使用libusb异步函数读取USB鼠标、上机实验

IMX6ULL/doc_pic/12_USB/07_使用libusb读取鼠标数据.md

@@ -208,7 +208,149 @@ USB规范里为每个按键定义了16位的按键值，注意：它是16位的
 ### 2.1 编写源码
 
 ```c
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
+#include <libusb-1.0/libusb.h>
+
+int main(int argc, char **argv)
+{
+    int err;
+    libusb_device *dev, **devs;
+    int num_devices;
+    int endpoint;
+    int interface_num;
+    int found = 0;
+    int transferred;
+    int count = 0;
+    unsigned char buffer[16];
+    struct libusb_config_descriptor *config_desc;
+    struct libusb_device_handle *dev_handle = NULL;
+    
+    /* libusb_init */
+
+    err = libusb_init(NULL);
+    if (err < 0) {
+        fprintf(stderr, "failed to initialise libusb %d - %s\n", err, libusb_strerror(err));
+        exit(1);
+    }
+
+    /* get device list */
+    if ((num_devices = libusb_get_device_list(NULL, &devs)) < 0) {
+        fprintf(stderr, "libusb_get_device_list() failed\n");
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "libusb_get_device_list() ok\n");
+
+    /* for each device, get config descriptor */
+    for (int i = 0; i < num_devices; i++) {
+        dev = devs[i];
+
+        /* parse interface descriptor, find usb mouse */        
+        err = libusb_get_config_descriptor(dev, 0, &config_desc);
+        if (err) {
+            fprintf(stderr, "could not get configuration descriptor\n");
+            continue;
+        }
+        fprintf(stdout, "libusb_get_config_descriptor() ok\n");
+
+        for (int interface = 0; interface < config_desc->bNumInterfaces; interface++) {
+            const struct libusb_interface_descriptor *intf_desc = &config_desc->interface[interface].altsetting[0];
+            interface_num = intf_desc->bInterfaceNumber;
+
+            if (intf_desc->bInterfaceClass != 3 || intf_desc->bInterfaceProtocol != 2)
+                continue;
+            else
+            {
+                /* 找到了USB鼠标 */
+                fprintf(stdout, "find usb mouse ok\n");
+                for (int ep = 0; ep < intf_desc->bNumEndpoints; ep++)
+                {
+                    if ((intf_desc->endpoint[ep].bmAttributes & 3) == LIBUSB_TRANSFER_TYPE_INTERRUPT ||
+                            (intf_desc->endpoint[ep].bEndpointAddress & 0x80) == LIBUSB_ENDPOINT_IN) {
+                        /* 找到了输入的中断端点 */
+                        fprintf(stdout, "find in int endpoint\n");
+                        endpoint = intf_desc->endpoint[ep].bEndpointAddress;
+                        found = 1;
+                        break;
+                    }
+                    
+                }
+            }
+
+            if (found)
+                break;
+        }
+
+        libusb_free_config_descriptor(config_desc);
+        
+        if (found)
+            break;        
+    }
+
+    if (!found)
+    {
+        /* free device list */
+        libusb_free_device_list(devs, 1);
+        libusb_exit(NULL);
+        exit(1);
+    }
+
+    if (found)
+    {
+        /* libusb_open */
+        err = libusb_open(dev, &dev_handle);
+        if (err)
+        {
+            fprintf(stderr, "failed to open usb mouse\n");
+            exit(1);
+        }
+        fprintf(stdout, "libusb_open ok\n");
+    }
+
+    /* free device list */
+    libusb_free_device_list(devs, 1);
+
+    /* claim interface */
+    libusb_set_auto_detach_kernel_driver(dev_handle, 1);  
+    err = libusb_claim_interface(dev_handle, interface_num);
+    if (err)
+    {
+        fprintf(stderr, "failed to libusb_claim_interface\n");
+        exit(1);
+    }
+    fprintf(stdout, "libusb_claim_interface ok\n");
+
+    /* libusb_interrupt_transfer */
+    while (1)
+    {
+        err = libusb_interrupt_transfer(dev_handle, endpoint, buffer, 16, &transferred, 5000);
+        if (!err) {
+            /* parser data */
+            printf("%04d datas: ", count++);
+            for (int i = 0; i < transferred; i++)
+            {
+                printf("%02x ", buffer[i]);
+            }
+            printf("\n");
+        } else if (err == LIBUSB_ERROR_TIMEOUT){
+            fprintf(stderr, "libusb_interrupt_transfer timout\n");
+        } else {
+            fprintf(stderr, "libusb_interrupt_transfer err : %d\n", err);
+            //exit(1);
+        }
+        
+    }
+
+    /* libusb_close */
+    libusb_release_interface(dev_handle, interface_num);
+    libusb_close(dev_handle);
+    libusb_exit(NULL);
+}
 ```
 
 
@@ -230,7 +372,7 @@ gcc -o readmouse readmouse.c -lusb-1.0
 
 
 
-#### 2.2.2 在开发板上实验
+#### 2.2.2 在IMX6ULL开发板上实验
 
 
 
