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|cold-ap-off");
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-ap-off",  EC_REBOOT_COLD_AP_OFF, 0},
50 		{"cold",         EC_REBOOT_COLD, 0},
51 		{"disable-jump", EC_REBOOT_DISABLE_JUMP, 0},
52 		{"hibernate",    EC_REBOOT_HIBERNATE, 0},
53 		{"at-shutdown",  -1, EC_REBOOT_FLAG_ON_AP_SHUTDOWN},
54 	};
55 	struct cros_ec_command *msg;
56 	struct ec_params_reboot_ec *param;
57 	int got_cmd = 0, offset = 0;
58 	int i;
59 	int ret;
60 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
61 
62 	msg = kmalloc(sizeof(*msg) + sizeof(*param), GFP_KERNEL);
63 	if (!msg)
64 		return -ENOMEM;
65 
66 	param = (struct ec_params_reboot_ec *)msg->data;
67 
68 	param->flags = 0;
69 	while (1) {
70 		/* Find word to start scanning */
71 		while (buf[offset] && isspace(buf[offset]))
72 			offset++;
73 		if (!buf[offset])
74 			break;
75 
76 		for (i = 0; i < ARRAY_SIZE(words); i++) {
77 			if (!strncasecmp(words[i].str, buf+offset,
78 					 strlen(words[i].str))) {
79 				if (words[i].flags) {
80 					param->flags |= words[i].flags;
81 				} else {
82 					param->cmd = words[i].cmd;
83 					got_cmd = 1;
84 				}
85 				break;
86 			}
87 		}
88 
89 		/* On to the next word, if any */
90 		while (buf[offset] && !isspace(buf[offset]))
91 			offset++;
92 	}
93 
94 	if (!got_cmd) {
95 		count = -EINVAL;
96 		goto exit;
97 	}
98 
99 	msg->version = 0;
100 	msg->command = EC_CMD_REBOOT_EC + ec->cmd_offset;
101 	msg->outsize = sizeof(*param);
102 	msg->insize = 0;
103 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
104 	if (ret < 0)
105 		count = ret;
106 exit:
107 	kfree(msg);
108 	return count;
109 }
110 
111 static ssize_t version_show(struct device *dev,
112 			    struct device_attribute *attr, char *buf)
113 {
114 	static const char * const image_names[] = {"unknown", "RO", "RW"};
115 	struct ec_response_get_version *r_ver;
116 	struct ec_response_get_chip_info *r_chip;
117 	struct ec_response_board_version *r_board;
118 	struct cros_ec_command *msg;
119 	int ret;
120 	int count = 0;
121 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
122 
123 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
124 	if (!msg)
125 		return -ENOMEM;
126 
127 	/* Get versions. RW may change. */
128 	msg->version = 0;
129 	msg->command = EC_CMD_GET_VERSION + ec->cmd_offset;
130 	msg->insize = sizeof(*r_ver);
131 	msg->outsize = 0;
132 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
133 	if (ret < 0) {
134 		count = ret;
135 		goto exit;
136 	}
137 	r_ver = (struct ec_response_get_version *)msg->data;
138 	/* Strings should be null-terminated, but let's be sure. */
139 	r_ver->version_string_ro[sizeof(r_ver->version_string_ro) - 1] = '\0';
140 	r_ver->version_string_rw[sizeof(r_ver->version_string_rw) - 1] = '\0';
141 	count += scnprintf(buf + count, PAGE_SIZE - count,
142 			   "RO version:    %s\n", r_ver->version_string_ro);
143 	count += scnprintf(buf + count, PAGE_SIZE - count,
144 			   "RW version:    %s\n", r_ver->version_string_rw);
145 	count += scnprintf(buf + count, PAGE_SIZE - count,
146 			   "Firmware copy: %s\n",
147 			   (r_ver->current_image < ARRAY_SIZE(image_names) ?
