/*      $NetBSD: kbd_zs.c,v 1.24 2022/09/25 21:30:29 thorpej Exp $      */

/*
* Copyright (c) 1992, 1993
*      The Regents of the University of California.  All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
*      This product includes software developed by the University of
*      California, Lawrence Berkeley Laboratory.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*      @(#)kbd.c       8.2 (Berkeley) 10/30/93
*/

/*
* /dev/kbd lower layer for sun keyboard off a zs channel.
* This driver uses kbdsun middle layer to hook up to /dev/kbd.
*/

/*
* Zilog Z8530 Dual UART driver (keyboard interface)
*
* This is the 8530 portion of the driver that will be attached to
* the "zsc" driver for a Sun keyboard.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kbd_zs.c,v 1.24 2022/09/25 21:30:29 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/signal.h>
#include <sys/signalvar.h>
#include <sys/time.h>
#include <sys/select.h>
#include <sys/syslog.h>

#include <dev/ic/z8530reg.h>
#include <machine/z8530var.h>
#include <dev/sun/vuid_event.h>
#include <dev/sun/event_var.h>
#include <dev/sun/kbd_reg.h>
#include <dev/sun/kbd_xlate.h>
#include <dev/sun/kbdvar.h>
#include <dev/sun/kbdsunvar.h>

#if NWSKBD > 0
void kbd_wskbd_attach(struct kbd_softc *k, int isconsole);
#endif

/****************************************************************
* Interface to the lower layer (zscc)
****************************************************************/

static void kbd_zs_rxint(struct zs_chanstate *);
static void kbd_zs_stint(struct zs_chanstate *, int);
static void kbd_zs_txint(struct zs_chanstate *);
static void kbd_zs_softint(struct zs_chanstate *);

struct zsops zsops_kbd = {
       kbd_zs_rxint,   /* receive char available */
       kbd_zs_stint,   /* external/status */
       kbd_zs_txint,   /* xmit buffer empty */
       kbd_zs_softint, /* process software interrupt */
};

static int      kbd_zs_match(device_t, cfdata_t, void *);
static void     kbd_zs_attach(device_t, device_t, void *);
static void     kbd_zs_write_data(struct kbd_sun_softc *, int);

CFATTACH_DECL_NEW(kbd_zs, sizeof(struct kbd_sun_softc),
   kbd_zs_match, kbd_zs_attach, NULL, NULL);

/* Fall-back baud rate */
int     kbd_zs_bps = KBD_DEFAULT_BPS;

/*
* kbd_zs_match: how is this zs channel configured?
*/
int
kbd_zs_match(device_t parent, cfdata_t cf, void *aux)
{
       struct zsc_attach_args *args = aux;

       /* Exact match required for keyboard. */
       if (cf->cf_loc[ZSCCF_CHANNEL] == args->channel)
               return 2;

       return 0;
}

void
kbd_zs_attach(device_t parent, device_t self, void *aux)
{
       struct kbd_sun_softc *k = device_private(self);
       struct zsc_softc *zsc = device_private(parent);
       struct zsc_attach_args *args = aux;
       struct zs_chanstate *cs;
       int channel;
       int reset, s;
       int bps;

       k->k_kbd.k_dev = self;

       /* provide upper layer with a link to the middle layer */
       k->k_kbd.k_ops = &kbd_ops_sun;

       /* provide middle layer with a link to the lower layer (i.e. us) */
       channel = args->channel;
       cs = zsc->zsc_cs[channel];
       cs->cs_private = k;
       cs->cs_ops = &zsops_kbd;
       k->k_cs = cs;
       k->k_write_data = kbd_zs_write_data;

       if ((bps = cs->cs_defspeed) == 0)
               bps = kbd_zs_bps;

       aprint_normal(": baud rate %d", bps);

       if ((args->hwflags & ZS_HWFLAG_CONSOLE_INPUT) != 0) {
               /*
                * Hookup ourselves as the console input channel
                */
               struct cons_channel *cc = kbd_cc_alloc(&k->k_kbd);

               if (cc == NULL)
                       return;

               cons_attach_input(cc, args->consdev);
               k->k_kbd.k_isconsole = 1;
               aprint_normal(" (console input)");
       }
       aprint_normal("\n");

       /* Initialize the speed, etc. */
       s = splzs();
       if (k->k_kbd.k_isconsole == 0) {
               /* Not the console; may need reset. */
               reset = (channel == 0) ?
                   ZSWR9_A_RESET : ZSWR9_B_RESET;
               zs_write_reg(cs, 9, reset);
       }
       /* These are OK as set by zscc: WR3, WR4, WR5 */
       /* We don't care about status interrupts. */
       cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_TIE;
       (void) zs_set_speed(cs, bps);
       zs_loadchannelregs(cs);
       splx(s);

       /* Do this before any calls to kbd_rint(). */
       kbd_xlate_init(&k->k_kbd.k_state);

       /* Magic sequence. */
       k->k_magic1 = KBD_L1;
       k->k_magic2 = KBD_A;
#if NWSKBD > 0
       kbd_wskbd_attach(&k->k_kbd, k->k_kbd.k_isconsole);
#endif
}

/*
* used by kbd_sun_start_tx();
*/
void
kbd_zs_write_data(struct kbd_sun_softc *k, int c)
{
       int s;

