1 // SPDX-License-Identifier: GPL-2.0+
2 // Expose the ChromeOS EC through sysfs
3 //
4 // Copyright (C) 2014 Google, Inc.
5 
6 #include <linux/ctype.h>
7 #include <linux/delay.h>
8 #include <linux/device.h>
9 #include <linux/fs.h>
10 #include <linux/kobject.h>
11 #include <linux/module.h>
12 #include <linux/platform_data/cros_ec_commands.h>
13 #include <linux/platform_data/cros_ec_proto.h>
14 #include <linux/platform_device.h>
15 #include <linux/printk.h>
16 #include <linux/slab.h>
17 #include <linux/stat.h>
18 #include <linux/types.h>
19 #include <linux/uaccess.h>
20 
21 #define DRV_NAME "cros-ec-sysfs"
22 
23 /* Accessor functions */
24 
25 static ssize_t reboot_show(struct device *dev,
26 			   struct device_attribute *attr, char *buf)
27 {
28 	int count = 0;
29 
30 	count += scnprintf(buf + count, PAGE_SIZE - count,
31 			   "ro|rw|cancel|cold|disable-jump|hibernate");
32 	count += scnprintf(buf + count, PAGE_SIZE - count,
33 			   " [at-shutdown]\n");
34 	return count;
35 }
36 
37 static ssize_t reboot_store(struct device *dev,
38 			    struct device_attribute *attr,
39 			    const char *buf, size_t count)
40 {
41 	static const struct {
42 		const char * const str;
43 		uint8_t cmd;
44 		uint8_t flags;
45 	} words[] = {
46 		{"cancel",       EC_REBOOT_CANCEL, 0},
47 		{"ro",           EC_REBOOT_JUMP_RO, 0},
48 		{"rw",           EC_REBOOT_JUMP_RW, 0},
49 		{"cold",         EC_REBOOT_COLD, 0},
50 		{"disable-jump", EC_REBOOT_DISABLE_JUMP, 0},
51 		{"hibernate",    EC_REBOOT_HIBERNATE, 0},
52 		{"at-shutdown",  -1, EC_REBOOT_FLAG_ON_AP_SHUTDOWN},
53 	};
54 	struct cros_ec_command *msg;
55 	struct ec_params_reboot_ec *param;
56 	int got_cmd = 0, offset = 0;
57 	int i;
58 	int ret;
59 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
60 
61 	msg = kmalloc(sizeof(*msg) + sizeof(*param), GFP_KERNEL);
62 	if (!msg)
63 		return -ENOMEM;
64 
65 	param = (struct ec_params_reboot_ec *)msg->data;
66 
67 	param->flags = 0;
68 	while (1) {
69 		/* Find word to start scanning */
70 		while (buf[offset] && isspace(buf[offset]))
71 			offset++;
72 		if (!buf[offset])
73 			break;
74 
75 		for (i = 0; i < ARRAY_SIZE(words); i++) {
76 			if (!strncasecmp(words[i].str, buf+offset,
77 					 strlen(words[i].str))) {
78 				if (words[i].flags) {
79 					param->flags |= words[i].flags;
80 				} else {
81 					param->cmd = words[i].cmd;
82 					got_cmd = 1;
83 				}
84 				break;
85 			}
86 		}
87 
88 		/* On to the next word, if any */
89 		while (buf[offset] && !isspace(buf[offset]))
90 			offset++;
91 	}
92 
93 	if (!got_cmd) {
94 		count = -EINVAL;
95 		goto exit;
96 	}
97 
98 	msg->version = 0;
99 	msg->command = EC_CMD_REBOOT_EC + ec->cmd_offset;
100 	msg->outsize = sizeof(*param);
101 	msg->insize = 0;
102 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
103 	if (ret < 0)
104 		count = ret;
105 exit:
106 	kfree(msg);
107 	return count;
108 }
109 
110 static ssize_t version_show(struct device *dev,
111 			    struct device_attribute *attr, char *buf)
112 {
113 	static const char * const image_names[] = {"unknown", "RO", "RW"};
114 	struct ec_response_get_version *r_ver;
115 	struct ec_response_get_chip_info *r_chip;
116 	struct ec_response_board_version *r_board;
117 	struct cros_ec_command *msg;
118 	int ret;
119 	int count = 0;
120 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
121 
122 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
123 	if (!msg)
124 		return -ENOMEM;
125 
126 	/* Get versions. RW may change. */
127 	msg->version = 0;
128 	msg->command = EC_CMD_GET_VERSION + ec->cmd_offset;
129 	msg->insize = sizeof(*r_ver);
130 	msg->outsize = 0;
131 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
132 	if (ret < 0) {
133 		count = ret;
134 		goto exit;
135 	}
136 	r_ver = (struct ec_response_get_version *)msg->data;
137 	/* Strings should be null-terminated, but let's be sure. */
138 	r_ver->version_string_ro[sizeof(r_ver->version_string_ro) - 1] = '\0';
139 	r_ver->version_string_rw[sizeof(r_ver->version_string_rw) - 1] = '\0';
140 	count += scnprintf(buf + count, PAGE_SIZE - count,
141 			   "RO version:    %s\n", r_ver->version_string_ro);
142 	count += scnprintf(buf + count, PAGE_SIZE - count,
143 			   "RW version:    %s\n", r_ver->version_string_rw);
144 	count += scnprintf(buf + count, PAGE_SIZE - count,
145 			   "Firmware copy: %s\n",
146 			   (r_ver->current_image < ARRAY_SIZE(image_names) ?
