patch-2.3.99-pre8 linux/drivers/s390/char/con3215.c

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diff -u --recursive --new-file v2.3.99-pre7/linux/drivers/s390/char/con3215.c linux/drivers/s390/char/con3215.c
@@ -0,0 +1,1129 @@
+/*
+ *  drivers/s390/char/con3215.c
+ *    3215 line mode terminal driver.
+ *
+ *  S390 version
+ *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kdev_t.h>
+#include <linux/tty.h>
+#include <linux/vt_kern.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/interrupt.h>
+
+#include <linux/malloc.h>
+#include <linux/bootmem.h>
+#include <asm/io.h>
+#include <asm/ebcdic.h>
+#include <asm/uaccess.h>
+
+#include "../../../arch/s390/kernel/cpcmd.h"
+#include <asm/irq.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_CCWLEN  3968      /* max. bytes to write with one ccw */
+#define RAW3215_NR_CCWS	    ((RAW3215_BUFFER_SIZE/RAW3215_MAX_CCWLEN)+2)
+#define RAW3215_TIMEOUT	    HZ/10     /* time for delayed output */
+
+#define RAW3215_FIXED	    1	      /* 3215 console device is not be freed */
+#define RAW3215_ACTIVE	    2	      /* set if the device is in use */
+#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_CLOSING	    32	      /* set while in close process */
+#define RAW3215_TIMER_RUNS  64	      /* set if the output delay timer is on */
+#define RAW3215_FLUSHING    128	      /* set to flush buffer (no delay) */
+#define RAW3215_BH_PENDING  256       /* indication for bh scheduling */
+
+struct _raw3215_info;		      /* forward declaration ... */
+
+int raw3215_condevice = -1;           /* preset console device */
+
+/*
+ * Request types for a 3215 device
+ */
+typedef enum {
+	RAW3215_FREE, RAW3215_READ, RAW3215_WRITE
+} raw3215_type;
+
+/*
+ * Request structure for a 3215 device
+ */
+typedef struct _raw3215_req {
+	raw3215_type type;	      /* type of the request */
+	int start, end;		      /* start/end index into output buffer */
+	int residual;		      /* residual count for read request */
+	ccw1_t 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 */
+} raw3215_req  __attribute__ ((aligned(8)));
+
+typedef struct _raw3215_info {
+	int flags;		      /* state flags */
+	int irq;		      /* interrupt number to do_IO */
+	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 */
+	devstat_t devstat;	      /* device status structure for do_IO */
+	struct tty_struct *tty;	      /* pointer to tty structure if present */
+	struct tq_struct tqueue;      /* task queue to bottom half */
+	raw3215_req *queued_read;     /* pointer to queued read requests */
+	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 */
+	char *message;                /* pending message from raw3215_irq */
+	int msg_dstat;                /* dstat for pending message */
+	int msg_cstat;                /* cstat for pending message */
+} raw3215_info;
+
+static raw3215_info *raw3215[NR_3215];	/* array of 3215 devices structures */
+static raw3215_req *raw3215_freelist;	/* list of free request structures */
+static spinlock_t raw3215_freelist_lock;/* spinlock to protect free list */
+
+static struct tty_driver tty3215_driver;
+static struct tty_struct *tty3215_table[NR_3215];
+static struct termios *tty3215_termios[NR_3215];
+static struct termios *tty3215_termios_locked[NR_3215];
+static int tty3215_refcount;
+
+#ifndef MIN
+#define MIN(a,b)	((a) < (b) ? (a) : (b))
+#endif
+
+static int __init con3215_setup(char *str)
+{
+        int vdev;
+
+        vdev = simple_strtoul(str,&str,16);
+        if (vdev >= 0 && vdev < 65536)
+                raw3215_condevice = vdev;
+        return 1;
+}
+
+__setup("condev=", con3215_setup);
+
+/*
+ * Get a request structure from the free list
+ */
+extern inline raw3215_req *raw3215_alloc_req(void) {
+	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
+ */
+extern inline void raw3215_free_req(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);
+}
+
+/*
+ * Get a write request structure. That is either a new or the last
+ * queued write request. The request structure is set up in 
+ * raw3215_mk_write_ccw.
+ */
+static raw3215_req *raw3215_mk_write_req(raw3215_info *raw)
+{
+	raw3215_req *req;
+
+	/* 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;
+		req->start = raw->head;
+	} else
+		raw->queued_write = NULL;
+	return req;
+}
+
+/*
+ * Get a read request structure. 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 raw3215_req *raw3215_mk_read_req(raw3215_info *raw)
+{
+	raw3215_req *req;
+
+	/* 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;
+	} else
+		raw->queued_read = NULL;
+	return req;
+}
+
+/*
+ * Set up a write request with the information from the main structure.
