1 /* $NetBSD: acemidi.c,v 1.4 2002/05/22 22:43:13 bjh21 Exp $ */ 2 3 /*- 4 * Copyright (c) 2001 Ben Harris 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __KERNEL_RCSID(0, "$NetBSD: acemidi.c,v 1.4 2002/05/22 22:43:13 bjh21 Exp $"); 32 33 #include <sys/param.h> 34 35 #include <sys/device.h> 36 #include <sys/systm.h> 37 38 #include <machine/bus.h> 39 40 #include <dev/podulebus/podulebus.h> 41 #include <dev/podulebus/podules.h> 42 #include <dev/podulebus/acemidireg.h> 43 44 #include <sys/termios.h> 45 #include <dev/ic/comvar.h> 46 #include <dev/ic/comreg.h> 47 48 struct acemidi_softc { 49 struct device sc_dev; 50 }; 51 52 struct com_acemidi_softc { 53 struct com_softc sc_com; 54 struct evcnt sc_intrcnt; 55 }; 56 57 static int acemidi_match(struct device *, struct cfdata *, void *); 58 static void acemidi_attach(struct device *, struct device *, void *); 59 static int com_acemidi_match(struct device *, struct cfdata *, void *); 60 static void com_acemidi_attach(struct device *, struct device *, void *); 61 62 struct cfattach acemidi_ca = { 63 sizeof(struct acemidi_softc), acemidi_match, acemidi_attach 64 }; 65 66 struct cfattach com_acemidi_ca = { 67 sizeof(struct com_acemidi_softc), com_acemidi_match, com_acemidi_attach 68 }; 69 70 static int 71 acemidi_match(struct device *parent, struct cfdata *cf, void *aux) 72 { 73 struct podulebus_attach_args *pa = aux; 74 75 if (pa->pa_product == PODULE_MIDICONNECT) 76 return 1; 77 return 0; 78 } 79 80 static void 81 acemidi_attach(struct device *parent, struct device *self, void *aux) 82 { 83 /* struct acemidi_softc *sc = (void *)self; */ 84 /* struct podulebus_attach_args *pa = aux; */ 85 86 printf("\n"); 87 config_found_sm(self, aux, NULL, NULL); 88 } 89 90 static int 91 com_acemidi_match(struct device *parent, struct cfdata *cf, void *aux) 92 { 93 94 return 1; 95 } 96 97 static void 98 com_acemidi_attach(struct device *parent, struct device *self, void *aux) 99 { 100 struct com_acemidi_softc *sc = (void *)self; 101 struct com_softc *csc = &sc->sc_com; 102 struct podulebus_attach_args *pa = aux; 103 104 csc->sc_iobase = pa->pa_fast_base + ACEMIDI_16550_BASE; 105 csc->sc_iot = pa->pa_fast_t; 106 bus_space_map(csc->sc_iot, csc->sc_iobase, COM_NPORTS, 0, 107 &csc->sc_ioh); 108 csc->sc_frequency = ACEMIDI_16550_FREQ; 109 110 com_attach_subr(csc); 111 112 evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL, 113 self->dv_xname, "intr"); 114 podulebus_irq_establish(pa->pa_ih, IPL_SERIAL, comintr, sc, 115 &sc->sc_intrcnt); 116 } 117 118 /* 119 * Stray IRQ bug: 120 * 121 * Occasionally, when receiving, we get a stray IRQ. Sometimes, the interrupt 122 * bit on the unixbp reads as clear. In any case, comintr() gets an IIR 123 * of 0xc1 (no interrupts pending). 124 * 125 * The behaviour can be observed with a logic probe: 126 * 127 * Channel 1 to PIRQ* (pin 19 on IC3 on A540 backplane) 128 * Channel 2 to INTR on 16550 129 * trigger on ch1 low, ch2 falling 130 * 2 us/div 131 * 132 * This catches cases where the 16550 de-asserts the interrupt before 133 * irq_handler is entered and disables the interrupt at unixbp (by calling 134 * splhigh()). 135 * 136 * This gets us 5us pulses on INTR and PIRQ*. Now to work out why. 137 * 138 * Connecting channel 3 to the CS2* pin on the 16550 shows it high throughout, 139 * so the interrupt isn't being cleared by the host. MR, similarly, is low 140 * throughout, so it's not being cleared by a reset. 141 */ 142