From eea0f581c4e596e02250df230f8d385827977964 Mon Sep 17 00:00:00 2001 From: Pierre Ossman Date: Sat, 28 Jun 2008 13:22:40 +0200 Subject: [PATCH] sdio: clean up handling of byte mode transfer size Make sure that the maximum size for a byte mode transfer is identical in all places. Also tweak the transfer helper so that a single byte mode transfer is preferred over (possibly multiple) block mode request(s). Signed-off-by: Pierre Ossman --- drivers/mmc/core/sdio_io.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) diff --git a/drivers/mmc/core/sdio_io.c b/drivers/mmc/core/sdio_io.c index 6ee7861fcea..cc42a41ff6a 100644 --- a/drivers/mmc/core/sdio_io.c +++ b/drivers/mmc/core/sdio_io.c @@ -186,9 +186,20 @@ int sdio_set_block_size(struct sdio_func *func, unsigned blksz) func->cur_blksize = blksz; return 0; } - EXPORT_SYMBOL_GPL(sdio_set_block_size); +/* + * Calculate the maximum byte mode transfer size + */ +static inline unsigned int sdio_max_byte_size(struct sdio_func *func) +{ + return min(min(min( + func->card->host->max_seg_size, + func->card->host->max_blk_size), + func->max_blksize), + 512u); /* maximum size for byte mode */ +} + /** * sdio_align_size - pads a transfer size to a more optimal value * @func: SDIO function @@ -222,7 +233,7 @@ unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz) * If we can still do this with just a byte transfer, then * we're done. */ - if ((sz <= func->cur_blksize) && (sz <= 512)) + if (sz <= sdio_max_byte_size(func)) return sz; if (func->card->cccr.multi_block) { @@ -253,7 +264,7 @@ unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz) */ byte_sz = mmc_align_data_size(func->card, sz % func->cur_blksize); - if ((byte_sz <= func->cur_blksize) && (byte_sz <= 512)) { + if (byte_sz <= sdio_max_byte_size(func)) { blk_sz = sz / func->cur_blksize; return blk_sz * func->cur_blksize + byte_sz; } @@ -263,8 +274,8 @@ unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz) * controller can handle the chunk size; */ chunk_sz = mmc_align_data_size(func->card, - min(func->cur_blksize, 512u)); - if (chunk_sz == min(func->cur_blksize, 512u)) { + sdio_max_byte_size(func)); + if (chunk_sz == sdio_max_byte_size(func)) { /* * Fix up the size of the remainder (if any) */ @@ -296,7 +307,7 @@ static int sdio_io_rw_ext_helper(struct sdio_func *func, int write, int ret; /* Do the bulk of the transfer using block mode (if supported). */ - if (func->card->cccr.multi_block) { + if (func->card->cccr.multi_block && (size > sdio_max_byte_size(func))) { /* Blocks per command is limited by host count, host transfer * size (we only use a single sg entry) and the maximum for * IO_RW_EXTENDED of 511 blocks. */ @@ -328,11 +339,7 @@ static int sdio_io_rw_ext_helper(struct sdio_func *func, int write, /* Write the remainder using byte mode. */ while (remainder > 0) { - size = remainder; - if (size > func->cur_blksize) - size = func->cur_blksize; - if (size > 512) - size = 512; /* maximum size for byte mode */ + size = min(remainder, sdio_max_byte_size(func)); ret = mmc_io_rw_extended(func->card, write, func->num, addr, incr_addr, buf, 1, size); -- 2.41.1