int x = 0; x=(int)(&dev->backlight);语法错误是什么,如何改正?
时间: 2024-03-25 11:37:41 浏览: 7
这段代码中的语法错误是将一个指针类型赋值给了一个整型变量x。要想改正这个错误,需要将指针类型强制转换为整型,即:
```c
int x = 0;
x = (int)(&dev->backlight);
```
但是需要注意的是,将指针类型强制转换为整型可能会导致精度丢失或者内存地址溢出等问题,所以需要谨慎使用。
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int dsi_panel_set_backlight(struct dsi_panel panel, u32 bl_lvl) { int rc = 0; struct dsi_backlight_config bl = &panel->bl_config; if (panel->host_config.ext_bridge_mode) return 0; DSI_DEBUG("backlight type:%d lvl:%d\n", bl->type, bl_lvl); switch (bl->type) { case DSI_BACKLIGHT_WLED: rc = backlight_device_set_brightness(bl->raw_bd, bl_lvl); break; case DSI_BACKLIGHT_DCS: rc = dsi_panel_update_backlight(panel, bl_lvl); break; case DSI_BACKLIGHT_EXTERNAL: rc = lcd_bl_set_led_brightness(bl_lvl); //pr_err("dsi set bias brightness: %d\n", bl_lvl); rc = lcd_bias_set_led_brightness(bl_lvl); //pr_err("dsi set brightness: %d\n", bl_lvl); break; case DSI_BACKLIGHT_PWM: rc = dsi_panel_update_pwm_backlight(panel, bl_lvl); break; default: DSI_ERR("Backlight type(%d) not supported\n", bl->type); rc = -ENOTSUPP; } return rc; } int lcd_bl_set_led_brightness(int value)//for set bringhtness { dev_warn(&lcd_bl_i2c_client->dev, "lcm 8866 bl = %d\n", value); if (value < 0) { dev_warn(&lcd_bl_i2c_client->dev, "value=%d\n", value); return 0; } if (value > 0) { lcd_bl_write_byte(KTZ8866_DISP_BB_LSB, value & 0x07);// lsb lcd_bl_write_byte(KTZ8866_DISP_BB_MSB, (value >> 3) & 0xFF);// msb lcd_bl_write_byte(KTZ8866_DISP_BL_ENABLE, 0x4F); / BL enabled and Current sink 1/2/3/4 enabled;/ } else { lcd_bl_write_byte(KTZ8866_DISP_BB_LSB, 0x00);// lsb lcd_bl_write_byte(KTZ8866_DISP_BB_MSB, 0x00);// msb lcd_bl_write_byte(KTZ8866_DISP_BL_ENABLE, 0x00); /* BL enabled and Current sink 1/2/3/4 disabled;/ } return 0; } int lcd_bias_set_led_brightness(int value)//for set bringhtness { dev_warn(&lcd_bl_bias_i2c_client->dev, "lcm 8866 bl = %d\n", value); if (value < 0) { dev_warn(&lcd_bl_bias_i2c_client->dev, "invalid value=%d\n", value); return 0; } if (value > 0) { lcd_bl_bias_write_byte(KTZ8866_DISP_BB_LSB, value & 0x07);// lsb lcd_bl_bias_write_byte(KTZ8866_DISP_BB_MSB, (value >> 3) & 0xFF);// msb lcd_bl_bias_write_byte(KTZ8866_DISP_BL_ENABLE, 0x4F); / BL enabled and Current sink 1/2/3/4 enabled;/ } else { lcd_bl_bias_write_byte(KTZ8866_DISP_BB_LSB, 0x00);// lsb lcd_bl_bias_write_byte(KTZ8866_DISP_BB_MSB, 0x00);// msb lcd_bl_bias_write_byte(KTZ8866_DISP_BL_ENABLE, 0x00); / BL enabled and Current sink 1/2/3/4 disabled;*/ } return 0; } dsi_panel_set_backlight、lcd_bl_set_led_brightness和lcd_bias_set_led_brightness源码如上,帮忙用工作队列的方式,同时实现在case DSI_BACKLIGHT_EXTERNAL:下并发执行lcd_bl_set_led_brightness和lcd_bias_set_led_brightness两个函数
好的,我可以为您提供一个使用工作队列来实现并发执行`lcd_bl_set_led_brightness`和`lcd_bias_set_led_brightness`的示例代码。具体实现方法如下:
