IdeaPads dropped support for VPCCMD_W_CAMERA somewhere between 2014-2016, none of the IdeaPads produced after that I tested supports it. Fortunately I found a way to check it; if the DSDT has camera device(s) defined, it shouldn't have working VPCCMD_W_CAMERA, thus camera_power shouldn't be exposed to sysfs. To accomplish this, walk the ACPI namespace in ideapad_check_features and check the devices starting with "CAM". Tested on 520-15IKB and Legion Y520, which successfully didn't expose the camera_power attribute. Link: https://www.spinics.net/lists/platform-driver-x86/msg26147.html Signed-off-by: Eray Orçunus <erayorcunus@xxxxxxxxx> --- drivers/platform/x86/ideapad-laptop.c | 53 ++++++++++++++++++++++++++- 1 file changed, 52 insertions(+), 1 deletion(-) diff --git a/drivers/platform/x86/ideapad-laptop.c b/drivers/platform/x86/ideapad-laptop.c index f3d4f2beda07..65eea2e65bbe 100644 --- a/drivers/platform/x86/ideapad-laptop.c +++ b/drivers/platform/x86/ideapad-laptop.c @@ -149,6 +149,7 @@ struct ideapad_private { bool fn_lock : 1; bool hw_rfkill_switch : 1; bool kbd_bl : 1; + bool cam_ctrl_via_ec : 1; bool touchpad_ctrl_via_ec : 1; bool usb_charging : 1; } features; @@ -163,6 +164,26 @@ static bool no_bt_rfkill; module_param(no_bt_rfkill, bool, 0444); MODULE_PARM_DESC(no_bt_rfkill, "No rfkill for bluetooth."); +static char *cam_device_prefix = "CAM"; + +static acpi_status acpi_find_device_callback(acpi_handle handle, u32 level, + void *context, void **return_value) +{ + char buffer[8]; + struct acpi_buffer ret_buf; + + ret_buf.length = sizeof(buffer); + ret_buf.pointer = buffer; + + if (ACPI_SUCCESS(acpi_get_name(handle, ACPI_SINGLE_NAME, &ret_buf))) + if (strncmp(ret_buf.pointer, context, strlen(context)) == 0) { + *return_value = handle; + return AE_CTRL_TERMINATE; + } + + return AE_OK; +} + /* * ACPI Helpers */ @@ -675,7 +696,7 @@ static umode_t ideapad_is_visible(struct kobject *kobj, bool supported = true; if (attr == &dev_attr_camera_power.attr) - supported = test_bit(CFG_CAP_CAM_BIT, &priv->cfg); + supported = priv->features.cam_ctrl_via_ec; else if (attr == &dev_attr_conservation_mode.attr) supported = priv->features.conservation_mode; else if (attr == &dev_attr_fan_mode.attr) @@ -1523,10 +1544,40 @@ static const struct dmi_system_id hw_rfkill_list[] = { static void ideapad_check_features(struct ideapad_private *priv) { acpi_handle handle = priv->adev->handle; + acpi_handle pci_handle; + acpi_handle temp_handle = NULL; unsigned long val; + acpi_status status; priv->features.hw_rfkill_switch = dmi_check_system(hw_rfkill_list); + /* + * Some IdeaPads have camera switch via EC (mostly older ones), + * some don't. Fortunately we know that if DSDT contains device + * object for the camera, camera isn't switchable via EC. + * So, let's walk the namespace and try to find CAM* object. + * If we can't find it, set cam_ctrl_via_ec to true. + */ + + priv->features.cam_ctrl_via_ec = false; + + if (test_bit(CFG_CAP_CAM_BIT, &priv->cfg)) { + status = acpi_get_handle(handle, "^^^", &pci_handle); + if (ACPI_SUCCESS(status)) { + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, pci_handle, + ACPI_UINT32_MAX, + acpi_find_device_callback, + NULL, cam_device_prefix, + &temp_handle); + + if (ACPI_SUCCESS(status) && temp_handle == NULL) + priv->features.cam_ctrl_via_ec = true; + + } else + dev_warn(&priv->platform_device->dev, + "Could not find PCI* node in the namespace\n"); + } + /* Most ideapads with ELAN0634 touchpad don't use EC touchpad switch */ priv->features.touchpad_ctrl_via_ec = !acpi_dev_present("ELAN0634", NULL, -1); -- 2.34.1
