treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
[sfrench/cifs-2.6.git] / drivers / platform / x86 / toshiba_haps.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Toshiba HDD Active Protection Sensor (HAPS) driver
4  *
5  * Copyright (C) 2014 Azael Avalos <coproscefalo@gmail.com>
6  */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
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
16 MODULE_AUTHOR("Azael Avalos <coproscefalo@gmail.com>");
17 MODULE_DESCRIPTION("Toshiba HDD Active Protection Sensor");
18 MODULE_LICENSE("GPL");
19
20 struct toshiba_haps_dev {
21         struct acpi_device *acpi_dev;
22
23         int protection_level;
24 };
25
26 static struct toshiba_haps_dev *toshiba_haps;
27
28 /* HAPS functions */
29 static 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
42 static 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 */
58 static 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
66 static 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 - High
80          */
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 }
93 static DEVICE_ATTR_RW(protection_level);
94
95 static 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 }
117 static DEVICE_ATTR_WO(reset_protection);
118
119 static struct attribute *haps_attributes[] = {
120         &dev_attr_protection_level.attr,
121         &dev_attr_reset_protection.attr,
122         NULL,
123 };
124
125 static const struct attribute_group haps_attr_group = {
126         .attrs = haps_attributes,
127 };
128
129 /*
130  * ACPI stuff
131  */
132 static void toshiba_haps_notify(struct acpi_device *device, u32 event)
133 {
134         pr_debug("Received event: 0x%x", event);
135
136         acpi_bus_generate_netlink_event(device->pnp.device_class,
137                                         dev_name(&device->dev),
138                                         event, 0);
139 }
140
141 static int 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         return 0;
149 }
150
151 /* Helper function */
152 static int toshiba_haps_available(acpi_handle handle)
153 {
154         acpi_status status;
155         u64 hdd_present;
156
157         /*
158          * A non existent device as well as having (only)
159          * Solid State Drives can cause the call to fail.
160          */
161         status = acpi_evaluate_integer(handle, "_STA", NULL, &hdd_present);
162         if (ACPI_FAILURE(status)) {
163                 pr_err("ACPI call to query HDD protection failed\n");
164                 return 0;
165         }
166
167         if (!hdd_present) {
168                 pr_info("HDD protection not available or using SSD\n");
169                 return 0;
170         }
171
172         return 1;
173 }
174
175 static int toshiba_haps_add(struct acpi_device *acpi_dev)
176 {
177         struct toshiba_haps_dev *haps;
178         int ret;
179
180         if (toshiba_haps)
181                 return -EBUSY;
182
183         if (!toshiba_haps_available(acpi_dev->handle))
184                 return -ENODEV;
185
186         pr_info("Toshiba HDD Active Protection Sensor device\n");
187
188         haps = kzalloc(sizeof(struct toshiba_haps_dev), GFP_KERNEL);
189         if (!haps)
190                 return -ENOMEM;
191
192         haps->acpi_dev = acpi_dev;
193         haps->protection_level = 2;
194         acpi_dev->driver_data = haps;
195         dev_set_drvdata(&acpi_dev->dev, haps);
196
197         /* Set the protection level, currently at level 2 (Medium) */
198         ret = toshiba_haps_protection_level(acpi_dev->handle, 2);
199         if (ret != 0)
200                 return ret;
201
202         ret = sysfs_create_group(&acpi_dev->dev.kobj, &haps_attr_group);
203         if (ret)
204                 return ret;
205
206         toshiba_haps = haps;
207
208         return 0;
209 }
210
211 #ifdef CONFIG_PM_SLEEP
212 static int toshiba_haps_suspend(struct device *device)
213 {
214         struct toshiba_haps_dev *haps;
215         int ret;
216
217         haps = acpi_driver_data(to_acpi_device(device));
218
219         /* Deactivate the protection on suspend */
220         ret = toshiba_haps_protection_level(haps->acpi_dev->handle, 0);
221
222         return ret;
223 }
224
225 static int toshiba_haps_resume(struct device *device)
226 {
227         struct toshiba_haps_dev *haps;
228         int ret;
229
230         haps = acpi_driver_data(to_acpi_device(device));
231
232         /* Set the stored protection level */
233         ret = toshiba_haps_protection_level(haps->acpi_dev->handle,
234                                             haps->protection_level);
235
236         /* Reset the protection on resume */
237         ret = toshiba_haps_reset_protection(haps->acpi_dev->handle);
238         if (ret != 0)
239                 return ret;
240
241         return ret;
242 }
243 #endif
244
245 static SIMPLE_DEV_PM_OPS(toshiba_haps_pm,
246                          toshiba_haps_suspend, toshiba_haps_resume);
247
248 static const struct acpi_device_id haps_device_ids[] = {
249         {"TOS620A", 0},
250         {"", 0},
251 };
252 MODULE_DEVICE_TABLE(acpi, haps_device_ids);
253
254 static struct acpi_driver toshiba_haps_driver = {
255         .name = "Toshiba HAPS",
256         .owner = THIS_MODULE,
257         .ids = haps_device_ids,
258         .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
259         .ops = {
260                 .add =          toshiba_haps_add,
261                 .remove =       toshiba_haps_remove,
262                 .notify =       toshiba_haps_notify,
263         },
264         .drv.pm = &toshiba_haps_pm,
265 };
266
267 module_acpi_driver(toshiba_haps_driver);