/*
 * LED Class Core
 *
 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
 * Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
 *
 * 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/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/sysdev.h>
#include <linux/timer.h>
#include <linux/err.h>
#include <linux/ctype.h>
#include <linux/leds.h>
#include <linux/errno.h>
#include "leds.h"

#define   MAX_USERS          32
#define   N_COLORS           4
#define   N_EVENTS            3
#define   USR_LEN            81
#define   EVENT_LEN          81
#define   INDEX_LEN          8


/* LED users */
#define   EV_NAS_SYSTEM      0    /* Overall system: NAS ready, booting, shutdown... */
#define   EV_DISK_SMART      1    /* Disk SMART including temp., error lba, ...*/
#define   EV_DISK_IO         2    /* Disk read/write error */
#define   EV_RAID_CFG        3    /* RAID setup failure: assembling, formatting, rebuild ...*/
#define   EV_FW_UPDATE       4    /* NAS firmware update */
#define   EV_NETWORK         5    /* Network connectivity error */
#define   EV_VM              6    /* Volume manager */

char Led_user_arr[MAX_USERS][USR_LEN] = { "EV_NAS_SYSTEM", \
                                          "EV_DISK_SMART", \
                                          "EV_DISK_IO"   , \
                                          "EV_RAID_CFG"  , \
                                          "EV_FW_UPDATE" , \
                                          "EV_NETWORK"   , \
                                          "EV_VM",         \
                                        };
/* LED event types */
#define   LED_STAT_OK        0    /* Happy user, normal operation */
#define   LED_STAT_ERR       1    /* User error, needs led indication */
#define   LED_STAT_IN_PROG   2    /* User doing something important, needs led indication */

char *Led_ev_arr[] = { "LED_STAT_OK", "LED_STAT_ERR", "LED_STAT_IN_PROG" };

char Color_map[MAX_USERS][N_EVENTS]  = { {'g','r','w'}, /* EV_NAS_SYSTEM */ \
                                         {'g','y','w'}, /* EV_DISK_SMART */ \
                                         {'g','r','w'}, /* EV_DISK_IO    */ \
                                         {'g','r','w'}, /* EV_RAID_CFG   */ \
                                         {'g','r','w'}, /* EV_FW_UPDATE  */ \
                                         {'g','y','w'}, /* EV_NETWORK    */ \
                                         {'g','r','w'}, /* EV_VM */ \
                                       };

char Blink_map[MAX_USERS][N_EVENTS]  = { {'n','n','n'}, /* EV_NAS_SYSTEM */ \
                                         {'n','y','n'}, /* EV_DISK_SMART */ \
                                         {'n','n','n'}, /* EV_DISK_IO    */ \
                                         {'n','n','n'}, /* EV_RAID_CFG   */ \
                                         {'n','n','n'}, /* EV_FW_UPDATE  */ \
                                         {'n','y','n'}, /* EV_NETWORK    */ \
                                         {'n','n','n'}, /* EV_VM */ \
                                       };

u32  Led_error_bits = 0;
int  N_USERS = 7;    /* default number of users */

static struct class *leds_class;

static void led_update_color(struct led_classdev *led_cdev)
{
    if (led_cdev->color_get)
        led_cdev->color = led_cdev->color_get(led_cdev);
}

static ssize_t led_color_store(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t size)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);
    unsigned long state = 9;
    char user[USR_LEN], event[EVENT_LEN], index_str[INDEX_LEN], color;
    int i = 0, j = 0, found = 0, tmp = 0, edit_policy = 0;
    int reg_user = -1, reg_event = -1, reg_color = -1;
    const char * cptr = NULL;
    long int index = -1;
    char blink;
    int reg_blink = 'n';
        
    cptr = &buf[0];

    /* check for 'register' event */
    // NB: Format of register event is 
    // register:event,status,color
    if( cptr[8] == ':' ) {
       if( !memcmp("register", cptr, 8) ) {
          edit_policy = 1;
          cptr = &buf[9];
       }
    }

