1 files changed, 23 insertions, 7 deletions

diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 62a35822003e..7c1e16aaf17f 100644
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -99,7 +99,7 @@
 #define r1b_timeout             (HZ * 3)
 
 /* One of the critical speed parameters is the amount of data which may
- * be transfered in one command. If this value is too low, the SD card
+ * be transferred in one command. If this value is too low, the SD card
  * controller has to do multiple partial block writes (argggh!). With
  * today (2008) SD cards there is little speed gain if we transfer more
  * than 64 KBytes at a time. So use this value until there is any indication
@@ -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;
 
@@ -1496,21 +1516,17 @@ static int __devexit mmc_spi_remove(struct spi_device *spi)
         return 0;
 }
 
-#if defined(CONFIG_OF)
 static struct of_device_id mmc_spi_of_match_table[] __devinitdata = {
         { .compatible = "mmc-spi-slot", },
         {},
 };
-#endif
 
 static struct spi_driver mmc_spi_driver = {
         .driver = {
                 .name =         "mmc_spi",
                 .bus =          &spi_bus_type,
                 .owner =        THIS_MODULE,
-#if defined(CONFIG_OF)
                 .of_match_table = mmc_spi_of_match_table,
-#endif
         },
         .probe =        mmc_spi_probe,
         .remove =       __devexit_p(mmc_spi_remove),