--- /dev/null
+/*
+ * SCLP VT220 terminal driver.
+ *
+ * Copyright IBM Corp. 2003, 2009
+ *
+ * Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com>
+ */
+
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/timer.h>
+#include <linux/kernel.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/major.h>
+#include <linux/console.h>
+#include <linux/kdev_t.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+
+#include <asm/uaccess.h>
+#include "sclp.h"
+
+#define SCLP_VT220_MAJOR TTY_MAJOR
+#define SCLP_VT220_MINOR 65
+#define SCLP_VT220_DRIVER_NAME "sclp_vt220"
+#define SCLP_VT220_DEVICE_NAME "ttysclp"
+#define SCLP_VT220_CONSOLE_NAME "ttyS"
+#define SCLP_VT220_CONSOLE_INDEX 1 /* console=ttyS1 */
+
+/* Representation of a single write request */
+struct sclp_vt220_request {
+ struct list_head list;
+ struct sclp_req sclp_req;
+ int retry_count;
+};
+
+/* VT220 SCCB */
+struct sclp_vt220_sccb {
+ struct sccb_header header;
+ struct evbuf_header evbuf;
+};
+
+#define SCLP_VT220_MAX_CHARS_PER_BUFFER (PAGE_SIZE - \
+ sizeof(struct sclp_vt220_request) - \
+ sizeof(struct sclp_vt220_sccb))
+
+/* Structures and data needed to register tty driver */
+static struct tty_driver *sclp_vt220_driver;
+
+static struct tty_port sclp_vt220_port;
+
+/* Lock to protect internal data from concurrent access */
+static spinlock_t sclp_vt220_lock;
+
+/* List of empty pages to be used as write request buffers */
+static struct list_head sclp_vt220_empty;
+
+/* List of pending requests */
+static struct list_head sclp_vt220_outqueue;
+
+/* Suspend mode flag */
+static int sclp_vt220_suspended;
+
+/* Flag that output queue is currently running */
+static int sclp_vt220_queue_running;
+
+/* Timer used for delaying write requests to merge subsequent messages into
+ * a single buffer */
+static struct timer_list sclp_vt220_timer;
+
+/* Pointer to current request buffer which has been partially filled but not
+ * yet sent */
+static struct sclp_vt220_request *sclp_vt220_current_request;
+
+/* Number of characters in current request buffer */
+static int sclp_vt220_buffered_chars;
+
+/* Counter controlling core driver initialization. */
+static int __initdata sclp_vt220_init_count;
+
+/* Flag indicating that sclp_vt220_current_request should really
+ * have been already queued but wasn't because the SCLP was processing
+ * another buffer */
+static int sclp_vt220_flush_later;
+
+static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf);
+static void sclp_vt220_pm_event_fn(struct sclp_register *reg,
+ enum sclp_pm_event sclp_pm_event);
+static int __sclp_vt220_emit(struct sclp_vt220_request *request);
+static void sclp_vt220_emit_current(void);
+
+/* Registration structure for SCLP output event buffers */
+static struct sclp_register sclp_vt220_register = {
+ .send_mask = EVTYP_VT220MSG_MASK,
+ .pm_event_fn = sclp_vt220_pm_event_fn,
+};
+
+/* Registration structure for SCLP input event buffers */
+static struct sclp_register sclp_vt220_register_input = {
+ .receive_mask = EVTYP_VT220MSG_MASK,
+ .receiver_fn = sclp_vt220_receiver_fn,
+};
+
+
+/*
+ * Put provided request buffer back into queue and check emit pending
+ * buffers if necessary.
+ */
+static void
+sclp_vt220_process_queue(struct sclp_vt220_request *request)
+{
+ unsigned long flags;
+ void *page;
+
+ do {
+ /* Put buffer back to list of empty buffers */
+ page = request->sclp_req.sccb;
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ /* Move request from outqueue to empty queue */
+ list_del(&request->list);
+ list_add_tail((struct list_head *) page, &sclp_vt220_empty);
+ /* Check if there is a pending buffer on the out queue. */
+ request = NULL;
+ if (!list_empty(&sclp_vt220_outqueue))
+ request = list_entry(sclp_vt220_outqueue.next,
+ struct sclp_vt220_request, list);
+ if (!request || sclp_vt220_suspended) {
+ sclp_vt220_queue_running = 0;
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ break;
+ }
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ } while (__sclp_vt220_emit(request));
+ if (request == NULL && sclp_vt220_flush_later)
+ sclp_vt220_emit_current();
+ tty_port_tty_wakeup(&sclp_vt220_port);
+}
+
+#define SCLP_BUFFER_MAX_RETRY 1
+
+/*
+ * Callback through which the result of a write request is reported by the
+ * SCLP.
