/* 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/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; u8 match_len; u8 match_reply[5]; 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 2100 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_claiming_log_addrs: true if cec_claim_log_addrs() is running * @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_timeout_cnt: count the number of Timed Out transmits. * Reset to 0 when this is reported in cec_adap_status(). * @tx_low_drive_cnt: count the number of Low Drive transmits. * Reset to 0 when this is reported in cec_adap_status(). * @tx_error_cnt: count the number of Error transmits. * Reset to 0 when this is reported in cec_adap_status(). * @tx_arb_lost_cnt: count the number of Arb Lost transmits. * Reset to 0 when this is reported in cec_adap_status(). * @tx_low_drive_log_cnt: number of logged Low Drive transmits since the * adapter was enabled. Used to avoid flooding the kernel * log if this happens a lot. * @tx_error_log_cnt: number of logged Error transmits since the adapter was * enabled. Used to avoid flooding the kernel log if this * happens a lot. * @notifier: CEC notifier * @pin: CEC pin status struct * @cec_dir: debugfs cec directory * @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_claiming_log_addrs; 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_timeout_cnt; u32 tx_low_drive_cnt; u32 tx_error_cnt; u32 tx_arb_lost_cnt; u32 tx_low_drive_log_cnt; u32 tx_error_log_cnt; #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[40]; }; static inline int cec_get_device(struct cec_adapter *adap) { struct cec_devnode *devnode = &adap->devnode; /* * Check if the cec device is available. This needs to be done with * the devnode->lock held to prevent an open/unregister race: * without the lock, the device could be unregistered and freed between * the devnode->registered check and get_device() calls, leading to * a crash. */ mutex_lock(&devnode->lock); /* * return ENODEV if the cec device has been removed * already or if it is not registered anymore. */ if (!devnode->registered) { mutex_unlock(&devnode->lock); return -ENODEV; } /* and increase the device refcount */ get_device(&devnode->dev); mutex_unlock(&devnode->lock); return 0; } static inline void cec_put_device(struct cec_adapter *adap) { put_device(&adap->devnode.dev); } 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 */
