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(object: handle, pathname: "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, method: "PTLV" , arg: 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, fmt: "%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(s: buf, base: 0, res: &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(handle: 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(s: buf, base: 0, res: &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(handle: 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\n" , event); |
135 | |
136 | acpi_bus_generate_netlink_event(device->pnp.device_class, |
137 | dev_name(dev: &device->dev), |
138 | event, 0); |
139 | } |
140 | |
141 | static void toshiba_haps_remove(struct acpi_device *device) |
142 | { |
143 | sysfs_remove_group(kobj: &device->dev.kobj, grp: &haps_attr_group); |
144 | |
145 | if (toshiba_haps) |
146 | toshiba_haps = NULL; |
147 | } |
148 | |
149 | /* Helper function */ |
150 | static 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, pathname: "_STA" , NULL, data: &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 | |
173 | static 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(handle: acpi_dev->handle)) |
182 | return -ENODEV; |
183 | |
184 | pr_info("Toshiba HDD Active Protection Sensor device\n" ); |
185 | |
186 | haps = kzalloc(size: 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(dev: &acpi_dev->dev, data: haps); |
194 | |
195 | /* Set the protection level, currently at level 2 (Medium) */ |
196 | ret = toshiba_haps_protection_level(handle: acpi_dev->handle, level: 2); |
197 | if (ret != 0) |
198 | return ret; |
199 | |
200 | ret = sysfs_create_group(kobj: &acpi_dev->dev.kobj, grp: &haps_attr_group); |
201 | if (ret) |
202 | return ret; |
203 | |
204 | toshiba_haps = haps; |
205 | |
206 | return 0; |
207 | } |
208 | |
209 | #ifdef CONFIG_PM_SLEEP |
210 | static 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(handle: haps->acpi_dev->handle, level: 0); |
219 | |
220 | return ret; |
221 | } |
222 | |
223 | static 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(handle: haps->acpi_dev->handle, |
232 | level: haps->protection_level); |
233 | |
234 | /* Reset the protection on resume */ |
235 | ret = toshiba_haps_reset_protection(handle: haps->acpi_dev->handle); |
236 | if (ret != 0) |
237 | return ret; |
238 | |
239 | return ret; |
240 | } |
241 | #endif |
242 | |
243 | static SIMPLE_DEV_PM_OPS(toshiba_haps_pm, |
244 | toshiba_haps_suspend, toshiba_haps_resume); |
245 | |
246 | static const struct acpi_device_id haps_device_ids[] = { |
247 | {"TOS620A" , 0}, |
248 | {"" , 0}, |
249 | }; |
250 | MODULE_DEVICE_TABLE(acpi, haps_device_ids); |
251 | |
252 | static struct acpi_driver toshiba_haps_driver = { |
253 | .name = "Toshiba HAPS" , |
254 | .owner = THIS_MODULE, |
255 | .ids = haps_device_ids, |
256 | .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS, |
257 | .ops = { |
258 | .add = toshiba_haps_add, |
259 | .remove = toshiba_haps_remove, |
260 | .notify = toshiba_haps_notify, |
261 | }, |
262 | .drv.pm = &toshiba_haps_pm, |
263 | }; |
264 | |
265 | module_acpi_driver(toshiba_haps_driver); |
266 | |