1 /* 2 * Toshiba HDD Active Protection Sensor (HAPS) driver 3 * 4 * Copyright (C) 2014 Azael Avalos <coproscefalo@gmail.com> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 */ 17 18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 19 20 #include <linux/kernel.h> 21 #include <linux/module.h> 22 #include <linux/init.h> 23 #include <linux/types.h> 24 #include <linux/acpi.h> 25 26 MODULE_AUTHOR("Azael Avalos <coproscefalo@gmail.com>"); 27 MODULE_DESCRIPTION("Toshiba HDD Active Protection Sensor"); 28 MODULE_LICENSE("GPL"); 29 30 struct toshiba_haps_dev { 31 struct acpi_device *acpi_dev; 32 33 int protection_level; 34 }; 35 36 static struct toshiba_haps_dev *toshiba_haps; 37 38 /* HAPS functions */ 39 static int toshiba_haps_reset_protection(acpi_handle handle) 40 { 41 acpi_status status; 42 43 status = acpi_evaluate_object(handle, "RSSS", NULL, NULL); 44 if (ACPI_FAILURE(status)) { 45 pr_err("Unable to reset the HDD protection\n"); 46 return -EIO; 47 } 48 49 return 0; 50 } 51 52 static int toshiba_haps_protection_level(acpi_handle handle, int level) 53 { 54 acpi_status status; 55 56 status = acpi_execute_simple_method(handle, "PTLV", level); 57 if (ACPI_FAILURE(status)) { 58 pr_err("Error while setting the protection level\n"); 59 return -EIO; 60 } 61 62 pr_debug("HDD protection level set to: %d\n", level); 63 64 return 0; 65 } 66 67 /* sysfs files */ 68 static ssize_t protection_level_show(struct device *dev, 69 struct device_attribute *attr, char *buf) 70 { 71 struct toshiba_haps_dev *haps = dev_get_drvdata(dev); 72 73 return sprintf(buf, "%i\n", haps->protection_level); 74 } 75 76 static ssize_t protection_level_store(struct device *dev, 77 struct device_attribute *attr, 78 const char *buf, size_t count) 79 { 80 struct toshiba_haps_dev *haps = dev_get_drvdata(dev); 81 int level; 82 int ret; 83 84 ret = kstrtoint(buf, 0, &level); 85 if (ret) 86 return ret; 87 /* 88 * Check for supported levels, which can be: 89 * 0 - Disabled | 1 - Low | 2 - Medium | 3 - High 90 */ 91 if (level < 0 || level > 3) 92 return -EINVAL; 93 94 /* Set the sensor level */ 95 ret = toshiba_haps_protection_level(haps->acpi_dev->handle, level); 96 if (ret != 0) 97 return ret; 98 99 haps->protection_level = level; 100 101 return count; 102 } 103 static DEVICE_ATTR_RW(protection_level); 104 105 static ssize_t reset_protection_store(struct device *dev, 106 struct device_attribute *attr, 107 const char *buf, size_t count) 108 { 109 struct toshiba_haps_dev *haps = dev_get_drvdata(dev); 110 int reset; 111 int ret; 112 113 ret = kstrtoint(buf, 0, &reset); 114 if (ret) 115 return ret; 116 /* The only accepted value is 1 */ 117 if (reset != 1) 118 return -EINVAL; 119 120 /* Reset the protection interface */ 121 ret = toshiba_haps_reset_protection(haps->acpi_dev->handle); 122 if (ret != 0) 123 return ret; 124 125 return count; 126 } 127 static DEVICE_ATTR_WO(reset_protection); 128 129 static struct attribute *haps_attributes[] = { 130 &dev_attr_protection_level.attr, 131 &dev_attr_reset_protection.attr, 132 NULL, 133 }; 134 135 static const struct attribute_group haps_attr_group = { 136 .attrs = haps_attributes, 137 }; 138 139 /* 140 * ACPI stuff 141 */ 142 static void toshiba_haps_notify(struct acpi_device *device, u32 event) 143 { 144 pr_debug("Received event: 