147 			    image_names[r_ver->current_image] : "?"));
148 
149 	/* Get build info. */
150 	msg->command = EC_CMD_GET_BUILD_INFO + ec->cmd_offset;
151 	msg->insize = EC_HOST_PARAM_SIZE;
152 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
153 	if (ret < 0) {
154 		count += scnprintf(buf + count, PAGE_SIZE - count,
155 				   "Build info:    XFER / EC ERROR %d / %d\n",
156 				   ret, msg->result);
157 	} else {
158 		msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
159 		count += scnprintf(buf + count, PAGE_SIZE - count,
160 				   "Build info:    %s\n", msg->data);
161 	}
162 
163 	/* Get chip info. */
164 	msg->command = EC_CMD_GET_CHIP_INFO + ec->cmd_offset;
165 	msg->insize = sizeof(*r_chip);
166 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
167 	if (ret < 0) {
168 		count += scnprintf(buf + count, PAGE_SIZE - count,
169 				   "Chip info:     XFER / EC ERROR %d / %d\n",
170 				   ret, msg->result);
171 	} else {
172 		r_chip = (struct ec_response_get_chip_info *)msg->data;
173 
174 		r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
175 		r_chip->name[sizeof(r_chip->name) - 1] = '\0';
176 		r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
177 		count += scnprintf(buf + count, PAGE_SIZE - count,
178 				   "Chip vendor:   %s\n", r_chip->vendor);
179 		count += scnprintf(buf + count, PAGE_SIZE - count,
180 				   "Chip name:     %s\n", r_chip->name);
181 		count += scnprintf(buf + count, PAGE_SIZE - count,
182 				   "Chip revision: %s\n", r_chip->revision);
183 	}
184 
185 	/* Get board version */
186 	msg->command = EC_CMD_GET_BOARD_VERSION + ec->cmd_offset;
187 	msg->insize = sizeof(*r_board);
188 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
189 	if (ret < 0) {
190 		count += scnprintf(buf + count, PAGE_SIZE - count,
191 				   "Board version: XFER / EC ERROR %d / %d\n",
192 				   ret, msg->result);
193 	} else {
194 		r_board = (struct ec_response_board_version *)msg->data;
195 
196 		count += scnprintf(buf + count, PAGE_SIZE - count,
197 				   "Board version: %d\n",
198 				   r_board->board_version);
199 	}
200 
201 exit:
202 	kfree(msg);
203 	return count;
204 }
205 
206 static ssize_t flashinfo_show(struct device *dev,
207 			      struct device_attribute *attr, char *buf)
208 {
209 	struct ec_response_flash_info *resp;
210 	struct cros_ec_command *msg;
211 	int ret;
212 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
213 
214 	msg = kmalloc(sizeof(*msg) + sizeof(*resp), GFP_KERNEL);
215 	if (!msg)
216 		return -ENOMEM;
217 
218 	/* The flash info shouldn't ever change, but ask each time anyway. */
219 	msg->version = 0;
220 	msg->command = EC_CMD_FLASH_INFO + ec->cmd_offset;
221 	msg->insize = sizeof(*resp);
222 	msg->outsize = 0;
223 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
224 	if (ret < 0)
225 		goto exit;
226 
227 	resp = (struct ec_response_flash_info *)msg->data;
228 
229 	ret = scnprintf(buf, PAGE_SIZE,
230 			"FlashSize %d\nWriteSize %d\n"
231 			"EraseSize %d\nProtectSize %d\n",
232 			resp->flash_size, resp->write_block_size,
233 			resp->erase_block_size, resp->protect_block_size);
234 exit:
235 	kfree(msg);
236 	return ret;
237 }
238 
239 /* Keyboard wake angle control */
240 static ssize_t kb_wake_angle_show(struct device *dev,
241 				  struct device_attribute *attr, char *buf)
242 {
243 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
244 	struct ec_response_motion_sense *resp;
245 	struct ec_params_motion_sense *param;
246 	struct cros_ec_command *msg;
247 	int ret;
248 
