Pin驅(qū)動(dòng)框架

以NXP MCXA153為例

PIN設(shè)備驅(qū)動(dòng)層

單純的提供接口給應(yīng)用層用，其中PIN設(shè)備驅(qū)動(dòng)框架接口包含rt_pin_read等，具體在pin.c 文件中查看

pin.c是提供應(yīng)用接口

drv_gpio.c是具體實(shí)現(xiàn)

實(shí)現(xiàn)操作方法原理

struct rt_pin_ops{ void (*pin_mode)(struct rt_device *device, rt_base_t pin, rt_uint8_t mode); void (*pin_write)(struct rt_device *device, rt_base_t pin, rt_uint8_t value); rt_ssize_t (*pin_read)(struct rt_device *device, rt_base_t pin); rt_err_t (*pin_attach_irq)(struct rt_device *device, rt_base_t pin, rt_uint8_t mode, void (*hdr)(void *args), void *args); rt_err_t (*pin_detach_irq)(struct rt_device *device, rt_base_t pin); rt_err_t (*pin_irq_enable)(struct rt_device *device, rt_base_t pin, rt_uint8_t enabled); rt_base_t (*pin_get)(const char *name);#ifdef RT_USING_DM rt_err_t (*pin_irq_mode)(struct rt_device *device, rt_base_t pin, rt_uint8_t mode); rt_ssize_t (*pin_parse)(struct rt_device *device, struct rt_ofw_cell_args *args, rt_uint32_t *flags);#endif#ifdef RT_USING_PINCTRL rt_err_t (*pin_ctrl_confs_apply)(struct rt_device *device, void *fw_conf_np);#endif /* RT_USING_PINCTRL */};

rt_pin_ops 成員介紹

pin_mode

引腳初始化

pin_write

引腳寫

pin_read

引腳讀

pin_attach_irq

中斷操作 為某個(gè)引腳綁定一個(gè)中斷回調(diào)函數(shù)，使能中斷，當(dāng)中斷來(lái)時(shí)調(diào)用該函數(shù)

pin_detach_irq

中斷操作 脫離某個(gè)引腳的中斷回調(diào)函數(shù)

pin_irq_enable

中斷操作 開(kāi)啟或關(guān)閉中斷

pin_get

獲取某個(gè)pin腳編號(hào)

pin_irq_mode

pin_parse

pin_ctrl_confs_apply

引腳編號(hào)

#define GET_GPIO_PORT(x) ((x) / 32)#defineGET_GPIO_PIN(x)((x)%32)

rt_pin_ops 賦值

rt_hw_pin_init(){ int ret = RT_EOK; mcx_pin_ops.pin_mode = mcx_pin_mode; mcx_pin_ops.pin_read = mcx_pin_read; mcx_pin_ops.pin_write = mcx_pin_write; mcx_pin_ops.pin_attach_irq = mcx_pin_attach_irq; mcx_pin_ops.pin_detach_irq = mcx_pin_detach_irq; mcx_pin_ops.pin_irq_enable = mcx_pin_irq_enable; mcx_pin_ops.pin_get = RT_NULL, ret = rt_device_pin_register("pin", &mcx_pin_ops, RT_NULL);// return ret;}INIT_BOARD_EXPORT(rt_hw_pin_init);

注意：這里的操作很奇怪INIT_BOARD_EXPORT ，根據(jù)老師的講解是在預(yù)編譯的時(shí)候就處理了，具體后面再學(xué)習(xí)。。。

drv_pin.c 的 rt_hw_pin_init 將底層驅(qū)動(dòng)和驅(qū)動(dòng)框架進(jìn)行鏈接起來(lái)，此文件實(shí)現(xiàn)gpio的初始化

添加Pin驅(qū)動(dòng)代碼流程

編寫drv_pin.c文件

實(shí)現(xiàn) rt_pin_ops 的各種操作接口函數(shù)

然后利用 rt_hw_pin_init 進(jìn)行鏈接驅(qū)動(dòng)層

實(shí)際上就是指針的賦值

實(shí)驗(yàn)代碼

rt_pin_mode(LED_PIN, PIN_MODE_OUTPUT); /* Set GPIO as Output */rt_pin_mode(KEY_BAND, PIN_MODE_INPUT);rt_kprintf("MCXA153 HelloWorld\r\n");while (1){ rt_thread_mdelay(1000); if(rt_pin_read(KEY_BAND)) rt_pin_write(LED_PIN, PIN_HIGH); /* Set GPIO output 1 */ else rt_pin_write(LED_PIN, PIN_LOW); /* Set GPIO output 0 */ #if 0 rt_pin_write(LED_PIN, PIN_HIGH); /* Set GPIO output 1 */ rt_thread_mdelay(500); /* Delay 500mS */ rt_pin_write(LED_PIN, PIN_LOW); /* Set GPIO output 0 */ rt_thread_mdelay(500); /* Delay 500mS */ #endif}

注意：這里延遲1s,目的是為了有msh 功能

總結(jié)

學(xué)習(xí)了PIN設(shè)備驅(qū)動(dòng)框架的添加