148 			    image_names[r_ver->current_image] : "?"));
149 
150 	/* Get build info. */
151 	msg->command = EC_CMD_GET_BUILD_INFO + ec->cmd_offset;
152 	msg->insize = EC_HOST_PARAM_SIZE;
153 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
154 	if (ret < 0) {
155 		count += scnprintf(buf + count, PAGE_SIZE - count,
156 				   "Build info:    XFER / EC ERROR %d / %d\n",
157 				   ret, msg->result);
158 	} else {
159 		msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
160 		count += scnprintf(buf + count, PAGE_SIZE - count,
161 				   "Build info:    %s\n", msg->data);
162 	}
163 
164 	/* Get chip info. */
165 	msg->command = EC_CMD_GET_CHIP_INFO + ec->cmd_offset;
166 	msg->insize = sizeof(*r_chip);
167 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
168 	if (ret < 0) {
169 		count += scnprintf(buf + count, PAGE_SIZE - count,
170 				   "Chip info:     XFER / EC ERROR %d / %d\n",
171 				   ret, msg->result);
172 	} else {
173 		r_chip = (struct ec_response_get_chip_info *)msg->data;
174 
175 		r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
176 		r_chip->name[sizeof(r_chip->name) - 1] = '\0';
177 		r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
178 		count += scnprintf(buf + count, PAGE_SIZE - count,
179 				   "Chip vendor:   %s\n", r_chip->vendor);
180 		count += scnprintf(buf + count, PAGE_SIZE - count,
181 				   "Chip name:     %s\n", r_chip->name);
182 		count += scnprintf(buf + count, PAGE_SIZE - count,
183 				   "Chip revision: %s\n", r_chip->revision);
184 	}
185 
186 	/* Get board version */
187 	msg->command = EC_CMD_GET_BOARD_VERSION + ec->cmd_offset;
188 	msg->insize = sizeof(*r_board);
189 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
190 	if (ret < 0) {
191 		count += scnprintf(buf + count, PAGE_SIZE - count,
192 				   "Board version: XFER / EC ERROR %d / %d\n",
193 				   ret, msg->result);
194 	} else {
195 		r_board = (struct ec_response_board_version *)msg->data;
196 
197 		count += scnprintf(buf + count, PAGE_SIZE - count,
198 				   "Board version: %d\n",
199 				   r_board->board_version);
200 	}
201 
202 exit:
203 	kfree(msg);
204 	return count;
205 }
206 
207 static ssize_t flashinfo_show(struct device *dev,
208 			      struct device_attribute *attr, char *buf)
209 {
210 	struct ec_response_flash_info *resp;
211 	struct cros_ec_command *msg;
212 	int ret;
213 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
214 
215 	msg = kmalloc(sizeof(*msg) + sizeof(*resp), GFP_KERNEL);
216 	if (!msg)
217 		return -ENOMEM;
218 
219 	/* The flash info shouldn't ever change, but ask each time anyway. */
220 	msg->version = 0;
221 	msg->command = EC_CMD_FLASH_INFO + ec->cmd_offset;
222 	msg->insize = sizeof(*resp);
223 	msg->outsize = 0;
224 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
225 	if (ret < 0)
226 		goto exit;
227 
228 	resp = (struct ec_response_flash_info *)msg->data;
229 
230 	ret = scnprintf(buf, PAGE_SIZE,
231 			"FlashSize %d\nWriteSize %d\n"
232 			"EraseSize %d\nProtectSize %d\n",
233 			resp->flash_size, resp->write_block_size,
234 			resp->erase_block_size, resp->protect_block_size);
235 exit:
236 	kfree(msg);
237 	return ret;
238 }
239 
240 /* Keyboard wake angle control */
241 static ssize_t kb_wake_angle_show(struct device *dev,
242 				  struct device_attribute *attr, char *buf)
243 {
244 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
245 	struct ec_response_motion_sense *resp;
246 	struct ec_params_motion_sense *param;
247 	struct cros_ec_command *msg;
248 	int ret;
249 
