omap_hsmmc: fix scatter-gather list sanity checking

Do not use host->dma_len when it is uninitialzed.  Finish the request with
an error if the mmc_omap_prepare_data() fails.
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/mmc/host/omap_hsmmc.c

@@ -878,7 +878,7 @@ mmc_omap_start_dma_transfer(struct mmc_omap_host *host, struct mmc_request *req)
 	struct mmc_data *data = req->data;
 
 	/* Sanity check: all the SG entries must be aligned by block size. */
-	for (i = 0; i < host->dma_len; i++) {
+	for (i = 0; i < data->sg_len; i++) {
 		struct scatterlist *sgl;
 
 		sgl = data->sg + i;
@@ -1021,10 +1021,20 @@ static int omap_mmc_disable(struct mmc_host *mmc, int lazy)
 static void omap_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
 {
 	struct mmc_omap_host *host = mmc_priv(mmc);
+	int err;
 
 	WARN_ON(host->mrq != NULL);
 	host->mrq = req;
-	mmc_omap_prepare_data(host, req);
+	err = mmc_omap_prepare_data(host, req);
+	if (err) {
+		req->cmd->error = err;
+		if (req->data)
+			req->data->error = err;
+		host->mrq = NULL;
+		mmc_request_done(mmc, req);
+		return;
+	}
+
 	mmc_omap_start_command(host, req->cmd, req->data);
 }