From ca684386e6e21ba1511061f71577cdb6c3f2b3d3 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 25 Jun 2016 09:44:43 -0300 Subject: [PATCH] [media] cec: add HDMI CEC framework (api) The added HDMI CEC framework provides a generic kernel interface for HDMI CEC devices. Note that the CEC framework is added to staging/media and that the cec.h and cec-funcs.h headers are not exported yet. While the kABI is mature, I would prefer to allow the uABI some more time before it is mainlined in case it needs more tweaks. This adds the cec-api.c source that deals with the public CEC API and the Kconfig/Makefile plumbing. The MAINTAINERS file is also updated. Signed-off-by: Hans Verkuil [k.debski@samsung.com: code cleanup and fixes] Signed-off-by: Kamil Debski Signed-off-by: Mauro Carvalho Chehab --- MAINTAINERS | 16 + drivers/staging/media/Kconfig | 2 + drivers/staging/media/Makefile | 1 + drivers/staging/media/cec/Kconfig | 14 + drivers/staging/media/cec/Makefile | 3 + drivers/staging/media/cec/cec-api.c | 578 ++++++++++++++++++++++++++++ 6 files changed, 614 insertions(+) create mode 100644 drivers/staging/media/cec/Kconfig create mode 100644 drivers/staging/media/cec/Makefile create mode 100644 drivers/staging/media/cec/cec-api.c diff --git a/MAINTAINERS b/MAINTAINERS index 02299fd2db18..848d37dafd90 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2847,6 +2847,22 @@ F: drivers/net/ieee802154/cc2520.c F: include/linux/spi/cc2520.h F: Documentation/devicetree/bindings/net/ieee802154/cc2520.txt +CEC DRIVER +M: Hans Verkuil +L: linux-media@vger.kernel.org +T: git git://linuxtv.org/media_tree.git +W: http://linuxtv.org +S: Supported +F: Documentation/cec.txt +F: Documentation/DocBook/media/v4l/cec* +F: drivers/staging/media/cec/ +F: drivers/media/cec-edid.c +F: drivers/media/rc/keymaps/rc-cec.c +F: include/media/cec.h +F: include/media/cec-edid.h +F: include/linux/cec.h +F: include/linux/cec-funcs.h + CELL BROADBAND ENGINE ARCHITECTURE M: Arnd Bergmann L: linuxppc-dev@lists.ozlabs.org diff --git a/drivers/staging/media/Kconfig b/drivers/staging/media/Kconfig index ee9186843371..7ce679eb87e1 100644 --- a/drivers/staging/media/Kconfig +++ b/drivers/staging/media/Kconfig @@ -21,6 +21,8 @@ if STAGING_MEDIA # Please keep them in alphabetic order source "drivers/staging/media/bcm2048/Kconfig" +source "drivers/staging/media/cec/Kconfig" + source "drivers/staging/media/cxd2099/Kconfig" source "drivers/staging/media/davinci_vpfe/Kconfig" diff --git a/drivers/staging/media/Makefile b/drivers/staging/media/Makefile index 8c05d0ace0fb..2d213dd54bc3 100644 --- a/drivers/staging/media/Makefile +++ b/drivers/staging/media/Makefile @@ -1,4 +1,5 @@ obj-$(CONFIG_I2C_BCM2048) += bcm2048/ +obj-$(CONFIG_MEDIA_CEC) += cec/ obj-$(CONFIG_DVB_CXD2099) += cxd2099/ obj-$(CONFIG_LIRC_STAGING) += lirc/ obj-$(CONFIG_VIDEO_DM365_VPFE) += davinci_vpfe/ diff --git a/drivers/staging/media/cec/Kconfig b/drivers/staging/media/cec/Kconfig new file mode 100644 index 000000000000..8a7aceeac815 --- /dev/null +++ b/drivers/staging/media/cec/Kconfig @@ -0,0 +1,14 @@ +config MEDIA_CEC + tristate "CEC API (EXPERIMENTAL)" + select MEDIA_CEC_EDID + ---help--- + Enable the CEC API. + + To compile this driver as a module, choose M here: the + module will be called cec. + +config MEDIA_CEC_DEBUG + bool "CEC debugfs interface (EXPERIMENTAL)" + depends on MEDIA_CEC && DEBUG_FS + ---help--- + Turns on the DebugFS interface for CEC devices. diff --git a/drivers/staging/media/cec/Makefile b/drivers/staging/media/cec/Makefile new file mode 100644 