+ * A ccw chain is created that writes everything in the output buffer
+ * to the 3215 device.
+ */
+static int raw3215_mk_write_ccw(raw3215_info *raw, raw3215_req *req)
+{
+	ccw1_t *ccw;
+	int len, count, ix;
+
+	ccw = req->ccws;
+	req->end = (raw->head - 1) & (RAW3215_BUFFER_SIZE - 1);
+	len = ((req->end - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
+	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 =
+			(void *) virt_to_phys(raw->buffer + ix);
+		count = (len > RAW3215_MAX_CCWLEN) ? 
+			RAW3215_MAX_CCWLEN : 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++;
+	}
+	return len;
+}
+
+/*
+ * Set up a read request that reads up to 160 byte from the 3215 device.
+ */
+static void raw3215_mk_read_ccw(raw3215_info *raw, raw3215_req *req)
+{
+	ccw1_t *ccw;
+
+	ccw = req->ccws;
+	ccw->cmd_code = 0x0A; /* read inquiry */
+	ccw->flags = 0x20;    /* ignore incorrect length */
+	ccw->count = 160;
+	ccw->cda = (void *) virt_to_phys(raw->inbuf);
+}
+
+/*
+ * Start a read or a write request
+ */
+static void raw3215_start_io(raw3215_info *raw)
+{
+	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 = do_IO(raw->irq, req->ccws, (__u32) 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 = do_IO(raw->irq, req->ccws, (__u32) 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(unsigned long __data)
+{
+	raw3215_info *raw = (raw3215_info *) __data;
+	unsigned long flags;
+
+	s390irq_spin_lock_irqsave(raw->irq, flags);
+	if (raw->flags & RAW3215_TIMER_RUNS) {
+		del_timer(&raw->timer);
+		raw->flags &= ~RAW3215_TIMER_RUNS;
+		raw3215_start_io(raw);
+	}
+	s390irq_spin_unlock_irqrestore(raw->irq, flags);
+}
+
+/*
+ * Function to conditionally start an IO. A read is started immediatly,
+ * a write is only started immediatly if the flush flag is on or the
+ * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
+ * done immediatly a timer is started with a delay of RAW3215_TIMEOUT.
+ */
+extern inline void raw3215_try_io(raw3215_info *raw)
+{
+	if (!(raw->flags & RAW3215_ACTIVE))
+		return;
+	if (raw->queued_read != NULL)
+		raw3215_start_io(raw);
+	else if (raw->queued_write != NULL) {
+		if (raw->count >= RAW3215_MIN_WRITE ||
+		    (raw->flags & RAW3215_FLUSHING)) {
+			/* execute write requests bigger than minimum size */
+			raw3215_start_io(raw);
+			if (raw->flags & RAW3215_TIMER_RUNS) {
+				del_timer(&raw->timer);
+				raw->flags &= ~RAW3215_TIMER_RUNS;
+			}
+		} else if (!(raw->flags & RAW3215_TIMER_RUNS)) {
+			/* delay small writes */
+			init_timer(&raw->timer);
+			raw->timer.expires = RAW3215_TIMEOUT + jiffies;
+			raw->timer.data = (unsigned long) raw;
+			raw->timer.function = raw3215_timeout;
+			add_timer(&raw->timer);
+			raw->flags |= RAW3215_TIMER_RUNS;
+		}
+	}
+}
+
+/*
+ * The bottom half handler routine for 3215 devices. It tries to start
+ * the next IO and wakes up processes waiting on the tty.
+ */
+static void raw3215_softint(void *data)
+{
+	raw3215_info *raw;
+	struct tty_struct *tty;
+	unsigned long flags;
+
+	raw = (raw3215_info *) data;
+	s390irq_spin_lock_irqsave(raw->irq, flags);
+	raw3215_try_io((raw3215_info *) data);
+        raw->flags &= ~RAW3215_BH_PENDING;
+	s390irq_spin_unlock_irqrestore(raw->irq, flags);
+	/* Check for pending message from raw3215_irq */
+	if (raw->message != NULL) {
+		printk(raw->message, raw->irq, raw->msg_dstat, raw->msg_cstat);
+		raw->message = NULL;
+	}
+	tty = raw->tty;
+	if (tty != NULL &&
+	    RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) {
+		if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
+		    tty->ldisc.write_wakeup)
+			(tty->ldisc.write_wakeup)(tty);
+		wake_up_interruptible(&tty->write_wait);
+	}
+}
+
+/*
+ * Function to safely add raw3215_softint to tq_immediate.
