From nobody Fri Apr 10 00:56:47 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8F4AB3D6CA4; Wed, 4 Mar 2026 18:46:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772650005; cv=none; b=ri8fz0OzKUW+KSrieJD46CmpaxbdudW4zEbtwXZ3rE9VfclwaeaY6m9KXHjeJtXQ+maO3VarRmmZxG41saUvvyBFr17wjV9WEmPRq8nZ8n4bKXYccgBnRgupYRd26IUNOgDFJtOzAGtGRiB1mRp5iKa7AJtpYTtuEgK8M3v1e0E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772650005; c=relaxed/simple; bh=pDKiwwoC293ukKLCEm2OubWvL1AdbWE0oxFNVRmKlOI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=lDynX4DRGZETbSezGmIxSzWot9fhl8JO9wkXQ+s2syoQNyakXRw24w4XcWEtFNPLcaVbk9MrNc+SqzK2NZhEH41kwF6mSUhz7GCdJ0OKgyDDmexD1vPaArYhk5G41RinmSM3fTdv8Q+WqhDtUlWTsQfQQZMPbb7O6COl/l37sdM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VUia4e3Z; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VUia4e3Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1239EC2BC9E; Wed, 4 Mar 2026 18:46:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772650005; bh=pDKiwwoC293ukKLCEm2OubWvL1AdbWE0oxFNVRmKlOI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VUia4e3ZhLUZ6fpTsmWjj6YBgNYBwH+NYXlosh4NF63raWGPxn3OUAHJMJMqvqOHO 075x6u/+5VNgAWMdsVofAlC0J6kfiAkIAAYNFNlI3TTJwOJJtSsXBlGo4bFtzNGjUU tChpdLVi1gnfuEcpMrR16spCUrDfZQZd3rJ2GNJyLMtXoijhfMVUgo8cjo3qHVx69K 6LyaH8x+Ml5o7lyngYrJrIqesPTEvGCf5EgWUiPu5HLCW6XGNglbKvxPy+yp3SFKV5 qvCoLWKqvUnMSpRTxLnrWAhkJSbh6eqQHzaZx3RiyGFPc0O+KLWQgOGX0QDpszUT2N bcPxjpcoDdplw== From: "Rafael J. Wysocki" To: chrome-platform@lists.linux.dev Cc: LKML , Linux ACPI , Benson Leung , Tzung-Bi Shih , Enric Balletbo i Serra , Ravi Chandra Sadineni Subject: [PATCH v1 1/6] platform/chrome: Convert ChromeOS privacy-screen driver to platform Date: Wed, 04 Mar 2026 19:42:25 +0100 Message-ID: <3883856.MHq7AAxBmi@rafael.j.wysocki> Organization: Linux Kernel Development In-Reply-To: <2274474.Mh6RI2rZIc@rafael.j.wysocki> References: <2274474.Mh6RI2rZIc@rafael.j.wysocki> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Rafael J. Wysocki" In all cases in which a struct acpi_driver is used for binding a driver to an ACPI device object, a corresponding platform device is created by the ACPI core and that device is regarded as a proper representation of underlying hardware. Accordingly, a struct platform_driver should be used by driver code to bind to that device. There are multiple reasons why drivers should not bind directly to ACPI device objects [1]. Overall, it is better to bind drivers to platform devices than to their ACPI companions, so convert the ChromeOS privacy-screen ACPI driver to a platform one. While this is not expected to alter functionality, it changes sysfs layout and so it will be visible to user space. Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/ [1] Signed-off-by: Rafael J. Wysocki --- .../platform/chrome/chromeos_privacy_screen.c | 41 ++++++++----------- 1 file changed, 18 insertions(+), 23 deletions(-) diff --git a/drivers/platform/chrome/chromeos_privacy_screen.c b/drivers/pl= atform/chrome/chromeos_privacy_screen.c index bb74ddf9af4a..abc5d189a389 100644 --- a/drivers/platform/chrome/chromeos_privacy_screen.c +++ b/drivers/platform/chrome/chromeos_privacy_screen.c @@ -12,6 +12,7 @@ */ =20 #include +#include #include =20 /* @@ -32,11 +33,10 @@ chromeos_privacy_screen_get_hw_state(struct