- 根目录:
- drivers
- mmc
- core
- sdio_io.c
/*
* linux/drivers/mmc/core/sdio_io.c
*
* 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
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*/
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/sdio_func.h>
#include "sdio_ops.h"
/**
* sdio_claim_host - exclusively claim a bus for a certain SDIO function
* @func: SDIO function that will be accessed
*
* Claim a bus for a set of operations. The SDIO function given
* is used to figure out which bus is relevant.
*/
void sdio_claim_host(struct sdio_func *func)
{
BUG_ON(!func);
BUG_ON(!func->card);
mmc_claim_host(func->card->host);
}
EXPORT_SYMBOL_GPL(sdio_claim_host);
/**
* sdio_release_host - release a bus for a certain SDIO function
* @func: SDIO function that was accessed
*
* Release a bus, allowing others to claim the bus for their
* operations.
*/
void sdio_release_host(struct sdio_func *func)
{
BUG_ON(!func);
BUG_ON(!func->card);
mmc_release_host(func->card->host);
}
EXPORT_SYMBOL_GPL(sdio_release_host);
/**
* sdio_enable_func - enables a SDIO function for usage
* @func: SDIO function to enable
*
* Powers up and activates a SDIO function so that register
* access is possible.
*/
int sdio_enable_func(struct sdio_func *func)
{
int ret;
unsigned char reg;
unsigned long timeout;
BUG_ON(!func);
BUG_ON(!func->card);
pr_debug("SDIO: Enabling device %s...\n", sdio_func_id(func));
ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IOEx, 0, ®);
if (ret)
goto err;
reg |= 1 << func->num;
ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IOEx, reg, NULL);
if (ret)
goto err;
timeout = jiffies + msecs_to_jiffies(func->enable_timeout);
while (1) {
ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IORx, 0, ®);
if (ret)
goto err;
if (reg & (1 << func->num))
break;
ret = -ETIME;
if (time_after(jiffies, timeout))
goto err;
}
pr_debug("SDIO: Enabled device %s\n", sdio_func_id(func));
return 0;
err:
pr_debug("SDIO: Failed to enable device %s\n", sdio_func_id(func));
return ret;
}
EXPORT_SYMBOL_GPL(sdio_enable_func);
/**
* sdio_disable_func - disable a SDIO function
* @func: SDIO function to disable
*
* Powers down and deactivates a SDIO function. Register access
* to this function will fail until the function is reenabled.
*/
int sdio_disable_func(struct sdio_func *func)
{
int ret;
unsigned char reg;
BUG_ON(!func);
BUG_ON(!func->card);
pr_debug("SDIO: Disabling device %s...\n", sdio_func_id(func));
ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IOEx, 0, ®);
if (ret)
goto err;
reg &= ~(1 << func->num);
ret = mmc_io_rw_direct(func->card, 1, 0, SDIO_CCCR_IOEx, reg, NULL);
if (ret)
goto err;
pr_debug("SDIO: Disabled device %s\n", sdio_func_id(func));
return 0;
err:
pr_debug("SDIO: Failed to disable device %s\n", sdio_func_id(func));
return -EIO;
}
EXPORT_SYMBOL_GPL(sdio_disable_func);
/**
* sdio_set_block_size - set the block size of an SDIO function
* @func: SDIO function to change
* @blksz: new block size or 0 to use the default.
*
* The default block size is the largest supported by both the function
* and the host, with a maximum of 512 to ensure that arbitrarily sized
* data transfer use the optimal (least) number of commands.
*
* A driver may call this to override the default block size set by the
* core. This can be used to set a block size greater than the maximum
* that reported by the card; it is the driver's responsibility to ensure
* it uses a value that the card supports.
*
* Returns 0 on success, -EINVAL if the host does not support the
* requested block size, or -EIO (etc.) if one of the resultant FBR block
* size register writes failed.
*
*/
int sdio_set_block_size(struct sdio_func *func, unsigned blksz)
{
int ret;
if (blksz > func->card->host->max_blk_size)
return -EINVAL;
if (blksz == 0) {
blksz = min(func->max_blksize, func->card->host->max_blk_size);
blksz = min(blksz, 512u);
}
ret = mmc_io_rw_direct(func->card, 1, 0,
SDIO_FBR_BASE(func->num) + SDIO_FBR_BLKSIZE,
blksz & 0xff, NULL);
if (ret)
return ret;
ret = mmc_io_rw_direct(func->card, 1, 0,
SDIO_FBR_BASE(func->num) + SDIO_FBR_BLKSIZE + 1,
(blksz >> 8) & 0xff, NULL);
if (ret)
return ret;
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)
{
unsigned mval = min(func->card->host->max_seg_size,
func->card->host->max_blk_size);
if (mmc_blksz_for_byte_mode(func->card))
mval = min(mval, func->cur_blksize);
else
mval = min(mval, func->max_blksize);
return min(mval, 512u); /* maximum size for byte mode */
}
/**
* sdio_align_size - pads a transfer size to a more optimal value
* @func: SDIO function
* @sz: original transfer size
*
* Pads the original data size with a number of extra bytes in
* order to avoid controller bugs and/or performance hits
* (e.g. some controllers revert to PIO for certain sizes).
