xref: /freebsd/sys/arm/ti/omap4/omap4_gpio.c (revision ff0ba87247820afbdfdc1b307c803f7923d0e4d3)
1 /*-
2  * Copyright (c) 2011 Ben Gray <ben.r.gray@gmail.com>.
3  * Copyright (c) 2014 Andrew Turner <andrew@FreeBSD.org>
4  * All rights reserved.
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  * 3. The name of the company nor the name of the author may be used to
15  *    endorse or promote products derived from this software without specific
16  *    prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY BEN GRAY ``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 BEN GRAY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
24  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
27  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/bus.h>
37 #include <sys/gpio.h>
38 
39 #include <machine/bus.h>
40 
41 #include <dev/fdt/fdt_common.h>
42 #include <dev/ofw/ofw_bus.h>
43 #include <dev/ofw/ofw_bus_subr.h>
44 
45 #include <arm/ti/ti_cpuid.h>
46 #include <arm/ti/ti_gpio.h>
47 #include <arm/ti/ti_scm.h>
48 
49 #include <arm/ti/omap4/omap4_scm_padconf.h>
50 
51 #include "ti_gpio_if.h"
52 
53 static struct ofw_compat_data compat_data[] = {
54 	{"ti,omap4-gpio",	1},
55 	{"ti,gpio",		1},
56 	{NULL,			0},
57 };
58 
59 static int
60 omap4_gpio_probe(device_t dev)
61 {
62 	if (ti_chip() != CHIP_OMAP_4)
63 		return (ENXIO);
64 
65 	if (!ofw_bus_status_okay(dev))
66 		return (ENXIO);
67 
68 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
69 		return (ENXIO);
70 
71 	device_set_desc(dev, "Ti OMAP4 General Purpose I/O (GPIO)");
72 
73 	return (0);
74 }
75 
76 static int
77 omap4_gpio_set_flags(device_t dev, uint32_t gpio, uint32_t flags)
78 {
79 	unsigned int state = 0;
80 	/* First the SCM driver needs to be told to put the pad into GPIO mode */
81 	if (flags & GPIO_PIN_OUTPUT)
82 		state = PADCONF_PIN_OUTPUT;
83 	else if (flags & GPIO_PIN_INPUT) {
84 		if (flags & GPIO_PIN_PULLUP)
85 			state = PADCONF_PIN_INPUT_PULLUP;
86 		else if (flags & GPIO_PIN_PULLDOWN)
87 			state = PADCONF_PIN_INPUT_PULLDOWN;
88 		else
89 			state = PADCONF_PIN_INPUT;
90 	}
91 	return ti_scm_padconf_set_gpiomode(gpio, state);
92 }
93 
94 static int
95 omap4_gpio_get_flags(device_t dev, uint32_t gpio, uint32_t *flags)
96 {
97 	unsigned int state;
98 
99 	/* Get the current pin state */
100 	if (ti_scm_padconf_get_gpiomode(gpio, &state) != 0) {
101 		*flags = 0;
102 		return (EINVAL);
103 	} else {
104 		switch (state) {
105 			case PADCONF_PIN_OUTPUT:
106 				*flags = GPIO_PIN_OUTPUT;
107 				break;
108 			case PADCONF_PIN_INPUT:
109 				*flags = GPIO_PIN_INPUT;
110 				break;
111 			case PADCONF_PIN_INPUT_PULLUP:
112 				*flags = GPIO_PIN_INPUT | GPIO_PIN_PULLUP;
113 				break;
114 			case PADCONF_PIN_INPUT_PULLDOWN:
115 				*flags = GPIO_PIN_INPUT | GPIO_PIN_PULLDOWN;
116 				break;
117 			default:
118 				*flags = 0;
119 				break;
120 		}
121 	}
122 
123 	return (0);
124 }
125 
126 static device_method_t omap4_gpio_methods[] = {
127 	/* bus interface */
128 	DEVMETHOD(device_probe, omap4_gpio_probe),
129 
130 	/* ti_gpio interface */
131 	DEVMETHOD(ti_gpio_set_flags, omap4_gpio_set_flags),
132 	DEVMETHOD(ti_gpio_get_flags, omap4_gpio_get_flags),
133 
134 	DEVMETHOD_END
135 };
136 
137 extern driver_t ti_gpio_driver;
138 static devclass_t omap4_gpio_devclass;
139 
140 DEFINE_CLASS_1(gpio, omap4_gpio_driver, omap4_gpio_methods,
141     sizeof(struct ti_gpio_softc), ti_gpio_driver);
142 DRIVER_MODULE(omap4_gpio, simplebus, omap4_gpio_driver, omap4_gpio_devclass,
143     0, 0);
144