C180_oyster_driver/light_ring.c

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/i2c.h>
#include <linux/acpi.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/poll.h>
#include <linux/mutex.h>
#include <linux/delay.h>


#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/workqueue.h>

#define PCA9685_ADDR 0x40

#define PCA9685_DEFAULT_ADDR 0x40
#define PCA9685_GENERAL_CALL 0x00

#define PCA9685_MODE1 0x00
#define PCA9685_MODE2 0x01
#define PCA9685_SUBADR1 0x02
#define PCA9685_SUBADR2 0x03
#define PCA9685_SUBADR3 0x04
#define PCA9685_ALLCALLADR 0x05
#define PCA9685_LED0_ON_L 0x06
#define PCA9685_LED0_ON_H 0x07
#define PCA9685_LED0_OFF_L 0x08
#define PCA9685_LED0_OFF_H 0x09
#define PCA9685_ALL_LED_ON_L 0xFA
#define PCA9685_ALL_LED_ON_H 0xFB
#define PCA9685_ALL_LED_OFF_L 0xFC
#define PCA9685_ALL_LED_OFF_H 0xFD
#define PCA9685_PRESCALE 0xFE
#define PCA9685_TESTMODE 0xFF

#define MODE1_RESTART 0x80
#define MODE1_EXTCLK 0x40
#define MODE1_AI 0x20
#define MODE1_SLEEP 0x10
#define MODE1_SUB1 0x08
#define MODE1_SUB2 0x04
#define MODE1_SUB3 0x02
#define MODE1_ALLCALL 0x01

#define MODE2_INVRT 0x10
#define MODE2_OCH 0x08
#define MODE2_OUTDRV 0x04
#define MODE2_OUTNE1 0x02
#define MODE2_OUTNE0 0x01

#define PCA9685_PWM_RESOLUTION 4096
#define PCA9685_OSC_FREQ 25000000
#define PCA9685_MIN_FREQ 24
#define PCA9685_MAX_FREQ 1526


#define PCA9685_OK              0
#define PCA9685_ERR_OPEN       -1
#define PCA9685_ERR_ADDR       -2
#define PCA9685_ERR_WRITE      -3
#define PCA9685_ERR_READ       -4
#define PCA9685_ERR_PARAM      -5
#define PCA9685_ERR_INIT       -6


#define COLOR_RED 0xff0000     //{255, 0, 0}
#define COLOR_GREEN 0x00ff00   //{0, 255, 0}
#define COLOR_BLUE 0x0000ff    //{0, 0, 255}
#define COLOR_WHITE 0xffffff   //{255, 255, 255}
#define COLOR_FUCHSIA 0xff00ff //{255, 0, 255}
#define COLOR_YELLOW 0xffff00  //{255, 255, 0}
#define COLOR_CYAN 0x00ffff    //{0, 255, 255}

#define LIGHT_MODE_OFF  0x01
#define LIGHT_MODE_ON   0x02
#define LIGHT_MODE_FLASH_1SEC 0x03
#define LIGHT_MODE_FLASH_2SEC 0x04
#define LIGHT_MODE_FLASH_3SEC 0x05
#define LIGHT_MODE_FLASH_SLOW 0x06
#define LIGHT_MODE_FLASH_MEDIUM 0x07
#define LIGHT_MODE_FLASH_FAST 0x08

struct lightring_data
{
    u32 brightness;
    u32 color;
    u32 max_fade_brightness;
    u32 mode;
    u32 flash_time;
    u32 brightness_index;
};

struct light_ring_i2c_dev
{
    struct pci_dev *pdev;             
    struct i2c_adapter *adapter;      
    struct i2c_client client;         
    struct cdev cdev;                 
    struct class *class;              
    struct device *device;            
    dev_t dev_num;                    
    struct mutex lock;                
    int bus_number;                   
    struct lightring_data *lightring; 
    struct delayed_work delay_work1;
};

