Commit deb6596f authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: Refactor slot assignment code 



There are two loops that are almost identical but only with different
checks.  Refactor them with a simple helper, and give a bit more
comments what's doing there.

Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 4c3773ed

sound/core/init.c

+30 −27
Original line number Diff line number Diff line
@@ -131,6 +131,31 @@ static inline int init_info_for_card(struct snd_card *card) 
#define init_info_for_card(card)

#endif



static int check_empty_slot(struct module *module, int slot)

{

	return !slots[slot] || !*slots[slot];

}



/* return an empty slot number (>= 0) found in the given bitmask @mask.

 * @mask == -1 == 0xffffffff means: take any free slot up to 32

 * when no slot is available, return the original @mask as is.

 */

static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),

				 struct module *module)

{

	int slot;



	for (slot = 0; slot < SNDRV_CARDS; slot++) {

		if (slot < 32 && !(mask & (1U << slot)))

			continue;

		if (!test_bit(slot, snd_cards_lock)) {

			if (check(module, slot))

				return slot; /* found */

		}

	}

	return mask; /* unchanged */

}



/**

 *  snd_card_create - create and initialize a soundcard structure

 *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
@@ -152,7 +177,7 @@ int snd_card_create(int idx, const char *xid, 
		    struct snd_card **card_ret)

{

	struct snd_card *card;

	int err, idx2;

	int err;



	if (snd_BUG_ON(!card_ret))

		return -EINVAL;
@@ -167,32 +192,10 @@ int snd_card_create(int idx, const char *xid, 
		strlcpy(card->id, xid, sizeof(card->id));

	err = 0;

	mutex_lock(&snd_card_mutex);

	if (idx < 0) {

		for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++) {

			/* idx == -1 == 0xffff means: take any free slot */

			if (idx2 < 32 && !(idx & (1U << idx2)))

				continue;

			if (!test_bit(idx2, snd_cards_lock)) {

				if (module_slot_match(module, idx2)) {

					idx = idx2;

					break;

				}

			}

		}

	}

	if (idx < 0) {

		for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++) {

			/* idx == -1 == 0xffff means: take any free slot */

			if (idx2 < 32 && !(idx & (1U << idx2)))

				continue;

			if (!test_bit(idx2, snd_cards_lock)) {

				if (!slots[idx2] || !*slots[idx2]) {

					idx = idx2;

					break;

				}

			}

		}

	}

	if (idx < 0) /* first check the matching module-name slot */

		idx = get_slot_from_bitmask(idx, module_slot_match, module);

	if (idx < 0) /* if not matched, assign an empty slot */

		idx = get_slot_from_bitmask(idx, check_empty_slot, module);

	if (idx < 0)

		err = -ENODEV;

	else if (idx < snd_ecards_limit) {