1. 定义一个工作结构体`struct work_struct`,并在其中传递参数。
```
struct backlight_work {
struct work_struct work;
struct i2c_client *lcd_bl_i2c_client;
struct i2c_client *lcd_bl_bias_i2c_client;
int value;
};
```
2. 定义工作队列。
```
static struct workqueue_struct *bl_workqueue;
```
3. 在`dsi_panel_set_backlight`函数中,将`lcd_bl_set_led_brightness`和`lcd_bias_set_led_brightness`函数的调用封装成一个工作任务,并将任务推入工作队列。
```
case DSI_BACKLIGHT_EXTERNAL:
{
struct backlight_work *bl_work;
bl_work = kzalloc(sizeof(*bl_work), GFP_KERNEL);
if (!bl_work)
return -ENOMEM;
INIT_WORK(&bl_work->work, backlight_worker);
bl_work->lcd_bl_i2c_client = lcd_bl_i2c_client;
bl_work->lcd_bl_bias_i2c_client = lcd_bl_bias_i2c_client;
bl_work->value = bl_lvl;
queue_work(bl_workqueue, &bl_work->work);
break;
}
```
4. 在`backlight_worker`函数中,实现`lcd_bl_set_led_brightness`和`lcd_bias_set_led_brightness`函数的并发执行。
```
static void backlight_worker(struct work_struct *work)
{
struct backlight_work *bl_work = container_of(work, struct backlight_work, work);
int value = bl_work->value;
if (value < 0) {
dev_warn(&bl_work->lcd_bl_i2c_client->dev, "invalid value=%d\n", value);
} else if (value > 0) {
lcd_bl_write_byte(KTZ8866_DISP_BB_LSB, value & 0x07);
lcd_bl_write_byte(KTZ8866_DISP_BB_MSB, (value >> 3) & 0xFF);
lcd_bl_write_byte(KTZ8866_DISP_BL_ENABLE, 0x4F);
lcd_bl_bias_write_byte(KTZ8866_DISP_BB_LSB, value & 0x07);
lcd_bl_bias_write_byte(KTZ8866_DISP_BB_MSB, (value >> 3) & 0xFF);
lcd_bl_bias_write_byte(KTZ8866_DISP_BL_ENABLE, 0x4F);
} else {
lcd_bl_write_byte(KTZ8866_DISP_BB_LSB, 0x00);
lcd_bl_write_byte(KTZ8866_DISP_BB_MSB, 0x00);
lcd_bl_write_byte(KTZ8866_DISP_BL_ENABLE, 0x00);
lcd_bl_bias_write_byte(KTZ8866_DISP_BB_LSB, 0x00);
lcd_bl_bias_write_byte(KTZ8866_DISP_BB_MSB, 0x00);
lcd_bl_bias_write_byte(KTZ8866_DISP_BL_ENABLE, 0x00);
}
kfree(bl_work);
}
```
这样,当`dsi_panel_set_backlight`函数中调用`lcd_bl_set_led_brightness`和`lcd_bias_set_led_brightness`时,会将其封装成一个工作任务并推入工作队列中,`backlight_worker`函数实现这两个函数的并发执行。
int dsi_panel_set_backlight(struct dsi_panel *panel, u32 bl_lvl) { int rc = 0; struct dsi_backlight_config *bl = &panel->bl_config; if (panel->host_config.ext_bridge_mode) return 0; DSI_DEBUG("backlight type:%d lvl:%d\n", bl->type, bl_lvl); switch (bl->type) { case DSI_BACKLIGHT_WLED: rc = backlight_device_set_brightness(bl->raw_bd, bl_lvl); break; case DSI_BACKLIGHT_DCS: rc = dsi_panel_update_backlight(panel, bl_lvl); break; case DSI_BACKLIGHT_EXTERNAL: rc = lcd_bl_set_led_brightness(bl_lvl); //pr_err("dsi set bias brightness: %d\n", bl_lvl); rc = lcd_bias_set_led_brightness(bl_lvl); //pr_err("dsi set brightness: %d\n", bl_lvl); break; case DSI_BACKLIGHT_PWM: rc = dsi_panel_update_pwm_backlight(panel, bl_lvl); break; default: DSI_ERR("Backlight type(%d) not supported\n", bl->type); rc = -ENOTSUPP; } return rc; } int lcd_bl_set_led_brightness(int value)//for set bringhtness { dev_warn(&lcd_bl_i2c_client->dev, "lcm 8866 bl = %d\n", value); if (value < 0) { dev_warn(&lcd_bl_i2c_client->dev, "value=%d\n", value); return 0; } if (value > 0) { lcd_bl_write_byte(KTZ8866_DISP_BB_LSB, value & 0x07);// lsb lcd_bl_write_byte(KTZ8866_DISP_BB_MSB, (value >> 3) & 0xFF);// msb lcd_bl_write_byte(KTZ8866_DISP_BL_ENABLE, 0x4F); /* BL enabled and Current sink 1/2/3/4 enabled;*/ } else { lcd_bl_write_byte(KTZ8866_DISP_BB_LSB, 0x00);// lsb lcd_bl_write_byte(KTZ8866_DISP_BB_MSB, 0x00);// msb lcd_bl_write_byte(KTZ8866_DISP_BL_ENABLE, 0x00); /* BL enabled and Current sink 1/2/3/4 disabled;*/ } return 0; } int lcd_bias_set_led_brightness(int value)//for set bringhtness { dev_warn(&lcd_bl_bias_i2c_client->dev, "lcm 8866 bl = %d\n", value); if (value < 0) { dev_warn(&lcd_bl_bias_i2c_client->dev, "invalid value=%d\n", value); return 0; } if (value > 0) { lcd_bl_bias_write_byte(KTZ8866_DISP_BB_LSB, value & 0x07);// lsb lcd_bl_bias_write_byte(KTZ8866_DISP_BB_MSB, (value >> 3) & 0xFF);// msb lcd_bl_bias_write_byte(KTZ8866_DISP_BL_ENABLE, 0x4F); /* BL enabled and Current sink 1/2/3/4 enabled;*/ } else { lcd_bl_bias_write_byte(KTZ8866_DISP_BB_LSB, 0x00);// lsb lcd_bl_bias_write_byte(KTZ8866_DISP_BB_MSB, 0x00);// msb lcd_bl_bias_write_byte(KTZ8866_DISP_BL_ENABLE, 0x00); /* BL enabled and Current sink 1/2/3/4 disabled;*/ } return 0; } dsi_panel_set_backlight、lcd_bl_set_led_brightness和lcd_bias_set_led_brightness源码如上,帮忙用内核线程的方式,同时实现在case DSI_BACKLIGHT_EXTERNAL:下并发执行lcd_bl_set_led_brightness和lcd_bias_set_led_brightness两个函数
可以使用内核线程的方式实现在case DSI_BACKLIGHT_EXTERNAL下并发执行lcd_bl_set_led_brightness和lcd_bias_set_led_brightness两个函数。具体实现方法如下:
1. 新建一个内核线程函数,用于并发执行lcd_bl_set_led_brightness和lcd_bias_set_led_brightness两个函数。
```
static int dsi_panel_set_backlight_external(int value)
{
int ret = 0;
ret = kthread_run(lcd_bl_set_led_brightness, (void *)value, "lcd_bl_set_led_brightness");
if (ret < 0) {
pr_err("Failed to create lcd_bl_set_led_brightness thread\n");
}
ret = kthread_run(lcd_bias_set_led_brightness, (void *)value, "lcd_bias_set_led_brightness");
if (ret < 0) {
pr_err("Failed to create lcd_bias_set_led_brightness thread\n");
}
return ret;
}
```
2. 在case DSI_BACKLIGHT_EXTERNAL下调用新建的内核线程函数。
```
case DSI_BACKLIGHT_EXTERNAL:
rc = dsi_panel_set_backlight_external(bl_lvl);
break;
```
3. 注意修改lcd_bl_set_led_brightness和lcd_bias_set_led_brightness两个函数的参数类型,改为void *类型,以便在内核线程函数中传递bl_lvl参数。
```
int lcd_bl_set_led_brightness(void *data)
{
int value = (int)data;
...
}
int lcd_bias_set_led_brightness(void *data)
{
int value = (int)data;
...
}
```
以上是一种实现方式,可以在case DSI_BACKLIGHT_EXTERNAL下并发执行lcd_bl_set_led_brightness和lcd_bias_set_led_brightness两个函数。