1 // SPDX-License-Identifier: GPL-2.0+
2 /************************************************************************
3 * Copyright 2003 Digi International (www.digi.com)
5 * Copyright (C) 2004 IBM Corporation. All rights reserved.
8 * Scott H Kilau <Scott_Kilau@digi.com>
9 * Ananda Venkatarman <mansarov@us.ibm.com>
11 * 01/19/06: changed jsm_input routine to use the dynamically allocated
12 * tty_buffer changes. Contributors: Scott Kilau and Ananda V.
13 ***********************************************************************/
14 #include <linux/tty.h>
15 #include <linux/tty_flip.h>
16 #include <linux/serial_reg.h>
17 #include <linux/delay.h> /* For udelay */
18 #include <linux/pci.h>
19 #include <linux/slab.h>
23 static DECLARE_BITMAP(linemap, MAXLINES);
25 static void jsm_carrier(struct jsm_channel *ch);
27 static inline int jsm_get_mstat(struct jsm_channel *ch)
32 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "start\n");
34 mstat = (ch->ch_mostat | ch->ch_mistat);
38 if (mstat & UART_MCR_DTR)
40 if (mstat & UART_MCR_RTS)
42 if (mstat & UART_MSR_CTS)
44 if (mstat & UART_MSR_DSR)
46 if (mstat & UART_MSR_RI)
48 if (mstat & UART_MSR_DCD)
51 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
55 static unsigned int jsm_tty_tx_empty(struct uart_port *port)
61 * Return modem signals to ld.
63 static unsigned int jsm_tty_get_mctrl(struct uart_port *port)
66 struct jsm_channel *channel =
67 container_of(port, struct jsm_channel, uart_port);
69 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
71 result = jsm_get_mstat(channel);
76 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
82 * jsm_set_modem_info()
84 * Set modem signals, called by ld.
86 static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl)
88 struct jsm_channel *channel =
89 container_of(port, struct jsm_channel, uart_port);
91 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
93 if (mctrl & TIOCM_RTS)
94 channel->ch_mostat |= UART_MCR_RTS;
96 channel->ch_mostat &= ~UART_MCR_RTS;
98 if (mctrl & TIOCM_DTR)
99 channel->ch_mostat |= UART_MCR_DTR;
101 channel->ch_mostat &= ~UART_MCR_DTR;
103 channel->ch_bd->bd_ops->assert_modem_signals(channel);
105 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
112 * Take data from the user or kernel and send it out to the FEP.
113 * In here exists all the Transparent Print magic as well.
115 static void jsm_tty_write(struct uart_port *port)
117 struct jsm_channel *channel;
119 channel = container_of(port, struct jsm_channel, uart_port);
120 channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel);
123 static void jsm_tty_start_tx(struct uart_port *port)
125 struct jsm_channel *channel =
126 container_of(port, struct jsm_channel, uart_port);
128 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
130 channel->ch_flags &= ~(CH_STOP);
133 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
136 static void jsm_tty_stop_tx(struct uart_port *port)
138 struct jsm_channel *channel =
139 container_of(port, struct jsm_channel, uart_port);
141 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n");
143 channel->ch_flags |= (CH_STOP);
145 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n");
148 static void jsm_tty_send_xchar(struct uart_port *port, char ch)
150 unsigned long lock_flags;
151 struct jsm_channel *channel =
152 container_of(port, struct jsm_channel, uart_port);
153 struct ktermios *termios;
155 spin_lock_irqsave(&port->lock, lock_flags);
156 termios = &port->state->port.tty->termios;
157 if (ch == termios->c_cc[VSTART])
158 channel->ch_bd->bd_ops->send_start_character(channel);
160 if (ch == termios->c_cc[VSTOP])
161 channel->ch_bd->bd_ops->send_stop_character(channel);
162 spin_unlock_irqrestore(&port->lock, lock_flags);
165 static void jsm_tty_stop_rx(struct uart_port *port)
167 struct jsm_channel *channel =
168 container_of(port, struct jsm_channel, uart_port);
170 channel->ch_bd->bd_ops->disable_receiver(channel);
173 static void jsm_tty_break(struct uart_port *port, int break_state)
175 unsigned long lock_flags;
176 struct jsm_channel *channel =
177 container_of(port, struct jsm_channel, uart_port);
179 spin_lock_irqsave(&port->lock, lock_flags);
180 if (break_state == -1)
181 channel->ch_bd->bd_ops->send_break(channel);
183 channel->ch_bd->bd_ops->clear_break(channel);
185 spin_unlock_irqrestore(&port->lock, lock_flags);
188 static int jsm_tty_open(struct uart_port *port)
190 struct jsm_board *brd;
191 struct jsm_channel *channel =
192 container_of(port, struct jsm_channel, uart_port);
193 struct ktermios *termios;
195 /* Get board pointer from our array of majors we have allocated */
196 brd = channel->ch_bd;
199 * Allocate channel buffers for read/write/error.