       /* Need splzs to avoid interruption of the delay. */
       s = splzs();
       zs_write_data(k->k_cs, c);
       splx(s);
}

static void
kbd_zs_rxint(struct zs_chanstate *cs)
{
       struct kbd_sun_softc *k;
       int put, put_next;
       uint8_t c, rr1;

       k = cs->cs_private;
       put = k->k_rbput;

       /*
        * First read the status, because reading the received char
        * destroys the status of this char.
        */
       rr1 = zs_read_reg(cs, 1);
       c = zs_read_data(cs);

       if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
               /* Clear the receive error. */
               zs_write_csr(cs, ZSWR0_RESET_ERRORS);
       }

       /*
        * Check NOW for a console abort sequence, so that we can
        * abort even when interrupts are locking up the machine.
        */
       if (k->k_magic1_down) {
               /* The last keycode was "MAGIC1" down. */
               k->k_magic1_down = 0;
               if (c == k->k_magic2) {
                       /* Magic "L1-A" sequence; enter debugger. */
                       if (k->k_kbd.k_isconsole) {
                               zs_abort(cs);
                               /* Debugger done.  Fake L1-up to finish it. */
                               c = k->k_magic1 | KBD_UP;
                       } else {
                               printf("%s: magic sequence, but not console\n",
                                   device_xname(k->k_kbd.k_dev));
                       }
               }
       }
       if (c == k->k_magic1) {
               k->k_magic1_down = 1;
       }

       k->k_rbuf[put] = (c << 8) | rr1;
       put_next = (put + 1) & KBD_RX_RING_MASK;

       /* Would overrun if increment makes (put==get). */
       if (put_next == k->k_rbget) {
               k->k_intr_flags |= INTR_RX_OVERRUN;
       } else {
               /* OK, really increment. */
               put = put_next;
       }

       /* Done reading. */
       k->k_rbput = put;

       /* Ask for softint() call. */
       cs->cs_softreq = 1;
}


static void
kbd_zs_txint(struct zs_chanstate *cs)
{
       struct kbd_sun_softc *k;

       k = cs->cs_private;
       zs_write_csr(cs, ZSWR0_RESET_TXINT);
       k->k_intr_flags |= INTR_TX_EMPTY;
       /* Ask for softint() call. */
       cs->cs_softreq = 1;
}


static void
kbd_zs_stint(struct zs_chanstate *cs, int force)
{
       struct kbd_sun_softc *k;
       uint8_t rr0;

       k = cs->cs_private;

       rr0 = zs_read_csr(cs);
       zs_write_csr(cs, ZSWR0_RESET_STATUS);

#if 0
       if (rr0 & ZSRR0_BREAK) {
               /* Keyboard unplugged? */
               zs_abort(cs);
               return;
       }
#endif

       /*
        * We have to accumulate status line changes here.
        * Otherwise, if we get multiple status interrupts
        * before the softint runs, we could fail to notice
        * some status line changes in the softint routine.
        * Fix from Bill Studenmund, October 1996.
        */
       cs->cs_rr0_delta |= (cs->cs_rr0 ^ rr0);
       cs->cs_rr0 = rr0;
       k->k_intr_flags |= INTR_ST_CHECK;

       /* Ask for softint() call. */
       cs->cs_softreq = 1;
}

/*
* Get input from the receive ring and pass it on.
* Note: this is called at splsoftclock()
*/
static void
kbd_zs_softint(struct zs_chanstate *cs)
{
       struct kbd_sun_softc *k;
       int get, c, s;
       int intr_flags;
       uint16_t ring_data;

       k = cs->cs_private;

       /* Atomically get and clear flags. */
       s = splzs();
       intr_flags = k->k_intr_flags;
       k->k_intr_flags = 0;

       /* Now lower to spltty for the rest. */
       (void)spltty();

       /*
        * Copy data from the receive ring to the event layer.
        */
       get = k->k_rbget;
       while (get != k->k_rbput) {
               ring_data = k->k_rbuf[get];
               get = (get + 1) & KBD_RX_RING_MASK;

               /* low byte of ring_data is rr1 */
               c = (ring_data >> 8) & 0xff;

               if (ring_data & ZSRR1_DO)
                       intr_flags |= INTR_RX_OVERRUN;
               if (ring_data & (ZSRR1_FE | ZSRR1_PE)) {
                       /*
                        * After garbage, flush pending input, and
                        * send a reset to resync key translation.
                        */
                       log(LOG_ERR, "%s: input error (0x%x)\n",
                           device_xname(k->k_kbd.k_dev), ring_data);
                       get = k->k_rbput; /* flush */
                       goto send_reset;
               }

               /* Pass this up to the "middle" layer. */
               kbd_sun_input(k, c);
       }
       if (intr_flags & INTR_RX_OVERRUN) {
               log(LOG_ERR, "%s: input overrun\n",
                   device_xname(k->k_kbd.k_dev));
       send_reset:
               /* Send a reset to resync translation. */
               kbd_sun_output(k, KBD_CMD_RESET);
               kbd_sun_start_tx(k);
       }
       k->k_rbget = get;

       if (intr_flags & INTR_TX_EMPTY) {
               /*
                * Transmit done.  Try to send more, or
                * clear busy and wakeup drain waiters.
                */
               k->k_txflags &= ~K_TXBUSY;
               kbd_sun_start_tx(k);
       }

       if (intr_flags & INTR_ST_CHECK) {
               /*
                * Status line change.  (Not expected.)
                */
               log(LOG_ERR, "%s: status interrupt?\n",
                   device_xname(k->k_kbd.k_dev));
               cs->cs_rr0_delta = 0;
       }

       splx(s);
}