xref: /openbmc/linux/drivers/platform/chrome/cros_ec_sysfs.c (revision 9c6d26df1fae6ad4718d51c48e6517913304ed27)
1 /*
2  * cros_ec_sysfs - expose the Chrome OS EC through sysfs
3  *
4  * Copyright (C) 2014 Google, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program. If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #define pr_fmt(fmt) "cros_ec_sysfs: " fmt
21 
22 #include <linux/ctype.h>
23 #include <linux/delay.h>
24 #include <linux/device.h>
25 #include <linux/fs.h>
26 #include <linux/kobject.h>
27 #include <linux/mfd/cros_ec.h>
28 #include <linux/mfd/cros_ec_commands.h>
29 #include <linux/module.h>
30 #include <linux/platform_device.h>
31 #include <linux/printk.h>
32 #include <linux/slab.h>
33 #include <linux/stat.h>
34 #include <linux/types.h>
35 #include <linux/uaccess.h>
36 
37 #define to_cros_ec_dev(dev)  container_of(dev, struct cros_ec_dev, class_dev)
38 
39 /* Accessor functions */
40 
41 static ssize_t reboot_show(struct device *dev,
42 			   struct device_attribute *attr, char *buf)
43 {
44 	int count = 0;
45 
46 	count += scnprintf(buf + count, PAGE_SIZE - count,
47 			   "ro|rw|cancel|cold|disable-jump|hibernate");
48 	count += scnprintf(buf + count, PAGE_SIZE - count,
49 			   " [at-shutdown]\n");
50 	return count;
51 }
52 
53 static ssize_t reboot_store(struct device *dev,
54 			    struct device_attribute *attr,
55 			    const char *buf, size_t count)
56 {
57 	static const struct {
58 		const char * const str;
59 		uint8_t cmd;
60 		uint8_t flags;
61 	} words[] = {
62 		{"cancel",       EC_REBOOT_CANCEL, 0},
63 		{"ro",           EC_REBOOT_JUMP_RO, 0},
64 		{"rw",           EC_REBOOT_JUMP_RW, 0},
65 		{"cold",         EC_REBOOT_COLD, 0},
66 		{"disable-jump", EC_REBOOT_DISABLE_JUMP, 0},
67 		{"hibernate",    EC_REBOOT_HIBERNATE, 0},
68 		{"at-shutdown",  -1, EC_REBOOT_FLAG_ON_AP_SHUTDOWN},
69 	};
70 	struct cros_ec_command *msg;
71 	struct ec_params_reboot_ec *param;
72 	int got_cmd = 0, offset = 0;
73 	int i;
74 	int ret;
75 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
76 
77 	msg = kmalloc(sizeof(*msg) + sizeof(*param), GFP_KERNEL);
78 	if (!msg)
79 		return -ENOMEM;
80 
81 	param = (struct ec_params_reboot_ec *)msg->data;
82 
83 	param->flags = 0;
84 	while (1) {
85 		/* Find word to start scanning */
86 		while (buf[offset] && isspace(buf[offset]))
87 			offset++;
88 		if (!buf[offset])
89 			break;
90 
91 		for (i = 0; i < ARRAY_SIZE(words); i++) {
92 			if (!strncasecmp(words[i].str, buf+offset,
93 					 strlen(words[i].str))) {
94 				if (words[i].flags) {
95 					param->flags |= words[i].flags;
96 				} else {
97 					param->cmd = words[i].cmd;
98 					got_cmd = 1;
99 				}
100 				break;
101 			}
102 		}
103 
104 		/* On to the next word, if any */
105 		while (buf[offset] && !isspace(buf[offset]))
106 			offset++;
107 	}
108 
109 	if (!got_cmd) {
110 		count = -EINVAL;
111 		goto exit;
112 	}
113 
114 	msg->version = 0;
115 	msg->command = EC_CMD_REBOOT_EC + ec->cmd_offset;
116 	msg->outsize = sizeof(*param);
117 	msg->insize = 0;
118 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
119 	if (ret < 0)
120 		count = ret;
121 exit:
122 	kfree(msg);
123 	return count;
124 }
125 
126 static ssize_t version_show(struct device *dev,
127 			    struct device_attribute *attr, char *buf)
128 {
129 	static const char * const image_names[] = {"unknown", "RO", "RW"};
130 	struct ec_response_get_version *r_ver;
131 	struct ec_response_get_chip_info *r_chip;
132 	struct ec_response_board_version *r_board;
133 	struct cros_ec_command *msg;
134 	int ret;
135 	int count = 0;
136 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
137 
138 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
139 	if (!msg)
140 		return -ENOMEM;
141 
