hciattach.c 分析

原文地址：external/bluetooth/bluez/Tools/hciattach.c作者：xxha000721

external/bluetooth/bluez/Tools/hciattach.c 会生成 hciattach, 会被install 到 /system/bin/hciattach 

1. 先介绍一个数据结构 uart_t ：

struct uart_t {

    char *type;  //name，这里为texas

    int m_id;

    int p_id;

    int proto;

    int init_speed; //波特率

    int speed;

    int flags;   //UART 标志位

    char *bdaddr;

    int (*init)(int fd,struct uart_t *u,struct termios *ti);  //u -> init，这里为texas

    int (*post)(int fd,struct uart_t *u,struct termios *ti);  //u -> post，这里为texas2

};
 2. 各种 BT 模块的 uart 参数配置：

struct uart_t uart[]= {

    { "any", 0x0000, 0x0000, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, NULL },

    { "ericsson", 0x0000, 0x0000, HCI_UART_H4, 57600, 115200, FLOW_CTL,NULL, ericsson},

    { "digi", 0x0000, 0x0000, HCI_UART_H4, 9600, 115200, FLOW_CTL,NULL, digi },



    { "bcsp", 0x0000, 0x0000, HCI_UART_BCSP, 115200, 115200, 0,NULL, bcsp },



    /* Xircom PCMCIA cards: Credit Card Adapter and Real Port Adapter */

    { "xircom", 0x0105, 0x080a, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, NULL },



    /* CSR Casira serial adapter or BrainBoxes serial dongle (BL642) */

    { "csr", 0x0000, 0x0000, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, csr },



    /* BrainBoxes PCMCIA card (BL620) */

    { "bboxes", 0x0160, 0x0002, HCI_UART_H4, 115200, 460800, FLOW_CTL,NULL, csr },



    /* Silicon Wave kits */

    { "swave", 0x0000, 0x0000, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, swave},



    /* Texas Instruments Bluelink (BRF) modules */

    { "texas", 0x0000, 0x0000, HCI_UART_LL, 115200, 115200, FLOW_CTL, NULL, texas, texas2},   //这里就用的这项数据。

    { "texasalt", 0x0000, 0x0000, HCI_UART_LL, 115200, 115200, FLOW_CTL, NULL, texasalt,NULL },



    /* ST Microelectronics minikits based on STLC2410/STLC2415 */

    { "st", 0x0000, 0x0000, HCI_UART_H4, 57600, 115200, FLOW_CTL,NULL, st },



    /* ST Microelectronics minikits based on STLC2500 */

    { "stlc2500", 0x0000, 0x0000, HCI_UART_H4, 115200, 115200, FLOW_CTL,"00:80:E1:00:AB:BA", stlc2500},



    /* Philips generic Ericsson IP core based */

    { "philips", 0x0000, 0x0000, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, NULL },



    /* Philips BGB2xx Module */

    { "bgb2xx", 0x0000, 0x0000, HCI_UART_H4, 115200, 115200, FLOW_CTL,"BD:B2:10:00:AB:BA", bgb2xx},



    /* Sphinx Electronics PICO Card */

    { "picocard", 0x025e, 0x1000, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, NULL },



    /* Inventel BlueBird Module */

    { "inventel", 0x0000, 0x0000, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, NULL },



    /* COM One Platinium Bluetooth PC Card */

    { "comone", 0xffff, 0x0101, HCI_UART_BCSP, 115200, 115200, 0,NULL, bcsp },



    /* TDK Bluetooth PC Card and IBM Bluetooth PC Card II */

    { "tdk", 0x0105, 0x4254, HCI_UART_BCSP, 115200, 115200, 0,NULL, bcsp },



    /* Socket Bluetooth CF Card (Rev G) */

    { "socket", 0x0104, 0x0096, HCI_UART_BCSP, 230400, 230400, 0,NULL, bcsp },



    /* 3Com Bluetooth Card (Version 3.0) */

    { "3com", 0x0101, 0x0041, HCI_UART_H4, 115200, 115200, FLOW_CTL,NULL, csr },



    /* AmbiCom BT2000C Bluetooth PC/CF Card */

    { "bt2000c", 0x022d, 0x2000, HCI_UART_H4, 57600, 460800, FLOW_CTL,NULL, csr },



    /* Zoom Bluetooth PCMCIA Card */

    { "zoom", 0x0279, 0x950b, HCI_UART_BCSP, 115200, 115200, 0,NULL, bcsp },



    /* Sitecom CN-504 PCMCIA Card */

    { "sitecom", 0x0279, 0x950b, HCI_UART_BCSP, 115200, 115200, 0,NULL, bcsp },



    /* Billionton PCBTC1 PCMCIA Card */

    { "billionton", 0x0279, 0x950b, HCI_UART_BCSP, 115200, 115200, 0,NULL, bcsp },



    /* Broadcom BCM2035 */

    { "bcm2035", 0x0A5C, 0x2035, HCI_UART_H4, 115200, 460800, FLOW_CTL,NULL, bcm2035},



