Add X86 specific arch init code, which fills the privacy-screen lookup
table by checking for various vendor specific ACPI interfaces for
controlling the privacy-screen.
This initial version only checks for the Lenovo Thinkpad specific ACPI
methods for privacy-screen control.
Reviewed-by: Emil Velikov <emil.l.veli...@gmail.com>
Reviewed-by: Lyude Paul <ly...@redhat.com>
Signed-off-by: Hans de Goede <hdego...@redhat.com>
---
drivers/gpu/drm/Makefile | 2 +-
drivers/gpu/drm/drm_privacy_screen_x86.c | 86 ++++++++++++++++++++++++
include/drm/drm_privacy_screen_machine.h | 5 ++
3 files changed, 92 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/drm_privacy_screen_x86.c
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 788fc37096f6..12997ca5670d 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -32,7 +32,7 @@ drm-$(CONFIG_OF) += drm_of.o
drm-$(CONFIG_PCI) += drm_pci.o
drm-$(CONFIG_DEBUG_FS) += drm_debugfs.o drm_debugfs_crc.o
drm-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
-drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o
+drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o
drm_privacy_screen_x86.o
obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o
diff --git a/drivers/gpu/drm/drm_privacy_screen_x86.c
b/drivers/gpu/drm/drm_privacy_screen_x86.c
new file mode 100644
index 000000000000..a2cafb294ca6
--- /dev/null
+++ b/drivers/gpu/drm/drm_privacy_screen_x86.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * Authors:
+ * Hans de Goede <hdego...@redhat.com>
+ */
+
+#include <linux/acpi.h>
+#include <drm/drm_privacy_screen_machine.h>
+
+#ifdef CONFIG_X86
+static struct drm_privacy_screen_lookup arch_lookup;
+
+struct arch_init_data {
+ struct drm_privacy_screen_lookup lookup;
+ bool (*detect)(void);
+};
+
+#if IS_ENABLED(CONFIG_THINKPAD_ACPI)
+static acpi_status __init acpi_set_handle(acpi_handle handle, u32 level,
+ void *context, void **return_value)
+{
+ *(acpi_handle *)return_value = handle;
+ return AE_CTRL_TERMINATE;
+}
+
+static bool __init detect_thinkpad_privacy_screen(void)
+{
+ union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
+ struct acpi_object_list args = { .count = 1, .pointer = &obj, };
+ acpi_handle ec_handle = NULL;
+ unsigned long long output;
+ acpi_status status;
+
+ /* Get embedded-controller handle */
+ status = acpi_get_devices("PNP0C09", acpi_set_handle, NULL, &ec_handle);
+ if (ACPI_FAILURE(status) || !ec_handle)
+ return false;
+
+ /* And call the privacy-screen get-status method */
+ status = acpi_evaluate_integer(ec_handle, "HKEY.GSSS", &args, &output);
+ if (ACPI_FAILURE(status))
+ return false;
+
+ return (output & 0x10000) ? true : false;
+}
+#endif
+
+static const struct arch_init_data arch_init_data[] __initconst = {
+#if IS_ENABLED(CONFIG_THINKPAD_ACPI)
+ {
+ .lookup = {
+ .dev_id = NULL,
+ .con_id = NULL,
+ .provider = "privacy_screen-thinkpad_acpi",
+ },
+ .detect = detect_thinkpad_privacy_screen,
+ },
+#endif
+};
+
+void __init drm_privacy_screen_lookup_init(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(arch_init_data); i++) {
+ if (!arch_init_data[i].detect())
+ continue;
+
+ pr_info("Found '%s' privacy-screen provider\n",
+ arch_init_data[i].lookup.provider);
+
+ /* Make a copy because arch_init_data is __initconst */
+ arch_lookup = arch_init_data[i].lookup;
+ drm_privacy_screen_lookup_add(&arch_lookup);
+ break;
+ }
+}
+
+void drm_privacy_screen_lookup_exit(void)
+{
+ if (arch_lookup.provider)
+ drm_privacy_screen_lookup_remove(&arch_lookup);
+}
+#endif /* ifdef CONFIG_X86 */
diff --git a/include/drm/drm_privacy_screen_machine.h
b/include/drm/drm_privacy_screen_machine.h
index aaa0d38cce92..02e5371904d3 100644
--- a/include/drm/drm_privacy_screen_machine.h
+++ b/include/drm/drm_privacy_screen_machine.h
@@ -31,11 +31,16 @@ struct drm_privacy_screen_lookup {
void drm_privacy_screen_lookup_add(struct drm_privacy_screen_lookup *lookup);
void drm_privacy_screen_lookup_remove(struct drm_privacy_screen_lookup
*lookup);
+#if IS_ENABLED(CONFIG_DRM_PRIVACY_SCREEN) && IS_ENABLED(CONFIG_X86)
+void drm_privacy_screen_lookup_init(void);
+void drm_privacy_screen_lookup_exit(void);
+#else
static inline void drm_privacy_screen_lookup_init(void)
{
}
static inline void drm_privacy_screen_lookup_exit(void)
{
}
+#endif
#endif
--
2.31.1
