mmc,sdio: helper function for transfer padding

There are a lot of crappy controllers out there that cannot handle
all the request sizes that the MMC/SD/SDIO specifications require.
In case the card driver can pad the data to overcome the problems,
this commit adds a helper that calculates how much that padding
should be.

A corresponding helper is also added for SDIO, but it can also deal
with all the complexities of splitting up a large transfer efficiently.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

2 files changed, 4 insertions, 1 deletions

diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index d0c3abed74c2..143cebf0586f 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -135,6 +135,7 @@ extern int mmc_wait_for_app_cmd(struct mmc_host *, struct mmc_card *,
         struct mmc_command *, int);
 
 extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *);
+extern unsigned int mmc_align_data_size(struct mmc_card *, unsigned int);
 
 extern int __mmc_claim_host(struct mmc_host *host, atomic_t *abort);
 extern void mmc_release_host(struct mmc_host *host);
diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h
index b050f4d7b41f..f57f22b3be88 100644
--- a/include/linux/mmc/sdio_func.h
+++ b/include/linux/mmc/sdio_func.h
@@ -1,7 +1,7 @@
 /*
  *  include/linux/mmc/sdio_func.h
  *
- *  Copyright 2007 Pierre Ossman
+ *  Copyright 2007-2008 Pierre Ossman
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -120,6 +120,8 @@ extern int sdio_set_block_size(struct sdio_func *func, unsigned blksz);
 extern int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler);
 extern int sdio_release_irq(struct sdio_func *func);
 
+extern unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz);
+
 extern unsigned char sdio_readb(struct sdio_func *func,
         unsigned int addr, int *err_ret);
 extern unsigned short sdio_readw(struct sdio_func *func,