--- ./drivers/char/led.c.led Fri Jan 25 09:36:27 2002
+++ ./drivers/char/led.c Fri Jan 25 11:03:22 2002
@@ -0,0 +1,316 @@
+/*
+ * Device driver for controlling LEDs. See linux/led.h for info on
+ * how to use this.
+ *
+ * This currently only supports mono and bicolor LEDs, but support for
+ * fancier LEDs (scrolling text or numeric LEDs, for instance) could
+ * easily be added.
+ *
+ * Corey Minyard <[email protected]>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/init.h>
+#include <linux/led.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+
+#define VERSION "1.0"
+
+/* A lock that is held when manipulating LED info. */
+static spinlock_t led_lock;
+
+/* A linked list of all the LEDs registered. */
+static struct led_reg_info *leds;
+
+/* Register a new LED with the driver. */
+int register_led_info(struct led_reg_info *info)
+{
+ struct led_reg_info *led;
+ int rv = 0;
+
+ spin_lock(&led_lock);
+ info->next = NULL;
+ led = leds;
+ if (led == NULL)
+ {
+ leds = info;
+ }
+ else
+ {
+ while (led->next != NULL)
+ {
+ if (strcmp(led->info->name, info->info->name) == 0)
+ {
+ /* Registering a duplicate. */
+ rv = -1;
+ goto out;
+ }
+ led = led->next;
+ }
+ led->next = info;
+ }
+ MOD_INC_USE_COUNT;
+
+out:
+ spin_unlock(&led_lock);
+
+ return rv;
+}
+
+/* Unregister an LED from the driver. */
+int unregister_led_info(struct led_reg_info *info)
+{
+ int rv = -1;
+ struct led_reg_info *led;
+
+ if (info == NULL)
+ {
+ return -1;
+ }
+
+ spin_lock(&led_lock);
+ led = leds;
+ if (led == info)
+ {
+ MOD_DEC_USE_COUNT;
+ leds = leds->next;
+ }
+ else
+ {
+ while (led->next != NULL)
+ {
+ if (led->next == info)
+ {
+ MOD_DEC_USE_COUNT;
+ led->next = info->next;
+ rv = 0;
+ goto out;
+ }
+ led = led->next;
+ }
+ }
+out:
+ spin_unlock(&led_lock);
+ return rv;
+}
+
+/* Return the number of LEDs registered. */
+static int count_leds(void)
+{
+ struct led_reg_info *led;
+ int count = 0;
+
+ spin_lock(&led_lock);
+ led = leds;
+ while (led != NULL)
+ {
+ count = count + 1;
+ led = led->next;
+ }
+ spin_unlock(&led_lock);
+
+ return count;
+}
+
+/* Find an LED by its number. Must be called with the led spin lock
+ held. */
+static struct led_reg_info *get_led_by_num(int num)
+{
+ struct led_reg_info *led;
+ int count = num;
+
+ led = leds;
+ while (led != NULL)
+ {
+ if (count == 0)
+ {
+ led->info->led_num = num;
+ return led;
+ }
+ count = count - 1;
+ led = led->next;
+ }
+
+ return NULL;
+}
+
+/* Find an LED by its name. Must be called with the led spin lock
+ held. */
+static struct led_reg_info *get_led_by_name(char *name)
+{
+ struct led_reg_info *led;
+ int count = 0;
+
+ led = leds;
+ while (led != NULL)
+ {
+ if (strcmp(name, led->info->name) == 0)
+ {
+ led->info->led_num = count;
+ return led;
+ }
+ count++;
+ led = led->next;
+ }
+
+ return NULL;
+}
+
+/* The IOCTL handler for the LED driver. */
+static int led_ioctl(struct inode *inode,
+ struct file *file,
+ unsigned int cmd,
+ unsigned long arg)
+{
+ int i;
+ struct led_reg_info *led;
+ struct led_info info;
+ struct led_op op;
+
+ switch(cmd)
+ {
+ case LEDIOC_GETCOUNT:
+ return count_leds();
+
+ case LEDIOC_GETINFO_BY_NUM:
+ case LEDIOC_GETINFO_BY_NAME:
+ i = copy_from_user(&info, (void*)arg, sizeof(info));
+ if (i)
+ {
+ return -EFAULT;
+ }
+
+ spin_lock(&led_lock);
+ if (cmd == LEDIOC_GETINFO_BY_NUM)
+ led = get_led_by_num(info.led_num);
+ else
+ led = get_led_by_name(info.name);
+ if (led == NULL)
+ {
+ spin_unlock(&led_lock);
+ return -EINVAL;
+ }
+
+ info.type = led->info->type;
+ info.led_num = led->info->led_num;
+ strcpy(info.name, led->info->name);