*
* If possible, it will also adjust the size so that it can be
* handled in just a single request.
*
* Returns the improved size, which might be unmodified.
*/
unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz)
{
unsigned int orig_sz;
unsigned int blk_sz, byte_sz;
unsigned chunk_sz;
orig_sz = sz;
/*
* Do a first check with the controller, in case it
* wants to increase the size up to a point where it
* might need more than one block.
*/
sz = mmc_align_data_size(func->card, sz);
/*
* If we can still do this with just a byte transfer, then
* we're done.
*/
if (sz <= sdio_max_byte_size(func))
return sz;
if (func->card->cccr.multi_block) {
/*
* Check if the transfer is already block aligned
*/
if ((sz % func->cur_blksize) == 0)
return sz;
/*
* Realign it so that it can be done with one request,
* and recheck if the controller still likes it.
*/
blk_sz = ((sz + func->cur_blksize - 1) /
func->cur_blksize) * func->cur_blksize;
blk_sz = mmc_align_data_size(func->card, blk_sz);
/*
* This value is only good if it is still just
* one request.
*/
if ((blk_sz % func->cur_blksize) == 0)
return blk_sz;
/*
* We failed to do one request, but at least try to
* pad the remainder properly.
*/
byte_sz = mmc_align_data_size(func->card,
sz % func->cur_blksize);
if (byte_sz <= sdio_max_byte_size(func)) {
blk_sz = sz / func->cur_blksize;
return blk_sz * func->cur_blksize + byte_sz;
}
} else {
/*
* We need multiple requests, so first check that the
* controller can handle the chunk size;
*/
chunk_sz = mmc_align_data_size(func->card,
sdio_max_byte_size(func));
if (chunk_sz == sdio_max_byte_size(func)) {
/*
* Fix up the size of the remainder (if any)
*/
byte_sz = orig_sz % chunk_sz;
if (byte_sz) {
byte_sz = mmc_align_data_size(func->card,
byte_sz);
}
return (orig_sz / chunk_sz) * chunk_sz + byte_sz;
}
}
/*
* The controller is simply incapable of transferring the size
* we want in decent manner, so just return the original size.
*/
return orig_sz;
}
EXPORT_SYMBOL_GPL(sdio_align_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 && (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. */
max_blocks = min(func->card->host->max_blk_count,
func->card->host->max_seg_size / func->cur_blksize);
max_blocks = min(max_blocks, 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 = min(remainder, sdio_max_byte_size(func));
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
* @addr: address to read
* @err_ret: optional status value from transfer
*
* Reads a single byte from the address space of a given SDIO
* function. If there is a problem reading the address, 0xff
* is returned and @err_ret will contain the error code.
*/
u8 sdio_readb(struct sdio_func *func, unsigned int addr, int *err_ret)
{
int ret;
u8 val;
BUG_ON(!func);
if (err_ret)
*err_ret = 0;
ret = mmc_io_rw_direct(func->card, 0, func->num, addr, 0, &val);
if (ret) {
if (err_ret)
*err_ret = ret;
return 0xFF;
}
return val;
}
EXPORT_SYMBOL_GPL(sdio_readb);
/**
* sdio_readb_ext - read a single byte from a SDIO function
* @func: SDIO function to access
* @addr: address to read
* @err_ret: optional status value from transfer
* @in: value to add to argument
*
* Reads a single byte from the address space of a given SDIO
* function. If there is a problem reading the address, 0xff
* is returned and @err_ret will contain the error code.
*/
unsigned char sdio_readb_ext(struct sdio_func *func, unsigned int addr,
int *err_ret, unsigned in)
{
int ret;
unsigned char val;
BUG_ON(!func);
if (err_ret)
*err_ret = 0;
ret = mmc_io_rw_direct(func->card, 0, func->num, addr, (u8)in, &val);
if (ret) {
if (err_ret)
*err_ret = ret;
return 0xFF;
}
return val;
}
EXPORT_SYMBOL_GPL(sdio_readb_ext);
/**
* sdio_writeb - write a single byte to a SDIO function
* @func: SDIO function to access
* @b: byte to write
* @addr: address to write to
* @err_ret: optional status value from transfer
*
* Writes a single byte to the address space of a given SDIO
* function. @err_ret will contain the status of the actual
* transfer.