+ * The s390irq spinlock must be held.
+ */
+static inline void raw3215_sched_bh(raw3215_info *raw)
+{
+        if (raw->flags & RAW3215_BH_PENDING)
+                return;       /* already pending */
+        raw->flags |= RAW3215_BH_PENDING;
+        raw->tqueue.routine = raw3215_softint;
+        raw->tqueue.data = raw;
+        queue_task(&raw->tqueue, &tq_immediate);
+        mark_bh(IMMEDIATE_BH);
+}
+
+/*
+ * Find the raw3215_info structure associated with irq
+ */
+static inline raw3215_info *raw3215_find_info(int irq) {
+	raw3215_info *raw;
+	int i;
+
+	for (i = 0; i < NR_3215; i++) {
+		raw = raw3215[i];
+		if (raw != NULL && raw->irq == irq &&
+		    (raw->flags & RAW3215_ACTIVE))
+			break;
+	}
+	return (i >= NR_3215) ? NULL : raw;
+}
+
+/*
+ * Interrupt routine, called from Ingo's I/O layer
+ */
+static void raw3215_irq(int irq, void *int_parm, struct pt_regs *regs)
+{
+	raw3215_info *raw;
+	raw3215_req *req;
+	struct tty_struct *tty;
+	devstat_t *stat;
+        int cstat, dstat;
+	int count, slen;
+
+	stat = (devstat_t *) int_parm;
+	req = (raw3215_req *) stat->intparm;
+	cstat = stat->cstat;
+	dstat = stat->dstat;
+	if (cstat != 0) {
+		raw = raw3215_find_info(irq);
+		if (raw != NULL) {
+			raw->message = KERN_WARNING
+				"Got nonzero channel status in raw3215_irq "
+				"(dev %i, dev sts 0x%2x, sch sts 0x%2x)";
+			raw->msg_dstat = dstat;
+			raw->msg_cstat = cstat;
+                        raw3215_sched_bh(raw);
+		}
+	}
+        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 */
+		if ((raw = raw3215_find_info(irq)) == NULL)
+			return;              /* That shouldn't happen ... */
+		/* Setup a read request */
+		req = raw3215_mk_read_req(raw);
+		raw3215_mk_read_ccw(raw, req);
+		raw->queued_read = req;
+                if (MACHINE_IS_P390)
+                        memset(raw->inbuf, 0, RAW3215_INBUF_SIZE);
+                raw3215_sched_bh(raw);
+		break;
+	case 0x08:
+	case 0x0C:
+		/* Channel end interrupt. */
+		raw = req->info;
+		if (req->type == RAW3215_READ) {
+			/* store residual count, then wait for device end */
+			req->residual = stat->rescnt;
+		}
+		if (dstat == 0x08)
+			break;
+	case 0x04:
+		/* Device end interrupt. */
+		raw = req->info;
+		if (req->type == RAW3215_READ && raw->tty != NULL) {
+			tty = raw->tty;
+                        count = 160 - req->residual;
+                        if (MACHINE_IS_P390) {
+                                slen = strnlen(raw->inbuf, RAW3215_INBUF_SIZE);
+                                if (count > slen)
+                                        count = slen;
+                        } else
+			if (count >= TTY_FLIPBUF_SIZE - tty->flip.count)
+				count = TTY_FLIPBUF_SIZE - tty->flip.count - 1;
+			EBCASC(raw->inbuf, count);
+			if (count == 2 && (
+                            /* hat is 0xb0 in codepage 037 (US etc.) and thus */
+                            /* converted to 0x5e in ascii ('^') */
+                            strncmp(raw->inbuf, "^c", 2) == 0 ||
+                            /* hat is 0xb0 in several other codepages (German,*/