index 000000000000..426ef73b959f --- /dev/null +++ b/drivers/staging/media/cec/Makefile @@ -0,0 +1,3 @@ +cec-objs := cec-core.o cec-adap.o cec-api.o + +obj-$(CONFIG_MEDIA_CEC) += cec.o diff --git a/drivers/staging/media/cec/cec-api.c b/drivers/staging/media/cec/cec-api.c new file mode 100644 index 000000000000..d7cba7a7d6b0 --- /dev/null +++ b/drivers/staging/media/cec/cec-api.c @@ -0,0 +1,578 @@ +/* + * cec-api.c - HDMI Consumer Electronics Control framework - API + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "cec-priv.h" + +static inline struct cec_devnode *cec_devnode_data(struct file *filp) +{ + struct cec_fh *fh = filp->private_data; + + return &fh->adap->devnode; +} + +/* CEC file operations */ + +static unsigned int cec_poll(struct file *filp, + struct poll_table_struct *poll) +{ + struct cec_devnode *devnode = cec_devnode_data(filp); + struct cec_fh *fh = filp->private_data; + struct cec_adapter *adap = fh->adap; + unsigned int res = 0; + + if (!devnode->registered) + return POLLERR | POLLHUP; + mutex_lock(&adap->lock); + if (adap->is_configured) + res |= POLLOUT | POLLWRNORM; + if (fh->queued_msgs) + res |= POLLIN | POLLRDNORM; + if (fh->pending_events) + res |= POLLPRI; + poll_wait(filp, &fh->wait, poll); + mutex_unlock(&adap->lock); + return res; +} + +static bool cec_is_busy(const struct cec_adapter *adap, + const struct cec_fh *fh) +{ + bool valid_initiator = adap->cec_initiator && adap->cec_initiator == fh; + bool valid_follower = adap->cec_follower && adap->cec_follower == fh; + + /* + * Exclusive initiators and followers can always access the CEC adapter + */ + if (valid_initiator || valid_follower) + return false; + /* + * All others can only access the CEC adapter if there is no + * exclusive initiator and they are in INITIATOR mode. + */ + return adap->cec_initiator || + fh->mode_initiator == CEC_MODE_NO_INITIATOR; +} + +static long cec_adap_g_caps(struct cec_adapter *adap, + struct cec_caps __user *parg) +{ + struct cec_caps caps = {}; + + strlcpy(caps.driver, adap->devnode.parent->driver->name, + sizeof(caps.driver)); + strlcpy(caps.name, adap->name, sizeof(caps.name)); + caps.available_log_addrs = adap->available_log_addrs; + caps.capabilities = adap->capabilities; + caps.version = LINUX_VERSION_CODE; + if (copy_to_user(parg, &caps, sizeof(caps))) + return -EFAULT; + return 0; +} + +static long cec_adap_g_phys_addr(struct cec_adapter *adap, + __u16 __user *parg) +{ + u16 phys_addr; + + mutex_lock(&adap->lock); + phys_addr = adap->phys_addr; + mutex_unlock(&adap->lock); + if (copy_to_user(parg, &phys_addr, sizeof(phys_addr))) + return -EFAULT; + return 0; +} + +static long cec_adap_s_phys_addr(struct cec_adapter *adap, struct cec_fh *fh, + bool block, __u16 __user *parg) +{ + u16 phys_addr; + long err; + + if (!(adap->capabilities & CEC_CAP_PHYS_ADDR)) + return -ENOTTY; + if (copy_from_user(&phys_addr, parg, sizeof(phys_addr))) + return -EFAULT; + + err = cec_phys_addr_validate(phys_addr, NULL, NULL); + if (err) + return err; + mutex_lock(&adap->lock); + if (cec_is_busy(adap, fh)) + err = -EBUSY; + else + __cec_s_phys_addr(adap, phys_addr, block); + mutex_unlock(&adap->lock); + return err; +} + +static long cec_adap_g_log_addrs(struct cec_adapter *adap, + struct cec_log_addrs __user *parg) +{ + struct cec_log_addrs log_addrs; + + mutex_lock(&adap->lock); + log_addrs = adap->log_addrs; + if (!adap->is_configured) + memset(log_addrs.log_addr, CEC_LOG_ADDR_INVALID, + sizeof(log_addrs.log_addr)); + mutex_unlock(&adap->lock); + + if (copy_to_user(parg, &log_addrs, sizeof(log_addrs))) + return -EFAULT; + return 0; +} + +static long cec_adap_s_log_addrs(struct cec_adapter *adap, struct cec_fh *fh, + bool block, struct cec_log_addrs __user *parg) +{ + struct cec_log_addrs log_addrs; + long err = -EBUSY; + + if (!