/arch/arm/plat-omap/debug-leds.c

  1/*
  2 * linux/arch/arm/plat-omap/debug-leds.c
  3 *
  4 * Copyright 2003 by Texas Instruments Incorporated
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 as
  8 * published by the Free Software Foundation.
  9 */
 10
 11#include <linux/init.h>
 12#include <linux/platform_device.h>
 13#include <linux/leds.h>
 14#include <linux/io.h>
 15
 16#include <mach/hardware.h>
 17#include <asm/leds.h>
 18#include <asm/system.h>
 19#include <asm/mach-types.h>
 20
 21#include <plat/fpga.h>
 22#include <mach/gpio.h>
 23
 24
 25/* Many OMAP development platforms reuse the same "debug board"; these
 26 * platforms include H2, H3, H4, and Perseus2.  There are 16 LEDs on the
 27 * debug board (all green), accessed through FPGA registers.
 28 *
 29 * The "surfer" expansion board and H2 sample board also have two-color
 30 * green+red LEDs (in parallel), used here for timer and idle indicators
 31 * in preference to the ones on the debug board, for a "Disco LED" effect.
 32 *
 33 * This driver exports either the original ARM LED API, the new generic
 34 * one, or both.
 35 */
 36
 37static spinlock_t			lock;
 38static struct h2p2_dbg_fpga __iomem	*fpga;
 39static u16				led_state, hw_led_state;
 40
 41
 42#ifdef	CONFIG_LEDS_OMAP_DEBUG
 43#define new_led_api()	1
 44#else
 45#define new_led_api()	0
 46#endif
 47
 48
 49/*-------------------------------------------------------------------------*/
 50
 51/* original ARM debug LED API:
 52 *  - timer and idle leds (some boards use non-FPGA leds here);
 53 *  - up to 4 generic leds, easily accessed in-kernel (any context)
 54 */
 55
 56#define GPIO_LED_RED		3
 57#define GPIO_LED_GREEN		OMAP_MPUIO(4)
 58
 59#define LED_STATE_ENABLED	0x01
 60#define LED_STATE_CLAIMED	0x02
 61#define LED_TIMER_ON		0x04
 62
 63#define GPIO_IDLE		GPIO_LED_GREEN
 64#define GPIO_TIMER		GPIO_LED_RED
 65
 66static void h2p2_dbg_leds_event(led_event_t evt)
 67{
 68	unsigned long flags;
 69
 70	spin_lock_irqsave(&lock, flags);
 71
 72	if (!(led_state & LED_STATE_ENABLED) && evt != led_start)
 73		goto done;
 74
 75	switch (evt) {
 76	case led_start:
 77		if (fpga)
 78			led_state |= LED_STATE_ENABLED;
 79		break;
 80
 81	case led_stop:
 82	case led_halted:
 83		/* all leds off during suspend or shutdown */
 84
 85		if (!(machine_is_omap_perseus2() || machine_is_omap_h4())) {
 86			gpio_set_value(GPIO_TIMER, 0);
 87			gpio_set_value(GPIO_IDLE, 0);
 88		}
 89
 90		__raw_writew(~0, &fpga->leds);
 91		led_state &= ~LED_STATE_ENABLED;
 92		goto done;
 93
 94	case led_claim:
 95		led_state |= LED_STATE_CLAIMED;
 96		hw_led_state = 0;
 97		break;
 98
 99	case led_release:
100		led_state &= ~LED_STATE_CLAIMED;
101		break;
102
103#ifdef CONFIG_LEDS_TIMER
104	case led_timer:
105		led_state ^= LED_TIMER_ON;
106
107		if (machine_is_omap_perseus2() || machine_is_omap_h4())
108			hw_led_state ^= H2P2_DBG_FPGA_P2_LED_TIMER;
109		else {
110			gpio_set_value(GPIO_TIMER,
111					led_state & LED_TIMER_ON);
112			goto done;
113		}
114
115		break;
116#endif
117
118#ifdef CONFIG_LEDS_CPU
119	/* LED lit iff busy */
120	case led_idle_start:
121		if (machine_is_omap_perseus2() || machine_is_omap_h4())
122			hw_led_state &= ~H2P2_DBG_FPGA_P2_LED_IDLE;
123		else {
124			gpio_set_value(GPIO_IDLE, 1);
125			goto done;
126		}
127
128		break;
129
130	case led_idle_end:
131		if (machine_is_omap_perseus2() || machine_is_omap_h4())
132			hw_led_state |= H2P2_DBG_FPGA_P2_LED_IDLE;
133		else {
134			gpio_set_value(GPIO_IDLE, 0);
135			goto done;
136		}
137
138		break;
139#endif
140
141	case led_green_on:
142		hw_led_state |= H2P2_DBG_FPGA_LED_GREEN;
143		break;
144	case led_green_off:
145		hw_led_state &= ~H2P2_DBG_FPGA_LED_GREEN;
146		break;
147
148	case led_amber_on:
149		hw_led_state |= H2P2_DBG_FPGA_LED_AMBER;
150		break;
151	case led_amber_off:
152		hw_led_state &= ~H2P2_DBG_FPGA_LED_AMBER;
153		break;
154
155	case led_red_on:
156		hw_led_state |= H2P2_DBG_FPGA_LED_RED;
157		break;
158	case led_red_off:
159		hw_led_state &= ~H2P2_DBG_FPGA_LED_RED;
