text: /*
   *  linux/drivers/mmc/sdio.c
   *
   *  Copyright 2006-2007 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/err.h>
  
  #include <linux/mmc/host.h>
  #include <linux/mmc/card.h>
  #include <linux/mmc/sdio.h>
  #include <linux/mmc/sdio_func.h>
  
  #include "core.h"
  #include "bus.h"
  #include "sdio_bus.h"
  #include "mmc_ops.h"
  #include "sd_ops.h"
  #include "sdio_ops.h"
  #include "sdio_cis.h"
  
  static int sdio_read_fbr(struct sdio_func *func)
  {
  	int ret;
  	unsigned char data;
  
  	ret = mmc_io_rw_direct(func->card, 0, 0,
  		SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF, 0, &data);
  	if (ret)
  		goto out;
  
  	data &= 0x0f;
  
  	if (data == 0x0f) {
  		ret = mmc_io_rw_direct(func->card, 0, 0,
  			SDIO_FBR_BASE(func->num) + SDIO_FBR_STD_IF_EXT, 0, &data);
  		if (ret)
  			goto out;
  	}
  
  	func->class = data;
  
  out:
  	return ret;
  }
  
  static int sdio_init_func(struct mmc_card *card, unsigned int fn)
  {
  	int ret;
  	struct sdio_func *func;
  
  	BUG_ON(fn > SDIO_MAX_FUNCS);
  
  	func = sdio_alloc_func(card);
  	if (IS_ERR(func))
  		return PTR_ERR(func);
  
  	func->num = fn;
  
  	ret = sdio_read_fbr(func);
  	if (ret)
  		goto fail;
  
  	ret = sdio_read_func_cis(func);
  	if (ret)
  		goto fail;
  
  	card->sdio_func[fn - 1] = func;
  
  	return 0;
  
  fail:
  	/*
  	 * It is okay to remove the function here even though we hold
  	 * the host lock as we haven't registered the device yet.
  	 */
  	sdio_remove_func(func);
  	return ret;
  }
  
  static int sdio_read_cccr(struct mmc_card *card)
  {
  	int ret;
  	int cccr_vsn;
  	unsigned char data;
  
  	memset(&card->cccr, 0, sizeof(struct sdio_cccr));
  
  	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CCCR, 0, &data);
  	if (ret)
  		goto out;
  
  	cccr_vsn = data & 0x0f;
  
  	if (cccr_vsn > SDIO_CCCR_REV_1_20) {
  		printk(KERN_ERR "%s: unrecognised CCCR structure version %d\n",
  			mmc_hostname(card->host), cccr_vsn);
  		return -EINVAL;
  	}
  
  	card->cccr.sdio_vsn = (data & 0xf0) >> 4;
  
  	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_CAPS, 0, &data);
  	if (ret)
  		goto out;
  
  	if (data & SDIO_CCCR_CAP_SMB)
  		card->cccr.multi_block = 1;
  	if (data & SDIO_CCCR_CAP_LSC)
  		card->cccr.low_speed = 1;
  	if (data & SDIO_CCCR_CAP_4BLS)
  		card->cccr.wide_bus = 1;
  
  	if (cccr_vsn >= SDIO_CCCR_REV_1_10) {
  		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_POWER, 0, &data);
  		if (ret)
  			goto out;
  
  		if (data & SDIO_POWER_SMPC)
  			card->cccr.high_power = 1;
  	}
  
  	if (cccr_vsn >= SDIO_CCCR_REV_1_20) {
  		ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &data);
  		if (ret)
  			goto out;
  
  		if (data & SDIO_SPEED_SHS)
  			card->cccr.high_speed = 1;
  	}
  
  out:
  	return ret;
  }
  
  static int sdio_enable_wide(struct mmc_card *card)
  {
  	int ret;
  	u8 ctrl;
  
  	if (!(card->host->caps & MMC_CAP_4_BIT_DATA))
  		return 0;
  
  	if (card->cccr.low_speed && !card->cccr.wide_bus)
  		return 0;
  
  	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
  	if (ret)
  		return ret;
  
  	ctrl |= SDIO_BUS_WIDTH_4BIT;
  
  	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
  	if (ret)
  		return ret;
  
  	mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
  
  	return 0;
  }
  
  /*
   * If desired, disconnect the pull-up resistor on CD/DAT[3] (pin 1)
   * of the card. This may be required on certain setups of boards,
   * controllers and embedded sdio device which do not need the card's
   * pull-up. As a result, card detection is disabled and power is saved.
   */
  static int sdio_disable_cd(struct mmc_card *card)
  {
  	int ret;
  	u8 ctrl;
  
  	if (!card->cccr.disable_cd)
  		return 0;
  
  	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_IF, 0, &ctrl);
  	if (ret)
  		return ret;
  
  	ctrl |= SDIO_BUS_CD_DISABLE;
  
  	return mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_IF, ctrl, NULL);
  }
  