249 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
250 	if (!msg)
251 		return -ENOMEM;
252 
253 	param = (struct ec_params_motion_sense *)msg->data;
254 	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
255 	msg->version = 2;
256 	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
257 	param->kb_wake_angle.data = EC_MOTION_SENSE_NO_VALUE;
258 	msg->outsize = sizeof(*param);
259 	msg->insize = sizeof(*resp);
260 
261 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
262 	if (ret < 0)
263 		goto exit;
264 
265 	resp = (struct ec_response_motion_sense *)msg->data;
266 	ret = scnprintf(buf, PAGE_SIZE, "%d\n", resp->kb_wake_angle.ret);
267 exit:
268 	kfree(msg);
269 	return ret;
270 }
271 
272 static ssize_t kb_wake_angle_store(struct device *dev,
273 				   struct device_attribute *attr,
274 				   const char *buf, size_t count)
275 {
276 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
277 	struct ec_params_motion_sense *param;
278 	struct cros_ec_command *msg;
279 	u16 angle;
280 	int ret;
281 
282 	ret = kstrtou16(buf, 0, &angle);
283 	if (ret)
284 		return ret;
285 
286 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
287 	if (!msg)
288 		return -ENOMEM;
289 
290 	param = (struct ec_params_motion_sense *)msg->data;
291 	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
292 	msg->version = 2;
293 	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
294 	param->kb_wake_angle.data = angle;
295 	msg->outsize = sizeof(*param);
296 	msg->insize = sizeof(struct ec_response_motion_sense);
297 
298 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
299 	kfree(msg);
300 	if (ret < 0)
301 		return ret;
302 	return count;
303 }
304 
305 /* Module initialization */
306 
307 static DEVICE_ATTR_RW(reboot);
308 static DEVICE_ATTR_RO(version);
309 static DEVICE_ATTR_RO(flashinfo);
310 static DEVICE_ATTR_RW(kb_wake_angle);
311 
312 static struct attribute *__ec_attrs[] = {
313 	&dev_attr_kb_wake_angle.attr,
314 	&dev_attr_reboot.attr,
315 	&dev_attr_version.attr,
316 	&dev_attr_flashinfo.attr,
317 	NULL,
318 };
319 
320 static umode_t cros_ec_ctrl_visible(struct kobject *kobj,
321 				    struct attribute *a, int n)
322 {
323 	struct device *dev = kobj_to_dev(kobj);
324 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
325 
326 	if (a == &dev_attr_kb_wake_angle.attr && !ec->has_kb_wake_angle)
327 		return 0;
328 
329 	return a->mode;
330 }
331 
332 static struct attribute_group cros_ec_attr_group = {
333 	.attrs = __ec_attrs,
334 	.is_visible = cros_ec_ctrl_visible,
335 };
336 
337 static int cros_ec_sysfs_probe(struct platform_device *pd)
338 {
339 	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
340 	struct device *dev = &pd->dev;
341 	int ret;
342 
343 	ret = sysfs_create_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
344 	if (ret < 0)
345 		dev_err(dev, "failed to create attributes. err=%d\n", ret);
346 
347 	return ret;
348 }
349 
350 static int cros_ec_sysfs_remove(struct platform_device *pd)
351 {
352 	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
353 
354 	sysfs_remove_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
355 
356 	return 0;
357 }
358 
359 static struct platform_driver cros_ec_sysfs_driver = {
360 	.driver = {
361 		.name = DRV_NAME,
362 	},
363 	.probe = cros_ec_sysfs_probe,
364 	.remove = cros_ec_sysfs_remove,
365 };
366 
367 module_platform_driver(cros_ec_sysfs_driver);
368 
369 MODULE_LICENSE("GPL");
370 MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs");
371 MODULE_ALIAS("platform:" DRV_NAME);
372