RE: [V7 PATCH 1/3] ACPICA: Add ACPI _CLS processing

["Moore, Robert" <robert.moore@intel.com>]

+	cls_objects = obj_desc->package.elements;
+
+	if (obj_desc->common.type == ACPI_TYPE_PACKAGE &&
+	    obj_desc->package.count == 3 &&
+	    cls_objects[0]->common.type == ACPI_TYPE_INTEGER &&
+	    cls_objects[1]->common.type == ACPI_TYPE_INTEGER &&
+	    cls_objects[2]->common.type == ACPI_TYPE_INTEGER) {
+
+		/* Allocate a buffer for the CLS */
+		cls = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_pnp_device_id) +
+					 (acpi_size) 7);

I would like to see an error returned if an object or subobject is of the incorrect type.
Then, the caller knows not to attempt to look at it.


> -----Original Message-----
> From: Suravee Suthikulpanit [mailto:Suravee.Suthikulpanit@amd.com]
> Sent: Thursday, March 26, 2015 12:13 PM
> To: rjw@rjwysocki.net; mika.westerberg@linux.intel.com; Moore, Robert;
> Zheng, Lv; hanjun.guo@linaro.org
> Cc: lenb@kernel.org; hdegoede@redhat.com; tj@kernel.org;
> mjg59@srcf.ucam.org; gregkh@linuxfoundation.org; al.stone@linaro.org;
> graeme.gregory@linaro.org; leo.duran@amd.com; linux-ide@vger.kernel.org;
> linux-acpi@vger.kernel.org; linux-kernel@vger.kernel.org; linaro-
> acpi@lists.linaro.org; Suravee Suthikulpanit
> Subject: [V7 PATCH 1/3] ACPICA: Add ACPI _CLS processing
> 
> ACPI Device configuration often contain _CLS object to suppy PCI-defined
> class code for the device. This patch introduces logic to process the _CLS
> object.
> 
> 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>
> ---
>  drivers/acpi/acpica/acutils.h  |  3 ++
>  drivers/acpi/acpica/nsxfname.c | 21 +++++++++++--
>  drivers/acpi/acpica/utids.c    | 71
> ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 93 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/acpi/acpica/acutils.h b/drivers/acpi/acpica/acutils.h
> index c2f03e8..2aef850 100644
> --- a/drivers/acpi/acpica/acutils.h
> +++ b/drivers/acpi/acpica/acutils.h
> @@ -430,6 +430,9 @@ acpi_status
>  acpi_ut_execute_CID(struct acpi_namespace_node *device_node,
>  		    struct acpi_pnp_device_id_list ** return_cid_list);
> 
> +acpi_status
> +acpi_ut_execute_CLS(struct acpi_namespace_node *device_node,
> +		    struct acpi_pnp_device_id **return_id);
>  /*
>   * utlock - reader/writer locks
>   */
> diff --git a/drivers/acpi/acpica/nsxfname.c
> b/drivers/acpi/acpica/nsxfname.c index d66c326..590ef06 100644
> --- a/drivers/acpi/acpica/nsxfname.c
> +++ b/drivers/acpi/acpica/nsxfname.c
> @@ -276,11 +276,12 @@ acpi_get_object_info(acpi_handle handle,
>  	struct acpi_pnp_device_id *hid = NULL;
>  	struct acpi_pnp_device_id *uid = NULL;
>  	struct acpi_pnp_device_id *sub = NULL;
> +	struct acpi_pnp_device_id *cls = NULL;
>  	char *next_id_string;
>  	acpi_object_type type;
>  	acpi_name name;
>  	u8 param_count = 0;
> -	u8 valid = 0;
> +	u16 valid = 0;
>  	u32 info_size;
>  	u32 i;
>  	acpi_status status;
> @@ -320,7 +321,7 @@ acpi_get_object_info(acpi_handle handle,
>  	if ((type == ACPI_TYPE_DEVICE) || (type == ACPI_TYPE_PROCESSOR)) {
>  		/*
>  		 * Get extra info for ACPI Device/Processor objects only:
> -		 * Run the Device _HID, _UID, _SUB, and _CID methods.
> +		 * Run the Device _HID, _UID, _SUB, _CID and _CLS methods.
>  		 *
>  		 * Note: none of these methods are required, so they may or
> may
>  		 * not be present for this device. The Info->Valid bitfield is
> used @@ -351,6 +352,14 @@ acpi_get_object_info(acpi_handle handle,
>  			valid |= ACPI_VALID_SUB;
>  		}
> 
> +		/* Execute the Device._CLS method */
