CONFIG MSB是什么意思
时间: 2024-08-05 21:00:57 浏览: 61
CONFIG MSB通常是指配置模式标志位(Master Status Bit),它在某些嵌入式系统、微控制器或者I2C通信协议中使用。MSB代表Master(主设备)的状态位,用于表示当前I2C总线上的主设备是否准备好接收数据或者发送数据。当主设备处于从设备可以应答的状态时,该位通常会设置为高电平;相反,如果主设备正在进行操作或者不可用,则MSB会被拉低。通过读取这个位,其他设备能够知道何时能安全地开始传输数据。
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ESP32 i2s_config
ESP32的i2s_config是用于配置ESP32的I2S(Inter-IC Sound)接口的结构体。I2S是一种用于音频数据传输的串行接口协议,常用于音频设备之间的数字音频传输。
i2s_config结构体包含了一系列参数,用于配置I2S接口的工作模式、时钟频率、数据格式等。以下是i2s_config结构体的一些重要参数:
1. mode:指定I2S接口的工作模式,可以是主模式(I2S_MODE_MASTER)或从模式(I2S_MODE_SLAVE)。
2. sample_rate:指定音频数据的采样率,单位为Hz。
3. bits_per_sample:指定每个采样点的位数,常见的有16位和32位。
4. channel_format:指定音频数据的通道格式,可以是单声道(I2S_CHANNEL_MONO)或立体声(I2S_CHANNEL_STEREO)。
5. communication_format:指定I2S接口的数据格式,可以是左对齐(I2S_COMM_FORMAT_I2S)、右对齐(I2S_COMM_FORMAT_I2S_MSB)、左右对齐(I2S_COMM_FORMAT_I2S_LSB)等。
6. intr_alloc_flags:指定中断分配标志,用于指定中断服务程序的分配方式。
通过配置i2s_config结构体中的参数,可以实现对ESP32的I2S接口进行灵活的配置,以满足不同的音频传输需求。
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。