linux/drivers/mmc/core/sdio_io.c
David Vrabel 7806cdb40f sdio: add sdio_f0_readb() and sdio_f0_writeb()
Add sdio_f0_readb() and sdio_f0_writeb() functions to reading and
writing function 0 registers.  Writes outside the vendor specific CCCR
registers (0xF0 - 0xFF) are not permitted.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
2007-09-23 21:24:27 +02:00

548 lines
13 KiB
C

/*
* linux/drivers/mmc/core/sdio_io.c
*
* Copyright 2007 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, &reg);
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;
/*
* FIXME: This should timeout based on information in the CIS,
* but we don't have card to parse that yet.
*/
timeout = jiffies + HZ;
while (1) {
ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IORx, 0, &reg);
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, &reg);
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(min(
func->max_blksize,
func->card->host->max_blk_size),
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);
/* 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
* @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.
*/
unsigned char sdio_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, func->num, addr, 0, &val);
if (ret) {
if (err_ret)
*err_ret = ret;
return 0xFF;
}
return val;
}
EXPORT_SYMBOL_GPL(sdio_readb);
/**
* 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, unsigned char 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_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.
*/
unsigned short 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_cpu(*(u16*)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, unsigned short b, unsigned int addr,
int *err_ret)
{
int ret;
*(u16*)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.
*/
unsigned long 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_cpu(*(u32*)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, unsigned long b, unsigned int addr,
int *err_ret)
{
int ret;
*(u32*)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) {
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);