// SPDX-License-Identifier: GPL-2.0
/*
* 3215 line mode terminal driver.
*
* Copyright IBM Corp. 1999, 2009
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*
* Updated:
* Aug-2000: Added tab support
* Dan Morrison, IBM Corporation <dmorriso@cse.buffalo.edu>
*/
#include <linux/types.h>
#include <linux/kdev_t.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/vt_kern.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/panic_notifier.h>
#include <linux/reboot.h>
#include <linux/serial.h> /* ASYNC_* flags */
#include <linux/slab.h>
#include <asm/ccwdev.h>
#include <asm/cio.h>
#include <linux/io.h>
#include <asm/ebcdic.h>
#include <linux/uaccess.h>
#include <asm/delay.h>
#include <asm/cpcmd.h>
#include <asm/setup.h>
#include "ctrlchar.h"
#define NR_3215 1
#define NR_3215_REQ (4*NR_3215)
#define RAW3215_BUFFER_SIZE 65536 /* output buffer size */
#define RAW3215_INBUF_SIZE 256 /* input buffer size */
#define RAW3215_MIN_SPACE 128 /* minimum free space for wakeup */
#define RAW3215_MIN_WRITE 1024 /* min. length for immediate output */
#define RAW3215_MAX_BYTES 3968 /* max. bytes to write with one ssch */
#define RAW3215_MAX_NEWLINE 50 /* max. lines to write with one ssch */
#define RAW3215_NR_CCWS 3
#define RAW3215_TIMEOUT HZ/10 /* time for delayed output */
#define RAW3215_FIXED 1 /* 3215 console device is not be freed */
#define RAW3215_WORKING 4 /* set if a request is being worked on */
#define RAW3215_THROTTLED 8 /* set if reading is disabled */
#define RAW3215_STOPPED 16 /* set if writing is disabled */
#define RAW3215_TIMER_RUNS 64 /* set if the output delay timer is on */
#define RAW3215_FLUSHING 128 /* set to flush buffer (no delay) */
#define TAB_STOP_SIZE 8 /* tab stop size */
/*
* Request types for a 3215 device
*/
enum raw3215_type {
RAW3215_FREE, RAW3215_READ, RAW3215_WRITE
};
/*
* Request structure for a 3215 device
*/
struct raw3215_req {
enum raw3215_type type; /* type of the request */
int start, len; /* start index & len in output buffer */
int delayable; /* indication to wait for more data */
int residual; /* residual count for read request */
struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */
struct raw3215_info *info; /* pointer to main structure */
struct raw3215_req *next; /* pointer to next request */
} __attribute__ ((aligned(8)));
struct raw3215_info {
struct tty_port port;
struct ccw_device *cdev; /* device for tty driver */
spinlock_t *lock; /* pointer to irq lock */
int flags; /* state flags */
char *buffer; /* pointer to output buffer */
char *inbuf; /* pointer to input buffer */
int head; /* first free byte in output buffer */
int count; /* number of bytes in output buffer */
int written; /* number of bytes in write requests */
struct raw3215_req *queued_read; /* pointer to queued read requests */
struct raw3215_req *queued_write;/* pointer to queued write requests */
wait_queue_head_t empty_wait; /* wait queue for flushing */
struct timer_list timer; /* timer for delayed output */
int line_pos; /* position on the line (for tabs) */
char ubuffer[80]; /* copy_from_user buffer */
};
/* array of 3215 devices structures */
static struct raw3215_info *raw3215[NR_3215];
/* spinlock to protect the raw3215 array */
static DEFINE_SPINLOCK(raw3215_device_lock);
/* list of free request structures */
static struct raw3215_req *raw3215_freelist;
/* spinlock to protect free list */
static DEFINE_SPINLOCK(raw3215_freelist_lock);
static struct tty_driver *tty3215_driver;
static bool con3215_drop = true;
/*
* Get a request structure from the free list
*/
static inline struct raw3215_req *raw3215_alloc_req(void)
{
struct raw3215_req *req;
unsigned long flags;
spin_lock_irqsave(&raw3215_freelist_lock, flags);
req = raw3215_freelist;
raw3215_freelist = req->next;
spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
return req;
}
/*
* Put a request structure back to the free list
*/
static inline void raw3215_free_req(struct raw3215_req *req)
{
unsigned long flags;
if (req->type == RAW3215_FREE)
return; /* don't free a free request */
req->type = RAW3215_FREE;
spin_lock_irqsave(&raw3215_freelist_lock, flags);
req->next = raw3215_freelist;
raw3215_freelist = req;
spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
}
/*
* Set up a read request that reads up to 160 byte from the 3215 device.