@@ -269,13 +411,295 @@ gcc -o readmouse readmouse.c -lusb-1.0
 * 交叉编译app
 
   ```shell
-  arm-buildroot-linux-gnueabihf-gcc -o readmouse readmouse.c -lusb-1.0
+  arm-buildroot-linux-gnueabihf-gcc -o  readmouse.c -lusb-1.0
+  ```
+
+
+* 在开发板上插入USB鼠标，执行命令
+
+  ```shell
+  ./readmouse
   ```
 
   
 
 
 
+#### 2.2.3 在STM32MP157开发板上实验
+
+* STM32MP157的工具链里已经含有libusb，所以无需交叉编译、安装libusb
+
+* 交叉编译app
+
+  ```shell
+  arm-buildroot-linux-gnueabihf-gcc -o readmouse readmouse.c -lusb-1.0
+  ```
+
+* 在开发板上插入USB鼠标，执行命令
+
+  ```shell
+  ./readmouse
+  ```
+
+  
+
+
+
+## 3. 使用异步接口读取鼠标数据
+
+源码在GIT仓库如下位置：
+
+![image-20220929092859668](pic/61_libusb_async_usbmouse_src.png)
+
+### 3.1 编写源码
+
+```c
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libusb-1.0/libusb.h>
+
+struct usb_mouse {
+    struct libusb_device_handle *handle;
+    int interface;
+    int endpoint;
+    unsigned char buf[16];
+    int transferred;
+    struct libusb_transfer *transfer;
+    struct usb_mouse *next;
+};
+
+static struct usb_mouse *usb_mouse_list;
+
+
+void free_usb_mouses(struct usb_mouse *usb_mouse_list)
+{
+    struct usb_mouse *pnext;
+    while (usb_mouse_list)
+    {
+        pnext = usb_mouse_list->next;
+        free(usb_mouse_list);
+        usb_mouse_list = pnext;
+    }
+}
+
+
+/*  */
+int get_usb_mouses(libusb_device **devs, int num_devices, struct usb_mouse **usb_mouse_list)
+{
+    int err;
+    libusb_device *dev;
+    int endpoint;
+    int interface_num;
+    struct libusb_config_descriptor *config_desc;
+    struct libusb_device_handle *dev_handle = NULL;
+    struct usb_mouse *pmouse;
+    struct usb_mouse *list = NULL;
+    int mouse_cnt = 0;
+
+    /* for each device, get config descriptor */
+    for (int i = 0; i < num_devices; i++) {
+        dev = devs[i];
+
+        /* parse interface descriptor, find usb mouse */        
+        err = libusb_get_config_descriptor(dev, 0, &config_desc);
+        if (err) {
+            fprintf(stderr, "could not get configuration descriptor\n");
+            continue;
+        }
+        fprintf(stdout, "libusb_get_config_descriptor() ok\n");
+
+        for (int interface = 0; interface < config_desc->bNumInterfaces; interface++) {
+            const struct libusb_interface_descriptor *intf_desc = &config_desc->interface[interface].altsetting[0];
+            interface_num = intf_desc->bInterfaceNumber;
+
+            if (intf_desc->bInterfaceClass != 3 || intf_desc->bInterfaceProtocol != 2)
+                continue;
+            else
+            {
+                /* 找到了USB鼠标 */
+                fprintf(stdout, "find usb mouse ok\n");
+                for (int ep = 0; ep < intf_desc->bNumEndpoints; ep++)
+                {
+                    if ((intf_desc->endpoint[ep].bmAttributes & 3) == LIBUSB_TRANSFER_TYPE_INTERRUPT ||
+                            (intf_desc->endpoint[ep].bEndpointAddress & 0x80) == LIBUSB_ENDPOINT_IN) {
+                        /* 找到了输入的中断端点 */
+                        fprintf(stdout, "find in int endpoint\n");
+                        endpoint = intf_desc->endpoint[ep].bEndpointAddress;
+
+                        /* libusb_open */
+                        err = libusb_open(dev, &dev_handle);
+                        if (err)
+                        {
+                            fprintf(stderr, "failed to open usb mouse\n");
+                            return -1;
+                        }
+                        fprintf(stdout, "libusb_open ok\n");
+
+                        /* 记录下来: 放入链表 */
+                        pmouse = malloc(sizeof(struct usb_mouse));
+                        if (!pmouse)
+                        {
+                            fprintf(stderr, "can not malloc\n");
+                            return -1;
+                        }
