    +
    + if (!jsm_tty_write(&ch->uart_port))
    + uart_write_wakeup(&ch->uart_port);
    +}
    +
    +static void neo_parse_modem(struct jsm_channel *ch, u8 signals)
    +{
    + u8 msignals = signals;
    +
    + jsm_printk(MSIGS, INFO, &ch->ch_bd->pci_dev,
    + "neo_parse_modem: port: %d msignals: %x\n", ch->ch_portnum, msignals);
    +
    + if (!ch)
    + return;
    +
    + /* Scrub off lower bits. They signify delta's, which I don't care about */
    + msignals &= 0xf0;
    +
    + 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_printk(MSIGS, INFO, &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));
    +}
    +
    +/* Make the UART raise any of the output signals we want up */
    +static void neo_assert_modem_signals(struct jsm_channel *ch)
    +{
    + u8 out;
    +
    + if (!ch)
    + return;
    +
    + out = ch->ch_mostat;
    +
    + writeb(out, &ch->ch_neo_uart->mcr);
    +
    + /* flush write operation */
    + readb(&ch->ch_neo_uart->mcr);
    +}
    +
    +/*
    + * Flush the WRITE FIFO on the Neo.
    + *
    + * NOTE: Channel lock MUST be held before calling this function!
    + */
    +static void neo_flush_uart_write(struct jsm_channel *ch)
    +{
    + u8 tmp = 0;
    + int i = 0;
    +
    + if (!ch)
    + return;
    +
    + writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
    +
    + for (i = 0; i < 10; i++) {
    +
    + /* Check to see if the UART feels it completely flushed the FIFO. */
    + tmp = readb(&ch->ch_neo_uart->isr_fcr);
    + if (tmp & 4) {
    + jsm_printk(IOCTL, INFO, &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);
    +}
    +
    +
    +/*
    + * Flush the READ FIFO on the Neo.
    + *
    + * NOTE: Channel lock MUST be held before calling this function!
    + */
    +static void neo_flush_uart_read(struct jsm_channel *ch)
    +{
    + u8 tmp = 0;
    + int i = 0;
    +
    + if (!ch)
    + return;
    +
    + writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr);
    +
    + for (i = 0; i < 10; i++) {
    +
    + /* Check to see if the UART feels it completely flushed the FIFO. */
    + tmp = readb(&ch->ch_neo_uart->isr_fcr);
    + if (tmp & 2) {
    + jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
    + "Still flushing RX UART... i: %d\n", i);
    + udelay(10);
    + }
    + else
    + break;
    + }
    +}
    +
    +/*
    + * No locks are assumed to be held when calling this function.
    + */
    +void neo_clear_break(struct jsm_channel *ch, int force)
    +{
    + u64 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_neo_uart->lcr);
    + writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr);
    +
    + ch->ch_flags &= ~(CH_BREAK_SENDING);
    + jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
    + "clear break Finishing UART_LCR_SBC! finished: %lx\n", jiffies);
    + }
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    +}
    +
    +/*
    + * Parse the ISR register.
    + */
    +static inline void neo_parse_isr(struct jsm_board *brd, u32 port)
    +{
    + struct jsm_channel *ch;
    + u8 isr;
    + u8 cause;
    + u64 lock_flags;
    +
    + if (!brd)
    + return;
    +
    + if (port > brd->maxports)
    + 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_neo_uart->isr_fcr);
    +
    + /* Bail if no pending interrupt */
    + if (isr & UART_IIR_NO_INT)
    + break;
    +
    + /*
    + * Yank off the upper 2 bits, which just show that the FIFO's are enabled.