static const u8 gamma_to_pwm[101] = {
    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
    0,   0,   0,   0,   0,   0,   0,   0,   0,   1,
    1,   1,   1,   1,   1,   1,   1,   1,   1,   1,
    1,   2,   2,   2,   2,   2,   2,   2,   2,   3,
    3,   3,   3,   3,   4,   4,   4,   4,   5,   5,
    5,   5,   6,   6,   6,   7,   7,   7,   8,   8,
    9,   9,  10,  10,  11,  11,  12,  12,  13,  14,
    14,  15,  16,  17,  17,  18,  19,  20,  21,  22,
    23,  24,  25,  26,  27,  29,  30,  31,  33,  34,
    35,  37,  39,  40,  42,  44,  46,  48,  50,  52,
   100
};
int set_color(unsigned int color);
static struct light_ring_i2c_dev *global_dev = NULL;

static void delay_work_func(struct work_struct *work)
{
    static int flag = 0;
    if(global_dev->lightring->flash_time != 0)
    {
        if(global_dev->lightring->mode == LIGHT_MODE_FLASH_1SEC || \
           global_dev->lightring->mode == LIGHT_MODE_FLASH_2SEC || \
           global_dev->lightring->mode == LIGHT_MODE_FLASH_3SEC)
        {
            if(flag == 0)
            {
                set_color(global_dev->lightring->color);
                flag = 1;
            }
            else
            {
                set_color(0);
                flag = 0;
            }
        }
        else if(global_dev->lightring->mode == LIGHT_MODE_FLASH_SLOW || \
                global_dev->lightring->mode == LIGHT_MODE_FLASH_MEDIUM || \
                global_dev->lightring->mode == LIGHT_MODE_FLASH_FAST)
        {
            if(global_dev->lightring->brightness_index >= 100)
            {
                global_dev->lightring->brightness_index = 0;
            }
            global_dev->lightring->brightness_index++;
            global_dev->lightring->brightness = gamma_to_pwm[global_dev->lightring->brightness_index];
            if(global_dev->lightring->brightness >= 100)
            {
                global_dev->lightring->brightness = 100;
            }
            set_color(global_dev->lightring->color);
        }

	    schedule_delayed_work(&global_dev->delay_work1, msecs_to_jiffies(global_dev->lightring->flash_time));
    }
}

// s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value);
// s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command);

int set_color(unsigned int color)
{
    int i = 0;
    int ret = 0;
    unsigned char red;
    unsigned char green;
    unsigned char blue;

    unsigned char red_pwm_l = 0;
    unsigned char red_pwm_h = 0;
    unsigned char green_pwm_l = 0;
    unsigned char green_pwm_h = 0;
    unsigned char blue_pwm_l = 0;
    unsigned char blue_pwm_h = 0;

    red = 255 - (((color >> 16) & 0xff) * global_dev->lightring->brightness / 100);
    green = 255 - (((color >> 8) & 0xff) * global_dev->lightring->brightness / 100);
    blue = 255 - ((color & 0xff) * global_dev->lightring->brightness / 100);

    red_pwm_l = (red * 4095 / 255) & 0xff;
    red_pwm_h = ((red * 4095 / 255) >> 8) & 0x0f;
    green_pwm_l = (green * 4095 / 255) & 0xff;
    green_pwm_h = ((green * 4095 / 255) >> 8) & 0x0f;
    blue_pwm_l = (blue * 4095 / 255) & 0xff;
    blue_pwm_h = ((blue * 4095 / 255) >> 8) & 0x0f;

    for (i = 0; i < 3; i++)
    {
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x06 + i * 12, 0);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x07 + i * 12, 0);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x08 + i * 12, red_pwm_l);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x09 + i * 12, red_pwm_h);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x0a + i * 12, 0);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x0b + i * 12, 0);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x0c + i * 12, green_pwm_l);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x0d + i * 12, green_pwm_h);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x0e + i * 12, 0);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x0f + i * 12, 0);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x10 + i * 12, blue_pwm_l);
        ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x11 + i * 12, blue_pwm_h);
    }
    if(ret != 0)
    {
        pr_err("set color failed\n");
        return -1;
    }
    return 0;
}

