From patchwork Wed Jun 28 17:20:19 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 9814939 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 E5AC560383 for ; Wed, 28 Jun 2017 17:41:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CE6662860D for ; Wed, 28 Jun 2017 17:41:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C302228638; Wed, 28 Jun 2017 17:41:14 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C6FA028634 for ; Wed, 28 Jun 2017 17:41:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751574AbdF1RlN (ORCPT ); Wed, 28 Jun 2017 13:41:13 -0400 Received: from mailout2.hostsharing.net ([83.223.90.233]:35993 "EHLO mailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751521AbdF1RlL (ORCPT ); Wed, 28 Jun 2017 13:41:11 -0400 Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mailout2.hostsharing.net (Postfix) with ESMTPS id ED9BB10354F2D; Wed, 28 Jun 2017 19:41:05 +0200 (CEST) Received: from localhost (5-38-90-81.adsl.cmo.de [81.90.38.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id 7CB6E61BAB78; Wed, 28 Jun 2017 19:41:06 +0200 (CEST) X-Mailbox-Line: From e72ce423489dd604ae98ad3b76e07caf944cb581 Mon Sep 17 00:00:00 2001 Message-Id: In-Reply-To: References: From: Lukas Wunner Date: Wed, 28 Jun 2017 19:20:19 +0200 Subject: [PATCH v2 2/4] ACPI / property: Support Apple _DSM properties MIME-Version: 1.0 To: "Rafael J. Wysocki" , Mark Brown , Ronald Tschalaer , Federico Lorenzi Cc: Mika Westerberg , Andy Shevchenko , Leif Liddy , Daniel Roschka , linux-acpi@vger.kernel.org, linux-spi@vger.kernel.org Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP While the rest of the world has standardized on _DSD as the way to store device properties in AML (introduced with ACPI 5.1 in 2014), Apple has been using a custom _DSM to achieve the same for much longer (ever since they switched from DeviceTree-based PowerPC to Intel in 2005, verified with MacOS X 10.4.11). The theory of operation on macOS is as follows: AppleACPIPlatform.kext invokes mergeEFIproperties() and mergeDSMproperties() for each device to merge properties conveyed by EFI drivers as well as properties stored in AML into the I/O Kit registry from which they can be retrieved by drivers. We've been supporting EFI properties since commit 58c5475aba67 ("x86/efi: Retrieve and assign Apple device properties"). The present commit adds support for _DSM properties, thereby completing our support for Apple device properties. The _DSM properties are made available under the primary fwnode, the EFI properties under the secondary fwnode. So for devices which possess both property types, they can all be elegantly accessed with the uniform API in . Until recently we had no need to support _DSM properties, they contained only uninteresting garbage. The situation has changed with MacBooks and MacBook Pros introduced since 2015: Their keyboard is attached with SPI instead of USB and the _CRS data which is necessary to initialize the spi driver only contains valid information if OSPM responds "false" to _OSI("Darwin"). If OSPM responds "true", _CRS is empty and the spi driver fails to initialize. The rationale is very simple, Apple only cares about macOS and Windows: On Windows, _CRS contains valid data, whereas on macOS it is empty. Instead, macOS gleans the necessary data from the _DSM properties. Since Linux deliberately defaults to responding "true" to _OSI("Darwin"), we need to emulate macOS' behaviour by initializing the spi driver with data returned by the _DSM. An out-of-tree driver for the SPI keyboard exists which currently binds to the ACPI device, invokes the _DSM, parses the returned package and instantiates an SPI device with the data gleaned from the _DSM: https://github.com/cb22/macbook12-spi-driver/commit/9a416d699ef4 https://github.com/cb22/macbook12-spi-driver/commit/0c34936ed9a1 By adding support for Apple's _DSM properties in generic ACPI code, the out-of-tree driver will be able to register as a regular SPI device, significantly reducing its amount of code and improving its chances to be mainlined. The SPI keyboard will not be the only user of this commit: E.g. on the MacBook8,1, the UART-attached Bluetooth device likewise returns empty _CRS data if OSPM returns "true" to _OSI("Darwin"). The _DSM returns a Package whose format unfortunately deviates slightly from the _DSD spec: The properties are marshalled up in a single Package as alternating key/value elements, unlike _DSD which stores them as a Package of 2-element Packages. The present commit therefore converts the Package to _DSD format and the ACPI core can then treat the data as if Apple would follow the standard. Well, except for one small annoyance: The properties returned by the _DSM only ever have one of two types, Integer or Buffer. The former is retrievable as usual with device_property_read_u64(), but the latter is not part of the _DSD spec and it is not possible to retrieve Buffer properties with the device_property_read_*() functions due to the type checking performed in drivers/acpi/property.c. It is however possible to retrieve them with acpi_dev_get_property(). Apple is using the Buffer type somewhat sloppily to store null-terminated strings but also integers. The real data type is not distinguishable by the ACPI core and the onus is on the caller to use the contents of the Buffer in an appropriate way. In case Apple moves to _DSD in the future, this