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 uint32_t flags;
83 ACPI_HANDLE handle;
84 int err;
85
86 /* This is us. */
87 device_set_desc(dev, "ACPI Event Information Device");
88
89 /* Store parameters needed by gpio_aei_intr. */
90 handle = acpi_gpiobus_get_handle(dev);
91 if (gpio_pin_get_by_child_index(dev, 0, &pin) != 0) {
92 device_printf(dev, "Unable to get the input pin\n");
93 return (ENXIO);
94 }
95
96 sc->type = ACPI_AEI_TYPE_UNKNOWN;
97 sc->pin = pin->pin;
98
99 flags = acpi_gpiobus_get_flags(dev);
100 if (pin->pin <= 255) {
101 char objname[5]; /* "_EXX" or "_LXX" */
102 sprintf(objname, "_%c%02X",
103 (flags & GPIO_INTR_EDGE_MASK) ? 'E' : 'L', pin->pin);
104 if (ACPI_SUCCESS(AcpiGetHandle(handle, objname, &sc->handle)))
105 sc->type = ACPI_AEI_TYPE_ELX;
106 }
107 if (sc->type == ACPI_AEI_TYPE_UNKNOWN) {
108 if (ACPI_SUCCESS(AcpiGetHandle(handle, "_EVT", &sc->handle)))
109 sc->type = ACPI_AEI_TYPE_EVT;
110 }
111
112 if (sc->type == ACPI_AEI_TYPE_UNKNOWN) {
113 device_printf(dev, "ACPI Event Information Device type is unknown");
114 return (ENOTSUP);
115 }
116
117 /* Set up the interrupt. */
118 if ((sc->intr_res = gpio_alloc_intr_resource(dev, &sc->intr_rid,
119 RF_ACTIVE, pin, flags & GPIO_INTR_MASK)) == NULL) {
120 device_printf(dev, "Cannot allocate an IRQ\n");
121 return (ENOTSUP);
122 }
123 err = bus_setup_intr(dev, sc->intr_res, INTR_TYPE_MISC | INTR_MPSAFE |
124 INTR_EXCL | INTR_SLEEPABLE, NULL, gpio_aei_intr, sc,
125 &sc->intr_cookie);
126 if (err != 0) {
127 device_printf(dev, "Cannot set up IRQ\n");
128 bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid,
129 sc->intr_res);
130 return (err);
131 }
132
133 return (0);
134 }
135
136 static int
gpio_aei_detach(device_t dev)137 gpio_aei_detach(device_t dev)
138 {
139 struct gpio_aei_softc * sc = device_get_softc(dev);
140
141 bus_teardown_intr(dev, sc->intr_res, sc->intr_cookie);
142 bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid, sc->intr_res);
143 return (0);
144 }
145
146 static device_method_t gpio_aei_methods[] = {
147 /* Device interface. */
148 DEVMETHOD(device_probe, gpio_aei_probe),
149 DEVMETHOD(device_attach, gpio_aei_attach),
150 DEVMETHOD(device_detach, gpio_aei_detach),
151
152 DEVMETHOD_END
153 };
154
155 DEFINE_CLASS_0(gpio_aei, gpio_aei_driver, gpio_aei_methods, sizeof(struct gpio_aei_softc));
156 DRIVER_MODULE(gpio_aei, gpiobus, gpio_aei_driver, NULL, NULL);
157 MODULE_DEPEND(gpio_aei, acpi_gpiobus, 1, 1, 1);
158