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Diffstat (limited to 'include/media/cec.h')
| -rw-r--r-- | include/media/cec.h | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/include/media/cec.h b/include/media/cec.h new file mode 100644 index 000000000..fdb5d600e --- /dev/null +++ b/include/media/cec.h @@ -0,0 +1,241 @@ +/* + * cec - HDMI Consumer Electronics Control support header + * + * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + * + * This program is free software; you may redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#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> +#include <media/cec-edid.h> + +/** + * struct cec_devnode - cec device node + * @dev: cec device + * @cdev: cec character device + * @parent: parent 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; + struct device *parent; + + /* device info */ + int minor; + bool registered; + bool unregistered; + struct list_head fhs; + struct mutex lock; +}; + +struct cec_adapter; +struct cec_data; + +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 new_initiator; + bool blocking; + bool completed; +}; + +struct cec_msg_entry { + struct list_head list; + struct cec_msg msg; +}; + +#define CEC_NUM_EVENTS CEC_EVENT_LOST_MSGS + +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; + unsigned int pending_events; + struct cec_event events[CEC_NUM_EVENTS]; + struct mutex lock; + 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_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); + + /* 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 { + 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; + + struct task_struct *kthread_config; + struct completion config_completion; + + struct task_struct *kthread; + wait_queue_head_t kthread_waitq; + wait_queue_head_t waitq; + + const struct cec_adap_ops *ops; + void *priv; + u32 capabilities; + u8 available_log_addrs; + + u16 phys_addr; + bool is_configuring; + bool is_configured; + u32 monitor_all_cnt; + u32 follower_cnt; + struct cec_fh *cec_follower; + struct cec_fh *cec_initiator; + bool passthrough; + struct cec_log_addrs log_addrs; + + struct dentry *cec_dir; + struct dentry *status_file; + + u16 phys_addrs[15]; + u32 sequence; + + char input_name[32]; + char input_phys[32]; + char input_drv[32]; +}; + +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; +} + +#if IS_ENABLED(CONFIG_MEDIA_CEC) +struct cec_adapter *cec_allocate_adapter(const struct cec_adap_ops *ops, + void *priv, const char *name, u32 caps, u8 available_las, + struct device *parent); +int cec_register_adapter(struct cec_adapter *adap); +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); +int cec_transmit_msg(struct cec_adapter *adap, struct cec_msg *msg, + bool block); + +/* Called by the adapter */ +void cec_transmit_done(struct cec_adapter *adap, u8 status, u8 arb_lost_cnt, + u8 nack_cnt, u8 low_drive_cnt, u8 error_cnt); +void cec_received_msg(struct cec_adapter *adap, struct cec_msg *msg); + +#else + +static inline int cec_register_adapter(struct cec_adapter *adap) +{ + 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) +{ +} + +#endif + +#endif /* _MEDIA_CEC_H */ |