+                        pmouse->endpoint  = endpoint;
+                        pmouse->interface = interface_num;
+                        pmouse->handle    = dev_handle;
+                        pmouse->next      = NULL;
+
+                        if (!list)
+                            list = pmouse;
+                        else
+                        {
+                            pmouse->next = list;
+                            list = pmouse;
+                        }
+                        mouse_cnt++;
+                        break;
+                    }
+                    
+                }
+            }
+
+        }
+
+        libusb_free_config_descriptor(config_desc);
+    }
+
+    *usb_mouse_list = list;
+    return mouse_cnt;
+}
+
+
+static void mouse_irq(struct libusb_transfer *transfer)
+{
+    static int count = 0;
+    if (transfer->status == LIBUSB_TRANSFER_COMPLETED)
+    {
+        /* parser data */
+        printf("%04d datas: ", count++);
+        for (int i = 0; i < transfer->actual_length; i++)
+        {
+            printf("%02x ", transfer->buffer[i]);
+        }
+        printf("\n");
+        
+    }
+
+    if (libusb_submit_transfer(transfer) < 0)
+    {
+        fprintf(stderr, "libusb_submit_transfer err\n");
+    }
+}
+
+int main(int argc, char **argv)
+{
+    int err;
+    libusb_device **devs;
+    int num_devices, num_mouse;
+    struct usb_mouse *pmouse;
+    
+    /* libusb_init */
+
+    err = libusb_init(NULL);
+    if (err < 0) {
+        fprintf(stderr, "failed to initialise libusb %d - %s\n", err, libusb_strerror(err));
+        exit(1);
+    }
+
+    /* get device list */
+    if ((num_devices = libusb_get_device_list(NULL, &devs)) < 0) {
+        fprintf(stderr, "libusb_get_device_list() failed\n");
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "libusb_get_device_list() ok\n");
+
+    /* get usb mouse */
+    num_mouse = get_usb_mouses(devs, num_devices, &usb_mouse_list);
+
+    if (num_mouse <= 0)
+    {
+        /* free device list */
+        libusb_free_device_list(devs, 1);
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "get %d mouses\n", num_mouse);
+
+    /* free device list */
+    libusb_free_device_list(devs, 1);
+
+    /* claim interface */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_set_auto_detach_kernel_driver(pmouse->handle, 1);  
+        err = libusb_claim_interface(pmouse->handle, pmouse->interface);
+        if (err)
+        {
+            fprintf(stderr, "failed to libusb_claim_interface\n");
+            exit(1);
+        }
+        pmouse = pmouse->next;
+    }
+    fprintf(stdout, "libusb_claim_interface ok\n");
+
+    /* for each mouse, alloc transfer, fill transfer, submit transfer */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        /* alloc transfer */
+        pmouse->transfer = libusb_alloc_transfer(0);
+
+        /* fill transfer */
+        libusb_fill_interrupt_transfer(pmouse->transfer, pmouse->handle, pmouse->endpoint, pmouse->buf,
+            sizeof(pmouse->buf), mouse_irq, pmouse, 0);
+
+        /* submit transfer */
+        libusb_submit_transfer(pmouse->transfer);
+        
+        pmouse = pmouse->next;
+    }
+
+    /* handle events */
+    while (1) {
+        struct timeval tv = { 5, 0 };
+        int r;
+
+        r = libusb_handle_events_timeout(NULL, &tv);
+        if (r < 0) {
+            fprintf(stderr, "libusb_handle_events_timeout err\n");
+            break;
+        }
+    }
+    
+
+    /* libusb_close */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_release_interface(pmouse->handle, pmouse->interface);
+        libusb_close(pmouse->handle);        
+        pmouse = pmouse->next;
+    }
+
+    free_usb_mouses(usb_mouse_list);
+    
+    libusb_exit(NULL);
+}
+```
+
+
+
+
+
+### 3.2 在开发板上实验
+
 
