大多数情况下，Linux系统都带有手柄驱动模块joydev，当我们插上设备的时候可以通过以下指令查看是否检测到该设备
ls /dev/或者ls /dev/input/
如果有出现 js0 的设备，则证明设备能正常使用
如果没有 js0 设备，可以通过以下指令安装驱动
sudo modprobe joydev
如果提示没有找到该模块则是内核中没有添加该驱动，需手动加载驱动进内核。
正常使用手柄后我们可以使用 joystick 软件来进行测试，使用以下指令进行安装
sudo apt-get install joystick
安装完后，启动软件进行测试
jstest /dev/js0或者jstest /dev/input/js0
以上是使用软件进行游戏手柄的测试，在更多时候我们是需要其输出相关信息，下面介绍使用程序将游戏手柄的数据输出：
因为Linux中的list.h不能直接用，所以我们把它单独提出来，建立一个listop.c文件和listop.h文件
/*listop.c*/#include "listop.h" static void __check_head(struct list_head* head) { if ((head->next == 0) && (head->prev == 0)) { INIT_LIST_HEAD(head); } } /* * Insert a new entry between two known consecutive entries. * * This is only for internal list manipulation where we know * the prev/next entries already! */ static void __list_add(struct list_head* new, struct list_head* prev, struct list_head* next) { next->prev = new; new->next = next; new->prev = prev; prev->next = new; } /* * Delete a list entry by making the prev/next entries * point to each other. * * This is only for internal list manipulation where we know * the prev/next entries already! */ static void __list_del(struct list_head* prev, struct list_head* next) { next->prev = prev; prev->next = next; } /** * list_add - add a new entry * @new: new entry to be added * @head: list head to add it after * * Insert a new entry after the specified head. * This is good for implementing stacks. */ void list_add(struct list_head* new, struct list_head* head) { __check_head(head); __list_add(new, head, head->next); } /** * list_add_tail - add a new entry * @new: new entry to be added * @head: list head to add it before * * Insert a new entry before the specified head. * This is useful for implementing queues. */ void list_add_tail(struct list_head* new, struct list_head* head) { __check_head(head); __list_add(new, head->prev, head); } /** * list_del - deletes entry from list. * @entry: the element to delete from the list. * Note: list_empty on entry does not return true after this, the entry is in an undefined state. */ void list_del(struct list_head* entry) { __list_del(entry->prev, entry->next); } /** * list_del_init - deletes entry from list and reinitialize it. * @entry: the element to delete from the list. */ void list_del_init(struct list_head* entry) { __list_del(entry->prev, entry->next); INIT_LIST_HEAD(entry); } /** * list_move - delete from one list and add as another's head * @list: the entry to move * @head: the head that will precede our entry */ void list_move(struct list_head* list, struct list_head* head) { __check_head(head); __list_del(list->prev, list->next); list_add(list, head); } /** * list_move_tail - delete from one list and add as another's tail * @list: the entry to move * @head: the head that will follow our entry */ void list_move_tail(struct list_head* list, struct list_head* head) { __check_head(head); __list_del(list->prev, list->next); list_add_tail(list, head); } /** * list_splice - join two lists * @list: the new list to add. * @head: the place to add it in the first list. */ void list_splice(struct list_head* list, struct list_head* head) { struct list_head* first = list; struct list_head* last = list->prev; struct list_head* at = head->next; first->prev = head; head->next = first; last->next = at; at->prev = last; } struct list_head* list_dequeue( struct list_head* list ) { struct list_head* next, *prev, *result = ((void*)0); prev = list; next = prev->next; if ( next != prev ) { result = next; next = next->next; next->prev = prev; prev->next = next; result->prev = result->next = result; } return result; }
