1 /*
2 * linux/arch/arm/plat-omap/debug-leds.c
3 *
4 * Copyright 2011 by Bryan Wu <bryan.wu@canonical.com>
5 * Copyright 2003 by Texas Instruments Incorporated
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/platform_device.h>
15 #include <linux/leds.h>
16 #include <linux/io.h>
17 #include <linux/platform_data/gpio-omap.h>
18 #include <linux/slab.h>
19
20 #include <asm/mach-types.h>
21
22 /* Many OMAP development platforms reuse the same "debug board"; these
23 * platforms include H2, H3, H4, and Perseus2. There are 16 LEDs on the
24 * debug board (all green), accessed through FPGA registers.
25 */
26
27 /* NOTE: most boards don't have a static mapping for the FPGA ... */
28 struct h2p2_dbg_fpga {
29 /* offset 0x00 */
30 u16 smc91x[8];
31 /* offset 0x10 */
32 u16 fpga_rev;
33 u16 board_rev;
34 u16 gpio_outputs;
35 u16 leds;
36 /* offset 0x18 */
37 u16 misc_inputs;
38 u16 lan_status;
39 u16 lan_reset;
40 u16 reserved0;
41 /* offset 0x20 */
42 u16 ps2_data;
43 u16 ps2_ctrl;
44 /* plus also 4 rs232 ports ... */
45 };
46
47 static struct h2p2_dbg_fpga __iomem *fpga;
48
49 static u16 fpga_led_state;
50
51 struct dbg_led {
52 struct led_classdev cdev;
53 u16 mask;
54 };
55
56 static const struct {
57 const char *name;
58 const char *trigger;
59 } dbg_leds[] = {
60 { "dbg:d4", "heartbeat", },
61 { "dbg:d5", "cpu0", },
62 { "dbg:d6", "default-on", },
63 { "dbg:d7", },
64 { "dbg:d8", },
65 { "dbg:d9", },
66 { "dbg:d10", },
67 { "dbg:d11", },
68 { "dbg:d12", },
69 { "dbg:d13", },
70 { "dbg:d14", },
71 { "dbg:d15", },
72 { "dbg:d16", },
73 { "dbg:d17", },
74 { "dbg:d18", },
75 { "dbg:d19", },
76 };
77
78 /*
79 * The triggers lines up below will only be used if the
80 * LED triggers are compiled in.
81 */
dbg_led_set(struct led_classdev * cdev,enum led_brightness b)82 static void dbg_led_set(struct led_classdev *cdev,
83 enum led_brightness b)
84 {
85 struct dbg_led *led = container_of(cdev, struct dbg_led, cdev);
86 u16 reg;
87
88 reg = readw_relaxed(&fpga->leds);
89 if (b != LED_OFF)
90 reg |= led->mask;
91 else
92 reg &= ~led->mask;
93 writew_relaxed(reg, &fpga->leds);
94 }
95
dbg_led_get(struct led_classdev * cdev)96 static enum led_brightness dbg_led_get(struct led_classdev *cdev)
97 {
98 struct dbg_led *led = container_of(cdev, struct dbg_led, cdev);
99 u16 reg;
100
101 reg = readw_relaxed(&fpga->leds);
102 return (reg & led->mask) ? LED_FULL : LED_OFF;
103 }
104
fpga_probe(struct platform_device * pdev)105 static int fpga_probe(struct platform_device *pdev)
106 {
107 struct resource *iomem;
108 int i;
109
110 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
111 if (!iomem)
112 return -ENODEV;
113
114 fpga = ioremap(iomem->start, resource_size(iomem));
115 writew_relaxed(0xff, &fpga->leds);
116
117 for (i = 0; i < ARRAY_SIZE(dbg_leds); i++) {
118 struct dbg_led *led;
119
120 led = kzalloc(sizeof(*led), GFP_KERNEL);
121 if (!led)
122 break;
123
124 led->cdev.name = dbg_leds[i].name;
125 led->cdev.brightness_set = dbg_led_set;
126 led->cdev.brightness_get = dbg_led_get;
127 led->cdev.default_trigger = dbg_leds[i].trigger;
128 led->mask = BIT(i);
129
130 if (led_classdev_register(NULL, &led->cdev) < 0) {
131 kfree(led);
132 break;
133 }
134 }
135
136 return 0;
137 }
138
fpga_suspend_noirq(struct device * dev)139 static int fpga_suspend_noirq(struct device *dev)
140 {
141 fpga_led_state = readw_relaxed(&fpga->leds);
142 writew_relaxed(0xff, &fpga->leds);
143
144 return 0;
145 }
146
fpga_resume_noirq(struct device * dev)147 static int fpga_resume_noirq(struct device *dev)
148 {
149 writew_relaxed(~fpga_led_state, &fpga->leds);
150 return 0;
151 }
152
153 static const struct dev_pm_ops fpga_dev_pm_ops = {
154 .suspend_noirq = fpga_suspend_noirq,
155 .resume_noirq = fpga_resume_noirq,
156 };
157
158 static struct platform_driver led_driver = {
159 .driver.name = "omap_dbg_led",
160 .driver.pm = &fpga_dev_pm_ops,
161 .probe = fpga_probe,
162 };
163
fpga_init(void)164 static int __init fpga_init(void)
165 {
166 if (machine_is_omap_h4()
167 || machine_is_omap_h3()
168 || machine_is_omap_h2()
169 || machine_is_omap_perseus2()
170 )
171 return platform_driver_register(&led_driver);
172 return 0;
173 }
174 fs_initcall(fpga_init);
175