 
 

IMX6ULL/source/12_USB/03_libusb_mouse_async/readmouse.c

@@ -0,0 +1,240 @@
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libusb-1.0/libusb.h>
+
+struct usb_mouse {
+    struct libusb_device_handle *handle;
+    int interface;
+    int endpoint;
+    unsigned char buf[16];
+    int transferred;
+    struct libusb_transfer *transfer;
+    struct usb_mouse *next;
+};
+
+static struct usb_mouse *usb_mouse_list;
+
+
+void free_usb_mouses(struct usb_mouse *usb_mouse_list)
+{
+    struct usb_mouse *pnext;
+    while (usb_mouse_list)
+    {
+        pnext = usb_mouse_list->next;
+        free(usb_mouse_list);
+        usb_mouse_list = pnext;
+    }
+}
+
+
+/*  */
+int get_usb_mouses(libusb_device **devs, int num_devices, struct usb_mouse **usb_mouse_list)
+{
+    int err;
+    libusb_device *dev;
+    int endpoint;
+    int interface_num;
+    struct libusb_config_descriptor *config_desc;
+    struct libusb_device_handle *dev_handle = NULL;
+    struct usb_mouse *pmouse;
+    struct usb_mouse *list = NULL;
+    int mouse_cnt = 0;
+
+    /* for each device, get config descriptor */
+    for (int i = 0; i < num_devices; i++) {
+        dev = devs[i];
+
+        /* parse interface descriptor, find usb mouse */        
+        err = libusb_get_config_descriptor(dev, 0, &config_desc);
+        if (err) {
+            fprintf(stderr, "could not get configuration descriptor\n");
+            continue;
+        }
+        fprintf(stdout, "libusb_get_config_descriptor() ok\n");
+
+        for (int interface = 0; interface < config_desc->bNumInterfaces; interface++) {
+            const struct libusb_interface_descriptor *intf_desc = &config_desc->interface[interface].altsetting[0];
+            interface_num = intf_desc->bInterfaceNumber;
+
+            if (intf_desc->bInterfaceClass != 3 || intf_desc->bInterfaceProtocol != 2)
+                continue;
+            else
+            
+{
+                /* 找到了USB鼠标 */
+                fprintf(stdout, "find usb mouse ok\n");
+                for (int ep = 0; ep < intf_desc->bNumEndpoints; ep++)
+                {
+                    if ((intf_desc->endpoint[ep].bmAttributes & 3) == LIBUSB_TRANSFER_TYPE_INTERRUPT ||
+                            (intf_desc->endpoint[ep].bEndpointAddress & 0x80) == LIBUSB_ENDPOINT_IN) {
+                        /* 找到了输入的中断端点 */
+                        fprintf(stdout, "find in int endpoint\n");
+                        endpoint = intf_desc->endpoint[ep].bEndpointAddress;
+
+                        /* libusb_open */
+                        err = libusb_open(dev, &dev_handle);
+                        if (err)
+                        {
+                            fprintf(stderr, "failed to open usb mouse\n");
+                            return -1;
+                        }
+                        fprintf(stdout, "libusb_open ok\n");
+
+                        /* 记录下来: 放入链表 */
+                        pmouse = malloc(sizeof(struct usb_mouse));
+                        if (!pmouse)
+                        {
+                            fprintf(stderr, "can not malloc\n");
+                            return -1;
+                        }
+                        pmouse->endpoint  = endpoint;
+                        pmouse->interface = interface_num;
+                        pmouse->handle    = dev_handle;
+                        pmouse->next      = NULL;
+
+                        if (!list)
+                            list = pmouse;
+                        else
+                        {
+                            pmouse->next = list;
+                            list = pmouse;
+                        }
+                        mouse_cnt++;
+                        break;
+                    }
+                    
+                }
+            }
+
+        }
+
+        libusb_free_config_descriptor(config_desc);
+    }
+
+    *usb_mouse_list = list;
+    return mouse_cnt;
+}
+
+
+static void mouse_irq(struct libusb_transfer *transfer)
+{
+    static int count = 0;
+    if (transfer->status == LIBUSB_TRANSFER_COMPLETED)
+    {
+        /* parser data */
+        printf("%04d datas: ", count++);
+        for (int i = 0; i < transfer->actual_length; i++)
+        {
+            printf("%02x ", transfer->buffer[i]);
+        }
+        printf("\n");
+        
+    }
+
+    if (libusb_submit_transfer(transfer) < 0)
+    {
+        fprintf(stderr, "libusb_submit_transfer err\n");
+    }
+}
+
+int main(int argc, char **argv)
+{
+    int err;
+    libusb_device **devs;
+    int num_devices, num_mouse;
+    struct usb_mouse *pmouse;
+    
+    /* libusb_init */
+
+    err = libusb_init(NULL);
+    if (err < 0) {
+        fprintf(stderr, "failed to initialise libusb %d - %s\n", err, libusb_strerror(err));
+        exit(1);
+    }
+
+    /* get device list */
+    if ((num_devices = libusb_get_device_list(NULL, &devs)) < 0) {
+        fprintf(stderr, "libusb_get_device_list() failed\n");
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "libusb_get_device_list() ok\n");
+
+    /* get usb mouse */
+    num_mouse = get_usb_mouses(devs, num_devices, &usb_mouse_list);
+
+    if (num_mouse <= 0)
+    {
+        /* free device list */
+        libusb_free_device_list(devs, 1);
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "get %d mouses\n", num_mouse);
+
+    /* free device list */
+    libusb_free_device_list(devs, 1);
+
+    /* claim interface */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_set_auto_detach_kernel_driver(pmouse->handle, 1);  
+        err = libusb_claim_interface(pmouse->handle, pmouse->interface);
+        if (err)
+        {
+            fprintf(stderr, "failed to libusb_claim_interface\n");
+            exit(1);
+        }
+        pmouse = pmouse->next;
+    }
+    fprintf(stdout, "libusb_claim_interface ok\n");
+
+    /* for each mouse, alloc transfer, fill transfer, submit transfer */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        /* alloc transfer */
+        pmouse->transfer = libusb_alloc_transfer(0);
+
+        /* fill transfer */
+        libusb_fill_interrupt_transfer(pmouse->transfer, pmouse->handle, pmouse->endpoint, pmouse->buf,
+            sizeof(pmouse->buf), mouse_irq, pmouse, 0);
+
+        /* submit transfer */
+        libusb_submit_transfer(pmouse->transfer);
+        
+        pmouse = pmouse->next;
+    }
+
+    /* handle events */
+    while (1) {
+        struct timeval tv = { 5, 0 };
+        int r;
+
+        r = libusb_handle_events_timeout(NULL, &tv);
+        if (r < 0) {
+            fprintf(stderr, "libusb_handle_events_timeout err\n");
+            break;
+        }
+    }
+    
+
+    /* libusb_close */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_release_interface(pmouse->handle, pmouse->interface);
+        libusb_close(pmouse->handle);        
+        pmouse = pmouse->next;
+    }
+
+    free_usb_mouses(usb_mouse_list);
+    
+    libusb_exit(NULL);
+}
+

