1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * cec - HDMI Consumer Electronics Control support header
5 * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
11 #include <linux/poll.h>
13 #include <linux/debugfs.h>
14 #include <linux/device.h>
15 #include <linux/cdev.h>
16 #include <linux/kthread.h>
17 #include <linux/timer.h>
18 #include <linux/cec-funcs.h>
19 #include <media/rc-core.h>
21 /* CEC_ADAP_G_CONNECTOR_INFO is available */
22 #define CEC_CAP_CONNECTOR_INFO (1 << 8)
24 #define CEC_CAP_DEFAULTS (CEC_CAP_LOG_ADDRS | CEC_CAP_TRANSMIT | \
25 CEC_CAP_PASSTHROUGH | CEC_CAP_RC)
28 * struct cec_devnode - cec device node
30 * @cdev: cec character device
31 * @minor: device node minor number
32 * @registered: the device was correctly registered
33 * @unregistered: the device was unregistered
34 * @fhs_lock: lock to control access to the filehandle list
35 * @fhs: the list of open filehandles (cec_fh)
37 * This structure represents a cec-related device node.
39 * The @parent is a physical device. It must be set by core or device drivers
40 * before registering the node.
61 struct list_head list
;
62 struct list_head xfer_list
;
63 struct cec_adapter
*adap
;
66 struct delayed_work work
;
73 struct cec_msg_entry
{
74 struct list_head list
;
78 struct cec_event_entry
{
79 struct list_head list
;
83 #define CEC_NUM_CORE_EVENTS 2
84 #define CEC_NUM_EVENTS CEC_EVENT_PIN_5V_HIGH
87 struct list_head list
;
88 struct list_head xfer_list
;
89 struct cec_adapter
*adap
;
94 wait_queue_head_t wait
;
96 struct list_head events
[CEC_NUM_EVENTS
]; /* queued events */
97 u16 queued_events
[CEC_NUM_EVENTS
];
98 unsigned int total_queued_events
;
99 struct cec_event_entry core_events
[CEC_NUM_CORE_EVENTS
];
100 struct list_head msgs
; /* queued messages */
101 unsigned int queued_msgs
;
104 #define CEC_SIGNAL_FREE_TIME_RETRY 3
105 #define CEC_SIGNAL_FREE_TIME_NEW_INITIATOR 5
106 #define CEC_SIGNAL_FREE_TIME_NEXT_XFER 7
108 /* The nominal data bit period is 2.4 ms */
109 #define CEC_FREE_TIME_TO_USEC(ft) ((ft) * 2400)
111 struct cec_adap_ops
{
112 /* Low-level callbacks */
113 int (*adap_enable
)(struct cec_adapter
*adap
, bool enable
);
114 int (*adap_monitor_all_enable
)(struct cec_adapter
*adap
, bool enable
);
115 int (*adap_monitor_pin_enable
)(struct cec_adapter
*adap
, bool enable
);
116 int (*adap_log_addr
)(struct cec_adapter
*adap
, u8 logical_addr
);
117 int (*adap_transmit
)(struct cec_adapter
*adap
, u8 attempts
,
118 u32 signal_free_time
, struct cec_msg
*msg
);
119 void (*adap_status
)(struct cec_adapter
*adap
, struct seq_file
*file
);
120 void (*adap_free
)(struct cec_adapter
*adap
);
122 /* Error injection callbacks */
123 int (*error_inj_show
)(struct cec_adapter
*adap
, struct seq_file
*sf
);
124 bool (*error_inj_parse_line
)(struct cec_adapter
*adap
, char *line
);
126 /* High-level CEC message callback */
127 int (*received
)(struct cec_adapter
*adap
, struct cec_msg
*msg
);
131 * The minimum message length you can receive (excepting poll messages) is 2.
132 * With a transfer rate of at most 36 bytes per second this makes 18 messages
133 * per second worst case.
135 * We queue at most 3 seconds worth of received messages. The CEC specification
136 * requires that messages are replied to within a second, so 3 seconds should
137 * give more than enough margin. Since most messages are actually more than 2
138 * bytes, this is in practice a lot more than 3 seconds.
