[PATCH v7 4/4] drm/i915: Add support for integrated privacy screen
From: Rajat Jain
Date: Mon Mar 09 2020 - 20:06:37 EST
Add support for an ACPI based integrated privacy screen that is
available on some systems.
Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
---
v7: * Move the privacy-screen property back into drm core.
* Do the actual HW EPS toggling at commit time.
* Provide a sample ACPI node for reference in comments.
v6: Always initialize prop in intel_attach_privacy_screen_property()
v5: fix a cosmetic checkpatch warning
v4: Fix a typo in intel_privacy_screen.h
v3: * Change license to GPL-2.0 OR MIT
* Move privacy screen enum from UAPI to intel_display_types.h
* Rename parameter name and some other minor changes.
v2: Formed by splitting the original patch into multiple patches.
- All code has been moved into i915 now.
- Privacy screen is a i915 property
- Have a local state variable to store the prvacy screen. Don't read
it from hardware.
drivers/gpu/drm/i915/Makefile | 3 +-
drivers/gpu/drm/i915/display/intel_atomic.c | 1 +
drivers/gpu/drm/i915/display/intel_dp.c | 30 ++-
.../drm/i915/display/intel_privacy_screen.c | 175 ++++++++++++++++++
.../drm/i915/display/intel_privacy_screen.h | 27 +++
5 files changed, 234 insertions(+), 2 deletions(-)
create mode 100644 drivers/gpu/drm/i915/display/intel_privacy_screen.c
create mode 100644 drivers/gpu/drm/i915/display/intel_privacy_screen.h
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 9f887a86e555d..da42389107f9c 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -209,7 +209,8 @@ i915-y += \
display/intel_vga.o
i915-$(CONFIG_ACPI) += \
display/intel_acpi.o \
- display/intel_opregion.o
+ display/intel_opregion.o \
+ display/intel_privacy_screen.o
i915-$(CONFIG_DRM_FBDEV_EMULATION) += \
display/intel_fbdev.o
diff --git a/drivers/gpu/drm/i915/display/intel_atomic.c b/drivers/gpu/drm/i915/display/intel_atomic.c
index d043057d2fa03..fc6264b4a7f73 100644
--- a/drivers/gpu/drm/i915/display/intel_atomic.c
+++ b/drivers/gpu/drm/i915/display/intel_atomic.c
@@ -150,6 +150,7 @@ int intel_digital_connector_atomic_check(struct drm_connector *conn,
new_conn_state->base.picture_aspect_ratio != old_conn_state->base.picture_aspect_ratio ||
new_conn_state->base.content_type != old_conn_state->base.content_type ||
new_conn_state->base.scaling_mode != old_conn_state->base.scaling_mode ||
+ new_conn_state->base.privacy_screen_status != old_conn_state->base.privacy_screen_status ||
!blob_equal(new_conn_state->base.hdr_output_metadata,
old_conn_state->base.hdr_output_metadata))
crtc_state->mode_changed = true;
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 41c623b029464..a39b0c420b50a 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -62,6 +62,7 @@
#include "intel_lspcon.h"
#include "intel_lvds.h"
#include "intel_panel.h"
+#include "intel_privacy_screen.h"
#include "intel_psr.h"
#include "intel_sideband.h"
#include "intel_tc.h"
@@ -5886,6 +5887,12 @@ intel_dp_connector_register(struct drm_connector *connector)
dev_priv->acpi_scan_done = true;
}
+ /* Check for integrated Privacy screen support */
+ if (intel_privacy_screen_present(to_intel_connector(connector)))
+ drm_connector_attach_privacy_screen_property(connector);
+ else
+ drm_connector_destroy_privacy_screen_property(connector);
+
DRM_DEBUG_KMS("registering %s bus for %s\n",
intel_dp->aux.name, connector->kdev->kobj.name);
