846 строки
22 KiB
C
846 строки
22 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* SCLP VT220 terminal driver.
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*
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* Copyright IBM Corp. 2003, 2009
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*
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* Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com>
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*/
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <linux/panic_notifier.h>
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#include <linux/list.h>
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#include <linux/wait.h>
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#include <linux/timer.h>
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#include <linux/kernel.h>
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#include <linux/sysrq.h>
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#include <linux/tty.h>
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#include <linux/tty_driver.h>
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#include <linux/tty_flip.h>
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#include <linux/errno.h>
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#include <linux/mm.h>
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#include <linux/major.h>
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#include <linux/console.h>
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#include <linux/kdev_t.h>
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#include <linux/interrupt.h>
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#include <linux/init.h>
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#include <linux/reboot.h>
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#include <linux/slab.h>
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#include <linux/uaccess.h>
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#include "sclp.h"
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#include "ctrlchar.h"
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#define SCLP_VT220_MAJOR TTY_MAJOR
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#define SCLP_VT220_MINOR 65
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#define SCLP_VT220_DRIVER_NAME "sclp_vt220"
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#define SCLP_VT220_DEVICE_NAME "ttysclp"
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#define SCLP_VT220_CONSOLE_NAME "ttysclp"
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#define SCLP_VT220_CONSOLE_INDEX 0 /* console=ttysclp0 */
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/* Representation of a single write request */
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struct sclp_vt220_request {
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struct list_head list;
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struct sclp_req sclp_req;
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int retry_count;
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};
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/* VT220 SCCB */
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struct sclp_vt220_sccb {
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struct sccb_header header;
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struct evbuf_header evbuf;
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};
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#define SCLP_VT220_MAX_CHARS_PER_BUFFER (PAGE_SIZE - \
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sizeof(struct sclp_vt220_request) - \
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sizeof(struct sclp_vt220_sccb))
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/* Structures and data needed to register tty driver */
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static struct tty_driver *sclp_vt220_driver;
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static struct tty_port sclp_vt220_port;
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/* Lock to protect internal data from concurrent access */
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static DEFINE_SPINLOCK(sclp_vt220_lock);
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/* List of empty pages to be used as write request buffers */
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static LIST_HEAD(sclp_vt220_empty);
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/* List of pending requests */
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static LIST_HEAD(sclp_vt220_outqueue);
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/* Flag that output queue is currently running */
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static int sclp_vt220_queue_running;
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/* Timer used for delaying write requests to merge subsequent messages into
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* a single buffer */
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static struct timer_list sclp_vt220_timer;
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/* Pointer to current request buffer which has been partially filled but not
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* yet sent */
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static struct sclp_vt220_request *sclp_vt220_current_request;
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/* Number of characters in current request buffer */
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static int sclp_vt220_buffered_chars;
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/* Counter controlling core driver initialization. */
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static int __initdata sclp_vt220_init_count;
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/* Flag indicating that sclp_vt220_current_request should really
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* have been already queued but wasn't because the SCLP was processing
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* another buffer */
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static int sclp_vt220_flush_later;
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static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf);
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static int __sclp_vt220_emit(struct sclp_vt220_request *request);
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static void sclp_vt220_emit_current(void);
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/* Registration structure for SCLP output event buffers */
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static struct sclp_register sclp_vt220_register = {
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.send_mask = EVTYP_VT220MSG_MASK,
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};
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/* Registration structure for SCLP input event buffers */
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static struct sclp_register sclp_vt220_register_input = {
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.receive_mask = EVTYP_VT220MSG_MASK,
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.receiver_fn = sclp_vt220_receiver_fn,
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};
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/*
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* Put provided request buffer back into queue and check emit pending
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* buffers if necessary.
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*/
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static void
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sclp_vt220_process_queue(struct sclp_vt220_request *request)
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{
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unsigned long flags;
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void *page;
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do {
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/* Put buffer back to list of empty buffers */
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page = request->sclp_req.sccb;
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spin_lock_irqsave(&sclp_vt220_lock, flags);
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/* Move request from outqueue to empty queue */
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list_del(&request->list);
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list_add_tail((struct list_head *) page, &sclp_vt220_empty);
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/* Check if there is a pending buffer on the out queue. */
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request = NULL;
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if (!list_empty(&sclp_vt220_outqueue))
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request = list_entry(sclp_vt220_outqueue.next,
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struct sclp_vt220_request, list);
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if (!request) {
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sclp_vt220_queue_running = 0;
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spin_unlock_irqrestore(&sclp_vt220_lock, flags);
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break;
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}
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spin_unlock_irqrestore(&sclp_vt220_lock, flags);
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} while (__sclp_vt220_emit(request));
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if (request == NULL && sclp_vt220_flush_later)
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sclp_vt220_emit_current();
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tty_port_tty_wakeup(&sclp_vt220_port);
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}
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#define SCLP_BUFFER_MAX_RETRY 1
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/*
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* Callback through which the result of a write request is reported by the
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* SCLP.
