mmc: Disabler for Ricoh MMC controller

Thanks to Matt Domsch and Rezwanul Kabir at Dell, we know how to disable the MMC controller on the multi-function Ricoh R5C832. The MMC controller needs to be disabled or it will steal MMC cards from the SD controller where they would otherwise be supported by the Linux SDHCI driver.

@@ -35,6 +35,23 @@
 
 	  If unsure, say N.
 
+config MMC_RICOH_MMC
+	tristate "Ricoh MMC Controller Disabler  (EXPERIMENTAL)"
+	depends on PCI && EXPERIMENTAL && MMC_SDHCI
+	help
+	  This selects the disabler for the Ricoh MMC Controller. This
+	  proprietary controller is unnecessary because the SDHCI driver
+	  supports MMC cards on the SD controller, but if it is not
+	  disabled, it will steal the MMC cards away - rendering them
+	  useless. It is safe to select this driver even if you don't
+	  have a Ricoh based card reader.
+
+
+	  To compile this driver as a module, choose M here:
+	  the module will be called ricoh_mmc.
+
+	  If unsure, say Y.
+
 config MMC_OMAP
 	tristate "TI OMAP Multimedia Card Interface support"
 	depends on ARCH_OMAP

@@ -15,4 +15,5 @@
 obj-$(CONFIG_MMC_OMAP)		+= omap.o
 obj-$(CONFIG_MMC_AT91)		+= at91_mci.o
 obj-$(CONFIG_MMC_TIFM_SD)	+= tifm_sd.o
+obj-$(CONFIG_MMC_RICOH_MMC)	+= ricoh_mmc.o
 

@@ -1485,6 +1485,8 @@
 #define PCI_DEVICE_ID_RICOH_RL5C476	0x0476
 #define PCI_DEVICE_ID_RICOH_RL5C478	0x0478
 #define PCI_DEVICE_ID_RICOH_R5C822	0x0822
+#define PCI_DEVICE_ID_RICOH_R5C832	0x0832
+#define PCI_DEVICE_ID_RICOH_R5C843	0x0843
 
 #define PCI_VENDOR_ID_DLINK		0x1186
 #define PCI_DEVICE_ID_DLINK_DGE510T	0x4c00

Patch looks ok. Please try to sort out that completely disabled controller that was reported first though.

Rgds
Pierre

This remains confusing. I went and investigated and the SD disable bit is 0x20. The one lspci dump from the IFL90 shows that 0x80 is set by default, but setting this on my laptop did not disable the SD controller. I will need to collect more information from owners to find out what's really going on.

Do you want to wait on this before taking this patch?

--phil

Preferably. But if you can't figure it out until it is time to merge things upstream, then I'll go with what we have right now.

Rgds
Pierre

I have not been contacted by anyone with one of those laptops so I haven't been able to find out what's going on.

I'm updating the diff, because I forgot to terminate the pci table, so it didn't add the alias correctly.

--phil