1 /* 2 * cec - HDMI Consumer Electronics Control support header 3 * 4 * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 5 * 6 * This program is free software; you may redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; version 2 of the License. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 11 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 12 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 13 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 14 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 15 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 16 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 17 * SOFTWARE. 18 */ 19 20 #ifndef _MEDIA_CEC_H 21 #define _MEDIA_CEC_H 22 23 #include <linux/poll.h> 24 #include <linux/fs.h> 25 #include <linux/debugfs.h> 26 #include <linux/device.h> 27 #include <linux/cdev.h> 28 #include <linux/kthread.h> 29 #include <linux/timer.h> 30 #include <linux/cec-funcs.h> 31 #include <media/rc-core.h> 32 #include <media/cec-edid.h> 33 34 /** 35 * struct cec_devnode - cec device node 36 * @dev: cec device 37 * @cdev: cec character device 38 * @parent: parent device 39 * @minor: device node minor number 40 * @registered: the device was correctly registered 41 * @unregistered: the device was unregistered 42 * @fhs_lock: lock to control access to the filehandle list 43 * @fhs: the list of open filehandles (cec_fh) 44 * 45 * This structure represents a cec-related device node. 46 * 47 * The @parent is a physical device. It must be set by core or device drivers 48 * before registering the node. 49 */ 50 struct cec_devnode { 51 /* sysfs */ 52 struct device dev; 53 struct cdev cdev; 54 struct device *parent; 55 56 /* device info */ 57 int minor; 58 bool registered; 59 bool unregistered; 60 struct mutex fhs_lock; 61 struct list_head fhs; 62 }; 63 64 struct cec_adapter; 65 struct cec_data; 66 67 struct cec_data { 68 struct list_head list; 69 struct list_head xfer_list; 70 struct cec_adapter *adap; 71 struct cec_msg msg; 72 struct cec_fh *fh; 73 struct delayed_work work; 74 struct completion c; 75 u8 attempts; 76 bool new_initiator; 77 bool blocking; 78 bool completed; 79 }; 80 81 struct cec_msg_entry { 82 struct list_head list; 83 struct cec_msg msg; 84 }; 85 86 #define CEC_NUM_EVENTS CEC_EVENT_LOST_MSGS 87 88 struct cec_fh { 89 struct list_head list; 90 struct list_head xfer_list; 91 struct cec_adapter *adap; 92 u8 mode_initiator; 93 u8 mode_follower; 94 95 /* Events */ 96 wait_queue_head_t wait; 97 unsigned int pending_events; 98 struct cec_event events[CEC_NUM_EVENTS]; 99 struct mutex lock; 100 struct list_head msgs; /* queued messages */ 101 unsigned int queued_msgs; 102 }; 103 104 #define CEC_SIGNAL_FREE_TIME_RETRY 3 105 #define CEC_SIGNAL_FREE_TIME_NEW_INITIATOR 5 106 #define CEC_SIGNAL_FREE_TIME_NEXT_XFER 7 107 108 /* The nominal data bit period is 2.4 ms */ 109 #define CEC_FREE_TIME_TO_USEC(ft) ((ft) * 2400) 110 111 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_log_addr)(struct cec_adapter *adap, u8 logical_addr); 116 int (*adap_transmit)(struct cec_adapter *adap, u8 attempts, 117 u32 signal_free_time, struct cec_msg *msg); 118 void (*adap_status)(struct cec_adapter *adap, struct seq_file *file); 119 120 /* High-level CEC message callback */ 121 int (*received)(struct cec_adapter *adap, struct cec_msg *msg); 122 }; 123 124 /* 125 * The minimum message length you can receive (excepting poll messages) is 2. 126 * With a transfer rate of at most 36 bytes per second this makes 18 messages 127 * per second worst case. 128 * 129 * We queue at most 3 seconds worth of messages. The CEC specification requires 130 * that messages are replied to within a second, so 3 seconds should give more 131 * than enough margin. Since most messages are actually more than 2 bytes, this 132 * is in practice a lot more than 3 seconds. 133 */ 134 #define CEC_MAX_MSG_QUEUE_SZ (18 * 3) 135 136 struct cec_adapter { 137 struct module *owner; 138 char name[32]; 139 struct cec_devnode devnode; 140 struct mutex lock; 141 struct rc_dev *rc; 142 143 struct list_head transmit_queue; 144 struct list_head wait_queue; 145 struct cec_data *transmitting; 146 147 struct task_struct *kthread_config; 148 struct completion config_completion; 149 150 struct task_struct *kthread; 151 wait_queue_head_t kthread_waitq; 152 wait_queue_head_t waitq; 153 154 const struct cec_adap_ops *ops; 155 void *priv; 156 u32 capabilities; 157 u8 available_log_addrs; 158 159 u16 phys_addr; 160 bool is_configuring; 161 bool is_configured; 162 u32 monitor_all_cnt; 163 u32 follower_cnt; 164 struct cec_fh *cec_follower; 165 struct cec_fh *cec_initiator; 166 bool passthrough; 167 struct cec_log_addrs log_addrs; 168 169 struct dentry *cec_dir; 170 struct dentry *status_file; 171 172 u16 phys_addrs[15]; 173 u32 sequence; 174 175 char input_name[32]; 176 char input_phys[32]; 177 char input_drv[32]; 178 }; 179 180 static inline bool cec_has_log_addr(const struct cec_adapter *adap, u8 log_addr) 181 { 182 return adap->log_addrs.log_addr_mask & (1 << log_addr); 183 } 184 185 static inline bool cec_is_sink(const struct cec_adapter *adap) 186 { 187 return adap->phys_addr == 0; 188 } 189 190 #if IS_ENABLED(CONFIG_MEDIA_CEC) 191 struct cec_adapter *cec_allocate_adapter(const struct cec_adap_ops *ops, 192 void *priv, const char *name, u32 caps, u8 available_las, 193 struct device *parent); 194 int cec_register_adapter(struct cec_adapter *adap); 195 void cec_unregister_adapter(struct cec_adapter *adap); 196 void cec_delete_adapter(struct cec_adapter *adap); 197 198 int cec_s_log_addrs(struct cec_adapter *adap, struct cec_log_addrs *log_addrs, 199 bool block); 200 void cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, 201 bool block); 202 int cec_transmit_msg(struct cec_adapter *adap, struct cec_msg *msg, 203 bool block); 204 205 /* Called by the adapter */ 206 void cec_transmit_done(struct cec_adapter *adap, u8 status, u8 arb_lost_cnt, 207 u8 nack_cnt, u8 low_drive_cnt, u8 error_cnt); 208 void cec_received_msg(struct cec_adapter *adap, struct cec_msg *msg); 209 210 #else 211 212 static inline int cec_register_adapter(struct cec_adapter *adap) 213 { 214 return 0; 215 } 216 217 static inline void cec_unregister_adapter(struct cec_adapter *adap) 218 { 219 } 220 221 static inline void cec_delete_adapter(struct cec_adapter *adap) 222 { 223 } 224 225 static inline void cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, 226 bool block) 227 { 228 } 229 230 #endif 231 232 #endif /* _MEDIA_CEC_H */ 233