[RFC PATCH 1/8] mmc: core: remove BUG_ONs from sdio

[Shawn Lin <shawn.lin@rock-chips.com>]

BUG_ONs doesn't help anything except for stop the system from
running. If it occurs, it implies we should deploy proper error
handling for that. So this patch is gonna discard these meaningless
BUG_ONs and deploy error handling if needed.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>

---

 drivers/mmc/core/sdio.c     | 26 ++++++++++++++------------
 drivers/mmc/core/sdio_cis.c |  3 ++-
 drivers/mmc/core/sdio_irq.c | 12 +++++++-----
 3 files changed, 23 insertions(+), 18 deletions(-)

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index bd44ba8..80883c6 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -63,7 +63,8 @@ static int sdio_init_func(struct mmc_card *card, unsigned int fn)
 	int ret;
 	struct sdio_func *func;
 
-	BUG_ON(fn > SDIO_MAX_FUNCS);
+	if (WARN_ON(fn > SDIO_MAX_FUNCS))
+		return -EINVAL;
 
 	func = sdio_alloc_func(card);
 	if (IS_ERR(func))
@@ -555,7 +556,9 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
 	u32 rocr = 0;
 	u32 ocr_card = ocr;
 
-	BUG_ON(!host);
+	if (!host)
+		return -EINVAL;
+
 	WARN_ON(!host->claimed);
 
 	/* to query card if 1.8V signalling is supported */
@@ -791,8 +794,8 @@ static void mmc_sdio_remove(struct mmc_host *host)
 {
 	int i;
 
-	BUG_ON(!host);
-	BUG_ON(!host->card);
+	if (!host)
+		return;
 
 	for (i = 0;i < host->card->sdio_funcs;i++) {
 		if (host->card->sdio_func[i]) {
@@ -820,8 +823,8 @@ static void mmc_sdio_detect(struct mmc_host *host)
 {
 	int err;
 
-	BUG_ON(!host);
-	BUG_ON(!host->card);
+	if (WARN_ON(!host))
+		goto out;
 
 	/* Make sure card is powered before detecting it */
 	if (host->caps & MMC_CAP_POWER_OFF_CARD) {
@@ -916,8 +919,8 @@ static int mmc_sdio_resume(struct mmc_host *host)
 {
 	int err = 0;
 
-	BUG_ON(!host);
-	BUG_ON(!host->card);
+	if (!host)
+		return -EINVAL;
 
 	/* Basic card reinitialization. */
 	mmc_claim_host(host);
@@ -970,9 +973,6 @@ static int mmc_sdio_power_restore(struct mmc_host *host)
 {
 	int ret;
 
-	BUG_ON(!host);
-	BUG_ON(!host->card);
-
 	mmc_claim_host(host);
 
 	/*
@@ -1063,7 +1063,9 @@ int mmc_attach_sdio(struct mmc_host *host)
 	u32 ocr, rocr;
 	struct mmc_card *card;
 
-	BUG_ON(!host);
+	if (!host)
+		return -EINVAL;
+
 	WARN_ON(!host->claimed);
 
 	err = mmc_send_io_op_cond(host, 0, &ocr);
diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index dcb3dee..f8c3728 100644
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -262,7 +262,8 @@ static int sdio_read_cis(struct mmc_card *card, struct sdio_func *func)
 	else
 		prev = &card->tuples;
 
-	BUG_ON(*prev);
+	if (*prev)
+		return -EINVAL;
 
 	do {
 		unsigned char tpl_code, tpl_link;
diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c
index 91bbbfb..f1faf9a 100644
--- a/drivers/mmc/core/sdio_irq.c
+++ b/drivers/mmc/core/sdio_irq.c
@@ -214,7 +214,9 @@ static int sdio_card_irq_put(struct mmc_card *card)
 	struct mmc_host *host = card->host;
 
 	WARN_ON(!host->claimed);
-	BUG_ON(host->sdio_irqs < 1);
+
+	if (host->sdio_irqs < 1)
+		return -EINVAL;
 
 	if (!--host->sdio_irqs) {
 		if (!(host->caps2 & MMC_CAP2_SDIO_IRQ_NOTHREAD)) {
@@ -261,8 +263,8 @@ int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler)
 	int ret;
 	unsigned char reg;
 
-	BUG_ON(!func);
-	BUG_ON(!func->card);
+	if (!func)
+		return -EINVAL;
 
 	pr_debug("SDIO: Enabling IRQ for %s...\n", sdio_func_id(func));
 
@@ -304,8 +306,8 @@ int sdio_release_irq(struct sdio_func *func)
 	int ret;
 	unsigned char reg;
 
-	BUG_ON(!func);
-	BUG_ON(!func->card);
+	if (!func)
+		return -EINVAL;
 
 	pr_debug("SDIO: Disabling IRQ for %s...\n", sdio_func_id(func));
 
-- 
2.3.7