1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/arch/arm/mach-footbridge/ebsa285.c
4  *
5  * EBSA285 machine fixup
6  */
7 #include <linux/init.h>
8 #include <linux/io.h>
9 #include <linux/spinlock.h>
10 #include <linux/slab.h>
11 #include <linux/leds.h>
12 
13 #include <asm/hardware/dec21285.h>
14 #include <asm/mach-types.h>
15 
16 #include <asm/mach/arch.h>
17 
18 #include "common.h"
19 
20 /* LEDs */
21 #if defined(CONFIG_NEW_LEDS) && defined(CONFIG_LEDS_CLASS)
22 #define XBUS_AMBER_L	BIT(0)
23 #define XBUS_GREEN_L	BIT(1)
24 #define XBUS_RED_L	BIT(2)
25 #define XBUS_TOGGLE	BIT(7)
26 
27 struct ebsa285_led {
28 	struct led_classdev     cdev;
29 	u8                      mask;
30 };
31 
32 /*
33  * The triggers lines up below will only be used if the
34  * LED triggers are compiled in.
35  */
36 static const struct {
37 	const char *name;
38 	const char *trigger;
39 } ebsa285_leds[] = {
40 	{ "ebsa285:amber", "cpu0", },
41 	{ "ebsa285:green", "heartbeat", },
42 	{ "ebsa285:red",},
43 };
44 
45 static unsigned char hw_led_state;
46 static void __iomem *xbus;
47 
ebsa285_led_set(struct led_classdev * cdev,enum led_brightness b)48 static void ebsa285_led_set(struct led_classdev *cdev,
49 		enum led_brightness b)
50 {
51 	struct ebsa285_led *led = container_of(cdev,
52 			struct ebsa285_led, cdev);
53 
54 	if (b == LED_OFF)
55 		hw_led_state |= led->mask;
56 	else
57 		hw_led_state &= ~led->mask;
58 	writeb(hw_led_state, xbus);
59 }
60 
ebsa285_led_get(struct led_classdev * cdev)61 static enum led_brightness ebsa285_led_get(struct led_classdev *cdev)
62 {
63 	struct ebsa285_led *led = container_of(cdev,
64 			struct ebsa285_led, cdev);
65 
66 	return hw_led_state & led->mask ? LED_OFF : LED_FULL;
67 }
68 
ebsa285_leds_init(void)69 static int __init ebsa285_leds_init(void)
70 {
71 	int i;
72 
73 	if (!machine_is_ebsa285())
74 		return -ENODEV;
75 
76 	xbus = ioremap(XBUS_CS2, SZ_4K);
77 	if (!xbus)
78 		return -ENOMEM;
79 
80 	/* 3 LEDS all off */
81 	hw_led_state = XBUS_AMBER_L | XBUS_GREEN_L | XBUS_RED_L;
82 	writeb(hw_led_state, xbus);
83 
84 	for (i = 0; i < ARRAY_SIZE(ebsa285_leds); i++) {
85 		struct ebsa285_led *led;
86 
87 		led = kzalloc(sizeof(*led), GFP_KERNEL);
88 		if (!led)
89 			break;
90 
91 		led->cdev.name = ebsa285_leds[i].name;
92 		led->cdev.brightness_set = ebsa285_led_set;
93 		led->cdev.brightness_get = ebsa285_led_get;
94 		led->cdev.default_trigger = ebsa285_leds[i].trigger;
95 		led->mask = BIT(i);
96 
97 		if (led_classdev_register(NULL, &led->cdev) < 0) {
98 			kfree(led);
99 			break;
100 		}
101 	}
102 
103 	return 0;
104 }
105 
106 /*
107  * Since we may have triggers on any subsystem, defer registration
108  * until after subsystem_init.
109  */
110 fs_initcall(ebsa285_leds_init);
111 #endif
112 
113 MACHINE_START(EBSA285, "EBSA285")
114 	/* Maintainer: Russell King */
115 	.atag_offset	= 0x100,
116 	.video_start	= 0x000a0000,
117 	.video_end	= 0x000bffff,
118 	.map_io		= footbridge_map_io,
119 	.init_early	= footbridge_sched_clock,
120 	.init_irq	= footbridge_init_irq,
121 	.init_time	= footbridge_timer_init,
122 	.restart	= footbridge_restart,
123 MACHINE_END
124 
125