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>
diff --git a/drivers/net/wireless/libertas/if_sdio.c b/drivers/net/wireless/libertas/if_sdio.c
index 3dd537b..b54e2ea 100644
--- a/drivers/net/wireless/libertas/if_sdio.c
+++ b/drivers/net/wireless/libertas/if_sdio.c
@@ -1,7 +1,7 @@
/*
* linux/drivers/net/wireless/libertas/if_sdio.c
*
- * Copyright 2007 Pierre Ossman
+ * Copyright 2007-2008 Pierre Ossman
*
* Inspired by if_cs.c, Copyright 2007 Holger Schurig
*
@@ -266,13 +266,10 @@
/*
* The transfer must be in one transaction or the firmware
- * goes suicidal.
+ * goes suicidal. There's no way to guarantee that for all
+ * controllers, but we can at least try.
*/
- chunk = size;
- if ((chunk > card->func->cur_blksize) || (chunk > 512)) {
- chunk = (chunk + card->func->cur_blksize - 1) /
- card->func->cur_blksize * card->func->cur_blksize;
- }
+ chunk = sdio_align_size(card->func, size);
ret = sdio_readsb(card->func, card->buffer, card->ioport, chunk);
if (ret)
@@ -696,13 +693,10 @@
/*
* The transfer must be in one transaction or the firmware
- * goes suicidal.
+ * goes suicidal. There's no way to guarantee that for all
+ * controllers, but we can at least try.
*/
- size = nb + 4;
- if ((size > card->func->cur_blksize) || (size > 512)) {
- size = (size + card->func->cur_blksize - 1) /
- card->func->cur_blksize * card->func->cur_blksize;
- }
+ size = sdio_align_size(card->func, nb + 4);
packet = kzalloc(sizeof(struct if_sdio_packet) + size,
GFP_ATOMIC);