384 lines
13 KiB
C
384 lines
13 KiB
C
/* This file contains the printer driver. It is a fairly simple driver,
|
|
* supporting only one printer. Characters that are written to the driver
|
|
* are written to the printer without any changes at all.
|
|
*
|
|
* Changes:
|
|
* May 07, 2004 wait until printer is ready (Jorrit N. Herder)
|
|
* May 06, 2004 printer driver moved to user-space (Jorrit N. Herder)
|
|
*
|
|
* The valid messages and their parameters are:
|
|
*
|
|
* DEV_OPEN: initializes the printer
|
|
* DEV_CLOSE: does nothing
|
|
* HARD_INT: interrupt handler has finished current chunk of output
|
|
* DEV_WRITE: a process wants to write on a terminal
|
|
* CANCEL: terminate a previous incomplete system call immediately
|
|
*
|
|
* m_type TTY_LINE PROC_NR COUNT ADDRESS
|
|
* |-------------+---------+---------+---------+---------|
|
|
* | DEV_OPEN | | | | |
|
|
* |-------------+---------+---------+---------+---------|
|
|
* | DEV_CLOSE | | proc nr | | |
|
|
* -------------------------------------------------------
|
|
* | HARD_INT | | | | |
|
|
* |-------------+---------+---------+---------+---------|
|
|
* | HARD_STOP | | | | |
|
|
* |-------------+---------+---------+---------+---------|
|
|
* | DEV_WRITE |minor dev| proc nr | count | buf ptr |
|
|
* |-------------+---------+---------+---------+---------|
|
|
* | CANCEL |minor dev| proc nr | | |
|
|
* -------------------------------------------------------
|
|
*
|
|
* Note: since only 1 printer is supported, minor dev is not used at present.
|
|
*/
|
|
|
|
#include "../drivers.h"
|
|
|
|
#if ENABLE_PRINTER
|
|
|
|
/* Control bits (in port_base + 2). "+" means positive logic and "-" means
|
|
* negative logic. Most of the signals are negative logic on the pins but
|
|
* many are converted to positive logic in the ports. Some manuals are
|
|
* misleading because they only document the pin logic.
|
|
*
|
|
* +0x01 Pin 1 -Strobe
|
|
* +0x02 Pin 14 -Auto Feed
|
|
* -0x04 Pin 16 -Initialize Printer
|
|
* +0x08 Pin 17 -Select Printer
|
|
* +0x10 IRQ7 Enable
|
|
*
|
|
* Auto Feed and Select Printer are always enabled. Strobe is enabled briefly
|
|
* when characters are output. Initialize Printer is enabled briefly when
|
|
* the task is started. IRQ7 is enabled when the first character is output
|
|
* and left enabled until output is completed (or later after certain
|
|
* abnormal completions).
|
|
*/
|
|
#define ASSERT_STROBE 0x1D /* strobe a character to the interface */
|
|
#define NEGATE_STROBE 0x1C /* enable interrupt on interface */
|
|
#define SELECT 0x0C /* select printer bit */
|
|
#define INIT_PRINTER 0x08 /* init printer bits */
|
|
|
|
/* Status bits (in port_base + 2).
|
|
*
|
|
* -0x08 Pin 15 -Error
|
|
* +0x10 Pin 13 +Select Status
|
|
* +0x20 Pin 12 +Out of Paper
|
|
* -0x40 Pin 10 -Acknowledge
|
|
* -0x80 Pin 11 +Busy
|
|
*/
|
|
#define BUSY_STATUS 0x10 /* printer gives this status when busy */
|
|
#define NO_PAPER 0x20 /* status bit saying that paper is out */
|
|
#define NORMAL_STATUS 0x90 /* printer gives this status when idle */
|
|
#define ON_LINE 0x10 /* status bit saying that printer is online */
|
|
#define STATUS_MASK 0xB0 /* mask to filter out status bits */
|
|
|
|
#define MAX_ONLINE_RETRIES 120 /* about 60s: waits 0.5s after each retry */
|
|
|
|
/* Centronics interface timing that must be met by software (in microsec).