+ info.info = led->info->info;
+ i = copy_to_user((void *)arg, &info, sizeof(info));
+
+ spin_unlock(&led_lock);
+
+ if (i)
+ {
+ return -EFAULT;
+ }
+ return 0;
+
+ case LEDIOC_OP:
+ i = copy_from_user(&op, (void*)arg, sizeof(op));
+ if (i)
+ {
+ return -EFAULT;
+ }
+
+ spin_lock(&led_lock);
+ led = get_led_by_name(op.name);
+ if (led == NULL)
+ {
+ spin_unlock(&led_lock);
+ return -EINVAL;
+ }
+
+ i = led->handle_led_op(led, &op);
+ if (!i)
+ {
+ i = copy_to_user((void *)arg, &op, sizeof(op));
+ if (i)
+ {
+ i = -EFAULT;
+ }
+ }
+ spin_unlock(&led_lock);
+
+ return i;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+/* Not much to do for opening. */
+static int led_open(struct inode *inode, struct file *file)
+{
+ switch(MINOR(inode->i_rdev))
+ {
+ case LED_MINOR:
+ return 0;
+
+ default:
+ return -ENODEV;
+ }
+}
+
+/* Closing is really easy. */
+static int led_close(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+
+
+static struct file_operations led_fops = {
+ owner: THIS_MODULE,
+ llseek: NULL,
+ read: NULL,
+ write: NULL,
+ ioctl: led_ioctl,
+ open: led_open,
+ release: led_close,
+};
+
+static struct miscdevice led_miscdev=
+{
+ LED_MINOR,
+ "led",
+ &led_fops
+};
+
+
+/* Remove the LED driver. */
+static void __exit led_exit(void)
+{
+ misc_deregister(&led_miscdev);
+}
+
+/* Set up the LED device driver. */
+static int __init led_init(void)
+{
+ int ret;
+
+ printk("generic LED driver: v%s Corey Minyard ([email protected])\n",
+ VERSION);
+
+ leds = NULL;
+ ret = misc_register(&led_miscdev);
+ if (ret) {
+ printk(KERN_ERR "led: can't misc_register on minor=%d\n",
+ LED_MINOR);
+ return -1;
+ }
+ return 0;
+}
+
+module_init(led_init);
+module_exit(led_exit);
+
+EXPORT_SYMBOL(register_led_info);
+EXPORT_SYMBOL(unregister_led_info);
--- ./drivers/char/Config.in.led Fri Jan 25 10:33:28 2002
+++ ./drivers/char/Config.in Fri Jan 25 11:03:22 2002
@@ -222,6 +222,8 @@
fi
endmenu
+tristate 'LED device driver support' CONFIG_LINUX_LED
+
if [ "$CONFIG_ARCH_NETWINDER" = "y" ]; then
tristate 'NetWinder thermometer support' CONFIG_DS1620
tristate 'NetWinder Button' CONFIG_NWBUTTON
--- ./drivers/char/Makefile.led Fri Jan 25 09:36:27 2002
+++ ./drivers/char/Makefile Fri Jan 25 11:03:22 2002
@@ -24,7 +24,7 @@
export-objs := busmouse.o console.o keyboard.o sysrq.o \
misc.o pty.o random.o selection.o serial.o \
sonypi.o tty_io.o tty_ioctl.o generic_serial.o \
- ppc405_gpio.o au1000_gpio.o lcd.o \
+ ppc405_gpio.o au1000_gpio.o lcd.o led.o \
h3600_backpaq_fpga.o
mod-subdirs := joystick ftape drm pcmcia
@@ -250,6 +250,7 @@
obj-$(CONFIG_ITE_GPIO) += ite_gpio.o
obj-$(CONFIG_AU1000_GPIO) += au1000_gpio.o
obj-$(CONFIG_PPC405_GPIO) += ppc405_gpio.o
+obj-$(CONFIG_LINUX_LED) += led.o
obj-$(CONFIG_QIC02_TAPE) += tpqic02.o
--- ./Documentation/Configure.help.led Fri Jan 25 11:02:12 2002
+++ ./Documentation/Configure.help Fri Jan 25 11:03:22 2002
@@ -11578,6 +11578,12 @@
then also Y to the driver for your FDDI card, below). Most people
will say N.
+Linux LED Support
+CONFIG_LINUX_LED
+ This is a driver that supports controlling LEDs. It is a generic
+ driver that provides a control framework, the actual drivers must
+ register with it to work.
+
Digital DEFEA and DEFPA adapter support
CONFIG_DEFXX
This is support for the DIGITAL series of EISA (DEFEA) and PCI
--- ./include/linux/led.h.led Fri Jan 25 09:36:27 2002
+++ ./include/linux/led.h Fri Jan 25 11:03:22 2002
@@ -0,0 +1,130 @@
+/*
+ * Defines for the LED device driver.
+ *
+ * This driver uses ioctl() calls to get information about the LEDS
+ * and to set their values.