+ */
+static void
+sclp_vt220_callback(struct sclp_req *request, void *data)
+{
+ struct sclp_vt220_request *vt220_request;
+ struct sclp_vt220_sccb *sccb;
+
+ vt220_request = (struct sclp_vt220_request *) data;
+ if (request->status == SCLP_REQ_FAILED) {
+ sclp_vt220_process_queue(vt220_request);
+ return;
+ }
+ sccb = (struct sclp_vt220_sccb *) vt220_request->sclp_req.sccb;
+
+ /* Check SCLP response code and choose suitable action */
+ switch (sccb->header.response_code) {
+ case 0x0020 :
+ break;
+
+ case 0x05f0: /* Target resource in improper state */
+ break;
+
+ case 0x0340: /* Contained SCLP equipment check */
+ if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY)
+ break;
+ /* Remove processed buffers and requeue rest */
+ if (sclp_remove_processed((struct sccb_header *) sccb) > 0) {
+ /* Not all buffers were processed */
+ sccb->header.response_code = 0x0000;
+ vt220_request->sclp_req.status = SCLP_REQ_FILLED;
+ if (sclp_add_request(request) == 0)
+ return;
+ }
+ break;
+
+ case 0x0040: /* SCLP equipment check */
+ if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY)
+ break;
+ sccb->header.response_code = 0x0000;
+ vt220_request->sclp_req.status = SCLP_REQ_FILLED;
+ if (sclp_add_request(request) == 0)
+ return;
+ break;
+
+ default:
+ break;
+ }
+ sclp_vt220_process_queue(vt220_request);
+}
+
+/*
+ * Emit vt220 request buffer to SCLP. Return zero on success, non-zero
+ * otherwise.
+ */
+static int
+__sclp_vt220_emit(struct sclp_vt220_request *request)
+{
+ request->sclp_req.command = SCLP_CMDW_WRITE_EVENT_DATA;
+ request->sclp_req.status = SCLP_REQ_FILLED;
+ request->sclp_req.callback = sclp_vt220_callback;
+ request->sclp_req.callback_data = (void *) request;
+
+ return sclp_add_request(&request->sclp_req);
+}
+
+/*
+ * Queue and emit current request.
+ */
+static void
+sclp_vt220_emit_current(void)
+{
+ unsigned long flags;
+ struct sclp_vt220_request *request;
+ struct sclp_vt220_sccb *sccb;
+
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ if (sclp_vt220_current_request) {
+ sccb = (struct sclp_vt220_sccb *)
+ sclp_vt220_current_request->sclp_req.sccb;
+ /* Only emit buffers with content */
+ if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) {
+ list_add_tail(&sclp_vt220_current_request->list,
+ &sclp_vt220_outqueue);
+ sclp_vt220_current_request = NULL;
+ if (timer_pending(&sclp_vt220_timer))
+ del_timer(&sclp_vt220_timer);
+ }
+ sclp_vt220_flush_later = 0;
+ }
+ if (sclp_vt220_queue_running || sclp_vt220_suspended)
+ goto out_unlock;
+ if (list_empty(&sclp_vt220_outqueue))
+ goto out_unlock;
+ request = list_first_entry(&sclp_vt220_outqueue,
+ struct sclp_vt220_request, list);
+ sclp_vt220_queue_running = 1;
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+
+ if (__sclp_vt220_emit(request))
+ sclp_vt220_process_queue(request);
+ return;
+out_unlock:
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+}
+
+#define SCLP_NORMAL_WRITE 0x00
+
+/*
+ * Helper function to initialize a page with the sclp request structure.