|
|
*
|
|
* Strobe length: 0.5u to 100u (not sure about the upper limit).
|
|
* Data set up: 0.5u before strobe.
|
|
* Data hold: 0.5u after strobe.
|
|
* Init pulse length: over 200u (not sure).
|
|
*
|
|
* The strobe length is about 50u with the code here and function calls for
|
|
* sys_outb() - not much to spare. The 0.5u minimums will not be violated
|
|
* with the sys_outb() messages exchanged.
|
|
*/
|
|
|
|
PRIVATE int caller; /* process to tell when printing done (FS) */
|
|
PRIVATE int done_status; /* status of last output completion */
|
|
PRIVATE int oleft; /* bytes of output left in obuf */
|
|
PRIVATE char obuf[128]; /* output buffer */
|
|
PRIVATE char *optr; /* ptr to next char in obuf to print */
|
|
PRIVATE int orig_count; /* original byte count */
|
|
PRIVATE int port_base; /* I/O port for printer */
|
|
PRIVATE int proc_nr; /* user requesting the printing */
|
|
PRIVATE int user_left; /* bytes of output left in user buf */
|
|
PRIVATE vir_bytes user_vir; /* address of remainder of user buf */
|
|
PRIVATE int writing; /* nonzero while write is in progress */
|
|
|
|
FORWARD _PROTOTYPE( void do_cancel, (message *m_ptr) );
|
|
FORWARD _PROTOTYPE( void output_done, (void) );
|
|
FORWARD _PROTOTYPE( void do_write, (message *m_ptr) );
|
|
FORWARD _PROTOTYPE( void prepare_output, (void) );
|
|
FORWARD _PROTOTYPE( void do_initialize, (void) );
|
|
FORWARD _PROTOTYPE( void reply, (int code,int replyee,int proc,int status));
|
|
FORWARD _PROTOTYPE( void do_printer_output, (void) );
|
|
|
|
/*===========================================================================*
|
|
* printer_task *
|
|
*===========================================================================*/
|
|
PUBLIC void main(void)
|
|
{
|
|
/* Main routine of the printer task. */
|
|
|
|
message pr_mess; /* buffer for all incoming messages */
|
|
|
|
printf("PRN: user-level printer driver is up and running\n");
|
|
|
|
while (TRUE) {
|
|
receive(ANY, &pr_mess);
|
|
switch(pr_mess.m_type) {
|
|
case DEV_OPEN:
|
|
do_initialize(); /* initialize */
|
|
/* fall through */
|
|
case DEV_CLOSE:
|
|
reply(TASK_REPLY, pr_mess.m_source, pr_mess.PROC_NR, OK);
|
|
break;
|
|
case DEV_WRITE: do_write(&pr_mess); break;
|
|
case CANCEL : do_cancel(&pr_mess); break;
|
|
case HARD_INT : do_printer_output(); break;
|
|
case HARD_STOP: sys_exit(0);
|
|
/* never reached */
|
|
break;
|
|
default:
|
|
reply(TASK_REPLY, pr_mess.m_source, pr_mess.PROC_NR, EINVAL);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* do_write *
|
|
*===========================================================================*/
|
|
PRIVATE void do_write(m_ptr)
|
|
register message *m_ptr; /* pointer to the newly arrived message */
|
|
{
|
|
/* The printer is used by sending DEV_WRITE messages to it. Process one. */
|
|
|
|
register int r = SUSPEND;
|
|
int retries;
|
|
int status;
|
|
|
|
/* Reject command if last write is not yet finished, the count is not
|
|
* positive, or the user address is bad.
|
|
*/
|
|
if (writing) r = EIO;
|
|
else if (m_ptr->COUNT <= 0) r = EINVAL;
|
|
|
|
/* Reply to FS, no matter what happened, possible SUSPEND caller. */
|
|
reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, r);
|
|
|
|
/* If no errors occurred, continue printing with SUSPENDED caller.
|
|
* First wait until the printer is online to prevent stupid errors.
