diff options
-rw-r--r-- | drivers/staging/media/cec/cec-core.c | 409 | ||||
-rw-r--r-- | drivers/staging/media/cec/cec-priv.h | 56 | ||||
-rw-r--r-- | include/media/cec.h | 232 |
3 files changed, 697 insertions, 0 deletions
diff --git a/drivers/staging/media/cec/cec-core.c b/drivers/staging/media/cec/cec-core.c new file mode 100644 index 0000000..61a1e69 --- /dev/null +++ b/drivers/staging/media/cec/cec-core.c @@ -0,0 +1,409 @@ +/* + * cec-core.c - HDMI Consumer Electronics Control framework - Core + * + * 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. + */ + +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/kmod.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/string.h> +#include <linux/types.h> + +#include "cec-priv.h" + +#define CEC_NUM_DEVICES 256 +#define CEC_NAME "cec" + +int cec_debug; +module_param_named(debug, cec_debug, int, 0644); +MODULE_PARM_DESC(debug, "debug level (0-2)"); + +static dev_t cec_dev_t; + +/* Active devices */ +static DEFINE_MUTEX(cec_devnode_lock); +static DECLARE_BITMAP(cec_devnode_nums, CEC_NUM_DEVICES); + +static struct dentry *top_cec_dir; + +/* dev to cec_devnode */ +#define to_cec_devnode(cd) container_of(cd, struct cec_devnode, dev) + +int cec_get_device(struct cec_devnode *devnode) +{ + /* + * Check if the cec device is available. This needs to be done with + * the cec_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(&cec_devnode_lock); + /* + * return ENXIO if the cec device has been removed + * already or if it is not registered anymore. + */ + if (!devnode->registered) { + mutex_unlock(&cec_devnode_lock); + return -ENXIO; + } + /* and increase the device refcount */ + get_device(&devnode->dev); + mutex_unlock(&cec_devnode_lock); + return 0; +} + +void cec_put_device(struct cec_devnode *devnode) +{ + mutex_lock(&cec_devnode_lock); + put_device(&devnode->dev); + mutex_unlock(&cec_devnode_lock); +} + +/* Called when the last user of the cec device exits. */ +static void cec_devnode_release(struct device *cd) +{ + struct cec_devnode *devnode = to_cec_devnode(cd); + + mutex_lock(&cec_devnode_lock); + + /* Mark device node number as free */ + clear_bit(devnode->minor, cec_devnode_nums); + + mutex_unlock(&cec_devnode_lock); + cec_delete_adapter(to_cec_adapter(devnode)); +} + +static struct bus_type cec_bus_type = { + .name = CEC_NAME, +}; + +/* + * Register a cec device node + * + * The registration code assigns minor numbers and registers the new device node + * with the kernel. An error is returned if no free minor number can be found, + * or if the registration of the device node fails. + * + * Zero is returned on success. + * + * Note that if the cec_devnode_register call fails, the release() callback of + * the cec_devnode structure is *not* called, so the caller is responsible for + * freeing any data. + */ +static int __must_check cec_devnode_register(struct cec_devnode *devnode, + struct module *owner) +{ + int minor; + int ret; + + /* Initialization */ + INIT_LIST_HEAD(&devnode->fhs); + mutex_init(&devnode->fhs_lock); + + /* Part 1: Find a free minor number */ + mutex_lock(&cec_devnode_lock); + minor = find_next_zero_bit(cec_devnode_nums, CEC_NUM_DEVICES, 0); + if (minor == CEC_NUM_DEVICES) { + mutex_unlock(&cec_devnode_lock); + pr_err("could not get a free minor\n"); + return -ENFILE; + } + + set_bit(minor, cec_devnode_nums); + mutex_unlock(&cec_devnode_lock); + + devnode->minor = minor; + devnode->dev.bus = &cec_bus_type; + devnode->dev.devt = MKDEV(MAJOR(cec_dev_t), minor); + devnode->dev.release = cec_devnode_release; + devnode->dev.parent = devnode->parent; + dev_set_name(&devnode->dev, "cec%d", devnode->minor); + device_initialize(&devnode->dev); + + /* Part 2: Initialize and register the character device */ + cdev_init(&devnode->cdev, &cec_devnode_fops); + devnode->cdev.kobj.parent = &devnode->dev.kobj; + devnode->cdev.owner = owner; + + ret = cdev_add(&devnode->cdev, devnode->dev.devt, 1); + if (ret < 0) { + pr_err("%s: cdev_add failed\n", __func__); + goto clr_bit; + } + + ret = device_add(&devnode->dev); + if (ret) + goto cdev_del; + + devnode->registered = true; + return 0; + +cdev_del: + cdev_del(&devnode->cdev); +clr_bit: + clear_bit(devnode->minor, cec_devnode_nums); + return ret; +} + +/* + * Unregister a cec device node + * + * This unregisters the passed device. Future open calls will be met with + * errors. + * + * This function can safely be called if the device node has never been + * registered or has already been unregistered. + */ +static void cec_devnode_unregister(struct cec_devnode *devnode) +{ + struct cec_fh *fh; + + /* Check if devnode was never registered or already unregistered */ + if (!devnode->registered || devnode->unregistered) + return; + + mutex_lock(&devnode->fhs_lock); + list_for_each_entry(fh, &devnode->fhs, list) + wake_up_interruptible(&fh->wait); + mutex_unlock(&devnode->fhs_lock); + + devnode->registered = false; + devnode->unregistered = true; + device_del(&devnode->dev); + cdev_del(&devnode->cdev); + put_device(&devnode->dev); +} + +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) +{ + struct cec_adapter *adap; + int res; + + if (WARN_ON(!parent)) + return ERR_PTR(-EINVAL); + if (WARN_ON(!caps)) + return ERR_PTR(-EINVAL); + if (WARN_ON(!ops)) + return ERR_PTR(-EINVAL); + if (WARN_ON(!available_las || available_las > CEC_MAX_LOG_ADDRS)) + return ERR_PTR(-EINVAL); + adap = kzalloc(sizeof(*adap), GFP_KERNEL); + if (!adap) + return ERR_PTR(-ENOMEM); + adap->owner = parent->driver->owner; + adap->devnode.parent = parent; + strlcpy(adap->name, name, sizeof(adap->name)); + adap->phys_addr = CEC_PHYS_ADDR_INVALID; + adap->log_addrs.cec_version = CEC_OP_CEC_VERSION_2_0; + adap->log_addrs.vendor_id = CEC_VENDOR_ID_NONE; + adap->capabilities = caps; + adap->available_log_addrs = available_las; + adap->sequence = 0; + adap->ops = ops; + adap->priv = priv; + memset(adap->phys_addrs, 0xff, sizeof(adap->phys_addrs)); + mutex_init(&adap->lock); + INIT_LIST_HEAD(&adap->transmit_queue); + INIT_LIST_HEAD(&adap->wait_queue); + init_waitqueue_head(&adap->kthread_waitq); + + adap->kthread = kthread_run(cec_thread_func, adap, "cec-%s", name); + if (IS_ERR(adap->kthread)) { + pr_err("cec-%s: kernel_thread() failed\n", name); + res = PTR_ERR(adap->kthread); + kfree(adap); + return ERR_PTR(res); + } + + if (!(caps & CEC_CAP_RC)) + return adap; + +#if IS_ENABLED(CONFIG_RC_CORE) + /* Prepare the RC input device */ + adap->rc = rc_allocate_device(); + if (!adap->rc) { + pr_err("cec-%s: failed to allocate memory for rc_dev\n", + name); + kthread_stop(adap->kthread); + kfree(adap); + return ERR_PTR(-ENOMEM); + } + + snprintf(adap->input_name, sizeof(adap->input_name), + "RC for %s", name); + snprintf(adap->input_phys, sizeof(adap->input_phys), + "%s/input0", name); + + adap->rc->input_name = adap->input_name; + adap->rc->input_phys = adap->input_phys; + adap->rc->input_id.bustype = BUS_CEC; + adap->rc->input_id.vendor = 0; + adap->rc->input_id.product = 0; + adap->rc->input_id.version = 1; + adap->rc->dev.parent = parent; + adap->rc->driver_type = RC_DRIVER_SCANCODE; + adap->rc->driver_name = CEC_NAME; + adap->rc->allowed_protocols = RC_BIT_CEC; + adap->rc->priv = adap; + adap->rc->map_name = RC_MAP_CEC; + adap->rc->timeout = MS_TO_NS(100); +#else + adap->capabilities &= ~CEC_CAP_RC; +#endif + return adap; +} +EXPORT_SYMBOL_GPL(cec_allocate_adapter); + +int cec_register_adapter(struct cec_adapter *adap) +{ + int res; + + if (IS_ERR_OR_NULL(adap)) + return 0; + +#if IS_ENABLED(CONFIG_RC_CORE) + if (adap->capabilities & CEC_CAP_RC) { + res = rc_register_device(adap->rc); + + if (res) { + pr_err("cec-%s: failed to prepare input device\n", + adap->name); + rc_free_device(adap->rc); + adap->rc = NULL; + return res; + } + } +#endif + + res = cec_devnode_register(&adap->devnode, adap->owner); + if (res) { +#if IS_ENABLED(CONFIG_RC_CORE) + /* Note: rc_unregister also calls rc_free */ + rc_unregister_device(adap->rc); + adap->rc = NULL; +#endif + return res; + } + + dev_set_drvdata(&adap->devnode.dev, adap); +#ifdef CONFIG_MEDIA_CEC_DEBUG + if (!top_cec_dir) + return 0; + + adap->cec_dir = debugfs_create_dir(dev_name(&adap->devnode.dev), top_cec_dir); + if (IS_ERR_OR_NULL(adap->cec_dir)) { + pr_warn("cec-%s: Failed to create debugfs dir\n", adap->name); + return 0; + } + adap->status_file = debugfs_create_devm_seqfile(&adap->devnode.dev, + "status", adap->cec_dir, cec_adap_status); + if (IS_ERR_OR_NULL(adap->status_file)) { + pr_warn("cec-%s: Failed to create status file\n", adap->name); + debugfs_remove_recursive(adap->cec_dir); + adap->cec_dir = NULL; + } +#endif + return 0; +} +EXPORT_SYMBOL_GPL(cec_register_adapter); + +void cec_unregister_adapter(struct cec_adapter *adap) +{ + if (IS_ERR_OR_NULL(adap)) + return; + +#if IS_ENABLED(CONFIG_RC_CORE) + /* Note: rc_unregister also calls rc_free */ + rc_unregister_device(adap->rc); + adap->rc = NULL; +#endif + debugfs_remove_recursive(adap->cec_dir); + cec_devnode_unregister(&adap->devnode); +} +EXPORT_SYMBOL_GPL(cec_unregister_adapter); + +void cec_delete_adapter(struct cec_adapter *adap) +{ + if (IS_ERR_OR_NULL(adap)) + return; + mutex_lock(&adap->lock); + __cec_s_phys_addr(adap, CEC_PHYS_ADDR_INVALID, false); + mutex_unlock(&adap->lock); + kthread_stop(adap->kthread); + if (adap->kthread_config) + kthread_stop(adap->kthread_config); +#if IS_ENABLED(CONFIG_RC_CORE) + if (adap->rc) + rc_free_device(adap->rc); +#endif + kfree(adap); +} +EXPORT_SYMBOL_GPL(cec_delete_adapter); + +/* + * Initialise cec for linux + */ +static int __init cec_devnode_init(void) +{ + int ret; + + pr_info("Linux cec interface: v0.10\n"); + ret = alloc_chrdev_region(&cec_dev_t, 0, CEC_NUM_DEVICES, + CEC_NAME); + if (ret < 0) { + pr_warn("cec: unable to allocate major\n"); + return ret; + } + +#ifdef CONFIG_MEDIA_CEC_DEBUG + top_cec_dir = debugfs_create_dir("cec", NULL); + if (IS_ERR_OR_NULL(top_cec_dir)) { + pr_warn("cec: Failed to create debugfs cec dir\n"); + top_cec_dir = NULL; + } +#endif + + ret = bus_register(&cec_bus_type); + if (ret < 0) { + unregister_chrdev_region(cec_dev_t, CEC_NUM_DEVICES); + pr_warn("cec: bus_register failed\n"); + return -EIO; + } + + return 0; +} + +static void __exit cec_devnode_exit(void) +{ + debugfs_remove_recursive(top_cec_dir); + bus_unregister(&cec_bus_type); + unregister_chrdev_region(cec_dev_t, CEC_NUM_DEVICES); +} + +subsys_initcall(cec_devnode_init); +module_exit(cec_devnode_exit) + +MODULE_AUTHOR("Hans Verkuil <hans.verkuil@cisco.com>"); +MODULE_DESCRIPTION("Device node registration for cec drivers"); +MODULE_LICENSE("GPL"); diff --git a/drivers/staging/media/cec/cec-priv.h b/drivers/staging/media/cec/cec-priv.h new file mode 100644 index 0000000..70767a7 --- /dev/null +++ b/drivers/staging/media/cec/cec-priv.h @@ -0,0 +1,56 @@ +/* + * cec-priv.h - HDMI Consumer Electronics Control internal 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 _CEC_PRIV_H +#define _CEC_PRIV_H + +#include <linux/cec-funcs.h> +#include <media/cec.h> + +#define dprintk(lvl, fmt, arg...) \ + do { \ + if (lvl <= cec_debug) \ + pr_info("cec-%s: " fmt, adap->name, ## arg); \ + } while (0) + +/* devnode to cec_adapter */ +#define to_cec_adapter(node) container_of(node, struct cec_adapter, devnode) + +/* cec-core.c */ +extern int cec_debug; +int cec_get_device(struct cec_devnode *devnode); +void cec_put_device(struct cec_devnode *devnode); + +/* cec-adap.c */ +int cec_monitor_all_cnt_inc(struct cec_adapter *adap); +void cec_monitor_all_cnt_dec(struct cec_adapter *adap); +int cec_adap_status(struct seq_file *file, void *priv); +int cec_thread_func(void *_adap); +void __cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, bool block); +int __cec_s_log_addrs(struct cec_adapter *adap, + struct cec_log_addrs *log_addrs, bool block); +int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg, + struct cec_fh *fh, bool block); +void cec_queue_event_fh(struct cec_fh *fh, + const struct cec_event *new_ev, u64 ts); + +/* cec-api.c */ +extern const struct file_operations cec_devnode_fops; + +#endif diff --git a/include/media/cec.h b/include/media/cec.h new file mode 100644 index 0000000..9a791c0 --- /dev/null +++ b/include/media/cec.h @@ -0,0 +1,232 @@ +/* + * 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 mutex fhs_lock; + struct list_head fhs; +}; + +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 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_QUEUE_SZ (18 * 3) + +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; + 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 */ |