+                            /* UK, ...) and thus converted to ascii octal 252 */
+                            strncmp(raw->inbuf, "\252c", 2) == 0) ) {
+				/* emulate a control C = break */
+				tty->flip.count++;
+				*tty->flip.flag_buf_ptr++ = TTY_NORMAL;
+				*tty->flip.char_buf_ptr++ = INTR_CHAR(tty);
+				tty_flip_buffer_push(raw->tty);
+			} else if (count == 2 && (
+                                   strncmp(raw->inbuf, "^d", 2) == 0 ||
+                                    strncmp(raw->inbuf, "\252d", 2) == 0) ) {
+				/* emulate a control D = end of file */
+				tty->flip.count++;
+				*tty->flip.flag_buf_ptr++ = TTY_NORMAL;
+				*tty->flip.char_buf_ptr++ = EOF_CHAR(tty);
+				tty_flip_buffer_push(raw->tty);
+			} else if (count == 2 && (
+                                   strncmp(raw->inbuf, "^z", 2) == 0 ||
+                                    strncmp(raw->inbuf, "\252z", 2) == 0) ) {
+				/* emulate a control Z = suspend */
+				tty->flip.count++;
+				*tty->flip.flag_buf_ptr++ = TTY_NORMAL;
+				*tty->flip.char_buf_ptr++ = SUSP_CHAR(tty);
+				tty_flip_buffer_push(raw->tty);
+			} else {
+				memcpy(tty->flip.char_buf_ptr,
+				       raw->inbuf, count);
+				if (count < 2 ||
+                                    (strncmp(raw->inbuf+count-2, "^n", 2) ||
+                                    strncmp(raw->inbuf+count-2, "\252n", 2)) ) {					/* don't add the auto \n */
+					tty->flip.char_buf_ptr[count] = '\n';
+					memset(tty->flip.flag_buf_ptr,
+					       TTY_NORMAL, count + 1);
+					count++;
+				} else
+					count-=2;
+				tty->flip.char_buf_ptr += count;
+				tty->flip.flag_buf_ptr += count;
+				tty->flip.count += count;
+				tty_flip_buffer_push(raw->tty);
+			}
+		} else if (req->type == RAW3215_WRITE) {
+			raw->count -= ((req->end - req->start) &
+				       (RAW3215_BUFFER_SIZE - 1)) + 1;
+		}
+		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_sched_bh(raw);
+		break;
+	default:
+		/* Strange interrupt, I'll do my best to clean up */
+                if ((raw = raw3215_find_info(irq)) == NULL)
+                        return;              /* That shouldn't happen ... */
+                if (raw == NULL) break;
+		if (req != NULL && req->type != RAW3215_FREE) {
+		        if (req->type == RAW3215_WRITE) 
+			        raw->count -= ((req->end - req->start) &
+				              (RAW3215_BUFFER_SIZE-1))+1;
+                        raw->flags &= ~RAW3215_WORKING;
+                        raw3215_free_req(req);
+		}
+		raw->message = KERN_WARNING
+			"Spurious interrupt in in raw3215_irq "
+			"(dev %i, dev sts 0x%2x, sch sts 0x%2x)";
+		raw->msg_dstat = dstat;
+		raw->msg_cstat = cstat;
+                raw3215_sched_bh(raw);
+	}
+	return;
+}
+
+/*
+ * String write routine for 3215 devices
+ */
+static int
+raw3215_write(raw3215_info *raw, const char *str,
+	      int from_user, unsigned int length)
+{
+	raw3215_req *req;
+	unsigned long flags;
+	int ret, c;
+	int count;
+	
+	ret = 0;
+	while (length > 0) {
+		s390irq_spin_lock_irqsave(raw->irq, flags);
+		count = (length > RAW3215_BUFFER_SIZE) ?
