[v2,2/3] mmc: add MMC_QUIRK_BROKEN_CLK_GATING

Commit Message

Pierre Tardy Feb. 6, 2011, 6:03 p.m. UTC

None

Patch

diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index b3ac6c5..461e6a1 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -160,10 +160,7 @@  static bool mmc_host_may_gate_card(struct mmc_card *card)
 	 * gate the clock, because there is somebody out there that may still
 	 * be using it.
 	 */
-	if (mmc_card_sdio(card))
-		return false;
-
-	return true;
+	return !(card->quirks & MMC_QUIRK_BROKEN_CLK_GATING);
 }
 
 /**
diff --git a/drivers/mmc/core/quirks.c b/drivers/mmc/core/quirks.c
index aa811fc..d004106 100644
--- a/drivers/mmc/core/quirks.c
+++ b/drivers/mmc/core/quirks.c
@@ -40,7 +40,20 @@  static void __maybe_unused remove_quirk(struct mmc_card *card, int data)
 	card->quirks &= ~data;
 }
 
+/*
+ * This hook just adds a quirk for all sdio devices
+ */
+static void add_quirk_for_sdio_devices(struct mmc_card *card, int data)
+{
+	if (mmc_card_sdio(card))
+		card->quirks |= data;
+}
+
 static const struct mmc_fixup mmc_fixup_methods[] = {
+	/* by default sdio devices are considered CLK_GATING broken */
+	/* good cards will be whitelisted as they are tested */
+	{ SDIO_ANY_ID, SDIO_ANY_ID,
+		add_quirk_for_sdio_devices, MMC_QUIRK_BROKEN_CLK_GATING }
 	{ 0 }
 };
 
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index ad74138..adb4888 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -124,6 +124,7 @@  struct mmc_card {
 						/* for byte mode */
 #define MMC_QUIRK_NONSTD_SDIO	(1<<2)		/* non-standard SDIO card attached */
 						/* (missing CIA registers) */
+#define MMC_QUIRK_BROKEN_CLK_GATING (1<<3)	/* clock gating the sdio bus will make card fail */
 
 	unsigned int		erase_size;	/* erase size in sectors */
  	unsigned int		erase_shift;	/* if erase unit is power 2 */