From patchwork Fri Apr 7 10:40:52 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 748162 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3vzx260N3Wz9s7s for ; Fri, 7 Apr 2017 20:41:02 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932580AbdDGKlB (ORCPT ); Fri, 7 Apr 2017 06:41:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53970 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932299AbdDGKlA (ORCPT ); Fri, 7 Apr 2017 06:41:00 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 72654C04BD40; Fri, 7 Apr 2017 10:40:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 72654C04BD40 Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=hdegoede@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 72654C04BD40 Received: from shalem.localdomain.com (ovpn-116-210.ams2.redhat.com [10.36.116.210]) by smtp.corp.redhat.com (Postfix) with ESMTP id 41F6784423; Fri, 7 Apr 2017 10:40:57 +0000 (UTC) From: Hans de Goede To: Darren Hart , Wolfram Sang , Andy Shevchenko , Mika Westerberg Cc: Hans de Goede , platform-driver-x86@vger.kernel.org, Takashi Iwai , linux-i2c@vger.kernel.org, Lukas Wunner Subject: [PATCH v6 1/4] ACPU: utils: Add new acpi_dev_present helper Date: Fri, 7 Apr 2017 12:40:52 +0200 Message-Id: <20170407104055.25035-1-hdegoede@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Fri, 07 Apr 2017 10:40:59 +0000 (UTC) Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org acpi_dev_found just iterates over all ACPI-ids and sees if one matches. This means that it will return true for devices which are in the dsdt but disabled (their _STA method returns 0). For some drivers it is useful to be able to check if a certain HID is not only present in the namespace, but also actually present as in acpi_device_is_present() will return true for the device. For example because if a certain device is present then the driver will want to use an extcon or IIO adc channel provided by that device. This commit adds a new acpi_dev_present helper which drivers can use to this end. Like acpi_dev_found, acpi_dev_present take a HID as argument, but it also has 2 extra optional arguments to only check for an ACPI device with a specific UID and/or HRV value. This makes it more generic and allows it to replace custom code doing similar checks in several places. Arguably acpi_dev_present is what acpi_dev_found should have been, but there are too many users to just change acpi_dev_found without the risk of breaking something. Cc: Mika Westerberg Cc: Lukas Wunner Signed-off-by: Hans de Goede --- Changes in v2: -Switch to using bus_find_device() to avoid "Traversing the namespace over and over" -Add optional (may be NULL / -1) uid and hrv arguments, this will allow this new function to replace the custom code for this in drivers/firmware/efi/dev-path-parser.c as well as in sound/soc/intel/common/sst-match-acpi.c and will allow it to be used to implement blacklists to avoid loading the ACPI ac / battery driver on systems which have a PMIC / charger acpi device with a native driver which offers a better (often working vs not working) user experience -Dropped Mika's reviewd by as this is almost a total rewrite --- drivers/acpi/utils.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++ include/acpi/acpi_bus.h | 1 + include/linux/acpi.h | 5 ++++ 3 files changed, 78 insertions(+) diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c index 22c0995..d879237 100644 --- a/drivers/acpi/utils.c +++ b/drivers/acpi/utils.c @@ -736,6 +736,78 @@ bool acpi_dev_found(const char *hid) } EXPORT_SYMBOL(acpi_dev_found); +struct acpi_dev_present_info { + struct acpi_device_id hid[2]; + const char *uid; + int hrv; +}; + +static int acpi_dev_present_cb(struct device *dev, void *data) +{ + struct acpi_device *adev = to_acpi_device(dev); + struct acpi_dev_present_info *match = data; + unsigned long long hrv; + acpi_status status; + + if (acpi_match_device_ids(adev, match->hid)) + return 0; + + if (match->uid && adev->pnp.unique_id && + strcmp(adev->pnp.unique_id, match->uid)) + return 0; + + if (match->uid && !adev->pnp.unique_id && + strcmp("0", match->uid)) + return 0; + + if (match->hrv == -1) + return 1; + + status = acpi_evaluate_integer(adev->handle, "_HRV", NULL, &hrv); + if (ACPI_FAILURE(status)) + return 0; + + return hrv == match->hrv; +} + +/** + * acpi_dev_present - Detect that a given ACPI device is present + * @hid: Hardware ID of the device. + * @uid: Unique ID of the device, pass "0" for devices without a _UID, + * pass NULL to not check _UID + * @hrv: Hardware Revision of the device, pass -1 to not check _HRV + * + * Return %true if a matching device was present at the moment of invocation. + * Note that if the device is pluggable, it may since have disappeared. + * + * Note that unlike acpi_dev_found() this function checks the status + * of the device so for devices which are present in the dsdt, but + * which are disabled (their _STA callback returns 0) this function + * will return false. + * + * For this function to work, acpi_bus_scan() must have been executed + * which happens in the subsys_initcall() subsection. Hence, do not + * call from a subsys_initcall() or earlier (use acpi_get_devices() + * instead). Calling from module_init() is fine (which is synonymous + * with device_initcall()). + */ +bool acpi_dev_present(const char *hid, const char *uid, int hrv) +{ + struct acpi_dev_present_info match; + struct device *dev; + + strlcpy(match.hid[0].id, hid, sizeof(match.hid[0].id)); + match.hid[1].id[0] = 0; + match.uid = uid; + match.hrv = hrv; + + dev = bus_find_device(&acpi_bus_type, NULL, &match, + acpi_dev_present_cb); + + return dev ? true : false; +} +EXPORT_SYMBOL(acpi_dev_present); + /* * acpi_backlight= handling, this is done here rather then in video_detect.c * because __setup cannot be used in modules. diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index ef0ae8a..64498d5 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -88,6 +88,7 @@ acpi_evaluate_dsm_typed(acpi_handle handle, const u8 *uuid, u64 rev, u64 func, } bool acpi_dev_found(const char *hid); +bool acpi_dev_present(const char *hid, const char *uid, int hrv); #ifdef CONFIG_ACPI diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 9b05886..e5dd0f1 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -611,6 +611,11 @@ static inline bool acpi_dev_found(const char *hid) return false; } +static inline bool acpi_dev_present(const char *hid, const char *uid, int hrv) +{ + return false; +} + static inline bool is_acpi_node(struct fwnode_handle *fwnode) { return false;