(adap->capabilities & CEC_CAP_LOG_ADDRS)) + return -ENOTTY; + if (copy_from_user(&log_addrs, parg, sizeof(log_addrs))) + return -EFAULT; + log_addrs.flags = 0; + mutex_lock(&adap->lock); + if (!adap->is_configuring && + (!log_addrs.num_log_addrs || !adap->is_configured) && + !cec_is_busy(adap, fh)) { + err = __cec_s_log_addrs(adap, &log_addrs, block); + if (!err) + log_addrs = adap->log_addrs; + } + mutex_unlock(&adap->lock); + if (err) + return err; + if (copy_to_user(parg, &log_addrs, sizeof(log_addrs))) + return -EFAULT; + return 0; +} + +static long cec_transmit(struct cec_adapter *adap, struct cec_fh *fh, + bool block, struct cec_msg __user *parg) +{ + struct cec_msg msg = {}; + long err = 0; + + if (!(adap->capabilities & CEC_CAP_TRANSMIT)) + return -ENOTTY; + if (copy_from_user(&msg, parg, sizeof(msg))) + return -EFAULT; + mutex_lock(&adap->lock); + if (!adap->is_configured) { + err = -ENONET; + } else if (cec_is_busy(adap, fh)) { + err = -EBUSY; + } else { + if (!block || !msg.reply) + fh = NULL; + err = cec_transmit_msg_fh(adap, &msg, fh, block); + } + mutex_unlock(&adap->lock); + if (err) + return err; + if (copy_to_user(parg, &msg, sizeof(msg))) + return -EFAULT; + return 0; +} + +/* Called by CEC_RECEIVE: wait for a message to arrive */ +static int cec_receive_msg(struct cec_fh *fh, struct cec_msg *msg, bool block) +{ + int res; + + do { + mutex_lock(&fh->lock); + /* Are there received messages queued up? */ + if (fh->queued_msgs) { + /* Yes, return the first one */ + struct cec_msg_entry *entry = + list_first_entry(&fh->msgs, + struct cec_msg_entry, list); + + list_del(&entry->list); + *msg = entry->msg; + kfree(entry); + fh->queued_msgs--; + mutex_unlock(&fh->lock); + return 0; + } + + /* No, return EAGAIN in non-blocking mode or wait */ + mutex_unlock(&fh->lock); + + /* Return when in non-blocking mode */ + if (!block) + return -EAGAIN; + + if (msg->timeout) { + /* The user specified a timeout */ + res = wait_event_interruptible_timeout(fh->wait, + fh->queued_msgs, + msecs_to_jiffies(msg->timeout)); + if (res == 0) + res = -ETIMEDOUT; + else if (res > 0) + res = 0; + } else { + /* Wait indefinitely */ + res = wait_event_interruptible(fh->wait, + fh->queued_msgs); + } + /* Exit on error, otherwise loop to get the new message */ + } while (!res); + return res; +} + +static long cec_receive(struct cec_adapter *adap, struct cec_fh *fh, + bool block, struct cec_msg __user *parg) +{ + struct cec_msg msg = {}; + long err = 0; + + if (copy_from_user(&msg, parg, sizeof(msg))) + return -EFAULT; + mutex_lock(&adap->lock); + if (!adap->is_configured) + err = -ENONET; + mutex_unlock(&adap->lock); + if (err) + return err; + + err = cec_receive_msg(fh, &msg, block); + if (err) + return err; + if (copy_to_user(parg, &msg, sizeof(msg))) + return -EFAULT; + return 0; +} + +static long cec_dqevent(struct cec_adapter *adap, struct cec_fh *fh, + bool block, struct cec_event __user *parg) +{ + struct cec_event *ev = NULL; + u64 ts = ~0ULL; + unsigned int i; + long err = 0; + + mutex_lock(&fh->lock); + while (!fh->pending_events && block) { + mutex_unlock(&fh->lock); + err = wait_event_interruptible(fh->wait, fh->pending_events); + if (err) + return err; + mutex_lock(&fh->lock); + } + + /* Find the oldest event */ + for (i = 0; i < CEC_NUM_EVENTS; i++) { + if (fh->pending_events & (1 << (i + 1)) && + fh->events[i].ts <= ts) { + ev = &fh->events[i]; + ts = ev->ts; + } + } + if (!ev) { + err = -EAGAIN; + goto unlock; + } + + if (copy_to_user(parg, ev, sizeof(*ev))) { + err = -EFAULT; + goto unlock; + } + + fh->pending_events &= ~(1 << ev->event); + +unlock: + mutex_unlock(&fh->lock); + return err; +} + +static long cec_g_mode(struct cec_adapter *adap, struct cec_fh *fh, + u32 __user *parg) +{ + u32 mode = fh->mode_initiator | fh->mode_follower; + + if (copy_to_user(parg, &mode, sizeof(mode))) + return -EFAULT; + return 0; +} + +static long cec_s_mode(struct cec_adapter *adap, struct cec_fh *fh, + u32 __user *parg) +{ + u32 mode; + u8 mode_initiator; + u8 mode_follower; + long err = 0; + + if (copy_from_user(&mode, parg, sizeof(mode))) + return -EFAULT; + if (mode & ~(CEC_MODE_INITIATOR_MSK | CEC_MODE_FOLLOWER_MSK)) + return -EINVAL; + + mode_initiator = mode & CEC_MODE_INITIATOR_MSK; + mode_follower = mode & CEC_MODE_FOLLOWER_MSK; + + if (mode_initiator > CEC_MODE_EXCL_INITIATOR || + mode_follower > CEC_MODE_MONITOR_ALL) + return -EINVAL; + + if (mode_follower == CEC_MODE_MONITOR_ALL && + !(adap->capabilities & CEC_CAP_MONITOR_ALL)) + return -EINVAL; + + /* Follower modes should always be able to send CEC messages */ + if ((mode_initiator == CEC_MODE_NO_INITIATOR || + !(adap->capabilities & CEC_CAP_TRANSMIT)) && + mode_follower >= CEC_MODE_FOLLOWER && + mode_follower <= CEC_MODE_EXCL_FOLLOWER_PASSTHRU) + return -EINVAL; + + /* Monitor modes require CEC_MODE_NO_INITIATOR */ + if (mode_initiator && mode_follower >= CEC_MODE_MONITOR) + return -EINVAL; + + /* Monitor modes require CAP_NET_ADMIN */ + if (mode_follower >= CEC_MODE_MONITOR && !capable(CAP_NET_ADMIN)) + return -EPERM; + + mutex_lock(&adap->lock); + /* + * You can't become exclusive follower if someone else already + * has that job. + */ + if ((mode_follower == CEC_MODE_EXCL_FOLLOWER || + mode_follower == CEC_MODE_EXCL_FOLLOWER_PASSTHRU) && + adap->cec_follower && adap->cec_follower != fh) + err = -EBUSY; + /* + * You can't become exclusive initiator if someone else already + * has that job. + */ + if (mode_initiator == CEC_MODE_EXCL_INITIATOR && + adap->cec_initiator && adap->cec_initiator != fh) + err = -EBUSY; + + if (!err) { + bool old_mon_all = fh->mode_follower == CEC_MODE_MONITOR_ALL; + bool new_mon_all = mode_follower == CEC_MODE_MONITOR_ALL; + + if (old_mon_all != new_mon_all) { + if (new_mon_all) + err = cec_monitor_all_cnt_inc(adap); + else + cec_monitor_all_cnt_dec(adap); + } + } + + if (err) { + mutex_unlock(&adap->lock); + return err; + } + + if (fh->mode_follower == CEC_MODE_FOLLOWER) + adap->follower_cnt--; + if (mode_follower == CEC_MODE_FOLLOWER) + adap->follower_cnt++; + if (mode_follower == CEC_MODE_EXCL_FOLLOWER || + mode_follower == CEC_MODE_EXCL_FOLLOWER_PASSTHRU) { + adap->passthrough = + mode_follower == CEC_MODE_EXCL_FOLLOWER_PASSTHRU; + adap->cec_follower = fh; + } else if (adap->cec_follower == fh) { + adap->passthrough = false; + adap->cec_follower = NULL; + } + if (mode_initiator == CEC_MODE_EXCL_INITIATOR) + adap->cec_initiator = fh; + else if (adap->cec_initiator == fh) + adap->cec_initiator = NULL; + fh->mode_initiator = mode_initiator; + fh->mode_follower = mode_follower; + mutex_unlock(&adap->lock); + return 0; +} + +static long cec_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) +{ + struct cec_devnode *devnode = cec_devnode_data(filp); + struct cec_fh *fh = filp->private_data; + struct cec_adapter *adap = fh->adap; + bool block = !