/*listop.h*/#ifndef LISTOP_H #define LISTOP_H #ifdef __cplusplusextern "C"#endifstruct list_head { struct list_head *next, *prev; }; typedef struct list_head list_t; #define LIST_HEAD_INIT(name) { &(name), &(name) } #define LIST_HEAD(name)struct list_head name = LIST_HEAD_INIT(name) #define INIT_LIST_HEAD(ptr) do { (ptr)->next = (ptr); (ptr)->prev = (ptr); } while (0) /** * list_add - add a new entry * @new: new entry to be added * @head: list head to add it after * * Insert a new entry after the specified head. * This is good for implementing stacks. */ void list_add(struct list_head *new, struct list_head *head); /** * list_add_tail - add a new entry * @new: new entry to be added * @head: list head to add it before * * Insert a new entry before the specified head. * This is useful for implementing queues. */ void list_add_tail(struct list_head *new, struct list_head *head); /** * list_del - deletes entry from list. * @entry: the element to delete from the list. * Note: list_empty on entry does not return true after this, the entry is in an undefined state. */ void list_del(struct list_head *entry); /** * list_del_init - deletes entry from list and reinitialize it. * @entry: the element to delete from the list. */ void list_del_init(struct list_head *entry); /** * list_move - delete from one list and add as another's head * @list: the entry to move * @head: the head that will precede our entry */ void list_move(struct list_head *list, struct list_head *head); /** * list_move_tail - delete from one list and add as another's tail * @list: the entry to move * @head: the head that will follow our entry */ void list_move_tail(struct list_head *list, struct list_head *head); /** * list_splice - join two lists * @list: the new list to add. * @head: the place to add it in the first list. */ void list_splice(struct list_head *list, struct list_head *head); /** * list_empty - tests whether a list is empty * @head: the list to test. */ static int list_empty(struct list_head *head) { return head->next == head; } /** * list_dequeue - dequeue the head of the list if there are more than one entry * @list: the list to dequeue */ struct list_head * list_dequeue( struct list_head *list ); /** * list_entry - get the struct for this entry * @ptr: the &struct list_head pointer. * @type: the type of the struct this is embedded in. * @member: the name of the list_struct within the struct. */ #define list_entry(ptr, type, member)((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member))) /** * list_for_each - iterate over a list * @pos: the &struct list_head to use as a loop counter. * @head: the head for your list. */ #define list_for_each(pos, head)for (pos = (head)->next; pos != (head); pos = pos->next) /** * list_for_each_safe - iterate over a list safe against removal of list entry * @pos: the &struct list_head to use as a loop counter. * @n:another &struct list_head to use as temporary storage * @head: the head for your list. */ #define list_for_each_safe(pos, n, head)for (pos = (head)->next, n = pos->next; pos != (head); pos = n, n = pos->next) /** * list_for_each_prev - iterate over a list in reverse order * @pos: the &struct list_head to use as a loop counter. * @head: the head for your list. */ #define list_for_each_prev(pos, head)for (pos = (head)->prev; pos != (head); pos = pos->prev) /** * list_for_each_entry - iterate over list of given type * @pos: the type * to use as a loop counter. * @head: the head for your list. * @member: the name of the list_struct within the struct. */ #define list_for_each_entry(pos, head, member) for (pos = list_entry((head)->next, typeof(*pos), member); &pos->member != (head); pos = list_entry(pos->member.next, typeof(*pos), member)) #endif