+ */
+static struct sclp_vt220_request *
+sclp_vt220_initialize_page(void *page)
+{
+ struct sclp_vt220_request *request;
+ struct sclp_vt220_sccb *sccb;
+
+ /* Place request structure at end of page */
+ request = ((struct sclp_vt220_request *)
+ ((addr_t) page + PAGE_SIZE)) - 1;
+ request->retry_count = 0;
+ request->sclp_req.sccb = page;
+ /* SCCB goes at start of page */
+ sccb = (struct sclp_vt220_sccb *) page;
+ memset((void *) sccb, 0, sizeof(struct sclp_vt220_sccb));
+ sccb->header.length = sizeof(struct sclp_vt220_sccb);
+ sccb->header.function_code = SCLP_NORMAL_WRITE;
+ sccb->header.response_code = 0x0000;
+ sccb->evbuf.type = EVTYP_VT220MSG;
+ sccb->evbuf.length = sizeof(struct evbuf_header);
+
+ return request;
+}
+
+static inline unsigned int
+sclp_vt220_space_left(struct sclp_vt220_request *request)
+{
+ struct sclp_vt220_sccb *sccb;
+ sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb;
+ return PAGE_SIZE - sizeof(struct sclp_vt220_request) -
+ sccb->header.length;
+}
+
+static inline unsigned int
+sclp_vt220_chars_stored(struct sclp_vt220_request *request)
+{
+ struct sclp_vt220_sccb *sccb;
+ sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb;
+ return sccb->evbuf.length - sizeof(struct evbuf_header);
+}
+
+/*
+ * Add msg to buffer associated with request. Return the number of characters
+ * added.
+ */
+static int
+sclp_vt220_add_msg(struct sclp_vt220_request *request,
+ const unsigned char *msg, int count, int convertlf)
+{
+ struct sclp_vt220_sccb *sccb;
+ void *buffer;
+ unsigned char c;
+ int from;
+ int to;
+
+ if (count > sclp_vt220_space_left(request))
+ count = sclp_vt220_space_left(request);
+ if (count <= 0)
+ return 0;
+
+ sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb;
+ buffer = (void *) ((addr_t) sccb + sccb->header.length);
+
+ if (convertlf) {
+ /* Perform Linefeed conversion (0x0a -> 0x0a 0x0d)*/
+ for (from=0, to=0;
+ (from < count) && (to < sclp_vt220_space_left(request));
+ from++) {
+ /* Retrieve character */
+ c = msg[from];
+ /* Perform conversion */
+ if (c == 0x0a) {
+ if (to + 1 < sclp_vt220_space_left(request)) {
+ ((unsigned char *) buffer)[to++] = c;
+ ((unsigned char *) buffer)[to++] = 0x0d;
+ } else
+ break;
+
+ } else
+ ((unsigned char *) buffer)[to++] = c;
+ }
+ sccb->header.length += to;
+ sccb->evbuf.length += to;
+ return from;
+ } else {
+ memcpy(buffer, (const void *) msg, count);
+ sccb->header.length += count;
+ sccb->evbuf.length += count;
+ return count;
+ }
+}
+
+/*
+ * Emit buffer after having waited long enough for more data to arrive.
+ */
+static void
+sclp_vt220_timeout(unsigned long data)
+{
+ sclp_vt220_emit_current();
+}
+
+#define BUFFER_MAX_DELAY HZ/20
+
+/*
+ * Drop oldest console buffer if sclp_con_drop is set
+ */
+static int
+sclp_vt220_drop_buffer(void)
+{
+ struct list_head *list;
+ struct sclp_vt220_request *request;
+ void *page;
+
+ if (!sclp_console_drop)
+ return 0;
+ list = sclp_vt220_outqueue.next;
+ if (sclp_vt220_queue_running)
+ /* The first element is in I/O */
+ list = list->next;
+ if (list == &sclp_vt220_outqueue)
+ return 0;
+ list_del(list);
+ request = list_entry(list, struct sclp_vt220_request, list);
+ page = request->sclp_req.sccb;
+ list_add_tail((struct list_head *) page, &sclp_vt220_empty);
+ return 1;
+}
+
+/*
+ * Internal implementation of the write function. Write COUNT bytes of data
+ * from memory at BUF
+ * to the SCLP interface. In case that the data does not fit into the current
+ * write buffer, emit the current one and allocate a new one. If there are no
+ * more empty buffers available, wait until one gets emptied. If DO_SCHEDULE
+ * is non-zero, the buffer will be scheduled for emitting after a timeout -
+ * otherwise the user has to explicitly call the flush function.
+ * A non-zero CONVERTLF parameter indicates that 0x0a characters in the message
+ * buffer should be converted to 0x0a 0x0d. After completion, return the number
+ * of bytes written.
