core.c

omap3 linux 2.6 用nocc去除了冗余代码

/*
 *  linux/drivers/mmc/core/core.c
 *
 *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
 *  SD support Copyright (C) 2004 Ian Molton, All Rights Reserved.
 *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
 *  MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/pagemap.h>
#include <linux/err.h>
#include <asm/scatterlist.h>
#include <linux/scatterlist.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sd.h>

#include "core.h"
#include "sysfs.h"

#include "mmc_ops.h"
#include "sd_ops.h"
#include "sdio_ops.h"

extern int mmc_attach_mmc(struct mmc_host *host, u32 ocr);
extern int mmc_attach_sd(struct mmc_host *host, u32 ocr);
extern int mmc_attach_sdio(struct mmc_host *host, u32 ocr);

/**
 *	mmc_request_done - finish processing an MMC request
 *	@host: MMC host which completed request
 *	@mrq: MMC request which request
 *
 *	MMC drivers should call this function when they have completed
 *	their processing of a request.
 */
void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
{
	struct mmc_command *cmd = mrq->cmd;
	int err = cmd->error;

	pr_debug("%s: req done (CMD%u): %d/%d/%d: %08x %08x %08x %08x\n",
		 mmc_hostname(host), cmd->opcode, err,
		 mrq->data ? mrq->data->error : 0,
		 mrq->stop ? mrq->stop->error : 0,
		 cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3]);

	if (err && cmd->retries) {
		cmd->retries--;
		cmd->error = 0;
		host->ops->request(host, mrq);
	} else if (mrq->done) {
		mrq->done(mrq);
	}
}

EXPORT_SYMBOL(mmc_request_done);

/**
 *	mmc_start_request - start a command on a host
 *	@host: MMC host to start command on
 *	@mrq: MMC request to start
 *
 *	Queue a command on the specified host.  We expect the
 *	caller to be holding the host lock with interrupts disabled.
 */
void
mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
{

	pr_debug("%s: starting CMD%u arg %08x flags %08x\n",
		 mmc_hostname(host), mrq->cmd->opcode,
		 mrq->cmd->arg, mrq->cmd->flags);

	WARN_ON(!host->claimed);

	mrq->cmd->error = 0;
	mrq->cmd->mrq = mrq;
	if (mrq->data) {
		BUG_ON(mrq->data->blksz > host->max_blk_size);
		BUG_ON(mrq->data->blocks > host->max_blk_count);
		BUG_ON(mrq->data->blocks * mrq->data->blksz >
			host->max_req_size);


		mrq->cmd->data = mrq->data;
		mrq->data->error = 0;
		mrq->data->mrq = mrq;
		if (mrq->stop) {
			mrq->data->stop = mrq->stop;
			mrq->stop->error = 0;
			mrq->stop->mrq = mrq;
		}
	}
	host->ops->request(host, mrq);
}

EXPORT_SYMBOL(mmc_start_request);

static void mmc_wait_done(struct mmc_request *mrq)
{
	complete(mrq->done_data);
}

int mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
{
	DECLARE_COMPLETION_ONSTACK(complete);

	mrq->done_data = &complete;
	mrq->done = mmc_wait_done;

	mmc_start_request(host, mrq);

	wait_for_completion(&complete);

	return 0;
}

EXPORT_SYMBOL(mmc_wait_for_req);

/**
 *	mmc_wait_for_cmd - start a command and wait for completion
 *	@host: MMC host to start command
 *	@cmd: MMC command to start
 *	@retries: maximum number of retries
 *
 *	Start a new MMC command for a host, and wait for the command
 *	to complete.  Return any error that occurred while the command
 *	was executing.  Do not attempt to parse the response.
 */
int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
{
	struct mmc_request mrq;

	BUG_ON(!host->claimed);

	memset(&mrq, 0, sizeof(struct mmc_request));

	memset(cmd->resp, 0, sizeof(cmd->resp));
	cmd->retries = retries;

	mrq.cmd = cmd;
	cmd->data = NULL;

	mmc_wait_for_req(host, &mrq);

	return cmd->error;
}

EXPORT_SYMBOL(mmc_wait_for_cmd);

/**
 *	mmc_set_data_timeout - set the timeout for a data command
 *	@data: data phase for command
 *	@card: the MMC card associated with the data transfer
 *	@write: flag to differentiate reads from writes
 */
void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card,
			  int write)
{
	unsigned int mult;

	/*
	 * SD cards use a 100 multiplier rather than 10
	 */
	mult = mmc_card_sd(card) ? 100 : 10;