  /*
   * Test if the card supports high-speed mode and, if so, switch to it.
   */
  static int sdio_enable_hs(struct mmc_card *card)
  {
  	int ret;
  	u8 speed;
  
  	if (!(card->host->caps & MMC_CAP_SD_HIGHSPEED))
  		return 0;
  
  	if (!card->cccr.high_speed)
  		return 0;
  
  	ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
  	if (ret)
  		return ret;
  
  	speed |= SDIO_SPEED_EHS;
  
  	ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
  	if (ret)
  		return ret;
  
  	mmc_card_set_highspeed(card);
  	mmc_set_timing(card->host, MMC_TIMING_SD_HS);
  
  	return 0;
  }
  
  /*
   * Handle the detection and initialisation of a card.
   *
   * In the case of a resume, "oldcard" will contain the card
   * we're trying to reinitialise.
   */
  static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
  			      struct mmc_card *oldcard)
  {
  	struct mmc_card *card;
  	int err;
  
  	BUG_ON(!host);
  	WARN_ON(!host->claimed);
  
  	/*
  	 * Inform the card of the voltage
  	 */
  	err = mmc_send_io_op_cond(host, host->ocr, &ocr);
  	if (err)
  		goto err;
  
  	/*
  	 * For SPI, enable CRC as appropriate.
  	 */
  	if (mmc_host_is_spi(host)) {
  		err = mmc_spi_set_crc(host, use_spi_crc);
  		if (err)
  			goto err;
  	}
  
  	/*
  	 * Allocate card structure.
  	 */
  	card = mmc_alloc_card(host, NULL);
  	if (IS_ERR(card)) {
  		err = PTR_ERR(card);
  		goto err;
  	}
  
  	card->type = MMC_TYPE_SDIO;
  
  	/*
  	 * For native busses:  set card RCA and quit open drain mode.
  	 */
  	if (!mmc_host_is_spi(host)) {
  		err = mmc_send_relative_addr(host, &card->rca);
  		if (err)
  			goto remove;
  
  		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
  	}
  
  	/*
  	 * Select card, as all following commands rely on that.
  	 */
  	if (!mmc_host_is_spi(host)) {
  		err = mmc_select_card(card);
  		if (err)
  			goto remove;
  	}
  
  	/*
  	 * Read the common registers.
  	 */
  	err = sdio_read_cccr(card);
  	if (err)
  		goto remove;
  
  	/*
  	 * Read the common CIS tuples.
  	 */
  	err = sdio_read_common_cis(card);
  	if (err)
  		goto remove;
  
  	if (oldcard) {
  		int same = (card->cis.vendor == oldcard->cis.vendor &&
  			    card->cis.device == oldcard->cis.device);
  		mmc_remove_card(card);
  		if (!same) {
  			err = -ENOENT;
  			goto err;
  		}
  		card = oldcard;
  		return 0;
  	}
  
  	/*
  	 * Switch to high-speed (if supported).
  	 */
  	err = sdio_enable_hs(card);
  	if (err)
  		goto remove;
  
  	/*
  	 * Change to the card's maximum speed.
  	 */
  	if (mmc_card_highspeed(card)) {
  		/*
  		 * The SDIO specification doesn't mention how
  		 * the CIS transfer speed register relates to
  		 * high-speed, but it seems that 50 MHz is
  		 * mandatory.
  		 */
  		mmc_set_clock(host, 50000000);
  	} else {
  		mmc_set_clock(host, card->cis.max_dtr);
  	}
  
  	/*
  	 * Switch to wider bus (if supported).
  	 */
  	err = sdio_enable_wide(card);
  	if (err)
  		goto remove;
  
  	if (!oldcard)
  		host->card = card;
  	return 0;
  
  remove:
  	if (!oldcard)
  		mmc_remove_card(card);
  
  err:
  	return err;
  }
  
  /*
   * Host is being removed. Free up the current card.
   */
  static void mmc_sdio_remove(struct mmc_host *host)
  {
  	int i;
  
  	BUG_ON(!host);
  	BUG_ON(!host->card);
  
  	for (i = 0;i < host->card->sdio_funcs;i++) {
  		if (host->card->sdio_func[i]) {
  			sdio_remove_func(host->card->sdio_func[i]);
  			host->card->sdio_func[i] = NULL;
  		}
  	}
  
  	mmc_remove_card(host->card);
  	host->card = NULL;
  }
  
  /*
   * Card detection callback from host.
   */
  static void mmc_sdio_detect(struct mmc_host *host)
  {
  	int err;
  
  	BUG_ON(!host);
  	BUG_ON(!host->card);
  
  	mmc_claim_host(host);
  
  	/*
  	 * Just check if our card has been removed.
  	 */
  	err = mmc_select_card(host->card);
  
  	mmc_release_host(host);
  
  	if (err) {
  		mmc_sdio_remove(host);
  
  		mmc_claim_host(host);
  		mmc_detach_bus(host);
  		mmc_release_host(host);
  	}
  }
  