*/
void sdio_writeb(struct sdio_func *func, u8 b, unsigned int addr, int *err_ret)
{
int ret;
BUG_ON(!func);
ret = mmc_io_rw_direct(func->card, 1, func->num, addr, b, NULL);
if (err_ret)
*err_ret = ret;
}
EXPORT_SYMBOL_GPL(sdio_writeb);
/**
* sdio_writeb_readb - write and read a byte from SDIO function
* @func: SDIO function to access
* @write_byte: byte to write
* @addr: address to write to
* @err_ret: optional status value from transfer
*
* Performs a RAW (Read after Write) operation as defined by SDIO spec -
* single byte is written to address space of a given SDIO function and
* response is read back from the same address, both using single request.
* If there is a problem with the operation, 0xff is returned and
* @err_ret will contain the error code.
*/
u8 sdio_writeb_readb(struct sdio_func *func, u8 write_byte,
unsigned int addr, int *err_ret)
{
int ret;
u8 val;
ret = mmc_io_rw_direct(func->card, 1, func->num, addr,
write_byte, &val);
if (err_ret)
*err_ret = ret;
if (ret)
val = 0xff;
return val;
}
EXPORT_SYMBOL_GPL(sdio_writeb_readb);
/**
* sdio_memcpy_fromio - read a chunk of memory from a SDIO function
* @func: SDIO function to access
* @dst: buffer to store the data
* @addr: address to begin reading from
* @count: number of bytes to read
*
* 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 sdio_io_rw_ext_helper(func, 0, addr, 1, dst, count);
}
EXPORT_SYMBOL_GPL(sdio_memcpy_fromio);
/**
* sdio_memcpy_toio - write a chunk of memory to a SDIO function
* @func: SDIO function to access
* @addr: address to start writing to
* @src: buffer that contains the data to write
* @count: number of bytes to write
*
* 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 sdio_io_rw_ext_helper(func, 1, addr, 1, src, count);
}
EXPORT_SYMBOL_GPL(sdio_memcpy_toio);
/**
* sdio_readsb - read from a FIFO on a SDIO function
* @func: SDIO function to access
* @dst: buffer to store the data
* @addr: address of (single byte) FIFO
* @count: number of bytes to read
*
* 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 sdio_io_rw_ext_helper(func, 0, addr, 0, dst, count);
}
EXPORT_SYMBOL_GPL(sdio_readsb);
/**
* sdio_writesb - write to a FIFO of a SDIO function
* @func: SDIO function to access
* @addr: address of (single byte) FIFO
* @src: buffer that contains the data to write
* @count: number of bytes to write
*
* 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 sdio_io_rw_ext_helper(func, 1, addr, 0, src, count);
}
EXPORT_SYMBOL_GPL(sdio_writesb);
/**
* sdio_readw - read a 16 bit integer from a SDIO function
* @func: SDIO function to access
* @addr: address to read
* @err_ret: optional status value from transfer
*
* Reads a 16 bit integer from the address space of a given SDIO
* function. If there is a problem reading the address, 0xffff
* is returned and @err_ret will contain the error code.
*/
u16 sdio_readw(struct sdio_func *func, unsigned int addr, int *err_ret)
{
int ret;
if (err_ret)
*err_ret = 0;
ret = sdio_memcpy_fromio(func, func->tmpbuf, addr, 2);
if (ret) {
if (err_ret)
*err_ret = ret;
return 0xFFFF;
}
return le16_to_cpup((__le16 *)func->tmpbuf);
}
EXPORT_SYMBOL_GPL(sdio_readw);
/**
* sdio_writew - write a 16 bit integer to a SDIO function
* @func: SDIO function to access
* @b: integer to write
* @addr: address to write to
* @err_ret: optional status value from transfer
*
* Writes a 16 bit integer to the address space of a given SDIO
* function. @err_ret will contain the status of the actual
* transfer.
*/
void sdio_writew(struct sdio_func *func, u16 b, unsigned int addr, int *err_ret)
{
int ret;
*(__le16 *)func->tmpbuf = cpu_to_le16(b);
ret = sdio_memcpy_toio(func, addr, func->tmpbuf, 2);
if (err_ret)
*err_ret = ret;
}
EXPORT_SYMBOL_GPL(sdio_writew);
/**
* sdio_readl - read a 32 bit integer from a SDIO function
* @func: SDIO function to access
* @addr: address to read
* @err_ret: optional status value from transfer
*
* Reads a 32 bit integer from the address space of a given SDIO
* function. If there is a problem reading the address,
* 0xffffffff is returned and @err_ret will contain the error
* code.