+ *
+ * This currently only supports mono and bicolor LEDs, but support for
+ * fancier LEDs (scrolling text or numeric LEDs, for instance) could
+ * easily be added.
+ *
+ * Corey Minyard <[email protected]>
+ *
+ */
+
+#ifndef _LINUX_LED_H
+#define _LINUX_LED_H
+
+#include <linux/ioctl.h>
+
+#define LED_IOCTL_BASE 'L'
+
+/* Types of LEDs. */
+#define LED_TYPE_MONOCOLOR 1
+#define LED_TYPE_BICOLOR 2
+
+/* Defines for LED colors. */
+#define LED_COLOR_OFF 0
+#define LED_COLOR_RED 1
+#define LED_COLOR_GREEN 2
+#define LED_COLOR_BLUE 3
+#define LED_COLOR_YELLOW 4
+#define LED_COLOR_AUXMODE -1 /* Set it to the auxiliary mode. */
+
+union led_info_u
+{
+ struct
+ {
+ int color; /* Color of the LED. */
+ int has_aux_mode; /* If true, the LED has an auxiliary
+ mode (like a disk drive or
+ network LED) that it can be set
+ to work in. */
+ } monocolor;
+
+ struct
+ {
+ int color1; /* First color of the LED. */
+ int color2; /* Second color of the LED. */
+ int has_aux_mode; /* If true, the LED has an auxiliary
+ mode (like a disk drive or
+ network LED) that it can be set
+ to work in. */
+ } bicolor;
+};
+
+/* Information about an LED. This is not the dynamic information, but
+ the information about the capabilities of the LED. */
+struct led_info
+{
+ int led_num;
+ int type;
+ char name[32]; /* The name of the LED, used to address it. */
+ union led_info_u info;
+};
+
+/* Operation types that are valid. */
+#define SET_LED 1 /* Set the value of the LED. */
+#define GET_LED 2 /* Return the LED's current value. */
+
+/* Operations defined for each different type of LED. */
+union led_op_u
+{
+ struct
+ {
+ int color;
+ } monocolor;
+
+ struct
+ {
+ int color;
+ } bicolor;
+};
+
+/* An operation to perform on the LED. Set the name and the operation
+ and any needed info and do an LEDIOC_OP ioctl. */
+struct led_op
+{
+ int op;
+ char name[32]; /* The name of the LED, used to address it. */
+ union led_op_u op_info;
+};
+
+
+
+/* Return the number of LEDs that have registered with the driver. */
+#define LEDIOC_GETCOUNT _IOR(LED_IOCTL_BASE, 0, void)
+
+/* Get the info for a single LED, indexed by number or name. */
+#define LEDIOC_GETINFO_BY_NUM _IOR(LED_IOCTL_BASE, 1, struct led_info)
+#define LEDIOC_GETINFO_BY_NAME _IOR(LED_IOCTL_BASE, 2, struct led_info)
+
+/* Perform an operation on single LED, indexed by name. */
+#define LEDIOC_OP _IOR(LED_IOCTL_BASE, 3, struct led_op)
+
+
+
+/* This is the structure that is registered with the LED driver by the
+ subtending LED drivers. One of these must be registered for each
+ LED. */
+struct led_reg_info
+{
+ struct led_info *info; /* Pointer to the info structure for
+ this LED. */
+ void *data; /* Used by the specific LED driver for
+ whatever it likes. */
+
+ /* The handler the driver supplies to handle operations. */
+ int (*handle_led_op)(struct led_reg_info *info,
+ struct led_op *op);
+
+ struct led_reg_info *next;
+};
+
+/* Add an LED to the set of LEDs the driver controls. */
+int register_led_info(struct led_reg_info *info);
+
+/* Remove an LED from the set of LEDs the driver controls. */
+int unregister_led_info(struct led_reg_info *info);
+
+#endif /* ifndef _LINUX_LED_H */
--- ./include/linux/miscdevice.h.led Fri Jan 25 11:00:55 2002
+++ ./include/linux/miscdevice.h Fri Jan 25 11:03:22 2002
@@ -15,6 +15,7 @@
#define ADB_MOUSE_MINOR 10
#define WATCHDOG_MINOR 130 /* Watchdog timer */
#define TEMP_MINOR 131 /* Temperature Sensor */
+#define LED_MINOR 132 /* LED device driver */
#define RTC_MINOR 135
#define EFI_RTC_MINOR 136 /* EFI Time services */
#define SUN_OPENPROM_MINOR 139
> A lot of boards have LEDs on the front, it is useful to be able to
> control these LEDs from userland. I have implemented a start at a
> device driver front-end for this that gives a generic interface. I'd
> appreciate comments on it. I have not tied things like the num lock
> LEDs to this, but that might be doable later.
At a look at the input api (include/linux/input.h). Since keyboards have
leds we implemented a very basic api for this.