#include <linux/version.h>
#include <linux/init.h>
#include <linux/kernel.h>    // printk()
#include <linux/module.h>    // THIS_MODULE
#include <linux/kobject.h>   // struct kobject
#include <linux/timer.h>
#include <linux/errno.h>     // error codes
#include <linux/sysfs.h>
#include <linux/syscalls.h>
#include <linux/workqueue.h>
#include <asm/ioctls.h>
#include <linux/spi/spidev.h>
#include "kfile.h"
#include "kspi.h"
#include "sfsattrib.h"

#define _TIMER_INTERVAL				(jiffies + 3 * HZ)

/////////////////////////////////////////////////////////////////////////////

MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("GfA");

/////////////////////////////////////////////////////////////////////////////

#define _SPI_DEVICE				"/dev/spidev1.0"

static void work_queue_func(struct work_struct *work);
static struct kobject *g_pKoGfa = NULL, *g_pKoTiva = NULL;

/////////////////////////////////////////////////////////////////////////////
// timer

static struct workqueue_struct *g_pwq = NULL;
static DECLARE_WORK(g_wo, work_queue_func);

static volatile bool g_bTimerRunning = false;
static struct timer_list g_jiq_timer;

static void OnJigTimer(unsigned long ptr)
{
//	printk(KERN_ALERT "%s, Ctx: \"%s\"-(%d)\n", __FUNCTION__, current->comm, current->pid);
	queue_work(g_pwq, &g_wo);
}

/////////////////////////////////////////////////////////////////////////////
// work queue
// sysfs_notify
// https://stackoverflow.com/questions/16367623/using-the-linux-sysfs-notify-call
//

static void work_queue_func(struct work_struct *work)
{
	TIVA_ADC tadc;
	struct file *pfSpiDev = NULL;
	uint8_t mode = SPI_MODE_3;
	uint8_t bits = 8;
	uint32_t speed = 1000000;
	unsigned long start = jiffies;

//	printk(KERN_ALERT "%s, Ctx: \"%s\"-(%d)\n", __FUNCTION__, current->comm, current->pid);
//	CmdGetFirmwareVersion(pfSpiDev, &g_hw, &g_sw);
//	sysfs_notify(g_pKoTiva, NULL, "firmware");

	if((pfSpiDev = kf_open(_SPI_DEVICE, O_RDWR, 0)))
	{
		if(kf_ioctl(pfSpiDev, SPI_IOC_WR_MODE, (unsigned long)&mode) < 0)
		{
			printk(KERN_ALERT "can't set spi mode\n");
//			break;
		}

		if(kf_ioctl(pfSpiDev, SPI_IOC_RD_MODE, (unsigned long)&mode) < 0)
		{
			printk(KERN_ALERT "can't get spi mode\n");
//			break;
		}

		/////////////////////////////////////////////////////////////////////

		if(kf_ioctl(pfSpiDev, SPI_IOC_WR_BITS_PER_WORD, (unsigned long)&bits) < 0)
		{
			printk(KERN_ALERT "can't set bits per word\n");
//			break;
		}

		if(kf_ioctl(pfSpiDev, SPI_IOC_RD_BITS_PER_WORD, (unsigned long)&bits) < 0)
		{
			printk(KERN_ALERT "can't get bits per word\n");
//			break;
		}

		/////////////////////////////////////////////////////////////////////

		if(kf_ioctl(pfSpiDev, SPI_IOC_WR_MAX_SPEED_HZ, (unsigned long)&speed) < 0)
		{
			printk(KERN_ALERT "can't set max speed hz\n");
//			break;
		}

		if(kf_ioctl(pfSpiDev, SPI_IOC_RD_MAX_SPEED_HZ, (unsigned long)&speed) < 0)
		{
			printk(KERN_ALERT "can't get max speed hz\n");
//			break;
		}

		if(CmdGetADC(pfSpiDev, &tadc) == 0)
		{
			if(g_tadc.UVers != tadc.UVers)
			{
				g_tadc.UVers = tadc.UVers;
				sysfs_notify(g_pKoTiva, NULL, "UVers");
//				printk(KERN_ALERT "Update UVers.\n");
			}
			
			if(g_tadc.UBatV3 != tadc.UBatV3)
			{
				g_tadc.UBatV3 = tadc.UBatV3;
				sysfs_notify(g_pKoTiva, NULL, "UBatV3");
//				printk(KERN_ALERT "Update UBatV3.\n");
			}
			
			if(g_tadc.Temp != tadc.Temp)
			{
				g_tadc.Temp = tadc.Temp;
				sysfs_notify(g_pKoTiva, NULL, "Temp");
//				printk(KERN_ALERT "Update Temp.\n");
			}
			
			if(g_tadc.UV5Vsys != tadc.UV5Vsys)
			{
				g_tadc.UV5Vsys = tadc.UV5Vsys;
				sysfs_notify(g_pKoTiva, NULL, "UV5Vsys");
//				printk(KERN_ALERT "Update UV5Vsys.\n");
			}
			
			if(g_tadc.UV3V6Bat != tadc.UV3V6Bat)
			{
				g_tadc.UV3V6Bat = tadc.UV3V6Bat;
				sysfs_notify(g_pKoTiva, NULL, "UV3V6Bat");
//				printk(KERN_ALERT "Update UV3V6Bat.\n");
			}
			
			if(g_tadc.TempTIVA != tadc.TempTIVA)
			{
				g_tadc.TempTIVA = tadc.TempTIVA;
				sysfs_notify(g_pKoTiva, NULL, "TempTIVA");
//				printk(KERN_ALERT "Update TempTIVA.\n");
			}
		}

		kf_close(pfSpiDev);
	}
	else
	{
		printk(KERN_ALERT "file_open failed\n");
	}

	if(g_bTimerRunning)
	{
		mod_timer(&g_jiq_timer, _TIMER_INTERVAL);
	}
	
	printk(KERN_ALERT "Worker pass jiffies: %lu\n", ((long)jiffies - (long)start));
}