    /* parse user name */ 
    for( i = 0; i < (USR_LEN -1) && cptr[i]; i++ ) {
       if( cptr[i] == ',' ) {
           break;
       }
       user[i] = cptr[i];
    }

    /* null terminate user buf */
    user[i] = '\0';
    i++; /* skips the ',' delimiter */


    for( j = 0; (j < EVENT_LEN -1) && cptr[i] ; j++,i++ ) {
       if( (cptr[i] == ',') || (cptr[i] == '\0') || (cptr[i] == '\n') ) {
          if( cptr[i] == ',' ) {
              cptr = &cptr[i+1];
          }
          break;
       }
       event[j] = cptr[i];
    }
    /* null terminate event buf */
    event[j] = '\0';
    
    /* if editing policy, parse the color */ 
    if( edit_policy ) {
       if( cptr != NULL ) {
         reg_color = cptr[0];  /* r,g,b,y,w */
         if( reg_color != 'r' && reg_color != 'g' && 
             reg_color != 'b' && reg_color != 'y' && reg_color != 'w' ) {
             reg_color = -1;  /* invalid color */               
         }

        /** TBD: Get the value of reg_blink from cptr */
       }
    }
    else { 
       /* scan index for some users */
       if( !strcmp(user, Led_user_arr[EV_DISK_SMART]) || 
           !strcmp(user, Led_user_arr[EV_DISK_IO]) ) {
          if( cptr != NULL ) {
             for( i = 0; (i < INDEX_LEN -1) && cptr[i] ; i++ ) {
                if( (cptr[i] == ',') || (cptr[i] == '\0') || (cptr[i] == '\n') ) {
                   break;
                }
                index_str[i] = cptr[i];
             }
          }
       }
    
       /* null terminate index_str */
       index_str[i] = '\0';
       if( i ) {
          tmp = strict_strtol(index_str, 10, &index);
          if( !tmp && (index >= 0) ) {
             /*
              * TODO: insert code to fulfill req's. Currently not required.
              */
             /*printk(KERN_INFO "\nindex %ld\n", index);*/
          }
       }
    } /* if( !edit_policy ) */

    /* Validate user and event */
    found = 0; 
    for( i = 0; i < N_USERS; i++ ) {
        if( !strcmp( Led_user_arr[i], user ) ) {
            found = 1;
            break;
        }
    }
 
    if( found || edit_policy) {
        reg_user = i;
        /* new user registration */
        if( ! found ) {
            if( N_USERS == MAX_USERS ) {
                /* only support up to 32 users */
                return (ssize_t)size;
            }
            reg_user = N_USERS++;
         
            strcpy(Led_user_arr[reg_user], user);
        }
        found = 0;
        for( j = 0; j < N_EVENTS; j++ ) {
            if( ! strcmp(Led_ev_arr[j], event) ) {
                if( j == LED_STAT_ERR ) {
                    Led_error_bits |= (1 << i); /* register error for this user */
                }
                else if( j == LED_STAT_OK ) {
                    Led_error_bits &= ~(1 << i); /* clear error for this user */
                }
                found = 1;
                reg_event = j;
                break;
            }
        }
    }

    /* if this is a register event, do just that */
    if( edit_policy ) {
        /* valid event above and color */
        if( (reg_event != -1) && (reg_color != -1) ) {
            Color_map[reg_user][reg_event] = reg_color;

            /** TBD: Add support for registering blink with register: interface*/
            reg_blink = 'n';
            Blink_map[reg_user][reg_event] = reg_blink;
        }
        /*printk( KERN_INFO "reg_user = %d, reg_event= %d, reg_color = %c\n", reg_user, reg_event, reg_color, reg_blink);*/
        return (ssize_t)size;
    }

    /* Be nice ! support older led mechanism */ 
    color = buf[0];
    blink = 'x';

