[RFC] Secure Digital Host Controller PCI class

Pierre Ossman
2005-11-21T11:45:48Z

I'm working on a driver for the Secure Digital Host Controller
interface. This is a generic interface, so it uses a PCI class for
identification instead of vendor/device ids.

The class ID used is 0805 and the programming interface (correct term?)
indicates DMA capabilities. Greg, since you're the PCI maintainer,
perhaps you have the possibility of checking this ID?

The standard also dictates a register at offset 0x40 in PCI space. This
is a one byte register detailing the number of slots on the controller
and the first BAR to use.

The driver isn't ready yet (I'm aiming for 2.6.16) but this is the PCI
related patch I'd like committed further on:

diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -68,6 +68,7 @@
#define PCI_CLASS_SYSTEM_TIMER 0x0802
#define PCI_CLASS_SYSTEM_RTC 0x0803
#define PCI_CLASS_SYSTEM_PCI_HOTPLUG 0x0804
+#define PCI_CLASS_SYSTEM_SDHCI 0x0805
#define PCI_CLASS_SYSTEM_OTHER 0x0880

#define PCI_BASE_CLASS_INPUT 0x09
diff --git a/include/linux/pci_regs.h b/include/linux/pci_regs.h
--- a/include/linux/pci_regs.h
+++ b/include/linux/pci_regs.h
@@ -108,6 +108,9 @@
#define PCI_INTERRUPT_PIN 0x3d /* 8 bits */
#define PCI_MIN_GNT 0x3e /* 8 bits */
#define PCI_MAX_LAT 0x3f /* 8 bits */
+#define PCI_SLOT_INFO 0x40 /* 8 bits */
+#define PCI_SLOT_INFO_SLOTS(x) ((x >> 4) & 7)
+#define PCI_SLOT_INFO_FIRST_BAR_MASK 0x07

/* Header type 1 (PCI-to-PCI bridges) */
#define PCI_PRIMARY_BUS 0x18 /* Primary bus number */