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8#include <linux/errno.h>
9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/kmod.h>
13#include <linux/slab.h>
14#include <linux/mm.h>
15#include <linux/string.h>
16#include <linux/types.h>
17
18#include "cec-priv.h"
19
20#define CEC_NUM_DEVICES 256
21#define CEC_NAME "cec"
22
23int cec_debug;
24module_param_named(debug, cec_debug, int, 0644);
25MODULE_PARM_DESC(debug, "debug level (0-2)");
26
27static bool debug_phys_addr;
28module_param(debug_phys_addr, bool, 0644);
29MODULE_PARM_DESC(debug_phys_addr, "add CEC_CAP_PHYS_ADDR if set");
30
31static dev_t cec_dev_t;
32
33
34static DEFINE_MUTEX(cec_devnode_lock);
35static DECLARE_BITMAP(cec_devnode_nums, CEC_NUM_DEVICES);
36
37static struct dentry *top_cec_dir;
38
39
40#define to_cec_devnode(cd) container_of(cd, struct cec_devnode, dev)
41
42int cec_get_device(struct cec_devnode *devnode)
43{
44
45
46
47
48
49
50
51 mutex_lock(&devnode->lock);
52
53
54
55
56 if (!devnode->registered) {
57 mutex_unlock(&devnode->lock);
58 return -ENXIO;
59 }
60
61 get_device(&devnode->dev);
62 mutex_unlock(&devnode->lock);
63 return 0;
64}
65
66void cec_put_device(struct cec_devnode *devnode)
67{
68 put_device(&devnode->dev);
69}
70
71
72static void cec_devnode_release(struct device *cd)
73{
74 struct cec_devnode *devnode = to_cec_devnode(cd);
75
76 mutex_lock(&cec_devnode_lock);
77
78 clear_bit(devnode->minor, cec_devnode_nums);
79 mutex_unlock(&cec_devnode_lock);
80
81 cec_delete_adapter(to_cec_adapter(devnode));
82}
83
84static struct bus_type cec_bus_type = {
85 .name = CEC_NAME,
86};
87
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100
101static int __must_check cec_devnode_register(struct cec_devnode *devnode,
102 struct module *owner)
103{
104 int minor;
105 int ret;
106
107
108 mutex_lock(&cec_devnode_lock);
109 minor = find_next_zero_bit(cec_devnode_nums, CEC_NUM_DEVICES, 0);
110 if (minor == CEC_NUM_DEVICES) {
111 mutex_unlock(&cec_devnode_lock);
112 pr_err("could not get a free minor\n");
113 return -ENFILE;
114 }
115
116 set_bit(minor, cec_devnode_nums);
117 mutex_unlock(&cec_devnode_lock);
118
119 devnode->minor = minor;
120 devnode->dev.bus = &cec_bus_type;
121 devnode->dev.devt = MKDEV(MAJOR(cec_dev_t), minor);
122 devnode->dev.release = cec_devnode_release;
123 dev_set_name(&devnode->dev, "cec%d", devnode->minor);
124 device_initialize(&devnode->dev);
125
126
127 cdev_init(&devnode->cdev, &cec_devnode_fops);
128 devnode->cdev.owner = owner;
129 kobject_set_name(&devnode->cdev.kobj, "cec%d", devnode->minor);
130
131 devnode->registered = true;
132 ret = cdev_device_add(&devnode->cdev, &devnode->dev);
133 if (ret) {
134 devnode->registered = false;
135 pr_err("%s: cdev_device_add failed\n", __func__);
136 goto clr_bit;
137 }
138
139 return 0;
140
141clr_bit:
142 mutex_lock(&cec_devnode_lock);
143 clear_bit(devnode->minor, cec_devnode_nums);
144 mutex_unlock(&cec_devnode_lock);
145 return ret;
146}
147
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151
152
153
154
155
156
157static void cec_devnode_unregister(struct cec_adapter *adap)
158{
159 struct cec_devnode *devnode = &adap->devnode;
160 struct cec_fh *fh;
161
162 mutex_lock(&devnode->lock);
163
164
165 if (!devnode->registered || devnode->unregistered) {
166 mutex_unlock(&devnode->lock);
167 return;
168 }
169 devnode->registered = false;
170 devnode->unregistered = true;
171
172 list_for_each_entry(fh, &devnode->fhs, list)
173 wake_up_interruptible(&fh->wait);
174
175 mutex_unlock(&devnode->lock);
176
177 mutex_lock(&adap->lock);
178 __cec_s_phys_addr(adap, CEC_PHYS_ADDR_INVALID, false);