+					     RAW3215_BUFFER_SIZE : length;
+		length -= count;
+
+		while (RAW3215_BUFFER_SIZE - raw->count < count) {
+			/* there might be a request pending */
+			raw3215_try_io(raw);
+			if (wait_cons_dev(raw->irq) != 0) {
+				/* that shouldn't happen */
+				raw->count = 0;
+			} 
+		}
+
+		req = raw3215_mk_write_req(raw);
+		/* copy string to output buffer and convert it to EBCDIC */
+		if (from_user) {
+			while (1) {
+				c = MIN(count,
+					MIN(RAW3215_BUFFER_SIZE - raw->count,
+					    RAW3215_BUFFER_SIZE - raw->head));
+				if (c <= 0)
+					break;
+				c -= copy_from_user(raw->buffer + raw->head,
+						    str, c);
+				if (c == 0) {
+					if (!ret)
+						ret = -EFAULT;
+					break;
+				}
+				ASCEBC(raw->buffer + raw->head, c);
+				raw->head = (raw->head + c) &
+					    (RAW3215_BUFFER_SIZE - 1);
+				raw->count += c;
+				str += c;
+				count -= c;
+				ret += c;
+			}
+		} else {
+			while (1) {
+				c = MIN(count,
+					MIN(RAW3215_BUFFER_SIZE - raw->count,
+					    RAW3215_BUFFER_SIZE - raw->head));
+				if (c <= 0)
+					break;
+				memcpy(raw->buffer + raw->head, str, c);
+				ASCEBC(raw->buffer + raw->head, c);
+				raw->head = (raw->head + c) &
+					    (RAW3215_BUFFER_SIZE - 1);
+				raw->count += c;
+				str += c;
+				count -= c;
+				ret += c;
+			}
+		}
+		raw3215_mk_write_ccw(raw, req);
+		raw->queued_write = req;
+		/* start or queue request */
+		raw3215_try_io(raw);
+		s390irq_spin_unlock_irqrestore(raw->irq, flags);
+
+	}
+
+	return ret;
+}
+
+/*
+ * Put character routine for 3215 devices
+ */
+static void raw3215_putchar(raw3215_info *raw, unsigned char ch)
+{
+	raw3215_req *req;
+	unsigned long flags;
+
+	s390irq_spin_lock_irqsave(raw->irq, flags);
+	while (RAW3215_BUFFER_SIZE - raw->count < 1) {
+		/* there might be a request pending */
+		raw3215_try_io(raw);
+		if (wait_cons_dev(raw->irq) != 0) {
+			/* that shouldn't happen */
+			raw->count = 0;
+		}
+	}
+
+	req = raw3215_mk_write_req(raw);
+	raw->buffer[raw->head] = (char) _ascebc[(int) ch];
+	raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
+	raw->count++;
+	raw3215_mk_write_ccw(raw, req);
+	raw->queued_write = req;
+	/* start or queue request */
+	raw3215_try_io(raw);
+	s390irq_spin_unlock_irqrestore(raw->irq, flags);
+}
+
+/*
+ * Flush routine, it simply sets the flush flag and tries to start 
+ * pending IO.
+ */
+static void raw3215_flush_buffer(raw3215_info *raw)
+{
+	unsigned long flags;
+
+	s390irq_spin_lock_irqsave(raw->irq, flags);
+	if (raw->count > 0) {
+		raw->flags |= RAW3215_FLUSHING;
+		raw3215_try_io(raw);
+		raw->flags &= ~RAW3215_FLUSHING;
+	}
+	s390irq_spin_unlock_irqrestore(raw->irq, flags);
+}
+
+/*
+ * Fire up a 3215 device.
+ */
+static int raw3215_startup(raw3215_info *raw)
+{
+	unsigned long flags;
+
+	if (raw->flags & RAW3215_ACTIVE)
+		return 0;
+	if (request_irq(raw->irq, raw3215_irq, SA_INTERRUPT,
+			"3215 terminal driver", &raw->devstat) != 0)
+		return -1;
+	raw->flags |= RAW3215_ACTIVE;
+	s390irq_spin_lock_irqsave(raw->irq, flags);
+	raw3215_try_io(raw);
+	s390irq_spin_unlock_irqrestore(raw->irq, flags);
+
+	return 0;	
+}
+
+/*
+ * Shutdown a 3215 device.
+ */
+static void raw3215_shutdown(raw3215_info *raw)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	unsigned long flags;
+
+	if (!(raw->flags & RAW3215_ACTIVE) || (raw->flags & RAW3215_FIXED))
+		return;
+	/* Wait for outstanding requests, then free irq */
+	s390irq_spin_lock_irqsave(raw->irq, flags);
+	if ((raw->flags & RAW3215_WORKING) ||
+	    raw->queued_write != NULL ||
+	    raw->queued_read != NULL) {
+		raw->flags |= RAW3215_CLOSING;
+		add_wait_queue(&raw->empty_wait, &wait);
+		current->state = TASK_INTERRUPTIBLE;
+                s390irq_spin_unlock_irqrestore(raw->irq, flags);
+		schedule();
+		s390irq_spin_lock_irqsave(raw->irq, flags);
+                current->state = TASK_RUNNING;
+		raw->flags &= ~(RAW3215_ACTIVE | RAW3215_CLOSING);
+	}
+	free_irq(raw->irq, NULL);
+	s390irq_spin_unlock_irqrestore(raw->irq, flags);
+}
+
+static int
+raw3215_find_dev(int number)
+{
+	dev_info_t dinfo;
+	int irq;
+	int count;
+
+	irq = get_irq_first();
+	count = 0;
+        while (count <= number && irq != -ENODEV) {
+                if (get_dev_info(irq, &dinfo) == -ENODEV)
+                        break;
+                if (dinfo.devno == raw3215_condevice ||
+                    dinfo.sid_data.cu_type == 0x3215) {
+                        count++;
+                    if (count > number)
+                        return irq;
+                }
+                irq = get_irq_next(irq);
+        }
+        return -1;            /* console not found */
+}
+
+#ifdef CONFIG_3215_CONSOLE
+
+/*
+ * Try to request the console IRQ. Called from init/main.c
+ */
+int con3215_activate(void)
+{
+	raw3215_info *raw;
+
+        if (!MACHINE_IS_VM && !MACHINE_IS_P390)
+                return 0;
+	raw = raw3215[0];  /* 3215 console is the first one */
+	if (raw->irq == -1) /* now console device found in con3215_init */
+		return -1;
+	return raw3215_startup(raw);
+}
+
+/*
+ * Write a string to the 3215 console
+ */
+static void
+con3215_write(struct console *co, const char *str, unsigned int count)
+{
+	raw3215_info *raw;
+
+	if (count <= 0)
+		return;
+	raw = raw3215[0];  /* console 3215 is the first one */
+	raw3215_write(raw, str, 0, count);
+}
+
+kdev_t con3215_device(struct console *c)
+{
+	return MKDEV(TTY_MAJOR, c->index);
+}
+
+/*
+ * panic() calls console_unblank before the system enters a
+ * disabled, endless loop.