README.md

@@ -675,6 +675,13 @@ git clone https://e.coding.net/weidongshan/linux/doc_and_source_for_drivers.git
   07.5_上机实验3_在板上实验
   ```
 
+* 2022.09.28 发布"USB子系统"
+
+  ```shell
+  07.6_使用libusb异步函数读取USB鼠标
+  07.7_异步方式上机实验
+  ```
+
   
 
 

STM32MP157/doc_pic/12_USB/07_使用libusb读取鼠标数据.md

@@ -208,7 +208,149 @@ USB规范里为每个按键定义了16位的按键值，注意：它是16位的
 ### 2.1 编写源码
 
 ```c
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
+#include <libusb-1.0/libusb.h>
+
+int main(int argc, char **argv)
+{
+    int err;
+    libusb_device *dev, **devs;
+    int num_devices;
+    int endpoint;
+    int interface_num;
+    int found = 0;
+    int transferred;
+    int count = 0;
+    unsigned char buffer[16];
+    struct libusb_config_descriptor *config_desc;
+    struct libusb_device_handle *dev_handle = NULL;
+    
+    /* libusb_init */
+
+    err = libusb_init(NULL);
+    if (err < 0) {
+        fprintf(stderr, "failed to initialise libusb %d - %s\n", err, libusb_strerror(err));
+        exit(1);
+    }
+
+    /* get device list */
+    if ((num_devices = libusb_get_device_list(NULL, &devs)) < 0) {
+        fprintf(stderr, "libusb_get_device_list() failed\n");
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "libusb_get_device_list() ok\n");
+
+    /* for each device, get config descriptor */
+    for (int i = 0; i < num_devices; i++) {
+        dev = devs[i];
+
+        /* parse interface descriptor, find usb mouse */        
+        err = libusb_get_config_descriptor(dev, 0, &config_desc);
+        if (err) {
+            fprintf(stderr, "could not get configuration descriptor\n");
+            continue;
+        }
+        fprintf(stdout, "libusb_get_config_descriptor() ok\n");
+
+        for (int interface = 0; interface < config_desc->bNumInterfaces; interface++) {
+            const struct libusb_interface_descriptor *intf_desc = &config_desc->interface[interface].altsetting[0];
+            interface_num = intf_desc->bInterfaceNumber;
+
+            if (intf_desc->bInterfaceClass != 3 || intf_desc->bInterfaceProtocol != 2)
+                continue;
+            else
+            {
+                /* 找到了USB鼠标 */
+                fprintf(stdout, "find usb mouse ok\n");
+                for (int ep = 0; ep < intf_desc->bNumEndpoints; ep++)
+                {
+                    if ((intf_desc->endpoint[ep].bmAttributes & 3) == LIBUSB_TRANSFER_TYPE_INTERRUPT ||
+                            (intf_desc->endpoint[ep].bEndpointAddress & 0x80) == LIBUSB_ENDPOINT_IN) {
+                        /* 找到了输入的中断端点 */
+                        fprintf(stdout, "find in int endpoint\n");
+                        endpoint = intf_desc->endpoint[ep].bEndpointAddress;
+                        found = 1;
+                        break;
+                    }
+                    
+                }
+            }
+
+            if (found)
+                break;
+        }
+
+        libusb_free_config_descriptor(config_desc);
+        
+        if (found)
+            break;        
+    }
+
+    if (!found)
+    {
+        /* free device list */
+        libusb_free_device_list(devs, 1);
+        libusb_exit(NULL);
+        exit(1);
+    }
+
+    if (found)
+    {
+        /* libusb_open */
+        err = libusb_open(dev, &dev_handle);
+        if (err)
+        {
+            fprintf(stderr, "failed to open usb mouse\n");
+            exit(1);
+        }
+        fprintf(stdout, "libusb_open ok\n");
+    }
+
+    /* free device list */
+    libusb_free_device_list(devs, 1);
+
+    /* claim interface */
+    libusb_set_auto_detach_kernel_driver(dev_handle, 1);  
+    err = libusb_claim_interface(dev_handle, interface_num);
+    if (err)
+    {
+        fprintf(stderr, "failed to libusb_claim_interface\n");
+        exit(1);
+    }
+    fprintf(stdout, "libusb_claim_interface ok\n");
+
+    /* libusb_interrupt_transfer */
+    while (1)
+    {
+        err = libusb_interrupt_transfer(dev_handle, endpoint, buffer, 16, &transferred, 5000);
+        if (!err) {
+            /* parser data */
+            printf("%04d datas: ", count++);
+            for (int i = 0; i < transferred; i++)
+            {
+                printf("%02x ", buffer[i]);
+            }
+            printf("\n");
+        } else if (err == LIBUSB_ERROR_TIMEOUT){
+            fprintf(stderr, "libusb_interrupt_transfer timout\n");
+        } else {
+            fprintf(stderr, "libusb_interrupt_transfer err : %d\n", err);
+            //exit(1);
+        }
+        
+    }
+
+    /* libusb_close */
+    libusb_release_interface(dev_handle, interface_num);
+    libusb_close(dev_handle);
+    libusb_exit(NULL);
+}
 ```
 
 
@@ -230,7 +372,7 @@ gcc -o readmouse readmouse.c -lusb-1.0
 
 
 
-#### 2.2.2 在开发板上实验
+#### 2.2.2 在IMX6ULL开发板上实验
 
 
 
@@ -269,13 +411,295 @@ gcc -o readmouse readmouse.c -lusb-1.0
 * 交叉编译app
 
