Commit 46f555f2 authored by Pierre Ossman's avatar Pierre Ossman

mmc: add basic SDIO I/O operations

Add command wrappers that simplify register access from SDIO
function drivers.
Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
parent f76c8515
......@@ -9,5 +9,6 @@ endif
obj-$(CONFIG_MMC) += mmc_core.o
mmc_core-y := core.o sysfs.o bus.o host.o \
mmc.o mmc_ops.o sd.o sd_ops.o \
sdio.o sdio_ops.o sdio_bus.o
sdio.o sdio_ops.o sdio_bus.o \
sdio_io.o
/*
* 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_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_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);
......@@ -49,5 +49,17 @@ struct sdio_driver {
extern int sdio_register_driver(struct sdio_driver *);
extern void sdio_unregister_driver(struct sdio_driver *);
/*
* SDIO I/O operations
*/
extern void sdio_claim_host(struct sdio_func *func);
extern void sdio_release_host(struct sdio_func *func);
extern unsigned char sdio_readb(struct sdio_func *func,
unsigned int addr, int *err_ret);
extern void sdio_writeb(struct sdio_func *func, unsigned char b,
unsigned int addr, int *err_ret);
#endif
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