    + */
    + isr &= ~(UART_17158_IIR_FIFO_ENABLED);
    +
    + jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
    + "%s:%d isr: %x\n", __FILE__, __LINE__, isr);
    +
    + if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) {
    + /* Read data from uart -> queue */
    + neo_copy_data_from_uart_to_queue(ch);
    +
    + /* Call our tty layer to enforce queue flow control if needed. */
    + spin_lock_irqsave(&ch->ch_lock, lock_flags);
    + jsm_check_queue_flow_control(ch);
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    + }
    +
    + if (isr & UART_IIR_THRI) {
    + /* Transfer data (if any) from Write Queue -> UART. */
    + spin_lock_irqsave(&ch->ch_lock, lock_flags);
    + ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    + neo_copy_data_from_queue_to_uart(ch);
    + }
    +
    + if (isr & UART_17158_IIR_XONXOFF) {
    + cause = readb(&ch->ch_neo_uart->xoffchar1);
    +
    + jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
    + "Port %d. Got ISR_XONXOFF: cause:%x\n", port, cause);
    +
    + /*
    + * Since the UART detected either an XON or
    + * XOFF match, we need to figure out which
    + * one it was, so we can suspend or resume data flow.
    + */
    + spin_lock_irqsave(&ch->ch_lock, lock_flags);
    + if (cause == UART_17158_XON_DETECT) {
    + /* Is output stopped right now, if so, resume it */
    + if (brd->channels[port]->ch_flags & CH_STOP) {
    + ch->ch_flags &= ~(CH_STOP);
    + }
    + jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
    + "Port %d. XON detected in incoming data\n", port);
    + }
    + else if (cause == UART_17158_XOFF_DETECT) {
    + if (!(brd->channels[port]->ch_flags & CH_STOP)) {
    + ch->ch_flags |= CH_STOP;
    + jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
    + "Setting CH_STOP\n");
    + }
    + jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
    + "Port: %d. XOFF detected in incoming data\n", port);
    + }
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    + }
    +
    + if (isr & UART_17158_IIR_HWFLOW_STATE_CHANGE) {
    + /*
    + * If we get here, this means the hardware is doing auto flow control.
    + * Check to see whether RTS/DTR or CTS/DSR caused this interrupt.
    + */
    + cause = readb(&ch->ch_neo_uart->mcr);
    +
    + /* Which pin is doing auto flow? RTS or DTR? */
    + spin_lock_irqsave(&ch->ch_lock, lock_flags);
    + if ((cause & 0x4) == 0) {
    + if (cause & UART_MCR_RTS)
    + ch->ch_mostat |= UART_MCR_RTS;
    + else
    + ch->ch_mostat &= ~(UART_MCR_RTS);
    + } else {
    + if (cause & UART_MCR_DTR)
    + ch->ch_mostat |= UART_MCR_DTR;
    + else
    + ch->ch_mostat &= ~(UART_MCR_DTR);
    + }
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    + }
    +
    + /* Parse any modem signal changes */
    + jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
    + "MOD_STAT: sending to parse_modem_sigs\n");
    + neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
    + }
    +}
    +
    +static inline void neo_parse_lsr(struct jsm_board *brd, u32 port)
    +{
    + struct jsm_channel *ch;
    + int linestatus;
    + u64 lock_flags;
    +
    + if (!brd)
    + return;
    +
    + if (port > brd->maxports)
    + return;
    +
    + ch = brd->channels[port];
    + if (!ch)
    + return;
    +
    + linestatus = readb(&ch->ch_neo_uart->lsr);
    +
    + jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
    + "%s:%d port: %d linestatus: %x\n", __FILE__, __LINE__, port, linestatus);
    +
    + ch->ch_cached_lsr |= linestatus;
    +
    + if (ch->ch_cached_lsr & UART_LSR_DR) {
    + /* Read data from uart -> queue */
    + neo_copy_data_from_uart_to_queue(ch);
    + spin_lock_irqsave(&ch->ch_lock, lock_flags);
    + jsm_check_queue_flow_control(ch);
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    + }
    +
    + /*
    + * This is a special flag. It indicates that at least 1
    + * RX error (parity, framing, or break) has happened.
    + * Mark this in our struct, which will tell me that I have
    + *to do the special RX+LSR read for this FIFO load.
    + */
    + if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
    + jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
    + "%s:%d Port: %d Got an RX error, need to parse LSR\n",
    + __FILE__, __LINE__, port);
    +
    + /*
    + * The next 3 tests should *NOT* happen, as the above test
    + * should encapsulate all 3... At least, thats what Exar says.