   ```shell
-  arm-buildroot-linux-gnueabihf-gcc -o readmouse readmouse.c -lusb-1.0
+  arm-buildroot-linux-gnueabihf-gcc -o  readmouse.c -lusb-1.0
+  ```
+
+
+* 在开发板上插入USB鼠标，执行命令
+
+  ```shell
+  ./readmouse
   ```
 
   
 
 
 
+#### 2.2.3 在STM32MP157开发板上实验
+
+* STM32MP157的工具链里已经含有libusb，所以无需交叉编译、安装libusb
+
+* 交叉编译app
+
+  ```shell
+  arm-buildroot-linux-gnueabihf-gcc -o readmouse readmouse.c -lusb-1.0
+  ```
+
+* 在开发板上插入USB鼠标，执行命令
+
+  ```shell
+  ./readmouse
+  ```
+
+  
+
+
+
+## 3. 使用异步接口读取鼠标数据
+
+源码在GIT仓库如下位置：
+
+![image-20220929092859668](pic/61_libusb_async_usbmouse_src.png)
+
+### 3.1 编写源码
+
+```c
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libusb-1.0/libusb.h>
+
+struct usb_mouse {
+    struct libusb_device_handle *handle;
+    int interface;
+    int endpoint;
+    unsigned char buf[16];
+    int transferred;
+    struct libusb_transfer *transfer;
+    struct usb_mouse *next;
+};
+
+static struct usb_mouse *usb_mouse_list;
+
+
+void free_usb_mouses(struct usb_mouse *usb_mouse_list)
+{
+    struct usb_mouse *pnext;
+    while (usb_mouse_list)
+    {
+        pnext = usb_mouse_list->next;
+        free(usb_mouse_list);
+        usb_mouse_list = pnext;
+    }
+}
+
+
+/*  */
+int get_usb_mouses(libusb_device **devs, int num_devices, struct usb_mouse **usb_mouse_list)
+{
+    int err;
+    libusb_device *dev;
+    int endpoint;
+    int interface_num;
+    struct libusb_config_descriptor *config_desc;
+    struct libusb_device_handle *dev_handle = NULL;
+    struct usb_mouse *pmouse;
+    struct usb_mouse *list = NULL;
+    int mouse_cnt = 0;
+
+    /* for each device, get config descriptor */
+    for (int i = 0; i < num_devices; i++) {
+        dev = devs[i];
+
+        /* parse interface descriptor, find usb mouse */        
+        err = libusb_get_config_descriptor(dev, 0, &config_desc);
+        if (err) {
+            fprintf(stderr, "could not get configuration descriptor\n");
+            continue;
+        }
+        fprintf(stdout, "libusb_get_config_descriptor() ok\n");
+
+        for (int interface = 0; interface < config_desc->bNumInterfaces; interface++) {
+            const struct libusb_interface_descriptor *intf_desc = &config_desc->interface[interface].altsetting[0];
+            interface_num = intf_desc->bInterfaceNumber;
+
+            if (intf_desc->bInterfaceClass != 3 || intf_desc->bInterfaceProtocol != 2)
+                continue;
+            else
+            {
+                /* 找到了USB鼠标 */
+                fprintf(stdout, "find usb mouse ok\n");
+                for (int ep = 0; ep < intf_desc->bNumEndpoints; ep++)
+                {
+                    if ((intf_desc->endpoint[ep].bmAttributes & 3) == LIBUSB_TRANSFER_TYPE_INTERRUPT ||
+                            (intf_desc->endpoint[ep].bEndpointAddress & 0x80) == LIBUSB_ENDPOINT_IN) {
+                        /* 找到了输入的中断端点 */
+                        fprintf(stdout, "find in int endpoint\n");
+                        endpoint = intf_desc->endpoint[ep].bEndpointAddress;
+
+                        /* libusb_open */
+                        err = libusb_open(dev, &dev_handle);
+                        if (err)
+                        {
+                            fprintf(stderr, "failed to open usb mouse\n");
+                            return -1;
+                        }
+                        fprintf(stdout, "libusb_open ok\n");
+
+                        /* 记录下来: 放入链表 */
+                        pmouse = malloc(sizeof(struct usb_mouse));
+                        if (!pmouse)
+                        {
+                            fprintf(stderr, "can not malloc\n");
+                            return -1;
+                        }
+                        pmouse->endpoint  = endpoint;
+                        pmouse->interface = interface_num;
+                        pmouse->handle    = dev_handle;
+                        pmouse->next      = NULL;
+
+                        if (!list)
+                            list = pmouse;
+                        else
+                        {
+                            pmouse->next = list;
+                            list = pmouse;
+                        }
+                        mouse_cnt++;
+                        break;
+                    }
+                    
+                }
+            }
+
+        }
+
+        libusb_free_config_descriptor(config_desc);
+    }
+
+    *usb_mouse_list = list;
+    return mouse_cnt;
+}
+
+
+static void mouse_irq(struct libusb_transfer *transfer)
+{
+    static int count = 0;
+    if (transfer->status == LIBUSB_TRANSFER_COMPLETED)
+    {
+        /* parser data */
+        printf("%04d datas: ", count++);
+        for (int i = 0; i < transfer->actual_length; i++)
+        {
+            printf("%02x ", transfer->buffer[i]);
+        }
+        printf("\n");