/////////////////////////////////////////////////////////////////////////////

static int drv_init(void)
{
	/////////////////////////////////////////////////////////////////////////

	do
	{
		if(!(g_pKoGfa = kobject_create_and_add("gfa", NULL)))
		{
			printk(KERN_ALERT "kobject_create_and_add failed\n");
			break;
		}

		if(!(g_pKoTiva = kobject_create_and_add("tiva", g_pKoGfa)))
		{
			printk(KERN_ALERT "kobject_create_and_add failed\n");
			break;
		}

		/////////////////////////////////////////////////////////////////////

		if(sysfs_create_file(g_pKoTiva, &g_tivaFirmwareAtt.attr))
		{
			printk(KERN_ALERT "sysfs_create_file failed\n");
			break;
		}

		if(sysfs_create_file(g_pKoTiva, &g_tivaUVersAtt.attr))
		{
			printk(KERN_ALERT "sysfs_create_file failed\n");
			break;
		}

		if(sysfs_create_file(g_pKoTiva, &g_tivaUBatV3Att.attr))
		{
			printk(KERN_ALERT "sysfs_create_file failed\n");
			break;
		}

		if(sysfs_create_file(g_pKoTiva, &g_tivaTempAtt.attr))
		{
			printk(KERN_ALERT "sysfs_create_file failed\n");
			break;
		}

		if(sysfs_create_file(g_pKoTiva, &g_tivaUV5VsysAtt.attr))
		{
			printk(KERN_ALERT "sysfs_create_file failed\n");
			break;
		}

		if(sysfs_create_file(g_pKoTiva, &g_tivaUV3V6BatAtt.attr))
		{
			printk(KERN_ALERT "sysfs_create_file failed\n");
			break;
		}

		if(sysfs_create_file(g_pKoTiva, &g_tivaTempTIVAAtt.attr))
		{
			printk(KERN_ALERT "sysfs_create_file failed\n");
			break;
		}

		/////////////////////////////////////////////////////////////////////

		if(!(g_pwq = create_workqueue("GfaWrk")))
		{
			printk(KERN_ALERT "create_workqueue failed!\n");
			break;
		}

		/////////////////////////////////////////////////////////////////////

		init_timer(&g_jiq_timer);
		g_jiq_timer.function = OnJigTimer;
		g_jiq_timer.data = 0;
		g_jiq_timer.expires = _TIMER_INTERVAL;
		add_timer(&g_jiq_timer);
		g_bTimerRunning = true;

		/////////////////////////////////////////////////////////////////////

		if(!queue_work(g_pwq, &g_wo))
		{
			printk(KERN_ALERT "queue_work failed\n");
			break;
		}

		/////////////////////////////////////////////////////////////////////

		printk(KERN_ALERT "%s, Ctx: \"%s\"-(%d)\n", __FUNCTION__, current->comm, current->pid);
		return 0;
	}
	while(0);

	/////////////////////////////////////////////////////////////////////////
	
	if(g_bTimerRunning)
	{
		g_bTimerRunning = false;
		del_timer_sync(&g_jiq_timer);
	}

	if(g_pwq)
		destroy_workqueue(g_pwq);                           

	if(g_pKoTiva)
	{
		sysfs_remove_file(g_pKoTiva, &g_tivaFirmwareAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUVersAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUBatV3Att.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaTempAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUV5VsysAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUV3V6BatAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaTempTIVAAtt.attr);
		kobject_put(g_pKoTiva);
		g_pKoTiva = NULL;
	}

	if(g_pKoGfa)
	{
		kobject_put(g_pKoGfa);
		g_pKoGfa = NULL;
	}

	return -ENOMEM;
}

/////////////////////////////////////////////////////////////////////////////

static void drv_exit(void)
{
	g_bTimerRunning = false;
	del_timer_sync(&g_jiq_timer);

	if(g_pwq)
		destroy_workqueue(g_pwq);                           

	if(g_pKoTiva)
	{
		sysfs_remove_file(g_pKoTiva, &g_tivaFirmwareAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUVersAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUBatV3Att.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaTempAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUV5VsysAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaUV3V6BatAtt.attr);
		sysfs_remove_file(g_pKoTiva, &g_tivaTempTIVAAtt.attr);
		kobject_put(g_pKoTiva);
	}

	if(g_pKoGfa)
		kobject_put(g_pKoGfa);

	printk(KERN_ALERT "%s, Ctx: \"%s\"-(%d)\n", __FUNCTION__, current->comm, current->pid);
}

/////////////////////////////////////////////////////////////////////////////

module_init(drv_init);
module_exit(drv_exit);