+ */
+void con3215_unblank(void)
+{
+	raw3215_info *raw;
+	unsigned long flags;
+
+	raw = raw3215[0];  /* console 3215 is the first one */
+	s390irq_spin_lock_irqsave(raw->irq, flags);
+	while (raw->count > 0) {
+		/* there might be a request pending */
+		raw->flags |= RAW3215_FLUSHING;
+		raw3215_try_io(raw);
+		if (wait_cons_dev(raw->irq) != 0) {
+			/* that shouldn't happen */
+			raw->count = 0;
+		}
+		raw->flags &= ~RAW3215_FLUSHING;
+	}
+	s390irq_spin_unlock_irqrestore(raw->irq, flags);
+}
+
+static int __init con3215_consetup(struct console *co, char *options)
+{
+	return 0;
+}
+
+/*
+ *  The console structure for the 3215 console
+ */
+static struct console con3215 = {
+	"tty3215",
+	con3215_write,
+	NULL,
+	con3215_device,
+	NULL,
+	con3215_unblank,
+	con3215_consetup,
+	CON_PRINTBUFFER,
+	0,
+	0,
+	NULL
+};
+
+#endif
+
+/*
+ * tty3215_open
+ *
+ * This routine is called whenever a 3215 tty is opened.
+ */
+static int tty3215_open(struct tty_struct *tty, struct file * filp)
+{
+	raw3215_info *raw;
+	int retval, line;
+
+	line = MINOR(tty->device) - tty->driver.minor_start;
+	if ((line < 0) || (line >= NR_3215))
+		return -ENODEV;
+
+	raw = raw3215[line];
+	if (raw == NULL) {
+		raw = kmalloc(sizeof(raw3215_info) +
+			      RAW3215_INBUF_SIZE, GFP_KERNEL);
+		if (raw == NULL)
+			return -ENOMEM;
+		raw->irq = raw3215_find_dev(line);
+		if (raw->irq == -1) {
+			kfree(raw);
+			return -ENODEV;
+		}
+		raw->inbuf = (char *) raw + sizeof(raw3215_info);
+		memset(raw, 0, sizeof(raw3215_info));
+		raw->buffer = (char *) kmalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL);
+		if (raw->buffer == NULL) {
+			kfree_s(raw, sizeof(raw3215_info));
+			return -ENOMEM;
+		}
+		raw->tqueue.routine = raw3215_softint;
+		raw->tqueue.data = raw;
+                init_waitqueue_head(&raw->empty_wait);
+		raw3215[line] = raw;
+	}
+
+	tty->driver_data = raw;
+	raw->tty = tty;
+
+	tty->low_latency = 0;  /* don't use bottom half for pushing chars */
+	/*
+	 * Start up 3215 device
+	 */
+	retval = raw3215_startup(raw);
+	if (retval)
+		return retval;
+
+	return 0;
+}
+
+/*
+ * 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)
+{
+	raw3215_info *raw;
+
+	raw = (raw3215_info *) tty->driver_data;
+	if (raw == NULL || tty->count > 1)
+		return;
+	tty->closing = 1;
+	/* Shutdown the terminal */
+	raw3215_shutdown(raw);
+	tty->closing = 0;
+	raw->tty = NULL;
+}
+
+/*
+ * Returns the amount of free space in the output buffer.