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*/
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static void
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sclp_vt220_callback(struct sclp_req *request, void *data)
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{
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struct sclp_vt220_request *vt220_request;
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struct sclp_vt220_sccb *sccb;
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vt220_request = (struct sclp_vt220_request *) data;
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if (request->status == SCLP_REQ_FAILED) {
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sclp_vt220_process_queue(vt220_request);
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return;
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}
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sccb = (struct sclp_vt220_sccb *) vt220_request->sclp_req.sccb;
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/* Check SCLP response code and choose suitable action */
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switch (sccb->header.response_code) {
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case 0x0020 :
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break;
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case 0x05f0: /* Target resource in improper state */
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break;
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case 0x0340: /* Contained SCLP equipment check */
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if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY)
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break;
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/* Remove processed buffers and requeue rest */
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if (sclp_remove_processed((struct sccb_header *) sccb) > 0) {
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/* Not all buffers were processed */
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sccb->header.response_code = 0x0000;
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vt220_request->sclp_req.status = SCLP_REQ_FILLED;
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if (sclp_add_request(request) == 0)
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return;
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}
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break;
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case 0x0040: /* SCLP equipment check */
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if (++vt220_request->retry_count > SCLP_BUFFER_MAX_RETRY)
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break;
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sccb->header.response_code = 0x0000;
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vt220_request->sclp_req.status = SCLP_REQ_FILLED;
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if (sclp_add_request(request) == 0)
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return;
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break;
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default:
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break;
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}
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sclp_vt220_process_queue(vt220_request);
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}
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/*
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* Emit vt220 request buffer to SCLP. Return zero on success, non-zero
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* otherwise.
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*/
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static int
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__sclp_vt220_emit(struct sclp_vt220_request *request)
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{
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request->sclp_req.command = SCLP_CMDW_WRITE_EVENT_DATA;
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request->sclp_req.status = SCLP_REQ_FILLED;
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request->sclp_req.callback = sclp_vt220_callback;
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request->sclp_req.callback_data = (void *) request;
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return sclp_add_request(&request->sclp_req);
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}
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/*
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* Queue and emit current request.
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*/
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static void
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sclp_vt220_emit_current(void)
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{
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unsigned long flags;
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struct sclp_vt220_request *request;
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struct sclp_vt220_sccb *sccb;
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spin_lock_irqsave(&sclp_vt220_lock, flags);
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if (sclp_vt220_current_request) {
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sccb = (struct sclp_vt220_sccb *)
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sclp_vt220_current_request->sclp_req.sccb;
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/* Only emit buffers with content */
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if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) {
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list_add_tail(&sclp_vt220_current_request->list,
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&sclp_vt220_outqueue);
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sclp_vt220_current_request = NULL;
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del_timer(&sclp_vt220_timer);
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}
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sclp_vt220_flush_later = 0;
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}
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if (sclp_vt220_queue_running)
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goto out_unlock;
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if (list_empty(&sclp_vt220_outqueue))
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goto out_unlock;
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request = list_first_entry(&sclp_vt220_outqueue,
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struct sclp_vt220_request, list);
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sclp_vt220_queue_running = 1;
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spin_unlock_irqrestore(&sclp_vt220_lock, flags);
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if (__sclp_vt220_emit(request))
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sclp_vt220_process_queue(request);
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return;
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out_unlock:
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spin_unlock_irqrestore(&sclp_vt220_lock, flags);
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}
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#define SCLP_NORMAL_WRITE 0x00
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/*
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* Helper function to initialize a page with the sclp request structure.
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*/
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static struct sclp_vt220_request *
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sclp_vt220_initialize_page(void *page)
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{
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struct sclp_vt220_request *request;
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struct sclp_vt220_sccb *sccb;
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/* Place request structure at end of page */
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request = ((struct sclp_vt220_request *)
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((addr_t) page + PAGE_SIZE)) - 1;
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request->retry_count = 0;
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request->sclp_req.sccb = page;
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/* SCCB goes at start of page */
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sccb = (struct sclp_vt220_sccb *) page;
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memset((void *) sccb, 0, sizeof(struct sclp_vt220_sccb));
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sccb->header.length = sizeof(struct sclp_vt220_sccb);
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sccb->header.function_code = SCLP_NORMAL_WRITE;
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sccb->header.response_code = 0x0000;
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sccb->evbuf.type = EVTYP_VT220MSG;
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sccb->evbuf.length = sizeof(struct evbuf_header);
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return request;
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}
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static inline unsigned int
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sclp_vt220_space_left(struct sclp_vt220_request *request)
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{
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struct sclp_vt220_sccb *sccb;
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sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb;
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return PAGE_SIZE - sizeof(struct sclp_vt220_request) -
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sccb->header.length;
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}
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static inline unsigned int
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sclp_vt220_chars_stored(struct sclp_vt220_request *request)
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{
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struct sclp_vt220_sccb *sccb;
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sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb;
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return sccb->evbuf.length - sizeof(struct evbuf_header);
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}
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/*
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* Add msg to buffer associated with request. Return the number of characters
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* added.