    + */
    +
    + if (linestatus & UART_LSR_PE) {
    + ch->ch_err_parity++;
    + jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
    + "%s:%d Port: %d. PAR ERR!\n", __FILE__, __LINE__, port);
    + }
    +
    + if (linestatus & UART_LSR_FE) {
    + ch->ch_err_frame++;
    + jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
    + "%s:%d Port: %d. FRM ERR!\n", __FILE__, __LINE__, port);
    + }
    +
    + if (linestatus & UART_LSR_BI) {
    + ch->ch_err_break++;
    + jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
    + "%s:%d Port: %d. BRK INTR!\n", __FILE__, __LINE__, port);
    + }
    +
    + if (linestatus & UART_LSR_OE) {
    + /*
    + * Rx Oruns. Exar says that an orun will NOT corrupt
    + * the FIFO. It will just replace the holding register
    + * with this new data byte. So basically just ignore this.
    + * Probably we should eventually have an orun stat in our driver...
    + */
    + ch->ch_err_overrun++;
    + jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
    + "%s:%d Port: %d. Rx Overrun!\n", __FILE__, __LINE__, port);
    + }
    +
    + if (linestatus & UART_LSR_THRE) {
    + spin_lock_irqsave(&ch->ch_lock, lock_flags);
    + ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    +
    + /* Transfer data (if any) from Write Queue -> UART. */
    + neo_copy_data_from_queue_to_uart(ch);
    + }
    + else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
    + spin_lock_irqsave(&ch->ch_lock, lock_flags);
    + ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
    +
    + /* Transfer data (if any) from Write Queue -> UART. */
    + neo_copy_data_from_queue_to_uart(ch);
    + }
    +}
    +
    +/*
    + * neo_param()
    + * Send any/all changes to the line to the UART.
    + */
    +static void neo_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;
    +
    + 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)) == 0) {
    + ch->ch_r_head = ch->ch_r_tail = 0;
    + ch->ch_e_head = ch->ch_e_tail = 0;
    + ch->ch_w_head = ch->ch_w_tail = 0;
    +
    + neo_flush_uart_write(ch);
    + neo_flush_uart_read(ch);
    +
    + ch->ch_flags |= (CH_BAUD0);
    + ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
    + neo_assert_modem_signals(ch);
    + ch->ch_old_baud = 0;
    + return;
    +
    + } else if (ch->ch_custom_speed) {
    + baud = ch->ch_custom_speed;
    + if (ch->ch_flags & CH_BAUD0)
    + ch->ch_flags &= ~(CH_BAUD0);
    + } else {
    + int iindex = 0;
    + int jindex = 0;
    +
    + const u64 bauds[4][16] = {
    + {
    + 0, 50, 75, 110,
    + 134, 150, 200, 300,
    + 600, 1200, 1800, 2400,
    + 4800, 9600, 19200, 38400 },
    + {
    + 0, 57600, 115200, 230400,
    + 460800, 150, 200, 921600,
    + 600, 1200, 1800, 2400,
    + 4800, 9600, 19200, 38400 },
    + {
    + 0, 57600, 76800, 115200,
    + 131657, 153600, 230400, 460800,
    + 921600, 1200, 1800, 2400,
    + 4800, 9600, 19200, 38400 },
    + {
    + 0, 57600, 115200, 230400,
    + 460800, 150, 200, 921600,
    + 600, 1200, 1800, 2400,
    + 4800, 9600, 19200, 38400 }
    + };
    +
    + baud = C_BAUD(ch->uart_port.info->tty) & 0xff;
    +
    + if (ch->ch_c_cflag & CBAUDEX)
    + iindex = 1;
    +
    + jindex = baud;
    +
    + if ((iindex >= 0) && (iindex < 4) && (jindex >= 0) && (jindex < 16))
    + baud = bauds[iindex][jindex];
    + else {
    + jsm_printk(IOCTL, DEBUG, &ch->ch_bd->pci_dev,
    + "baud indices were out of range (%d)(%d)",
    + iindex, jindex);
    + baud = 0;
    + }
    +
    + if (baud == 0)
    + baud = 9600;
    +
    + 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;
    +
    + /*
    + * 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;
    + }
    +
    + ier = readb(&ch->ch_neo_uart->ier);
    + uart_lcr = readb(&ch->ch_neo_uart->lcr);
    +
    + if (baud == 0)
    + baud = 9600;
    +