+ */
+static int
+__sclp_vt220_write(const unsigned char *buf, int count, int do_schedule,
+ int convertlf, int may_fail)
+{
+ unsigned long flags;
+ void *page;
+ int written;
+ int overall_written;
+
+ if (count <= 0)
+ return 0;
+ overall_written = 0;
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ do {
+ /* Create an sclp output buffer if none exists yet */
+ if (sclp_vt220_current_request == NULL) {
+ if (list_empty(&sclp_vt220_empty))
+ sclp_console_full++;
+ while (list_empty(&sclp_vt220_empty)) {
+ if (may_fail || sclp_vt220_suspended)
+ goto out;
+ if (sclp_vt220_drop_buffer())
+ break;
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+
+ sclp_sync_wait();
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ }
+ page = (void *) sclp_vt220_empty.next;
+ list_del((struct list_head *) page);
+ sclp_vt220_current_request =
+ sclp_vt220_initialize_page(page);
+ }
+ /* Try to write the string to the current request buffer */
+ written = sclp_vt220_add_msg(sclp_vt220_current_request,
+ buf, count, convertlf);
+ overall_written += written;
+ if (written == count)
+ break;
+ /*
+ * Not all characters could be written to the current
+ * output buffer. Emit the buffer, create a new buffer
+ * and then output the rest of the string.
+ */
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ sclp_vt220_emit_current();
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ buf += written;
+ count -= written;
+ } while (count > 0);
+ /* Setup timer to output current console buffer after some time */
+ if (sclp_vt220_current_request != NULL &&
+ !timer_pending(&sclp_vt220_timer) && do_schedule) {
+ sclp_vt220_timer.function = sclp_vt220_timeout;
+ sclp_vt220_timer.data = 0UL;
+ sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY;
+ add_timer(&sclp_vt220_timer);
+ }
+out:
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ return overall_written;
+}
+
+/*
+ * This routine is called by the kernel to write a series of
+ * characters to the tty device. The characters may come from
+ * user space or kernel space. This routine will return the
+ * number of characters actually accepted for writing.
+ */
+static int
+sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count)
+{
+ return __sclp_vt220_write(buf, count, 1, 0, 1);
+}
+
+#define SCLP_VT220_SESSION_ENDED 0x01
+#define SCLP_VT220_SESSION_STARTED 0x80
+#define SCLP_VT220_SESSION_DATA 0x00
+
+/*
+ * Called by the SCLP to report incoming event buffers.
+ */
+static void
+sclp_vt220_receiver_fn(struct evbuf_header *evbuf)
+{
+ char *buffer;
+ unsigned int count;
+
+ buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header));
+ count = evbuf->length - sizeof(struct evbuf_header);
+
+ switch (*buffer) {
+ case SCLP_VT220_SESSION_ENDED:
+ case SCLP_VT220_SESSION_STARTED:
+ break;
+ case SCLP_VT220_SESSION_DATA:
+ /* Send input to line discipline */
+ buffer++;
+ count--;
+ tty_insert_flip_string(&sclp_vt220_port, buffer, count);
+ tty_flip_buffer_push(&sclp_vt220_port);
+ break;
+ }
+}
+
+/*
+ * This routine is called when a particular tty device is opened.
+ */
+static int
+sclp_vt220_open(struct tty_struct *tty, struct file *filp)
+{
+ if (tty->count == 1) {
+ tty_port_tty_set(&sclp_vt220_port, tty);
+ sclp_vt220_port.low_latency = 0;
+ if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
+ tty->winsize.ws_row = 24;
+ tty->winsize.ws_col = 80;
+ }
+ }
+ return 0;
+}
+
+/*
+ * This routine is called when a particular tty device is closed.
+ */
+static void
+sclp_vt220_close(struct tty_struct *tty, struct file *filp)
+{
+ if (tty->count == 1)
+ tty_port_tty_set(&sclp_vt220_port, NULL);
+}
+
+/*
+ * This routine is called by the kernel to write a single
+ * character to the tty device. If the kernel uses this routine,
+ * it must call the flush_chars() routine (if defined) when it is
+ * done stuffing characters into the driver.
+ */
+static int
+sclp_vt220_put_char(struct tty_struct *tty, unsigned char ch)
+{
+ return __sclp_vt220_write(&ch, 1, 0, 0, 1);
+}
+
+/*
+ * This routine is called by the kernel after it has written a
+ * series of characters to the tty device using put_char().
+ */
+static void
+sclp_vt220_flush_chars(struct tty_struct *tty)
+{
+ if (!sclp_vt220_queue_running)
+ sclp_vt220_emit_current();
+ else
+ sclp_vt220_flush_later = 1;
+}
+
+/*
+ * This routine returns the numbers of characters the tty driver
+ * will accept for queuing to be written. This number is subject
+ * to change as output buffers get emptied, or if the output flow
+ * control is acted.
