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Diffstat (limited to 'include/media/cec.h')
| -rw-r--r-- | include/media/cec.h | 547 |
1 files changed, 547 insertions, 0 deletions
diff --git a/include/media/cec.h b/include/media/cec.h new file mode 100644 index 000000000..9c007f835 --- /dev/null +++ b/include/media/cec.h @@ -0,0 +1,547 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * cec - HDMI Consumer Electronics Control support header + * + * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + */ + +#ifndef _MEDIA_CEC_H +#define _MEDIA_CEC_H + +#include <linux/poll.h> +#include <linux/fs.h> +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/cdev.h> +#include <linux/kthread.h> +#include <linux/timer.h> +#include <linux/cec-funcs.h> +#include <media/rc-core.h> + +#define CEC_CAP_DEFAULTS (CEC_CAP_LOG_ADDRS | CEC_CAP_TRANSMIT | \ + CEC_CAP_PASSTHROUGH | CEC_CAP_RC) + +/** + * struct cec_devnode - cec device node + * @dev: cec device + * @cdev: cec character device + * @minor: device node minor number + * @lock: lock to serialize open/release and registration + * @registered: the device was correctly registered + * @unregistered: the device was unregistered + * @lock_fhs: lock to control access to @fhs + * @fhs: the list of open filehandles (cec_fh) + * + * This structure represents a cec-related device node. + * + * To add or remove filehandles from @fhs the @lock must be taken first, + * followed by @lock_fhs. It is safe to access @fhs if either lock is held. + * + * The @parent is a physical device. It must be set by core or device drivers + * before registering the node. + */ +struct cec_devnode { + /* sysfs */ + struct device dev; + struct cdev cdev; + + /* device info */ + int minor; + /* serialize open/release and registration */ + struct mutex lock; + bool registered; + bool unregistered; + /* protect access to fhs */ + struct mutex lock_fhs; + struct list_head fhs; +}; + +struct cec_adapter; +struct cec_data; +struct cec_pin; +struct cec_notifier; + +struct cec_data { + struct list_head list; + struct list_head xfer_list; + struct cec_adapter *adap; + struct cec_msg msg; + struct cec_fh *fh; + struct delayed_work work; + struct completion c; + u8 attempts; + bool blocking; + bool completed; +}; + +struct cec_msg_entry { + struct list_head list; + struct cec_msg msg; +}; + +struct cec_event_entry { + struct list_head list; + struct cec_event ev; +}; + +#define CEC_NUM_CORE_EVENTS 2 +#define CEC_NUM_EVENTS CEC_EVENT_PIN_5V_HIGH + +struct cec_fh { + struct list_head list; + struct list_head xfer_list; + struct cec_adapter *adap; + u8 mode_initiator; + u8 mode_follower; + + /* Events */ + wait_queue_head_t wait; + struct mutex lock; + struct list_head events[CEC_NUM_EVENTS]; /* queued events */ + u16 queued_events[CEC_NUM_EVENTS]; + unsigned int total_queued_events; + struct cec_event_entry core_events[CEC_NUM_CORE_EVENTS]; + struct list_head msgs; /* queued messages */ + unsigned int queued_msgs; +}; + +#define CEC_SIGNAL_FREE_TIME_RETRY 3 +#define CEC_SIGNAL_FREE_TIME_NEW_INITIATOR 5 +#define CEC_SIGNAL_FREE_TIME_NEXT_XFER 7 + +/* The nominal data bit period is 2.4 ms */ +#define CEC_FREE_TIME_TO_USEC(ft) ((ft) * 2400) + +struct cec_adap_ops { + /* Low-level callbacks, called with adap->lock held */ + int (*adap_enable)(struct cec_adapter *adap, bool enable); + int (*adap_monitor_all_enable)(struct cec_adapter *adap, bool enable); + int (*adap_monitor_pin_enable)(struct cec_adapter *adap, bool enable); + int (*adap_log_addr)(struct cec_adapter *adap, u8 logical_addr); + void (*adap_unconfigured)(struct cec_adapter *adap); + int (*adap_transmit)(struct cec_adapter *adap, u8 attempts, + u32 signal_free_time, struct cec_msg *msg); + void (*adap_nb_transmit_canceled)(struct cec_adapter *adap, + const struct cec_msg *msg); + void (*adap_status)(struct cec_adapter *adap, struct seq_file *file); + void (*adap_free)(struct cec_adapter *adap); + + /* Error injection callbacks, called without adap->lock held */ + int (*error_inj_show)(struct cec_adapter *adap, struct seq_file *sf); + bool (*error_inj_parse_line)(struct cec_adapter *adap, char *line); + + /* High-level CEC message callback, called without adap->lock held */ + void (*configured)(struct cec_adapter *adap); + int (*received)(struct cec_adapter *adap, struct cec_msg *msg); +}; + +/* + * The minimum message length you can receive (excepting poll messages) is 2. + * With a transfer rate of at most 36 bytes per second this makes 18 messages + * per second worst case. + * + * We queue at most 3 seconds worth of received messages. The CEC specification + * requires that messages are replied to within a second, so 3 seconds should + * give more than enough margin. Since most messages are actually more than 2 + * bytes, this is in practice a lot more than 3 seconds. + */ +#define CEC_MAX_MSG_RX_QUEUE_SZ (18 * 3) + +/* + * The transmit queue is limited to 1 second worth of messages (worst case). + * Messages can be transmitted by userspace and kernel space. But for both it + * makes no sense to have a lot of messages queued up. One second seems + * reasonable. + */ +#define CEC_MAX_MSG_TX_QUEUE_SZ (18 * 1) + +/** + * struct cec_adapter - cec adapter structure + * @owner: module owner + * @name: name of the CEC adapter + * @devnode: device node for the /dev/cecX device + * @lock: mutex controlling access to this structure + * @rc: remote control device + * @transmit_queue: queue of pending transmits + * @transmit_queue_sz: number of pending transmits + * @wait_queue: queue of transmits waiting for a reply + * @transmitting: CEC messages currently being transmitted + * @transmit_in_progress: true if a transmit is in progress + * @transmit_in_progress_aborted: true if a transmit is in progress is to be + * aborted. This happens if the logical address is + * invalidated while the transmit is ongoing. In that + * case the transmit will finish, but will not retransmit + * and be marked as ABORTED. + * @xfer_timeout_ms: the transfer timeout in ms. + * If 0, then timeout after 2.1 ms. + * @kthread_config: kthread used to configure a CEC adapter + * @config_completion: used to signal completion of the config kthread + * @kthread: main CEC processing thread + * @kthread_waitq: main CEC processing wait_queue + * @ops: cec adapter ops + * @priv: cec driver's private data + * @capabilities: cec adapter capabilities + * @available_log_addrs: maximum number of available logical addresses + * @phys_addr: the current physical address + * @needs_hpd: if true, then the HDMI HotPlug Detect pin must be high + * in order to transmit or receive CEC messages. This is usually a HW + * limitation. + * @is_enabled: the CEC adapter is enabled + * @is_configuring: the CEC adapter is configuring (i.e. claiming LAs) + * @must_reconfigure: while configuring, the PA changed, so reclaim LAs + * @is_configured: the CEC adapter is configured (i.e. has claimed LAs) + * @cec_pin_is_high: if true then the CEC pin is high. Only used with the + * CEC pin framework. + * @adap_controls_phys_addr: if true, then the CEC adapter controls the + * physical address, i.e. the CEC hardware can detect HPD changes and + * read the EDID and is not dependent on an external HDMI driver. + * Drivers that need this can set this field to true after the + * cec_allocate_adapter() call. + * @last_initiator: the initiator of the last transmitted message. + * @monitor_all_cnt: number of filehandles monitoring all msgs + * @monitor_pin_cnt: number of filehandles monitoring pin changes + * @follower_cnt: number of filehandles in follower mode + * @cec_follower: filehandle of the exclusive follower + * @cec_initiator: filehandle of the exclusive initiator + * @passthrough: if true, then the exclusive follower is in + * passthrough mode. + * @log_addrs: current logical addresses + * @conn_info: current connector info + * @tx_timeouts: number of transmit timeouts + * @notifier: CEC notifier + * @pin: CEC pin status struct + * @cec_dir: debugfs cec directory + * @status_file: debugfs cec status file + * @error_inj_file: debugfs cec error injection file + * @sequence: transmit sequence counter + * @input_phys: remote control input_phys name + * + * This structure represents a cec adapter. + */ +struct cec_adapter { + struct module *owner; + char name[32]; + struct cec_devnode devnode; + struct mutex lock; + struct rc_dev *rc; + + struct list_head transmit_queue; + unsigned int transmit_queue_sz; + struct list_head wait_queue; + struct cec_data *transmitting; + bool transmit_in_progress; + bool