From patchwork Wed Apr 26 21:24:12 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 9702079 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 5978B603F4 for ; Wed, 26 Apr 2017 21:35:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 48F5D285E7 for ; Wed, 26 Apr 2017 21:35:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3DC4F285EE; Wed, 26 Apr 2017 21:35:09 +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=unavailable 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 75220285E7 for ; Wed, 26 Apr 2017 21:35:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030668AbdDZVeS (ORCPT ); Wed, 26 Apr 2017 17:34:18 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:47149 "EHLO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030581AbdDZVdn (ORCPT ); Wed, 26 Apr 2017 17:33:43 -0400 Received: from 79.184.252.54.ipv4.supernova.orange.pl (79.184.252.54) (HELO aspire.rjw.lan) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.82) id 015494cbdb827e22; Wed, 26 Apr 2017 23:33:43 +0200 From: "Rafael J. Wysocki" To: Linux PM Cc: Andy Shevchenko , Darren Hart , LKML , Linux ACPI , Srinivas Pandruvada , Thomas Gleixner , Mika Westerberg , Mario Limonciello Subject: [PATCH 3/5] ACPI / sleep: EC-based wakeup from suspend-to-idle on Dell systems Date: Wed, 26 Apr 2017 23:24:12 +0200 Message-ID: <3060629.nj3VExRueE@aspire.rjw.lan> User-Agent: KMail/4.14.10 (Linux/4.11.0-rc6+; KDE/4.14.9; x86_64; ; ) In-Reply-To: <1979543.KIEJ8uyRaT@aspire.rjw.lan> References: <1979543.KIEJ8uyRaT@aspire.rjw.lan> MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Rafael J. Wysocki Some recent Dell laptops, including the XPS13 model numbers 9360 and 9365, cannot be woken up from suspend-to-idle by pressing the power button which is unexpected and makes that feature hardly usable on those systems. However, on the 9365 ACPI S3 (suspend-to-RAM) is not expected to be used at all (these systems ship with Windows 10 using Modern Standby which never exercises the ACPI S3 path) and suspend-to-idle is the only viable system suspend mechanism in there. The reason why the power button wakeup from suspend-to-idle doesn't work on those systems is because their power button events are signaled by the EC (Embedded Controller), whose GPE (General Purpose Event) line is disabled during suspend-to-idle transitions in Linux. That is done on purpose, because in general the EC tends to generate tons of events for various reasons (battery and thermal updates and similar, for example) and all of them would kick the CPUs out of deep idle states while in suspend-to-idle, which would not be desirable. Of course, on the Dell systems in question the EC GPE must be enabled during suspend-to-idle transitions for the button press events to be signaled while suspended at all. Fortunately, there is a way to tell the EC to stop generating the non-wakeup events, which is by using the _DSM object under the so called micro-PEP (uPEP) device provided to support Modern Standby in Windows 10. The expected way to use it is to invoke function 0 from it on system initialization, functions 3 and 5 during suspend transitions and functions 4 and 6 during resume transitions (to reverse the actions carried out by the former). In particular, function 5 from the uPEP device _DSM causes the EC to become less verbose (so to speak) on the affected systems and then its GPE can be enabled as a wakeup source (then, on resume, function 6 switches it back to the "working state" mode). In support of the affected Dell systems, implement the uPEP device handling as described and allow the EC to generate system wakeup events if that device is present and behaves as expected. Enable that for Dell only, as there are other systems out there in which the uPEP device is exposed in the ACPI tables and its _DSM appears to be functional, but it actually isn't, whereas Dell is committed to supporting it. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/ec.c | 19 +++++++- drivers/acpi/internal.h | 2 drivers/acpi/sleep.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 130 insertions(+), 1 deletion(-) Index: linux-pm/drivers/acpi/ec.c =================================================================== --- linux-pm.orig/drivers/acpi/ec.c +++ linux-pm/drivers/acpi/ec.c @@ -40,6 +40,7 @@ #include #include #include +#include #include #include "internal.h" @@ -1493,6 +1494,16 @@ static int acpi_ec_setup(struct acpi_ec acpi_handle_info(ec->handle, "GPE=0x%lx, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->gpe, ec->command_addr, ec->data_addr); + + /* + * On some platforms the EC GPE is used for waking up the system from + * suspend-to-idle, so mark it as a wakeup one. + * + * This can be done unconditionally, as the setting does not matter + * until acpi_set_gpe_wake_mask() is called for the GPE. + */ + acpi_mark_gpe_for_wake(NULL, ec->gpe); + return ret; } @@ -1835,8 +1846,11 @@ static int acpi_ec_suspend(struct device struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); - if (ec_freeze_events) + if (!pm_suspend_via_firmware() && acpi_sleep_ec_gpe_may_wakeup()) + acpi_set_gpe_wake_mask(NULL, ec->gpe, ACPI_GPE_ENABLE); + else if (ec_freeze_events) acpi_ec_disable_event(ec); + return 0; } @@ -1846,6 +1860,9 @@ static int acpi_ec_resume(struct device acpi_driver_data(to_acpi_device(dev)); acpi_ec_enable_event(ec); + if (!pm_resume_via_firmware() && acpi_sleep_ec_gpe_may_wakeup()) + acpi_set_gpe_wake_mask(NULL, ec->gpe, ACPI_GPE_DISABLE); + return 0; } #endif Index: linux-pm/drivers/acpi/internal.h =================================================================== --- linux-pm.orig/drivers/acpi/internal.h +++ linux-pm/drivers/acpi/internal.h @@ -199,8 +199,10 @@ void acpi_ec_remove_query_handler(struct -------------------------------------------------------------------------- */ #ifdef CONFIG_ACPI_SYSTEM_POWER_STATES_SUPPORT extern int acpi_sleep_init(void); +bool acpi_sleep_ec_gpe_may_wakeup(void); #else static inline int acpi_sleep_init(void) { return -ENXIO; } +static inline bool acpi_sleep_ec_gpe_may_wakeup(void) { return false; } #endif #ifdef CONFIG_ACPI_SLEEP Index: linux-pm/drivers/acpi/sleep.c =================================================================== --- linux-pm.orig/drivers/acpi/sleep.c +++ linux-pm/drivers/acpi/sleep.c @@ -160,6 +160,10 @@ static int __init init_nvs_nosave(const return 0; } +#ifdef CONFIG_SUSPEND +static int __init init_upep_device(const struct dmi_system_id *d); +#endif + static struct dmi_system_id acpisleep_dmi_table[] __initdata = { { .callback = init_old_suspend_ordering, @@ -343,6 +347,15 @@ static struct dmi_system_id acpisleep_dm DMI_MATCH(DMI_PRODUCT_NAME, "80E3"), }, }, +#ifdef CONFIG_SUSPEND + { + .callback = init_upep_device, + .ident = "All Dell systems", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + }, + }, +#endif {}, }; @@ -649,6 +662,94 @@ static const struct platform_suspend_ops .recover = acpi_pm_finish, }; +/* + * The micro-PEP (uPEP) device object is exposed in ACPI tables on systems + * supporting Windows 10 with Modern Standby. The _DSM object under it, if + * present, can be used to indicate to the platform that the OS is transitioning + * into a low-power state in which certain types of activity are not desirable. + */ +static acpi_handle upep_device_handle; + +#define ACPI_S2IDLE_SCREEN_OFF 3 +#define ACPI_S2IDLE_SCREEN_ON 4 +#define ACPI_S2IDLE_IR_ENTRY 5 +#define ACPI_S2IDLE_IR_EXIT 6 + +#define ACPI_S2IDLE_DSM_MASK ((1 << ACPI_S2IDLE_IR_ENTRY) | (1 << ACPI_S2IDLE_IR_EXIT)) + +static char upep_dsm_func_mask; + +/* uPEP device _DSM UUID: c4eb40a0-6cd2-11e2-bcfd-0800200c9a66 */ +static const u8 upep_dsm_uuid[16] = { + 0xa0, 0x40, 0xeb, 0xc4, 0xd2, 0x6c, 0xe2, 0x11, + 0xbc, 0xfd, 0x08, 0x00, 0x20, 0x0c, 0x9a, 0x66 +}; + +static void acpi_sleep_call_upep_dsm(unsigned int func) +{ + union acpi_object *out_obj; + + if (!(upep_dsm_func_mask & (1 << func))) + return; + + out_obj = acpi_evaluate_dsm(upep_device_handle, upep_dsm_uuid, 1, func, + NULL); + ACPI_FREE(out_obj); + + acpi_handle_debug(upep_device_handle, "_DSM function %u evaluation %s\n", + func, out_obj ? "successful" : "failed"); +} + +static int upep_device_attach(struct acpi_device *adev, + const struct acpi_device_id *not_used) +{ + union acpi_object *out_obj; + + if (upep_device_handle) + return 0; + + /* Check if the _DSM is present and as expected. */ + out_obj = acpi_evaluate_dsm(adev->handle, upep_dsm_uuid, 1, 0, NULL); + if (out_obj && out_obj->type == ACPI_TYPE_BUFFER) { + char bitmask = *(char *)out_obj->buffer.pointer; + + if (bitmask & ACPI_S2IDLE_DSM_MASK) { + upep_dsm_func_mask = bitmask; + upep_device_handle = adev->handle; + } + + acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n", + bitmask); + } else { + acpi_handle_debug(adev->handle, + "_DSM function 0 evaluation failed\n"); + } + ACPI_FREE(out_obj); + return 0; +} + +static const struct acpi_device_id upep_device_ids[] = { + {"INT33A1", }, + {"PNP0D80", }, + {"", }, +}; + +static struct acpi_scan_handler upep_handler = { + .ids = upep_device_ids, + .attach = upep_device_attach, +}; + +static int __init init_upep_device(const struct dmi_system_id *d) +{ + acpi_scan_add_handler(&upep_handler); + return 0; +} + +bool acpi_sleep_ec_gpe_may_wakeup(void) +{ + return !!upep_device_handle; +} + static int acpi_freeze_begin(void) { acpi_scan_lock_acquire(); @@ -657,6 +758,8 @@ static int acpi_freeze_begin(void) static int acpi_freeze_prepare(void) { + acpi_sleep_call_upep_dsm(ACPI_S2IDLE_SCREEN_OFF); + acpi_sleep_call_upep_dsm(ACPI_S2IDLE_IR_ENTRY); acpi_enable_wakeup_devices(ACPI_STATE_S0); acpi_enable_all_wakeup_gpes(); acpi_enable_all_runtime_gpes(); @@ -698,6 +801,8 @@ static void acpi_freeze_restore(void) disable_irq_wake(acpi_sci_irq); acpi_enable_all_runtime_gpes(); + acpi_sleep_call_upep_dsm(ACPI_S2IDLE_IR_EXIT); + acpi_sleep_call_upep_dsm(ACPI_S2IDLE_SCREEN_ON); } static void acpi_freeze_end(void) @@ -729,6 +834,11 @@ static void acpi_sleep_suspend_setup(voi #else /* !CONFIG_SUSPEND */ static inline void acpi_sleep_suspend_setup(void) {} + +bool acpi_sleep_ec_gpe_may_wakeup(void) +{ + return false; +} #endif /* !CONFIG_SUSPEND */ #ifdef CONFIG_PM_SLEEP