200 * Set flag, so we don't get trounced on.
202 channel->ch_flags |= (CH_OPENING);
204 /* Drop locks, as malloc with GFP_KERNEL can sleep */
206 if (!channel->ch_rqueue) {
207 channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL);
208 if (!channel->ch_rqueue) {
209 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
210 "unable to allocate read queue buf\n");
214 if (!channel->ch_equeue) {
215 channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL);
216 if (!channel->ch_equeue) {
217 jsm_dbg(INIT, &channel->ch_bd->pci_dev,
218 "unable to allocate error queue buf\n");
223 channel->ch_flags &= ~(CH_OPENING);
225 * Initialize if neither terminal is open.
227 jsm_dbg(OPEN, &channel->ch_bd->pci_dev,
228 "jsm_open: initializing channel in open...\n");
231 * Flush input queues.
233 channel->ch_r_head = channel->ch_r_tail = 0;
234 channel->ch_e_head = channel->ch_e_tail = 0;
236 brd->bd_ops->flush_uart_write(channel);
237 brd->bd_ops->flush_uart_read(channel);
239 channel->ch_flags = 0;
240 channel->ch_cached_lsr = 0;
241 channel->ch_stops_sent = 0;
243 termios = &port->state->port.tty->termios;
244 channel->ch_c_cflag = termios->c_cflag;
245 channel->ch_c_iflag = termios->c_iflag;
246 channel->ch_c_oflag = termios->c_oflag;
247 channel->ch_c_lflag = termios->c_lflag;
248 channel->ch_startc = termios->c_cc[VSTART];
249 channel->ch_stopc = termios->c_cc[VSTOP];
251 /* Tell UART to init itself */
252 brd->bd_ops->uart_init(channel);
255 * Run param in case we changed anything
257 brd->bd_ops->param(channel);
259 jsm_carrier(channel);
261 channel->ch_open_count++;
263 jsm_dbg(OPEN, &channel->ch_bd->pci_dev, "finish\n");
267 static void jsm_tty_close(struct uart_port *port)
269 struct jsm_board *bd;
270 struct jsm_channel *channel =
271 container_of(port, struct jsm_channel, uart_port);
273 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "start\n");
277 channel->ch_flags &= ~(CH_STOPI);
279 channel->ch_open_count--;
282 * If we have HUPCL set, lower DTR and RTS
284 if (channel->ch_c_cflag & HUPCL) {
285 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev,
286 "Close. HUPCL set, dropping DTR/RTS\n");
289 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
290 bd->bd_ops->assert_modem_signals(channel);
293 /* Turn off UART interrupts for this port */
294 channel->ch_bd->bd_ops->uart_off(channel);
296 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "finish\n");
299 static void jsm_tty_set_termios(struct uart_port *port,
300 struct ktermios *termios,
301 struct ktermios *old_termios)
303 unsigned long lock_flags;
304 struct jsm_channel *channel =
305 container_of(port, struct jsm_channel, uart_port);
307 spin_lock_irqsave(&port->lock, lock_flags);
308 channel->ch_c_cflag = termios->c_cflag;
309 channel->ch_c_iflag = termios->c_iflag;
310 channel->ch_c_oflag = termios->c_oflag;
311 channel->ch_c_lflag = termios->c_lflag;
312 channel->ch_startc = termios->c_cc[VSTART];
313 channel->ch_stopc = termios->c_cc[VSTOP];
315 channel->ch_bd->bd_ops->param(channel);
316 jsm_carrier(channel);
317 spin_unlock_irqrestore(&port->lock, lock_flags);
320 static const char *jsm_tty_type(struct uart_port *port)
325 static void jsm_tty_release_port(struct uart_port *port)
