1 /* 2 * HID over I2C ACPI Subclass 3 * 4 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com> 5 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France 6 * Copyright (c) 2012 Red Hat, Inc 7 * 8 * This code was forked out of the core code, which was partly based on 9 * "USB HID support for Linux": 10 * 11 * Copyright (c) 1999 Andreas Gal 12 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz> 13 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc 14 * Copyright (c) 2007-2008 Oliver Neukum 15 * Copyright (c) 2006-2010 Jiri Kosina 16 * 17 * This file is subject to the terms and conditions of the GNU General Public 18 * License. See the file COPYING in the main directory of this archive for 19 * more details. 20 */ 21 22 #include <linux/acpi.h> 23 #include <linux/device.h> 24 #include <linux/i2c.h> 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/pm.h> 28 29 #include "i2c-hid.h" 30 31 struct i2c_hid_acpi { 32 struct i2chid_ops ops; 33 struct i2c_client *client; 34 }; 35 36 static const struct acpi_device_id i2c_hid_acpi_blacklist[] = { 37 /* 38 * The CHPN0001 ACPI device, which is used to describe the Chipone 39 * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible. 40 */ 41 {"CHPN0001", 0 }, 42 { }, 43 }; 44 45 static int i2c_hid_acpi_get_descriptor(struct i2c_client *client) 46 { 47 static guid_t i2c_hid_guid = 48 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555, 49 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE); 50 union acpi_object *obj; 51 struct acpi_device *adev; 52 acpi_handle handle; 53 u16 hid_descriptor_address; 54 55 handle = ACPI_HANDLE(&client->dev); 56 if (!handle || acpi_bus_get_device(handle, &adev)) { 57 dev_err(&client->dev, "Error could not get ACPI device\n"); 58 return -ENODEV; 59 } 60 61 if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0) 62 return -ENODEV; 63 64 obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL, 65 ACPI_TYPE_INTEGER); 66 if (!obj) { 67 dev_err(&client->dev, "Error _DSM call to get HID descriptor address failed\n"); 68 return -ENODEV; 69 } 70 71 hid_descriptor_address = obj->integer.value; 72 ACPI_FREE(obj); 73 74 return hid_descriptor_address; 75 } 76 77 static void i2c_hid_acpi_shutdown_tail(struct i2chid_ops *ops) 78 { 79 struct i2c_hid_acpi *ihid_acpi = 80 container_of(ops, struct i2c_hid_acpi, ops); 81 struct device *dev = &ihid_acpi->client->dev; 82 acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D3_COLD); 83 } 84 85 static int i2c_hid_acpi_probe(struct i2c_client *client, 86 const struct i2c_device_id *dev_id) 87 { 88 struct device *dev = &client->dev; 89 struct i2c_hid_acpi *ihid_acpi; 90 struct acpi_device *adev; 91 u16 hid_descriptor_address; 92 int ret; 93 94 ihid_acpi = devm_kzalloc(&client->dev, sizeof(*ihid_acpi), GFP_KERNEL); 95 if (!ihid_acpi) 96 return -ENOMEM; 97 98 ihid_acpi->client = client; 99 ihid_acpi->ops.shutdown_tail = i2c_hid_acpi_shutdown_tail; 100 101 ret = i2c_hid_acpi_get_descriptor(client); 102 if (ret < 0) 103 return ret; 104 hid_descriptor_address = ret; 105 106 adev = ACPI_COMPANION(dev); 107 if (adev) 108 acpi_device_fix_up_power(adev); 109 110 if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) { 111 device_set_wakeup_capable(dev, true); 112 device_set_wakeup_enable(dev, false); 113 } 114 115 return i2c_hid_core_probe(client, &ihid_acpi->ops, 116 hid_descriptor_address); 117 } 118 119 static const struct acpi_device_id i2c_hid_acpi_match[] = { 120 {"ACPI0C50", 0 }, 121 {"PNP0C50", 0 }, 122 { }, 123 }; 124 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match); 125 126 static struct i2c_driver i2c_hid_acpi_driver = { 127 .driver = { 128 .name = "i2c_hid_acpi", 129 .pm = &i2c_hid_core_pm, 130 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 131 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match), 132 }, 133 134 .probe = i2c_hid_acpi_probe, 135 .remove = i2c_hid_core_remove, 136 .shutdown = i2c_hid_core_shutdown, 137 }; 138 139 module_i2c_driver(i2c_hid_acpi_driver); 140 141 MODULE_DESCRIPTION("HID over I2C ACPI driver"); 142 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>"); 143 MODULE_LICENSE("GPL"); 144