+ */
+static int tty3215_write_room(struct tty_struct *tty)
+{
+	raw3215_info *raw;
+				
+	raw = (raw3215_info *) tty->driver_data;
+	return RAW3215_BUFFER_SIZE - raw->count;
+}
+
+/*
+ * String write routine for 3215 ttys
+ */
+static int tty3215_write(struct tty_struct * tty, int from_user,
+		    const unsigned char *buf, int count)
+{
+	raw3215_info *raw;
+	int ret;
+				
+	if (!tty)
+		return 0;
+	raw = (raw3215_info *) tty->driver_data;
+	ret = raw3215_write(raw, buf, from_user, count);
+	return ret;
+}
+
+/*
+ * Put character routine for 3215 ttys
+ */
+static void tty3215_put_char(struct tty_struct *tty, unsigned char ch)
+{
+	raw3215_info *raw;
+
+	if (!tty)
+		return;
+	raw = (raw3215_info *) tty->driver_data;
+	raw3215_putchar(raw, ch);
+}
+
+static void tty3215_flush_chars(struct tty_struct *tty)
+{
+}
+
+/*
+ * Returns the number of characters in the output buffer
+ */
+static int tty3215_chars_in_buffer(struct tty_struct *tty)
+{
+	raw3215_info *raw;
+
+	raw = (raw3215_info *) tty->driver_data;
+	return raw->count;
+}
+
+static void tty3215_flush_buffer(struct tty_struct *tty)
+{
+	raw3215_info *raw;
+
+	raw = (raw3215_info *) tty->driver_data;
+	raw3215_flush_buffer(raw);
+	wake_up_interruptible(&tty->write_wait);
+	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
+	    tty->ldisc.write_wakeup)
+		(tty->ldisc.write_wakeup)(tty);
+}
+
+/*
+ * Currently we don't have any io controls for 3215 ttys
+ */
+static int tty3215_ioctl(struct tty_struct *tty, struct file * file,
+		    unsigned int cmd, unsigned long arg)
+{
+	if (tty->flags & (1 << TTY_IO_ERROR))
+		return -EIO;
+
+	switch (cmd) {
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+/*
+ * Disable reading from a 3215 tty
+ */
+static void tty3215_throttle(struct tty_struct * tty)
+{
+	raw3215_info *raw;
+
+	raw = (raw3215_info *) tty->driver_data;
+	raw->flags |= RAW3215_THROTTLED;
+}
+
+/*
+ * Enable reading from a 3215 tty
+ */
+static void tty3215_unthrottle(struct tty_struct * tty)
+{
+	raw3215_info *raw;
+	unsigned long flags;
+
+	raw = (raw3215_info *) tty->driver_data;
+	if (raw->flags & RAW3215_THROTTLED) {
+		s390irq_spin_lock_irqsave(raw->irq, flags);
+		raw->flags &= ~RAW3215_THROTTLED;
+		raw3215_try_io(raw);
+		s390irq_spin_unlock_irqrestore(raw->irq, flags);
+	}
+}
+
+/*
+ * Disable writing to a 3215 tty
+ */
+static void tty3215_stop(struct tty_struct *tty)
+{
+	raw3215_info *raw;
+
+	raw = (raw3215_info *) tty->driver_data;
+	raw->flags |= RAW3215_STOPPED;
+}
+
+/*
+ * Enable writing to a 3215 tty
+ */
+static void tty3215_start(struct tty_struct *tty)
+{
+	raw3215_info *raw;
+	unsigned long flags;
+
+	raw = (raw3215_info *) tty->driver_data;
+	if (raw->flags & RAW3215_STOPPED) {
+		s390irq_spin_lock_irqsave(raw->irq, flags);
+		raw->flags &= ~RAW3215_STOPPED;
+		raw3215_try_io(raw);
+		s390irq_spin_unlock_irqrestore(raw->irq, flags);
+	}
+}
+
+/*
+ * 3215 console driver boottime initialization code.
+ * Register console. We can't request the IRQ here, because
+ * it's too early (kmalloc isn't working yet). We'll have to
+ * buffer all the console requests until we can request the
+ * irq. For this purpose we use some pages of fixed memory.
