On Mon, 04 Nov 2019, Rajat Jain <rajatja@xxxxxxxxxx> wrote: > Lookup and attach ACPI nodes for intel connectors. The lookup is done > in compliance with ACPI Spec 6.3 > https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf > (Ref: Pages 1119 - 1123). > > This can be useful for any connector specific platform properties. (This > will be used for privacy screen in next patch). > > Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx> > Change-Id: I798e70714a4402554c8cd2a8e58268353f75814f > --- > v2: formed by splitting the original patch into ACPI lookup, and privacy > screen property. Also move it into i915 now that I found existing code > in i915 that can be re-used. > > drivers/gpu/drm/i915/display/intel_acpi.c | 50 +++++++++++++++++++ > drivers/gpu/drm/i915/display/intel_acpi.h | 4 +- > .../drm/i915/display/intel_display_types.h | 3 ++ > drivers/gpu/drm/i915/display/intel_dp.c | 4 ++ > 4 files changed, 60 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_acpi.c b/drivers/gpu/drm/i915/display/intel_acpi.c > index 748d9b3125dd..0c10516430b1 100644 > --- a/drivers/gpu/drm/i915/display/intel_acpi.c > +++ b/drivers/gpu/drm/i915/display/intel_acpi.c > @@ -243,3 +243,53 @@ void intel_populate_acpi_ids_for_all_connectors(struct drm_device *drm_dev) > } > drm_connector_list_iter_end(&conn_iter); > } > + > +/* > + * Ref: ACPI Spec 6.3 > + * https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf > + * Pages 1119 - 1123 describe, what I believe, a standard way of > + * identifying / addressing "display panels" in the ACPI. It provides > + * a way for the ACPI to define devices for the display panels attached > + * to the system. It thus provides a way for the BIOS to export any panel > + * specific properties to the system via ACPI (like device trees). > + * > + * The following functions looks up the ACPI node for a connector and returns > + * it. Technically it is independent from the i915 code, and > + * ideally may be called for all connectors. It is generally a good idea to > + * be able to attach an ACPI node to describe anything if needed. (This can > + * help in future for other panel specific features maybe). However, it > + * needs an acpi device ID which is build using an index within a particular > + * type of port (Ref to the pages of spec mentioned above, and to code in > + * intel_populate_acpi_ids_for_all_connectors()). This device index > + * unfortunately is not available in DRM code, so currently its call is > + * originated from i915 driver. If in future this is useful for other drivers > + * and we can find a generic way of getting a device index, we should move this > + * function to drm code, maybe. > + */ > +void intel_connector_lookup_acpi_node(struct intel_connector *intel_connector) Nitpick, I'd expect a "lookup" function to return whatever it is looking up, not modify its argument. > +{ > + struct drm_device *drm_dev = intel_connector->base.dev; > + struct device *dev = &drm_dev->pdev->dev; > + struct acpi_device *conn_dev; > + u64 conn_addr; > + > + /* > + * Repopulate ACPI IDs for all connectors is needed because the display > + * index may have changed as a result of hotplugging and unplugging > + * connectors > + */ I think that can only be true for DP MST. For everything else, I don't think so. Anyway, why are we doing it here then, depending on whether someone calls this function or not? If it matters, we should be doing this whenever there's a chance they've changed, right? > + intel_populate_acpi_ids_for_all_connectors(drm_dev); > + > + /* Build the _ADR to look for */ > + conn_addr = intel_connector->acpi_device_id; > + conn_addr |= ACPI_DEVICE_ID_SCHEME; > + conn_addr |= ACPI_BIOS_CAN_DETECT; > + > + DRM_DEV_INFO(dev, "Looking for connector ACPI node at _ADR=%llX\n", > + conn_addr); > + > + /* Look up the connector device, under the PCI device */ > + conn_dev = acpi_find_child_device(ACPI_COMPANION(dev), conn_addr, > + false); > + intel_connector->acpi_handle = conn_dev ? conn_dev->handle : NULL; Why don't we do this as part of intel_populate_acpi_ids_for_all_connectors() or whatever it'll be called? > +} > diff --git a/drivers/gpu/drm/i915/display/intel_acpi.h b/drivers/gpu/drm/i915/display/intel_acpi.h > index 8f6d850df6fa..61a4392fac4a 100644 > --- a/drivers/gpu/drm/i915/display/intel_acpi.h > +++ b/drivers/gpu/drm/i915/display/intel_acpi.h > @@ -9,14 +9,16 @@ > #include "intel_display_types.h" > > #ifdef CONFIG_ACPI > +void intel_connector_lookup_acpi_node(struct intel_connector *connector); > void intel_register_dsm_handler(void); > void intel_unregister_dsm_handler(void); > void intel_populate_acpi_ids_for_all_connectors(struct drm_device *drm_dev); > #else > +static inline void > +intel_connector_lookup_acpi_node(struct intel_connector *connector) { return; } > static inline void intel_register_dsm_handler(void) { return; } > static inline void intel_unregister_dsm_handler(void) { return; } > static inline void > -static inline void Whoops. > intel_populate_acpi_ids_for_all_connectors(struct drm_device *drm_dev) { } > #endif /* CONFIG_ACPI */ > > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h > index 449abaea619f..c2706afc069b 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_types.h > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h > @@ -400,6 +400,9 @@ struct intel_connector { > /* ACPI device id for ACPI and driver cooperation */ > u32 acpi_device_id; > > + /* ACPI handle corresponding to this connector display, if found */ > + void *acpi_handle; > + > /* Reads out the current hw, returning true if the connector is enabled > * and active (i.e. dpms ON state). */ > bool (*get_hw_state)(struct intel_connector *); > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c > index f865615172a5..4fac408a4299 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp.c > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > @@ -45,6 +45,7 @@ > #include "i915_debugfs.h" > #include "i915_drv.h" > #include "i915_trace.h" > +#include "intel_acpi.h" > #include "intel_atomic.h" > #include "intel_audio.h" > #include "intel_connector.h" > @@ -6333,6 +6334,7 @@ intel_dp_add_properties(struct intel_dp *intel_dp, struct drm_connector *connect > { > struct drm_i915_private *dev_priv = to_i915(connector->dev); > enum port port = dp_to_dig_port(intel_dp)->base.port; > + struct intel_connector *intel_connector = to_intel_connector(connector); > > if (!IS_G4X(dev_priv) && port != PORT_A) > intel_attach_force_audio_property(connector); > @@ -6354,6 +6356,8 @@ intel_dp_add_properties(struct intel_dp *intel_dp, struct drm_connector *connect > > connector->state->scaling_mode = DRM_MODE_SCALE_ASPECT; > > + /* Lookup the ACPI node corresponding to the connector */ > + intel_connector_lookup_acpi_node(intel_connector); This is an odd place to do this, isn't it? It's only called once, but you say the acpi id may change at hotplug. BR, Jani. > } > } -- Jani Nikula, Intel Open Source Graphics Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