@@ -6881,9 +6888,30 @@ intel_dp_add_properties(struct intel_dp *intel_dp, struct drm_connector *connect
drm_connector_attach_scaling_mode_property(connector, allowed_scalers);
connector->state->scaling_mode = DRM_MODE_SCALE_ASPECT;
+
+ drm_connector_create_privacy_screen_property(connector);
}
}
+static void intel_dp_update_privacy_screen(struct intel_encoder *encoder,
+ const struct intel_crtc_state *crtc_state,
+ const struct drm_connector_state *conn_state)
+{
+ struct drm_connector *connector = conn_state->connector;
+
+ if (connector->privacy_screen_property)
+ intel_privacy_screen_set_val(to_intel_connector(connector),
+ conn_state->privacy_screen_status);
+}
+
+static void intel_dp_update_pipe(struct intel_encoder *encoder,
+ const struct intel_crtc_state *crtc_state,
+ const struct drm_connector_state *conn_state)
+{
+ intel_dp_update_privacy_screen(encoder, crtc_state, conn_state);
+ intel_panel_update_backlight(encoder, crtc_state, conn_state);
+}
+
static void intel_dp_init_panel_power_timestamps(struct intel_dp *intel_dp)
{
intel_dp->panel_power_off_time = ktime_get_boottime();
@@ -7825,7 +7853,7 @@ bool intel_dp_init(struct drm_i915_private *dev_priv,
intel_encoder->compute_config = intel_dp_compute_config;
intel_encoder->get_hw_state = intel_dp_get_hw_state;
intel_encoder->get_config = intel_dp_get_config;
- intel_encoder->update_pipe = intel_panel_update_backlight;
+ intel_encoder->update_pipe = intel_dp_update_pipe;
intel_encoder->suspend = intel_dp_encoder_suspend;
if (IS_CHERRYVIEW(dev_priv)) {
intel_encoder->pre_pll_enable = chv_dp_pre_pll_enable;
diff --git a/drivers/gpu/drm/i915/display/intel_privacy_screen.c b/drivers/gpu/drm/i915/display/intel_privacy_screen.c
new file mode 100644
index 0000000000000..6ff61ddf4c0a4
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_privacy_screen.c
@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/*
+ * Intel ACPI privacy screen code
+ *
+ * Copyright  2020 Google Inc.
+ *
+ * This code can help detect and control an integrated EPS (electronic
+ * privacy screen) via ACPI functions. It expects an ACPI node for the
+ * drm connector device with the following elements:
+ *
+ * UUID should be "c7033113-8720-4ceb-9090-9d52b3e52d73"
+ *
+ * _ADR = ACPI address per Spec (also see intel_acpi_device_id_update())
+ * https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf
+ * Pages 1119 - 1123.
+ *
+ * _DSM method that will perform the following functions according to
+ * Local1 argument passed to it:
+ * - Local1 = 0 (EPS capabilities): Report EPS presence and capabilities.
+ * - Local1 = 1 (EPS State) : _DSM returns 1 if EPS is enabled, 0 otherwise.
+ * - Local1 = 2 (EPS Enable) : _DSM enables EPS
+ * - Local1 = 3 (EPS Disable): _DSM disables EPS
+ *
+ * Here is a sample ACPI node:
+ *
+ * Scope (\_SB.PCI0.GFX0) // Intel graphics device (PCI device)
+ * {
+ * Method (_DOD, 0, NotSerialized) // _DOD: Display Output Devices
+ * {
+ * Return (Package (0x01)
+ * {
+ * 0x80010400
+ * })
+ * }
+ *
+ * Device (LCD)
+ * {
+ * Name (_ADR, 0x80010400) // _ADR: Address
+ * Name (_STA, 0x0F) // _STA: Status
+ *
+ * Method (EPSP, 0, NotSerialized) // EPS Present
+ * {
+ * Return (0x01)
+ * }
+ *
+ * Method (EPSS, 0, NotSerialized) // EPS State
+ * {
+ * Local0 = \_SB.PCI0.GRXS (0xCD)
+ * Return (Local0)
+ * }
+ *
+ * Method (EPSE, 0, NotSerialized) // EPS Enable
+ * {
+ * \_SB.PCI0.STXS (0xCD)
+ * }
+ *
+ * Method (EPSD, 0, NotSerialized) // EPS Disable