> +
> +		status = acpi_ut_execute_CLS(node, &cls);
> +		if (ACPI_SUCCESS(status)) {
> +			info_size += cls->length;
> +			valid |= ACPI_VALID_CLS;
> +		}
> +
>  		/* Execute the Device._CID method */
> 
>  		status = acpi_ut_execute_CID(node, &cid_list); @@ -468,6
> +477,11 @@ acpi_get_object_info(acpi_handle handle,
>  							sub, next_id_string);
>  	}
> 
> +	if (cls) {
> +		next_id_string = acpi_ns_copy_device_id(&info->cls,
> +							cls, next_id_string);
> +	}
> +
>  	if (cid_list) {
>  		info->compatible_id_list.count = cid_list->count;
>  		info->compatible_id_list.list_size = cid_list->list_size; @@ -
> 507,6 +521,9 @@ cleanup:
>  	if (sub) {
>  		ACPI_FREE(sub);
>  	}
> +	if (cls) {
> +		ACPI_FREE(cls);
> +	}
>  	if (cid_list) {
>  		ACPI_FREE(cid_list);
>  	}
> diff --git a/drivers/acpi/acpica/utids.c b/drivers/acpi/acpica/utids.c
> index 27431cf..a64b5d1 100644
> --- a/drivers/acpi/acpica/utids.c
> +++ b/drivers/acpi/acpica/utids.c
> @@ -416,3 +416,74 @@ cleanup:
>  	acpi_ut_remove_reference(obj_desc);
>  	return_ACPI_STATUS(status);
>  }
> +
> +/**********************************************************************
> +*********
> + *
> + * FUNCTION:    acpi_ut_execute_CLS
> + *
> + * PARAMETERS:  device_node         - Node for the device
> + *              return_id           - Where the string UID is returned
> + *
> + * RETURN:      Status
> + *
> + * DESCRIPTION: Executes the _CLS control method that returns PCI-defined
> + *              class code of the device. The ACPI spec define _CLS as a
> + *              package with three integers. The returned string has
> format:
> + *
> + *                      "bbsspp"
> + *              where:
> + *                  bb = Base-class code
> + *                  ss = Sub-class code
> + *                  pp = Programming Interface code
> + *
> +
> +***********************************************************************
> +*******/
> +
> +acpi_status
> +acpi_ut_execute_CLS(struct acpi_namespace_node *device_node,
> +		    struct acpi_pnp_device_id **return_id) {
> +	struct acpi_pnp_device_id *cls;
> +	union acpi_operand_object *obj_desc;
> +	union acpi_operand_object **cls_objects;
> +	acpi_status status;
> +
> +	ACPI_FUNCTION_TRACE(ut_execute_CLS);
> +	status = acpi_ut_evaluate_object(device_node, METHOD_NAME__CLS,
> +					 ACPI_BTYPE_PACKAGE, &obj_desc);
> +	if (ACPI_FAILURE(status))
> +		return_ACPI_STATUS(status);
> +
> +	cls_objects = obj_desc->package.elements;
> +
> +	if (obj_desc->common.type == ACPI_TYPE_PACKAGE &&
> +	    obj_desc->package.count == 3 &&
> +	    cls_objects[0]->common.type == ACPI_TYPE_INTEGER &&
> +	    cls_objects[1]->common.type == ACPI_TYPE_INTEGER &&
> +	    cls_objects[2]->common.type == ACPI_TYPE_INTEGER) {
> +
> +		/* Allocate a buffer for the CLS */
> +		cls = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_pnp_device_id) +
> +					 (acpi_size) 7);
> +		if (!cls) {
> +			status = AE_NO_MEMORY;
> +			goto cleanup;
> +		}
> +
> +		cls->string =
> +		    ACPI_ADD_PTR(char, cls, sizeof(struct
> acpi_pnp_device_id));
> +
> +		sprintf(cls->string, "%02x%02x%02x",
> +			(u8)ACPI_TO_INTEGER(cls_objects[0]->integer.value),
> +			(u8)ACPI_TO_INTEGER(cls_objects[1]->integer.value),
> +			(u8)ACPI_TO_INTEGER(cls_objects[2]->integer.value));
> +		cls->length = 7;
> +		*return_id = cls;
> +	}
> +
> +cleanup:
> +
> +	/* On exit, we must delete the return object */
> +
> +	acpi_ut_remove_reference(obj_desc);
> +	return_ACPI_STATUS(status);
> +}
> --
> 2.1.0