transmit_in_progress_aborted; + unsigned int xfer_timeout_ms; + + struct task_struct *kthread_config; + struct completion config_completion; + + struct task_struct *kthread; + wait_queue_head_t kthread_waitq; + + const struct cec_adap_ops *ops; + void *priv; + u32 capabilities; + u8 available_log_addrs; + + u16 phys_addr; + bool needs_hpd; + bool is_enabled; + bool is_configuring; + bool must_reconfigure; + bool is_configured; + bool cec_pin_is_high; + bool adap_controls_phys_addr; + u8 last_initiator; + u32 monitor_all_cnt; + u32 monitor_pin_cnt; + u32 follower_cnt; + struct cec_fh *cec_follower; + struct cec_fh *cec_initiator; + bool passthrough; + struct cec_log_addrs log_addrs; + struct cec_connector_info conn_info; + + u32 tx_timeouts; + +#ifdef CONFIG_CEC_NOTIFIER + struct cec_notifier *notifier; +#endif +#ifdef CONFIG_CEC_PIN + struct cec_pin *pin; +#endif + + struct dentry *cec_dir; + + u32 sequence; + + char input_phys[32]; +}; + +static inline void *cec_get_drvdata(const struct cec_adapter *adap) +{ + return adap->priv; +} + +static inline bool cec_has_log_addr(const struct cec_adapter *adap, u8 log_addr) +{ + return adap->log_addrs.log_addr_mask & (1 << log_addr); +} + +static inline bool cec_is_sink(const struct cec_adapter *adap) +{ + return adap->phys_addr == 0; +} + +/** + * cec_is_registered() - is the CEC adapter registered? + * + * @adap: the CEC adapter, may be NULL. + * + * Return: true if the adapter is registered, false otherwise. + */ +static inline bool cec_is_registered(const struct cec_adapter *adap) +{ + return adap && adap->devnode.registered; +} + +#define cec_phys_addr_exp(pa) \ + ((pa) >> 12), ((pa) >> 8) & 0xf, ((pa) >> 4) & 0xf, (pa) & 0xf + +struct edid; +struct drm_connector; + +#if IS_REACHABLE(CONFIG_CEC_CORE) +struct cec_adapter *cec_allocate_adapter(const struct cec_adap_ops *ops, + void *priv, const char *name, u32 caps, u8 available_las); +int cec_register_adapter(struct cec_adapter *adap, struct device *parent); +void cec_unregister_adapter(struct cec_adapter *adap); +void cec_delete_adapter(struct cec_adapter *adap); + +int cec_s_log_addrs(struct cec_adapter *adap, struct cec_log_addrs *log_addrs, + bool block); +void cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, + bool block); +void cec_s_phys_addr_from_edid(struct cec_adapter *adap, + const struct edid *edid); +void cec_s_conn_info(struct cec_adapter *adap, + const struct cec_connector_info *conn_info); +int cec_transmit_msg(struct cec_adapter *adap, struct cec_msg *msg, + bool block); + +/* Called by the adapter */ +void cec_transmit_done_ts(struct cec_adapter *adap, u8 status, + u8 arb_lost_cnt, u8 nack_cnt, u8 low_drive_cnt, + u8 error_cnt, ktime_t ts); + +static inline void cec_transmit_done(struct cec_adapter *adap, u8 status, + u8 arb_lost_cnt, u8 nack_cnt, + u8 low_drive_cnt, u8 error_cnt) +{ + cec_transmit_done_ts(adap, status, arb_lost_cnt, nack_cnt, + low_drive_cnt, error_cnt, ktime_get()); +} +/* + * Simplified version of cec_transmit_done for hardware that doesn't retry + * failed transmits. So this is always just one attempt in which case + * the status is sufficient. + */ +void cec_transmit_attempt_done_ts(struct cec_adapter *adap, + u8 status, ktime_t ts); + +static inline void cec_transmit_attempt_done(struct cec_adapter *adap, + u8 status) +{ + cec_transmit_attempt_done_ts(adap, status, ktime_get()); +} + +void cec_received_msg_ts(struct cec_adapter *adap, + struct cec_msg *msg, ktime_t ts); + +static inline void cec_received_msg(struct cec_adapter *adap, + struct cec_msg *msg) +{ + cec_received_msg_ts(adap, msg, ktime_get()); +} + +/** + * cec_queue_pin_cec_event() - queue a CEC pin event with a given timestamp. + * + * @adap: pointer to the cec adapter + * @is_high: when true the CEC pin is high, otherwise it is low + * @dropped_events: when true some events were dropped + * @ts: the timestamp for this event + * + */ +void cec_queue_pin_cec_event(struct cec_adapter *adap, bool is_high, + bool dropped_events, ktime_t ts); + +/** + * cec_queue_pin_hpd_event() - queue a pin event with a given timestamp. + * + * @adap: pointer to the cec adapter + * @is_high: when true the HPD pin is high, otherwise it is low + * @ts: the timestamp for this event + * + */ +void