	/*
	 * Scale up the multiplier (and therefore the timeout) by
	 * the r2w factor for writes.
	 */
	if (write)
		mult <<= card->csd.r2w_factor;

	data->timeout_ns = card->csd.tacc_ns * mult;
	data->timeout_clks = card->csd.tacc_clks * mult;

	/*
	 * SD cards also have an upper limit on the timeout.
	 */
	if (mmc_card_sd(card)) {
		unsigned int timeout_us, limit_us;

		timeout_us = data->timeout_ns / 1000;
		timeout_us += data->timeout_clks * 1000 /
			(card->host->ios.clock / 1000);

		if (write)
			limit_us = 250000;
		else
			limit_us = 100000;

		/*
		 * SDHC cards always use these fixed values.
		 */
		if (timeout_us > limit_us || mmc_card_blockaddr(card)) {
			data->timeout_ns = limit_us * 1000;
			data->timeout_clks = 0;
		}
	}
}
EXPORT_SYMBOL(mmc_set_data_timeout);

/**
 *	__mmc_claim_host - exclusively claim a host
 *	@host: mmc host to claim
 *	@card: mmc card to claim host for
 *
 *	Claim a host for a set of operations.  If a valid card
 *	is passed and this wasn't the last card selected, select
 *	the card before returning.
 *
 *	Note: you should use mmc_card_claim_host or mmc_claim_host.
 */
void mmc_claim_host(struct mmc_host *host)
{
	DECLARE_WAITQUEUE(wait, current);
	unsigned long flags;

	add_wait_queue(&host->wq, &wait);
	spin_lock_irqsave(&host->lock, flags);
	while (1) {
		set_current_state(TASK_UNINTERRUPTIBLE);
		if (!host->claimed)
			break;
		spin_unlock_irqrestore(&host->lock, flags);
		schedule();
		spin_lock_irqsave(&host->lock, flags);
	}
	set_current_state(TASK_RUNNING);
	host->claimed = 1;
	spin_unlock_irqrestore(&host->lock, flags);
	remove_wait_queue(&host->wq, &wait);
}

EXPORT_SYMBOL(mmc_claim_host);

/**
 *	mmc_release_host - release a host
 *	@host: mmc host to release
 *
 *	Release a MMC host, allowing others to claim the host
 *	for their operations.
 */
void mmc_release_host(struct mmc_host *host)
{
	unsigned long flags;

	BUG_ON(!host->claimed);

	spin_lock_irqsave(&host->lock, flags);
	host->claimed = 0;
	spin_unlock_irqrestore(&host->lock, flags);

	wake_up(&host->wq);
}

EXPORT_SYMBOL(mmc_release_host);

/*
 * Internal function that does the actual ios call to the host driver,
 * optionally printing some debug output.
 */
static inline void mmc_set_ios(struct mmc_host *host)
{
	struct mmc_ios *ios = &host->ios;

	pr_debug("%s: clock %uHz busmode %u powermode %u cs %u Vdd %u "
		"width %u timing %u\n",
		 mmc_hostname(host), ios->clock, ios->bus_mode,
		 ios->power_mode, ios->chip_select, ios->vdd,
		 ios->bus_width, ios->timing);

	host->ops->set_ios(host, ios);
}

/*
 * Control chip select pin on a host.
 */
void mmc_set_chip_select(struct mmc_host *host, int mode)
{
	host->ios.chip_select = mode;
	mmc_set_ios(host);
}

/*
 * Sets the host clock to the highest possible frequency that
 * is below "hz".
 */
void mmc_set_clock(struct mmc_host *host, unsigned int hz)
{
	WARN_ON(hz < host->f_min);

	if (hz > host->f_max)
		hz = host->f_max;

	host->ios.clock = hz;
	mmc_set_ios(host);
}

/*
 * Change the bus mode (open drain/push-pull) of a host.
 */
void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
{
	host->ios.bus_mode = mode;
	mmc_set_ios(host);
}

/*
 * Change data bus width of a host.
 */
void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
{
	host->ios.bus_width = width;
	mmc_set_ios(host);
}

/*
 * Mask off any voltages we don't support and select
 * the lowest voltage
 */
u32 mmc_select_voltage(struct mmc_host *host, u32 ocr)
{
	int bit;

	ocr &= host->ocr_avail;

	bit = ffs(ocr);
	if (bit) {
		bit -= 1;

		ocr &= 3 << bit;

		host->ios.vdd = bit;
		mmc_set_ios(host);
	} else {
		ocr = 0;
	}

	return ocr;
}

/*
 * Select timing parameters for host.
 */
void mmc_set_timing(struct mmc_host *host, unsigned int timing)
{
	host->ios.timing = timing;