On Friday, January 24, 2014 08:25:23 AM Bjorn Helgaas wrote:
On Fri, Jan 24, 2014 at 8:36 AM, Rafael J. Wysocki rjw@rjwysocki.net wrote:
On Friday, January 24, 2014 07:54:29 AM Bjorn Helgaas wrote:
On Thu, Jan 23, 2014 at 5:33 PM, Rafael J. Wysocki rjw@rjwysocki.net wrote:
On Thursday, January 23, 2014 11:21:01 AM Bjorn Helgaas wrote:
On Wed, Jan 22, 2014 at 8:42 PM, Yijing Wang wangyijing@huawei.com wrote:
Since acpi_evaluate_object() returns acpi_status and not plain int, ACPI_FAILURE() should be used for checking its return value. Also add some detailed debug info when acpi_evaluate_object() failed.
Reviewed-by: Jani Nikula jani.nikula@intel.com Acked-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Yijing Wang wangyijing@huawei.com
v4->v5: Add some detailed debug info for acpi_evaluate_object() failure suggested by Bjorn. v3->v4: Fix spell error, add Jani Nikula reviewed-by. v2->v3: Fix compile error pointed out by Hanjun. v1->v2: Add CC to related subsystem MAINTAINERS
drivers/gpu/drm/i915/intel_acpi.c | 33 ++++++++++++++++------- drivers/gpu/drm/nouveau/core/subdev/mxm/base.c | 13 ++++++--- drivers/gpu/drm/nouveau/nouveau_acpi.c | 25 +++++++++++------- drivers/pci/pci-label.c | 10 +++++-- 4 files changed, 54 insertions(+), 27 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_acpi.c b/drivers/gpu/drm/i915/intel_acpi.c index dfff090..e7b526b 100644 --- a/drivers/gpu/drm/i915/intel_acpi.c +++ b/drivers/gpu/drm/i915/intel_acpi.c @@ -31,11 +31,13 @@ static const u8 intel_dsm_guid[] = { static int intel_dsm(acpi_handle handle, int func) { struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_object_list input; union acpi_object params[4]; union acpi_object *obj; u32 result;
int ret = 0;
acpi_status status;int ret; input.count = 4; input.pointer = params;@@ -50,10 +52,14 @@ static int intel_dsm(acpi_handle handle, int func) params[3].package.count = 0; params[3].package.elements = NULL;
ret = acpi_evaluate_object(handle, "_DSM", &input, &output);if (ret) {DRM_DEBUG_DRIVER("failed to evaluate _DSM: %d\n", ret);return ret;
status = acpi_evaluate_object(handle, "_DSM", &input, &output);if (ACPI_FAILURE(status)) {acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);DRM_DEBUG_DRIVER("failed to evaluate _DSM for %s, exit status %u\n",(char *)string.pointer, (unsigned int)status);kfree(string.pointer);return -EINVAL;I said "too bad there isn't an *easy* way" to include more information. IMHO this is too ugly and error-prone to use consistently. And if you are going to add more information, why did you only do it for some of the calls and not others?
I considered adding a %p extension to print the pathname; I don't know if that's worthwhile or not. I think it would be ideal if we had a struct device and could use dev_info(), and then a way to connect the struct device with an ACPI path, like maybe a dmesg note when we create the struct device corresponding to an ACPI Device node.
Well, we can generally print something like that from pci_acpi_setup().
What about the below? Wouldn't it generate too much output on some systems?
Yeah, that probably would generate an awful lot of output. I was just hoping to avoid treating ACPI pathnames as first-class objects. What do you think about a %p extension? I played with that once, but I seem to have lost the patch.
Well, it may be worth doing. However, that information is readily available from sysfs anyway, you only need to follow the firmware_node link in the PCI device's sysfs directory and read the path attribute from there. For example, on my system:
$ cat /sys/devices/pci0000:00/0000:00:1c.4/0000:0b:00.0/firmware_node/path _SB_.PCI0.RP05.PXSX
That's perfect. If we had a struct device, we could just use dev_info() for these messages. But I have no idea how hard it would be to get at the struct device.
From the pci_dev side that is trivial: use ACPI_COMPANION(). The other way
around is rather more difficult as browsing a list would be involved.
Rafael