(filp->f_flags & O_NONBLOCK); + void __user *parg = (void __user *)arg; + + if (!devnode->registered) + return -EIO; + + switch (cmd) { + case CEC_ADAP_G_CAPS: + return cec_adap_g_caps(adap, parg); + + case CEC_ADAP_G_PHYS_ADDR: + return cec_adap_g_phys_addr(adap, parg); + + case CEC_ADAP_S_PHYS_ADDR: + return cec_adap_s_phys_addr(adap, fh, block, parg); + + case CEC_ADAP_G_LOG_ADDRS: + return cec_adap_g_log_addrs(adap, parg); + + case CEC_ADAP_S_LOG_ADDRS: + return cec_adap_s_log_addrs(adap, fh, block, parg); + + case CEC_TRANSMIT: + return cec_transmit(adap, fh, block, parg); + + case CEC_RECEIVE: + return cec_receive(adap, fh, block, parg); + + case CEC_DQEVENT: + return cec_dqevent(adap, fh, block, parg); + + case CEC_G_MODE: + return cec_g_mode(adap, fh, parg); + + case CEC_S_MODE: + return cec_s_mode(adap, fh, parg); + + default: + return -ENOTTY; + } +} + +static int cec_open(struct inode *inode, struct file *filp) +{ + struct cec_devnode *devnode = + container_of(inode->i_cdev, struct cec_devnode, cdev); + struct cec_adapter *adap = to_cec_adapter(devnode); + struct cec_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL); + /* + * Initial events that are automatically sent when the cec device is + * opened. + */ + struct cec_event ev_state = { + .event = CEC_EVENT_STATE_CHANGE, + .flags = CEC_EVENT_FL_INITIAL_STATE, + }; + int err; + + if (!fh) + return -ENOMEM; + + INIT_LIST_HEAD(&fh->msgs); + INIT_LIST_HEAD(&fh->xfer_list); + mutex_init(&fh->lock); + init_waitqueue_head(&fh->wait); + + fh->mode_initiator = CEC_MODE_INITIATOR; + fh->adap = adap; + + err = cec_get_device(devnode); + if (err) { + kfree(fh); + return err; + } + + filp->private_data = fh; + + mutex_lock(&devnode->fhs_lock); + /* Queue up initial state events */ + ev_state.state_change.phys_addr = adap->phys_addr; + ev_state.state_change.log_addr_mask = adap->log_addrs.log_addr_mask; + cec_queue_event_fh(fh, &ev_state, 0); + + list_add(&fh->list, &devnode->fhs); + mutex_unlock(&devnode->fhs_lock); + + return 0; +} + +/* Override for the release function */ +static int cec_release(struct inode *inode, struct file *filp) +{ + struct cec_devnode *devnode = cec_devnode_data(filp); + struct cec_adapter *adap = to_cec_adapter(devnode); + struct cec_fh *fh = filp->private_data; + + mutex_lock(&adap->lock); + if (adap->cec_initiator == fh) + adap->cec_initiator = NULL; + if (adap->cec_follower == fh) { + adap->cec_follower = NULL; + adap->passthrough = false; + } + if (fh->mode_follower == CEC_MODE_FOLLOWER) + adap->follower_cnt--; + if (fh->mode_follower == CEC_MODE_MONITOR_ALL) + cec_monitor_all_cnt_dec(adap); + mutex_unlock(&adap->lock); + + mutex_lock(&devnode->fhs_lock); + list_del(&fh->list); + mutex_unlock(&devnode->fhs_lock); + + /* Unhook pending transmits from this filehandle. */ + mutex_lock(&adap->lock); + while (!list_empty(&fh->xfer_list)) { + struct cec_data *data = + list_first_entry(&fh->xfer_list, struct cec_data, xfer_list); + + data->blocking = false; + data->fh = NULL; + list_del(&data->xfer_list); + } + mutex_unlock(&adap->lock); + while (!list_empty(&fh->msgs)) { + struct cec_msg_entry *entry = + list_first_entry(&fh->msgs, struct cec_msg_entry, list); + + list_del(&entry->list); + kfree(entry); + } + kfree(fh); + + cec_put_device(devnode); + filp->private_data = NULL; + return 0; +} + +const struct file_operations cec_devnode_fops = { + .owner = THIS_MODULE, + .open = cec_open, + .unlocked_ioctl = cec_ioctl, + .release = cec_release, + .poll = cec_poll, + .llseek = no_llseek, +}; -- 2.45.2