329 static int jsm_tty_request_port(struct uart_port *port)
334 static void jsm_config_port(struct uart_port *port, int flags)
336 port->type = PORT_JSM;
339 static const struct uart_ops jsm_ops = {
340 .tx_empty = jsm_tty_tx_empty,
341 .set_mctrl = jsm_tty_set_mctrl,
342 .get_mctrl = jsm_tty_get_mctrl,
343 .stop_tx = jsm_tty_stop_tx,
344 .start_tx = jsm_tty_start_tx,
345 .send_xchar = jsm_tty_send_xchar,
346 .stop_rx = jsm_tty_stop_rx,
347 .break_ctl = jsm_tty_break,
348 .startup = jsm_tty_open,
349 .shutdown = jsm_tty_close,
350 .set_termios = jsm_tty_set_termios,
351 .type = jsm_tty_type,
352 .release_port = jsm_tty_release_port,
353 .request_port = jsm_tty_request_port,
354 .config_port = jsm_config_port,
360 * Init the tty subsystem. Called once per board after board has been
361 * downloaded and init'ed.
363 int jsm_tty_init(struct jsm_board *brd)
367 struct jsm_channel *ch;
372 jsm_dbg(INIT, &brd->pci_dev, "start\n");
375 * Initialize board structure elements.
378 brd->nasync = brd->maxports;
381 * Allocate channel memory that might not have been allocated
382 * when the driver was first loaded.
384 for (i = 0; i < brd->nasync; i++) {
385 if (!brd->channels[i]) {
388 * Okay to malloc with GFP_KERNEL, we are not at
389 * interrupt context, and there are no locks held.
391 brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL);
392 if (!brd->channels[i]) {
393 jsm_dbg(CORE, &brd->pci_dev,
394 "%s:%d Unable to allocate memory for channel struct\n",
400 ch = brd->channels[0];
401 vaddr = brd->re_map_membase;
403 /* Set up channel variables */
404 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
406 if (!brd->channels[i])
409 spin_lock_init(&ch->ch_lock);
411 if (brd->bd_uart_offset == 0x200)
412 ch->ch_neo_uart = vaddr + (brd->bd_uart_offset * i);
414 ch->ch_cls_uart = vaddr + (brd->bd_uart_offset * i);
419 /* .25 second delay */
420 ch->ch_close_delay = 250;
422 init_waitqueue_head(&ch->ch_flags_wait);
425 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
429 int jsm_uart_port_init(struct jsm_board *brd)
437 jsm_dbg(INIT, &brd->pci_dev, "start\n");
440 * Initialize board structure elements.
443 brd->nasync = brd->maxports;
445 /* Set up channel variables */
446 for (i = 0; i < brd->nasync; i++) {
448 if (!brd->channels[i])
451 brd->channels[i]->uart_port.irq = brd->irq;
452 brd->channels[i]->uart_port.uartclk = 14745600;
453 brd->channels[i]->uart_port.type = PORT_JSM;
454 brd->channels[i]->uart_port.iotype = UPIO_MEM;
455 brd->channels[i]->uart_port.membase = brd->re_map_membase;
456 brd->channels[i]->uart_port.fifosize = 16;
457 brd->channels[i]->uart_port.ops = &jsm_ops;
458 line = find_first_zero_bit(linemap, MAXLINES);
459 if (line >= MAXLINES) {
460 printk(KERN_INFO "jsm: linemap is full, added device failed\n");
463 set_bit(line, linemap);
464 brd->channels[i]->uart_port.line = line;
465 rc = uart_add_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
467 printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i);
470 printk(KERN_INFO "jsm: Port %d added\n", i);
473 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
477 int jsm_remove_uart_port(struct jsm_board *brd)
480 struct jsm_channel *ch;
485 jsm_dbg(INIT, &brd->pci_dev, "start\n");
488 * Initialize board structure elements.