commit first checks for _DSD and falls back to _DSM only if _DSD is not found. Cc: Rafael J. Wysocki Cc: Mika Westerberg Cc: Andy Shevchenko Cc: Federico Lorenzi Tested-by: Ronald Tschalär Signed-off-by: Lukas Wunner Acked-by: Mika Westerberg --- Changes v1 -> v2: - Rebase on uuid-types branch. (Andy, Rafael) - Don't align assignments. (Mika) - Move IS_ENABLED() and dmi_match() conditionals into callee. (Mika) - Tone down messages indicating an unsupported properties version or illegal property type to KERN_INFO to avoid scaring or annoying users who may see it on every boot despite "quiet", but still allowing diagnosis of issues that may ensue. (Mika) drivers/acpi/property.c | 123 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index 116bfc1937b5..6a56f3a85f18 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -15,7 +15,9 @@ #include #include +#include #include +#include #include "internal.h" @@ -34,6 +36,124 @@ static const u8 ads_uuid[16] = { 0xe6, 0xe3, 0xb8, 0xdb, 0x86, 0x58, 0xa6, 0x4b, 0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b }; +/* Apple _DSM device properties GUID */ +static const guid_t apple_prp_guid = + GUID_INIT(0xA0B5B7C6, 0x1318, 0x441C, + 0xB0, 0xC9, 0xFE, 0x69, 0x5E, 0xAF, 0x94, 0x9B); + +/** + * acpi_retrieve_apple_properties - retrieve and convert Apple _DSM properties + * @adev: ACPI device for which to retrieve the properties + * + * Invoke Apple's custom _DSM once to check the protocol version and once more + * to retrieve the properties. They are marshalled up in a single package as + * alternating key/value elements, unlike _DSD which stores them as a package + * of 2-element packages. Convert to _DSD format and make them available under + * the primary fwnode. + */ +static void acpi_retrieve_apple_properties(struct acpi_device *adev) +{ + unsigned int i, j, newsize = 0, numprops, skipped = 0; + union acpi_object *props, *newprops; + void *free_space; + + if (!IS_ENABLED(CONFIG_X86) || !dmi_match(DMI_SYS_VENDOR, "Apple Inc.")) + return; + + props = acpi_evaluate_dsm_typed(adev->handle, &apple_prp_guid, 1, 0, + NULL, ACPI_TYPE_BUFFER); + if (!props) + return; + + if (!props->buffer.length || props->buffer.pointer[0] != 3) { + acpi_handle_info(adev->handle, FW_INFO + "unsupported properties version %*ph\n", + props->buffer.length, props->buffer.pointer); + goto out_free; + } + + ACPI_FREE(props); + props = acpi_evaluate_dsm_typed(adev->handle, &apple_prp_guid, 1, 1, + NULL, ACPI_TYPE_PACKAGE); + if (!props) + return; + + /* newsize = key length + value length of each tuple */ + numprops = props->package.count / 2; + for (i = 0; i < numprops; i++) { + union acpi_object *key = &props->package.elements[i * 2]; + union acpi_object *val = &props->package.elements[i * 2 + 1]; + + if ( key->type != ACPI_TYPE_STRING || + (val->type != ACPI_TYPE_INTEGER && + val->type != ACPI_TYPE_BUFFER)) { + key->type = ACPI_TYPE_ANY; /* mark as to be skipped */ + skipped++; + continue; + } + newsize += key->string.length + 1; + if ( val->type == ACPI_TYPE_BUFFER) + newsize += val->buffer.length; + } + + if (skipped) + acpi_handle_info(adev->handle, FW_INFO + "skipped %u properties: wrong type\n", + skipped); + if (skipped == numprops) + goto out_free; + + /* newsize += top-level package + 3 objects for each key/value tuple */ + newsize += (1 + 3 * (numprops - skipped)) * sizeof(union acpi_object); + newprops = ACPI_ALLOCATE_ZEROED(newsize); + if (!newprops) + goto out_free; + + /* layout: top-level package | packages | key/value tuples | strings */ + newprops->type = ACPI_TYPE_PACKAGE; + newprops->package.count = numprops - skipped; + newprops->package.elements = &newprops[1]; + free_space = &newprops[1 + 3 * (numprops - skipped)]; + + for (i = 0, j = 0; i < numprops; i++) { + union acpi_object *key = &props->package.elements[i * 2]; + union acpi_object *val = &props->package.elements[i * 2 + 1]; + unsigned int k = (1 + numprops - skipped) + j * 2; + unsigned int v = k + 1; /* index into newprops */ + + if (key->type == ACPI_TYPE_ANY) + continue; /* skipped */ + + newprops[1 + j].type = ACPI_TYPE_PACKAGE; + newprops[1 + j].package.count = 2; + newprops[1 + j].package.elements = &newprops[k]; + + newprops[k].type = ACPI_TYPE_STRING; + newprops[k].string.length = key->string.length; + newprops[k].string.pointer = free_space; + memcpy(free_space, key->string.pointer, key->string.length); + free_space += key->string.length + 1; + + newprops[v].type = val->type; + if (val->type == ACPI_TYPE_INTEGER) + newprops[v].integer.value = val->integer.value; + else { + newprops[v].buffer.length = val->buffer.length; + newprops[v].buffer.pointer = free_space; + memcpy(free_space, val->buffer.pointer, + val->buffer.length); + free_space += val->buffer.length; + } + j++; /* not incremented for skipped properties */ + } + WARN_ON(free_space != (void *)newprops + newsize); + + adev->data.properties = newprops; + adev->data.pointer = newprops; + +out_free: + ACPI_FREE(props); +} static bool acpi_enumerate_nondev_subnodes(acpi_handle scope, const union acpi_object *desc, @@ -376,6 +496,9 @@ void acpi_init_properties(struct acpi_device *adev) if (acpi_of && !adev->flags.of_compatible_ok) acpi_handle_info(adev->handle, ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n"); + + if (!adev->data.pointer) + acpi_retrieve_apple_properties(adev); } static void acpi_destroy_nondev_subnodes(struct list_head *list)