* If there is a queued read request it is used, but that shouldn't happen
* because a 3215 terminal won't accept a new read before the old one is
* completed.
*/
static void raw3215_mk_read_req(struct raw3215_info *raw)
{
struct raw3215_req *req;
struct ccw1 *ccw;
/* there can only be ONE read request at a time */
req = raw->queued_read;
if (req == NULL) {
/* no queued read request, use new req structure */
req = raw3215_alloc_req();
req->type = RAW3215_READ;
req->info = raw;
raw->queued_read = req;
}
ccw = req->ccws;
ccw->cmd_code = 0x0A; /* read inquiry */
ccw->flags = 0x20; /* ignore incorrect length */
ccw->count = 160;
ccw->cda = (__u32)__pa(raw->inbuf);
}
/*
* Set up a write request with the information from the main structure.
* A ccw chain is created that writes as much as possible from the output
* buffer to the 3215 device. If a queued write exists it is replaced by
* the new, probably lengthened request.
*/
static void raw3215_mk_write_req(struct raw3215_info *raw)
{
struct raw3215_req *req;
struct ccw1 *ccw;
int len, count, ix, lines;
if (raw->count <= raw->written)
return;
/* check if there is a queued write request */
req = raw->queued_write;
if (req == NULL) {
/* no queued write request, use new req structure */
req = raw3215_alloc_req();
req->type = RAW3215_WRITE;
req->info = raw;
raw->queued_write = req;
} else {
raw->written -= req->len;
}
ccw = req->ccws;
req->start = (raw->head - raw->count + raw->written) &
(RAW3215_BUFFER_SIZE - 1);
/*
* now we have to count newlines. We can at max accept
* RAW3215_MAX_NEWLINE newlines in a single ssch due to
* a restriction in VM
*/
lines = 0;
ix = req->start;
while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) {
if (raw->buffer[ix] == 0x15)
lines++;
ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
}
len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
if (len > RAW3215_MAX_BYTES)
len = RAW3215_MAX_BYTES;
req->len = len;
raw->written += len;
/* set the indication if we should try to enlarge this request */
req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE);
ix = req->start;
while (len > 0) {
if (ccw > req->ccws)
ccw[-1].flags |= 0x40; /* use command chaining */
ccw->cmd_code = 0x01; /* write, auto carrier return */
ccw->flags = 0x20; /* ignore incorrect length ind. */
ccw->cda = (__u32)__pa(raw->buffer + ix);
count = len;
if (ix + count > RAW3215_BUFFER_SIZE)
count = RAW3215_BUFFER_SIZE - ix;
ccw->count = count;
len -= count;
ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1);
ccw++;
}
/*
* Add a NOP to the channel program. 3215 devices are purely
* emulated and its much better to avoid the channel end
* interrupt in this case.