491 brd->nasync = brd->maxports;
493 /* Set up channel variables */
494 for (i = 0; i < brd->nasync; i++) {
496 if (!brd->channels[i])
499 ch = brd->channels[i];
501 clear_bit(ch->uart_port.line, linemap);
502 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
505 jsm_dbg(INIT, &brd->pci_dev, "finish\n");
509 void jsm_input(struct jsm_channel *ch)
511 struct jsm_board *bd;
512 struct tty_struct *tp;
513 struct tty_port *port;
518 unsigned long lock_flags;
523 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
525 port = &ch->uart_port.state->port;
532 spin_lock_irqsave(&ch->ch_lock, lock_flags);
535 *Figure the number of characters in the buffer.
536 *Exit immediately if none.
541 head = ch->ch_r_head & rmask;
542 tail = ch->ch_r_tail & rmask;
544 data_len = (head - tail) & rmask;
546 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
550 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n");
553 *If the device is not open, or CREAD is off, flush
554 *input data and return immediately.
556 if (!tp || !C_CREAD(tp)) {
558 jsm_dbg(READ, &ch->ch_bd->pci_dev,
559 "input. dropping %d bytes on port %d...\n",
560 data_len, ch->ch_portnum);
561 ch->ch_r_head = tail;
563 /* Force queue flow control to be released, if needed */
564 jsm_check_queue_flow_control(ch);
566 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
571 * If we are throttled, simply don't read any data.
573 if (ch->ch_flags & CH_STOPI) {
574 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
575 jsm_dbg(READ, &ch->ch_bd->pci_dev,
576 "Port %d throttled, not reading any data. head: %x tail: %x\n",
577 ch->ch_portnum, head, tail);
581 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start 2\n");
583 len = tty_buffer_request_room(port, data_len);
586 * len now contains the most amount of data we can copy,
587 * bounded either by the flip buffer size or the amount
588 * of data the card actually has pending...
591 s = ((head >= tail) ? head : RQUEUESIZE) - tail;
598 * If conditions are such that ld needs to see all
599 * UART errors, we will have to walk each character
600 * and error byte and send them to the buffer one at
604 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
605 for (i = 0; i < s; i++) {
607 * Give the Linux ld the flags in the
610 if (*(ch->ch_equeue +tail +i) & UART_LSR_BI)
611 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_BREAK);
612 else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE)
613 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_PARITY);
614 else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE)
615 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_FRAME);
617 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_NORMAL);
620 tty_insert_flip_string(port, ch->ch_rqueue + tail, s);
624 /* Flip queue if needed */
628 ch->ch_r_tail = tail & rmask;
629 ch->ch_e_tail = tail & rmask;
630 jsm_check_queue_flow_control(ch);
631 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
633 /* Tell the tty layer its okay to "eat" the data now */
634 tty_flip_buffer_push(port);
636 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n");
639 static void jsm_carrier(struct jsm_channel *ch)
641 struct jsm_board *bd;
643 int virt_carrier = 0;
644 int phys_carrier = 0;
646 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "start\n");
652 if (ch->ch_mistat & UART_MSR_DCD) {
653 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "mistat: %x D_CD: %x\n",
654 ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
658 if (ch->ch_c_cflag & CLOCAL)
661 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "DCD: physical: %d virt: %d\n",
662 phys_carrier, virt_carrier);
665 * Test for a VIRTUAL carrier transition to HIGH.
667 if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
670 * When carrier rises, wake any threads waiting
671 * for carrier in the open routine.
674 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "carrier: virt DCD rose\n");
676 if (waitqueue_active(&(ch->ch_flags_wait)))
677 wake_up_interruptible(&ch->ch_flags_wait);
681 * Test for a PHYSICAL carrier transition to HIGH.
