bna: remove oper_state_cbfn from struct bna_rxf
[linux/fpc-iii.git] / drivers / platform / chrome / cros_ec_dev.c
blob6090d0b2826fa1b9502ed47b87f10f9dd9a06a08
1 /*
2 * cros_ec_dev - expose the Chrome OS Embedded Controller to user-space
4 * Copyright (C) 2014 Google, Inc.
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.
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.
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/>.
20 #include <linux/fs.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/uaccess.h>
25 #include "cros_ec_dev.h"
27 /* Device variables */
28 #define CROS_MAX_DEV 128
29 static struct class *cros_class;
30 static int ec_major;
32 /* Basic communication */
33 static int ec_get_version(struct cros_ec_device *ec, char *str, int maxlen)
35 struct ec_response_get_version *resp;
36 static const char * const current_image_name[] = {
37 "unknown", "read-only", "read-write", "invalid",
39 struct cros_ec_command msg = {
40 .version = 0,
41 .command = EC_CMD_GET_VERSION,
42 .outdata = { 0 },
43 .outsize = 0,
44 .indata = { 0 },
45 .insize = sizeof(*resp),
47 int ret;
49 ret = cros_ec_cmd_xfer(ec, &msg);
50 if (ret < 0)
51 return ret;
53 if (msg.result != EC_RES_SUCCESS) {
54 snprintf(str, maxlen,
55 "%s\nUnknown EC version: EC returned %d\n",
56 CROS_EC_DEV_VERSION, msg.result);
57 return 0;
60 resp = (struct ec_response_get_version *)msg.indata;
61 if (resp->current_image >= ARRAY_SIZE(current_image_name))
62 resp->current_image = 3; /* invalid */
64 snprintf(str, maxlen, "%s\n%s\n%s\n%s\n", CROS_EC_DEV_VERSION,
65 resp->version_string_ro, resp->version_string_rw,
66 current_image_name[resp->current_image]);
68 return 0;
71 /* Device file ops */
72 static int ec_device_open(struct inode *inode, struct file *filp)
74 filp->private_data = container_of(inode->i_cdev,
75 struct cros_ec_device, cdev);
76 return 0;
79 static int ec_device_release(struct inode *inode, struct file *filp)
81 return 0;
84 static ssize_t ec_device_read(struct file *filp, char __user *buffer,
85 size_t length, loff_t *offset)
87 struct cros_ec_device *ec = filp->private_data;
88 char msg[sizeof(struct ec_response_get_version) +
89 sizeof(CROS_EC_DEV_VERSION)];
90 size_t count;
91 int ret;
93 if (*offset != 0)
94 return 0;
96 ret = ec_get_version(ec, msg, sizeof(msg));
97 if (ret)
98 return ret;
100 count = min(length, strlen(msg));
102 if (copy_to_user(buffer, msg, count))
103 return -EFAULT;
105 *offset = count;
106 return count;
109 /* Ioctls */
110 static long ec_device_ioctl_xcmd(struct cros_ec_device *ec, void __user *arg)
112 long ret;
113 struct cros_ec_command s_cmd = { };
115 if (copy_from_user(&s_cmd, arg, sizeof(s_cmd)))
116 return -EFAULT;
118 ret = cros_ec_cmd_xfer(ec, &s_cmd);
119 /* Only copy data to userland if data was received. */
120 if (ret < 0)
121 return ret;
123 if (copy_to_user(arg, &s_cmd, sizeof(s_cmd)))
124 return -EFAULT;
126 return 0;
129 static long ec_device_ioctl_readmem(struct cros_ec_device *ec, void __user *arg)
131 struct cros_ec_readmem s_mem = { };
132 long num;
134 /* Not every platform supports direct reads */
135 if (!ec->cmd_readmem)
136 return -ENOTTY;
138 if (copy_from_user(&s_mem, arg, sizeof(s_mem)))
139 return -EFAULT;
141 num = ec->cmd_readmem(ec, s_mem.offset, s_mem.bytes, s_mem.buffer);
142 if (num <= 0)
