sd_read_data
cmd->error = sd_read_data(host, cmd, (u16)data->blksz, buf,
err = sd_read_data(host, &cmd, 0x40, NULL, 0, 100);
cmd->error = sd_read_data(host, cmd, (u16)data->blksz, buf,
err = sd_read_data(host, &cmd, 0x40, NULL, 0, 100);