683 if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
686 * When carrier rises, wake any threads waiting
687 * for carrier in the open routine.
690 jsm_dbg(CARR, &ch->ch_bd->pci_dev,
691 "carrier: physical DCD rose\n");
693 if (waitqueue_active(&(ch->ch_flags_wait)))
694 wake_up_interruptible(&ch->ch_flags_wait);
698 * Test for a PHYSICAL transition to low, so long as we aren't
699 * currently ignoring physical transitions (which is what "virtual
700 * carrier" indicates).
702 * The transition of the virtual carrier to low really doesn't
703 * matter... it really only means "ignore carrier state", not
704 * "make pretend that carrier is there".
706 if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
707 && (phys_carrier == 0)) {
709 * When carrier drops:
711 * Drop carrier on all open units.
713 * Flush queues, waking up any task waiting in the
716 * Send a hangup to the control terminal.
718 * Enable all select calls.
720 if (waitqueue_active(&(ch->ch_flags_wait)))
721 wake_up_interruptible(&ch->ch_flags_wait);
725 * Make sure that our cached values reflect the current reality.
727 if (virt_carrier == 1)
728 ch->ch_flags |= CH_FCAR;
730 ch->ch_flags &= ~CH_FCAR;
732 if (phys_carrier == 1)
733 ch->ch_flags |= CH_CD;
735 ch->ch_flags &= ~CH_CD;
739 void jsm_check_queue_flow_control(struct jsm_channel *ch)
741 struct board_ops *bd_ops = ch->ch_bd->bd_ops;
744 /* Store how much space we have left in the queue */
745 if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0)
746 qleft += RQUEUEMASK + 1;
749 * Check to see if we should enforce flow control on our queue because
750 * the ld (or user) isn't reading data out of our queue fast enuf.
752 * NOTE: This is done based on what the current flow control of the
755 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
756 * This will cause the UART's FIFO to back up, and force
757 * the RTS signal to be dropped.
758 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
759 * the other side, in hopes it will stop sending data to us.
760 * 3) NONE - Nothing we can do. We will simply drop any extra data
761 * that gets sent into us when the queue fills up.
765 if (ch->ch_c_cflag & CRTSCTS) {
766 if (!(ch->ch_flags & CH_RECEIVER_OFF)) {
767 bd_ops->disable_receiver(ch);
768 ch->ch_flags |= (CH_RECEIVER_OFF);
769 jsm_dbg(READ, &ch->ch_bd->pci_dev,
770 "Internal queue hit hilevel mark (%d)! Turning off interrupts\n",
775 else if (ch->ch_c_iflag & IXOFF) {
776 if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
777 bd_ops->send_stop_character(ch);
779 jsm_dbg(READ, &ch->ch_bd->pci_dev,
780 "Sending stop char! Times sent: %x\n",
787 * Check to see if we should unenforce flow control because
788 * ld (or user) finally read enuf data out of our queue.
790 * NOTE: This is done based on what the current flow control of the
793 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
794 * This will cause the UART's FIFO to raise RTS back up,
795 * which will allow the other side to start sending data again.
796 * 2) SWFLOW (IXOFF) - Send a start character to
797 * the other side, so it will start sending data to us again.
798 * 3) NONE - Do nothing. Since we didn't do anything to turn off the
799 * other side, we don't need to do anything now.
801 if (qleft > (RQUEUESIZE / 2)) {
803 if (ch->ch_c_cflag & CRTSCTS) {
804 if (ch->ch_flags & CH_RECEIVER_OFF) {
805 bd_ops->enable_receiver(ch);
806 ch->ch_flags &= ~(CH_RECEIVER_OFF);
807 jsm_dbg(READ, &ch->ch_bd->pci_dev,
808 "Internal queue hit lowlevel mark (%d)! Turning on interrupts\n",
813 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
814 ch->ch_stops_sent = 0;
815 bd_ops->send_start_character(ch);
816 jsm_dbg(READ, &ch->ch_bd->pci_dev,
817 "Sending start char!\n");