*/
if (ccw > req->ccws)
ccw[-1].flags |= 0x40; /* use command chaining */
ccw->cmd_code = 0x03; /* NOP */
ccw->flags = 0;
ccw->cda = 0;
ccw->count = 1;
}
/*
* Start a read or a write request
*/
static void raw3215_start_io(struct raw3215_info *raw)
{
struct raw3215_req *req;
int res;
req = raw->queued_read;
if (req != NULL &&
!(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) {
/* dequeue request */
raw->queued_read = NULL;
res = ccw_device_start(raw->cdev, req->ccws,
(unsigned long) req, 0, 0);
if (res != 0) {
/* do_IO failed, put request back to queue */
raw->queued_read = req;
} else {
raw->flags |= RAW3215_WORKING;
}
}
req = raw->queued_write;
if (req != NULL &&
!(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) {
/* dequeue request */
raw->queued_write = NULL;
res = ccw_device_start(raw->cdev, req->ccws,
(unsigned long) req, 0, 0);
if (res != 0) {
/* do_IO failed, put request back to queue */
raw->queued_write = req;
} else {
raw->flags |= RAW3215_WORKING;
}
}
}
/*
* Function to start a delayed output after RAW3215_TIMEOUT seconds
*/
static void raw3215_timeout(struct timer_list *t)
{
struct raw3215_info *raw = from_timer(raw, t, timer);
unsigned long flags;
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
raw->flags &= ~RAW3215_TIMER_RUNS;
raw3215_mk_write_req(raw);
raw3215_start_io(raw);
if ((raw->queued_read || raw->queued_write) &&
!(raw->flags & RAW3215_WORKING) &&
!(raw->flags & RAW3215_TIMER_RUNS)) {
raw->timer.expires = RAW3215_TIMEOUT + jiffies;
add_timer(&raw->timer);
raw->flags |= RAW3215_TIMER_RUNS;
}
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
}
/*
* Function to conditionally start an IO. A read is started immediately,
* a write is only started immediately if the flush flag is on or the
* amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
* done immediately a timer is started with a delay of RAW3215_TIMEOUT.
*/
static inline void raw3215_try_io(struct raw3215_info *raw)
{
if (!tty_port_initialized(&raw->port))
return;
if (raw->queued_read != NULL)
raw3215_start_io(raw);
else if (raw->queued_write != NULL) {
if ((raw->queued_write->delayable == 0) ||
(raw->flags & RAW3215_FLUSHING)) {
/* execute write requests bigger than minimum size */
raw3215_start_io(raw);
}
}
if ((raw->queued_read || raw->queued_write) &&
!(raw->flags & RAW3215_WORKING) &&
!(raw->flags & RAW3215_TIMER_RUNS)) {
raw->timer.expires = RAW3215_TIMEOUT + jiffies;
add_timer(&raw->timer);
raw->flags |= RAW3215_TIMER_RUNS;
}
}
/*
* Try to start the next IO and wake up processes waiting on the tty.
*/
static void raw3215_next_io(struct raw3215_info *raw, struct tty_struct *tty)
{
raw3215_mk_write_req(raw);
raw3215_try_io(raw);
if (tty && RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE)
tty_wakeup(tty);
}
/*
* Interrupt routine, called from common io layer
*/
static void raw3215_irq(struct ccw_device *cdev, unsigned long intparm,
struct irb *irb)
{
struct raw3215_info *raw;
struct raw3215_req *req;
struct tty_struct *tty;
int cstat, dstat;
int count;
raw = dev_get_drvdata(&cdev->dev);
req = (struct raw3215_req *) intparm;
tty = tty_port_tty_get(&raw->port);
cstat = irb->scsw.cmd.cstat;
dstat = irb->scsw.cmd.dstat;
if (cstat != 0)
raw3215_next_io(raw, tty);
if (dstat & 0x01) { /* we got a unit exception */
dstat &= ~0x01; /* we can ignore it */
}
switch (dstat) {
case 0x80:
if (cstat != 0)
break;
/* Attention interrupt, someone hit the enter key */
raw3215_mk_read_req(raw);
raw3215_next_io(raw, tty);
break;
case 0x08:
case 0x0C:
/* Channel end interrupt. */
if ((raw = req->info) == NULL)
goto put_tty; /* That shouldn't happen ... */
if (req->type == RAW3215_READ) {
/* store residual count, then wait for device end */
