[問題] 請教 i2c 的連續讀取

[weishiang (wei)]

請教一下在 linux 上要如何連續讀取 i2c 的資料呢?
目前都只能一次讀取 1 byte , my code :
struct i2c_msg  msg[2];
struct i2c_rdwr_ioctl_data queue;
uint8_t *buf;
uint8_t *buf2;
buf = (uint8_t*) malloc(sizeof(uint8_t) * 1);
buf[0] = 0x00;
buf2 = (uint8_t*) malloc(sizeof(uint8_t) * 32);
buf[0] = 0xff;//test:
queue.msgs = msg;
queue.nmsgs = 2;
queue.msgs[0].len = (len+1);
queue.msgs[0].addr = DevAddr_list[bus_idx];
queue.msgs[0].flags = 0;
queue.msgs[0].buf = buf; // read address of i2c client

queue.msgs[1].len = len;
queue.msgs[1].addr = DevAddr_list[bus_idx];
queue.msgs[1].flags = I2C_M_RD;
queue.msgs[1].buf = buf2

ret = ioctl(fd, I2C_RDWR, (uint32_t)&queue);
if (ret < 0) {
        printf("Error dring I2C_RDWR ioctl with error code: %d\n", ret);
        return ret;
}


thank you!

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◆ From: 61.218.111.194
※ 編輯: weishiang       來自: 61.218.111.194       (12/02 16:57)
→ bluestar8783:為啥不用i2c_master_send/i2c_master_recv???
推 eleghost:他這是ap層的code, 難道len加大不能讀更多byte嗎?
→ weishiang:謝謝eleghost提醒,只查r/w的code忘記看傳過來的參數值@@