    + quot = ch->ch_bd->bd_dividend / baud;
    +
    + if (quot != 0) {
    + ch->ch_old_baud = baud;
    + writeb(UART_LCR_DLAB, &ch->ch_neo_uart->lcr);
    + writeb((quot & 0xff), &ch->ch_neo_uart->txrx);
    + writeb((quot >> 8), &ch->ch_neo_uart->ier);
    + writeb(lcr, &ch->ch_neo_uart->lcr);
    + }
    +
    + if (uart_lcr != lcr)
    + writeb(lcr, &ch->ch_neo_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_neo_uart->ier);
    +
    + /* Set new start/stop chars */
    + neo_set_new_start_stop_chars(ch);
    +
    + if (ch->ch_c_cflag & CRTSCTS)
    + neo_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))
    + neo_set_no_output_flow_control(ch);
    + else
    + neo_set_ixon_flow_control(ch);
    + }
    + else
    + neo_set_no_output_flow_control(ch);
    +
    + if (ch->ch_c_cflag & CRTSCTS)
    + neo_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))
    + neo_set_no_input_flow_control(ch);
    + else
    + neo_set_ixoff_flow_control(ch);
    + }
    + else
    + neo_set_no_input_flow_control(ch);
    + /*
    + * Adjust the RX FIFO Trigger level if baud is less than 9600.
    + * Not exactly elegant, but this is needed because of the Exar chip's
    + * delay on firing off the RX FIFO interrupt on slower baud rates.
    + */
    + if (baud < 9600) {
    + writeb(1, &ch->ch_neo_uart->rfifo);
    + ch->ch_r_tlevel = 1;
    + }
    +
    + neo_assert_modem_signals(ch);
    +
    + /* Get current status of the modem signals now */
    + neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
    + return;
    +}
    +
    +/*
    + * jsm_neo_intr()
    + *
    + * Neo specific interrupt handler.
    + */
    +static irqreturn_t neo_intr(int irq, void *voidbrd, struct pt_regs *regs)
    +{
    + struct jsm_board *brd = (struct jsm_board *) voidbrd;
    + struct jsm_channel *ch;
    + int port = 0;
    + int type = 0;
    + int current_port;
    + u32 tmp;
    + u32 uart_poll;
    + unsigned long lock_flags;
    + unsigned long lock_flags2;
    + int outofloop_count = 0;
    +
    + brd->intr_count++;
    +
    + /* Lock out the slow poller from running on this board. */
    + spin_lock_irqsave(&brd->bd_intr_lock, lock_flags);
    +
    + /*
    + * Read in "extended" IRQ information from the 32bit Neo register.
    + * Bits 0-7: What port triggered the interrupt.
    + * Bits 8-31: Each 3bits indicate what type of interrupt occurred.
    + */
    + uart_poll = readl(brd->re_map_membase + UART_17158_POLL_ADDR_OFFSET);
    +
    + jsm_printk(INTR, INFO, &brd->pci_dev,
    + "%s:%d uart_poll: %x\n", __FILE__, __LINE__, uart_poll);
    +
    + if (!uart_poll) {
    + jsm_printk(INTR, INFO, &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... */
    +
    + current_port = 0;
    +
    + /* Loop on each port */
    + while (((uart_poll & 0xff) != 0) && (outofloop_count < 0xff)){
    +
    + tmp = uart_poll;
    + outofloop_count++;
    +
    + /* Check current port to see if it has interrupt pending */
    + if ((tmp & jsm_offset_table[current_port]) != 0) {
    + port = current_port;
    + type = tmp >> (8 + (port * 3));
    + type &= 0x7;
    + } else {
    + current_port++;
    + continue;
    + }
    +
    + jsm_printk(INTR, INFO, &brd->pci_dev,
    + "%s:%d port: %x type: %x\n", __FILE__, __LINE__, port, type);
    +
    + /* Remove this port + type from uart_poll */
    + uart_poll &= ~(jsm_offset_table[port]);
    +
    + if (!type) {
    + /* If no type, just ignore it, and move onto next port */
    + jsm_printk(INTR, ERR, &brd->pci_dev,
    + "Interrupt with no type! port: %d\n", port);
    + continue;
    + }
    +
    + /* Switch on type of interrupt we have */
    + switch (type) {
    +
    + case UART_17158_RXRDY_TIMEOUT:
    + /*
    + * RXRDY Time-out is cleared by reading data in the
    + * RX FIFO until it falls below the trigger level.
