From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.13]) (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 9991E405C3F; Thu, 30 Jul 2026 11:03:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785409429; cv=none; b=cUX9Jj9xr94n3uvZtdingHhID0hGc/YAQSJ/scuWe10hcEMukTiulnD9iDDTaccQQRRjXAb4ar/B7qOChoNVpGMJZD7Jsu7MF//Nv6pJ4lofSgGYGg4QsWZPvXKwTlyGa/VoYHvLghzAB1fmhL6qbld0Lvs2KsPEPL6Ob05s5sw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785409429; c=relaxed/simple; bh=vR3KOP2wNni1PSsIaEaFJckIWBDQP1BYlMo4rQ2E4NA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HCVcyYZ4LzQ9rXnkItpsxU8UmPRMikgovVRSS0EFcMLqxV7KqehqixQWwVi6L9wggB+fr0/MrUBgAfx8PTkyR0rd3DnwAHrTmvwpR5/pf9lXoQNemkZO2UbMn7h/VLPwGsVwTpRn6xoctgK0BGGlbVkCUdLhisSqQBdJEy4sJJI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=NHOUfCx4; arc=none smtp.client-ip=198.175.65.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="NHOUfCx4" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1785409428; x=1816945428; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=vR3KOP2wNni1PSsIaEaFJckIWBDQP1BYlMo4rQ2E4NA=; b=NHOUfCx4NHSOU6afwgQH7o6gdMN37ybfWzw7Q1pBkkcj4uHZ5SQ4KJPN gE4Ks2LZjpa0vCOrl/e20ziSYGcy2LBvCo3EzTpSo3dvZx0vdLq175Fq2 e2PWS427EAgY6QKF0ZGG2F7ej1vHin/cx4oPKR6Ja3M9LEbDuBSZ0KDoo +OSCgJQGiXDdYC/N51FLARPpmOsuMdpcwhkEF3x/8a9fHy+/oU0EBe23a mTR5ZRGpk1erYqTaeH7enA3h9RApVlMbWwuWStYQXETe0S9g8VZ2MxfrC U9MzE9+JDqTpLAEGxzirQj61ujZqwnuzj0ZgJ48DsokHvibOkCw/1ctcI g==; X-CSE-ConnectionGUID: sysherMiQM2uzsA0onMH5g== X-CSE-MsgGUID: 9N2ysVSxQoOj+KlO9C0lOw== X-IronPort-AV: E=McAfee;i="6800,10657,11859"; a="97182103" X-IronPort-AV: E=Sophos;i="6.25,194,1779174000"; d="scan'208";a="97182103" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jul 2026 04:03:48 -0700 X-CSE-ConnectionGUID: lnFdRTJDQ8+JwW2klVOUzg== X-CSE-MsgGUID: 0/0RwJK1TSax64VhvQt5nw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,194,1779174000"; d="scan'208";a="256933272" Received: from black.igk.intel.com ([10.91.253.5]) by fmviesa007.fm.intel.com with ESMTP; 30 Jul 2026 04:03:44 -0700 Received: by black.igk.intel.com (Postfix, from userid 1008) id 5AF4999; Thu, 30 Jul 2026 13:03:43 +0200 (CEST) Date: Thu, 30 Jul 2026 13:03:43 +0200 From: Heikki Krogerus To: Raag Jadav , Mika Westerberg Cc: Matthew Brost , Thomas =?iso-8859-1?Q?Hellstr=F6m?= , Rodrigo Vivi , Andy Shevchenko , Andi Shyti , Ramesh Babu B , "Michael J. Ruhl" , linux-kernel@vger.kernel.org, intel-xe@lists.freedesktop.org, stable@vger.kernel.org Subject: Re: [PATCH v6 3/3] drm/xe/i2c: Keep the i2c controller always enabled Message-ID: References: <20260722133554.2079612-1-heikki.krogerus@linux.intel.com> <20260722133554.2079612-4-heikki.krogerus@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jul 29, 2026 at 05:34:26PM +0200, Raag Jadav wrote: > On Wed, Jul 22, 2026 at 03:35:54PM +0200, Heikki Krogerus wrote: > > Some platforms make an assumption that the i2c controller's > > enabled state indicates also the power state of the > > controller. This can create a problem when the controller is > > in disabled state, because the hardware may assume > > incorrectly that it is then also in low-power state. > > > > To fix this, the controller is kept enabled by taking over > > the IC_ENABLE register. The controller has to be disabled > > when the configuration is updated and when the target > > address or the slave address are assigned, so disabling it > > when IC_CON, IC_TAR or IC_SAR registers are programmed, and > > then re-enabling it again. > > > > Fixes: f0e53aadd702 ("drm/xe: Support for I2C attached MCUs") > > Cc: stable@vger.kernel.org > > Signed-off-by: Heikki Krogerus > > I'll rely on Andy and Mika's disposition on this one. Mika should be back from vacation. -- heikki