omap4_gpio.c revision 273262 
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: head/sys/arm/ti/omap4/omap4_gpio.c 273262 2014-10-18 17:51:34Z andrew $");
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
53static struct ofw_compat_data compat_data[] = {
54	{"ti,omap4-gpio",	1},
55	{"ti,gpio",		1},
56	{NULL,			0},
57};
58
59static int
60omap4_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
76static int
77omap4_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
94static int
95omap4_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
126static 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
137extern driver_t ti_gpio_driver;
138static devclass_t omap4_gpio_devclass;
139
140DEFINE_CLASS_1(gpio, omap4_gpio_driver, omap4_gpio_methods,
141    sizeof(struct ti_gpio_softc), ti_gpio_driver);
142DRIVER_MODULE(omap4_gpio, simplebus, omap4_gpio_driver, omap4_gpio_devclass,
143    0, 0);
144