req->residual = irb->scsw.cmd.count;
}
if (dstat == 0x08)
break;
fallthrough;
case 0x04:
/* Device end interrupt. */
if ((raw = req->info) == NULL)
goto put_tty; /* That shouldn't happen ... */
if (req->type == RAW3215_READ && tty != NULL) {
unsigned int cchar;
count = 160 - req->residual;
EBCASC(raw->inbuf, count);
cchar = ctrlchar_handle(raw->inbuf, count, tty);
switch (cchar & CTRLCHAR_MASK) {
case CTRLCHAR_SYSRQ:
break;
case CTRLCHAR_CTRL:
tty_insert_flip_char(&raw->port, cchar,
TTY_NORMAL);
tty_flip_buffer_push(&raw->port);
break;
case CTRLCHAR_NONE:
if (count < 2 ||
(strncmp(raw->inbuf+count-2, "\252n", 2) &&
strncmp(raw->inbuf+count-2, "^n", 2)) ) {
/* add the auto \n */
raw->inbuf[count] = '\n';
count++;
} else
count -= 2;
tty_insert_flip_string(&raw->port, raw->inbuf,
count);
tty_flip_buffer_push(&raw->port);
break;
}
} else if (req->type == RAW3215_WRITE) {
raw->count -= req->len;
raw->written -= req->len;
}
raw->flags &= ~RAW3215_WORKING;
raw3215_free_req(req);
/* check for empty wait */
if (waitqueue_active(&raw->empty_wait) &&
raw->queued_write == NULL &&
raw->queued_read == NULL) {
wake_up_interruptible(&raw->empty_wait);
}
raw3215_next_io(raw, tty);
break;
default:
/* Strange interrupt, I'll do my best to clean up */
if (req != NULL && req->type != RAW3215_FREE) {
if (req->type == RAW3215_WRITE) {
raw->count -= req->len;
raw->written -= req->len;
}
raw->flags &= ~RAW3215_WORKING;
raw3215_free_req(req);
}
raw3215_next_io(raw, tty);
}
put_tty:
tty_kref_put(tty);
}
/*
* Need to drop data to avoid blocking. Drop as much data as possible.
* This is unqueued part in the buffer and the queued part in the request.
* Also adjust the head position to append new data and set count
* accordingly.
*
* Return number of bytes available in buffer.
*/
static unsigned int raw3215_drop(struct raw3215_info *raw)
{
struct raw3215_req *req;
req = raw->queued_write;
if (req) {
/* Drop queued data and delete request */
raw->written -= req->len;
raw3215_free_req(req);
raw->queued_write = NULL;
}
raw->head = (raw->head - raw->count + raw->written) &
(RAW3215_BUFFER_SIZE - 1);
raw->count = raw->written;
return RAW3215_BUFFER_SIZE - raw->count;
}
/*
* Wait until length bytes are available int the output buffer.
* If drop mode is active and wait condition holds true, start dropping
* data.
* Has to be called with the s390irq lock held. Can be called
* disabled.
*/
static unsigned int raw3215_make_room(struct raw3215_info *raw,
unsigned int length, bool drop)
{
while (RAW3215_BUFFER_SIZE - raw->count < length) {
if (drop)
return raw3215_drop(raw);
/* there might be a request pending */
raw->flags |= RAW3215_FLUSHING;
raw3215_mk_write_req(raw);
raw3215_try_io(raw);
raw->flags &= ~RAW3215_FLUSHING;
#ifdef CONFIG_TN3215_CONSOLE
ccw_device_wait_idle(raw->cdev);
#endif
/* Enough room freed up ? */
if (RAW3215_BUFFER_SIZE - raw->count >= length)
break;
/* there might be another cpu waiting for the lock */
spin_unlock(get_ccwdev_lock(raw->cdev));
udelay(100);
spin_lock(get_ccwdev_lock(raw->cdev));
}
return length;
}
#define RAW3215_COUNT 1
#define RAW3215_STORE 2
/*
* Add text to console buffer. Find tabs in input and calculate size
* including tab replacement.
* This function operates in 2 different modes, depending on parameter
* opmode:
* RAW3215_COUNT: Get the size needed for the input string with
* proper tab replacement calculation.
* Return value is the number of bytes required to store the
* input. However no data is actually stored.
* The parameter todrop is not used.
* RAW3215_STORE: Add data to the console buffer. The parameter todrop is
* valid and contains the number of bytes to be dropped from head of
* string without blocking.
* Return value is the number of bytes copied.
