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/stat.h>
33#include <linux/types.h>
34#include <linux/uaccess.h>
35
36#include "cros_ec_dev.h"
37
38/* Accessor functions */
39
40static ssize_t show_ec_reboot(struct device *dev,
41			      struct device_attribute *attr, char *buf)
42{
43	int count = 0;
44
45	count += scnprintf(buf + count, PAGE_SIZE - count,
46			   "ro|rw|cancel|cold|disable-jump|hibernate");
47	count += scnprintf(buf + count, PAGE_SIZE - count,
48			   " [at-shutdown]\n");
49	return count;
50}
51
52static ssize_t store_ec_reboot(struct device *dev,
53			       struct device_attribute *attr,
54			       const char *buf, size_t count)
55{
56	static const struct {
57		const char * const str;
58		uint8_t cmd;
59		uint8_t flags;
60	} words[] = {
61		{"cancel",       EC_REBOOT_CANCEL, 0},
62		{"ro",           EC_REBOOT_JUMP_RO, 0},
63		{"rw",           EC_REBOOT_JUMP_RW, 0},
64		{"cold",         EC_REBOOT_COLD, 0},
65		{"disable-jump", EC_REBOOT_DISABLE_JUMP, 0},
66		{"hibernate",    EC_REBOOT_HIBERNATE, 0},
67		{"at-shutdown",  -1, EC_REBOOT_FLAG_ON_AP_SHUTDOWN},
68	};
69	struct cros_ec_command msg = { 0 };
70	struct ec_params_reboot_ec *param =
71		(struct ec_params_reboot_ec *)msg.outdata;
72	int got_cmd = 0, offset = 0;
73	int i;
74	int ret;
75	struct cros_ec_device *ec = dev_get_drvdata(dev);
76
77	param->flags = 0;
78	while (1) {
79		/* Find word to start scanning */
80		while (buf[offset] && isspace(buf[offset]))
81			offset++;
82		if (!buf[offset])
83			break;
84
85		for (i = 0; i < ARRAY_SIZE(words); i++) {
86			if (!strncasecmp(words[i].str, buf+offset,
87					 strlen(words[i].str))) {
88				if (words[i].flags) {
89					param->flags |= words[i].flags;
90				} else {
91					param->cmd = words[i].cmd;
92					got_cmd = 1;
93				}
94				break;
95			}
96		}
97
98		/* On to the next word, if any */
99		while (buf[offset] && !isspace(buf[offset]))
100			offset++;
101	}
102
103	if (!got_cmd)
104		return -EINVAL;
105
106	msg.command = EC_CMD_REBOOT_EC;
107	msg.outsize = sizeof(param);
108	ret = cros_ec_cmd_xfer(ec, &msg);
109	if (ret < 0)
110		return ret;
111	if (msg.result != EC_RES_SUCCESS) {
112		dev_dbg(ec->dev, "EC result %d\n", msg.result);
113		return -EINVAL;
114	}
115
116	return count;
117}
118
119static ssize_t show_ec_version(struct device *dev,
120			       struct device_attribute *attr, char *buf)
121{
122	static const char * const image_names[] = {"unknown", "RO", "RW"};
123	struct ec_response_get_version *r_ver;
124	struct ec_response_get_chip_info *r_chip;
125	struct ec_response_board_version *r_board;
126	struct cros_ec_command msg = { 0 };
127	int ret;
128	int count = 0;
129	struct cros_ec_device *ec = dev_get_drvdata(dev);
130
131	/* Get versions. RW may change. */
132	msg.command = EC_CMD_GET_VERSION;
133	msg.insize = sizeof(*r_ver);
134	ret = cros_ec_cmd_xfer(ec, &msg);
135	if (ret < 0)
136		return ret;
137	if (msg.result != EC_RES_SUCCESS)
138		return scnprintf(buf, PAGE_SIZE,
139				 "ERROR: EC returned %d\n", msg.result);
140
141	r_ver = (struct ec_response_get_version *)msg.indata;
142	/* Strings should be null-terminated, but let's be sure. */
143	r_ver->version_string_ro[sizeof(r_ver->version_string_ro) - 1] = '\0';
144	r_ver->version_string_rw[sizeof(r_ver->version_string_rw) - 1] = '\0';
145	count += scnprintf(buf + count, PAGE_SIZE - count,
146			   "RO version:    %s\n", r_ver->version_string_ro);
147	count += scnprintf(buf + count, PAGE_SIZE - count,
148			   "RW version:    %s\n", r_ver->version_string_rw);
149	count += scnprintf(buf + count, PAGE_SIZE - count,
150			   "Firmware copy: %s\n",
151			   (r_ver->current_image < ARRAY_SIZE(image_names) ?
