Subject: Re: linux-next: Tree for June 17 (pci/slot)

From: Alex Chiang <[email-masked]>
Date: Wed, 17 Jun 2009 19:03:57 -0600

* Alex Chiang <[email-masked]>:
> diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
> index ba6af16..0be4efd 100644
> --- a/drivers/pci/Makefile
> +++ b/drivers/pci/Makefile
> @@ -2,10 +2,11 @@
>  # Makefile for the PCI bus specific drivers.
>  #
>  
> -obj-y		+= access.o bus.o probe.o remove.o pci.o quirks.o slot.o \
> -			pci-driver.o search.o pci-sysfs.o rom.o setup-res.o \
> +obj-y		+= access.o bus.o probe.o remove.o pci.o quirks.o \
> +			pci-driver.o search.o rom.o setup-res.o \
>  			irq.o
>  obj-$(CONFIG_PROC_FS) += proc.o
> +obj-$(CONFIG_SYSFS) += slot.o pci-sysfs.o

Sigh, this won't work because the PCI core blithely assumes we have
sysfs:

drivers/built-in.o: In function `pci_bus_add_device':
/kio/work/achiang/kernels/linux-2.6/drivers/pci/bus.c:89: undefined reference to `pci_create_sysfs_dev_files'
drivers/built-in.o: In function `pci_stop_dev':
/kio/work/achiang/kernels/linux-2.6/drivers/pci/remove.c:24: undefined reference to `pci_remove_sysfs_dev_files'

So, here is v3 that actually does build with !CONFIG_SYSFS. It
touches a bit more now, but I believe it is still appropriate
because neither pci_slot.ko nor any of the drivers in
drivers/pci/hotplug/ are useful without sysfs.

From: Alex Chiang <[email-masked]>

PCI: drivers/pci/slot.c should depend on CONFIG_SYSFS

There is no way to interact with a physical PCI slot without
sysfs, so encode the dependency and prevent this build error:

	drivers/pci/slot.c: In function 'pci_hp_create_module_link':
	drivers/pci/slot.c:327: error: 'module_kset' undeclared

This patch _should_ make pci-sysfs.o depend on CONFIG_SYSFS too,
but we cannot (yet) because the PCI core merrily assumes the
existence of sysfs:

	drivers/built-in.o: In function `pci_bus_add_device':
	drivers/pci/bus.c:89: undefined reference to `pci_create_sysfs_dev_files'
	drivers/built-in.o: In function `pci_stop_dev':
	drivers/pci/remove.c:24: undefined reference to `pci_remove_sysfs_dev_files'

So do the minimal bit for now and figure out how to untangle it
later.

Cc: Len Brown <[email-masked]>
Reported-by: Stephen Rothwell <[email-masked]>
Fix-suggested-by: Matthew Wilcox <[email-masked]>
Signed-off-by: Alex Chiang <[email-masked]>
---
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 431f8b4..7ec7d88 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -266,6 +266,7 @@ config ACPI_DEBUG_FUNC_TRACE
 
 config ACPI_PCI_SLOT
 	tristate "PCI slot detection driver"
+	depends on SYSFS
 	default n
 	help
 	  This driver creates entries in /sys/bus/pci/slots/ for all PCI
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index ba6af16..ed32f67 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -2,10 +2,11 @@
 # Makefile for the PCI bus specific drivers.
 #
 
-obj-y		+= access.o bus.o probe.o remove.o pci.o quirks.o slot.o \
+obj-y		+= access.o bus.o probe.o remove.o pci.o quirks.o \
 			pci-driver.o search.o pci-sysfs.o rom.o setup-res.o \
 			irq.o
 obj-$(CONFIG_PROC_FS) += proc.o
+obj-$(CONFIG_SYSFS) += slot.o
 
 # Build PCI Express stuff if needed
 obj-$(CONFIG_PCIEPORTBUS) += pcie/
diff --git a/drivers/pci/hotplug/Kconfig b/drivers/pci/hotplug/Kconfig
index 9aa4fe1..522c360 100644
--- a/drivers/pci/hotplug/Kconfig
+++ b/drivers/pci/hotplug/Kconfig
@@ -4,7 +4,7 @@
 
 menuconfig HOTPLUG_PCI
 	tristate "Support for PCI Hotplug"
-	depends on PCI && HOTPLUG
+	depends on PCI && HOTPLUG && SYSFS
 	---help---
 	  Say Y here if you have a motherboard with a PCI Hotplug controller.
 	  This allows you to add and remove PCI cards while the machine is