*/
static unsigned int raw3215_addtext(const char *str, unsigned int length,
struct raw3215_info *raw, int opmode,
unsigned int todrop)
{
unsigned int c, ch, i, blanks, expanded_size = 0;
unsigned int column = raw->line_pos;
if (opmode == RAW3215_COUNT)
todrop = 0;
for (c = 0; c < length; ++c) {
blanks = 1;
ch = str[c];
switch (ch) {
case '\n':
expanded_size++;
column = 0;
break;
case '\t':
blanks = TAB_STOP_SIZE - (column % TAB_STOP_SIZE);
column += blanks;
expanded_size += blanks;
ch = ' ';
break;
default:
expanded_size++;
column++;
break;
}
if (opmode == RAW3215_COUNT)
continue;
if (todrop && expanded_size < todrop) /* Drop head data */
continue;
for (i = 0; i < blanks; i++) {
raw->buffer[raw->head] = (char)_ascebc[(int)ch];
raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
raw->count++;
}
raw->line_pos = column;
}
return expanded_size - todrop;
}
/*
* String write routine for 3215 devices
*/
static void raw3215_write(struct raw3215_info *raw, const char *str,
unsigned int length)
{
unsigned int count, avail;
unsigned long flags;
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
count = raw3215_addtext(str, length, raw, RAW3215_COUNT, 0);
avail = raw3215_make_room(raw, count, con3215_drop);
if (avail) {
raw3215_addtext(str, length, raw, RAW3215_STORE,
count - avail);
}
if (!(raw->flags & RAW3215_WORKING)) {
raw3215_mk_write_req(raw);
/* start or queue request */
raw3215_try_io(raw);
}
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
}
/*
* Put character routine for 3215 devices
*/
static void raw3215_putchar(struct raw3215_info *raw, unsigned char ch)
{
raw3215_write(raw, &ch, 1);
}
/*
* Flush routine, it simply sets the flush flag and tries to start
* pending IO.
*/
static void raw3215_flush_buffer(struct raw3215_info *raw)
{
unsigned long flags;
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
if (raw->count > 0) {
raw->flags |= RAW3215_FLUSHING;
raw3215_try_io(raw);
raw->flags &= ~RAW3215_FLUSHING;
}
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
}
/*
* Fire up a 3215 device.
*/
static int raw3215_startup(struct raw3215_info *raw)
{
unsigned long flags;
if (tty_port_initialized(&raw->port))
return 0;
raw->line_pos = 0;
tty_port_set_initialized(&raw->port, true);
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
raw3215_try_io(raw);
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
return 0;
}
/*
* Shutdown a 3215 device.
*/
static void raw3215_shutdown(struct raw3215_info *raw)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long flags;
if (!tty_port_initialized(&raw->port) || (raw->flags & RAW3215_FIXED))
return;
/* Wait for outstanding requests, then free irq */
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
if ((raw->flags & RAW3215_WORKING) ||
raw->queued_write != NULL ||
raw->queued_read != NULL) {
add_wait_queue(&raw->empty_wait, &wait);
set_current_state(TASK_INTERRUPTIBLE);
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
schedule();
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
remove_wait_queue(&raw->empty_wait, &wait);
set_current_state(TASK_RUNNING);
tty_port_set_initialized(&raw->port, true);
}
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
}
static struct raw3215_info *raw3215_alloc_info(void)
{
struct raw3215_info *info;
info = kzalloc(sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA);
if (!info)
return NULL;
info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA);
info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA);
if (!info->buffer || !info->inbuf) {
