mmc_block: hard code 512 byte block size

We use 512 byte blocks on all cards, and newer cards support nothing
else, so hard code it and make the code less complex.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index d73cac8..1d1e469 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -57,7 +57,6 @@
 	struct mmc_queue queue;
 
 	unsigned int	usage;
-	unsigned int	block_bits;
 	unsigned int	read_only;
 };
 
@@ -231,11 +230,11 @@
 		if (!mmc_card_blockaddr(card))
 			brq.cmd.arg <<= 9;
 		brq.cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
-		brq.data.blksz = 1 << md->block_bits;
+		brq.data.blksz = 512;
 		brq.stop.opcode = MMC_STOP_TRANSMISSION;
 		brq.stop.arg = 0;
 		brq.stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
-		brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
+		brq.data.blocks = req->nr_sectors;
 
 		if (brq.data.blocks > 1) {
 			/* SPI multiblock writes terminate using a special
@@ -351,16 +350,11 @@
 	if (rq_data_dir(req) != READ) {
 		if (mmc_card_sd(card)) {
 			u32 blocks;
-			unsigned int bytes;
 
 			blocks = mmc_sd_num_wr_blocks(card);
 			if (blocks != (u32)-1) {
-				if (card->csd.write_partial)
-					bytes = blocks << md->block_bits;
-				else
-					bytes = blocks << 9;
 				spin_lock_irq(&md->lock);
-				ret = __blk_end_request(req, 0, bytes);
+				ret = __blk_end_request(req, 0, blocks << 9);
 				spin_unlock_irq(&md->lock);
 			}
 		} else {
@@ -410,13 +404,6 @@
 	 */
 	md->read_only = mmc_blk_readonly(card);
 
-	/*
-	 * Both SD and MMC specifications state (although a bit
-	 * unclearly in the MMC case) that a block size of 512
-	 * bytes must always be supported by the card.
-	 */
-	md->block_bits = 9;
-
 	md->disk = alloc_disk(1 << MMC_SHIFT);
 	if (md->disk == NULL) {
 		ret = -ENOMEM;
@@ -454,7 +441,7 @@
 
 	sprintf(md->disk->disk_name, "mmcblk%d", devidx);
 
-	blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
+	blk_queue_hardsect_size(md->queue.queue, 512);
 
 	if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
 		/*
@@ -492,7 +479,7 @@
 
 	mmc_claim_host(card->host);
 	cmd.opcode = MMC_SET_BLOCKLEN;
-	cmd.arg = 1 << md->block_bits;
+	cmd.arg = 512;
 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
 	err = mmc_wait_for_cmd(card->host, &cmd, 5);
 	mmc_release_host(card->host);