143 return num;
145 if (copy_to_user((void __user *)arg, &s_mem, sizeof(s_mem)))
146 return -EFAULT;
148 return 0;
151 static long ec_device_ioctl(struct file *filp, unsigned int cmd,
152 unsigned long arg)
154 struct cros_ec_device *ec = filp->private_data;
156 if (_IOC_TYPE(cmd) != CROS_EC_DEV_IOC)
157 return -ENOTTY;
159 switch (cmd) {
160 case CROS_EC_DEV_IOCXCMD:
161 return ec_device_ioctl_xcmd(ec, (void __user *)arg);
162 case CROS_EC_DEV_IOCRDMEM:
163 return ec_device_ioctl_readmem(ec, (void __user *)arg);
166 return -ENOTTY;
169 /* Module initialization */
170 static const struct file_operations fops = {
171 .open = ec_device_open,
172 .release = ec_device_release,
173 .read = ec_device_read,
174 .unlocked_ioctl = ec_device_ioctl,
177 static int ec_device_probe(struct platform_device *pdev)
179 struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
180 int retval = -ENOTTY;
181 dev_t devno = MKDEV(ec_major, 0);
183 /* Instantiate it (and remember the EC) */
184 cdev_init(&ec->cdev, &fops);
186 retval = cdev_add(&ec->cdev, devno, 1);
187 if (retval) {
188 dev_err(&pdev->dev, ": failed to add character device\n");
189 return retval;
192 ec->vdev = device_create(cros_class, NULL, devno, ec,
193 CROS_EC_DEV_NAME);
194 if (IS_ERR(ec->vdev)) {
195 retval = PTR_ERR(ec->vdev);
196 dev_err(&pdev->dev, ": failed to create device\n");
197 cdev_del(&ec->cdev);
198 return retval;
201 /* Initialize extra interfaces */
202 ec_dev_sysfs_init(ec);
203 ec_dev_lightbar_init(ec);
205 return 0;
208 static int ec_device_remove(struct platform_device *pdev)
210 struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
212 ec_dev_lightbar_remove(ec);
213 ec_dev_sysfs_remove(ec);
214 device_destroy(cros_class, MKDEV(ec_major, 0));
215 cdev_del(&ec->cdev);
216 return 0;
219 static struct platform_driver cros_ec_dev_driver = {
220 .driver = {
221 .name = "cros-ec-ctl",
223 .probe = ec_device_probe,
224 .remove = ec_device_remove,
227 static int __init cros_ec_dev_init(void)
229 int ret;
230 dev_t dev = 0;
232 cros_class = class_create(THIS_MODULE, "chromeos");
233 if (IS_ERR(cros_class)) {
234 pr_err(CROS_EC_DEV_NAME ": failed to register device class\n");
235 return PTR_ERR(cros_class);
238 /* Get a range of minor numbers (starting with 0) to work with */
239 ret = alloc_chrdev_region(&dev, 0, CROS_MAX_DEV, CROS_EC_DEV_NAME);
240 if (ret < 0) {
241 pr_err(CROS_EC_DEV_NAME ": alloc_chrdev_region() failed\n");
242 goto failed_chrdevreg;
244 ec_major = MAJOR(dev);
246 /* Register the driver */
247 ret = platform_driver_register(&cros_ec_dev_driver);
248 if (ret < 0) {
249 pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret);
250 goto failed_devreg;
252 return 0;
254 failed_devreg:
255 unregister_chrdev_region(MKDEV(ec_major, 0), CROS_MAX_DEV);
256 failed_chrdevreg:
257 class_destroy(cros_class);
258 return ret;
261 static void __exit cros_ec_dev_exit(void)
263 platform_driver_unregister(&cros_ec_dev_driver);
264 unregister_chrdev(ec_major, CROS_EC_DEV_NAME);
265 class_destroy(cros_class);
268 module_init(cros_ec_dev_init);
269 module_exit(cros_ec_dev_exit);
271 MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>");
272 MODULE_DESCRIPTION("Userspace interface to the Chrome OS Embedded Controller");
273 MODULE_VERSION("1.0");
274 MODULE_LICENSE("GPL");