+ */
+static int
+sclp_vt220_write_room(struct tty_struct *tty)
+{
+ unsigned long flags;
+ struct list_head *l;
+ int count;
+
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ count = 0;
+ if (sclp_vt220_current_request != NULL)
+ count = sclp_vt220_space_left(sclp_vt220_current_request);
+ list_for_each(l, &sclp_vt220_empty)
+ count += SCLP_VT220_MAX_CHARS_PER_BUFFER;
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ return count;
+}
+
+/*
+ * Return number of buffered chars.
+ */
+static int
+sclp_vt220_chars_in_buffer(struct tty_struct *tty)
+{
+ unsigned long flags;
+ struct list_head *l;
+ struct sclp_vt220_request *r;
+ int count;
+
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ count = 0;
+ if (sclp_vt220_current_request != NULL)
+ count = sclp_vt220_chars_stored(sclp_vt220_current_request);
+ list_for_each(l, &sclp_vt220_outqueue) {
+ r = list_entry(l, struct sclp_vt220_request, list);
+ count += sclp_vt220_chars_stored(r);
+ }
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ return count;
+}
+
+/*
+ * Pass on all buffers to the hardware. Return only when there are no more
+ * buffers pending.
+ */
+static void
+sclp_vt220_flush_buffer(struct tty_struct *tty)
+{
+ sclp_vt220_emit_current();
+}
+
+/* Release allocated pages. */
+static void __init __sclp_vt220_free_pages(void)
+{
+ struct list_head *page, *p;
+
+ list_for_each_safe(page, p, &sclp_vt220_empty) {
+ list_del(page);
+ free_page((unsigned long) page);
+ }
+}
+
+/* Release memory and unregister from sclp core. Controlled by init counting -
+ * only the last invoker will actually perform these actions. */
+static void __init __sclp_vt220_cleanup(void)
+{
+ sclp_vt220_init_count--;
+ if (sclp_vt220_init_count != 0)
+ return;
+ sclp_unregister(&sclp_vt220_register);
+ __sclp_vt220_free_pages();
+ tty_port_destroy(&sclp_vt220_port);
+}
+
+/* Allocate buffer pages and register with sclp core. Controlled by init
+ * counting - only the first invoker will actually perform these actions. */
+static int __init __sclp_vt220_init(int num_pages)
+{
+ void *page;
+ int i;
+ int rc;
+
+ sclp_vt220_init_count++;
+ if (sclp_vt220_init_count != 1)
+ return 0;
+ spin_lock_init(&sclp_vt220_lock);
+ INIT_LIST_HEAD(&sclp_vt220_empty);
+ INIT_LIST_HEAD(&sclp_vt220_outqueue);
+ init_timer(&sclp_vt220_timer);
+ tty_port_init(&sclp_vt220_port);
+ sclp_vt220_current_request = NULL;
+ sclp_vt220_buffered_chars = 0;
+ sclp_vt220_flush_later = 0;
+
+ /* Allocate pages for output buffering */
+ rc = -ENOMEM;
+ for (i = 0; i < num_pages; i++) {
+ page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ if (!page)
+ goto out;
+ list_add_tail(page, &sclp_vt220_empty);
+ }
+ rc = sclp_register(&sclp_vt220_register);
+out:
+ if (rc) {
+ __sclp_vt220_free_pages();
+ sclp_vt220_init_count--;
+ tty_port_destroy(&sclp_vt220_port);
+ }
+ return rc;
+}
+
+static const struct tty_operations sclp_vt220_ops = {
+ .open = sclp_vt220_open,
+ .close = sclp_vt220_close,
+ .write = sclp_vt220_write,
+ .put_char = sclp_vt220_put_char,
+ .flush_chars = sclp_vt220_flush_chars,
+ .write_room = sclp_vt220_write_room,
+ .chars_in_buffer = sclp_vt220_chars_in_buffer,
+ .flush_buffer = sclp_vt220_flush_buffer,
+};
+
+/*
+ * Register driver with SCLP and Linux and initialize internal tty structures.