kfree(info->inbuf);
kfree(info->buffer);
kfree(info);
return NULL;
}
timer_setup(&info->timer, raw3215_timeout, 0);
init_waitqueue_head(&info->empty_wait);
tty_port_init(&info->port);
return info;
}
static void raw3215_free_info(struct raw3215_info *raw)
{
kfree(raw->inbuf);
kfree(raw->buffer);
tty_port_destroy(&raw->port);
kfree(raw);
}
static int raw3215_probe(struct ccw_device *cdev)
{
struct raw3215_info *raw;
int line;
/* Console is special. */
if (raw3215[0] && (raw3215[0] == dev_get_drvdata(&cdev->dev)))
return 0;
raw = raw3215_alloc_info();
if (raw == NULL)
return -ENOMEM;
raw->cdev = cdev;
dev_set_drvdata(&cdev->dev, raw);
cdev->handler = raw3215_irq;
spin_lock(&raw3215_device_lock);
for (line = 0; line < NR_3215; line++) {
if (!raw3215[line]) {
raw3215[line] = raw;
break;
}
}
spin_unlock(&raw3215_device_lock);
if (line == NR_3215) {
raw3215_free_info(raw);
return -ENODEV;
}
return 0;
}
static void raw3215_remove(struct ccw_device *cdev)
{
struct raw3215_info *raw;
unsigned int line;
ccw_device_set_offline(cdev);
raw = dev_get_drvdata(&cdev->dev);
if (raw) {
spin_lock(&raw3215_device_lock);
for (line = 0; line < NR_3215; line++)
if (raw3215[line] == raw)
break;
raw3215[line] = NULL;
spin_unlock(&raw3215_device_lock);
dev_set_drvdata(&cdev->dev, NULL);
raw3215_free_info(raw);
}
}
static int raw3215_set_online(struct ccw_device *cdev)
{
struct raw3215_info *raw;
raw = dev_get_drvdata(&cdev->dev);
if (!raw)
return -ENODEV;
return raw3215_startup(raw);
}
static int raw3215_set_offline(struct ccw_device *cdev)
{
struct raw3215_info *raw;
raw = dev_get_drvdata(&cdev->dev);
if (!raw)
return -ENODEV;
raw3215_shutdown(raw);
return 0;
}
static struct ccw_device_id raw3215_id[] = {
{ CCW_DEVICE(0x3215, 0) },
{ /* end of list */ },
};
static ssize_t con_drop_store(struct device_driver *dev, const char *buf, size_t count)
{
bool drop;
int rc;
rc = kstrtobool(buf, &drop);
if (!rc)
con3215_drop = drop;
return rc ?: count;
}
static ssize_t con_drop_show(struct device_driver *dev, char *buf)
{
return sysfs_emit(buf, "%d\n", con3215_drop ? 1 : 0);
}
static DRIVER_ATTR_RW(con_drop);
static struct attribute *con3215_drv_attrs[] = {
&driver_attr_con_drop.attr,
NULL,
};
static struct attribute_group con3215_drv_attr_group = {
.attrs = con3215_drv_attrs,
NULL,
};
static const struct attribute_group *con3215_drv_attr_groups[] = {
&con3215_drv_attr_group,
NULL,
};
static struct ccw_driver raw3215_ccw_driver = {
.driver = {
.name = "3215",
.groups = con3215_drv_attr_groups,
.owner = THIS_MODULE,
},
.ids = raw3215_id,
.probe = &raw3215_probe,
.remove = &raw3215_remove,
.set_online = &raw3215_set_online,
.set_offline = &raw3215_set_offline,
.int_class = IRQIO_C15,
};
static void handle_write(struct raw3215_info *raw, const char *str, int count)
{
int i;
while (count > 0) {
i = min_t(int, count, RAW3215_BUFFER_SIZE - 1);
raw3215_write(raw, str, i);
count -= i;
str += i;
}
}
#ifdef CONFIG_TN3215_CONSOLE
/*
* Write a string to the 3215 console
*/
static void con3215_write(struct console *co, const char *str, unsigned int count)
{
handle_write(raw3215[0], str, count);
}
static struct tty_driver *con3215_device(struct console *c, int *index)
{
*index = c->index;
return tty3215_driver;
}
/*
* The below function is called as a panic/reboot notifier before the
* system enters a disabled, endless loop.
*
* Notice we must use the spin_trylock() alternative, to prevent lockups
* in atomic context (panic routine runs with secondary CPUs, local IRQs
* and preemption disabled).
