265 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Toshiba HDD Active Protection Sensor (HAPS) driver4 *5 * Copyright (C) 2014 Azael Avalos <coproscefalo@gmail.com>6 */7 8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt9 10#include <linux/kernel.h>11#include <linux/module.h>12#include <linux/init.h>13#include <linux/types.h>14#include <linux/acpi.h>15 16MODULE_AUTHOR("Azael Avalos <coproscefalo@gmail.com>");17MODULE_DESCRIPTION("Toshiba HDD Active Protection Sensor");18MODULE_LICENSE("GPL");19 20struct toshiba_haps_dev {21 struct acpi_device *acpi_dev;22 23 int protection_level;24};25 26static struct toshiba_haps_dev *toshiba_haps;27 28/* HAPS functions */29static int toshiba_haps_reset_protection(acpi_handle handle)30{31 acpi_status status;32 33 status = acpi_evaluate_object(handle, "RSSS", NULL, NULL);34 if (ACPI_FAILURE(status)) {35 pr_err("Unable to reset the HDD protection\n");36 return -EIO;37 }38 39 return 0;40}41 42static int toshiba_haps_protection_level(acpi_handle handle, int level)43{44 acpi_status status;45 46 status = acpi_execute_simple_method(handle, "PTLV", level);47 if (ACPI_FAILURE(status)) {48 pr_err("Error while setting the protection level\n");49 return -EIO;50 }51 52 pr_debug("HDD protection level set to: %d\n", level);53 54 return 0;55}56 57/* sysfs files */58static ssize_t protection_level_show(struct device *dev,59 struct device_attribute *attr, char *buf)60{61 struct toshiba_haps_dev *haps = dev_get_drvdata(dev);62 63 return sprintf(buf, "%i\n", haps->protection_level);64}65 66static ssize_t protection_level_store(struct device *dev,67 struct device_attribute *attr,68 const char *buf, size_t count)69{70 struct toshiba_haps_dev *haps = dev_get_drvdata(dev);71 int level;72 int ret;73 74 ret = kstrtoint(buf, 0, &level);75 if (ret)76 return ret;77 /*78 * Check for supported levels, which can be:79 * 0 - Disabled | 1 - Low | 2 - Medium | 3 - High80 */81 if (level < 0 || level > 3)82 return -EINVAL;83 84 /* Set the sensor level */85 ret = toshiba_haps_protection_level(haps->acpi_dev->handle, level);86 if (ret != 0)87 return ret;88 89 haps->protection_level = level;90 91 return count;92}93static DEVICE_ATTR_RW(protection_level);94 95static ssize_t reset_protection_store(struct device *dev,96 struct device_attribute *attr,97 const char *buf, size_t count)98{99 struct toshiba_haps_dev *haps = dev_get_drvdata(dev);100 int reset;101 int ret;102 103 ret = kstrtoint(buf, 0, &reset);104 if (ret)105 return ret;106 /* The only accepted value is 1 */107 if (reset != 1)108 return -EINVAL;109 110 /* Reset the protection interface */111 ret = toshiba_haps_reset_protection(haps->acpi_dev->handle);112 if (ret != 0)113 return ret;114 115 return count;116}117static DEVICE_ATTR_WO(reset_protection);118 119static struct attribute *haps_attributes[] = {120 &dev_attr_protection_level.attr,121 &dev_attr_reset_protection.attr,122 NULL,123};124 125static const struct attribute_group haps_attr_group = {126 .attrs = haps_attributes,127};128 129/*130 * ACPI stuff131 */132static void toshiba_haps_notify(struct acpi_device *device, u32 event)133{134 pr_debug("Received event: 0x%x\n", event);135 136 acpi_bus_generate_netlink_event(device->pnp.device_class,137 dev_name(&device->dev),138 event, 0);139}140 141static void toshiba_haps_remove(struct acpi_device *device)142{143 sysfs_remove_group(&device->dev.kobj, &haps_attr_group);144 145 if (toshiba_haps)146 toshiba_haps = NULL;147}148 149/* Helper function */150static int toshiba_haps_available(acpi_handle handle)151{152 acpi_status status;153 u64 hdd_present;154 155 /*156 * A non existent device as well as having (only)157 * Solid State Drives can cause the call to fail.158 */159 status = acpi_evaluate_integer(handle, "_STA", NULL, &hdd_present);160 if (ACPI_FAILURE(status)) {161 pr_err("ACPI call to query HDD protection failed\n");162 return 0;163 }164 165 if (!hdd_present) {166 pr_info("HDD protection not available or using SSD\n");167 return 0;168 }169 170 return 1;171}172 173static int toshiba_haps_add(struct acpi_device *acpi_dev)174{175 struct toshiba_haps_dev *haps;176 int ret;177 178 if (toshiba_haps)179 return -EBUSY;180 181 if (!toshiba_haps_available(acpi_dev->handle))182 return -ENODEV;183 184 pr_info("Toshiba HDD Active Protection Sensor device\n");185 186 haps = kzalloc(sizeof(struct toshiba_haps_dev), GFP_KERNEL);187 if (!haps)188 return -ENOMEM;189 190 haps->acpi_dev = acpi_dev;191 haps->protection_level = 2;192 acpi_dev->driver_data = haps;193 dev_set_drvdata(&acpi_dev->dev, haps);194 195 /* Set the protection level, currently at level 2 (Medium) */196 ret = toshiba_haps_protection_level(acpi_dev->handle, 2);197 if (ret != 0)198 return ret;199 200 ret = sysfs_create_group(&acpi_dev->dev.kobj, &haps_attr_group);201 if (ret)202 return ret;203 204 toshiba_haps = haps;205 206 return 0;207}208 209#ifdef CONFIG_PM_SLEEP210static int toshiba_haps_suspend(struct device *device)211{212 struct toshiba_haps_dev *haps;213 int ret;214 215 haps = acpi_driver_data(to_acpi_device(device));216 217 /* Deactivate the protection on suspend */218 ret = toshiba_haps_protection_level(haps->acpi_dev->handle, 0);219 220 return ret;221}222 223static int toshiba_haps_resume(struct device *device)224{225 struct toshiba_haps_dev *haps;226 int ret;227 228 haps = acpi_driver_data(to_acpi_device(device));229 230 /* Set the stored protection level */231 ret = toshiba_haps_protection_level(haps->acpi_dev->handle,232 haps->protection_level);233 234 /* Reset the protection on resume */235 ret = toshiba_haps_reset_protection(haps->acpi_dev->handle);236 if (ret != 0)237 return ret;238 239 return ret;240}241#endif242 243static SIMPLE_DEV_PM_OPS(toshiba_haps_pm,244 toshiba_haps_suspend, toshiba_haps_resume);245 246static const struct acpi_device_id haps_device_ids[] = {247 {"TOS620A", 0},248 {"", 0},249};250MODULE_DEVICE_TABLE(acpi, haps_device_ids);251 252static struct acpi_driver toshiba_haps_driver = {253 .name = "Toshiba HAPS",254 .ids = haps_device_ids,255 .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,256 .ops = {257 .add = toshiba_haps_add,258 .remove = toshiba_haps_remove,259 .notify = toshiba_haps_notify,260 },261 .drv.pm = &toshiba_haps_pm,262};263 264module_acpi_driver(toshiba_haps_driver);265