diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt
index 68ef48839c0484db0dea98da2b419eb4f94b28bf..9f8740ca3f3bc514d9f5426168eb5b2273b96d42 100644
--- a/Documentation/filesystems/sysfs-pci.txt
+++ b/Documentation/filesystems/sysfs-pci.txt
@@ -9,6 +9,7 @@ that support it. For example, a given bus might look like this:
| |-- class
| |-- config
| |-- device
+ | |-- enable
| |-- irq
| |-- local_cpus
| |-- resource
@@ -32,6 +33,7 @@ files, each with their own function.
class PCI class (ascii, ro)
config PCI config space (binary, rw)
device PCI device (ascii, ro)
+ enable Whether the device is enabled (ascii, rw)
irq IRQ number (ascii, ro)
local_cpus nearby CPU mask (cpumask, ro)
resource PCI resource host addresses (ascii, ro)
@@ -57,10 +59,19 @@ used to do actual device programming from userspace. Note that some platforms
don't support mmapping of certain resources, so be sure to check the return
value from any attempted mmap.
+The 'enable' file provides a counter that indicates how many times the device
+has been enabled. If the 'enable' file currently returns '4', and a '1' is
+echoed into it, it will then return '5'. Echoing a '0' into it will decrease
+the count. Even when it returns to 0, though, some of the initialisation
+may not be reversed.
+
The 'rom' file is special in that it provides read-only access to the device's
ROM file, if available. It's disabled by default, however, so applications
should write the string "1" to the file to enable it before attempting a read
-call, and disable it following the access by writing "0" to the file.
+call, and disable it following the access by writing "0" to the file. Note
+that the device must be enabled for a rom read to return data succesfully.
+In the event a driver is not bound to the device, it can be enabled using the
+'enable' file, documented above.
Accessing legacy resources through sysfs
----------------------------------------
diff --git a/arch/ia64/sn/kernel/io_acpi_init.c b/arch/ia64/sn/kernel/io_acpi_init.c
index c5a214026a775c5d82e27fddd1c85cad2d883598..d0223abbbbd4c464df26e0aed6823de0b827944f 100644
--- a/arch/ia64/sn/kernel/io_acpi_init.c
+++ b/arch/ia64/sn/kernel/io_acpi_init.c
@@ -443,7 +443,7 @@ sn_acpi_slot_fixup(struct pci_dev *dev)
size = pci_resource_len(dev, PCI_ROM_RESOURCE);
addr = ioremap(pcidev_info->pdi_pio_mapped_addr[PCI_ROM_RESOURCE],
size);
- image_size = pci_get_rom_size(addr, size);
+ image_size = pci_get_rom_size(dev, addr, size);
dev->resource[PCI_ROM_RESOURCE].start = (unsigned long) addr;
dev->resource[PCI_ROM_RESOURCE].end =
(unsigned long) addr + image_size - 1;
diff --git a/arch/ia64/sn/kernel/io_init.c b/arch/ia64/sn/kernel/io_init.c
index 4e1801bad83a7fdc171a90af0ff3c2df4277f62f..e2eb2da60f963ee3aa7e62c727ef408026b4cd13 100644
--- a/arch/ia64/sn/kernel/io_init.c
+++ b/arch/ia64/sn/kernel/io_init.c
@@ -269,7 +269,7 @@ sn_io_slot_fixup(struct pci_dev *dev)
rom = ioremap(pci_resource_start(dev, PCI_ROM_RESOURCE),
size + 1);
- image_size = pci_get_rom_size(rom, size + 1);
+ image_size = pci_get_rom_size(dev, rom, size + 1);
dev->resource[PCI_ROM_RESOURCE].end =
dev->resource[PCI_ROM_RESOURCE].start +
image_size - 1;
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index db7ec14fa7191828d91f58eb903bfc94cd60ef8c..dfc4e0ddf241b57a93c8e94d3f81a583a772074c 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -768,8 +768,8 @@ pci_read_rom(struct kobject *kobj, struct bin_attribute *bin_attr,
return -EINVAL;
rom = pci_map_rom(pdev, &size); /* size starts out as PCI window size */
- if (!rom)
- return 0;
+ if (!rom || !size)
+ return -EIO;
if (off >= size)
count = 0;
diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c
index 132a78159b60e51bc988dc17acbaec5725e0ed98..29cbe47f219f8c39f2b3f66490a272f339b1f9d5 100644
--- a/drivers/pci/rom.c
+++ b/drivers/pci/rom.c
@@ -63,7 +63,7 @@ void pci_disable_rom(struct pci_dev *pdev)
* The PCI window size could be much larger than the
* actual image size.
*/
-size_t pci_get_rom_size(void __iomem *rom, size_t size)
+size_t pci_get_rom_size(struct pci_dev *pdev, void __iomem *rom, size_t size)
{
void __iomem *image;
int last_image;
@@ -72,8 +72,10 @@ size_t pci_get_rom_size(void __iomem *rom, size_t size)
do {
void __iomem *pds;
/* Standard PCI ROMs start out with these bytes 55 AA */
- if (readb(image) != 0x55)
+ if (readb(image) != 0x55) {
+ dev_err(&pdev->dev, "Invalid ROM contents\n");
break;
+ }
if (readb(image + 1) != 0xAA)
break;
/* get the PCI data structure and check its signature */
@@ -159,7 +161,7 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
* size is much larger than the actual size of the ROM.
* True size is important if the ROM is going to be copied.
*/
- *size = pci_get_rom_size(rom, *size);
+ *size = pci_get_rom_size(pdev, rom, *size);
return rom;
}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 48890cf3f96e562937ded2fc8134f156e9fba60d..7bd624bfdcfd37945e3c59bf2a74f0d2f1dabb21 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -684,7 +684,7 @@ int pci_enable_rom(struct pci_dev *pdev);
void pci_disable_rom(struct pci_dev *pdev);
void __iomem __must_check *pci_map_rom(struct pci_dev *pdev, size_t *size);
void pci_unmap_rom(struct pci_dev *pdev, void __iomem *rom);
-size_t pci_get_rom_size(void __iomem *rom, size_t size);
+size_t pci_get_rom_size(struct pci_dev *pdev, void __iomem *rom, size_t size);
/* Power management related routines */
int pci_save_state(struct pci_dev *dev);