mmc: add per device quirk placeholder

Some cards have quirks valid for every platforms using current
platform quirk hooks leads to a lot of code and debug duplication.

So we inspire a bit from what exists in PCI subsystem and do our own
per vendorid/deviceid quirk.  We still drop the complexity of the pci
quirk system (with special section tables, and so on).
That can be added later if needed.

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

4 files changed, 66 insertions, 1 deletions

diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
index 86b4791..6395019 100644
--- a/drivers/mmc/core/Makefile
+++ b/drivers/mmc/core/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_MMC)		+= mmc_core.o
 mmc_core-y			:= core.o bus.o host.o \
 				   mmc.o mmc_ops.o sd.o sd_ops.o \
 				   sdio.o sdio_ops.o sdio_bus.o \
-				   sdio_cis.o sdio_io.o sdio_irq.o
+				   sdio_cis.o sdio_io.o sdio_irq.o \
+				   quirks.o
 
 mmc_core-$(CONFIG_DEBUG_FS)	+= debugfs.o
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index ca1fdde..20b1c08 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -61,6 +61,8 @@ int mmc_attach_mmc(struct mmc_host *host);
 int mmc_attach_sd(struct mmc_host *host);
 int mmc_attach_sdio(struct mmc_host *host);
 
+void mmc_fixup_device(struct mmc_card *card);
+
 /* Module parameters */
 extern int use_spi_crc;
 
diff --git a/drivers/mmc/core/quirks.c b/drivers/mmc/core/quirks.c
new file mode 100644
index 0000000..e18cb49
--- /dev/null
+++ b/drivers/mmc/core/quirks.c
@@ -0,0 +1,61 @@
+/*
+ *  This file contains work-arounds for many known sdio hardware
+ *  bugs.
+ *
+ *  Copyright (c) 2011 Pierre Tardy <tardyp@gmail.com>
+ *  Inspired from pci fixup code:
+ *  Copyright (c) 1999 Martin Mares <mj@ucw.cz>
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/mmc/card.h>
+#include <linux/mod_devicetable.h>
+
+/*
+ *  The world is not perfect and supplies us with broken mmc/sdio devices.
+ *  For at least a part of these bugs we need a work-around
+ */
+
+struct mmc_fixup {
+	u16 vendor, device;	/* You can use SDIO_ANY_ID here of course */
+	void (*vendor_fixup)(struct mmc_card *card, int data);
+	int data;
+};
+
+/*
+ * This hook just adds a quirk unconditionnally
+ */
+static void __maybe_unused add_quirk(struct mmc_card *card, int data)
+{
+	card->quirks |= data;
+}
+
+/*
+ * This hook just removes a quirk unconditionnally
+ */
+static void __maybe_unused remove_quirk(struct mmc_card *card, int data)
+{
+	card->quirks &= ~data;
+}
+
+static const struct mmc_fixup mmc_fixup_methods[] = {
+	{ 0 }
+};
+
+void mmc_fixup_device(struct mmc_card *card)
+{
+	const struct mmc_fixup *f;
+
+	for (f = mmc_fixup_methods; f->vendor_fixup; f++) {
+		if ((f->vendor == card->cis.vendor
+		     || f->vendor == (u16) SDIO_ANY_ID) &&
+		    (f->device == card->cis.device
+		     || f->device == (u16) SDIO_ANY_ID)) {
+			dev_dbg(&card->dev, "calling %pF\n", f->vendor_fixup);
+			f->vendor_fixup(card, f->data);
+		}
+	}
+}
+EXPORT_SYMBOL(mmc_fixup_device);
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index ebc62ad..c9fbb77 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -458,6 +458,7 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
 
 		card = oldcard;
 	}
+	mmc_fixup_device(card);
 
 	if (card->type == MMC_TYPE_SD_COMBO) {
 		err = mmc_sd_setup_card(host, card, oldcard != NULL);