diff options
Diffstat (limited to 'drivers/mmc/card/block.c')
| -rw-r--r-- | drivers/mmc/card/block.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 3d067c35185d..a2a81f38ec10 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -236,6 +236,19 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req) brq.stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC; brq.data.blocks = req->nr_sectors; + /* + * @BUG: The block-layer is able to modify the minimum number of + * transfer blocks for one request (see [1]). At this moment, it sets + * this number to eigth, which is a problem for controllers that only + * supports single-transfers. + * + * [1] block/blk-settings.c:blk_queue_max_sectors() + * + * (Luis Galdos) + */ + if (brq.data.blocks > card->host->max_blk_count) + brq.data.blocks = card->host->max_blk_count; + if (brq.data.blocks > 1) { /* SPI multiblock writes terminate using a special * token, not a STOP_TRANSMISSION request. @@ -266,6 +279,27 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req) mmc_queue_bounce_pre(mq); + /* + * Adjust the sg list so it is the same size as the + * request. + * @BUG: See above description (Luis Galdos) + */ + if (brq.data.blocks != req->nr_sectors) { + int data_size, i; + struct scatterlist *sg; + + data_size = brq.data.blocks * brq.data.blksz; + for_each_sg(brq.data.sg, sg, brq.data.sg_len, i) { + data_size -= sg->length; + if (data_size <= 0) { + sg->length += data_size; + i++; + break; + } + } + brq.data.sg_len = i; + } + mmc_wait_for_req(card->host, &brq.mrq); mmc_queue_bounce_post(mq); |