250 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
251 	if (!msg)
252 		return -ENOMEM;
253 
254 	param = (struct ec_params_motion_sense *)msg->data;
255 	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
256 	msg->version = 2;
257 	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
258 	param->kb_wake_angle.data = EC_MOTION_SENSE_NO_VALUE;
259 	msg->outsize = sizeof(*param);
260 	msg->insize = sizeof(*resp);
261 
262 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
263 	if (ret < 0)
264 		goto exit;
265 
266 	resp = (struct ec_response_motion_sense *)msg->data;
267 	ret = scnprintf(buf, PAGE_SIZE, "%d\n", resp->kb_wake_angle.ret);
268 exit:
269 	kfree(msg);
270 	return ret;
271 }
272 
273 static ssize_t kb_wake_angle_store(struct device *dev,
274 				   struct device_attribute *attr,
275 				   const char *buf, size_t count)
276 {
277 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
278 	struct ec_params_motion_sense *param;
279 	struct cros_ec_command *msg;
280 	u16 angle;
281 	int ret;
282 
283 	ret = kstrtou16(buf, 0, &angle);
284 	if (ret)
285 		return ret;
286 
287 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
288 	if (!msg)
289 		return -ENOMEM;
290 
291 	param = (struct ec_params_motion_sense *)msg->data;
292 	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
293 	msg->version = 2;
294 	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
295 	param->kb_wake_angle.data = angle;
296 	msg->outsize = sizeof(*param);
297 	msg->insize = sizeof(struct ec_response_motion_sense);
298 
299 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
300 	kfree(msg);
301 	if (ret < 0)
302 		return ret;
303 	return count;
304 }
305 
306 /* Module initialization */
307 
308 static DEVICE_ATTR_RW(reboot);
309 static DEVICE_ATTR_RO(version);
310 static DEVICE_ATTR_RO(flashinfo);
311 static DEVICE_ATTR_RW(kb_wake_angle);
312 
313 static struct attribute *__ec_attrs[] = {
314 	&dev_attr_kb_wake_angle.attr,
315 	&dev_attr_reboot.attr,
316 	&dev_attr_version.attr,
317 	&dev_attr_flashinfo.attr,
318 	NULL,
319 };
320 
321 static umode_t cros_ec_ctrl_visible(struct kobject *kobj,
322 				    struct attribute *a, int n)
323 {
324 	struct device *dev = kobj_to_dev(kobj);
325 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
326 
327 	if (a == &dev_attr_kb_wake_angle.attr && !ec->has_kb_wake_angle)
328 		return 0;
329 
330 	return a->mode;
331 }
332 
333 static const struct attribute_group cros_ec_attr_group = {
334 	.attrs = __ec_attrs,
335 	.is_visible = cros_ec_ctrl_visible,
336 };
337 
338 static int cros_ec_sysfs_probe(struct platform_device *pd)
339 {
340 	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
341 	struct device *dev = &pd->dev;
342 	int ret;
343 
344 	ret = sysfs_create_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
345 	if (ret < 0)
346 		dev_err(dev, "failed to create attributes. err=%d\n", ret);
347 
348 	return ret;
349 }
350 
351 static int cros_ec_sysfs_remove(struct platform_device *pd)
352 {
353 	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
354 
355 	sysfs_remove_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
356 
357 	return 0;
358 }
359 
360 static struct platform_driver cros_ec_sysfs_driver = {
361 	.driver = {
362 		.name = DRV_NAME,
363 	},
364 	.probe = cros_ec_sysfs_probe,
365 	.remove = cros_ec_sysfs_remove,
366 };
367 
368 module_platform_driver(cros_ec_sysfs_driver);
369 
370 MODULE_LICENSE("GPL");
371 MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs");
372 MODULE_ALIAS("platform:" DRV_NAME);
373