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>
This commit is contained in:
David Vrabel 2007-08-08 14:24:21 +01:00 committed by Pierre Ossman
parent 9a08f82b3c
commit eb65946892
3 changed files with 86 additions and 28 deletions

View file

@ -189,6 +189,67 @@ int sdio_set_block_size(struct sdio_func *func, unsigned blksz)
EXPORT_SYMBOL_GPL(sdio_set_block_size);
/* Split an arbitrarily sized data transfer into several
* IO_RW_EXTENDED commands. */
static int sdio_io_rw_ext_helper(struct sdio_func *func, int write,
unsigned addr, int incr_addr, u8 *buf, unsigned size)
{
unsigned remainder = size;
unsigned max_blocks;
int ret;
/* Do the bulk of the transfer using block mode (if supported). */
if (func->card->cccr.multi_block) {
/* 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. */
max_blocks = min(min(
func->card->host->max_blk_count,
func->card->host->max_seg_size / func->cur_blksize),
511u);
while (remainder > func->cur_blksize) {
unsigned blocks;
blocks = remainder / func->cur_blksize;
if (blocks > max_blocks)
blocks = max_blocks;
size = blocks * func->cur_blksize;
ret = mmc_io_rw_extended(func->card, write,
func->num, addr, incr_addr, buf,
blocks, func->cur_blksize);
if (ret)
return ret;
remainder -= size;
buf += size;
if (incr_addr)
addr += size;
}
}
/* 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 */
ret = mmc_io_rw_extended(func->card, write, func->num, addr,
incr_addr, buf, 1, size);
if (ret)
return ret;
remainder -= size;
buf += size;
if (incr_addr)
addr += size;
}
return 0;
}
/**
* sdio_readb - read a single byte from a SDIO function
* @func: SDIO function to access
@ -252,15 +313,13 @@ EXPORT_SYMBOL_GPL(sdio_writeb);
* @addr: address to begin reading from
* @count: number of bytes to read
*
* Reads up to 512 bytes from the address space of a given SDIO
* function. Return value indicates if the transfer succeeded or
* not.
* Reads from the address space of a given SDIO function. Return
* value indicates if the transfer succeeded or not.
*/
int sdio_memcpy_fromio(struct sdio_func *func, void *dst,
unsigned int addr, int count)
{
return mmc_io_rw_extended(func->card, 0, func->num, addr, 0, dst,
count);
return sdio_io_rw_ext_helper(func, 0, addr, 1, dst, count);
}
EXPORT_SYMBOL_GPL(sdio_memcpy_fromio);
@ -271,15 +330,13 @@ EXPORT_SYMBOL_GPL(sdio_memcpy_fromio);
* @src: buffer that contains the data to write
* @count: number of bytes to write
*
* Writes up to 512 bytes to the address space of a given SDIO
* function. Return value indicates if the transfer succeeded or
* not.
* Writes to the address space of a given SDIO function. Return
* value indicates if the transfer succeeded or not.
*/
int sdio_memcpy_toio(struct sdio_func *func, unsigned int addr,
void *src, int count)
{
return mmc_io_rw_extended(func->card, 1, func->num, addr, 0, src,
count);
return sdio_io_rw_ext_helper(func, 1, addr, 1, src, count);
}
EXPORT_SYMBOL_GPL(sdio_memcpy_toio);
@ -290,15 +347,13 @@ EXPORT_SYMBOL_GPL(sdio_memcpy_toio);
* @addr: address of (single byte) FIFO
* @count: number of bytes to read
*
* Reads up to 512 bytes from the specified FIFO of a given SDIO
* function. Return value indicates if the transfer succeeded or
* not.
* Reads from the specified FIFO of a given SDIO function. Return
* value indicates if the transfer succeeded or not.
*/
int sdio_readsb(struct sdio_func *func, void *dst, unsigned int addr,
int count)
{
return mmc_io_rw_extended(func->card, 0, func->num, addr, 1, dst,
count);
return sdio_io_rw_ext_helper(func, 0, addr, 0, dst, count);
}
EXPORT_SYMBOL_GPL(sdio_readsb);
@ -310,15 +365,13 @@ EXPORT_SYMBOL_GPL(sdio_readsb);
* @src: buffer that contains the data to write
* @count: number of bytes to write
*
* Writes up to 512 bytes to the specified FIFO of a given SDIO
* function. Return value indicates if the transfer succeeded or
* not.
* Writes to the specified FIFO of a given SDIO function. Return
* value indicates if the transfer succeeded or not.
*/
int sdio_writesb(struct sdio_func *func, unsigned int addr, void *src,
int count)
{
return mmc_io_rw_extended(func->card, 1, func->num, addr, 1, src,
count);
return sdio_io_rw_ext_helper(func, 1, addr, 0, src, count);
}
EXPORT_SYMBOL_GPL(sdio_writesb);

View file

@ -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);

View file

@ -16,7 +16,7 @@ int mmc_send_io_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr);
int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
unsigned addr, u8 in, u8* out);
int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
unsigned addr, int bang, u8 *data, unsigned size);
unsigned addr, int incr_addr, u8 *buf, unsigned blocks, unsigned blksz);
#endif