static ssize_t brightness_show(struct kobject *kobj, struct kobj_attribute *attr,
                               char *buf)
{
    return sprintf(buf, "%u\n", global_dev->lightring->brightness);
}

static ssize_t brightness_store(struct kobject *kobj, struct kobj_attribute *attr,
                                const char *buf, size_t count)
{
    u32 val;
    int ret;

    ret = kstrtou32(buf, 10, &val);
    if (ret < 0)
    {
        pr_err("Lightring: brightness format error\n");
        return ret;
    }

    if(val > 100)
    {
        pr_err("Lightring: brightness out of range\n");
        return -1;
    }
    global_dev->lightring->brightness = val;
    set_color(global_dev->lightring->color);

    return count;
}

static struct kobj_attribute brightness_attr =
    __ATTR(brightness, 0644, brightness_show, brightness_store);

/* ==================== color ==================== */
static ssize_t color_show(struct kobject *kobj, struct kobj_attribute *attr,
                          char *buf)
{    const char *mode_str;

    switch (global_dev->lightring->color)
    {
    case COLOR_WHITE:
        mode_str = "white";
        break;
    case COLOR_RED:
        mode_str = "red";
        break;
    case COLOR_GREEN:
        mode_str = "green";
        break;
    case COLOR_BLUE:
        mode_str = "blue";
        break;
    case COLOR_FUCHSIA:
        mode_str = "fuchsia";
        break;
    case COLOR_YELLOW:
        mode_str = "yellow";
        break;
    case COLOR_CYAN:
        mode_str = "cyan";
        break;
    default:
        mode_str = "white";
        break;
    }

    return sprintf(buf, "%s\n", mode_str);
}

static ssize_t color_store(struct kobject *kobj, struct kobj_attribute *attr,
                           const char *buf, size_t count)
{
    u32 val;
    int ret;

    if (strncmp(buf, "White", 5) == 0 || strncmp(buf, "white", 5) == 0)
    {
        val = COLOR_WHITE;
    }
    else if (strncmp(buf, "Red", 3) == 0 || strncmp(buf, "red", 3) == 0)
    {
        val = COLOR_RED;
    }
    else if (strncmp(buf, "Green", 5) == 0 || strncmp(buf, "green", 5) == 0)
    {
        val = COLOR_GREEN;
    }
    else if (strncmp(buf, "Blue", 4) == 0 || strncmp(buf, "blue", 4) == 0)
    {
        val = COLOR_BLUE;
    }
    else if (strncmp(buf, "Fuchsia", 7) == 0 || strncmp(buf, "fuchsia", 7) == 0)
    {
        val = COLOR_FUCHSIA;
    }
    else if (strncmp(buf, "Yellow", 6) == 0 || strncmp(buf, "yellow", 6) == 0)
    {
        val = COLOR_YELLOW;
    }
    else if (strncmp(buf, "Cyan", 4) == 0 || strncmp(buf, "cyan", 4) == 0)
    {
        val = COLOR_CYAN;
    }
    else
    {
        pr_err("Lightring: color format error\n");
        return -1;
    }

    global_dev->lightring->color = val;

    ret = set_color(val);
    if (ret < 0)
    {
        pr_err("Lightring: set color failed\n");
        return ret;
    }

    return count;
}

static struct kobj_attribute color_attr =
    __ATTR(color, 0644, color_show, color_store);

/* ==================== max_fade_brightness ==================== */
static ssize_t max_fade_brightness_show(struct kobject *kobj,
                                        struct kobj_attribute *attr,
                                        char *buf)
{
    return sprintf(buf, "%u\n", global_dev->lightring->max_fade_brightness);
}

static ssize_t max_fade_brightness_store(struct kobject *kobj,
                                         struct kobj_attribute *attr,
                                         const char *buf, size_t count)
{
    u32 val;
    int ret;

    ret = kstrtou32(buf, 10, &val);
    if (ret < 0)
        return ret;

    global_dev->lightring->max_fade_brightness = val;

    return count;
}

static struct kobj_attribute max_fade_brightness_attr =
    __ATTR(max_fade_brightness, 0644, max_fade_brightness_show,
           max_fade_brightness_store);