179 __cec_s_log_addrs(adap, NULL, false);
180 mutex_unlock(&adap->lock);
181
182 cdev_device_del(&devnode->cdev, &devnode->dev);
183 put_device(&devnode->dev);
184}
185
186#ifdef CONFIG_DEBUG_FS
187static ssize_t cec_error_inj_write(struct file *file,
188 const char __user *ubuf, size_t count, loff_t *ppos)
189{
190 struct seq_file *sf = file->private_data;
191 struct cec_adapter *adap = sf->private;
192 char *buf;
193 char *line;
194 char *p;
195
196 buf = memdup_user_nul(ubuf, min_t(size_t, PAGE_SIZE, count));
197 if (IS_ERR(buf))
198 return PTR_ERR(buf);
199 p = buf;
200 while (p && *p) {
201 p = skip_spaces(p);
202 line = strsep(&p, "\n");
203 if (!*line || *line == '#')
204 continue;
205 if (!adap->ops->error_inj_parse_line(adap, line)) {
206 kfree(buf);
207 return -EINVAL;
208 }
209 }
210 kfree(buf);
211 return count;
212}
213
214static int cec_error_inj_show(struct seq_file *sf, void *unused)
215{
216 struct cec_adapter *adap = sf->private;
217
218 return adap->ops->error_inj_show(adap, sf);
219}
220
221static int cec_error_inj_open(struct inode *inode, struct file *file)
222{
223 return single_open(file, cec_error_inj_show, inode->i_private);
224}
225
226static const struct file_operations cec_error_inj_fops = {
227 .open = cec_error_inj_open,
228 .write = cec_error_inj_write,
229 .read = seq_read,
230 .llseek = seq_lseek,
231 .release = single_release,
232};
233#endif
234
235struct cec_adapter *cec_allocate_adapter(const struct cec_adap_ops *ops,
236 void *priv, const char *name, u32 caps,
237 u8 available_las)
238{
239 struct cec_adapter *adap;
240 int res;
241
242#ifndef CONFIG_MEDIA_CEC_RC
243 caps &= ~CEC_CAP_RC;
244#endif
245
246 if (WARN_ON(!caps))
247 return ERR_PTR(-EINVAL);
248 if (WARN_ON(!ops))
249 return ERR_PTR(-EINVAL);
250 if (WARN_ON(!available_las || available_las > CEC_MAX_LOG_ADDRS))
251 return ERR_PTR(-EINVAL);
252 adap = kzalloc(sizeof(*adap), GFP_KERNEL);
253 if (!adap)
254 return ERR_PTR(-ENOMEM);
255 strscpy(adap->name, name, sizeof(adap->name));
256 adap->phys_addr = CEC_PHYS_ADDR_INVALID;
257 adap->cec_pin_is_high = true;
258 adap->log_addrs.cec_version = CEC_OP_CEC_VERSION_2_0;
259 adap->log_addrs.vendor_id = CEC_VENDOR_ID_NONE;
260 adap->capabilities = caps;
261 if (debug_phys_addr)
262 adap->capabilities |= CEC_CAP_PHYS_ADDR;
263 adap->needs_hpd = caps & CEC_CAP_NEEDS_HPD;
264 adap->available_log_addrs = available_las;
265 adap->sequence = 0;
266 adap->ops = ops;
267 adap->priv = priv;
268 mutex_init(&adap->lock);
269 INIT_LIST_HEAD(&adap->transmit_queue);
270 INIT_LIST_HEAD(&adap->wait_queue);
271 init_waitqueue_head(&adap->kthread_waitq);
272
273
274 INIT_LIST_HEAD(&adap->devnode.fhs);
275 mutex_init(&adap->devnode.lock);
276
277 adap->kthread = kthread_run(cec_thread_func, adap, "cec-%s", name);
278 if (IS_ERR(adap->kthread)) {
279 pr_err("cec-%s: kernel_thread() failed\n", name);
280 res = PTR_ERR(adap->kthread);
281 kfree(adap);
282 return ERR_PTR(res);
283 }
284
285#ifdef CONFIG_MEDIA_CEC_RC
286 if (!(caps & CEC_CAP_RC))
287 return adap;
288
289
290 adap->rc = rc_allocate_device(RC_DRIVER_SCANCODE);
291 if (!adap->rc) {
292 pr_err("cec-%s: failed to allocate memory for rc_dev\n",
293 name);
294 kthread_stop(adap->kthread);
295 kfree(adap);
296 return ERR_PTR(-ENOMEM);
297 }
298
299 snprintf(adap->input_phys, sizeof(adap->input_phys),
300 "%s/input0", adap->name);
301
302 adap->rc->device_name = adap->name;
303 adap->rc->input_phys = adap->input_phys;
304 adap->rc->input_id.bustype = BUS_CEC;
305 adap->rc->input_id.vendor = 0;
306 adap->rc->input_id.product = 0;