|
|
*/
|
|
if (SUSPEND == r) {
|
|
caller = m_ptr->m_source;
|
|
proc_nr = m_ptr->PROC_NR;
|
|
user_left = m_ptr->COUNT;
|
|
orig_count = m_ptr->COUNT;
|
|
user_vir = (vir_bytes) m_ptr->ADDRESS;
|
|
writing = TRUE;
|
|
|
|
retries = MAX_ONLINE_RETRIES + 1;
|
|
while (--retries > 0) {
|
|
sys_inb(port_base + 1, &status);
|
|
if ((status & ON_LINE)) { /* printer online! */
|
|
prepare_output();
|
|
do_printer_output();
|
|
return;
|
|
}
|
|
tick_delay(30); /* wait before retry */
|
|
}
|
|
/* If we reach this point, the printer was not online in time. */
|
|
done_status = status;
|
|
output_done();
|
|
}
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* output_done *
|
|
*===========================================================================*/
|
|
PRIVATE void output_done()
|
|
{
|
|
/* Previous chunk of printing is finished. Continue if OK and more.
|
|
* Otherwise, reply to caller (FS).
|
|
*/
|
|
register int status;
|
|
|
|
if (!writing) return; /* probably leftover interrupt */
|
|
if (done_status != OK) { /* printer error occurred */
|
|
status = EIO;
|
|
if ((done_status & ON_LINE) == 0) {
|
|
printf("Printer is not on line\n");
|
|
} else if ((done_status & NO_PAPER)) {
|
|
printf("Printer is out of paper\n");
|
|
status = EAGAIN;
|
|
} else {
|
|
printf("Printer error, status is 0x%02X\n", done_status);
|
|
}
|
|
/* Some characters have been printed, tell how many. */
|
|
if (status == EAGAIN && user_left < orig_count) {
|
|
status = orig_count - user_left;
|
|
}
|
|
oleft = 0; /* cancel further output */
|
|
}
|
|
else if (user_left != 0) { /* not yet done, continue! */
|
|
prepare_output();
|
|
return;
|
|
}
|
|
else { /* done! report back to FS */
|
|
status = orig_count;
|
|
}
|
|
reply(REVIVE, caller, proc_nr, status);
|
|
writing = FALSE;
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* do_cancel *
|
|
*===========================================================================*/
|
|
PRIVATE void do_cancel(m_ptr)
|
|
register message *m_ptr; /* pointer to the newly arrived message */
|
|
{
|
|
/* Cancel a print request that has already started. Usually this means that
|
|
* the process doing the printing has been killed by a signal. It is not
|
|
* clear if there are race conditions. Try not to cancel the wrong process,
|
|
* but rely on FS to handle the EINTR reply and de-suspension properly.
|
|
*/
|
|
|
|
if (writing && m_ptr->PROC_NR == proc_nr) {
|
|
oleft = 0; /* cancel output by interrupt handler */
|
|
writing = FALSE;
|
|
}
|
|
reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, EINTR);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* reply *
|
|
*===========================================================================*/
|
|
PRIVATE void reply(code, replyee, process, status)
|
|
int code; /* TASK_REPLY or REVIVE */
|
|
int replyee; /* destination for message (normally FS) */
|
|
int process; /* which user requested the printing */
|
|
int status; /* number of chars printed or error code */
|
|
{
|
|
/* Send a reply telling FS that printing has started or stopped. */
|
|
|
|
message pr_mess;
|
|
|
|
pr_mess.m_type = code; /* TASK_REPLY or REVIVE */
|
|
pr_mess.REP_STATUS = status; /* count or EIO */
|
|
pr_mess.REP_PROC_NR = process; /* which user does this pertain to */
|
|
send(replyee, &pr_mess); /* send the message */
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* do_initialize *
|
|
*===========================================================================*/
|
|
PRIVATE void do_initialize()
|
|
{
|
|
/* Set global variables and initialize the printer. */
|
|
|
|
static int initialized = FALSE;
|
|
if (initialized) return;
|
|
initialized = TRUE;
|
|
|
|
/* Get the base port for first printer. This used to be done from the
|
|
* BIOS with phys_copy(0x408L, vir2phys(&port_base), 2L); but currently
|
|
* a magic number is put in place.