/* ==================== mode ==================== */
static ssize_t mode_show(struct kobject *kobj, struct kobj_attribute *attr,
                         char *buf)
{
    const char *mode_str;

    switch (global_dev->lightring->mode)
    {
    case LIGHT_MODE_OFF:
        mode_str = "off";
        break;
    case LIGHT_MODE_ON:
        mode_str = "on";
        break;
    case LIGHT_MODE_FLASH_1SEC:
        mode_str = "flash_1sec";
        break;
    case LIGHT_MODE_FLASH_2SEC:
        mode_str = "flash_2sec";
        break;
    case LIGHT_MODE_FLASH_3SEC:
        mode_str = "flash_3sec";
        break;
    case LIGHT_MODE_FLASH_SLOW:
        mode_str = "fade_slow";
        break;
    case LIGHT_MODE_FLASH_MEDIUM:
        mode_str = "fade_medium";
        break;
    case LIGHT_MODE_FLASH_FAST:
        mode_str = "fade_fast";
        break;
    default:
        mode_str = "on";
        break;
    }

    return sprintf(buf, "%s\n", mode_str);
}

static ssize_t mode_store(struct kobject *kobj, struct kobj_attribute *attr,
                          const char *buf, size_t count)
{
    int mode = 0;
    int time = 0;

    

    if (strncmp(buf, "off", 3) == 0)
    {
        mode = LIGHT_MODE_OFF;
        time = 0;
        global_dev->lightring->brightness = 100;
        set_color(0);
    }
    else if (strncmp(buf, "on", 2) == 0)
    {
        mode = LIGHT_MODE_ON;
        time = 0;
        global_dev->lightring->brightness = 100;
        set_color(global_dev->lightring->color);
    }
    else if (strncmp(buf, "flash_1sec", 10) == 0)
    {
        mode = LIGHT_MODE_FLASH_1SEC;
        time = 1000;
        global_dev->lightring->brightness = 100;
    }
    else if (strncmp(buf, "flash_2sec", 10) == 0)
    {
        mode = LIGHT_MODE_FLASH_2SEC;
        time = 2000;
        global_dev->lightring->brightness = 100;
    }
    else if (strncmp(buf, "flash_3sec", 10) == 0)
    {
        mode = LIGHT_MODE_FLASH_3SEC;
        time = 3000;
        global_dev->lightring->brightness = 100;
    }
    else if (strncmp(buf, "fade_slow", 9) == 0)
    {
        mode = LIGHT_MODE_FLASH_SLOW;
        time = 60;
        global_dev->lightring->brightness_index = 0;
    }
    else if (strncmp(buf, "fade_medium", 11) == 0)
    {
        mode = LIGHT_MODE_FLASH_MEDIUM;
        time = 40;
        global_dev->lightring->brightness_index = 0;
    }
    else if (strncmp(buf, "fade_fast", 9) == 0)
    {
        mode = LIGHT_MODE_FLASH_FAST;
        time = 20;
        global_dev->lightring->brightness_index = 0;
    }
    else
    {
        pr_err("Lightring: mode format error\n");
        return -1;
    }

    global_dev->lightring->mode = mode;
    global_dev->lightring->flash_time = time;
    if(time != 0)
    {
        schedule_delayed_work(&global_dev->delay_work1, msecs_to_jiffies(global_dev->lightring->flash_time));
    }
    return count;
}

static struct kobj_attribute mode_attr =
    __ATTR(mode, 0644, mode_show, mode_store);

static struct attribute *lightring_attrs[] = {
    &brightness_attr.attr,
    &color_attr.attr,
    &max_fade_brightness_attr.attr,
    &mode_attr.attr,
    NULL,
};

static struct attribute_group lightring_attr_group = {
    .attrs = lightring_attrs,
};

