--- /dev/null
+/*
+ * 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.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *
+ * 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, int force)
+{
+ 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 = 0;
+ 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;
+
+ /* Get our cached LSR */
+ linestatus = ch->ch_cached_lsr;
+ 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) {
+ u8 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);
+}
+
+static void cls_copy_data_from_queue_to_uart(struct jsm_channel *ch)
+{
+ u16 tail;
+ int n;
+ int qlen;
+ u32 len_written = 0;
+ struct circ_buf *circ;
+
+ if (!ch)
+ return;
+
+ circ = &ch->uart_port.state->xmit;
+
+ /* No data to write to the UART */
+ if (uart_circ_empty(circ))
+ 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;
+
+ /* 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;
+
+ /* cache tail of queue */
+ tail = circ->tail & (UART_XMIT_SIZE - 1);
+ qlen = uart_circ_chars_pending(circ);
+
+ /* Find minimum of the FIFO space, versus queue length */
+ n = min(n, qlen);
+
+ while (n > 0) {
+ writeb(circ->buf[tail], &ch->ch_cls_uart->txrx);
+ tail = (tail + 1) & (UART_XMIT_SIZE - 1);
+ n--;
+ ch->ch_txcount++;
+ len_written++;
+ }
+
+ /* Update the final tail */
+ circ->tail = tail & (UART_XMIT_SIZE - 1);
+
+ if (len_written > ch->ch_t_tlevel)
+ ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
+
+ if (uart_circ_empty(circ))
+ 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)) == 0) {
+ 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;
+
+ /*
+ * 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_cls_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) {
+ 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_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 u32 cls_get_uart_bytes_left(struct jsm_channel *ch)
+{
+ u8 left = 0;
+ u8 lsr = readb(&ch->ch_cls_uart->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;
+}
+
+/*
+ * 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);
+ }
+}
+
+/*
+ * 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 jsm_channel *ch, unsigned char c)
+{
+ writeb(c, &ch->ch_cls_uart->txrx);
+}
+
+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,
+ .get_uart_bytes_left = cls_get_uart_bytes_left,
+ .send_immediate_char = cls_send_immediate_char
+};
+
projects / platform / kernel / linux-rpi.git / commitdiff