+ */
+static int __init sclp_vt220_tty_init(void)
+{
+ struct tty_driver *driver;
+ int rc;
+
+ /* Note: we're not testing for CONSOLE_IS_SCLP here to preserve
+ * symmetry between VM and LPAR systems regarding ttyS1. */
+ driver = alloc_tty_driver(1);
+ if (!driver)
+ return -ENOMEM;
+ rc = __sclp_vt220_init(MAX_KMEM_PAGES);
+ if (rc)
+ goto out_driver;
+
+ driver->driver_name = SCLP_VT220_DRIVER_NAME;
+ driver->name = SCLP_VT220_DEVICE_NAME;
+ driver->major = SCLP_VT220_MAJOR;
+ driver->minor_start = SCLP_VT220_MINOR;
+ driver->type = TTY_DRIVER_TYPE_SYSTEM;
+ driver->subtype = SYSTEM_TYPE_TTY;
+ driver->init_termios = tty_std_termios;
+ driver->flags = TTY_DRIVER_REAL_RAW;
+ tty_set_operations(driver, &sclp_vt220_ops);
+ tty_port_link_device(&sclp_vt220_port, driver, 0);
+
+ rc = tty_register_driver(driver);
+ if (rc)
+ goto out_init;
+ rc = sclp_register(&sclp_vt220_register_input);
+ if (rc)
+ goto out_reg;
+ sclp_vt220_driver = driver;
+ return 0;
+
+out_reg:
+ tty_unregister_driver(driver);
+out_init:
+ __sclp_vt220_cleanup();
+out_driver:
+ put_tty_driver(driver);
+ return rc;
+}
+__initcall(sclp_vt220_tty_init);
+
+static void __sclp_vt220_flush_buffer(void)
+{
+ unsigned long flags;
+
+ sclp_vt220_emit_current();
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ if (timer_pending(&sclp_vt220_timer))
+ del_timer(&sclp_vt220_timer);
+ while (sclp_vt220_queue_running) {
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ sclp_sync_wait();
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ }
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+}
+
+/*
+ * Resume console: If there are cached messages, emit them.
+ */
+static void sclp_vt220_resume(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ sclp_vt220_suspended = 0;
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ sclp_vt220_emit_current();
+}
+
+/*
+ * Suspend console: Set suspend flag and flush console
+ */
+static void sclp_vt220_suspend(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&sclp_vt220_lock, flags);
+ sclp_vt220_suspended = 1;
+ spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+ __sclp_vt220_flush_buffer();
+}
+
+static void sclp_vt220_pm_event_fn(struct sclp_register *reg,
+ enum sclp_pm_event sclp_pm_event)
+{
+ switch (sclp_pm_event) {
+ case SCLP_PM_EVENT_FREEZE:
+ sclp_vt220_suspend();
+ break;
+ case SCLP_PM_EVENT_RESTORE:
+ case SCLP_PM_EVENT_THAW:
+ sclp_vt220_resume();
+ break;
+ }
+}
+
+#ifdef CONFIG_SCLP_VT220_CONSOLE
+
+static void
+sclp_vt220_con_write(struct console *con, const char *buf, unsigned int count)
+{
+ __sclp_vt220_write((const unsigned char *) buf, count, 1, 1, 0);
+}
+
+static struct tty_driver *
+sclp_vt220_con_device(struct console *c, int *index)
+{
+ *index = 0;
+ return sclp_vt220_driver;
+}
+
+static int
+sclp_vt220_notify(struct notifier_block *self,
+ unsigned long event, void *data)
+{
+ __sclp_vt220_flush_buffer();
+ return NOTIFY_OK;
+}
+
+static struct notifier_block on_panic_nb = {
+ .notifier_call = sclp_vt220_notify,
+ .priority = 1,
+};
+
+static struct notifier_block on_reboot_nb = {
+ .notifier_call = sclp_vt220_notify,
+ .priority = 1,
+};
+
+/* Structure needed to register with printk */
+static struct console sclp_vt220_console =
+{
+ .name = SCLP_VT220_CONSOLE_NAME,
+ .write = sclp_vt220_con_write,
+ .device = sclp_vt220_con_device,
+ .flags = CON_PRINTBUFFER,
+ .index = SCLP_VT220_CONSOLE_INDEX
+};
+
+static int __init
+sclp_vt220_con_init(void)
+{
+ int rc;
+
+ rc = __sclp_vt220_init(sclp_console_pages);
+ if (rc)
+ return rc;
+ /* Attach linux console */
+ atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
+ register_reboot_notifier(&on_reboot_nb);
+ register_console(&sclp_vt220_console);
+ return 0;
+}
+
+console_initcall(sclp_vt220_con_init);
+#endif /* CONFIG_SCLP_VT220_CONSOLE */
+
Code Review / kvmfornfv.git / blobdiff