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*/
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static int
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sclp_vt220_add_msg(struct sclp_vt220_request *request,
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const unsigned char *msg, int count, int convertlf)
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{
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struct sclp_vt220_sccb *sccb;
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void *buffer;
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unsigned char c;
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int from;
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int to;
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if (count > sclp_vt220_space_left(request))
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count = sclp_vt220_space_left(request);
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if (count <= 0)
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return 0;
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sccb = (struct sclp_vt220_sccb *) request->sclp_req.sccb;
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buffer = (void *) ((addr_t) sccb + sccb->header.length);
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if (convertlf) {
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/* Perform Linefeed conversion (0x0a -> 0x0a 0x0d)*/
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for (from=0, to=0;
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(from < count) && (to < sclp_vt220_space_left(request));
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from++) {
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/* Retrieve character */
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c = msg[from];
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/* Perform conversion */
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if (c == 0x0a) {
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if (to + 1 < sclp_vt220_space_left(request)) {
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((unsigned char *) buffer)[to++] = c;
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((unsigned char *) buffer)[to++] = 0x0d;
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} else
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break;
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} else
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((unsigned char *) buffer)[to++] = c;
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}
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sccb->header.length += to;
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sccb->evbuf.length += to;
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return from;
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} else {
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memcpy(buffer, (const void *) msg, count);
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sccb->header.length += count;
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sccb->evbuf.length += count;
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return count;
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}
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}
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/*
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* Emit buffer after having waited long enough for more data to arrive.
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*/
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static void
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sclp_vt220_timeout(struct timer_list *unused)
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{
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sclp_vt220_emit_current();
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}
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#define BUFFER_MAX_DELAY HZ/20
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/*
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* Drop oldest console buffer if sclp_con_drop is set
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*/
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static int
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sclp_vt220_drop_buffer(void)
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{
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struct list_head *list;
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struct sclp_vt220_request *request;
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void *page;
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if (!sclp_console_drop)
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return 0;
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list = sclp_vt220_outqueue.next;
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if (sclp_vt220_queue_running)
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/* The first element is in I/O */
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list = list->next;
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if (list == &sclp_vt220_outqueue)
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return 0;
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list_del(list);
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request = list_entry(list, struct sclp_vt220_request, list);
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page = request->sclp_req.sccb;
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list_add_tail((struct list_head *) page, &sclp_vt220_empty);
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return 1;
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}
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/*
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* Internal implementation of the write function. Write COUNT bytes of data
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* from memory at BUF
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* to the SCLP interface. In case that the data does not fit into the current
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* write buffer, emit the current one and allocate a new one. If there are no
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* more empty buffers available, wait until one gets emptied. If DO_SCHEDULE
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* is non-zero, the buffer will be scheduled for emitting after a timeout -
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* otherwise the user has to explicitly call the flush function.
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* A non-zero CONVERTLF parameter indicates that 0x0a characters in the message
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* buffer should be converted to 0x0a 0x0d. After completion, return the number
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* of bytes written.
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*/
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static int
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__sclp_vt220_write(const unsigned char *buf, int count, int do_schedule,
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int convertlf, int may_fail)
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{
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unsigned long flags;
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void *page;
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int written;
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int overall_written;
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if (count <= 0)
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return 0;
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overall_written = 0;
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spin_lock_irqsave(&sclp_vt220_lock, flags);
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do {
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/* Create an sclp output buffer if none exists yet */
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if (sclp_vt220_current_request == NULL) {
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if (list_empty(&sclp_vt220_empty))
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sclp_console_full++;
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while (list_empty(&sclp_vt220_empty)) {
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if (may_fail)
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goto out;
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if (sclp_vt220_drop_buffer())
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break;
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spin_unlock_irqrestore(&sclp_vt220_lock, flags);
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sclp_sync_wait();
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spin_lock_irqsave(&sclp_vt220_lock, flags);
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}
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page = (void *) sclp_vt220_empty.next;
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list_del((struct list_head *) page);
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sclp_vt220_current_request =
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sclp_vt220_initialize_page(page);
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}
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/* Try to write the string to the current request buffer */
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written = sclp_vt220_add_msg(sclp_vt220_current_request,
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buf, count, convertlf);
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overall_written += written;
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if (written == count)
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break;
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/*
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* Not all characters could be written to the current
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* output buffer. Emit the buffer, create a new buffer
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* and then output the rest of the string.
