diff options
Diffstat (limited to 'arch/arm/plat-omap/debug-leds.c')
| -rw-r--r-- | arch/arm/plat-omap/debug-leds.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/arm/plat-omap/debug-leds.c b/arch/arm/plat-omap/debug-leds.c new file mode 100644 index 000000000..48b69de89 --- /dev/null +++ b/arch/arm/plat-omap/debug-leds.c @@ -0,0 +1,174 @@ +/* + * linux/arch/arm/plat-omap/debug-leds.c + * + * Copyright 2011 by Bryan Wu <bryan.wu@canonical.com> + * Copyright 2003 by Texas Instruments Incorporated + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/leds.h> +#include <linux/io.h> +#include <linux/platform_data/gpio-omap.h> +#include <linux/slab.h> + +#include <asm/mach-types.h> + +/* Many OMAP development platforms reuse the same "debug board"; these + * platforms include H2, H3, H4, and Perseus2. There are 16 LEDs on the + * debug board (all green), accessed through FPGA registers. + */ + +/* NOTE: most boards don't have a static mapping for the FPGA ... */ +struct h2p2_dbg_fpga { + /* offset 0x00 */ + u16 smc91x[8]; + /* offset 0x10 */ + u16 fpga_rev; + u16 board_rev; + u16 gpio_outputs; + u16 leds; + /* offset 0x18 */ + u16 misc_inputs; + u16 lan_status; + u16 lan_reset; + u16 reserved0; + /* offset 0x20 */ + u16 ps2_data; + u16 ps2_ctrl; + /* plus also 4 rs232 ports ... */ +}; + +static struct h2p2_dbg_fpga __iomem *fpga; + +static u16 fpga_led_state; + +struct dbg_led { + struct led_classdev cdev; + u16 mask; +}; + +static const struct { + const char *name; + const char *trigger; +} dbg_leds[] = { + { "dbg:d4", "heartbeat", }, + { "dbg:d5", "cpu0", }, + { "dbg:d6", "default-on", }, + { "dbg:d7", }, + { "dbg:d8", }, + { "dbg:d9", }, + { "dbg:d10", }, + { "dbg:d11", }, + { "dbg:d12", }, + { "dbg:d13", }, + { "dbg:d14", }, + { "dbg:d15", }, + { "dbg:d16", }, + { "dbg:d17", }, + { "dbg:d18", }, + { "dbg:d19", }, +}; + +/* + * The triggers lines up below will only be used if the + * LED triggers are compiled in. + */ +static void dbg_led_set(struct led_classdev *cdev, + enum led_brightness b) +{ + struct dbg_led *led = container_of(cdev, struct dbg_led, cdev); + u16 reg; + + reg = readw_relaxed(&fpga->leds); + if (b != LED_OFF) + reg |= led->mask; + else + reg &= ~led->mask; + writew_relaxed(reg, &fpga->leds); +} + +static enum led_brightness dbg_led_get(struct led_classdev *cdev) +{ + struct dbg_led *led = container_of(cdev, struct dbg_led, cdev); + u16 reg; + + reg = readw_relaxed(&fpga->leds); + return (reg & led->mask) ? LED_FULL : LED_OFF; +} + +static int fpga_probe(struct platform_device *pdev) +{ + struct resource *iomem; + int i; + + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!iomem) + return -ENODEV; + + fpga = ioremap(iomem->start, resource_size(iomem)); + writew_relaxed(0xff, &fpga->leds); + + for (i = 0; i < ARRAY_SIZE(dbg_leds); i++) { + struct dbg_led *led; + + led = kzalloc(sizeof(*led), GFP_KERNEL); + if (!led) + break; + + led->cdev.name = dbg_leds[i].name; + led->cdev.brightness_set = dbg_led_set; + led->cdev.brightness_get = dbg_led_get; + led->cdev.default_trigger = dbg_leds[i].trigger; + led->mask = BIT(i); + + if (led_classdev_register(NULL, &led->cdev) < 0) { + kfree(led); + break; + } + } + + return 0; +} + +static int fpga_suspend_noirq(struct device *dev) +{ + fpga_led_state = readw_relaxed(&fpga->leds); + writew_relaxed(0xff, &fpga->leds); + + return 0; +} + +static int fpga_resume_noirq(struct device *dev) +{ + writew_relaxed(~fpga_led_state, &fpga->leds); + return 0; +} + +static const struct dev_pm_ops fpga_dev_pm_ops = { + .suspend_noirq = fpga_suspend_noirq, + .resume_noirq = fpga_resume_noirq, +}; + +static struct platform_driver led_driver = { + .driver.name = "omap_dbg_led", + .driver.pm = &fpga_dev_pm_ops, + .probe = fpga_probe, +}; + +static int __init fpga_init(void) +{ + if (machine_is_omap_h4() + || machine_is_omap_h3() + || machine_is_omap_h2() + || machine_is_omap_perseus2() + ) + return platform_driver_register(&led_driver); + return 0; +} +fs_initcall(fpga_init); |