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 struct gpio_aei_softc {
43 ACPI_HANDLE handle;
44 char objname[5]; /* "_EXX" or "_LXX" */
45 struct resource * intr_res;
46 int intr_rid;
47 void * intr_cookie;
48 };
49
50 static int
gpio_aei_probe(device_t dev)51 gpio_aei_probe(device_t dev)
52 {
53
54 /* We only match when gpiobus explicitly requested gpio_aei. */
55 return (BUS_PROBE_NOWILDCARD);
56 }
57
58 static void
gpio_aei_intr(void * arg)59 gpio_aei_intr(void * arg)
60 {
61 struct gpio_aei_softc * sc = arg;
62
63 /* Ask ACPI to run the appropriate _Exx or _Lxx method. */
64 AcpiEvaluateObject(sc->handle, sc->objname, NULL, NULL);
65 }
66
67 static int
gpio_aei_attach(device_t dev)68 gpio_aei_attach(device_t dev)
69 {
70 struct gpio_aei_softc * sc = device_get_softc(dev);
71 gpio_pin_t pin;
72 int err;
73
74 /* This is us. */
75 device_set_desc(dev, "ACPI Event Information Device");
76
77 /* Store parameters needed by gpio_aei_intr. */
78 sc->handle = acpi_gpiobus_get_handle(dev);
79 if (gpio_pin_get_by_acpi_index(dev, 0, &pin) != 0) {
80 device_printf(dev, "Unable to get the input pin\n");
81 return (ENXIO);
82 }
83 sprintf(sc->objname, "_%c%02X",
84 (pin->flags & GPIO_INTR_EDGE_MASK) ? 'E' : 'L', pin->pin);
85
86 /* Support for GPIO pins > 255 is not implemented. */
87 if (pin->pin > 255) {
88 device_printf(dev, "ACPI Event Information Device does not support pins > 255");
89 return (ENOTSUP);
90 }
91
92 /* Set up the interrupt. */
93 if ((sc->intr_res = gpio_alloc_intr_resource(dev, &sc->intr_rid,
94 RF_ACTIVE, pin, pin->flags & GPIO_INTR_MASK)) == NULL) {
95 device_printf(dev, "Cannot allocate an IRQ\n");
96 return (ENOTSUP);
97 }
98 err = bus_setup_intr(dev, sc->intr_res, INTR_TYPE_MISC | INTR_MPSAFE,
99 NULL, gpio_aei_intr, sc, &sc->intr_cookie);
100 if (err != 0) {
101 device_printf(dev, "Cannot set up IRQ\n");
102 bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid,
103 sc->intr_res);
104 return (err);
105 }
106
107 return (0);
108 }
109
110 static int
gpio_aei_detach(device_t dev)111 gpio_aei_detach(device_t dev)
112 {
113 struct gpio_aei_softc * sc = device_get_softc(dev);
114
115 bus_teardown_intr(dev, sc->intr_res, sc->intr_cookie);
116 bus_release_resource(dev, SYS_RES_IRQ, sc->intr_rid, sc->intr_res);
117 return (0);
118 }
119
120 static device_method_t gpio_aei_methods[] = {
121 /* Device interface. */
122 DEVMETHOD(device_probe, gpio_aei_probe),
123 DEVMETHOD(device_attach, gpio_aei_attach),
124 DEVMETHOD(device_detach, gpio_aei_detach),
125
126 DEVMETHOD_END
127 };
128
129 DEFINE_CLASS_0(gpio_aei, gpio_aei_driver, gpio_aei_methods, sizeof(struct gpio_aei_softc));
130 DRIVER_MODULE(gpio_aei, gpiobus, gpio_aei_driver, NULL, NULL);
131 MODULE_DEPEND(gpio_aei, acpi_gpiobus, 1, 1, 1);
132