From patchwork Tue Jul 19 13:01:44 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sinan Kaya X-Patchwork-Id: 9237185 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 231136075D for ; Tue, 19 Jul 2016 13:05:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 13A4626A4D for ; Tue, 19 Jul 2016 13:05:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 080D226D08; Tue, 19 Jul 2016 13:05:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id DC25826A4D for ; Tue, 19 Jul 2016 13:05:54 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bPUgt-0000k5-0W; Tue, 19 Jul 2016 13:04:03 +0000 Received: from smtp.codeaurora.org ([198.145.29.96]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bPUfL-0007zg-O8 for linux-arm-kernel@lists.infradead.org; Tue, 19 Jul 2016 13:02:31 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id D957F61283; Tue, 19 Jul 2016 13:02:08 +0000 (UTC) Received: from drakthul.qualcomm.com (global_nat1_iad_fw.qualcomm.com [129.46.232.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 16656601B2; Tue, 19 Jul 2016 13:02:06 +0000 (UTC) From: Sinan Kaya To: kvm@vger.kernel.org, timur@codeaurora.org, cov@codeaurora.org, jcm@redhat.com, alex.williamson@redhat.com, eric.auger@redhat.com Subject: [PATCH V11 4/9] vfio: platform: add support for ACPI probe Date: Tue, 19 Jul 2016 09:01:44 -0400 Message-Id: <1468933309-19735-5-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1468933309-19735-1-git-send-email-okaya@codeaurora.org> References: <1468933309-19735-1-git-send-email-okaya@codeaurora.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160719_060228_289605_99FFF460 X-CRM114-Status: GOOD ( 17.61 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Baptiste Reynal , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Sinan Kaya , linux-acpi@vger.kernel.org, agross@codeaurora.org, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The code is using the compatible DT string to associate a reset driver with the actual device itself. The compatible string does not exist on ACPI based systems. HID is the unique identifier for a device driver instead. Signed-off-by: Sinan Kaya --- drivers/vfio/platform/vfio_platform_common.c | 64 ++++++++++++++++++++++++--- drivers/vfio/platform/vfio_platform_private.h | 1 + 2 files changed, 60 insertions(+), 5 deletions(-) diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c index 6be92c3..6aa45e5 100644 --- a/drivers/vfio/platform/vfio_platform_common.c +++ b/drivers/vfio/platform/vfio_platform_common.c @@ -13,6 +13,7 @@ */ #include +#include #include #include #include @@ -49,6 +50,27 @@ static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat, return reset_fn; } +static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev, + struct device *dev) +{ + struct acpi_device *adev; + + if (acpi_disabled) + return -ENOENT; + + adev = ACPI_COMPANION(dev); + if (!adev) { + pr_err("VFIO: ACPI companion device not found for %s\n", + vdev->name); + return -ENODEV; + } + +#ifdef CONFIG_ACPI + vdev->acpihid = acpi_device_hid(adev); +#endif + return WARN_ON(!vdev->acpihid) ? -EINVAL : 0; +} + static bool vfio_platform_has_reset(struct vfio_platform_device *vdev) { return vdev->of_reset ? true : false; @@ -547,6 +569,37 @@ static const struct vfio_device_ops vfio_platform_ops = { .mmap = vfio_platform_mmap, }; +int vfio_platform_of_probe(struct vfio_platform_device *vdev, + struct device *dev) +{ + int ret; + + ret = device_property_read_string(dev, "compatible", + &vdev->compat); + if (ret) + pr_err("VFIO: cannot retrieve compat for %s\n", + vdev->name); + + return ret; +} + +/* + * There can be two kernel build combinations. One build where + * ACPI is not selected in Kconfig and another one with the ACPI Kconfig. + * + * In the first case, vfio_platform_acpi_probe will return since + * acpi_disabled is 1. DT user will not see any kind of messages from + * ACPI. + * + * In the second case, both DT and ACPI is compiled in but the system is + * booting with any of these combinations. + * + * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine + * terminates immediately without any messages. + * + * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are + * valid checks. We cannot claim that this system is DT. + */ int vfio_platform_probe_common(struct vfio_platform_device *vdev, struct device *dev) { @@ -556,11 +609,12 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, if (!vdev) return -EINVAL; - ret = device_property_read_string(dev, "compatible", &vdev->compat); - if (ret) { - pr_err("VFIO: cannot retrieve compat for %s\n", vdev->name); - return -EINVAL; - } + ret = vfio_platform_acpi_probe(vdev, dev); + if (ret) + ret = vfio_platform_of_probe(vdev, dev); + + if (ret) + return ret; vdev->device = dev; diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h index 71ed7d1..ba9e4f8 100644 --- a/drivers/vfio/platform/vfio_platform_private.h +++ b/drivers/vfio/platform/vfio_platform_private.h @@ -58,6 +58,7 @@ struct vfio_platform_device { struct mutex igate; struct module *parent_module; const char *compat; + const char *acpihid; struct module *reset_module; struct device *device;