    /* If valid user and event, retrieve color & blink map */
    if( found ) {
        /* if a canceling event and other error(s) existing, don't do anything */
        if( (j == LED_STAT_OK) && (Led_error_bits != 0) ) {
        }
        else {
            color = Color_map[i][j];
            blink = Blink_map[i][j];
        }
        /*printk(KERN_INFO "\nUser= %s, event= %s, color %c, %08x\n", user, event, color, blink, Led_error_bits);*/
    }       

    switch (color) {
        case 'r': /* red */
            state = 1;
            break;
        case 'g': /* green */
            state = 2;
            break;
        case 'b': /* blue */
            state = 3;
            break;
        case 'y': /* yellow */
            state = 4;
            break;
        case 'w': /* white */
            state = 5;
            break;
        case 'o': /* off */
            state = 0;
            break;
        default:
			state = -1;
            break;
    }

	/** do nothing if no color change is required */
	if( state == -1 ) {
	    return (ssize_t)size;
	}

	// printk(KERN_DEBUG "Calling led_set_color with value %c, blink is %c\n", color, blink);
	led_set_color( led_cdev, state );

    /** blink the led */
    {
        int val = -1;

        printk(KERN_DEBUG "Calling led_set_blink with value %c\n", blink);

		switch( blink ) {
            case 'y':	/** yes */
				val = 1;
				break;
            case 'n':	/** no */
				val = 0;
				break;
            case 'f':	/** forced */
				val = 2;
				break;
			default:
				break;
		}

        if( val >= 0 )
        {
            led_set_blink( led_cdev, val );
        }
    }

    return (ssize_t)size;
}

static ssize_t led_color_show(struct device *dev, 
        struct device_attribute *attr, char *buf) {

    struct led_classdev *led_cdev = dev_get_drvdata(dev);
        char * readbuf[] = {"off", "red", "green", "blue", "yellow", "white"} ;
    /* no lock needed for this */
    led_update_color(led_cdev);

    return sprintf(buf, "%s\n", readbuf[led_cdev->color]);
}

static ssize_t led_blink_show(struct device *dev, struct device_attribute *attr,
                                                  char *buf) {
        char *blinkStr = "no";
        struct led_classdev  *led_cdev = dev_get_drvdata(dev);
        
        if( led_cdev->blink == 0 ){ 
           blinkStr = "no";        
        } 
        else if (led_cdev->blink == 1 ){
           blinkStr = "yes";
        }
    return sprintf(buf, "%s\n", blinkStr);
}

static ssize_t led_blink_store(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t size) {
        int val = 0;
        struct led_classdev * led_cdev = dev_get_drvdata(dev);
 
        if( buf[0] == 'y' ) {
           val = 1;
        }
        else if( buf[0] == 'n' ) {
           val = 0;
        }
        else if( buf[0] == 'f' ) {
           val = 2;
        }
        led_set_blink( led_cdev, val );

        return (ssize_t)size;
}

static ssize_t led_max_brightness_show(struct device *dev,
        struct device_attribute *attr, char *buf)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);

    return sprintf(buf, "%u\n", led_cdev->max_brightness);
}

/*static DEVICE_ATTR(brightness, 0644, led_brightness_show, led_brightness_store);*/
static DEVICE_ATTR(color, 0644, led_color_show, led_color_store);
static DEVICE_ATTR(blink, 0644, led_blink_show, led_blink_store);
static DEVICE_ATTR(max_brightness, 0444, led_max_brightness_show, NULL);
#ifdef CONFIG_LEDS_TRIGGERS
static DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
#endif

/**
 * led_classdev_suspend - suspend an led_classdev.
 * @led_cdev: the led_classdev to suspend.
 */
void led_classdev_suspend(struct led_classdev *led_cdev)
{
    led_cdev->flags |= LED_SUSPENDED;
    led_cdev->color_set(led_cdev, 0);
}
EXPORT_SYMBOL_GPL(led_classdev_suspend);

