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
25static 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
37static 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;
105exit:
106	kfree(msg);
107	return count;
108}
109
110static 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
201exit:
202	kfree(msg);
203	return count;
204}
205
206static 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);
234exit:
235	kfree(msg);
236	return ret;
237}
238
239/* Keyboard wake angle control */
240static 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);
267exit:
268	kfree(msg);
269	return ret;
270}
271
272static 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
307static DEVICE_ATTR_RW(reboot);
308static DEVICE_ATTR_RO(version);
309static DEVICE_ATTR_RO(flashinfo);
310static DEVICE_ATTR_RW(kb_wake_angle);
311
312static 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
320static 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
332static struct attribute_group cros_ec_attr_group = {
333	.attrs = __ec_attrs,
334	.is_visible = cros_ec_ctrl_visible,
335};
336
337static 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
350static 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
359static 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
367module_platform_driver(cros_ec_sysfs_driver);
368
369MODULE_LICENSE("GPL");
370MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs");
371MODULE_ALIAS("platform:" DRV_NAME);
372