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 ... */
 28struct 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
 47static struct h2p2_dbg_fpga __iomem *fpga;
 48
 49static u16 fpga_led_state;
 50
 51struct dbg_led {
 52	struct led_classdev	cdev;
 53	u16			mask;
 54};
 55
 56static 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 */
 82static 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
 96static 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
105static 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
139static 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
147static int fpga_resume_noirq(struct device *dev)
148{
149	writew_relaxed(~fpga_led_state, &fpga->leds);
150	return 0;
151}
152
153static const struct dev_pm_ops fpga_dev_pm_ops = {
154	.suspend_noirq = fpga_suspend_noirq,
155	.resume_noirq = fpga_resume_noirq,
156};
157
158static struct platform_driver led_driver = {
159	.driver.name	= "omap_dbg_led",
160	.driver.pm	= &fpga_dev_pm_ops,
161	.probe		= fpga_probe,
162};
163
164static 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}
174fs_initcall(fpga_init);