*/
u32 sdio_readl(struct sdio_func *func, unsigned int addr, int *err_ret)
{
int ret;
if (err_ret)
*err_ret = 0;
ret = sdio_memcpy_fromio(func, func->tmpbuf, addr, 4);
if (ret) {
if (err_ret)
*err_ret = ret;
return 0xFFFFFFFF;
}
return le32_to_cpup((__le32 *)func->tmpbuf);
}
EXPORT_SYMBOL_GPL(sdio_readl);
/**
* sdio_writel - write a 32 bit integer to a SDIO function
* @func: SDIO function to access
* @b: integer to write
* @addr: address to write to
* @err_ret: optional status value from transfer
*
* Writes a 32 bit integer to the address space of a given SDIO
* function. @err_ret will contain the status of the actual
* transfer.
*/
void sdio_writel(struct sdio_func *func, u32 b, unsigned int addr, int *err_ret)
{
int ret;
*(__le32 *)func->tmpbuf = cpu_to_le32(b);
ret = sdio_memcpy_toio(func, addr, func->tmpbuf, 4);
if (err_ret)
*err_ret = ret;
}
EXPORT_SYMBOL_GPL(sdio_writel);
/**
* sdio_f0_readb - read a single byte from SDIO function 0
* @func: an SDIO function of the card
* @addr: address to read
* @err_ret: optional status value from transfer
*
* Reads a single byte from the address space of SDIO function 0.
* If there is a problem reading the address, 0xff is returned
* and @err_ret will contain the error code.
*/
unsigned char sdio_f0_readb(struct sdio_func *func, unsigned int addr,
int *err_ret)
{
int ret;
unsigned char val;
BUG_ON(!func);
if (err_ret)
*err_ret = 0;
ret = mmc_io_rw_direct(func->card, 0, 0, addr, 0, &val);
if (ret) {
if (err_ret)
*err_ret = ret;
return 0xFF;
}
return val;
}
EXPORT_SYMBOL_GPL(sdio_f0_readb);
/**
* sdio_f0_writeb - write a single byte to SDIO function 0
* @func: an SDIO function of the card
* @b: byte to write
* @addr: address to write to
* @err_ret: optional status value from transfer
*
* Writes a single byte to the address space of SDIO function 0.
* @err_ret will contain the status of the actual transfer.
*
* Only writes to the vendor specific CCCR registers (0xF0 -
* 0xFF) are permiited; @err_ret will be set to -EINVAL for *
* writes outside this range.
*/
void sdio_f0_writeb(struct sdio_func *func, unsigned char b, unsigned int addr,
int *err_ret)
{
int ret;
BUG_ON(!func);
if ((addr < 0xF0 || addr > 0xFF) && (!mmc_card_lenient_fn0(func->card))) {
if (err_ret)
*err_ret = -EINVAL;
return;
}
ret = mmc_io_rw_direct(func->card, 1, 0, addr, b, NULL);
if (err_ret)
*err_ret = ret;
}
EXPORT_SYMBOL_GPL(sdio_f0_writeb);
/**
* sdio_get_host_pm_caps - get host power management capabilities
* @func: SDIO function attached to host
*
* Returns a capability bitmask corresponding to power management
* features supported by the host controller that the card function
* might rely upon during a system suspend. The host doesn't need
* to be claimed, nor the function active, for this information to be
* obtained.
*/
mmc_pm_flag_t sdio_get_host_pm_caps(struct sdio_func *func)
{
BUG_ON(!func);
BUG_ON(!func->card);
return func->card->host->pm_caps;
}
EXPORT_SYMBOL_GPL(sdio_get_host_pm_caps);
/**
* sdio_set_host_pm_flags - set wanted host power management capabilities
* @func: SDIO function attached to host
*
* Set a capability bitmask corresponding to wanted host controller
* power management features for the upcoming suspend state.
* This must be called, if needed, each time the suspend method of
* the function driver is called, and must contain only bits that
* were returned by sdio_get_host_pm_caps().
* The host doesn't need to be claimed, nor the function active,
* for this information to be set.
*/
int sdio_set_host_pm_flags(struct sdio_func *func, mmc_pm_flag_t flags)
{
struct mmc_host *host;
BUG_ON(!func);
BUG_ON(!func->card);
host = func->card->host;
if (flags & ~host->pm_caps)
return -EINVAL;
/* function suspend methods are serialized, hence no lock needed */
host->pm_flags |= flags;
return 0;
}
EXPORT_SYMBOL_GPL(sdio_set_host_pm_flags);