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 += sysfs_emit_at(buf, count,
31			       "ro|rw|cancel|cold|disable-jump|hibernate|cold-ap-off");
32	count += sysfs_emit_at(buf, count, " [at-shutdown]\n");
33	return count;
34}
35
36static ssize_t reboot_store(struct device *dev,
37			    struct device_attribute *attr,
38			    const char *buf, size_t count)
39{
40	static const struct {
41		const char * const str;
42		uint8_t cmd;
43		uint8_t flags;
44	} words[] = {
45		{"cancel",       EC_REBOOT_CANCEL, 0},
46		{"ro",           EC_REBOOT_JUMP_RO, 0},
47		{"rw",           EC_REBOOT_JUMP_RW, 0},
48		{"cold-ap-off",  EC_REBOOT_COLD_AP_OFF, 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 += sysfs_emit_at(buf, count, "RO version:    %s\n", r_ver->version_string_ro);
141	count += sysfs_emit_at(buf, count, "RW version:    %s\n", r_ver->version_string_rw);
142	count += sysfs_emit_at(buf, count, "Firmware copy: %s\n",
143			   (r_ver->current_image < ARRAY_SIZE(image_names) ?
144			    image_names[r_ver->current_image] : "?"));
145
146	/* Get build info. */
147	msg->command = EC_CMD_GET_BUILD_INFO + ec->cmd_offset;
148	msg->insize = EC_HOST_PARAM_SIZE;
149	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
150	if (ret < 0) {
151		count += sysfs_emit_at(buf, count,
152				   "Build info:    XFER / EC ERROR %d / %d\n",
153				   ret, msg->result);
154	} else {
155		msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
156		count += sysfs_emit_at(buf, count, "Build info:    %s\n", msg->data);
157	}
158
159	/* Get chip info. */
160	msg->command = EC_CMD_GET_CHIP_INFO + ec->cmd_offset;
161	msg->insize = sizeof(*r_chip);
162	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
163	if (ret < 0) {
164		count += sysfs_emit_at(buf, count,
165				   "Chip info:     XFER / EC ERROR %d / %d\n",
166				   ret, msg->result);
167	} else {
168		r_chip = (struct ec_response_get_chip_info *)msg->data;
169
170		r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
171		r_chip->name[sizeof(r_chip->name) - 1] = '\0';
172		r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
173		count += sysfs_emit_at(buf, count, "Chip vendor:   %s\n", r_chip->vendor);
174		count += sysfs_emit_at(buf, count, "Chip name:     %s\n", r_chip->name);
175		count += sysfs_emit_at(buf, count, "Chip revision: %s\n", r_chip->revision);
176	}
177
178	/* Get board version */
179	msg->command = EC_CMD_GET_BOARD_VERSION + ec->cmd_offset;
180	msg->insize = sizeof(*r_board);
181	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
182	if (ret < 0) {
183		count += sysfs_emit_at(buf, count,
184				   "Board version: XFER / EC ERROR %d / %d\n",
185				   ret, msg->result);
186	} else {
187		r_board = (struct ec_response_board_version *)msg->data;
188
189		count += sysfs_emit_at(buf, count,
190				   "Board version: %d\n",
191				   r_board->board_version);
192	}
193
194exit:
195	kfree(msg);
196	return count;
197}
198
199static ssize_t flashinfo_show(struct device *dev,
200			      struct device_attribute *attr, char *buf)
201{
202	struct ec_response_flash_info *resp;
203	struct cros_ec_command *msg;
204	int ret;
205	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
206
207	msg = kmalloc(sizeof(*msg) + sizeof(*resp), GFP_KERNEL);
208	if (!msg)
209		return -ENOMEM;
210
211	/* The flash info shouldn't ever change, but ask each time anyway. */
212	msg->version = 0;
213	msg->command = EC_CMD_FLASH_INFO + ec->cmd_offset;
214	msg->insize = sizeof(*resp);
215	msg->outsize = 0;
216	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
217	if (ret < 0)
218		goto exit;
219
220	resp = (struct ec_response_flash_info *)msg->data;
221
222	ret = sysfs_emit(buf,
223			"FlashSize %d\nWriteSize %d\n"
224			"EraseSize %d\nProtectSize %d\n",
225			resp->flash_size, resp->write_block_size,
