1/*
2 * System Specific setup for PCEngines ALIX.
3 * At the moment this means setup of GPIO control of LEDs
4 * on Alix.2/3/6 boards.
5 *
6 *
7 * Copyright (C) 2008 Constantin Baranov <const@mimas.ru>
8 * Copyright (C) 2011 Ed Wildgoose <kernel@wildgooses.com>
9 *                and Philip Prindeville <philipp@redfish-solutions.com>
10 *
11 * TODO: There are large similarities with leds-net5501.c
12 * by Alessandro Zummo <a.zummo@towertech.it>
13 * In the future leds-net5501.c should be migrated over to platform
14 *
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License version 2
17 * as published by the Free Software Foundation.
18 */
19
20#include <linux/kernel.h>
21#include <linux/init.h>
22#include <linux/io.h>
23#include <linux/string.h>
24#include <linux/module.h>
25#include <linux/leds.h>
26#include <linux/platform_device.h>
27#include <linux/gpio.h>
28#include <linux/input.h>
29#include <linux/gpio_keys.h>
30#include <linux/dmi.h>
31
32#include <asm/geode.h>
33
34#define BIOS_SIGNATURE_TINYBIOS		0xf0000
35#define BIOS_SIGNATURE_COREBOOT		0x500
36#define BIOS_REGION_SIZE		0x10000
37
38static bool force = 0;
39module_param(force, bool, 0444);
40/* FIXME: Award bios is not automatically detected as Alix platform */
41MODULE_PARM_DESC(force, "Force detection as ALIX.2/ALIX.3 platform");
42
43static struct gpio_keys_button alix_gpio_buttons[] = {
44	{
45		.code			= KEY_RESTART,
46		.gpio			= 24,
47		.active_low		= 1,
48		.desc			= "Reset button",
49		.type			= EV_KEY,
50		.wakeup			= 0,
51		.debounce_interval	= 100,
52		.can_disable		= 0,
53	}
54};
55static struct gpio_keys_platform_data alix_buttons_data = {
56	.buttons			= alix_gpio_buttons,
57	.nbuttons			= ARRAY_SIZE(alix_gpio_buttons),
58	.poll_interval			= 20,
59};
60
61static struct platform_device alix_buttons_dev = {
62	.name				= "gpio-keys-polled",
63	.id				= 1,
64	.dev = {
65		.platform_data		= &alix_buttons_data,
66	}
67};
68
69static struct gpio_led alix_leds[] = {
70	{
71		.name = "alix:1",
72		.gpio = 6,
73		.default_trigger = "default-on",
74		.active_low = 1,
75	},
76	{
77		.name = "alix:2",
78		.gpio = 25,
79		.default_trigger = "default-off",
80		.active_low = 1,
81	},
82	{
83		.name = "alix:3",
84		.gpio = 27,
85		.default_trigger = "default-off",
86		.active_low = 1,
87	},
88};
89
90static struct gpio_led_platform_data alix_leds_data = {
91	.num_leds = ARRAY_SIZE(alix_leds),
92	.leds = alix_leds,
93};
94
95static struct platform_device alix_leds_dev = {
96	.name = "leds-gpio",
97	.id = -1,
98	.dev.platform_data = &alix_leds_data,
99};
100
101static struct platform_device *alix_devs[] __initdata = {
102	&alix_buttons_dev,
103	&alix_leds_dev,
104};
105
106static void __init register_alix(void)
107{
108	/* Setup LED control through leds-gpio driver */
109	platform_add_devices(alix_devs, ARRAY_SIZE(alix_devs));
110}
111
112static bool __init alix_present(unsigned long bios_phys,
113				const char *alix_sig,
114				size_t alix_sig_len)
115{
116	const size_t bios_len = BIOS_REGION_SIZE;
117	const char *bios_virt;
118	const char *scan_end;
119	const char *p;
120	char name[64];
121
122	if (force) {
123		printk(KERN_NOTICE "%s: forced to skip BIOS test, "
124		       "assume system is ALIX.2/ALIX.3\n",
125		       KBUILD_MODNAME);
126		return true;
127	}
128
129	bios_virt = phys_to_virt(bios_phys);
130	scan_end = bios_virt + bios_len - (alix_sig_len + 2);
131	for (p = bios_virt; p < scan_end; p++) {
132		const char *tail;
133		char *a;
134
135		if (memcmp(p, alix_sig, alix_sig_len) != 0)
136			continue;
137
138		memcpy(name, p, sizeof(name));
139
140		/* remove the first \0 character from string */
141		a = strchr(name, '\0');
142		if (a)
143			*a = ' ';
144
145		/* cut the string at a newline */
146		a = strchr(name, '\r');
147		if (a)
148			*a = '\0';
149
150		tail = p + alix_sig_len;
151		if ((tail[0] == '2' || tail[0] == '3' || tail[0] == '6')) {
152			printk(KERN_INFO
153			       "%s: system is recognized as \"%s\"\n",
154			       KBUILD_MODNAME, name);
155			return true;
156		}
157	}
158
159	return false;
160}
161
162static bool __init alix_present_dmi(void)
163{
164	const char *vendor, *product;
165
166	vendor = dmi_get_system_info(DMI_SYS_VENDOR);
167	if (!vendor || strcmp(vendor, "PC Engines"))
168		return false;
169
170	product = dmi_get_system_info(DMI_PRODUCT_NAME);
171	if (!product || (strcmp(product, "ALIX.2D") && strcmp(product, "ALIX.6")))
172		return false;
173
174	printk(KERN_INFO "%s: system is recognized as \"%s %s\"\n",
175	       KBUILD_MODNAME, vendor, product);
176
177	return true;
178}
179
180static int __init alix_init(void)
181{
182	const char tinybios_sig[] = "PC Engines ALIX.";
183	const char coreboot_sig[] = "PC Engines\0ALIX.";
184
185	if (!is_geode())
186		return 0;
187
188	if (alix_present(BIOS_SIGNATURE_TINYBIOS, tinybios_sig, sizeof(tinybios_sig) - 1) ||
189	    alix_present(BIOS_SIGNATURE_COREBOOT, coreboot_sig, sizeof(coreboot_sig) - 1) ||
190	    alix_present_dmi())
191		register_alix();
192
193	return 0;
194}
195
196module_init(alix_init);
197
198MODULE_AUTHOR("Ed Wildgoose <kernel@wildgooses.com>");
199MODULE_DESCRIPTION("PCEngines ALIX System Setup");
200MODULE_LICENSE("GPL");
201