cec_queue_pin_hpd_event(struct cec_adapter *adap, bool is_high, ktime_t ts); + +/** + * cec_queue_pin_5v_event() - queue a pin event with a given timestamp. + * + * @adap: pointer to the cec adapter + * @is_high: when true the 5V pin is high, otherwise it is low + * @ts: the timestamp for this event + * + */ +void cec_queue_pin_5v_event(struct cec_adapter *adap, bool is_high, ktime_t ts); + +/** + * cec_get_edid_phys_addr() - find and return the physical address + * + * @edid: pointer to the EDID data + * @size: size in bytes of the EDID data + * @offset: If not %NULL then the location of the physical address + * bytes in the EDID will be returned here. This is set to 0 + * if there is no physical address found. + * + * Return: the physical address or CEC_PHYS_ADDR_INVALID if there is none. + */ +u16 cec_get_edid_phys_addr(const u8 *edid, unsigned int size, + unsigned int *offset); + +void cec_fill_conn_info_from_drm(struct cec_connector_info *conn_info, + const struct drm_connector *connector); + +#else + +static inline int cec_register_adapter(struct cec_adapter *adap, + struct device *parent) +{ + return 0; +} + +static inline void cec_unregister_adapter(struct cec_adapter *adap) +{ +} + +static inline void cec_delete_adapter(struct cec_adapter *adap) +{ +} + +static inline void cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, + bool block) +{ +} + +static inline void cec_s_phys_addr_from_edid(struct cec_adapter *adap, + const struct edid *edid) +{ +} + +static inline u16 cec_get_edid_phys_addr(const u8 *edid, unsigned int size, + unsigned int *offset) +{ + if (offset) + *offset = 0; + return CEC_PHYS_ADDR_INVALID; +} + +static inline void cec_s_conn_info(struct cec_adapter *adap, + const struct cec_connector_info *conn_info) +{ +} + +static inline void +cec_fill_conn_info_from_drm(struct cec_connector_info *conn_info, + const struct drm_connector *connector) +{ + memset(conn_info, 0, sizeof(*conn_info)); +} + +#endif + +/** + * cec_phys_addr_invalidate() - set the physical address to INVALID + * + * @adap: the CEC adapter + * + * This is a simple helper function to invalidate the physical + * address. + */ +static inline void cec_phys_addr_invalidate(struct cec_adapter *adap) +{ + cec_s_phys_addr(adap, CEC_PHYS_ADDR_INVALID, false); +} + +/** + * cec_get_edid_spa_location() - find location of the Source Physical Address + * + * @edid: the EDID + * @size: the size of the EDID + * + * This EDID is expected to be a CEA-861 compliant, which means that there are + * at least two blocks and one or more of the extensions blocks are CEA-861 + * blocks. + * + * The returned location is guaranteed to be <= size-2. + * + * This is an inline function since it is used by both CEC and V4L2. + * Ideally this would go in a module shared by both, but it is overkill to do + * that for just a single function. + */ +static inline unsigned int cec_get_edid_spa_location(const u8 *edid, + unsigned int size) +{ + unsigned int blocks = size / 128; + unsigned int block; + u8 d; + + /* Sanity check: at least 2 blocks and a multiple of the block size */ + if (blocks < 2 || size % 128) + return 0; + + /* + * If there are fewer extension blocks than the size, then update + * 'blocks'. It is allowed to have more extension blocks than the size, + * since some hardware can only read e.g. 256 bytes of the EDID, even + * though more blocks are present. The first CEA-861 extension block + * should normally be in block 1 anyway. + */ + if (edid[0x7e] + 1 < blocks) + blocks = edid[0x7e] + 1; + + for (block = 1; block < blocks; block++) { + unsigned int offset = block * 128; + + /* Skip any non-CEA-861 extension blocks */ + if (edid[offset] != 0x02 || edid[offset + 1] != 0x03) + continue; + + /* search Vendor Specific Data Block (tag 3) */ + d = edid[offset + 2] & 0x7f; + /* Check if there are Data Blocks */ + if (d <= 4) + continue; + if (d > 4) { + unsigned int i = offset + 4; + unsigned int end = offset + d; + + /* Note: 'end' is always < 'size' */ + do { + u8 tag = edid[i] >> 5; + u8 len = edid[i] & 0x1f; + + if (tag == 3 && len >= 5 && i + len <= end && + edid[i + 1] == 0x03 && + edid[i + 2] == 0x0c && + edid[i + 3] == 0x00) + return i + 4; + i += len + 1; + } while (i < end); + } + } + return 0; +} + +#endif /* _MEDIA_CEC_H */ |