On 3/2/2015 2:27 AM, Suravee Suthikulpanit wrote:
Device drivers typically use ACPI _HIDs/_CIDs listed in struct device_driver acpi_match_table to match devices. However, for generic drivers, we do not want to list _HID for all supported devices. Also, certain classes of devices do not have _CID (e.g. SATA, USB). Instead, we can leverage ACPI _CLS, which specifies PCI-defined class code (i.e. base-class, subclass and programming interface). This patch adds support for matching ACPI devices using the _CLS method.
To support loadable module, current design uses _HID or _CID to match device's modalias. With the new way of matching with _CLS this would requires modification to the current ACPI modalias key to include _CLS. This patch appends PCI-defined class-code to the existing ACPI modalias as following.
acpi:<HID>:<CID1>:<CID2>:..:<CIDn>:<bbsspp>:E.g: # cat /sys/devices/platform/AMDI0600:00/modalias acpi:AMDI0600:010601:
where bb is th base-class code, ss is te sub-class code, and pp is the programming interface code
Since there would not be _HID/_CID in the ACPI matching table of the driver, this patch adds a field to acpi_device_id to specify the matching _CLS.
static const struct acpi_device_id ahci_acpi_match[] = { { "", 0, PCI_CLASS_STORAGE_SATA_AHCI }, {}, };In this case, the corresponded entry in modules.alias file would be:
alias acpi*:010601:* ahci_platformSigned-off-by: Suravee SuthikulpanitSuravee.Suthikulpanit@amd.com
drivers/acpi/acpica/acutils.h | 3 ++ drivers/acpi/acpica/nsxfname.c | 20 +++++++++-- drivers/acpi/acpica/utids.c | 71 +++++++++++++++++++++++++++++++++++++++ drivers/acpi/scan.c | 17 ++++++++-- include/acpi/acnames.h | 1 + include/acpi/actypes.h | 4 ++- include/linux/mod_devicetable.h | 1 + scripts/mod/devicetable-offsets.c | 1 + scripts/mod/file2alias.c | 13 +++++-- 9 files changed, 123 insertions(+), 8 deletions(-)
[....]
diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index b034f10..50d8019 100644 --- a/include/acpi/actypes.h +++ b/include/acpi/actypes.h @@ -1148,7 +1148,7 @@ struct acpi_device_info { u32 name; /* ACPI object Name */ acpi_object_type type; /* ACPI object Type */ u8 param_count; /* If a method, required parameter count */
- u8 valid; /* Indicates which optional fields are valid */
- u16 valid; /* Indicates which optional fields are valid */ u8 flags; /* Miscellaneous info */ u8 highest_dstates[4]; /* _sx_d values: 0xFF indicates not valid */ u8 lowest_dstates[5]; /* _sx_w values: 0xFF indicates not valid */
@@ -1158,6 +1158,7 @@ struct acpi_device_info { struct acpi_pnp_device_id unique_id; /* _UID value */ struct acpi_pnp_device_id subsystem_id; /* _SUB value */ struct acpi_pnp_device_id_list compatible_id_list; /* _CID list <must be last> */
- struct acpi_pnp_device_id cls; /* _CLS value */ };
Please disregard this patch. I found out a mistake on my part here. I have sent out V5 here (https://lkml.org/lkml/2015/3/6/24)
Thank you,
Suravee