+        
+    }
+
+    if (libusb_submit_transfer(transfer) < 0)
+    {
+        fprintf(stderr, "libusb_submit_transfer err\n");
+    }
+}
+
+int main(int argc, char **argv)
+{
+    int err;
+    libusb_device **devs;
+    int num_devices, num_mouse;
+    struct usb_mouse *pmouse;
+    
+    /* libusb_init */
+
+    err = libusb_init(NULL);
+    if (err < 0) {
+        fprintf(stderr, "failed to initialise libusb %d - %s\n", err, libusb_strerror(err));
+        exit(1);
+    }
+
+    /* get device list */
+    if ((num_devices = libusb_get_device_list(NULL, &devs)) < 0) {
+        fprintf(stderr, "libusb_get_device_list() failed\n");
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "libusb_get_device_list() ok\n");
+
+    /* get usb mouse */
+    num_mouse = get_usb_mouses(devs, num_devices, &usb_mouse_list);
+
+    if (num_mouse <= 0)
+    {
+        /* free device list */
+        libusb_free_device_list(devs, 1);
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "get %d mouses\n", num_mouse);
+
+    /* free device list */
+    libusb_free_device_list(devs, 1);
+
+    /* claim interface */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_set_auto_detach_kernel_driver(pmouse->handle, 1);  
+        err = libusb_claim_interface(pmouse->handle, pmouse->interface);
+        if (err)
+        {
+            fprintf(stderr, "failed to libusb_claim_interface\n");
+            exit(1);
+        }
+        pmouse = pmouse->next;
+    }
+    fprintf(stdout, "libusb_claim_interface ok\n");
+
+    /* for each mouse, alloc transfer, fill transfer, submit transfer */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        /* alloc transfer */
+        pmouse->transfer = libusb_alloc_transfer(0);
+
+        /* fill transfer */
+        libusb_fill_interrupt_transfer(pmouse->transfer, pmouse->handle, pmouse->endpoint, pmouse->buf,
+            sizeof(pmouse->buf), mouse_irq, pmouse, 0);
+
+        /* submit transfer */
+        libusb_submit_transfer(pmouse->transfer);
+        
+        pmouse = pmouse->next;
+    }
+
+    /* handle events */
+    while (1) {
+        struct timeval tv = { 5, 0 };
+        int r;
+
+        r = libusb_handle_events_timeout(NULL, &tv);
+        if (r < 0) {
+            fprintf(stderr, "libusb_handle_events_timeout err\n");
+            break;
+        }
+    }
+    
+
+    /* libusb_close */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_release_interface(pmouse->handle, pmouse->interface);
+        libusb_close(pmouse->handle);        
+        pmouse = pmouse->next;
+    }
+
+    free_usb_mouses(usb_mouse_list);
+    
+    libusb_exit(NULL);
+}
+```
+
+
+
+
+
+### 3.2 在开发板上实验
+
 
 
 

STM32MP157/source/A7/12_USB/03_libusb_mouse_async/readmouse.c

@@ -0,0 +1,240 @@
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libusb-1.0/libusb.h>
+
+struct usb_mouse {
+    struct libusb_device_handle *handle;
+    int interface;
+    int endpoint;
+    unsigned char buf[16];
+    int transferred;
+    struct libusb_transfer *transfer;
+    struct usb_mouse *next;
+};
+
+static struct usb_mouse *usb_mouse_list;
+
+
+void free_usb_mouses(struct usb_mouse *usb_mouse_list)
+{
+    struct usb_mouse *pnext;
+    while (usb_mouse_list)
+    {
+        pnext = usb_mouse_list->next;
+        free(usb_mouse_list);
+        usb_mouse_list = pnext;
+    }
+}
+
+
+/*  */
+int get_usb_mouses(libusb_device **devs, int num_devices, struct usb_mouse **usb_mouse_list)
+{
+    int err;
+    libusb_device *dev;
+    int endpoint;
+    int interface_num;
+    struct libusb_config_descriptor *config_desc;
+    struct libusb_device_handle *dev_handle = NULL;
+    struct usb_mouse *pmouse;
+    struct usb_mouse *list = NULL;
+    int mouse_cnt = 0;
+
+    /* for each device, get config descriptor */
+    for (int i = 0; i < num_devices; i++) {
+        dev = devs[i];
+
+        /* parse interface descriptor, find usb mouse */        
+        err = libusb_get_config_descriptor(dev, 0, &config_desc);
+        if (err) {
+            fprintf(stderr, "could not get configuration descriptor\n");
+            continue;
+        }
+        fprintf(stdout, "libusb_get_config_descriptor() ok\n");
+
+        for (int interface = 0; interface < config_desc->bNumInterfaces; interface++) {
+            const struct libusb_interface_descriptor *intf_desc = &config_desc->interface[interface].altsetting[0];
+            interface_num = intf_desc->bInterfaceNumber;
+
+            if (intf_desc->bInterfaceClass != 3 || intf_desc->bInterfaceProtocol != 2)
+                continue;
+            else
+            
+{
+                /* 找到了USB鼠标 */
+                fprintf(stdout, "find usb mouse ok\n");
+                for (int ep = 0; ep < intf_desc->bNumEndpoints; ep++)
+                {
+                    if ((intf_desc->endpoint[ep].bmAttributes & 3) == LIBUSB_TRANSFER_TYPE_INTERRUPT ||