  /*
   * SDIO suspend.  We need to suspend all functions separately.
   * Therefore all registered functions must have drivers with suspend
   * and resume methods.  Failing that we simply remove the whole card.
   */
  static int mmc_sdio_suspend(struct mmc_host *host)
  {
  	int i, err = 0;
  
  	for (i = 0; i < host->card->sdio_funcs; i++) {
  		struct sdio_func *func = host->card->sdio_func[i];
  		if (func && sdio_func_present(func) && func->dev.driver) {
  			const struct dev_pm_ops *pmops = func->dev.driver->pm;
  			if (!pmops || !pmops->suspend || !pmops->resume) {
  				/* force removal of entire card in that case */
  				err = -ENOSYS;
  			} else
  				err = pmops->suspend(&func->dev);
  			if (err)
  				break;
  		}
  	}
  	while (err && --i >= 0) {
  		struct sdio_func *func = host->card->sdio_func[i];
  		if (func && sdio_func_present(func) && func->dev.driver) {
  			const struct dev_pm_ops *pmops = func->dev.driver->pm;
  			pmops->resume(&func->dev);
  		}
  	}
  
  	return err;
  }
  
  static int mmc_sdio_resume(struct mmc_host *host)
  {
  	int i, err;
  
  	BUG_ON(!host);
  	BUG_ON(!host->card);
  
  	/* Basic card reinitialization. */
  	mmc_claim_host(host);
  	err = mmc_sdio_init_card(host, host->ocr, host->card);
  	mmc_release_host(host);
  
  	/*
  	 * If the card looked to be the same as before suspending, then
  	 * we proceed to resume all card functions.  If one of them returns
  	 * an error then we simply return that error to the core and the
  	 * card will be redetected as new.  It is the responsibility of
  	 * the function driver to perform further tests with the extra
  	 * knowledge it has of the card to confirm the card is indeed the
  	 * same as before suspending (same MAC address for network cards,
  	 * etc.) and return an error otherwise.
  	 */
  	for (i = 0; !err && i < host->card->sdio_funcs; i++) {
  		struct sdio_func *func = host->card->sdio_func[i];
  		if (func && sdio_func_present(func) && func->dev.driver) {
  			const struct dev_pm_ops *pmops = func->dev.driver->pm;
  			err = pmops->resume(&func->dev);
  		}
  	}
  
  	return err;
  }
  
  static const struct mmc_bus_ops mmc_sdio_ops = {
  	.remove = mmc_sdio_remove,
  	.detect = mmc_sdio_detect,
  	.suspend = mmc_sdio_suspend,
  	.resume = mmc_sdio_resume,
  };
  
  
  /*
   * Starting point for SDIO card init.
   */
  int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
  {
  	int err;
  	int i, funcs;
  	struct mmc_card *card;
  
  	BUG_ON(!host);
  	WARN_ON(!host->claimed);
  
  	mmc_attach_bus(host, &mmc_sdio_ops);
  
  	/*
  	 * Sanity check the voltages that the card claims to
  	 * support.
  	 */
  	if (ocr & 0x7F) {
  		printk(KERN_WARNING "%s: card claims to support voltages "
  		       "below the defined range. These will be ignored.\n",
  		       mmc_hostname(host));
  		ocr &= ~0x7F;
  	}
  
  	host->ocr = mmc_select_voltage(host, ocr);
  
  	/*
  	 * Can we support the voltage(s) of the card(s)?
  	 */
  	if (!host->ocr) {
  		err = -EINVAL;
  		goto err;
  	}
  
  	/*
  	 * Detect and init the card.
  	 */
  	err = mmc_sdio_init_card(host, host->ocr, NULL);
  	if (err)
  		goto err;
  	card = host->card;
  
  	/*
  	 * The number of functions on the card is encoded inside
  	 * the ocr.
  	 */
  	card->sdio_funcs = funcs = (ocr & 0x70000000) >> 28;
  
  	/*
  	 * If needed, disconnect card detection pull-up resistor.
  	 */
  	err = sdio_disable_cd(card);
  	if (err)
  		goto remove;
  
  	/*
  	 * Initialize (but don't add) all present functions.
  	 */
  	for (i = 0;i < funcs;i++) {
  		err = sdio_init_func(host->card, i + 1);
  		if (err)
  			goto remove;
  	}
  
  	mmc_release_host(host);
  
  	/*
  	 * First add the card to the driver model...
  	 */
  	err = mmc_add_card(host->card);
  	if (err)
  		goto remove_added;
  
  	/*
  	 * ...then the SDIO functions.
  	 */
  	for (i = 0;i < funcs;i++) {
  		err = sdio_add_func(host->card->sdio_func[i]);
  		if (err)
  			goto remove_added;
  	}
  
  	return 0;
  
  
  remove_added:
  	/* Remove without lock if the device has been added. */
  	mmc_sdio_remove(host);
  	mmc_claim_host(host);
  remove:
  	/* And with lock if it hasn't been added. */
  	if (host->card)
  		mmc_sdio_remove(host);
  err:
  	mmc_detach_bus(host);
  	mmc_release_host(host);
  
  	printk(KERN_ERR "%s: error %d whilst initialising SDIO card\n",
  		mmc_hostname(host), err);
  
  	return err;
  }
  
  