+ * {
+ * \_SB.PCI0.CTXS (0xCD)
+ * }
+ *
+ * Method (_DSM, 4, Serialized) // _DSM: Device-Specific Method
+ * {
+ * ToBuffer (Arg0, Local0)
+ * If ((Local0 == ToUUID ("c7033113-8720-4ceb-9090-9d52b3e52d73")))
+ * {
+ * ToInteger (Arg2, Local1)
+ * If ((Local1 == Zero))
+ * {
+ * Local2 = EPSP ()
+ * If ((Local2 == One))
+ * {
+ * Return (Buffer (One)
+ * {
+ * 0x0F
+ * })
+ * }
+ * }
+ *
+ * If ((Local1 == One))
+ * {
+ * Return (EPSS ())
+ * }
+ *
+ * If ((Local1 == 0x02))
+ * {
+ * EPSE ()
+ * }
+ *
+ * If ((Local1 == 0x03))
+ * {
+ * EPSD ()
+ * }
+ *
+ * Return (Buffer (One)
+ * {
+ * 0x00
+ * })
+ * }
+ *
+ * Return (Buffer (One)
+ * {
+ * 0x00
+ * })
+ * }
+ * }
+ * }
+ */
+
+#include <linux/acpi.h>
+
+#include "intel_privacy_screen.h"
+
+#define CONNECTOR_DSM_REVID 1
+
+#define CONNECTOR_DSM_FN_PRIVACY_ENABLE 2
+#define CONNECTOR_DSM_FN_PRIVACY_DISABLE 3
+
+static const guid_t drm_conn_dsm_guid =
+ GUID_INIT(0xC7033113, 0x8720, 0x4CEB,
+ 0x90, 0x90, 0x9D, 0x52, 0xB3, 0xE5, 0x2D, 0x73);
+
+/* Makes _DSM call to set privacy screen status */
+static void acpi_privacy_screen_call_dsm(struct intel_connector *connector,
+ u64 func)
+{
+ union acpi_object *obj;
+ acpi_handle acpi_handle = connector->acpi_handle;
+
+ if (!acpi_handle)
+ return;
+
+ obj = acpi_evaluate_dsm(acpi_handle, &drm_conn_dsm_guid,
+ CONNECTOR_DSM_REVID, func, NULL);
+ if (!obj) {
+ drm_err(connector->base.dev,
+ "failed to evaluate _DSM for fn %llx\n", func);
+ return;
+ }
+
+ ACPI_FREE(obj);
+}
+
+void intel_privacy_screen_set_val(struct intel_connector *connector,
+ enum drm_privacy_screen_status val)
+{
+ if (val == PRIVACY_SCREEN_DISABLED)
+ acpi_privacy_screen_call_dsm(connector,
+ CONNECTOR_DSM_FN_PRIVACY_DISABLE);
+ else if (val == PRIVACY_SCREEN_ENABLED)
+ acpi_privacy_screen_call_dsm(connector,
+ CONNECTOR_DSM_FN_PRIVACY_ENABLE);
+ else
+ drm_err(connector->base.dev,
+ "Cannot set privacy screen to invalid val %u\n", val);
+}
+
+bool intel_privacy_screen_present(struct intel_connector *connector)
+{
+ acpi_handle handle = connector->acpi_handle;
+
+ if (!handle)
+ return false;
+
+ if (!acpi_check_dsm(handle, &drm_conn_dsm_guid,
+ CONNECTOR_DSM_REVID,
+ 1 << CONNECTOR_DSM_FN_PRIVACY_ENABLE |
+ 1 << CONNECTOR_DSM_FN_PRIVACY_DISABLE)) {
+ drm_dbg_kms(connector->base.dev,
+ "ACPI node but no privacy scrn\n");
+ return false;
+ }
+ drm_info(connector->base.dev, "supports privacy screen\n");
+ return true;
+}
diff --git a/drivers/gpu/drm/i915/display/intel_privacy_screen.h b/drivers/gpu/drm/i915/display/intel_privacy_screen.h
new file mode 100644
index 0000000000000..f8d2e246ea0bd
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_privacy_screen.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+/*
+ * Copyright  2019 Google Inc.
+ */
+
+#ifndef __DRM_PRIVACY_SCREEN_H__
+#define __DRM_PRIVACY_SCREEN_H__
+
+#include "intel_display_types.h"
+
+#ifdef CONFIG_ACPI
+bool intel_privacy_screen_present(struct intel_connector *connector);
+void intel_privacy_screen_set_val(struct intel_connector *connector,
+ enum drm_privacy_screen_status val);
+#else
+static bool intel_privacy_screen_present(struct intel_connector *connector)
+{
+ return false;
+}
+
+static void
+intel_privacy_screen_set_val(struct intel_connector *connector,
+ enum drm_privacy_screen_status val)
+{ }
+#endif /* CONFIG_ACPI */
+
+#endif /* __DRM_PRIVACY_SCREEN_H__ */
--
2.25.1.481.gfbce0eb801-goog