226			resp->erase_block_size, resp->protect_block_size);
227exit:
228	kfree(msg);
229	return ret;
230}
231
232/* Keyboard wake angle control */
233static ssize_t kb_wake_angle_show(struct device *dev,
234				  struct device_attribute *attr, char *buf)
235{
236	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
237	struct ec_response_motion_sense *resp;
238	struct ec_params_motion_sense *param;
239	struct cros_ec_command *msg;
240	int ret;
241
242	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
243	if (!msg)
244		return -ENOMEM;
245
246	param = (struct ec_params_motion_sense *)msg->data;
247	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
248	msg->version = 2;
249	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
250	param->kb_wake_angle.data = EC_MOTION_SENSE_NO_VALUE;
251	msg->outsize = sizeof(*param);
252	msg->insize = sizeof(*resp);
253
254	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
255	if (ret < 0)
256		goto exit;
257
258	resp = (struct ec_response_motion_sense *)msg->data;
259	ret = sysfs_emit(buf, "%d\n", resp->kb_wake_angle.ret);
260exit:
261	kfree(msg);
262	return ret;
263}
264
265static ssize_t kb_wake_angle_store(struct device *dev,
266				   struct device_attribute *attr,
267				   const char *buf, size_t count)
268{
269	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
270	struct ec_params_motion_sense *param;
271	struct cros_ec_command *msg;
272	u16 angle;
273	int ret;
274
275	ret = kstrtou16(buf, 0, &angle);
276	if (ret)
277		return ret;
278
279	msg = kmalloc(sizeof(*msg) + EC_HOST_PARAM_SIZE, GFP_KERNEL);
280	if (!msg)
281		return -ENOMEM;
282
283	param = (struct ec_params_motion_sense *)msg->data;
284	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
285	msg->version = 2;
286	param->cmd = MOTIONSENSE_CMD_KB_WAKE_ANGLE;
287	param->kb_wake_angle.data = angle;
288	msg->outsize = sizeof(*param);
289	msg->insize = sizeof(struct ec_response_motion_sense);
290
291	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
292	kfree(msg);
293	if (ret < 0)
294		return ret;
295	return count;
296}
297
298/* Module initialization */
299
300static DEVICE_ATTR_RW(reboot);
301static DEVICE_ATTR_RO(version);
302static DEVICE_ATTR_RO(flashinfo);
303static DEVICE_ATTR_RW(kb_wake_angle);
304
305static struct attribute *__ec_attrs[] = {
306	&dev_attr_kb_wake_angle.attr,
307	&dev_attr_reboot.attr,
308	&dev_attr_version.attr,
309	&dev_attr_flashinfo.attr,
310	NULL,
311};
312
313static umode_t cros_ec_ctrl_visible(struct kobject *kobj,
314				    struct attribute *a, int n)
315{
316	struct device *dev = kobj_to_dev(kobj);
317	struct cros_ec_dev *ec = to_cros_ec_dev(dev);
318
319	if (a == &dev_attr_kb_wake_angle.attr && !ec->has_kb_wake_angle)
320		return 0;
321
322	return a->mode;
323}
324
325static const struct attribute_group cros_ec_attr_group = {
326	.attrs = __ec_attrs,
327	.is_visible = cros_ec_ctrl_visible,
328};
329
330static int cros_ec_sysfs_probe(struct platform_device *pd)
331{
332	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
333	struct device *dev = &pd->dev;
334	int ret;
335
336	ret = sysfs_create_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
337	if (ret < 0)
338		dev_err(dev, "failed to create attributes. err=%d\n", ret);
339
340	return ret;
341}
342
343static void cros_ec_sysfs_remove(struct platform_device *pd)
344{
345	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
346
347	sysfs_remove_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
348}
349
350static struct platform_driver cros_ec_sysfs_driver = {
351	.driver = {
352		.name = DRV_NAME,
353	},
354	.probe = cros_ec_sysfs_probe,
355	.remove_new = cros_ec_sysfs_remove,
356};
357
358module_platform_driver(cros_ec_sysfs_driver);
359
360MODULE_LICENSE("GPL");
361MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs");
362MODULE_ALIAS("platform:" DRV_NAME);
363