From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 D187F53A8A5 for ; Wed, 9 Sep 2026 11:52:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788954732; cv=none; b=qVRlqPSOadDDkyNN6xlHrklqnIaq4Fcx8YpHq1r5WtZ1HCgJxPgb9/k2uaYMTEhBYE4AbQO6vPqXtMmpsEFvL/PP6QHeQMyGO43PSwsPSQxOpMz3HsT9Pq7ih1XFkstCHzXCuALRH8diuOXKNjdzBDS5twps77Fa18q2neJIv7I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788954732; c=relaxed/simple; bh=e9UCKjXcDpdavf/jzBZ5jZ3zksD4mpNxBflclUIlJQk=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=leUN0gPM0VBzqIyHz9S5m0LADoYxYgbE5IhXI4Ocj+Y38vFs2JKXPtc/2SQaK4KBRzX5K72Uqcpds3x4cWez5KB2XzYmt0b9CNrtX75+NMzv+aId+YWXYy3NODzBMFZB5IZ0xHxE/W5aFMtVuNGKjpov5cyo/VD/Cz3H0vPP/0g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yZXe+olY; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="yZXe+olY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 39C291F00A3A; Wed, 9 Sep 2026 11:52:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788954730; bh=HW2MXEzMAGq8tlebMHqqKL3D9aGGFHWq6lOwsGd3fm0=; h=Subject:To:Cc:From:Date; b=yZXe+olY+N8+QqheTAn6DQV71dQDFsyq3Zgh+1FVH1/klSrEYiJBeRo/4ver5PS9T lrNj9qaKWo+yS7iXuQF5rnVkkf+bG7rLR+a3U22ms8s9WZgscjeBOTzqmVUo5bgPXN 5n+hsBuPbPFRUMWFoNHeSJzwwfY620TGxM51A7Fg= Subject: FAILED: patch "[PATCH] drm/xe/i2c: Keep the i2c controller always enabled" failed to apply to 7.2-stable tree To: heikki.krogerus@linux.intel.com,rodrigo.vivi@intel.com Cc: From: Date: Wed, 09 Sep 2026 13:42:57 +0200 Message-ID: <2026090957-lilac-mocha-69d6@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 7.2-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-7.2.y git checkout FETCH_HEAD git cherry-pick -x 244abef7f280a6a84297bfab5fd2e77147bc419a # git commit -s git send-email --to '' --in-reply-to '2026090957-lilac-mocha-69d6@gregkh' --subject-prefix 'PATCH 7.2.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 244abef7f280a6a84297bfab5fd2e77147bc419a Mon Sep 17 00:00:00 2001 From: Heikki Krogerus Date: Tue, 11 Aug 2026 14:10:08 +0200 Subject: [PATCH] drm/xe/i2c: Keep the i2c controller always enabled 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 Reviewed-by: Rodrigo Vivi Link: https://patch.msgid.link/20260811121008.1493015-4-heikki.krogerus@linux.intel.com Signed-off-by: Rodrigo Vivi (cherry picked from commit 76cc14e2faed1adae20f4ee144ead0e3a7566c49) Signed-off-by: Rodrigo Vivi diff --git a/drivers/gpu/drm/xe/xe_i2c.c b/drivers/gpu/drm/xe/xe_i2c.c index 32767570e43d..d8fa68206f41 100644 --- a/drivers/gpu/drm/xe/xe_i2c.c +++ b/drivers/gpu/drm/xe/xe_i2c.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -215,11 +216,40 @@ void xe_i2c_irq_postinstall(struct xe_device *xe) xe_mmio_rmw32(mmio, I2C_CONFIG_CMD, PCI_COMMAND_INTX_DISABLE, 0); } +/* See "Disabling DW_apb_i2c" in the DesignWare DW_abp_i2c databook. */ +static void xe_i2c_disable(struct xe_i2c *i2c) +{ + int timeout = 100; + u32 status; + + xe_mmio_rmw32(i2c->mmio, I2C_REG(DW_IC_ENABLE), DW_IC_ENABLE_ENABLE, 0); + + do { + status = xe_mmio_read32(i2c->mmio, I2C_REG(DW_IC_ENABLE_STATUS)); + if (!(status & DW_IC_ENABLE_ENABLE)) + return; + /* Can't sleep here. */ + udelay(25); + } while (timeout--); + + dev_warn(i2c->drm_dev, "timeout in disabling i2c adapter\n"); +} + static int xe_i2c_read(void *context, unsigned int reg, unsigned int *val) { struct xe_i2c *i2c = context; - *val = xe_mmio_read32(i2c->mmio, XE_REG(reg + I2C_MEM_SPACE_OFFSET)); + *val = xe_mmio_read32(i2c->mmio, I2C_REG(reg)); + + switch (reg) { + case DW_IC_ENABLE: + case DW_IC_ENABLE_STATUS: + FIELD_MODIFY(DW_IC_ENABLE_ENABLE, val, + i2c->ic_enable & DW_IC_ENABLE_ENABLE); + break; + default: + break; + } return 0; } @@ -229,6 +259,23 @@ static int xe_i2c_write(void *context, unsigned int reg, unsigned int val) struct xe_i2c *i2c = context; switch (reg) { + case DW_IC_CON: + case DW_IC_TAR: + case DW_IC_SAR: + /* Disable the controller. */ + xe_i2c_disable(i2c); + + /* Write the register. */ + xe_mmio_write32(i2c->mmio, I2C_REG(reg), val); + + /* Enable the controller. */ + xe_mmio_rmw32(i2c->mmio, I2C_REG(DW_IC_ENABLE), 0, DW_IC_ENABLE_ENABLE); + return 0; + case DW_IC_ENABLE: + i2c->ic_enable = val; + /* Other fields can be updated except the enable bit. */ + val |= DW_IC_ENABLE_ENABLE; + break; case DW_IC_SMBUS_INTR_MASK: /* Make sure the Alert is never masked. */ val |= DW_IC_SMBUS_INTR_ALERT; diff --git a/drivers/gpu/drm/xe/xe_i2c.h b/drivers/gpu/drm/xe/xe_i2c.h index b200966b0048..d63adacfefe7 100644 --- a/drivers/gpu/drm/xe/xe_i2c.h +++ b/drivers/gpu/drm/xe/xe_i2c.h @@ -37,6 +37,7 @@ struct xe_i2c { struct platform_device *pdev; struct i2c_adapter *adapter; struct i2c_client *client[XE_I2C_MAX_CLIENTS]; + unsigned int ic_enable; struct notifier_block bus_notifier; struct work_struct work;