+                            (intf_desc->endpoint[ep].bEndpointAddress & 0x80) == LIBUSB_ENDPOINT_IN) {
+                        /* 找到了输入的中断端点 */
+                        fprintf(stdout, "find in int endpoint\n");
+                        endpoint = intf_desc->endpoint[ep].bEndpointAddress;
+
+                        /* libusb_open */
+                        err = libusb_open(dev, &dev_handle);
+                        if (err)
+                        {
+                            fprintf(stderr, "failed to open usb mouse\n");
+                            return -1;
+                        }
+                        fprintf(stdout, "libusb_open ok\n");
+
+                        /* 记录下来: 放入链表 */
+                        pmouse = malloc(sizeof(struct usb_mouse));
+                        if (!pmouse)
+                        {
+                            fprintf(stderr, "can not malloc\n");
+                            return -1;
+                        }
+                        pmouse->endpoint  = endpoint;
+                        pmouse->interface = interface_num;
+                        pmouse->handle    = dev_handle;
+                        pmouse->next      = NULL;
+
+                        if (!list)
+                            list = pmouse;
+                        else
+                        {
+                            pmouse->next = list;
+                            list = pmouse;
+                        }
+                        mouse_cnt++;
+                        break;
+                    }
+                    
+                }
+            }
+
+        }
+
+        libusb_free_config_descriptor(config_desc);
+    }
+
+    *usb_mouse_list = list;
+    return mouse_cnt;
+}
+
+
+static void mouse_irq(struct libusb_transfer *transfer)
+{
+    static int count = 0;
+    if (transfer->status == LIBUSB_TRANSFER_COMPLETED)
+    {
+        /* parser data */
+        printf("%04d datas: ", count++);
+        for (int i = 0; i < transfer->actual_length; i++)
+        {
+            printf("%02x ", transfer->buffer[i]);
+        }
+        printf("\n");
+        
+    }
+
+    if (libusb_submit_transfer(transfer) < 0)
+    {
+        fprintf(stderr, "libusb_submit_transfer err\n");
+    }
+}
+
+int main(int argc, char **argv)
+{
+    int err;
+    libusb_device **devs;
+    int num_devices, num_mouse;
+    struct usb_mouse *pmouse;
+    
+    /* libusb_init */
+
+    err = libusb_init(NULL);
+    if (err < 0) {
+        fprintf(stderr, "failed to initialise libusb %d - %s\n", err, libusb_strerror(err));
+        exit(1);
+    }
+
+    /* get device list */
+    if ((num_devices = libusb_get_device_list(NULL, &devs)) < 0) {
+        fprintf(stderr, "libusb_get_device_list() failed\n");
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "libusb_get_device_list() ok\n");
+
+    /* get usb mouse */
+    num_mouse = get_usb_mouses(devs, num_devices, &usb_mouse_list);
+
+    if (num_mouse <= 0)
+    {
+        /* free device list */
+        libusb_free_device_list(devs, 1);
+        libusb_exit(NULL);
+        exit(1);
+    }
+    fprintf(stdout, "get %d mouses\n", num_mouse);
+
+    /* free device list */
+    libusb_free_device_list(devs, 1);
+
+    /* claim interface */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_set_auto_detach_kernel_driver(pmouse->handle, 1);  
+        err = libusb_claim_interface(pmouse->handle, pmouse->interface);
+        if (err)
+        {
+            fprintf(stderr, "failed to libusb_claim_interface\n");
+            exit(1);
+        }
+        pmouse = pmouse->next;
+    }
+    fprintf(stdout, "libusb_claim_interface ok\n");
+
+    /* for each mouse, alloc transfer, fill transfer, submit transfer */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        /* alloc transfer */
+        pmouse->transfer = libusb_alloc_transfer(0);
+
+        /* fill transfer */
+        libusb_fill_interrupt_transfer(pmouse->transfer, pmouse->handle, pmouse->endpoint, pmouse->buf,
+            sizeof(pmouse->buf), mouse_irq, pmouse, 0);
+
+        /* submit transfer */
+        libusb_submit_transfer(pmouse->transfer);
+        
+        pmouse = pmouse->next;
+    }
+
+    /* handle events */
+    while (1) {
+        struct timeval tv = { 5, 0 };
+        int r;
+
+        r = libusb_handle_events_timeout(NULL, &tv);
+        if (r < 0) {
+            fprintf(stderr, "libusb_handle_events_timeout err\n");
+            break;
+        }
+    }
+    
+
+    /* libusb_close */
+    pmouse = usb_mouse_list;
+    while (pmouse)
+    {
+        libusb_release_interface(pmouse->handle, pmouse->interface);
+        libusb_close(pmouse->handle);        
+        pmouse = pmouse->next;
+    }
+
+    free_usb_mouses(usb_mouse_list);
+    
+    libusb_exit(NULL);
+}
+