projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| e04653a9 AP |
1 | /* |
| 2 | * ChromeOS EC multi-function device | |
| 3 | * | |
| 4 | * Copyright (C) 2017 Google, Inc | |
| 5 | * | |
| 6 | * This software is licensed under the terms of the GNU General Public | |
| 7 | * License version 2, as published by the Free Software Foundation, and | |
| 8 | * may be copied, distributed, and modified under those terms. | |
| 9 | * | |
| 10 | * This program is distributed in the hope that it will be useful, | |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 13 | * GNU General Public License for more details. | |
| 14 | * | |
| 15 | * The ChromeOS EC multi function device is used to mux all the requests | |
| 16 | * to the EC device for its multiple features: keyboard controller, | |
| 17 | * battery charging and regulator control, firmware update. | |
| 18 | */ | |
| 19 | #include <linux/acpi.h> | |
| 20 | ||
| 21 | #define ACPI_LID_DEVICE "LID0" | |
| 22 | ||
| 23 | static int ec_wake_gpe = -EINVAL; | |
| 24 | ||
| 25 | /* | |
| 26 | * This handler indicates to ACPI core that this GPE should stay enabled for | |
| 27 | * lid to work in suspend to idle path. | |
| 28 | */ | |
| 29 | static u32 cros_ec_gpe_handler(acpi_handle gpe_device, u32 gpe_number, | |
| 30 | void *data) | |
| 31 | { | |
| 32 | return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE; | |
| 33 | } | |
| 34 | ||
| 35 | /* | |
| 36 | * Get ACPI GPE for LID0 device. | |
| 37 | */ | |
| 38 | static int cros_ec_get_ec_wake_gpe(struct device *dev) | |
| 39 | { | |
| 40 | struct acpi_device *cros_acpi_dev; | |
| 41 | struct acpi_device *adev; | |
| 42 | acpi_handle handle; | |
| 43 | acpi_status status; | |
| 44 | int ret; | |
| 45 | ||
| 46 | cros_acpi_dev = ACPI_COMPANION(dev); | |
| 47 | ||
| 48 | if (!cros_acpi_dev || !cros_acpi_dev->parent || | |
| 49 | !cros_acpi_dev->parent->handle) | |
| 50 | return -EINVAL; | |
| 51 | ||
| 52 | status = acpi_get_handle(cros_acpi_dev->parent->handle, ACPI_LID_DEVICE, | |
| 53 | &handle); | |
| 54 | if (ACPI_FAILURE(status)) | |
| 55 | return -EINVAL; | |
| 56 | ||
| 57 | ret = acpi_bus_get_device(handle, &adev); | |
| 58 | if (ret) | |
| 59 | return ret; | |
| 60 | ||
| 61 | return adev->wakeup.gpe_number; | |
| 62 | } | |
| 63 | ||
| 64 | int cros_ec_acpi_install_gpe_handler(struct device *dev) | |
| 65 | { | |
| 66 | acpi_status status; | |
| 67 | ||
| 68 | ec_wake_gpe = cros_ec_get_ec_wake_gpe(dev); | |
| 69 | ||
| 70 | if (ec_wake_gpe < 0) | |
| 71 | return ec_wake_gpe; | |
| 72 | ||
| 73 | status = acpi_install_gpe_handler(NULL, ec_wake_gpe, | |
| 74 | ACPI_GPE_EDGE_TRIGGERED, | |
| 75 | &cros_ec_gpe_handler, NULL); | |
| 76 | if (ACPI_FAILURE(status)) | |
| 77 | return -ENODEV; | |
| 78 | ||
| 79 | dev_info(dev, "Initialized, GPE = 0x%x\n", ec_wake_gpe); | |
| 80 | ||
| 81 | return 0; | |
| 82 | } | |
| 83 | ||
| 84 | void cros_ec_acpi_remove_gpe_handler(void) | |
| 85 | { | |
| 86 | acpi_status status; | |
| 87 | ||
| 88 | if (ec_wake_gpe < 0) | |
| 89 | return; | |
| 90 | ||
| 91 | status = acpi_remove_gpe_handler(NULL, ec_wake_gpe, | |
| 92 | &cros_ec_gpe_handler); | |
| 93 | if (ACPI_FAILURE(status)) | |
| 94 | pr_err("failed to remove gpe handler\n"); | |
| 95 | } | |
| 96 | ||
| 97 | void cros_ec_acpi_clear_gpe(void) | |
| 98 | { | |
| 99 | if (ec_wake_gpe < 0) | |
| 100 | return; | |
| 101 | ||
| 102 | acpi_clear_gpe(NULL, ec_wake_gpe); | |
| 103 | } |