*/
static int con3215_notify(struct notifier_block *self,
unsigned long event, void *data)
{
struct raw3215_info *raw;
unsigned long flags;
raw = raw3215[0]; /* console 3215 is the first one */
if (!spin_trylock_irqsave(get_ccwdev_lock(raw->cdev), flags))
return NOTIFY_DONE;
raw3215_make_room(raw, RAW3215_BUFFER_SIZE, false);
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
return NOTIFY_DONE;
}
static struct notifier_block on_panic_nb = {
.notifier_call = con3215_notify,
.priority = INT_MIN + 1, /* run the callback late */
};
static struct notifier_block on_reboot_nb = {
.notifier_call = con3215_notify,
.priority = INT_MIN + 1, /* run the callback late */
};
/*
* The console structure for the 3215 console
*/
static struct console con3215 = {
.name = "ttyS",
.write = con3215_write,
.device = con3215_device,
.flags = CON_PRINTBUFFER,
};
/*
* 3215 console initialization code called from console_init().
*/
static int __init con3215_init(void)
{
struct ccw_device *cdev;
struct raw3215_info *raw;
struct raw3215_req *req;
int i;
/* Check if 3215 is to be the console */
if (!CONSOLE_IS_3215)
return -ENODEV;
/* Set the console mode for VM */
if (MACHINE_IS_VM) {
cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
}
/* allocate 3215 request structures */
raw3215_freelist = NULL;
for (i = 0; i < NR_3215_REQ; i++) {
req = kzalloc(sizeof(struct raw3215_req), GFP_KERNEL | GFP_DMA);
if (!req)
return -ENOMEM;
req->next = raw3215_freelist;
raw3215_freelist = req;
}
cdev = ccw_device_create_console(&raw3215_ccw_driver);
if (IS_ERR(cdev))
return -ENODEV;
raw3215[0] = raw = raw3215_alloc_info();
raw->cdev = cdev;
dev_set_drvdata(&cdev->dev, raw);
cdev->handler = raw3215_irq;
raw->flags |= RAW3215_FIXED;
if (ccw_device_enable_console(cdev)) {
ccw_device_destroy_console(cdev);
raw3215_free_info(raw);
raw3215[0] = NULL;
return -ENODEV;
}
/* Request the console irq */
if (raw3215_startup(raw) != 0) {
raw3215_free_info(raw);
raw3215[0] = NULL;
return -ENODEV;
}
atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
register_reboot_notifier(&on_reboot_nb);
register_console(&con3215);
return 0;
}
console_initcall(con3215_init);
#endif
static int tty3215_install(struct tty_driver *driver, struct tty_struct *tty)
{
struct raw3215_info *raw;
raw = raw3215[tty->index];
if (raw == NULL)
return -ENODEV;
tty->driver_data = raw;
return tty_port_install(&raw->port, driver, tty);
}
/*
* tty3215_open
*
* This routine is called whenever a 3215 tty is opened.
*/
static int tty3215_open(struct tty_struct *tty, struct file * filp)
{
struct raw3215_info *raw = tty->driver_data;
tty_port_tty_set(&raw->port, tty);
/*
* Start up 3215 device
*/
return raw3215_startup(raw);
}
/*
* tty3215_close()
*
* This routine is called when the 3215 tty is closed. We wait
* for the remaining request to be completed. Then we clean up.
*/
static void tty3215_close(struct tty_struct *tty, struct file * filp)
{
struct raw3215_info *raw = tty->driver_data;
if (raw == NULL || tty->count > 1)
return;
tty->closing = 1;
/* Shutdown the terminal */
raw3215_shutdown(raw);
tty->closing = 0;
tty_port_tty_set(&raw->port, NULL);
}
/*
* Returns the amount of free space in the output buffer.