/**
 * led_classdev_resume - resume an led_classdev.
 * @led_cdev: the led_classdev to resume.
 */
void led_classdev_resume(struct led_classdev *led_cdev)
{
    led_cdev->color_set(led_cdev, led_cdev->color);
    led_cdev->flags &= ~LED_SUSPENDED;
}
EXPORT_SYMBOL_GPL(led_classdev_resume);

static int led_suspend(struct device *dev, pm_message_t state)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);

    if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
        led_classdev_suspend(led_cdev);

    return 0;
}

static int led_resume(struct device *dev)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);

    if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
        led_classdev_resume(led_cdev);

    return 0;
}

/**
 * led_classdev_register - register a new object of led_classdev class.
 * @parent: The device to register.
 * @led_cdev: the led_classdev structure for this device.
 */
int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
{
    int rc;

    led_cdev->dev = device_create(leds_class, parent, 0, led_cdev,
                      "%s", led_cdev->name);
    if (IS_ERR(led_cdev->dev))
        return PTR_ERR(led_cdev->dev);

    /* register the attributes */
    rc = device_create_file(led_cdev->dev, &dev_attr_color);
    if (rc)
        goto err_out;

    rc = device_create_file(led_cdev->dev, &dev_attr_blink);
    if (rc)
        goto err_out;

#ifdef CONFIG_LEDS_TRIGGERS
    init_rwsem(&led_cdev->trigger_lock);
#endif
    /* add to the list of leds */
    down_write(&leds_list_lock);
    list_add_tail(&led_cdev->node, &leds_list);
    up_write(&leds_list_lock);

    if (!led_cdev->max_brightness)
        led_cdev->max_brightness = LED_FULL;

    rc = device_create_file(led_cdev->dev, &dev_attr_max_brightness);
    if (rc)
        goto err_out_attr_max;

    led_update_color(led_cdev);

#ifdef CONFIG_LEDS_TRIGGERS
    rc = device_create_file(led_cdev->dev, &dev_attr_trigger);
    if (rc)
        goto err_out_led_list;

    led_trigger_set_default(led_cdev);
#endif

    printk(KERN_INFO "Registered led device: %s\n",
            led_cdev->name);

    return 0;

#ifdef CONFIG_LEDS_TRIGGERS
err_out_led_list:
    device_remove_file(led_cdev->dev, &dev_attr_max_brightness);
#endif
err_out_attr_max:
    device_remove_file(led_cdev->dev, &dev_attr_color);
    list_del(&led_cdev->node);
err_out:
    device_unregister(led_cdev->dev);
    return rc;
}
EXPORT_SYMBOL_GPL(led_classdev_register);

/**
 * led_classdev_unregister - unregisters a object of led_properties class.
 * @led_cdev: the led device to unregister
 *
 * Unregisters a previously registered via led_classdev_register object.
 */
void led_classdev_unregister(struct led_classdev *led_cdev)
{
    device_remove_file(led_cdev->dev, &dev_attr_max_brightness);
    device_remove_file(led_cdev->dev, &dev_attr_color);
#ifdef CONFIG_LEDS_TRIGGERS
    device_remove_file(led_cdev->dev, &dev_attr_trigger);
    down_write(&led_cdev->trigger_lock);
    if (led_cdev->trigger)
        led_trigger_set(led_cdev, NULL);
    up_write(&led_cdev->trigger_lock);
#endif

    device_unregister(led_cdev->dev);

    down_write(&leds_list_lock);
    list_del(&led_cdev->node);
    up_write(&leds_list_lock);
}
EXPORT_SYMBOL_GPL(led_classdev_unregister);

static int __init leds_init(void)
{
    leds_class = class_create(THIS_MODULE, "leds");
    if (IS_ERR(leds_class))
        return PTR_ERR(leds_class);
    leds_class->suspend = led_suspend;
    leds_class->resume = led_resume;
    return 0;
}

static void __exit leds_exit(void)
{
    class_destroy(leds_class);
}

subsys_initcall(leds_init);
module_exit(leds_exit);

MODULE_AUTHOR("John Lenz, Richard Purdie");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LED Class Interface");