+ */
+void __init con3215_init(void)
+{
+	raw3215_info *raw;
+	raw3215_req *req;
+	int i;
+
+	if (!MACHINE_IS_VM && !MACHINE_IS_P390)
+                return;
+        if (MACHINE_IS_VM) {
+	        cpcmd("TERM CONMODE 3215", NULL, 0);
+	        cpcmd("TERM AUTOCR OFF", NULL, 0);
+        }
+
+	/* allocate 3215 request structures */
+	raw3215_freelist = NULL;
+	spin_lock_init(&raw3215_freelist_lock);
+	for (i = 0; i < NR_3215_REQ; i++) {
+		req = (raw3215_req *) alloc_bootmem(sizeof(raw3215_req));
+		req->next = raw3215_freelist;
+		raw3215_freelist = req;
+	}
+
+#ifdef CONFIG_3215_CONSOLE
+	raw3215[0] = raw = (raw3215_info *) 
+		alloc_bootmem(sizeof(raw3215_info));
+	memset(raw, 0, sizeof(raw3215_info));
+	raw->buffer = (char *) alloc_bootmem(RAW3215_BUFFER_SIZE);
+	raw->inbuf = (char *) alloc_bootmem(RAW3215_INBUF_SIZE);
+	/* Find the first console */
+	raw->irq = raw3215_find_dev(0);
+	raw->flags |= RAW3215_FIXED;
+	raw->tqueue.routine = raw3215_softint;
+	raw->tqueue.data = raw;
+        init_waitqueue_head(&raw->empty_wait);
+
+	if (raw->irq != -1) {
+		register_console(&con3215);
+		s390irq_spin_lock(raw->irq);
+		set_cons_dev(raw->irq);
+		s390irq_spin_unlock(raw->irq);
+	} else {
+		free_bootmem((unsigned long) raw->inbuf, RAW3215_INBUF_SIZE);
+		free_bootmem((unsigned long) raw->buffer, RAW3215_BUFFER_SIZE);
+		free_bootmem((unsigned long) raw, sizeof(raw3215_info));
+		raw3215[0] = NULL;
+		printk("Couldn't find a 3215 console device\n");
+	}
+#endif
+
+	/*
+	 * Initialize the tty_driver structure
+	 * Entries in tty3215_driver that are NOT initialized:
+	 * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
+	 */
+
+	memset(&tty3215_driver, 0, sizeof(struct tty_driver));
+	tty3215_driver.magic = TTY_DRIVER_MAGIC;
+	tty3215_driver.driver_name = "tty3215";
+	tty3215_driver.name = "ttyS";
+	tty3215_driver.name_base = 0;
+	tty3215_driver.major = TTY_MAJOR;
+	tty3215_driver.minor_start = 64;
+	tty3215_driver.num = NR_3215;
+	tty3215_driver.type = TTY_DRIVER_TYPE_SYSTEM;
+	tty3215_driver.subtype = SYSTEM_TYPE_TTY;
+	tty3215_driver.init_termios = tty_std_termios;
+	tty3215_driver.init_termios.c_iflag = IGNBRK | IGNPAR;
+	tty3215_driver.init_termios.c_oflag = ONLCR;
+	tty3215_driver.init_termios.c_lflag = ISIG;
+	tty3215_driver.flags = TTY_DRIVER_REAL_RAW;
+	tty3215_driver.refcount = &tty3215_refcount;
+	tty3215_driver.table = tty3215_table;
+	tty3215_driver.termios = tty3215_termios;
+	tty3215_driver.termios_locked = tty3215_termios_locked;
+
+	tty3215_driver.open = tty3215_open;
+	tty3215_driver.close = tty3215_close;
+	tty3215_driver.write = tty3215_write;
+	tty3215_driver.put_char = tty3215_put_char;
+	tty3215_driver.flush_chars = tty3215_flush_chars;
+	tty3215_driver.write_room = tty3215_write_room;
+	tty3215_driver.chars_in_buffer = tty3215_chars_in_buffer;
+	tty3215_driver.flush_buffer = tty3215_flush_buffer;
+	tty3215_driver.ioctl = tty3215_ioctl;
+	tty3215_driver.throttle = tty3215_throttle;
+	tty3215_driver.unthrottle = tty3215_unthrottle;
+	tty3215_driver.send_xchar = NULL;
+	tty3215_driver.set_termios = NULL;
+	tty3215_driver.stop = tty3215_stop;
+	tty3215_driver.start = tty3215_start;
+	tty3215_driver.hangup = NULL;
+	tty3215_driver.break_ctl = NULL;
+	tty3215_driver.wait_until_sent = NULL;
+	tty3215_driver.read_proc = NULL;
+
+	if (tty_register_driver(&tty3215_driver))
+		panic("Couldn't register tty3215 driver\n");
+
+}

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)