xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

PCI: shpchp: Separate existence of SHPC and permission to use it

Browse Source 
The shpchp driver registers for all PCI bridge devices.  Its probe method
should fail if either (1) the bridge doesn't have an SHPC or (2) the OS
isn't allowed to use it (the platform firmware may be operating the SHPC
itself).

Separate these two tests into:

  - A new shpc_capable() that looks for the SHPC hardware and is applicable
    on all systems (ACPI and non-ACPI), and

  - A simplified acpi_get_hp_hw_control_from_firmware() that we call only
    when we already know an SHPC exists and there may be ACPI methods to
    either request permission to use it (_OSC) or transfer control to the
    OS (OSHP).

acpi_get_hp_hw_control_from_firmware() is implemented when CONFIG_ACPI=y,
but does nothing if the current platform doesn't support ACPI.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
This commit is contained in:
Bjorn Helgaas
2018-06-25 16:49:06 -05:00
committed by Bjorn Helgaas
parent 6f6f42466d
commit b03799b0cb
4 changed files with 42 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/pci.h
View File

@@ -388,6 +388,7 @@ struct pci_dev {
unsigned int is_virtfn:1;
unsigned int reset_fn:1;
unsigned int is_hotplug_bridge:1;
unsigned int shpc_managed:1; /* SHPC owned by shpchp */
unsigned int is_thunderbolt:1; /* Thunderbolt controller */
unsigned int __aer_firmware_first_valid:1;
unsigned int __aer_firmware_first:1;