0x%x", event); 145 146 acpi_bus_generate_netlink_event(device->pnp.device_class, 147 dev_name(&device->dev), 148 event, 0); 149 } 150 151 static int toshiba_haps_remove(struct acpi_device *device) 152 { 153 sysfs_remove_group(&device->dev.kobj, &haps_attr_group); 154 155 if (toshiba_haps) 156 toshiba_haps = NULL; 157 158 return 0; 159 } 160 161 /* Helper function */ 162 static int toshiba_haps_available(acpi_handle handle) 163 { 164 acpi_status status; 165 u64 hdd_present; 166 167 /* 168 * A non existent device as well as having (only) 169 * Solid State Drives can cause the call to fail. 170 */ 171 status = acpi_evaluate_integer(handle, "_STA", NULL, &hdd_present); 172 if (ACPI_FAILURE(status)) { 173 pr_err("ACPI call to query HDD protection failed\n"); 174 return 0; 175 } 176 177 if (!hdd_present) { 178 pr_info("HDD protection not available or using SSD\n"); 179 return 0; 180 } 181 182 return 1; 183 } 184 185 static int toshiba_haps_add(struct acpi_device *acpi_dev) 186 { 187 struct toshiba_haps_dev *haps; 188 int ret; 189 190 if (toshiba_haps) 191 return -EBUSY; 192 193 if (!toshiba_haps_available(acpi_dev->handle)) 194 return -ENODEV; 195 196 pr_info("Toshiba HDD Active Protection Sensor device\n"); 197 198 haps = kzalloc(sizeof(struct toshiba_haps_dev), GFP_KERNEL); 199 if (!haps) 200 return -ENOMEM; 201 202 haps->acpi_dev = acpi_dev; 203 haps->protection_level = 2; 204 acpi_dev->driver_data = haps; 205 dev_set_drvdata(&acpi_dev->dev, haps); 206 207 /* Set the protection level, currently at level 2 (Medium) */ 208 ret = toshiba_haps_protection_level(acpi_dev->handle, 2); 209 if (ret != 0) 210 return ret; 211 212 ret = sysfs_create_group(&acpi_dev->dev.kobj, &haps_attr_group); 213 if (ret) 214 return ret; 215 216 toshiba_haps = haps; 217 218 return 0; 219 } 220 221 #ifdef CONFIG_PM_SLEEP 222 static int toshiba_haps_suspend(struct device *device) 223 { 224 struct toshiba_haps_dev *haps; 225 int ret; 226 227 haps = acpi_driver_data(to_acpi_device(device)); 228 229 /* Deactivate the protection on suspend */ 230 ret = toshiba_haps_protection_level(haps->acpi_dev->handle, 0); 231 232 return ret; 233 } 234 235 static int toshiba_haps_resume(struct device *device) 236 { 237 struct toshiba_haps_dev *haps; 238 int ret; 239 240 haps = acpi_driver_data(to_acpi_device(device)); 241 242 /* Set the stored protection level */ 243 ret = toshiba_haps_protection_level(haps->acpi_dev->handle, 244 haps->protection_level); 245 246 /* Reset the protection on resume */ 247 ret = toshiba_haps_reset_protection(haps->acpi_dev->handle); 248 if (ret != 0) 249 return ret; 250 251 return ret; 252 } 253 #endif 254 255 static SIMPLE_DEV_PM_OPS(toshiba_haps_pm, 256 toshiba_haps_suspend, toshiba_haps_resume); 257 258 static const struct acpi_device_id haps_device_ids[] = { 259 {"TOS620A", 0}, 260 {"", 0}, 261 }; 262 MODULE_DEVICE_TABLE(acpi, haps_device_ids); 263 264 static struct acpi_driver toshiba_haps_driver = { 265 .name = "Toshiba HAPS", 266 .owner = THIS_MODULE, 267 .ids = haps_device_ids, 268 .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS, 269 .ops = { 270 .add = toshiba_haps_add, 271 .remove = toshiba_haps_remove, 272 .notify = toshiba_haps_notify, 273 }, 274 .drv.pm = &toshiba_haps_pm, 275 }; 276 277 module_acpi_driver(toshiba_haps_driver); 278