|
|
*/
|
|
port_base = 0x378;
|
|
sys_outb(port_base + 2, INIT_PRINTER);
|
|
tick_delay(1); /* easily satisfies Centronics minimum */
|
|
/* was 2 millisecs; now is ~17 millisecs */
|
|
sys_outb(port_base + 2, SELECT);
|
|
sys_irqsetpolicy(PRINTER_IRQ, SELF, 0, 0, 0, 0);
|
|
sys_irqenable(PRINTER_IRQ);
|
|
|
|
}
|
|
|
|
|
|
/*==========================================================================*
|
|
* prepare_output *
|
|
*==========================================================================*/
|
|
PRIVATE void prepare_output()
|
|
{
|
|
/* Start next chunk of printer output. Fetch the data from user space. */
|
|
|
|
register int chunk;
|
|
|
|
if ( (chunk = user_left) > sizeof obuf) chunk = sizeof obuf;
|
|
if (OK!=sys_datacopy(proc_nr, user_vir, SELF, (vir_bytes) obuf, chunk)) {
|
|
done_status = EFAULT;
|
|
output_done();
|
|
return;
|
|
}
|
|
optr = obuf;
|
|
oleft = chunk;
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* do_printer_output *
|
|
*===========================================================================*/
|
|
PRIVATE void do_printer_output()
|
|
{
|
|
/* This function does the actual output to the printer. This is called on
|
|
* a HARD_INT message sent from the generic interrupt handler that 'forwards'
|
|
* interrupts to this driver. The generic handler did not reenable the
|
|
* printer IRQ yet!
|
|
*/
|
|
|
|
int status;
|
|
pvb_pair_t char_out[3];
|
|
|
|
if (oleft == 0) {
|
|
/* Nothing more to print. Turn off printer interrupts in case they
|
|
* are level-sensitive as on the PS/2. This should be safe even
|
|
* when the printer is busy with a previous character, because the
|
|
* interrupt status does not affect the printer.
|
|
*/
|
|
sys_outb(port_base + 2, SELECT);
|
|
sys_irqenable(PRINTER_IRQ);
|
|
return;
|
|
}
|
|
|
|
do {
|
|
/* Loop to handle fast (buffered) printers. It is important that
|
|
* processor interrupts are not disabled here, just printer interrupts.
|
|
*/
|
|
(void) sys_inb(port_base + 1, &status);
|
|
if ((status & STATUS_MASK) == BUSY_STATUS) {
|
|
/* Still busy with last output. This normally happens
|
|
* immediately after doing output to an unbuffered or slow
|
|
* printer. It may happen after a call from prepare_output or
|
|
* pr_restart, since they are not synchronized with printer
|
|
* interrupts. It may happen after a spurious interrupt.
|
|
*/
|
|
sys_irqenable(PRINTER_IRQ);
|
|
return;
|
|
}
|
|
if ((status & STATUS_MASK) == NORMAL_STATUS) {
|
|
/* Everything is all right. Output another character. */
|
|
pv_set(char_out[0], port_base, *optr++);
|
|
pv_set(char_out[1], port_base+2, ASSERT_STROBE);
|
|
pv_set(char_out[2], port_base+2, NEGATE_STROBE);
|
|
sys_voutb(char_out, 3); /* request series of port outb */
|
|
|
|
user_vir++;
|
|
user_left--;
|
|
} else {
|
|
/* Error. This would be better ignored (treat as busy). */
|
|
done_status = status;
|
|
output_done();
|
|
sys_irqenable(PRINTER_IRQ);
|
|
return;
|
|
}
|
|
}
|
|
while (--oleft != 0);
|
|
|
|
/* Finished printing chunk OK. */
|
|
done_status = OK;
|
|
output_done();
|
|
sys_irqenable(PRINTER_IRQ);
|
|
}
|
|
|
|
|
|
#endif /* ENABLE_PRINTER */
|
|
|