host->wait = USDHI6_WAIT_FOR_STOP;
                        return 0;
                }
-               /* Unsupported STOP command */
+               /* fall through - Unsupported STOP command. */
        default:
                dev_err(mmc_dev(host->mmc),
                        "unsupported stop CMD%d for CMD%d\n",
        switch (host->wait) {
        default:
                dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
-               /* mrq can be NULL in this actually impossible case */
+               /* fall through - mrq can be NULL, but is impossible. */
        case USDHI6_WAIT_FOR_CMD:
                usdhi6_error_code(host);
                if (mrq)
                        host->offset, data->blocks, data->blksz, data->sg_len,
                        sg_dma_len(sg), sg->offset);
                usdhi6_sg_unmap(host, true);
-               /*
-                * If USDHI6_WAIT_FOR_DATA_END times out, we have already unmapped
-                * the page
-                */
+               /* fall through - page unmapped in USDHI6_WAIT_FOR_DATA_END. */
        case USDHI6_WAIT_FOR_DATA_END:
                usdhi6_error_code(host);
                data->error = -ETIMEDOUT;