From patchwork Tue Feb 25 12:38:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 11403555 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DF93B13A4 for ; Tue, 25 Feb 2020 12:38:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C06E121927 for ; Tue, 25 Feb 2020 12:38:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730035AbgBYMiH (ORCPT ); Tue, 25 Feb 2020 07:38:07 -0500 Received: from mga17.intel.com ([192.55.52.151]:14139 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729238AbgBYMiH (ORCPT ); Tue, 25 Feb 2020 07:38:07 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 Feb 2020 04:38:06 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,484,1574150400"; d="scan'208";a="255937950" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga002.jf.intel.com with ESMTP; 25 Feb 2020 04:38:03 -0800 Received: by black.fi.intel.com (Postfix, from userid 1001) id 54532489; Tue, 25 Feb 2020 14:38:02 +0200 (EET) From: Mika Westerberg To: Guenter Roeck , Jean Delvare , Wim Van Sebroeck , Wolfram Sang Cc: Martin Volf , Andy Shevchenko , Jarkko Nikula , Mika Westerberg , linux-i2c@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/3] i2c: i801: Do not add ICH_RES_IO_SMI if PMC device is not present Date: Tue, 25 Feb 2020 15:38:02 +0300 Message-Id: <20200225123802.88984-4-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200225123802.88984-1-mika.westerberg@linux.intel.com> References: <20200225123802.88984-1-mika.westerberg@linux.intel.com> MIME-Version: 1.0 Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org Martin noticed that nct6775 driver does not load properly on his system in v5.4+ kernels. The issue was bisected to commit b84398d6d7f9 ("i2c: i801: Use iTCO version 6 in Cannon Lake PCH and beyond") but it is likely not the culprit because the faulty code has been in the driver already since commit 9424693035a5 ("i2c: i801: Create iTCO device on newer Intel PCHs"). So more likely some commit that added PCI IDs of recent chipsets made the driver to create the iTCO_wdt device on Martins system. The issue was debugged to be PCI configuration access to the PMC device that is not present. This returns all 1's when read and this caused the iTCO_wdt driver to accidentally request resourses used by nct6775. Fix this by checking that the PMC device is there and only then populate the iTCO_wdt ICH_RES_IO_SMI resource. Since the resource is now optional the iTCO_wdt driver should continue to work on recent systems without it. Link: https://lore.kernel.org/linux-hwmon/CAM1AHpQ4196tyD=HhBu-2donSsuogabkfP03v1YF26Q7_BgvgA@mail.gmail.com/ Fixes: 9424693035a5 ("i2c: i801: Create iTCO device on newer Intel PCHs") Reported-by: Martin Volf Signed-off-by: Mika Westerberg --- drivers/i2c/busses/i2c-i801.c | 45 +++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 18 deletions(-) diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index ca4f096fef74..7fa58375bd4b 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -1519,7 +1519,7 @@ static DEFINE_SPINLOCK(p2sb_spinlock); static struct platform_device * i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev, - struct resource *tco_res) + struct resource *tco_res, size_t nres) { struct resource *res; unsigned int devfn; @@ -1563,7 +1563,7 @@ i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev, res->flags = IORESOURCE_MEM; return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1, - tco_res, 3, &spt_tco_platform_data, + tco_res, nres + 1, &spt_tco_platform_data, sizeof(spt_tco_platform_data)); } @@ -1574,19 +1574,20 @@ static const struct itco_wdt_platform_data cnl_tco_platform_data = { static struct platform_device * i801_add_tco_cnl(struct i801_priv *priv, struct pci_dev *pci_dev, - struct resource *tco_res) + struct resource *tco_res, size_t nres) { return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1, - tco_res, 2, &cnl_tco_platform_data, + tco_res, nres, &cnl_tco_platform_data, sizeof(cnl_tco_platform_data)); } static void i801_add_tco(struct i801_priv *priv) { u32 base_addr, tco_base, tco_ctl, ctrl_val; - struct pci_dev *pci_dev = priv->pci_dev; + struct pci_dev *pmc_dev, *pci_dev = priv->pci_dev; struct resource tco_res[3], *res; unsigned int devfn; + size_t nres = 0; /* If we have ACPI based watchdog use that instead */ if (acpi_has_watchdog()) @@ -1606,29 +1607,37 @@ static void i801_add_tco(struct i801_priv *priv) res->start = tco_base & ~1; res->end = res->start + 32 - 1; res->flags = IORESOURCE_IO; + nres++; /* * Power Management registers. */ devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 2); - pci_bus_read_config_dword(pci_dev->bus, devfn, ACPIBASE, &base_addr); + pmc_dev = pci_get_slot(pci_dev->bus, devfn); + if (pmc_dev) { + pci_read_config_dword(pmc_dev, ACPIBASE, &base_addr); - res = &tco_res[ICH_RES_IO_SMI]; - res->start = (base_addr & ~1) + ACPIBASE_SMI_OFF; - res->end = res->start + 3; - res->flags = IORESOURCE_IO; + res = &tco_res[ICH_RES_IO_SMI]; + res->start = (base_addr & ~1) + ACPIBASE_SMI_OFF; + res->end = res->start + 3; + res->flags = IORESOURCE_IO; + nres++; - /* - * Enable the ACPI I/O space. - */ - pci_bus_read_config_dword(pci_dev->bus, devfn, ACPICTRL, &ctrl_val); - ctrl_val |= ACPICTRL_EN; - pci_bus_write_config_dword(pci_dev->bus, devfn, ACPICTRL, ctrl_val); + /* + * Enable the ACPI I/O space. + */ + pci_read_config_dword(pmc_dev, ACPICTRL, &ctrl_val); + ctrl_val |= ACPICTRL_EN; + pci_write_config_dword(pmc_dev, ACPICTRL, ctrl_val); + + pci_dev_put(pmc_dev); + } if (priv->features & FEATURE_TCO_CNL) - priv->tco_pdev = i801_add_tco_cnl(priv, pci_dev, tco_res); + priv->tco_pdev = i801_add_tco_cnl(priv, pci_dev, tco_res, nres); else - priv->tco_pdev = i801_add_tco_spt(priv, pci_dev, tco_res); + priv->tco_pdev = i801_add_tco_spt(priv, pci_dev, tco_res, nres); + if (IS_ERR(priv->tco_pdev)) dev_warn(&pci_dev->dev, "failed to create iTCO device\n");