// static struct kobject *vfiec_kobj;
extern struct kobject *vfiec_kobj;
static struct kobject *lightring_kobj;

static struct i2c_adapter *find_i2c_adapter_by_pci(struct pci_dev *pdev)
{
    struct i2c_adapter *adapter = NULL;
    struct fwnode_handle *fwnode;
    struct device_link *link;
    int i;

    if (!pdev)
        return NULL;

    fwnode = dev_fwnode(&pdev->dev);
    if (!fwnode)
    {
        pr_err("PCI device has no fwnode\n");
        return NULL;
    }


    list_for_each_entry(link, &pdev->dev.links.consumers, s_node)
    {
        if (link->supplier == &pdev->dev)
        {
            if (link->consumer->type &&
                link->consumer->type->name &&
                strcmp(link->consumer->type->name, "i2c_adapter") == 0)
            {
                adapter = i2c_verify_adapter(link->consumer);
                if (adapter)
                    break;
            }
        }
    }

    if (adapter)
    {
        i2c_put_adapter(adapter);               
        adapter = i2c_get_adapter(adapter->nr);
        return adapter;
    }

    for (i = 0; i < 255; i++)
    {
        adapter = i2c_get_adapter(i);
        if (adapter)
        {
            if (adapter->dev.parent == &pdev->dev)
            {
                return adapter;
            }
            i2c_put_adapter(adapter);
        }
    }

    return NULL;
}

static struct pci_dev *init_pci_device(void)
{
    struct pci_dev *pdev;

    pdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0x1f, 4));
    if (!pdev)
    {
        pr_err("Failed to find PCI device 0000:00:1f.4\n");
        return NULL;
    }

    return pdev;
}

int pca9685_all_off(void)
{
    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_ALL_LED_ON_L, 0) < 0)
        return PCA9685_ERR_WRITE;
    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_ALL_LED_ON_H, 0) < 0)
        return PCA9685_ERR_WRITE;
    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_ALL_LED_OFF_L, 0) < 0)
        return PCA9685_ERR_WRITE;
    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_ALL_LED_OFF_H, 0x10) < 0)
        return PCA9685_ERR_WRITE;
    return PCA9685_OK;
}

int pca9685_set_open_drain(bool enable)
{
    uint8_t mode2;
    int ret;
    ret = i2c_smbus_read_byte_data(&global_dev->client, PCA9685_MODE2);
    if (ret < 0)
        return PCA9685_ERR_READ;
    mode2 = ret & 0xff;
    if (enable)
        mode2 &= ~MODE2_OUTDRV;
    else
        mode2 |= MODE2_OUTDRV;
    return i2c_smbus_write_byte_data(&global_dev->client, PCA9685_MODE2, mode2);
}

int pca9685_set_pwm_freq(int freq)
{
    int ret = 0;
    uint8_t prescale, old_mode, new_mode;
    int prescale_val = (PCA9685_OSC_FREQ / (4096 * freq)) - 1;
    prescale = (uint8_t)(prescale_val);
    if (prescale < 3)
        prescale = 3;

    ret = i2c_smbus_read_byte_data(&global_dev->client, PCA9685_MODE1);
    if (ret < 0)
        return PCA9685_ERR_READ;
    old_mode = ret & 0xff;
    new_mode = (old_mode & ~MODE1_RESTART) | MODE1_SLEEP;

    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_MODE1, new_mode) < 0)
        return PCA9685_ERR_WRITE;
    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_PRESCALE, prescale) < 0)
        return PCA9685_ERR_WRITE;
    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_MODE1, old_mode) < 0)
        return PCA9685_ERR_WRITE;

    udelay(5000);
    if (i2c_smbus_write_byte_data(&global_dev->client, PCA9685_MODE1, old_mode | MODE1_RESTART | MODE1_AI) < 0)
    {
        return PCA9685_ERR_WRITE;
    }
    return 0;
}

void init_pca9685(void)
{
    int ret = 0;
    // reset
    ret |= i2c_smbus_write_byte_data(&global_dev->client, 0x00, 0x06);
    udelay(10000);