    + */
    +
    + /* Verify the port is in range. */
    + if (port > brd->nasync)
    + continue;
    +
    + ch = brd->channels[port];
    + neo_copy_data_from_uart_to_queue(ch);
    +
    + /* Call our tty layer to enforce queue flow control if needed. */
    + spin_lock_irqsave(&ch->ch_lock, lock_flags2);
    + jsm_check_queue_flow_control(ch);
    + spin_unlock_irqrestore(&ch->ch_lock, lock_flags2);
    +
    + continue;
    +
    + case UART_17158_RX_LINE_STATUS:
    + /*
    + * RXRDY and RX LINE Status (logic OR of LSR[4:1])
    + */
    + neo_parse_lsr(brd, port);
    + continue;
    +
    + case UART_17158_TXRDY:
    + /*
    + * TXRDY interrupt clears after reading ISR register for the UART channel.
    + */
    +
    + /*
    + * Yes, this is odd...
    + * Why would I check EVERY possibility of type of
    + * interrupt, when we know its TXRDY???
    + * Becuz for some reason, even tho we got triggered for TXRDY,
    + * it seems to be occassionally wrong. Instead of TX, which
    + * it should be, I was getting things like RXDY too. Weird.
    + */
    + neo_parse_isr(brd, port);
    + continue;
    +
    + case UART_17158_MSR:
    + /*
    + * MSR or flow control was seen.
    + */
    + neo_parse_isr(brd, port);
    + continue;
    +
    + default:
    + /*
    + * The UART triggered us with a bogus interrupt type.
    + * It appears the Exar chip, when REALLY bogged down, will throw
    + * these once and awhile.
    + * Its harmless, just ignore it and move on.
    + */
    + jsm_printk(INTR, ERR, &brd->pci_dev,
    + "%s:%d Unknown Interrupt type: %x\n", __FILE__, __LINE__, type);
    + continue;
    + }
    + }
    +
    + spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
    +
    + jsm_printk(INTR, INFO, &brd->pci_dev, "finish.\n");
    + return IRQ_HANDLED;
    +}
    +
    +/*
    + * Neo specific way of turning off the receiver.
    + * Used as a way to enforce queue flow control when in
    + * hardware flow control mode.
    + */
    +static void neo_disable_receiver(struct jsm_channel *ch)
    +{
    + u8 tmp = readb(&ch->ch_neo_uart->ier);
    + tmp &= ~(UART_IER_RDI);
    + writeb(tmp, &ch->ch_neo_uart->ier);
    +}
    +
    +
    +/*
    + * Neo specific way of turning on the receiver.
    + * Used as a way to un-enforce queue flow control when in
    + * hardware flow control mode.
