From: Hans Verkuil <hans.verkuil@xxxxxxxxx> Add support for CEC notifiers, which is used to convey CEC physical address information from video drivers to their CEC counterpart driver(s). Based on an earlier version from Russell King: https://patchwork.kernel.org/patch/9277043/ The cec_notifier is a reference counted object containing the CEC physical address state of a video device. When a new notifier is registered the current state will be reported to that notifier at registration time. Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> --- MAINTAINERS | 4 +- drivers/media/Kconfig | 3 ++ drivers/media/Makefile | 4 ++ drivers/media/cec-notifier.c | 116 +++++++++++++++++++++++++++++++++++++++++++ include/media/cec-notifier.h | 93 ++++++++++++++++++++++++++++++++++ 5 files changed, 219 insertions(+), 1 deletion(-) create mode 100644 drivers/media/cec-notifier.c create mode 100644 include/media/cec-notifier.h diff --git a/MAINTAINERS b/MAINTAINERS index 83a42ef1d1a7..cfb2670aa372 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3066,7 +3066,7 @@ F: drivers/net/ieee802154/cc2520.c F: include/linux/spi/cc2520.h F: Documentation/devicetree/bindings/net/ieee802154/cc2520.txt -CEC DRIVER +CEC FRAMEWORK M: Hans Verkuil <hans.verkuil@xxxxxxxxx> L: linux-media@xxxxxxxxxxxxxxx T: git git://linuxtv.org/media_tree.git @@ -3076,9 +3076,11 @@ F: Documentation/media/kapi/cec-core.rst F: Documentation/media/uapi/cec F: drivers/media/cec/ F: drivers/media/cec-edid.c +F: drivers/media/cec-notifier.c F: drivers/media/rc/keymaps/rc-cec.c F: include/media/cec.h F: include/media/cec-edid.h +F: include/media/cec-notifier.h F: include/uapi/linux/cec.h F: include/uapi/linux/cec-funcs.h diff --git a/drivers/media/Kconfig b/drivers/media/Kconfig index 3512316e7a46..799429f51d1a 100644 --- a/drivers/media/Kconfig +++ b/drivers/media/Kconfig @@ -99,6 +99,9 @@ config MEDIA_CEC_DEBUG config MEDIA_CEC_EDID bool +config MEDIA_CEC_NOTIFIER + bool + # # Media controller # Selectable only for webcam/grabbers, as other drivers don't use it diff --git a/drivers/media/Makefile b/drivers/media/Makefile index d87ccb8eeabe..8b36a571d443 100644 --- a/drivers/media/Makefile +++ b/drivers/media/Makefile @@ -6,6 +6,10 @@ ifeq ($(CONFIG_MEDIA_CEC_EDID),y) obj-$(CONFIG_MEDIA_SUPPORT) += cec-edid.o endif +ifeq ($(CONFIG_MEDIA_CEC_NOTIFIER),y) + obj-$(CONFIG_MEDIA_SUPPORT) += cec-notifier.o +endif + ifeq ($(CONFIG_MEDIA_CEC_SUPPORT),y) obj-$(CONFIG_MEDIA_SUPPORT) += cec/ endif diff --git a/drivers/media/cec-notifier.c b/drivers/media/cec-notifier.c new file mode 100644 index 000000000000..a5938c4d3ab4 --- /dev/null +++ b/drivers/media/cec-notifier.c @@ -0,0 +1,116 @@ +/* + * cec-notifier.c - notify CEC drivers of physical address changes + * + * Copyright 2016 Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> + * Copyright 2016-2017 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/export.h> +#include <linux/string.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/kref.h> + +#include <media/cec-notifier.h> + +struct cec_notifier { + struct mutex lock; + struct list_head head; + struct kref kref; + struct device *dev; + struct cec_adapter *cec_adap; + void (*callback)(struct cec_adapter *adap, u16 pa); + + u16 phys_addr; +}; + +static LIST_HEAD(cec_notifiers); +static DEFINE_MUTEX(cec_notifiers_lock); + +struct cec_notifier *cec_notifier_get(struct device *dev) +{ + struct cec_notifier *n; + + mutex_lock(&cec_notifiers_lock); + list_for_each_entry(n, &cec_notifiers, head) { + if (n->dev == dev) { + mutex_unlock(&cec_notifiers_lock); + kref_get(&n->kref); + return n; + } + } + n = kzalloc(sizeof(*n), GFP_KERNEL); + if (!n) + goto unlock; + n->dev = dev; + n->phys_addr = CEC_PHYS_ADDR_INVALID; + mutex_init(&n->lock); + kref_init(&n->kref); + list_add_tail(&n->head, &cec_notifiers); +unlock: + mutex_unlock(&cec_notifiers_lock); + return n; +} +EXPORT_SYMBOL_GPL(cec_notifier_get); + +static void cec_notifier_release(struct kref *kref) +{ + struct cec_notifier *n = + container_of(kref, struct cec_notifier, kref); + + list_del(&n->head); + kfree(n); +} + +void cec_notifier_put(struct cec_notifier *n) +{ + mutex_lock(&cec_notifiers_lock); + kref_put(&n->kref, cec_notifier_release); + mutex_unlock(&cec_notifiers_lock); +} +EXPORT_SYMBOL_GPL(cec_notifier_put); + +void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa) +{ + mutex_lock(&n->lock); + n->phys_addr = pa; + if (n->callback) + n->callback(n->cec_adap, n->phys_addr); + mutex_unlock(&n->lock); +} +EXPORT_SYMBOL_GPL(cec_notifier_set_phys_addr); + +void cec_notifier_register(struct cec_notifier *n, + struct cec_adapter *adap, + void (*callback)(struct cec_adapter *adap, u16 pa)) +{ + kref_get(&n->kref); + mutex_lock(&n->lock); + n->cec_adap = adap; + n->callback = callback; + n->callback(adap, n->phys_addr); + mutex_unlock(&n->lock); +} +EXPORT_SYMBOL_GPL(cec_notifier_register); + +void cec_notifier_unregister(struct cec_notifier *n) +{ + mutex_lock(&n->lock); + n->callback = NULL; + mutex_unlock(&n->lock); + cec_notifier_put(n); +} +EXPORT_SYMBOL_GPL(cec_notifier_unregister); diff --git a/include/media/cec-notifier.h b/include/media/cec-notifier.h new file mode 100644 index 000000000000..79ad3a48361c --- /dev/null +++ b/include/media/cec-notifier.h @@ -0,0 +1,93 @@ +/* + * cec-notifier.h - notify CEC drivers of physical address changes + * + * Copyright 2016 Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> + * Copyright 2016-2017 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 LINUX_CEC_NOTIFIER_H +#define LINUX_CEC_NOTIFIER_H + +#include <linux/types.h> +#include <media/cec-edid.h> + +struct device; +struct cec_adapter; +struct cec_notifier; + +#ifdef CONFIG_MEDIA_CEC_NOTIFIER + +/** + * cec_notifier_get - find or create a new cec_notifier for the given device. + * @dev: device that sends the events. + * + * If a notifier for device @dev already exists, then increase the refcount + * and return that notifier. + * + * If it doesn't exist, then allocate a new notifier struct and return a + * pointer to that new struct. + * + * Return NULL if the memory could not be allocated. + */ +struct cec_notifier *cec_notifier_get(struct device *dev); + +/** + * cec_notifier_put - decrease refcount and delete when the refcount reaches 0. + * @n: notifier + */ +void cec_notifier_put(struct cec_notifier *n); + +/** + * cec_notifier_set_phys_addr - set a new physical address. + * @n: the CEC notifier + * + * Set a new CEC physical address. + */ +void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa); + +/** + * cec_notifier_register - register a callback with the notifier + * @n: the CEC notifier + * @adap: the CEC adapter, passed as argument to the callback function + * @callback: the callback function + */ +void cec_notifier_register(struct cec_notifier *n, + struct cec_adapter *adap, + void (*callback)(struct cec_adapter *adap, u16 pa)); + +/** + * cec_notifier_unregister - unregister the callback from the notifier. + * @n: the CEC notifier + */ +void cec_notifier_unregister(struct cec_notifier *n); + +#else +static inline struct cec_notifier *cec_notifier_get(struct device *dev) +{ + /* A non-NULL pointer is expected on success */ + return (struct cec_notifier *)0xdeadfeed; +} + +static inline void cec_notifier_put(struct cec_notifier *n) +{ +} + +static inline void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa) +{ +} +#endif + +#endif -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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