以下是执行程序
/*joystick.c*/#include <stdio.h>#include <sys/types.h>#include <sys/time.h>#include <sys/stat.h>#include <fcntl.h>#include <unistd.h>#include <errno.h>#include <stdlib.h>#include <string.h>#include <linux/joystick.h>#include "listop.h"#include "Recv.h"#if 1#define LOG_DBG(fmt, ...) fprintf(stdout, fmt, ##__VA_ARGS__)#else#define LOG_DBG(fmt, ...)#endif#define LOG_ERR(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__)typedef struct _joy_stick_ctx {struct list_head list;int i4_js_fd;unsigned int i4_op_block;} JOYSTICK_CTX_T;LIST_HEAD(_t_js_ctx_head);/*==> struct list_head _t_js_ctx_head = {&_t_js_ctx_head, &_t_js_ctx_head};*/int joystick_open(char* cp_js_dev_name, int i4_block){int i4_open_flags = O_RDONLY;JOYSTICK_CTX_T* pt_joystick_ctx = NULL;if (!cp_js_dev_name) {LOG_ERR("[%s] js device name is NULL\n", __func__);return -1;}pt_joystick_ctx = (JOYSTICK_CTX_T*)calloc(sizeof(JOYSTICK_CTX_T), 1);if (!pt_joystick_ctx) {LOG_ERR("[%s] no memory!!\n", __func__);return -1;}pt_joystick_ctx->i4_op_block = i4_block ? 1 : 0;if (pt_joystick_ctx->i4_op_block == 0) {i4_open_flags |= O_NONBLOCK;}pt_joystick_ctx->i4_js_fd = open(cp_js_dev_name, i4_open_flags);if (pt_joystick_ctx->i4_js_fd < 0) {LOG_ERR("[%s] open device %s error\n", __func__, cp_js_dev_name);free(pt_joystick_ctx);return -1;}list_add_tail(&pt_joystick_ctx->list, &_t_js_ctx_head);return pt_joystick_ctx->i4_js_fd;}int joystick_close(int i4_fd){struct list_head* pt_entry;struct list_head* pt_next;JOYSTICK_CTX_T* pt_node;if (list_empty(&_t_js_ctx_head)) {LOG_ERR("[%s] device not opened\n", __func__);return -1;}list_for_each_safe(pt_entry, pt_next, &_t_js_ctx_head) {pt_node = list_entry(pt_entry, JOYSTICK_CTX_T, list);if (pt_node->i4_js_fd == i4_fd) {list_del_init(&pt_node->list);free(pt_node);return close(i4_fd);}}LOG_ERR("[%s] i4_fd=%d invalid\n", __func__, i4_fd);return -1;}int joystick_read_one_event(int i4_fd, struct js_event* tp_jse){int i4_rd_bytes;/*do not check i4_fd again*/i4_rd_bytes = read(i4_fd, tp_jse, sizeof(struct js_event));if (i4_rd_bytes == -1) {if (errno == EAGAIN) { /*when no block, it is not error*/return 0;}else {return -1;}}return i4_rd_bytes;}int joystick_read_ready(int i4_fd){int i4_block = 2;struct list_head* pt_entry;JOYSTICK_CTX_T* pt_node;if (list_empty(&_t_js_ctx_head)) {LOG_ERR("[%s] device not opened\n", __func__);return -1;}list_for_each(pt_entry, &_t_js_ctx_head) {pt_node = list_entry(pt_entry, JOYSTICK_CTX_T, list);if (pt_node->i4_js_fd == i4_fd) {i4_block = pt_node->i4_op_block;break;}}if (i4_block == 2) {LOG_ERR("[%s] i4_fd=%d invalid\n", __func__, i4_fd);return 0;}else if (i4_block == 1) {fd_set readfd;int i4_ret = 0;struct timeval timeout = {0, 0};FD_ZERO(&readfd);FD_SET(i4_fd, &readfd);i4_ret = select(i4_fd + 1, &readfd, NULL, NULL, &timeout);if (i4_ret > 0 && FD_ISSET(i4_fd, &readfd)) {return 1;}else {return 0;}}return 1; /*noblock read, aways ready*/}void debug_list(void){char s_char[128];int i = 0;if (! list_empty(&_t_js_ctx_head)) {struct list_head* pt_entry;JOYSTICK_CTX_T* pt_node;list_for_each(pt_entry, &_t_js_ctx_head) {pt_node = list_entry(pt_entry, JOYSTICK_CTX_T, list);LOG_DBG("fd:%d--block:%d\n", pt_node->i4_js_fd, pt_node->i4_op_block);}}else {LOG_DBG("-----------> EMPTY NOW\n");}}#if 1typedef struct _axes_t {int x;int y;} AXES_T;int main(){int fd, rc;char number_of_axes = 0;char number_of_btns = 0;char c_re[15][30];char js_name_str[128];unsigned int buttons_state = 0;AXES_T* tp_axes = NULL;int i, print_init_stat = 0;char but_sta = 0;char start_state = 0;struct js_event jse;fd = joystick_open("/dev/input/js0", 1);if (fd < 0){LOG_ERR("open failed.\n");exit(1);}if( SerialInit() == -1 ){perror("SerialInit Error!\n");return NULL;}rc = ioctl(fd, JSIOCGAXES, &number_of_axes);if (rc != -1){LOG_DBG("number_of_axes:%d\n", number_of_axes);if (number_of_axes > 0)tp_axes = (AXES_T*)calloc(sizeof(AXES_T), 1);}rc = ioctl(fd, JSIOCGBUTTONS, &number_of_btns);if (rc != -1){LOG_DBG("number_of_btns:%d\n", number_of_btns);}if (ioctl(fd, JSIOCGNAME(sizeof(js_name_str)), js_name_str) < 0){LOG_DBG(js_name_str, "Unknown", sizeof(js_name_str));}LOG_DBG("joystick Name: %s\n", js_name_str);while(1){if (joystick_read_ready(fd)){rc = joystick_read_one_event(fd, &jse);if (rc > 0){if ((jse.type & JS_EVENT_INIT) == JS_EVENT_INIT){if ((jse.type & ~JS_EVENT_INIT) == JS_EVENT_BUTTON){if (jse.value)buttons_state |= (1 << jse.number);elsebuttons_state &= ~(1 << jse.number);}else if ((jse.type & ~JS_EVENT_INIT) == JS_EVENT_AXIS){if (tp_axes){if ((jse.number & 1) == 0)tp_axes[jse.number / 2].x = jse.value;elsetp_axes[jse.number / 2].y = jse.value;}}}else{if (print_init_stat == 0) //设备输出初始信息{for (i = 0; i < number_of_btns; i++){sprintf(c_re[i], "but%d %d;", i, ((buttons_state & (1 << i)) == (1 << i)) ? 0 : 1);LOG_DBG(c_re[i]);//LOG_DBG(" %d", i);LOG_DBG("joystick init state: button %d is %s.\n", i, ((buttons_state & (1 << i)) == (1 << i)) ? "DOWN" : "UP");}if (tp_axes)for (i = 0; i < number_of_axes; i++) {sprintf(c_re[i+11], "axes%d x=%d y=%d;", i, tp_axes[i].x, tp_axes[i].y);LOG_DBG(c_re[i+11]);//LOG_DBG(" %d", i+11);LOG_DBG("joystick init state: axes %d is x=%d y=%d.\n", i, tp_axes[i].x, tp_axes[i].y);}//ready = 1;print_init_stat = 1;}if (jse.type == JS_EVENT_BUTTON) //按键状态改变时输出相关信息{if (jse.value)buttons_state |= (1 << jse.number);elsebuttons_state &= ~(1 << jse.number);//LOG_DBG("joystick state: button %d is %s.\n", jse.number, ((buttons_state & (1 << jse.number)) == (1 << jse.number)) ? "DOWN" : "UP");bzero( c_re[jse.number], sizeof(c_re[jse.number]) );but_sta = ((buttons_state & (1 << jse.number)) == (1 << jse.number)) ? 0 : 1;sprintf(c_re[jse.number], "but%d %d;", jse.number, but_sta);LOG_DBG("%s \n", c_re[jse.number]);// jse.number为手柄按键序号 but_sta为按键当前状态}else if (jse.type == JS_EVENT_AXIS) //手杆状态改变时输出相关信息{if (tp_axes){if ((jse.number & 1) == 0)tp_axes[jse.number / 2].x = jse.value;elsetp_axes[jse.number / 2].y = jse.value;bzero( c_re[jse.number / 2 +11], sizeof(c_re[jse.number / 2 +11]) );sprintf(c_re[jse.number / 2 +11], "axes%d x=%d y=%d;", jse.number / 2, tp_axes[jse.number / 2].x, tp_axes[jse.number / 2].y);LOG_DBG("%s \n", c_re[jse.number / 2 +11]);//tp_axes[jse.number / 2] jse.number/2为手杆序号 .x .y分别对应手杆当前x轴和y轴的值}else{LOG_DBG("joystick state: axes %d is %s=%d.\n", jse.number / 2, ((jse.number & 1) == 0) ? "x" : "y", jse.value);}}}}}}joystick_close(fd);if (tp_axes) {free(tp_axes);}return 0;}#endif
