static int rx8025_get_datetime(struct i2c_client *client, struct rtc_time *tm) { unsigned char date[7]; int data, err; //init rx8025 i2c_smbus_write_byte_data(client, RX8025_REG_CTRL1,0x20); i2c_smbus_write_byte_data(client, RX8025_REG_CTRL2,0x20); /* Now read time and date */ data = i2c_smbus_read_byte_data(client, RX8025_REG_SC) & 0x7f; if (data < 0) { dev_err(&client->dev, "Unable to read second\n"); return -EIO; } tm->tm_sec = bcd2bin(data); data = i2c_smbus_read_byte_data(client, RX8025_REG_MN) & 0x7f; if (data < 0) { dev_err(&client->dev, "Unable to read min\n"); return -EIO; } tm->tm_min = bcd2bin(data); data = i2c_smbus_read_byte_data(client, RX8025_REG_HR); if (data < 0) { dev_err(&client->dev, "Unable to read hour\n"); return -EIO; }
我加载了一个rtc设备的驱动后,这样的提示是什么原因导致的呢?Input/output error