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 <drzeus@drzeus.cx>
This commit is contained in:
Pierre Ossman 2008-06-28 13:22:40 +02:00
parent ad3868b2ec
commit eea0f581c4

View File

@ -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);