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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /include/media/cec.h
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
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Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/media/cec.h')
-rw-r--r--include/media/cec.h523
1 files changed, 523 insertions, 0 deletions
diff --git a/include/media/cec.h b/include/media/cec.h
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+/* 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
+ * @registered: the device was correctly registered
+ * @unregistered: the device was unregistered
+ * @fhs_lock: lock to control access to the filehandle list
+ * @fhs: the list of open filehandles (cec_fh)
+ *
+ * This structure represents a cec-related device node.
+ *
+ * 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;
+ bool registered;
+ bool unregistered;
+ struct list_head fhs;
+ struct mutex lock;
+};
+
+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 */
+ 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);
+ int (*adap_transmit)(struct cec_adapter *adap, u8 attempts,
+ u32 signal_free_time, 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 */
+ 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 */
+ 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
+ * @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_configuring: the CEC adapter is configuring (i.e. claiming 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;
+
+ 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_configuring;
+ 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 */