140 #define CEC_MAX_MSG_RX_QUEUE_SZ (18 * 3)
143 * The transmit queue is limited to 1 second worth of messages (worst case).
144 * Messages can be transmitted by userspace and kernel space. But for both it
145 * makes no sense to have a lot of messages queued up. One second seems
148 #define CEC_MAX_MSG_TX_QUEUE_SZ (18 * 1)
151 * struct cec_drm_connector_info - tells which drm connector is
152 * associated with the CEC adapter.
153 * @card_no: drm card number
154 * @connector_id: drm connector ID
156 struct cec_drm_connector_info
{
161 #define CEC_CONNECTOR_TYPE_NO_CONNECTOR 0
162 #define CEC_CONNECTOR_TYPE_DRM 1
165 * struct cec_connector_info - tells if and which connector is
166 * associated with the CEC adapter.
167 * @type: connector type (if any)
168 * @drm: drm connector info
170 struct cec_connector_info
{
173 struct cec_drm_connector_info drm
;
179 struct module
*owner
;
181 struct cec_devnode devnode
;
185 struct list_head transmit_queue
;
186 unsigned int transmit_queue_sz
;
187 struct list_head wait_queue
;
188 struct cec_data
*transmitting
;
189 bool transmit_in_progress
;
191 struct task_struct
*kthread_config
;
192 struct completion config_completion
;
194 struct task_struct
*kthread
;
195 wait_queue_head_t kthread_waitq
;
196 wait_queue_head_t waitq
;
198 const struct cec_adap_ops
*ops
;
201 u8 available_log_addrs
;
207 bool cec_pin_is_high
;
212 struct cec_fh
*cec_follower
;
213 struct cec_fh
*cec_initiator
;
215 struct cec_log_addrs log_addrs
;
216 struct cec_connector_info conn_info
;
220 #ifdef CONFIG_CEC_NOTIFIER
221 struct cec_notifier
*notifier
;
223 #ifdef CONFIG_CEC_PIN
227 struct dentry
*cec_dir
;
228 struct dentry
*status_file
;
229 struct dentry
*error_inj_file
;
237 static inline void *cec_get_drvdata(const struct cec_adapter
*adap
)
242 static inline bool cec_has_log_addr(const struct cec_adapter
*adap
, u8 log_addr
)
244 return adap
->log_addrs
.log_addr_mask
& (1 << log_addr
);
247 static inline bool cec_is_sink(const struct cec_adapter
*adap
)
249 return adap
->phys_addr
== 0;
253 * cec_is_registered() - is the CEC adapter registered?
255 * @adap: the CEC adapter, may be NULL.
257 * Return: true if the adapter is registered, false otherwise.
259 static inline bool cec_is_registered(const struct cec_adapter
*adap
)
261 return adap
&& adap
->devnode
.registered
;
264 #define cec_phys_addr_exp(pa) \
265 ((pa) >> 12), ((pa) >> 8) & 0xf, ((pa) >> 4) & 0xf, (pa) & 0xf
268 struct drm_connector
;
270 #if IS_REACHABLE(CONFIG_CEC_CORE)
271 struct cec_adapter
*cec_allocate_adapter(const struct cec_adap_ops
*ops
,
272 void *priv
, const char *name
, u32 caps
, u8 available_las
);
273 int cec_register_adapter(struct cec_adapter
*adap
, struct device
*parent
);
274 void cec_unregister_adapter(struct cec_adapter
*adap
);
275 void cec_delete_adapter(struct cec_adapter
*adap
);
277 int cec_s_log_addrs(struct cec_adapter
*adap
, struct cec_log_addrs
*log_addrs
,
279 void cec_s_phys_addr(struct cec_adapter
*adap
, u16 phys_addr
,
281 void cec_s_phys_addr_from_edid(struct cec_adapter
*adap
,
282 const struct edid
*edid
);
283 void cec_s_conn_info(struct cec_adapter
*adap
,
284 const struct cec_connector_info
*conn_info
);
285 int cec_transmit_msg(struct cec_adapter
*adap
, struct cec_msg
*msg
,
288 /* Called by the adapter */
289 void cec_transmit_done_ts(struct cec_adapter
*adap
, u8 status
,
290 u8 arb_lost_cnt
, u8 nack_cnt
, u8 low_drive_cnt
,
291 u8 error_cnt
, ktime_t ts
);
293 static inline void cec_transmit_done(struct cec_adapter
*adap
, u8 status
,
294 u8 arb_lost_cnt
, u8 nack_cnt
,
295 u8 low_drive_cnt
, u8 error_cnt
)
297 cec_transmit_done_ts(adap
, status
, arb_lost_cnt
, nack_cnt
,
298 low_drive_cnt
, error_cnt
, ktime_get());
301 * Simplified version of cec_transmit_done for hardware that doesn't retry
302 * failed transmits. So this is always just one attempt in which case
303 * the status is sufficient.
