/*

   * (C) Copyright 2007-2008 Semihalf

   *
   * Written by: Rafal Jaworowski <raj@semihalf.com>
   *

   * SPDX-License-Identifier:	GPL-2.0+

   */
  
  #include <config.h>

  #include <common.h>
  #include <api_public.h>

  #if defined(CONFIG_CMD_USB) && defined(CONFIG_USB_STORAGE)
  #include <usb.h>
  #endif

  #define DEBUG
  #undef DEBUG
  
  #ifdef DEBUG
  #define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt, ##args); } while (0)
  #else
  #define debugf(fmt, args...)
  #endif
  
  #define errf(fmt, args...) do { printf("ERROR @ %s(): ", __func__); printf(fmt, ##args); } while (0)
  
  
  #define ENUM_IDE	0
  #define ENUM_USB	1
  #define ENUM_SCSI	2
  #define ENUM_MMC	3

  #define ENUM_SATA	4
  #define ENUM_MAX	5

  
  struct stor_spec {
  	int		max_dev;
  	int		enum_started;
  	int		enum_ended;

  	int		type;	/* "external" type: DT_STOR_{IDE,USB,etc} */

  	char		*name;

  };

  static struct stor_spec specs[ENUM_MAX] = { { 0, 0, 0, 0, NULL }, };

  #ifndef CONFIG_SYS_MMC_MAX_DEVICE
  #define CONFIG_SYS_MMC_MAX_DEVICE	1
  #endif

  
  void dev_stor_init(void)
  {

  #if defined(CONFIG_IDE)

  	specs[ENUM_IDE].max_dev = CONFIG_SYS_IDE_MAXDEVICE;

  	specs[ENUM_IDE].enum_started = 0;
  	specs[ENUM_IDE].enum_ended = 0;
  	specs[ENUM_IDE].type = DEV_TYP_STOR | DT_STOR_IDE;
  	specs[ENUM_IDE].name = "ide";
  #endif

  #if defined(CONFIG_CMD_MMC)

  	specs[ENUM_MMC].max_dev = CONFIG_SYS_MMC_MAX_DEVICE;

  	specs[ENUM_MMC].enum_started = 0;
  	specs[ENUM_MMC].enum_ended = 0;
  	specs[ENUM_MMC].type = DEV_TYP_STOR | DT_STOR_MMC;
  	specs[ENUM_MMC].name = "mmc";
  #endif

  #if defined(CONFIG_SATA)

  	specs[ENUM_SATA].max_dev = CONFIG_SYS_SATA_MAX_DEVICE;

  	specs[ENUM_SATA].enum_started = 0;
  	specs[ENUM_SATA].enum_ended = 0;
  	specs[ENUM_SATA].type = DEV_TYP_STOR | DT_STOR_SATA;
  	specs[ENUM_SATA].name = "sata";

  #endif

  #if defined(CONFIG_SCSI)

  	specs[ENUM_SCSI].max_dev = CONFIG_SYS_SCSI_MAX_DEVICE;

  	specs[ENUM_SCSI].enum_started = 0;
  	specs[ENUM_SCSI].enum_ended = 0;
  	specs[ENUM_SCSI].type = DEV_TYP_STOR | DT_STOR_SCSI;
  	specs[ENUM_SCSI].name = "scsi";
  #endif

  #if defined(CONFIG_CMD_USB) && defined(CONFIG_USB_STORAGE)
  	specs[ENUM_USB].max_dev = USB_MAX_STOR_DEV;
  	specs[ENUM_USB].enum_started = 0;
  	specs[ENUM_USB].enum_ended = 0;
  	specs[ENUM_USB].type = DEV_TYP_STOR | DT_STOR_USB;
  	specs[ENUM_USB].name = "usb";
  #endif

  }
  
  /*
   * Finds next available device in the storage group
   *
   * type:	storage group type - ENUM_IDE, ENUM_SCSI etc.
   *

   * more:	returns 0/1 depending if there are more devices in this group
   *		available (for future iterations)
   *
   * returns:	0/1 depending if device found in this iteration
   */

  static int dev_stor_get(int type, int *more, struct device_info *di)

  {

  	struct blk_desc *dd;

  	int found = 0;
  	int i = 0;

  	/* Wasn't configured for this type, return 0 directly */
  	if (specs[type].name == NULL)
  		return 0;

  	if (di->cookie != NULL) {
  		/* Find the last device we've returned  */
  		for (i = 0; i < specs[type].max_dev; i++) {

  			if (di->cookie ==
  			    (void *)blk_get_dev(specs[type].name, i)) {

  				i += 1;

  				break;
  			}

  		}

  	}

  	for (; i < specs[type].max_dev; i++) {
  		di->cookie = (void *)blk_get_dev(specs[type].name, i);

  
  		if (di->cookie != NULL) {

  			found = 1;
  			break;

  		}

  	}
  
  	if (i == specs[type].max_dev)
  		*more = 0;
  	else
  		*more = 1;

  	if (found) {
  		di->type = specs[type].type;
  
  		dd = (struct blk_desc *)di->cookie;
  		if (dd->type == DEV_TYPE_UNKNOWN) {
  			debugf("device instance exists, but is not active..");
  			found = 0;
  		} else {
  			di->di_stor.block_count = dd->lba;
  			di->di_stor.block_size = dd->blksz;
  		}
  	} else {

  		di->cookie = NULL;

