1 /* $NetBSD: acemidi.c,v 1.14 2008/03/14 15:09:11 cube 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 1.14 2008/03/14 15:09:11 cube Exp $"); 32 33 #include <sys/param.h> 34 35 #include <sys/device.h> 36 #include <sys/systm.h> 37 38 #include <sys/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 com_acemidi_softc { 49 struct com_softc sc_com; 50 struct evcnt sc_intrcnt; 51 }; 52 53 static int acemidi_match(device_t, cfdata_t , void *); 54 static void acemidi_attach(device_t, device_t, void *); 55 static int com_acemidi_match(device_t, cfdata_t, void *); 56 static void com_acemidi_attach(device_t, device_t, void *); 57 58 CFATTACH_DECL_NEW(acemidi, 0, 59 acemidi_match, acemidi_attach, NULL, NULL); 60 61 CFATTACH_DECL_NEW(com_acemidi, sizeof(struct com_acemidi_softc), 62 com_acemidi_match, com_acemidi_attach, NULL, NULL); 63 64 static int 65 acemidi_match(device_t parent, cfdata_t cf, void *aux) 66 { 67 struct podulebus_attach_args *pa = aux; 68 69 if (pa->pa_product == PODULE_MIDICONNECT) 70 return 1; 71 return 0; 72 } 73 74 static void 75 acemidi_attach(device_t parent, device_t self, void *aux) 76 { 77 /* struct acemidi_softc *sc = device_private(self); */ 78 /* struct podulebus_attach_args *pa = aux; */ 79 80 printf("\n"); 81 config_found_ia(self, "acemidi", aux, NULL); 82 } 83 84 static int 85 com_acemidi_match(device_t parent, cfdata_t cf, void *aux) 86 { 87 88 return 1; 89 } 90 91 static void 92 com_acemidi_attach(device_t parent, device_t self, void *aux) 93 { 94 struct com_acemidi_softc *sc = device_private(self); 95 struct com_softc *csc = &sc->sc_com; 96 struct podulebus_attach_args *pa = aux; 97 bus_space_handle_t ioh; 98 bus_space_tag_t iot; 99 bus_addr_t iobase; 100 101 iot = pa->pa_fast_t; 102 iobase = pa->pa_fast_base + ACEMIDI_16550_BASE; 103 104 bus_space_map(iot, iobase, COM_NPORTS, 0, &ioh); 105 COM_INIT_REGS(csc->sc_regs, iot, ioh, iobase); 106 107 csc->sc_frequency = ACEMIDI_16550_FREQ; 108 109 com_attach_subr(csc); 110 111 evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL, 112 device_xname(self), "intr"); 113 podulebus_irq_establish(pa->pa_ih, IPL_SERIAL, comintr, sc, 114 &sc->sc_intrcnt); 115 } 116 117 /* 118 * Stray IRQ bug: 119 * 120 * Occasionally, when receiving, we get a stray IRQ. Sometimes, the interrupt 121 * bit on the unixbp reads as clear. In any case, comintr() gets an IIR 122 * of 0xc1 (no interrupts pending). 123 * 124 * The behaviour can be observed with a logic probe: 125 * 126 * Channel 1 to PIRQ* (pin 19 on IC3 on A540 backplane) 127 * Channel 2 to INTR on 16550 128 * trigger on ch1 low, ch2 falling 129 * 2 us/div 130 * 131 * This catches cases where the 16550 de-asserts the interrupt before 132 * irq_handler is entered and disables the interrupt at unixbp (by calling 133 * splhigh()). 134 * 135 * This gets us 5us pulses on INTR and PIRQ*. Now to work out why. 136 * 137 * Connecting channel 3 to the CS2* pin on the 16550 shows it high throughout, 138 * so the interrupt isn't being cleared by the host. MR, similarly, is low 139 * throughout, so it's not being cleared by a reset. 140 */ 141