1 files changed, 22 insertions, 2 deletions

diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 62a35822003e..fd877f633dd2 100644
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -1055,6 +1055,8 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq)
 {
 	struct mmc_spi_host	*host = mmc_priv(mmc);
 	int			status = -EINVAL;
+	int			crc_retry = 5;
+	struct mmc_command	stop;
 
 #ifdef DEBUG
 	/* MMC core and layered drivers *MUST* issue SPI-aware commands */
@@ -1087,10 +1089,29 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq)
 	/* request exclusive bus access */
 	spi_bus_lock(host->spi->master);
 
+crc_recover:
 	/* issue command; then optionally data and stop */
 	status = mmc_spi_command_send(host, mrq, mrq->cmd, mrq->data != NULL);
 	if (status == 0 && mrq->data) {
 		mmc_spi_data_do(host, mrq->cmd, mrq->data, mrq->data->blksz);
+
+		/*
+		 * The SPI bus is not always reliable for large data transfers.
+		 * If an occasional crc error is reported by the SD device with
+		 * data read/write over SPI, it may be recovered by repeating
+		 * the last SD command again. The retry count is set to 5 to
+		 * ensure the driver passes stress tests.
+		 */
+		if (mrq->data->error == -EILSEQ && crc_retry) {
+			stop.opcode = MMC_STOP_TRANSMISSION;
+			stop.arg = 0;
+			stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
+			status = mmc_spi_command_send(host, mrq, &stop, 0);
+			crc_retry--;
+			mrq->data->error = 0;
+			goto crc_recover;
+		}
+
 		if (mrq->stop)
 			status = mmc_spi_command_send(host, mrq, mrq->stop, 0);
 		else
@@ -1345,8 +1366,7 @@ static int mmc_spi_probe(struct spi_device *spi)
 
 	mmc->ops = &mmc_spi_ops;
 	mmc->max_blk_size = MMC_SPI_BLOCKSIZE;
-	mmc->max_hw_segs = MMC_SPI_BLOCKSATONCE;
-	mmc->max_phys_segs = MMC_SPI_BLOCKSATONCE;
+	mmc->max_segs = MMC_SPI_BLOCKSATONCE;
 	mmc->max_req_size = MMC_SPI_BLOCKSATONCE * MMC_SPI_BLOCKSIZE;
 	mmc->max_blk_count = MMC_SPI_BLOCKSATONCE;