1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2024 Colin Percival
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include <sys/types.h>
29 #include <sys/bus.h>
30 #include <sys/gpio.h>
31 #include <sys/kernel.h>
32 #include <sys/module.h>
33
34 #include "gpiobus_if.h"
35
36 #include <contrib/dev/acpica/include/acpi.h>
37 #include <dev/acpica/acpivar.h>
38
39 #include <dev/gpio/gpiobusvar.h>
40 #include <dev/gpio/acpi_gpiobusvar.h>
41
42 enum gpio_aei_type {
43 ACPI_AEI_TYPE_UNKNOWN,
44 ACPI_AEI_TYPE_ELX,
45 ACPI_AEI_TYPE_EVT
46 };
47
48 struct gpio_aei_softc {
49 ACPI_HANDLE handle;
50 enum gpio_aei_type type;
51 int pin;
52 struct resource * intr_res;
53 int intr_rid;
54 void * intr_cookie;
55 };
56
57 static int
gpio_aei_probe(device_t dev)58 gpio_aei_probe(device_t dev)
59 {
60
61 /* We only match when gpiobus explicitly requested gpio_aei. */
62 return (BUS_PROBE_NOWILDCARD);
63 }
64
65 static void
gpio_aei_intr(void * arg)66 gpio_aei_intr(void * arg)
67 {
68 struct gpio_aei_softc * sc = arg;
69
70 /* Ask ACPI to run the appropriate _EVT, _Exx or _Lxx method. */
71 if (sc->type == ACPI_AEI_TYPE_EVT)
72 acpi_SetInteger(sc->handle, NULL, sc->pin);
73 else
74 AcpiEvaluateObject(sc->handle, NULL, NULL, NULL);
75 }
76
77 static int
gpio_aei_attach(device_t dev)78 gpio_aei_attach(device_t dev)
79 {
80 struct gpio_aei_softc * sc = device_get_softc(dev);
81 gpio_pin_t pin;
82 ACPI_HANDLE handle;
83 int err;
84
85 /* This is us. */
86 device_set_desc(dev, "ACPI Event Information Device");
87
88 /* Store parameters needed by gpio_aei_intr. */
89 handle = acpi_gpiobus_get_handle(dev);
90 if (gpio_pin_get_by_acpi_index(dev, 0, &pin) != 0) {
91 device_printf(dev, "Unable to get the input pin\n");
92 return (ENXIO);
93 }
94
95 sc->type = ACPI_AEI_TYPE_UNKNOWN;
96 sc->pin = pin->pin;
97 if (pin->pin <= 255) {
98 char objname[5]; /* "_EXX" or "_LXX" */
99 sprintf(objname, "_%c%02X",
100 (pin->flags & GPIO_INTR_EDGE_MASK) ? 'E' : 'L', pin->pin);
101 if (ACPI_SUCCESS(AcpiGetHandle(handle, objname, &sc->handle)))
102 sc->type = ACPI_AEI_TYPE_ELX;
103 }
104 if (sc->type == ACPI_AEI_TYPE_UNKNOWN) {
105 if (ACPI_SUCCESS(AcpiGetHandle(handle, "_EVT", &sc->handle)))
106 sc->type = ACPI_AEI_TYPE_EVT;
107 }
108
109 if (sc->type == ACPI_AEI_TYPE_UNKNOWN) {
110 device_printf(dev, "ACPI Event Information Device type is unknown");
111 return (ENOTSUP);
112 }
113
114 /* Set up the interrupt. */
115 if ((sc->intr_res = gpio_alloc_intr_resource(dev, &sc->intr_rid,
116 RF_ACTIVE, pin, pin->flags & GPIO_INTR_MASK)) == NULL) {
117 device_printf(dev, "Cannot allocate an IRQ\n");
118 return (ENOTSUP);
119 }
120 err = bus_setup_intr(dev, sc->intr_res, INTR_TYPE_MISC | INTR_MPSAFE,
121 NULL, gpio_aei_intr, sc, &sc->intr_cookie);
122 if (err != 0) {
123 device_printf(dev, "Cannot set up IRQ\n");
124 bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid,
125 sc->intr_res);
126 return (err);
127 }
128
129 return (0);
130 }
131
132 static int
gpio_aei_detach(device_t dev)133 gpio_aei_detach(device_t dev)
134 {
135 struct gpio_aei_softc * sc = device_get_softc(dev);
136
137 bus_teardown_intr(dev, sc->intr_res, sc->intr_cookie);
138 bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid, sc->intr_res);
139 return (0);
140 }
141
142 static device_method_t gpio_aei_methods[] = {
143 /* Device interface. */
144 DEVMETHOD(device_probe, gpio_aei_probe),
145 DEVMETHOD(device_attach, gpio_aei_attach),
146 DEVMETHOD(device_detach, gpio_aei_detach),
147
148 DEVMETHOD_END
149 };
150
151 DEFINE_CLASS_0(gpio_aei, gpio_aei_driver, gpio_aei_methods, sizeof(struct gpio_aei_softc));
152 DRIVER_MODULE(gpio_aei, gpiobus, gpio_aei_driver, NULL, NULL);
153 MODULE_DEPEND(gpio_aei, acpi_gpiobus, 1, 1, 1);
154