152			    image_names[r_ver->current_image] : "?"));
153
154	/* Get build info. */
155	msg.command = EC_CMD_GET_BUILD_INFO;
156	msg.insize = sizeof(msg.indata);
157	ret = cros_ec_cmd_xfer(ec, &msg);
158	if (ret < 0)
159		count += scnprintf(buf + count, PAGE_SIZE - count,
160				   "Build info:    XFER ERROR %d\n", ret);
161	else if (msg.result != EC_RES_SUCCESS)
162		count += scnprintf(buf + count, PAGE_SIZE - count,
163				   "Build info:    EC error %d\n", msg.result);
164	else {
165		msg.indata[sizeof(msg.indata) - 1] = '\0';
166		count += scnprintf(buf + count, PAGE_SIZE - count,
167				   "Build info:    %s\n", msg.indata);
168	}
169
170	/* Get chip info. */
171	msg.command = EC_CMD_GET_CHIP_INFO;
172	msg.insize = sizeof(*r_chip);
173	ret = cros_ec_cmd_xfer(ec, &msg);
174	if (ret < 0)
175		count += scnprintf(buf + count, PAGE_SIZE - count,
176				   "Chip info:     XFER ERROR %d\n", ret);
177	else if (msg.result != EC_RES_SUCCESS)
178		count += scnprintf(buf + count, PAGE_SIZE - count,
179				   "Chip info:     EC error %d\n", msg.result);
180	else {
181		r_chip = (struct ec_response_get_chip_info *)msg.indata;
182
183		r_chip->vendor[sizeof(r_chip->vendor) - 1] = '\0';
184		r_chip->name[sizeof(r_chip->name) - 1] = '\0';
185		r_chip->revision[sizeof(r_chip->revision) - 1] = '\0';
186		count += scnprintf(buf + count, PAGE_SIZE - count,
187				   "Chip vendor:   %s\n", r_chip->vendor);
188		count += scnprintf(buf + count, PAGE_SIZE - count,
189				   "Chip name:     %s\n", r_chip->name);
190		count += scnprintf(buf + count, PAGE_SIZE - count,
191				   "Chip revision: %s\n", r_chip->revision);
192	}
193
194	/* Get board version */
195	msg.command = EC_CMD_GET_BOARD_VERSION;
196	msg.insize = sizeof(*r_board);
197	ret = cros_ec_cmd_xfer(ec, &msg);
198	if (ret < 0)
199		count += scnprintf(buf + count, PAGE_SIZE - count,
200				   "Board version: XFER ERROR %d\n", ret);
201	else if (msg.result != EC_RES_SUCCESS)
202		count += scnprintf(buf + count, PAGE_SIZE - count,
203				   "Board version: EC error %d\n", msg.result);
204	else {
205		r_board = (struct ec_response_board_version *)msg.indata;
206
207		count += scnprintf(buf + count, PAGE_SIZE - count,
208				   "Board version: %d\n",
209				   r_board->board_version);
210	}
211
212	return count;
213}
214
215static ssize_t show_ec_flashinfo(struct device *dev,
216				 struct device_attribute *attr, char *buf)
217{
218	struct ec_response_flash_info *resp;
219	struct cros_ec_command msg = { 0 };
220	int ret;
221	struct cros_ec_device *ec = dev_get_drvdata(dev);
222
223	/* The flash info shouldn't ever change, but ask each time anyway. */
224	msg.command = EC_CMD_FLASH_INFO;
225	msg.insize = sizeof(*resp);
226	ret = cros_ec_cmd_xfer(ec, &msg);
227	if (ret < 0)
228		return ret;
229	if (msg.result != EC_RES_SUCCESS)
230		return scnprintf(buf, PAGE_SIZE,
231				 "ERROR: EC returned %d\n", msg.result);
232
233	resp = (struct ec_response_flash_info *)msg.indata;
234
235	return scnprintf(buf, PAGE_SIZE,
236			 "FlashSize %d\nWriteSize %d\n"
237			 "EraseSize %d\nProtectSize %d\n",
238			 resp->flash_size, resp->write_block_size,
239			 resp->erase_block_size, resp->protect_block_size);
240}
241
242/* Module initialization */
243
244static DEVICE_ATTR(reboot, S_IWUSR | S_IRUGO, show_ec_reboot, store_ec_reboot);
245static DEVICE_ATTR(version, S_IRUGO, show_ec_version, NULL);
246static DEVICE_ATTR(flashinfo, S_IRUGO, show_ec_flashinfo, NULL);
247
248static struct attribute *__ec_attrs[] = {
249	&dev_attr_reboot.attr,
250	&dev_attr_version.attr,
251	&dev_attr_flashinfo.attr,
252	NULL,
253};
254
255static struct attribute_group ec_attr_group = {
256	.attrs = __ec_attrs,
257};
258
259void ec_dev_sysfs_init(struct cros_ec_device *ec)
260{
261	int error;
262
263	error = sysfs_create_group(&ec->vdev->kobj, &ec_attr_group);
264	if (error)
265		pr_warn("failed to create group: %d\n", error);
266}
267
268void ec_dev_sysfs_remove(struct cros_ec_device *ec)
269{
270	sysfs_remove_group(&ec->vdev->kobj, &ec_attr_group);
271}
272