142 	/* Get versions. RW may change. */
143 	msg->version = 0;
144 	msg->command = EC_CMD_GET_VERSION + ec->cmd_offset;
145 	msg->insize = sizeof(*r_ver);
146 	msg->outsize = 0;
147 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
148 	if (ret < 0) {
149 		count = ret;
150 		goto exit;
151 	}
152 	r_ver = (struct ec_response_get_version *)msg->data;
153 	/* Strings should be null-terminated, but let's be sure. */
154 	r_ver->version_string_ro[sizeof(r_ver->version_string_ro) - 1] = '\0';
155 	r_ver->version_string_rw[sizeof(r_ver->version_string_rw) - 1] = '\0';
156 	count += scnprintf(buf + count, PAGE_SIZE - count,
157 			   "RO version:    %s\n", r_ver->version_string_ro);
158 	count += scnprintf(buf + count, PAGE_SIZE - count,
159 			   "RW version:    %s\n", r_ver->version_string_rw);
160 	count += scnprintf(buf + count, PAGE_SIZE - count,
161 			   "Firmware copy: %s\n",
162 			   (r_ver->current_image < ARRAY_SIZE(image_names) ?
163 			    image_names[r_ver->current_image] : "?"));
164 
165 	/* Get build info. */
166 	msg->command = EC_CMD_GET_BUILD_INFO + ec->cmd_offset;
167 	msg->insize = EC_HOST_PARAM_SIZE;
168 	ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
169 	if (ret < 0)
170 		count += scnprintf(buf + count, PAGE_SIZE - count,
171 				   "Build info:    XFER ERROR %d\n", ret);
172 	else if (msg->result != EC_RES_SUCCESS)
173 		count += scnprintf(buf + count, PAGE_SIZE - count,
174 				   "Build info:    EC error %d\n", msg->result);
175 	else {
176 		msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
177 		count += scnprintf(buf + count, PAGE_SIZE - count,
178 				   "Build info:    %s\n", msg->data);
179 	}
180 
181 	/* Get chip info. */
182 	msg->command = EC_CMD_GET_CHIP_INFO + ec->cmd_offset;
183 	msg->insize = sizeof(*r_chip);
184 	ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
185 	if (ret < 0)
186 		count += scnprintf(buf + count, PAGE_SIZE - count,
187 				   "Chip info:     XFER ERROR %d\n", ret);
188 	else if (msg->result != EC_RES_SUCCESS)
189 		count += scnprintf(buf + count, PAGE_SIZE - count,
190 				   "Chip info:     EC error %d\n", msg->result);
191 	else {
192 		r_chip = (struct ec_response_get_chip_info *)msg->data;
193 
194 		r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
195 		r_chip->name[sizeof(r_chip->name) - 1] = '\0';
196 		r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
197 		count += scnprintf(buf + count, PAGE_SIZE - count,
198 				   "Chip vendor:   %s\n", r_chip->vendor);
199 		count += scnprintf(buf + count, PAGE_SIZE - count,
200 				   "Chip name:     %s\n", r_chip->name);
201 		count += scnprintf(buf + count, PAGE_SIZE - count,
202 				   "Chip revision: %s\n", r_chip->revision);
203 	}
204 
205 	/* Get board version */
206 	msg->command = EC_CMD_GET_BOARD_VERSION + ec->cmd_offset;
207 	msg->insize = sizeof(*r_board);
208 	ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
209 	if (ret < 0)
210 		count += scnprintf(buf + count, PAGE_SIZE - count,
211 				   "Board version: XFER ERROR %d\n", ret);
212 	else if (msg->result != EC_RES_SUCCESS)
213 		count += scnprintf(buf + count, PAGE_SIZE - count,
214 				   "Board version: EC error %d\n", msg->result);
215 	else {
216 		r_board = (struct ec_response_board_version *)msg->data;
217 
218 		count += scnprintf(buf + count, PAGE_SIZE - count,
219 				   "Board version: %d\n",
220 				   r_board->board_version);
221 	}
222 
223 exit:
224 	kfree(msg);
225 	return count;
226 }
227 
228 static ssize_t flashinfo_show(struct device *dev,
229 			      struct device_attribute *attr, char *buf)
230 {
231 	struct ec_response_flash_info *resp;
232 	struct cros_ec_command *msg;
233 	int ret;
234 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
235 
236 	msg = kmalloc(sizeof(*msg) + sizeof(*resp), GFP_KERNEL);