drm_privacy= _screen *drm_privacy_screen) { union acpi_object *obj; - acpi_handle handle; struct device *privacy_screen =3D drm_privacy_screen_get_drvdata(drm_privacy_screen); + acpi_handle handle =3D ACPI_HANDLE(privacy_screen); =20 - handle =3D acpi_device_handle(to_acpi_device(privacy_screen)); obj =3D acpi_evaluate_dsm(handle, &chromeos_privacy_screen_dsm_guid, PRIV_SCRN_DSM_REVID, PRIV_SCRN_DSM_FN_GET_STATUS, NULL); @@ -65,11 +65,9 @@ chromeos_privacy_screen_set_sw_state(struct drm_privacy_= screen enum drm_privacy_screen_status state) { union acpi_object *obj =3D NULL; - acpi_handle handle; struct device *privacy_screen =3D drm_privacy_screen_get_drvdata(drm_privacy_screen); - - handle =3D acpi_device_handle(to_acpi_device(privacy_screen)); + acpi_handle handle =3D ACPI_HANDLE(privacy_screen); =20 if (state =3D=3D PRIVACY_SCREEN_DISABLED) { obj =3D acpi_evaluate_dsm(handle, @@ -104,30 +102,28 @@ static const struct drm_privacy_screen_ops chromeos_p= rivacy_screen_ops =3D { .set_sw_state =3D chromeos_privacy_screen_set_sw_state, }; =20 -static int chromeos_privacy_screen_add(struct acpi_device *adev) +static int chromeos_privacy_screen_probe(struct platform_device *pdev) { struct drm_privacy_screen *drm_privacy_screen =3D - drm_privacy_screen_register(&adev->dev, + drm_privacy_screen_register(&pdev->dev, &chromeos_privacy_screen_ops, - &adev->dev); + &pdev->dev); =20 if (IS_ERR(drm_privacy_screen)) { - dev_err(&adev->dev, "Error registering privacy-screen\n"); + dev_err(&pdev->dev, "Error registering privacy-screen\n"); return PTR_ERR(drm_privacy_screen); } =20 - adev->driver_data =3D drm_privacy_screen; - dev_info(&adev->dev, "registered privacy-screen '%s'\n", + platform_set_drvdata(pdev, drm_privacy_screen); + dev_info(&pdev->dev, "registered privacy-screen '%s'\n", dev_name(&drm_privacy_screen->dev)); =20 return 0; } =20 -static void chromeos_privacy_screen_remove(struct acpi_device *adev) +static void chromeos_privacy_screen_remove(struct platform_device *pdev) { - struct drm_privacy_screen *drm_privacy_screen =3D acpi_driver_data(adev); - - drm_privacy_screen_unregister(drm_privacy_screen); + drm_privacy_screen_unregister(platform_get_drvdata(pdev)); } =20 static const struct acpi_device_id chromeos_privacy_screen_device_ids[] = =3D { @@ -136,17 +132,16 @@ static const struct acpi_device_id chromeos_privacy_s= creen_device_ids[] =3D { }; MODULE_DEVICE_TABLE(acpi, chromeos_privacy_screen_device_ids); =20 -static struct acpi_driver chromeos_privacy_screen_driver =3D { - .name =3D "chromeos_privacy_screen_driver", - .class =3D "ChromeOS", - .ids =3D chromeos_privacy_screen_device_ids, - .ops =3D { - .add =3D chromeos_privacy_screen_add, - .remove =3D chromeos_privacy_screen_remove, +static struct platform_driver chromeos_privacy_screen_driver =3D { + .probe =3D chromeos_privacy_screen_probe, + .remove =3D chromeos_privacy_screen_remove, + .driver =3D { + .name =3D "chromeos_privacy_screen_driver", + .acpi_match_table =3D chromeos_privacy_screen_device_ids, }, }; =20 -module_acpi_driver(chromeos_privacy_screen_driver); +module_platform_driver(chromeos_privacy_screen_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("ChromeOS ACPI Privacy Screen driver"); MODULE_AUTHOR("Rajat Jain "); --=20 2.51.0