307 adap->rc->input_id.version = 1;
308 adap->rc->driver_name = CEC_NAME;
309 adap->rc->allowed_protocols = RC_PROTO_BIT_CEC;
310 adap->rc->priv = adap;
311 adap->rc->map_name = RC_MAP_CEC;
312 adap->rc->timeout = MS_TO_US(550);
313#endif
314 return adap;
315}
316EXPORT_SYMBOL_GPL(cec_allocate_adapter);
317
318int cec_register_adapter(struct cec_adapter *adap,
319 struct device *parent)
320{
321 int res;
322
323 if (IS_ERR_OR_NULL(adap))
324 return 0;
325
326 if (WARN_ON(!parent))
327 return -EINVAL;
328
329 adap->owner = parent->driver->owner;
330 adap->devnode.dev.parent = parent;
331
332#ifdef CONFIG_MEDIA_CEC_RC
333 if (adap->capabilities & CEC_CAP_RC) {
334 adap->rc->dev.parent = parent;
335 res = rc_register_device(adap->rc);
336
337 if (res) {
338 pr_err("cec-%s: failed to prepare input device\n",
339 adap->name);
340 rc_free_device(adap->rc);
341 adap->rc = NULL;
342 return res;
343 }
344 }
345#endif
346
347 res = cec_devnode_register(&adap->devnode, adap->owner);
348 if (res) {
349#ifdef CONFIG_MEDIA_CEC_RC
350
351 rc_unregister_device(adap->rc);
352 adap->rc = NULL;
353#endif
354 return res;
355 }
356
357 dev_set_drvdata(&adap->devnode.dev, adap);
358#ifdef CONFIG_DEBUG_FS
359 if (!top_cec_dir)
360 return 0;
361
362 adap->cec_dir = debugfs_create_dir(dev_name(&adap->devnode.dev),
363 top_cec_dir);
364
365 debugfs_create_devm_seqfile(&adap->devnode.dev, "status", adap->cec_dir,
366 cec_adap_status);
367
368 if (!adap->ops->error_inj_show || !adap->ops->error_inj_parse_line)
369 return 0;
370 debugfs_create_file("error-inj", 0644, adap->cec_dir, adap,
371 &cec_error_inj_fops);
372#endif
373 return 0;
374}
375EXPORT_SYMBOL_GPL(cec_register_adapter);
376
377void cec_unregister_adapter(struct cec_adapter *adap)
378{
379 if (IS_ERR_OR_NULL(adap))
380 return;
381
382#ifdef CONFIG_MEDIA_CEC_RC
383
384 rc_unregister_device(adap->rc);
385 adap->rc = NULL;
386#endif
387 debugfs_remove_recursive(adap->cec_dir);
388#ifdef CONFIG_CEC_NOTIFIER
389 cec_notifier_cec_adap_unregister(adap->notifier, adap);
390#endif
391 cec_devnode_unregister(adap);
392}
393EXPORT_SYMBOL_GPL(cec_unregister_adapter);
394
395void cec_delete_adapter(struct cec_adapter *adap)
396{
397 if (IS_ERR_OR_NULL(adap))
398 return;
399 if (adap->kthread_config)
400 kthread_stop(adap->kthread_config);
401 kthread_stop(adap->kthread);
402 if (adap->ops->adap_free)
403 adap->ops->adap_free(adap);
404#ifdef CONFIG_MEDIA_CEC_RC
405 rc_free_device(adap->rc);
406#endif
407 kfree(adap);
408}
409EXPORT_SYMBOL_GPL(cec_delete_adapter);
410
411
412
413
414static int __init cec_devnode_init(void)
415{
416 int ret = alloc_chrdev_region(&cec_dev_t, 0, CEC_NUM_DEVICES, CEC_NAME);
417
418 if (ret < 0) {
419 pr_warn("cec: unable to allocate major\n");
420 return ret;
421 }
422
423#ifdef CONFIG_DEBUG_FS
424 top_cec_dir = debugfs_create_dir("cec", NULL);
425 if (IS_ERR_OR_NULL(top_cec_dir)) {
426 pr_warn("cec: Failed to create debugfs cec dir\n");
427 top_cec_dir = NULL;
428 }
429#endif
430
431 ret = bus_register(&cec_bus_type);
432 if (ret < 0) {
433 unregister_chrdev_region(cec_dev_t, CEC_NUM_DEVICES);
434 pr_warn("cec: bus_register failed\n");
435 return -EIO;
436 }
437
438 return 0;
439}
440
441static void __exit cec_devnode_exit(void)
442{
443 debugfs_remove_recursive(top_cec_dir);
444 bus_unregister(&cec_bus_type);
445 unregister_chrdev_region(cec_dev_t, CEC_NUM_DEVICES);
446}
447
448subsys_initcall(cec_devnode_init);
449module_exit(cec_devnode_exit)
450
451MODULE_AUTHOR("Hans Verkuil <hans.verkuil@cisco.com>");
452MODULE_DESCRIPTION("Device node registration for cec drivers");
453MODULE_LICENSE("GPL");
454
