From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793686716; b=icWPqCH5GFbyny/gzqz2yK/ohushzITgz4aTLxpPSy5NR1DmIRKfAq77QYsGC0f0EztI mycvdnhV/24HTyZT/Rx//FvCL1HJh4tjScYoVNFUcZhcMlv6pXNDjHhVs76JSeuzx1Uhf LL7tQAbbgy10HQEJh+4G1PfxJbUGFw6LLdkdAQ2sdoYQXhfAmvVbpcDYp7vQpwwiJV7WB cvBvKHf7p+5oXfqYbFrpVd/jtu9DieQS6p/kzQGhJvgpsyWL+KYngoJD5WOOaViemkJOi 7k4o9+WILiVf+9T0RQhISbt50NxpWmOwxW1b/pbdQ5b62kR80miN3eyzkxwqSh3Dpeg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793686716; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=IE9SYHIo5vGX9Mw3uWmKYIJoNxMrGsdiRfVObJODqcU=; b=SfHgGtvfWEjP2AOrnkTcUl5kubjJimlkDvCVng5PYS+7+DdI/DDj2j8nFKOjaoOCnu3c bHTnv1quz1hcpGChj1241vgLtzjAaaYY1tn4Ml/o9zTCX5aBWyzExzxPRT7JbVrWWoyZE EViiXAE94jxC0wDw5s2B7YxUUOSA3j780/r+iEO/xwRKYHdJRXorCkyk/JKzvqe4yEwao 7G9Vkbesgd5i2gpT3+ICQKwBR0T83gGaez0T0dIuRyBxY8YlPvbdguXS4huOJN6ysmSzI KtfAyoLb2G4kxAW8yIf4GAqIuWybYYGhkSipyfPD4RyGDZ+VlyOssGY0/DhUpJwRsaQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=c2q8Jqq6; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9423A606A329 for ; Tue, 3 Nov 2026 06:18:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=c2q8Jqq6 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 137271F000C1; Tue, 3 Nov 2026 06:18:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793686716; bh=IE9SYHIo5vGX9Mw3uWmKYIJoNxMrGsdiRfVObJODqcU=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=c2q8Jqq67qC0sDJyc63O/fELi8OxW343c4MJZ8Q89/knmobJ6aZiZiVgX7b49PQ9D 5DWma2lgQ+EJXoJeGCIHT8g5UfKk36Dbq/W6s4UAweGWMFcgSqERwPYPzcJ8NGZWDZ W9csksRWFHK40i0Rcjxl28778blW5XG2Ifrmtb9vXx/Z+K7av/CSRfopfnlE8VRU1D aBvXsAzrx+KvJtzV/yZhg2sSBUKncGtfUgreVb11VRtewl2jzmW/iOAMa8DbHq93CB zF6ssP3+Nv+a0tUFmKBCUwN1nTrVtwgJQ/9zWqmgBKWso9K+v0ogoXNQFnYeim9IBH 2gZ9P9Yxrj+yQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v3] USB: hub: call ACPI _PRR reset during port power-cycle on enumeration failure Reply-To: sashiko-reviews@lists.linux.dev To: "Mario Limonciello" Cc: linux-usb@vger.kernel.org In-Reply-To: <20260706080117.3754550-1-v3-1-0e3069228fe9@kernel.org> References: <20260706080117.3754550-1-v3-1-0e3069228fe9@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 03 Nov 2026 06:18:35 +0000 X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > Some USB-connected devices (e.g. MT7925 Bluetooth on Dell laptops) expose > their hardware reset line via an ACPI Power Resource for Reset (_PRR) > rather than relying solely on VBUS cycling for recovery. When the reset > GPIO gets stuck low the device stops responding on USB; a VBUS power-cycle > alone cannot recover it because the chip remains in reset regardless of > VBUS state. >=20 > Add usb_acpi_port_prr_reset() in usb-acpi.c that, given a hub device and > one-based port number, looks up the port's ACPI companion handle, evaluat= es > _PRR to obtain the power-resource reference, and then calls _RST on that > reference to toggle the reset line. The function is a no-op if the port > has no ACPI handle or no _PRR method, so it is safe to call unconditional= ly > for every port. >=20 > Wire it into hub_port_connect() during the mid-retry VBUS power-cycle > [ ... ] >=20 > Signed-off-by: Chia-Lin Kao (AceLan) > Reviewed-by: Mario Limonciello (AMD) > Link: https://patch.msgid.link/20260706080117.3754550-1-acelan.kao@canoni= cal.com > Signed-off-by: Mario Limonciello (AMD) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260706080117.3754= 550-1-v3-1-0e3069228fe9@kernel.org?part=3D1