305 void cec_transmit_attempt_done_ts(struct cec_adapter
*adap
,
306 u8 status
, ktime_t ts
);
308 static inline void cec_transmit_attempt_done(struct cec_adapter
*adap
,
311 cec_transmit_attempt_done_ts(adap
, status
, ktime_get());
314 void cec_received_msg_ts(struct cec_adapter
*adap
,
315 struct cec_msg
*msg
, ktime_t ts
);
317 static inline void cec_received_msg(struct cec_adapter
*adap
,
320 cec_received_msg_ts(adap
, msg
, ktime_get());
324 * cec_queue_pin_cec_event() - queue a CEC pin event with a given timestamp.
326 * @adap: pointer to the cec adapter
327 * @is_high: when true the CEC pin is high, otherwise it is low
328 * @dropped_events: when true some events were dropped
329 * @ts: the timestamp for this event
332 void cec_queue_pin_cec_event(struct cec_adapter
*adap
, bool is_high
,
333 bool dropped_events
, ktime_t ts
);
336 * cec_queue_pin_hpd_event() - queue a pin event with a given timestamp.
338 * @adap: pointer to the cec adapter
339 * @is_high: when true the HPD pin is high, otherwise it is low
340 * @ts: the timestamp for this event
343 void cec_queue_pin_hpd_event(struct cec_adapter
*adap
, bool is_high
, ktime_t ts
);
346 * cec_queue_pin_5v_event() - queue a pin event with a given timestamp.
348 * @adap: pointer to the cec adapter
349 * @is_high: when true the 5V pin is high, otherwise it is low
350 * @ts: the timestamp for this event
353 void cec_queue_pin_5v_event(struct cec_adapter
*adap
, bool is_high
, ktime_t ts
);
356 * cec_get_edid_phys_addr() - find and return the physical address
358 * @edid: pointer to the EDID data
359 * @size: size in bytes of the EDID data
360 * @offset: If not %NULL then the location of the physical address
361 * bytes in the EDID will be returned here. This is set to 0
362 * if there is no physical address found.
364 * Return: the physical address or CEC_PHYS_ADDR_INVALID if there is none.
366 u16
cec_get_edid_phys_addr(const u8
*edid
, unsigned int size
,
367 unsigned int *offset
);
369 void cec_fill_conn_info_from_drm(struct cec_connector_info
*conn_info
,
370 const struct drm_connector
*connector
);
374 static inline int cec_register_adapter(struct cec_adapter
*adap
,
375 struct device
*parent
)
380 static inline void cec_unregister_adapter(struct cec_adapter
*adap
)
384 static inline void cec_delete_adapter(struct cec_adapter
*adap
)
388 static inline void cec_s_phys_addr(struct cec_adapter
*adap
, u16 phys_addr
,
393 static inline void cec_s_phys_addr_from_edid(struct cec_adapter
*adap
,
394 const struct edid
*edid
)
398 static inline u16
cec_get_edid_phys_addr(const u8
*edid
, unsigned int size
,
399 unsigned int *offset
)
403 return CEC_PHYS_ADDR_INVALID
;
406 static inline void cec_s_conn_info(struct cec_adapter
*adap
,
407 const struct cec_connector_info
*conn_info
)
412 cec_fill_conn_info_from_drm(struct cec_connector_info
*conn_info
,
413 const struct drm_connector
*connector
)
415 memset(conn_info
, 0, sizeof(*conn_info
));
420 #if IS_REACHABLE(CONFIG_CEC_CORE) && IS_ENABLED(CONFIG_CEC_NOTIFIER)
423 * cec_notifier_register - register a callback with the notifier
424 * @n: the CEC notifier
425 * @adap: the CEC adapter, passed as argument to the callback function
426 * @callback: the callback function
428 void cec_notifier_register(struct cec_notifier
*n
,
429 struct cec_adapter
*adap
,
430 void (*callback
)(struct cec_adapter
*adap
, u16 pa
));
433 * cec_notifier_unregister - unregister the callback from the notifier.
