path: root/drivers/pnp/pnpacpi/rsparser.c
diff options
authorBjorn Helgaas <bjorn.helgaas@hp.com>2008-08-22 09:47:17 -0600
committerAndi Kleen <ak@linux.intel.com>2008-08-25 12:04:44 +0200
commitde82ff783bcb2b52353a7c99b4a8524ae739da73 (patch)
tree90f3f930ba351b93df4310c7ab2dab45929c2b06 /drivers/pnp/pnpacpi/rsparser.c
parentb635acec48bcaa9183fcbf4e3955616b0d4119b5 (diff)
PNPACPI: ignore the producer/consumer bit for extended IRQ descriptors
The Extended Interrupt descriptor has a producer/consumer bit, but it's not clear what that would mean, and existing BIOSes use the bit inconsistently. This patch makes Linux PNPACPI ignore the bit. The ACPI spec contains examples of PCI Interrupt Link devices marked as ResourceProducers, but many BIOSes mark them as ResourceConsumers. I also checked with a Windows contact, who said: Windows uses only "resource consumer" when dealing with interrupts. There's no useful way of looking at a resource producer of interrupts. ... NT-based Windows largely infers the producer/consumer stuff from the device type and ignores the bits in the namespace. This was necessary because Windows 98 ignored them and early namespaces contained random junk. The reason I want to change this is because if PNPACPI devices exclude ResourceProducer IRQ resources, we can't write PNP drivers for those devices. For example, on machines such as the the HP rx7620, rx7640, rx8620, rx8640, and Superdome, HPET interrupts are ResourceProducers. The HPET driver currently has to use acpi_bus_register_driver() and do its own _CRS parsing, even though it requires absolutely no ACPI-specific functionality. It would be better if the HPET driver were a PNP driver and took advantage of the _CRS parsing built into PNPACPI. This producer/consumer check was originally added here: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=2b8de5f50e4a302b83ebcd5b0120621336d50bd6 to fix this bug: http://bugzilla.kernel.org/show_bug.cgi?id=6292 However, the bug was related only to memory and I/O port resources, where the distinction is sensible and important to Linux. Given that the distinction is muddled for IRQ resources, I think it was a mistake to add the check there. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
Diffstat (limited to 'drivers/pnp/pnpacpi/rsparser.c')
1 files changed, 0 insertions, 2 deletions
diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c
index d7e9f2152df0..95015cbfd33f 100644
--- a/drivers/pnp/pnpacpi/rsparser.c
+++ b/drivers/pnp/pnpacpi/rsparser.c
@@ -405,8 +405,6 @@ static acpi_status pnpacpi_allocated_resource(struct acpi_resource *res,
extended_irq = &res->data.extended_irq;
- if (extended_irq->producer_consumer == ACPI_PRODUCER)
- return AE_OK;
if (extended_irq->interrupt_count == 0)
pnp_add_irq_resource(dev, 0, IORESOURCE_DISABLED);