cvs_read_i2c
ret = cvs_read_i2c(ctx, n.cmd_id, &n.resp.state, sizeof(n.resp.state));
ret = cvs_read_i2c(ctx, n.cmd_id, &n.resp.cap, sizeof(n.resp.cap));
ret = cvs_read_i2c(ctx, cmd, &resp, sizeof(resp));
ret = cvs_read_i2c(ctx, cmd,