1 /* 2 * X86 ACPI Utility Functions 3 * 4 * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com> 5 * 6 * Based on various non upstream patches to support the CHT Whiskey Cove PMIC: 7 * Copyright (C) 2013-2015 Intel Corporation. All rights reserved. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 */ 13 14 #include <linux/acpi.h> 15 #include <asm/cpu_device_id.h> 16 #include <asm/intel-family.h> 17 #include "../internal.h" 18 19 /* 20 * Some ACPI devices are hidden (status == 0x0) in recent BIOS-es because 21 * some recent Windows drivers bind to one device but poke at multiple 22 * devices at the same time, so the others get hidden. 23 * We work around this by always reporting ACPI_STA_DEFAULT for these 24 * devices. Note this MUST only be done for devices where this is safe. 25 * 26 * This forcing of devices to be present is limited to specific CPU (SoC) 27 * models both to avoid potentially causing trouble on other models and 28 * because some HIDs are re-used on different SoCs for completely 29 * different devices. 30 */ 31 struct always_present_id { 32 struct acpi_device_id hid[2]; 33 struct x86_cpu_id cpu_ids[2]; 34 const char *uid; 35 }; 36 37 #define ICPU(model) { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, } 38 39 #define ENTRY(hid, uid, cpu_models) { \ 40 { { hid, }, {} }, \ 41 { cpu_models, {} }, \ 42 uid, \ 43 } 44 45 static const struct always_present_id always_present_ids[] = { 46 /* 47 * Bay / Cherry Trail PWM directly poked by GPU driver in win10, 48 * but Linux uses a separate PWM driver, harmless if not used. 49 */ 50 ENTRY("80860F09", "1", ICPU(INTEL_FAM6_ATOM_SILVERMONT1)), 51 ENTRY("80862288", "1", ICPU(INTEL_FAM6_ATOM_AIRMONT)), 52 /* 53 * The INT0002 device is necessary to clear wakeup interrupt sources 54 * on Cherry Trail devices, without it we get nobody cared IRQ msgs. 55 */ 56 ENTRY("INT0002", "1", ICPU(INTEL_FAM6_ATOM_AIRMONT)), 57 }; 58 59 bool acpi_device_always_present(struct acpi_device *adev) 60 { 61 u32 *status = (u32 *)&adev->status; 62 u32 old_status = *status; 63 bool ret = false; 64 unsigned int i; 65 66 /* acpi_match_device_ids checks status, so set it to default */ 67 *status = ACPI_STA_DEFAULT; 68 for (i = 0; i < ARRAY_SIZE(always_present_ids); i++) { 69 if (acpi_match_device_ids(adev, always_present_ids[i].hid)) 70 continue; 71 72 if (!adev->pnp.unique_id || 73 strcmp(adev->pnp.unique_id, always_present_ids[i].uid)) 74 continue; 75 76 if (!x86_match_cpu(always_present_ids[i].cpu_ids)) 77 continue; 78 79 if (old_status != ACPI_STA_DEFAULT) /* Log only once */ 80 dev_info(&adev->dev, 81 "Device [%s] is in always present list\n", 82 adev->pnp.bus_id); 83 84 ret = true; 85 break; 86 } 87 *status = old_status; 88 89 return ret; 90 } 91