path: root/drivers/pnp/pnpacpi/rsparser.c
diff options
authorBjorn Helgaas <bjorn.helgaas@hp.com>2008-06-09 16:52:06 -0700
committerLen Brown <len.brown@intel.com>2008-06-11 19:13:46 -0400
commit36d872a370d3d10e5a7faa9dcacce744260fb13b (patch)
treee7f8af3c32f22ec88eb8becbb1bd69f1f2470c4a /drivers/pnp/pnpacpi/rsparser.c
parenta993273beae8022390e48fe9205480565ad470ab (diff)
PNPACPI: use _CRS IRQ descriptor length for _SRS
When configuring the resources of an ACPI device, we first evaluate _CRS to get a template of resource descriptors, then fill in the specific resource values we want, and finally evaluate _SRS to actually configure the device. Some resources have optional fields, so the size of encoded descriptors varies depending on the specific values. For example, IRQ descriptors can be either two or three bytes long. The third byte contains triggering information and can be omitted if the IRQ is edge-triggered and active high. The BIOS often assumes that IRQ descriptors in the _SRS buffer use the same format as those in the _CRS buffer, so this patch enforces that constraint. The "Start Dependent Function" descriptor also has an optional byte, but we don't currently encode those descriptors, so I didn't do anything for those. I have tested this patch on a Toshiba Portege 4000. Without the patch, parport_pc claims the parallel port only if I use "pnpacpi=off". This patch makes it work with PNPACPI. This is an extension of a patch by Tom Jaeger: http://bugzilla.kernel.org/show_bug.cgi?id=9487#c42 References: http://bugzilla.kernel.org/show_bug.cgi?id=5832 Enabling ACPI Plug and Play in kernels >2.6.9 kills Parallel support http://bugzilla.kernel.org/show_bug.cgi?id=9487 buggy firmware expects four-byte IRQ resource descriptor (was: Serial port disappears after Suspend on Toshiba R25) http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=1d5b285da1893b90507b081664ac27f1a8a3dc5b related ACPICA fix Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/pnp/pnpacpi/rsparser.c')
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/pnp/pnpacpi/rsparser.c b/drivers/pnp/pnpacpi/rsparser.c
index 8681ff647201..46c791adb894 100644
--- a/drivers/pnp/pnpacpi/rsparser.c
+++ b/drivers/pnp/pnpacpi/rsparser.c
@@ -755,6 +755,9 @@ static acpi_status pnpacpi_type_resources(struct acpi_resource *res, void *data)
if (pnpacpi_supported_resource(res)) {
(*resource)->type = res->type;
(*resource)->length = sizeof(struct acpi_resource);
+ if (res->type == ACPI_RESOURCE_TYPE_IRQ)
+ (*resource)->data.irq.descriptor_length =
+ res->data.irq.descriptor_length;
@@ -810,10 +813,12 @@ static void pnpacpi_encode_irq(struct pnp_dev *dev,
irq->interrupt_count = 1;
irq->interrupts[0] = p->start;
- dev_dbg(&dev->dev, " encode irq %d %s %s %s\n", (int) p->start,
+ dev_dbg(&dev->dev, " encode irq %d %s %s %s (%d-byte descriptor)\n",
+ (int) p->start,
triggering == ACPI_LEVEL_SENSITIVE ? "level" : "edge",
polarity == ACPI_ACTIVE_LOW ? "low" : "high",
- irq->sharable == ACPI_SHARED ? "shared" : "exclusive");
+ irq->sharable == ACPI_SHARED ? "shared" : "exclusive",
+ irq->descriptor_length);
static void pnpacpi_encode_ext_irq(struct pnp_dev *dev,