    { NULL, 0}

};
  3. main() 函数：

int main(int argc,char *argv[])

{

    struct uart_t *u = NULL;

    int detach, printpid, raw, opt, i, n, ld, err;

    int to = 10;

    int init_speed = 0;

    int send_break = 0;

    pid_t pid;

    struct sigaction sa;

    struct pollfd p;

    sigset_t sigs;

    char dev[PATH_MAX];



    detach = 1;

    printpid = 0;

    raw = 0;



    while ((opt=getopt(argc, argv,"bnpt:s:lr"))!= EOF){  //解析参数

        switch(opt){

        case 'b':

            send_break = 1;

            break;



        case 'n':  // 比如 有 -n 参数就会进这里

            detach = 0;

            break;



        case 'p':

            printpid = 1;

            break;



        case 't':

            to = atoi(optarg);

            break;



        case 's':

            init_speed = atoi(optarg);

            break;



        case 'l':

            for (i = 0; uart[i].type; i++){

                printf("%-10s0x%04x,0x%04x\n", uart[i].type,

                            uart[i].m_id, uart[i].p_id);

            }

            exit(0);



        case 'r':

            raw = 1;

            break;



        default:

            usage();

            exit(1);

        }

    }



    n = argc - optind;

    if (n< 2) {

        usage();

        exit(1);

    }



    for (n= 0; optind< argc; n++, optind++){

        char *opt;



        opt = argv[optind];



        switch(n){

        case 0:

            dev[0]= 0;

            if (!strchr(opt,'/'))    //opt = /dev/ttyO1

                strcpy(dev,"/dev/");

            strcat(dev, opt);        //strcat之后，dev =/dev/ttyO1

            break;



        case 1:

            if (strchr(argv[optind],',')){

                int m_id, p_id;

                sscanf(argv[optind],"%x,%x", &m_id, &p_id);

                u = get_by_id(m_id, p_id);

            } else {

                u = get_by_type(opt); //如果参数有/dev/ttyO1,就会这里得到uart_t u 

            }



            if (!u){

                fprintf(stderr,"Unknown device type or id\n");

                exit(1);

            }



            break;



        case 2:

            u->speed= atoi(argv[optind]); //这里获得波特率参数。

            break;



        case 3:

            if (!strcmp("flow", argv[optind]))

                u->flags|= FLOW_CTL;    //uart flag 流控制标志

            else

                u->flags&= ~FLOW_CTL;

            break;



        case 4:

            u->bdaddr= argv[optind];

            break;

        }

    }



    if (!u){

        fprintf(stderr,"Unknown device type or id\n");

        exit(1);

    }



    /* If user specified a initial speed, use that instead of

     the hardware's default */

    if (init_speed)

        u->init_speed= init_speed;    //波特率



    memset(&sa, 0,sizeof(sa));

    sa.sa_flags = SA_NOCLDSTOP;

    sa.sa_handler = sig_alarm;        //sig_alarm = Initialization time out

    sigaction(SIGALRM,&sa, NULL);     //sigaction 超时后就会 打印出该sa_handler.



    /* 10 seconds should be enough for initialization */

    alarm(to);

    bcsp_max_retries = to;



    n = init_uart(dev, u, send_break, raw);  //这里会进入init_uart,初始化串口。

    if (n< 0) {

        perror("Can't initialize device");

        exit(1);

    }



    printf("Device setup complete\n");



    alarm(0);



    memset(&sa, 0,sizeof(sa));

    sa.sa_flags = SA_NOCLDSTOP;

    sa.sa_handler = SIG_IGN;

    sigaction(SIGCHLD,&sa, NULL);

    sigaction(SIGPIPE,&sa, NULL);



    sa.sa_handler = sig_term;

    sigaction(SIGTERM,&sa, NULL);

    sigaction(SIGINT,&sa, NULL);



    sa.sa_handler = sig_hup;

    sigaction(SIGHUP,&sa, NULL);



    if (detach){

        if ((pid= fork())){

            if (printpid)

                printf("%d\n", pid);

            return 0;