    ret |= i2c_smbus_write_byte_data(&global_dev->client, PCA9685_MODE2, MODE2_OUTDRV | MODE2_OCH);
    ret |= i2c_smbus_write_byte_data(&global_dev->client, PCA9685_MODE1, MODE1_RESTART | MODE1_AI | MODE1_ALLCALL);

    ret = pca9685_set_pwm_freq(50);
    if (ret != 0)
    {
        pr_err("pca9685_set_pwm_freq failed: %d\n", ret);
    }
    ret = pca9685_all_off();
    if (ret != 0)
    {
        pr_err("pca9685_all_off failed: %d\n", ret);
    }

    ret = pca9685_set_open_drain(true);
    if (ret != 0)
    {
        pr_err("pca9685_set_open_drain failed: %d\n", ret);
    }
}
int light_ring_init(void)
{
    int ret;
    struct light_ring_i2c_dev *dev;


    dev = kzalloc(sizeof(struct light_ring_i2c_dev), GFP_KERNEL);
    if (!dev)
    {
        pr_err("Failed to allocate device structure\n");
        return -ENOMEM;
    }
    global_dev = dev;
    mutex_init(&dev->lock);

    dev->pdev = init_pci_device();
    if (!dev->pdev)
    {
        pr_err("Failed to initialize PCI device\n");
        ret = -ENODEV;
        goto err_free_dev;
    }

    dev->adapter = find_i2c_adapter_by_pci(dev->pdev);
    if (!dev->adapter)
    {
        pr_err("Failed to find I2C adapter\n");
        ret = -ENODEV;
        goto err_put_pci;
    }

    dev->bus_number = dev->adapter->nr;

    if (!i2c_check_functionality(dev->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA |
                                                   I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
    {
        dev_err(&dev->adapter->dev, "Adapter does not support required SMBus features\n");
        return -ENOTSUPP; 
    }

    dev->client.adapter = dev->adapter;      
    dev->client.addr = PCA9685_DEFAULT_ADDR; 
    dev->client.flags = 0;                   

    INIT_DELAYED_WORK(&dev->delay_work1, delay_work_func);

    init_pca9685();

    global_dev->lightring = kzalloc(sizeof(*global_dev->lightring), GFP_KERNEL);
    if (!global_dev->lightring)
    {
        pr_err("Failed to allocate lightring structure\n");
        ret = -ENOMEM;
        goto err_put_pci;
    }

    global_dev->lightring->brightness = 100;
    global_dev->lightring->color = COLOR_WHITE;
    global_dev->lightring->max_fade_brightness = 0;
    global_dev->lightring->mode = LIGHT_MODE_ON; /* static */
    set_color(global_dev->lightring->color);


    lightring_kobj = kobject_create_and_add("lightring", vfiec_kobj);
    if (!lightring_kobj)
    {
        ret = -ENOMEM;
        goto err_free;
    }


    ret = sysfs_create_group(lightring_kobj, &lightring_attr_group);
    if (ret)
    {
        pr_err("Failed to create sysfs group: %d\n", ret);
        goto err_lightring;
    }

    return 0;
err_lightring:
    kobject_put(lightring_kobj);
// err_vfiec:
//     kobject_put(vfiec_kobj);
err_free:
    kfree(global_dev->lightring);
err_put_pci:
    pci_dev_put(dev->pdev);
err_free_dev:
    kfree(dev);
    global_dev = NULL;
    return ret;
}

void light_ring_exit(void)
{
    struct light_ring_i2c_dev *dev = global_dev;
    global_dev->lightring->flash_time = 0;
    cancel_delayed_work_sync(&global_dev->delay_work1);
    sysfs_remove_group(lightring_kobj, &lightring_attr_group);
    kobject_put(lightring_kobj);
    // kobject_put(vfiec_kobj);
    kfree(global_dev->lightring);
    if (dev->adapter)
        i2c_put_adapter(dev->adapter);

    if (dev->pdev)
        pci_dev_put(dev->pdev);

    kfree(dev);
    global_dev = NULL;
}