160		break;
161
162	case led_blue_on:
163		hw_led_state |= H2P2_DBG_FPGA_LED_BLUE;
164		break;
165	case led_blue_off:
166		hw_led_state &= ~H2P2_DBG_FPGA_LED_BLUE;
167		break;
168
169	default:
170		break;
171	}
172
173
174	/*
175	 *  Actually burn the LEDs
176	 */
177	if (led_state & LED_STATE_ENABLED)
178		__raw_writew(~hw_led_state, &fpga->leds);
179
180done:
181	spin_unlock_irqrestore(&lock, flags);
182}
183
184/*-------------------------------------------------------------------------*/
185
186/* "new" LED API
187 *  - with syfs access and generic triggering
188 *  - not readily accessible to in-kernel drivers
189 */
190
191struct dbg_led {
192	struct led_classdev	cdev;
193	u16			mask;
194};
195
196static struct dbg_led dbg_leds[] = {
197	/* REVISIT at least H2 uses different timer & cpu leds... */
198#ifndef CONFIG_LEDS_TIMER
199	{ .mask = 1 << 0,  .cdev.name =  "d4:green",
200		.cdev.default_trigger = "heartbeat", },
201#endif
202#ifndef CONFIG_LEDS_CPU
203	{ .mask = 1 << 1,  .cdev.name =  "d5:green", },		/* !idle */
204#endif
205	{ .mask = 1 << 2,  .cdev.name =  "d6:green", },
206	{ .mask = 1 << 3,  .cdev.name =  "d7:green", },
207
208	{ .mask = 1 << 4,  .cdev.name =  "d8:green", },
209	{ .mask = 1 << 5,  .cdev.name =  "d9:green", },
210	{ .mask = 1 << 6,  .cdev.name = "d10:green", },
211	{ .mask = 1 << 7,  .cdev.name = "d11:green", },
212
213	{ .mask = 1 << 8,  .cdev.name = "d12:green", },
214	{ .mask = 1 << 9,  .cdev.name = "d13:green", },
215	{ .mask = 1 << 10, .cdev.name = "d14:green", },
216	{ .mask = 1 << 11, .cdev.name = "d15:green", },
217
218#ifndef	CONFIG_LEDS
219	{ .mask = 1 << 12, .cdev.name = "d16:green", },
220	{ .mask = 1 << 13, .cdev.name = "d17:green", },
221	{ .mask = 1 << 14, .cdev.name = "d18:green", },
222	{ .mask = 1 << 15, .cdev.name = "d19:green", },
223#endif
224};
225
226static void
227fpga_led_set(struct led_classdev *cdev, enum led_brightness value)
228{
229	struct dbg_led	*led = container_of(cdev, struct dbg_led, cdev);
230	unsigned long	flags;
231
232	spin_lock_irqsave(&lock, flags);
233	if (value == LED_OFF)
234		hw_led_state &= ~led->mask;
235	else
236		hw_led_state |= led->mask;
237	__raw_writew(~hw_led_state, &fpga->leds);
238	spin_unlock_irqrestore(&lock, flags);
239}
240
241static void __init newled_init(struct device *dev)
242{
243	unsigned	i;
244	struct dbg_led	*led;
245	int		status;
246
247	for (i = 0, led = dbg_leds; i < ARRAY_SIZE(dbg_leds); i++, led++) {
248		led->cdev.brightness_set = fpga_led_set;
249		status = led_classdev_register(dev, &led->cdev);
250		if (status < 0)
251			break;
252	}
253	return;
254}
255
256
257/*-------------------------------------------------------------------------*/
258
259static int /* __init */ fpga_probe(struct platform_device *pdev)
260{
261	struct resource	*iomem;
262
263	spin_lock_init(&lock);
264
265	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
266	if (!iomem)
267		return -ENODEV;
268
269	fpga = ioremap(iomem->start, H2P2_DBG_FPGA_SIZE);
270	__raw_writew(~0, &fpga->leds);
271
272#ifdef	CONFIG_LEDS
273	leds_event = h2p2_dbg_leds_event;
274	leds_event(led_start);
275#endif
276
277	if (new_led_api()) {
278		newled_init(&pdev->dev);
279	}
280
281	return 0;
282}
283
284static int fpga_suspend_noirq(struct device *dev)
285{
286	__raw_writew(~0, &fpga->leds);
287	return 0;
288}
289
290static int fpga_resume_noirq(struct device *dev)
291{
292	__raw_writew(~hw_led_state, &fpga->leds);
293	return 0;
294}
295
296static const struct dev_pm_ops fpga_dev_pm_ops = {
297	.suspend_noirq = fpga_suspend_noirq,
298	.resume_noirq = fpga_resume_noirq,
299};
300
301static struct platform_driver led_driver = {
302	.driver.name	= "omap_dbg_led",
303	.driver.pm	= &fpga_dev_pm_ops,
304	.probe		= fpga_probe,
305};
306
307static int __init fpga_init(void)
308{
309	if (machine_is_omap_h4()
310			|| machine_is_omap_h3()
311			|| machine_is_omap_h2()
312			|| machine_is_omap_perseus2()
313			)
314		return platform_driver_register(&led_driver);
315	return 0;
316}
317fs_initcall(fpga_init);