diff options
author | Suthikulpanit, Suravee <Suravee.Suthikulpanit@amd.com> | 2015-07-07 02:55:20 +0300 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-07-07 02:55:20 +0300 |
commit | 26095a01d359827eeccec5459c28ddd976183179 (patch) | |
tree | 509afc56695ce2fe493cb920958801c314dffcfa /include | |
parent | d770e558e21961ad6cfdf0ff7df0eb5d7d4f0754 (diff) |
ACPI / scan: Add support for ACPI _CLS device matching
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[] = {
{ ACPI_DEVICE_CLASS(PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff) },
{},
};
In this case, the corresponded entry in modules.alias file would be:
alias acpi*:010601:* ahci_platform
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/acpi.h | 14 | ||||
-rw-r--r-- | include/linux/mod_devicetable.h | 2 |
2 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/acpi.h b/include/linux/acpi.h index c471dfc93b71..bdfdb9f65c23 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -58,6 +58,19 @@ static inline acpi_handle acpi_device_handle(struct acpi_device *adev) acpi_fwnode_handle(adev) : NULL) #define ACPI_HANDLE(dev) acpi_device_handle(ACPI_COMPANION(dev)) +/** + * ACPI_DEVICE_CLASS - macro used to describe an ACPI device with + * the PCI-defined class-code information + * + * @_cls : the class, subclass, prog-if triple for this device + * @_msk : the class mask for this device + * + * This macro is used to create a struct acpi_device_id that matches a + * specific PCI class. The .id and .driver_data fields will be left + * initialized with the default value. + */ +#define ACPI_DEVICE_CLASS(_cls, _msk) .cls = (_cls), .cls_msk = (_msk), + static inline bool has_acpi_companion(struct device *dev) { return is_acpi_node(dev->fwnode); @@ -446,6 +459,7 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *); #define ACPI_COMPANION(dev) (NULL) #define ACPI_COMPANION_SET(dev, adev) do { } while (0) #define ACPI_HANDLE(dev) (NULL) +#define ACPI_DEVICE_CLASS(_cls, _msk) .cls = (0), .cls_msk = (0), struct fwnode_handle; diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index 8183d6640ca7..34f25b7bf642 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -189,6 +189,8 @@ struct css_device_id { struct acpi_device_id { __u8 id[ACPI_ID_LEN]; kernel_ulong_t driver_data; + __u32 cls; + __u32 cls_msk; }; #define PNP_ID_LEN 8 |