434 * @n: the CEC notifier
436 void cec_notifier_unregister(struct cec_notifier
*n
);
439 * cec_register_cec_notifier - register the notifier with the cec adapter.
440 * @adap: the CEC adapter
441 * @notifier: the CEC notifier
443 void cec_register_cec_notifier(struct cec_adapter
*adap
,
444 struct cec_notifier
*notifier
);
449 cec_notifier_register(struct cec_notifier
*n
,
450 struct cec_adapter
*adap
,
451 void (*callback
)(struct cec_adapter
*adap
, u16 pa
))
455 static inline void cec_notifier_unregister(struct cec_notifier
*n
)
459 static inline void cec_register_cec_notifier(struct cec_adapter
*adap
,
460 struct cec_notifier
*notifier
)
467 * cec_phys_addr_invalidate() - set the physical address to INVALID
469 * @adap: the CEC adapter
471 * This is a simple helper function to invalidate the physical
474 static inline void cec_phys_addr_invalidate(struct cec_adapter
*adap
)
476 cec_s_phys_addr(adap
, CEC_PHYS_ADDR_INVALID
, false);
480 * cec_get_edid_spa_location() - find location of the Source Physical Address
483 * @size: the size of the EDID
485 * This EDID is expected to be a CEA-861 compliant, which means that there are
486 * at least two blocks and one or more of the extensions blocks are CEA-861
489 * The returned location is guaranteed to be <= size-2.
491 * This is an inline function since it is used by both CEC and V4L2.
492 * Ideally this would go in a module shared by both, but it is overkill to do
493 * that for just a single function.
495 static inline unsigned int cec_get_edid_spa_location(const u8
*edid
,
498 unsigned int blocks
= size
/ 128;
502 /* Sanity check: at least 2 blocks and a multiple of the block size */
503 if (blocks
< 2 || size
% 128)
507 * If there are fewer extension blocks than the size, then update
508 * 'blocks'. It is allowed to have more extension blocks than the size,
509 * since some hardware can only read e.g. 256 bytes of the EDID, even
510 * though more blocks are present. The first CEA-861 extension block
511 * should normally be in block 1 anyway.
513 if (edid
[0x7e] + 1 < blocks
)
514 blocks
= edid
[0x7e] + 1;
516 for (block
= 1; block
< blocks
; block
++) {
517 unsigned int offset
= block
* 128;
519 /* Skip any non-CEA-861 extension blocks */
520 if (edid
[offset
] != 0x02 || edid
[offset
+ 1] != 0x03)
523 /* search Vendor Specific Data Block (tag 3) */
524 d
= edid
[offset
+ 2] & 0x7f;
525 /* Check if there are Data Blocks */
529 unsigned int i
= offset
+ 4;
530 unsigned int end
= offset
+ d
;
532 /* Note: 'end' is always < 'size' */
534 u8 tag
= edid
[i
] >> 5;
535 u8 len
= edid
[i
] & 0x1f;
537 if (tag
== 3 && len
>= 5 && i
+ len
<= end
&&
538 edid
[i
+ 1] == 0x03 &&
539 edid
[i
+ 2] == 0x0c &&
549 #endif /* _MEDIA_CEC_H */