sdio: extend sdio_readsb() and friends to handle any length of buffer

Extend sdio_readsb(), sdio_writesb(), sdio_memcpy_fromio(), and
sdio_memcpy_toio() to handle any length of buffer by splitting the transfer
into several IO_RW_EXTENDED commands. Typically, a transfer would be split
into a single block mode transfer followed by a byte mode transfer for the
remainder but we also handle lack of block mode support and the block size
being greater than 512 (the maximum byte mode transfer size).

host->max_seg_size <= host->max_req_size so there's no need to check both
when determining the maximum data size for a single command.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

1 files changed, 12 insertions, 7 deletions

diff --git a/drivers/mmc/core/sdio_ops.c b/drivers/mmc/core/sdio_ops.c
index 4f2c77139477..98e20532452a 100644
--- a/drivers/mmc/core/sdio_ops.c
+++ b/drivers/mmc/core/sdio_ops.c
@@ -88,7 +88,7 @@ int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
 }
 
 int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
-        unsigned addr, int bang, u8 *buf, unsigned size)
+        unsigned addr, int incr_addr, u8 *buf, unsigned blocks, unsigned blksz)
 {
         struct mmc_request mrq;
         struct mmc_command cmd;
@@ -97,7 +97,9 @@ int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
 
         BUG_ON(!card);
         BUG_ON(fn > 7);
-        BUG_ON(size > 512);
+        BUG_ON(blocks == 1 && blksz > 512);
+        WARN_ON(blocks == 0);
+        WARN_ON(blksz == 0);
 
         memset(&mrq, 0, sizeof(struct mmc_request));
         memset(&cmd, 0, sizeof(struct mmc_command));
@@ -109,18 +111,21 @@ int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
         cmd.opcode = SD_IO_RW_EXTENDED;
         cmd.arg = write ? 0x80000000 : 0x00000000;
         cmd.arg |= fn << 28;
-        cmd.arg |= bang ? 0x00000000 : 0x04000000;
+        cmd.arg |= incr_addr ? 0x04000000 : 0x00000000;
         cmd.arg |= addr << 9;
-        cmd.arg |= (size == 512) ? 0 : size;
+        if (blocks == 1 && blksz <= 512)
+                cmd.arg |= (blksz == 512) ? 0 : blksz;  /* byte mode */
+        else
+                cmd.arg |= 0x08000000 | blocks;         /* block mode */
         cmd.flags = MMC_RSP_R5 | MMC_CMD_ADTC;
 
-        data.blksz = size;
-        data.blocks = 1;
+        data.blksz = blksz;
+        data.blocks = blocks;
         data.flags = write ? MMC_DATA_WRITE : MMC_DATA_READ;
         data.sg = &sg;
         data.sg_len = 1;
 
-        sg_init_one(&sg, buf, size);
+        sg_init_one(&sg, buf, blksz * blocks);
 
         mmc_set_data_timeout(&data, card);