*/
static unsigned int tty3215_write_room(struct tty_struct *tty)
{
struct raw3215_info *raw = tty->driver_data;
/* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */
if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0)
return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE;
else
return 0;
}
/*
* String write routine for 3215 ttys
*/
static ssize_t tty3215_write(struct tty_struct *tty, const u8 *buf,
size_t count)
{
handle_write(tty->driver_data, buf, count);
return count;
}
/*
* Put character routine for 3215 ttys
*/
static int tty3215_put_char(struct tty_struct *tty, u8 ch)
{
struct raw3215_info *raw = tty->driver_data;
raw3215_putchar(raw, ch);
return 1;
}
static void tty3215_flush_chars(struct tty_struct *tty)
{
}
/*
* Returns the number of characters in the output buffer
*/
static unsigned int tty3215_chars_in_buffer(struct tty_struct *tty)
{
struct raw3215_info *raw = tty->driver_data;
return raw->count;
}
static void tty3215_flush_buffer(struct tty_struct *tty)
{
struct raw3215_info *raw = tty->driver_data;
raw3215_flush_buffer(raw);
tty_wakeup(tty);
}
/*
* Disable reading from a 3215 tty
*/
static void tty3215_throttle(struct tty_struct *tty)
{
struct raw3215_info *raw = tty->driver_data;
raw->flags |= RAW3215_THROTTLED;
}
/*
* Enable reading from a 3215 tty
*/
static void tty3215_unthrottle(struct tty_struct *tty)
{
struct raw3215_info *raw = tty->driver_data;
unsigned long flags;
if (raw->flags & RAW3215_THROTTLED) {
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
raw->flags &= ~RAW3215_THROTTLED;
raw3215_try_io(raw);
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
}
}
/*
* Disable writing to a 3215 tty
*/
static void tty3215_stop(struct tty_struct *tty)
{
struct raw3215_info *raw = tty->driver_data;
raw->flags |= RAW3215_STOPPED;
}
/*
* Enable writing to a 3215 tty
*/
static void tty3215_start(struct tty_struct *tty)
{
struct raw3215_info *raw = tty->driver_data;
unsigned long flags;
if (raw->flags & RAW3215_STOPPED) {
spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
raw->flags &= ~RAW3215_STOPPED;
raw3215_try_io(raw);
spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
}
}
static const struct tty_operations tty3215_ops = {
.install = tty3215_install,
.open = tty3215_open,
.close = tty3215_close,
.write = tty3215_write,
.put_char = tty3215_put_char,
.flush_chars = tty3215_flush_chars,
.write_room = tty3215_write_room,
.chars_in_buffer = tty3215_chars_in_buffer,
.flush_buffer = tty3215_flush_buffer,
.throttle = tty3215_throttle,
.unthrottle = tty3215_unthrottle,
.stop = tty3215_stop,
.start = tty3215_start,
};
static int __init con3215_setup_drop(char *str)
{
bool drop;
int rc;
rc = kstrtobool(str, &drop);
if (!rc)
con3215_drop = drop;
return rc;
}
early_param("con3215_drop", con3215_setup_drop);
/*
* 3215 tty registration code called from tty_init().
* Most kernel services (incl. kmalloc) are available at this poimt.
*/
static int __init tty3215_init(void)
{
struct tty_driver *driver;
int ret;
if (!CONSOLE_IS_3215)
return 0;
driver = tty_alloc_driver(NR_3215, TTY_DRIVER_REAL_RAW);
if (IS_ERR(driver))
return PTR_ERR(driver);
ret = ccw_driver_register(&raw3215_ccw_driver);
if (ret) {
tty_driver_kref_put(driver);
return ret;
}
/*
* Initialize the tty_driver structure
* Entries in tty3215_driver that are NOT initialized:
* proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
*/
driver->driver_name = "tty3215";
driver->name = "ttyS";
driver->major = TTY_MAJOR;
driver->minor_start = 64;
driver->type = TTY_DRIVER_TYPE_SYSTEM;
driver->subtype = SYSTEM_TYPE_TTY;
driver->init_termios = tty_std_termios;
driver->init_termios.c_iflag = IGNBRK | IGNPAR;
driver->init_termios.c_oflag = ONLCR;
driver->init_termios.c_lflag = ISIG;
tty_set_operations(driver, &tty3215_ops);
ret = tty_register_driver(driver);
if (ret) {
tty_driver_kref_put(driver);
return ret;
}
tty3215_driver = driver;
return 0;
}
device_initcall(tty3215_init);