redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

mei: hdcp: bind only with i915 on the same PCH 

commit 1e8d19d9b0 upstream.

The mei device and i915 must reside on the same
PCH in order for HDCP to work. Make the component
matching function enforce this requirement.

                   hdcp
                    |
   i915            mei
    |               |
    +----= PCH =----+

Cc: <stable@vger.kernel.org> v5.0+
Cc: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Alexander Usyskin <alexander.usyskin@intel.com>
Link: https://lore.kernel.org/r/20191212084103.2893-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5.4-rM2-2.2.x-imx-squashed
Tomas Winkler 2019-12-12 10:41:03 +02:00 committed by Greg Kroah-Hartman
parent 7d46883724
commit 9272a07978
1 changed files with 30 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
drivers/misc/mei/hdcp/mei_hdcp.c
View File

@ -758,11 +758,38 @@ static const struct component_master_ops mei_component_master_ops = {
.unbind = mei_component_master_unbind,
};
/**
* mei_hdcp_component_match - compare function for matching mei hdcp.
*
* The function checks if the driver is i915, the subcomponent is HDCP
* and the grand parent of hdcp and the parent of i915 are the same
* PCH device.
*
* @dev: master device
* @subcomponent: subcomponent to match (I915_COMPONENT_HDCP)
* @data: compare data (mei hdcp device)
*
* Return:
* * 1 - if components match
* * 0 - otherwise
*/
static int mei_hdcp_component_match(struct device *dev, int subcomponent,
void *data)
{
return !strcmp(dev->driver->name, "i915") &&
subcomponent == I915_COMPONENT_HDCP;
struct device *base = data;
if (strcmp(dev->driver->name, "i915") ||
subcomponent != I915_COMPONENT_HDCP)
return 0;
base = base->parent;
if (!base)
return 0;
base = base->parent;
dev = dev->parent;
return (base && dev && dev == base);
}
static int mei_hdcp_probe(struct mei_cl_device *cldev,
@ -786,7 +813,7 @@ static int mei_hdcp_probe(struct mei_cl_device *cldev,
master_match = NULL;
component_match_add_typed(&cldev->dev, &master_match,
mei_hdcp_component_match, comp_master);
mei_hdcp_component_match, &cldev->dev);
if (IS_ERR_OR_NULL(master_match)) {
ret = -ENOMEM;
goto err_exit;