    + */
    +static void neo_enable_receiver(struct jsm_channel *ch)
    +{
    + u8 tmp = readb(&ch->ch_neo_uart->ier);
    + tmp |= (UART_IER_RDI);
    + writeb(tmp, &ch->ch_neo_uart->ier);
    +}
    +
    +static void neo_send_start_character(struct jsm_channel *ch)
    +{
    + unsigned char xdata;
    + if (!ch)
    + return;
    +
    + if (ch->ch_startc != __DISABLED_CHAR) {
    + ch->ch_xon_sends++;
    + writeb(ch->ch_startc, &ch->ch_neo_uart->txrx);
    +
    + /* flush write operation */
    + xdata = readb(&ch->ch_neo_uart->txrx);
    + }
    +}
    +
    +static void neo_send_stop_character(struct jsm_channel *ch)
    +{
    + unsigned char xdata;
    +
    + if (!ch)
    + return;
    +
    + if (ch->ch_stopc != __DISABLED_CHAR) {
    + ch->ch_xoff_sends++;
    + writeb(ch->ch_stopc, &ch->ch_neo_uart->txrx);
    +
    + /* flush write operation */
    + xdata = readb(&ch->ch_neo_uart->txrx);
    + }
    +}
    +
    +/*
    + * neo_uart_init
    + */
    +static void neo_uart_init(struct jsm_channel *ch)
    +{
    + writeb(0, &ch->ch_neo_uart->ier);
    + writeb(0, &ch->ch_neo_uart->efr);
    + writeb(UART_EFR_ECB, &ch->ch_neo_uart->efr);
    +
    + /* Clear out UART and FIFO */
    + readb(&ch->ch_neo_uart->txrx);
    + writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
    + readb(&ch->ch_neo_uart->lsr);
    + readb(&ch->ch_neo_uart->msr);
    +
    + ch->ch_flags |= CH_FIFO_ENABLED;
    +
    + /* Assert any signals we want up */
    + writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
    +}
    +
    +/*
    + * Make the UART completely turn off.
    + */
    +static void neo_uart_off(struct jsm_channel *ch)
    +{
    + /* Turn off UART enhanced bits */
    + writeb(0, &ch->ch_neo_uart->efr);
    +
    + /* Stop all interrupts from occurring. */
    + writeb(0, &ch->ch_neo_uart->ier);
    +}
    +
    +static u32 neo_get_uart_bytes_left(struct jsm_channel *ch)
    +{
    + u8 left = 0;
    + u8 lsr = readb(&ch->ch_neo_uart->lsr);
    +
    + /* We must cache the LSR as some of the bits get reset once read... */
    + ch->ch_cached_lsr |= lsr;
    +
    + /* Determine whether the Transmitter is empty or not */
    + if (!(lsr & UART_LSR_TEMT))
    + left = 1;
    + else {
    + ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
    + left = 0;
    + }
    +
    + return left;
    +}
    +
    +/* Channel lock MUST be held by the calling function! */
    +static void neo_send_break(struct jsm_channel *ch)
    +{
    + /*
    + * 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.
    + */
    +
    + /* Tell the UART to start sending the break */
    + if (!(ch->ch_flags & CH_BREAK_SENDING)) {
    + u8 temp = readb(&ch->ch_neo_uart->lcr);
    + writeb((temp | UART_LCR_SBC), &ch->ch_neo_uart->lcr);
    + ch->ch_flags |= (CH_BREAK_SENDING);
    + }
    +}
    +
    +/*
    + * neo_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 neo_send_immediate_char(struct jsm_channel *ch, unsigned char c)
    +{
    + if (!ch)
    + return;
    +
    + writeb(c, &ch->ch_neo_uart->txrx);
    +}
    +
    +struct board_ops jsm_neo_ops = {
    + .intr = neo_intr,
    + .uart_init = neo_uart_init,
    + .uart_off = neo_uart_off,
    + .param = neo_param,
    + .assert_modem_signals = neo_assert_modem_signals,
    + .flush_uart_write = neo_flush_uart_write,
    + .flush_uart_read = neo_flush_uart_read,
    + .disable_receiver = neo_disable_receiver,
    + .enable_receiver = neo_enable_receiver,
    + .send_break = neo_send_break,
    + .clear_break = neo_clear_break,
    + .send_start_character = neo_send_start_character,
    + .send_stop_character = neo_send_stop_character,
    + .copy_data_from_queue_to_uart = neo_copy_data_from_queue_to_uart,
    + .get_uart_bytes_left = neo_get_uart_bytes_left,
    + .send_immediate_char = neo_send_immediate_char
    +};
    \
     
     \ /
      Last update: 2005-03-22 14:11    [W:2.704 / U:0.040 seconds]
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