diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 221127324709..1e12131fb0b3 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -52,6 +52,8 @@ static const unsigned freqs[] = { 400000, 300000, 200000, 100000 }; +static int __mmc_max_reserved_idx = -1; + /* * Enabling software CRCs on the data blocks can be a significant (30%) * performance cost, and for other reasons may not always be desired. @@ -2467,10 +2469,46 @@ void mmc_unregister_pm_notifier(struct mmc_host *host) } #endif +/* + * mmc_first_nonreserved_index() - get the first index that + * is not reserved + */ +int mmc_first_nonreserved_index(void) +{ + return __mmc_max_reserved_idx + 1; +} +EXPORT_SYMBOL(mmc_first_nonreserved_index); + +/* + * mmc_get_reserved_index() - get the index reserved for this host + * Return: The index reserved for this host or negative error value + * if no index is reserved for this host + */ +int mmc_get_reserved_index(struct mmc_host *host) +{ + return of_alias_get_id(host->parent->of_node, "mmc"); +} +EXPORT_SYMBOL(mmc_get_reserved_index); + +static void mmc_of_reserve_idx(void) +{ + int max; + + max = of_alias_max_index("mmc"); + if (max < 0) + return; + + __mmc_max_reserved_idx = max; + pr_debug("MMC: reserving %d slots for of aliases\n", + __mmc_max_reserved_idx + 1); +} + static int __init mmc_init(void) { int ret; + mmc_of_reserve_idx(); + ret = mmc_register_bus(); if (ret) return ret; diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h index 328c78dbee66..70dcd4676d03 100644 --- a/drivers/mmc/core/core.h +++ b/drivers/mmc/core/core.h @@ -76,7 +76,8 @@ int mmc_detect_card_removed(struct mmc_host *host); int mmc_attach_mmc(struct mmc_host *host); int mmc_attach_sd(struct mmc_host *host); int mmc_attach_sdio(struct mmc_host *host); - +int mmc_first_nonreserved_index(void); +int mmc_get_reserved_index(struct mmc_host *host); /* Module parameters */ extern bool use_spi_crc; diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 7efa5c87a6bf..114926d214e1 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -401,6 +401,7 @@ EXPORT_SYMBOL(mmc_of_parse_voltage); struct mmc_host *mmc_alloc_host(int extra, struct device *dev) { int err; + int alias_id; struct mmc_host *host; host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL); @@ -409,8 +410,16 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) /* scanning will be enabled when we're ready */ host->rescan_disable = 1; + host->parent = dev; - err = ida_simple_get(&mmc_host_ida, 0, 0, GFP_KERNEL); + alias_id = mmc_get_reserved_index(host); + if (alias_id >= 0) + err = ida_simple_get(&mmc_host_ida, alias_id, + alias_id + 1, GFP_KERNEL); + else + err = ida_simple_get(&mmc_host_ida, + mmc_first_nonreserved_index(), + 0, GFP_KERNEL); if (err < 0) { kfree(host); return NULL; @@ -420,7 +429,6 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) dev_set_name(&host->class_dev, "mmc%d", host->index); - host->parent = dev; host->class_dev.parent = dev; host->class_dev.class = &mmc_host_class; device_initialize(&host->class_dev); diff --git a/drivers/of/base.c b/drivers/of/base.c index 1d667eb730e1..71b49865b37f 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1981,6 +1981,37 @@ static void of_alias_add(struct alias_prop *ap, struct device_node *np, ap->alias, ap->stem, ap->id, np); } +/* + * of_alias_max_index() - get the maximum index for a given alias stem + * @stem: The alias stem for which the maximum index is searched for + * + * Given an alias stem (the alias without the number) this function + * returns the maximum number for which an alias exists. + * + * Return: The maximum existing alias index or -ENODEV if no alias + * exists for this stem. + */ +int of_alias_max_index(const char *stem) +{ + struct alias_prop *app; + int max = -ENODEV; + + mutex_lock(&of_mutex); + + list_for_each_entry(app, &aliases_lookup, link) { + if (strcmp(app->stem, stem)) + continue; + if (app->id > max) + max = app->id; + } + + mutex_unlock(&of_mutex); + + return max; +} +EXPORT_SYMBOL_GPL(of_alias_max_index); + + /** * of_alias_scan - Scan all properties of the 'aliases' node * diff --git a/include/linux/of.h b/include/linux/of.h index 844f89e1b039..babc3572bbe9 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -391,6 +391,7 @@ extern int of_phandle_iterator_args(struct of_phandle_iterator *it, extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)); extern int of_alias_get_id(struct device_node *np, const char *stem); extern int of_alias_get_highest_id(const char *stem); +extern int of_alias_max_index(const char *stem); extern int of_alias_get_alias_list(const struct of_device_id *matches, const char *stem, unsigned long *bitmap, unsigned int nbits); @@ -911,6 +912,11 @@ static inline int of_alias_get_alias_list(const struct of_device_id *matches, return -ENOSYS; } +static inline int of_alias_max_index(const char *stem) +{ + return -ENODEV; +} + static inline int of_machine_is_compatible(const char *compat) { return 0;