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*/
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spin_unlock_irqrestore(&sclp_vt220_lock, flags);
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sclp_vt220_emit_current();
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spin_lock_irqsave(&sclp_vt220_lock, flags);
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buf += written;
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count -= written;
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} while (count > 0);
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/* Setup timer to output current console buffer after some time */
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if (sclp_vt220_current_request != NULL &&
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!timer_pending(&sclp_vt220_timer) && do_schedule) {
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sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY;
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add_timer(&sclp_vt220_timer);
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}
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out:
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spin_unlock_irqrestore(&sclp_vt220_lock, flags);
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return overall_written;
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}
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/*
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* This routine is called by the kernel to write a series of
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* characters to the tty device. The characters may come from
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* user space or kernel space. This routine will return the
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* number of characters actually accepted for writing.
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*/
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static int
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sclp_vt220_write(struct tty_struct *tty, const unsigned char *buf, int count)
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{
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return __sclp_vt220_write(buf, count, 1, 0, 1);
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}
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#define SCLP_VT220_SESSION_ENDED 0x01
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#define SCLP_VT220_SESSION_STARTED 0x80
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#define SCLP_VT220_SESSION_DATA 0x00
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#ifdef CONFIG_MAGIC_SYSRQ
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static int sysrq_pressed;
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static struct sysrq_work sysrq;
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static void sclp_vt220_reset_session(void)
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{
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sysrq_pressed = 0;
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}
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static void sclp_vt220_handle_input(const char *buffer, unsigned int count)
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{
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int i;
|
|
|
|
for (i = 0; i < count; i++) {
|
|
/* Handle magic sys request */
|
|
if (buffer[i] == ('O' ^ 0100)) { /* CTRL-O */
|
|
/*
|
|
* If pressed again, reset sysrq_pressed
|
|
* and flip CTRL-O character
|
|
*/
|
|
sysrq_pressed = !sysrq_pressed;
|
|
if (sysrq_pressed)
|
|
continue;
|
|
} else if (sysrq_pressed) {
|
|
sysrq.key = buffer[i];
|
|
schedule_sysrq_work(&sysrq);
|
|
sysrq_pressed = 0;
|
|
continue;
|
|
}
|
|
tty_insert_flip_char(&sclp_vt220_port, buffer[i], 0);
|
|
}
|
|
}
|
|
|
|
#else
|
|
|
|
static void sclp_vt220_reset_session(void)
|
|
{
|
|
}
|
|
|
|
static void sclp_vt220_handle_input(const char *buffer, unsigned int count)
|
|
{
|
|
tty_insert_flip_string(&sclp_vt220_port, buffer, count);
|
|
}
|
|
|
|
#endif
|
|
|
|
/*
|
|
* 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:
|
|
sclp_vt220_reset_session();
|
|
break;
|
|
case SCLP_VT220_SESSION_DATA:
|
|
/* Send input to line discipline */
|
|
buffer++;
|
|
count--;
|
|
sclp_vt220_handle_input(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);
|
|
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 unsigned int
|
|
sclp_vt220_write_room(struct tty_struct *tty)
|
|
{
|
|
unsigned long flags;
|
|
struct list_head *l;
|
|
unsigned 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 unsigned int
|
|
sclp_vt220_chars_in_buffer(struct tty_struct *tty)
|
|
{
|
|
unsigned long flags;
|
|
struct list_head *l;
|
|
struct sclp_vt220_request *r;
|
|
unsigned int count = 0;
|
|
|
|
spin_lock_irqsave(&sclp_vt220_lock, flags);
|
|
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;
|
|
timer_setup(&sclp_vt220_timer, sclp_vt220_timeout, 0);
|
|
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 = tty_alloc_driver(1, TTY_DRIVER_REAL_RAW);
|
|
if (IS_ERR(driver))
|
|
return PTR_ERR(driver);
|
|
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;
|
|
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:
|
|
tty_driver_kref_put(driver);
|
|
return rc;
|
|
}
|
|
__initcall(sclp_vt220_tty_init);
|
|
|
|
#ifdef CONFIG_SCLP_VT220_CONSOLE
|
|
|
|
static void __sclp_vt220_flush_buffer(void)
|
|
{
|
|
unsigned long flags;
|
|
|
|
sclp_vt220_emit_current();
|
|
spin_lock_irqsave(&sclp_vt220_lock, flags);
|
|
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);
|
|
}
|
|
|
|
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 */
|
|
|