        }



        for (i= 0; i < 20; i++)

            if (i != n)

                close(i);

    }



    p.fd = n;

    p.events = POLLERR| POLLHUP;



    sigfillset(&sigs);

    sigdelset(&sigs, SIGCHLD);

    sigdelset(&sigs, SIGPIPE);

    sigdelset(&sigs, SIGTERM);

    sigdelset(&sigs, SIGINT);

    sigdelset(&sigs, SIGHUP);



    while (!__io_canceled){

        p.revents = 0;

        err = ppoll(&p, 1,NULL, &sigs);

        if (err< 0 && errno== EINTR)

            continue;

        if (err)

            break;

    }



    /* Restore TTY line discipline */

    ld = N_TTY;

    if (ioctl(n, TIOCSETD,&ld) < 0) {

        perror("Can't restore line discipline");

        exit(1);

    }



    return 0;

}
 4.get_by_id() / get_by_type():

static struct uart_t * get_by_id(int m_id,int p_id)

{

    int i;

    for (i= 0; uart[i].type; i++){

        if (uart[i].m_id== m_id && uart[i].p_id== p_id)

            return &uart[i];

    }

    return NULL;

}



static struct uart_t* get_by_type(char*type)

{

    int i;

    for (i= 0; uart[i].type; i++){

        if (!strcmp(uart[i].type,type))//获取/dev/ttyO1

            return &uart[i];

    }

    return NULL;

}
 5.init_uart():

/* Initialize UART driver */

static int init_uart(char*dev, struct uart_t *u,int send_break,int raw)

{

    struct termios ti;

    int fd, i;

    unsigned long flags = 0;



    if (raw)

        flags |= 1<< HCI_UART_RAW_DEVICE;



    fd = open(dev, O_RDWR| O_NOCTTY); //打开 /dev/ttyO1

    if (fd< 0) {

        perror("Can't open serial port");

        return -1;

    }



    tcflush(fd, TCIOFLUSH);    //一系列 UART 口配置



    if (tcgetattr(fd,&ti) < 0) {

        perror("Can't get port settings");

        return -1;

    }



    cfmakeraw(&ti);         



    ti.c_cflag |= CLOCAL;

    if (u->flags& FLOW_CTL)     //添加流控制标志

        ti.c_cflag |= CRTSCTS;

    else

        ti.c_cflag &= ~CRTSCTS;



    if (tcsetattr(fd, TCSANOW,&ti) < 0) {

        perror("Can't set port settings");

        return -1;

    }



    /* Set initial baudrate */

    if (set_speed(fd,&ti, u->init_speed)< 0) {  //初始波特率设置

        perror("Can't set initial baud rate");

        return -1;

    }



    tcflush(fd, TCIOFLUSH);



    if (send_break){

        tcsendbreak(fd, 0);

        usleep(500000);

    }



    if (u->init&& u->init(fd, u,&ti) < 0)   //这里调用texas()函数

        return -1;



    tcflush(fd, TCIOFLUSH);



    /* Set actual baudrate */

    if (set_speed(fd,&ti, u->speed)< 0) {  //实际波特率设置

        perror("Can't set baud rate");

        return -1;

    }



    /* Set TTY to N_HCI line discipline */

    i = N_HCI;

    if (ioctl(fd, TIOCSETD,&i) < 0) {

        perror("Can't set line discipline");

        return -1;

    }



    if (flags&& ioctl(fd, HCIUARTSETFLAGS, flags)< 0) {

        perror("Can't set UART flags");

        return -1;

    }



    if (ioctl(fd, HCIUARTSETPROTO, u->proto)< 0) {

        perror("Can't set device");

        return -1;

    }



    if (u->post&& u->post(fd, u,&ti) < 0)   //一切正常的话，就运行texas2()

        return -1;



    return fd;

}
 6. texas 相关的一系列函数，这个被定义在 hciattach_ti.c 中：

static int texas(int fd,struct uart_t *u,struct termios *ti)

{

 return texas_init(fd, ti);

}

static int texas2(int fd,struct uart_t *u,struct termios *ti)

{

 return texas_post(fd, ti);

}

static int texasalt(int fd,struct uart_t *u,struct termios *ti)

{

 return texasalt_init(fd, u->speed, ti);

}
   7. 这个代码中，还有其他公司的一些接口，如爱立信，BCM，st等等