  	}

  
  	return found;
  }

  /* returns: ENUM_IDE, ENUM_USB etc. based on struct blk_desc */

  static int dev_stor_type(struct blk_desc *dd)

  {
  	int i, j;
  
  	for (i = ENUM_IDE; i < ENUM_MAX; i++)
  		for (j = 0; j < specs[i].max_dev; j++)

  			if (dd == blk_get_dev(specs[i].name, j))

  				return i;
  
  	return ENUM_MAX;
  }

  /* returns: 0/1 whether cookie points to some device in this group */

  static int dev_is_stor(int type, struct device_info *di)
  {
  	return (dev_stor_type(di->cookie) == type) ? 1 : 0;
  }
  
  
  static int dev_enum_stor(int type, struct device_info *di)
  {
  	int found = 0, more = 0;
  
  	debugf("called, type %d
  ", type);
  
  	/*
  	 * Formulae for enumerating storage devices:
  	 * 1. if cookie (hint from previous enum call) is NULL we start again
  	 *    with enumeration, so return the first available device, done.
  	 *
  	 * 2. if cookie is not NULL, check if it identifies some device in
  	 *    this group:
  	 *
  	 * 2a. if cookie is a storage device from our group (IDE, USB etc.),
  	 *     return next available (if exists) in this group
  	 *
  	 * 2b. if it isn't device from our group, check if such devices were
  	 *     ever enumerated before:
  	 *     - if not, return the first available device from this group
  	 *     - else return 0
  	 */
  
  	if (di->cookie == NULL) {

  		debugf("group%d - enum restart
  ", type);
  
  		/*
  		 * 1. Enumeration (re-)started: take the first available
  		 * device, if exists
  		 */

  		found = dev_stor_get(type, &more, di);

  		specs[type].enum_started = 1;
  
  	} else if (dev_is_stor(type, di)) {

  		debugf("group%d - enum continued for the next device
  ", type);
  
  		if (specs[type].enum_ended) {
  			debugf("group%d - nothing more to enum!
  ", type);
  			return 0;
  		}
  
  		/* 2a. Attempt to take a next available device in the group */

  		found = dev_stor_get(type, &more, di);

  
  	} else {

  		if (specs[type].enum_ended) {
  			debugf("group %d - already enumerated, skipping
  ", type);
  			return 0;
  		}
  
  		debugf("group%d - first time enum
  ", type);
  
  		if (specs[type].enum_started == 0) {
  			/*
  			 * 2b.  If enumerating devices in this group did not
  			 * happen before, it means the cookie pointed to a

  			 * device from some other group (another storage

  			 * group, or network); in this case try to take the
  			 * first available device from our group
  			 */
  			specs[type].enum_started = 1;
  
  			/*
  			 * Attempt to take the first device in this group:
  			 *'first element' flag is set
  			 */

  			found = dev_stor_get(type, &more, di);

  
  		} else {
  			errf("group%d - out of order iteration
  ", type);
  			found = 0;
  			more = 0;
  		}
  	}
  
  	/*
  	 * If there are no more devices in this group, consider its
  	 * enumeration finished
  	 */
  	specs[type].enum_ended = (!more) ? 1 : 0;
  
  	if (found)
  		debugf("device found, returning cookie 0x%08x
  ",

  		       (u_int32_t)di->cookie);

  	else
  		debugf("no device found
  ");
  
  	return found;
  }
  
  void dev_enum_reset(void)
  {
  	int i;
  
  	for (i = 0; i < ENUM_MAX; i ++) {
  		specs[i].enum_started = 0;
  		specs[i].enum_ended = 0;
  	}
  }
  
  int dev_enum_storage(struct device_info *di)
  {
  	int i;

  	/* check: ide, usb, scsi, mmc */

  	for (i = ENUM_IDE; i < ENUM_MAX; i ++) {
  		if (dev_enum_stor(i, di))
  			return 1;
  	}
  
  	return 0;
  }

  static int dev_stor_is_valid(int type, struct blk_desc *dd)

  {
  	int i;
  
  	for (i = 0; i < specs[type].max_dev; i++)

  		if (dd == blk_get_dev(specs[type].name, i))

  			if (dd->type != DEV_TYPE_UNKNOWN)
  				return 1;
  
  	return 0;
  }
  
  
  int dev_open_stor(void *cookie)
  {
  	int type = dev_stor_type(cookie);
  
  	if (type == ENUM_MAX)
  		return API_ENODEV;

  	if (dev_stor_is_valid(type, (struct blk_desc *)cookie))

  		return 0;
  
  	return API_ENODEV;
  }
  
  
  int dev_close_stor(void *cookie)
  {
  	/*
  	 * Not much to do as we actually do not alter storage devices upon
  	 * close
  	 */
  	return 0;
  }

  lbasize_t dev_read_stor(void *cookie, void *buf, lbasize_t len, lbastart_t start)
  {
  	int type;

  	struct blk_desc *dd = (struct blk_desc *)cookie;

  
  	if ((type = dev_stor_type(dd)) == ENUM_MAX)
  		return 0;
  
  	if (!dev_stor_is_valid(type, dd))
  		return 0;

  #ifdef CONFIG_BLK
  	return blk_dread(dd, start, len, buf);
  #else

  	if ((dd->block_read) == NULL) {

  		debugf("no block_read() for device 0x%08x
  ", cookie);

  		return 0;
  	}

  	return dd->block_read(dd, start, len, buf);

  #endif	/* defined(CONFIG_BLK) */

  }