237 	if (!msg)
238 		return -ENOMEM;
239 
240 	/* The flash info shouldn't ever change, but ask each time anyway. */
241 	msg->version = 0;
242 	msg->command = EC_CMD_FLASH_INFO + ec->cmd_offset;
243 	msg->insize = sizeof(*resp);
244 	msg->outsize = 0;
245 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
246 	if (ret < 0)
247 		goto exit;
248 
249 	resp = (struct ec_response_flash_info *)msg->data;
250 
251 	ret = scnprintf(buf, PAGE_SIZE,
252 			"FlashSize %d\nWriteSize %d\n"
253 			"EraseSize %d\nProtectSize %d\n",
254 			resp->flash_size, resp->write_block_size,
255 			resp->erase_block_size, resp->protect_block_size);
256 exit:
257 	kfree(msg);
258 	return ret;
259 }
260 
261 /* Keyboard wake angle control */
262 static ssize_t kb_wake_angle_show(struct device *dev,
263 				  struct device_attribute *attr, char *buf)
264 {
265 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
266 	struct ec_response_motion_sense *resp;
267 	struct ec_params_motion_sense *param;
268 	struct cros_ec_command *msg;
269 	int ret;
270 
271 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
272 	if (!msg)
273 		return -ENOMEM;
274 
275 	param = (struct ec_params_motion_sense *)msg->data;
276 	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
277 	msg->version = 2;
278 	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
279 	param->kb_wake_angle.data = EC_MOTION_SENSE_NO_VALUE;
280 	msg->outsize = sizeof(*param);
281 	msg->insize = sizeof(*resp);
282 
283 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
284 	if (ret < 0)
285 		goto exit;
286 
287 	resp = (struct ec_response_motion_sense *)msg->data;
288 	ret = scnprintf(buf, PAGE_SIZE, "%d\n", resp->kb_wake_angle.ret);
289 exit:
290 	kfree(msg);
291 	return ret;
292 }
293 
294 static ssize_t kb_wake_angle_store(struct device *dev,
295 				   struct device_attribute *attr,
296 				   const char *buf, size_t count)
297 {
298 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
299 	struct ec_params_motion_sense *param;
300 	struct cros_ec_command *msg;
301 	u16 angle;
302 	int ret;
303 
304 	ret = kstrtou16(buf, 0, &angle);
305 	if (ret)
306 		return ret;
307 
308 	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
309 	if (!msg)
310 		return -ENOMEM;
311 
312 	param = (struct ec_params_motion_sense *)msg->data;
313 	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
314 	msg->version = 2;
315 	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
316 	param->kb_wake_angle.data = angle;
317 	msg->outsize = sizeof(*param);
318 	msg->insize = sizeof(struct ec_response_motion_sense);
319 
320 	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
321 	kfree(msg);
322 	if (ret < 0)
323 		return ret;
324 	return count;
325 }
326 
327 /* Module initialization */
328 
329 static DEVICE_ATTR_RW(reboot);
330 static DEVICE_ATTR_RO(version);
331 static DEVICE_ATTR_RO(flashinfo);
332 static DEVICE_ATTR_RW(kb_wake_angle);
333 
334 static struct attribute *__ec_attrs[] = {
335 	&dev_attr_kb_wake_angle.attr,
336 	&dev_attr_reboot.attr,
337 	&dev_attr_version.attr,
338 	&dev_attr_flashinfo.attr,
339 	NULL,
340 };
341 
342 static umode_t cros_ec_ctrl_visible(struct kobject *kobj,
343 				    struct attribute *a, int n)
344 {
345 	struct device *dev = container_of(kobj, struct device, kobj);
346 	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
347 
348 	if (a == &dev_attr_kb_wake_angle.attr && !ec->has_kb_wake_angle)
349 		return 0;
350 
351 	return a->mode;
352 }
353 
354 struct attribute_group cros_ec_attr_group = {
355 	.attrs = __ec_attrs,
356 	.is_visible = cros_ec_ctrl_visible,
357 };
358 EXPORT_SYMBOL(cros_ec_attr_group);
359 
360 MODULE_LICENSE("GPL");
361 MODULE_DESCRIPTION("ChromeOS EC control driver");
362