Am Dienstag, den 13.12.2016, 16:08 +0100 schrieb Hans Verkuil: > From: Hans Verkuil <hans.verkuil@xxxxxxxxx> > > Add support for HDMI hotplug and EDID notifiers, which is used to convey > information from HDMI drivers to their CEC and audio counterparts. > > Based on an earlier version from Russell King: > > https://patchwork.kernel.org/patch/9277043/ > > The hdmi_notifier is a reference counted object containing the HDMI state > of an HDMI 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> Acked-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> regards Philipp > --- > drivers/video/Kconfig | 3 + > drivers/video/Makefile | 1 + > drivers/video/hdmi-notifier.c | 134 ++++++++++++++++++++++++++++++++++++++++++ > include/linux/hdmi-notifier.h | 109 ++++++++++++++++++++++++++++++++++ > 4 files changed, 247 insertions(+) > create mode 100644 drivers/video/hdmi-notifier.c > create mode 100644 include/linux/hdmi-notifier.h > > diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig > index 3c20af9..1ee7b9f 100644 > --- a/drivers/video/Kconfig > +++ b/drivers/video/Kconfig > @@ -36,6 +36,9 @@ config VIDEOMODE_HELPERS > config HDMI > bool > > +config HDMI_NOTIFIERS > + bool > + > if VT > source "drivers/video/console/Kconfig" > endif > diff --git a/drivers/video/Makefile b/drivers/video/Makefile > index 9ad3c17..65f5649 100644 > --- a/drivers/video/Makefile > +++ b/drivers/video/Makefile > @@ -1,5 +1,6 @@ > obj-$(CONFIG_VGASTATE) += vgastate.o > obj-$(CONFIG_HDMI) += hdmi.o > +obj-$(CONFIG_HDMI_NOTIFIERS) += hdmi-notifier.o > > obj-$(CONFIG_VT) += console/ > obj-$(CONFIG_LOGO) += logo/ > diff --git a/drivers/video/hdmi-notifier.c b/drivers/video/hdmi-notifier.c > new file mode 100644 > index 0000000..29e4225 > --- /dev/null > +++ b/drivers/video/hdmi-notifier.c > @@ -0,0 +1,134 @@ > +#include <linux/export.h> > +#include <linux/hdmi-notifier.h> > +#include <linux/string.h> > +#include <linux/slab.h> > +#include <linux/list.h> > + > +static LIST_HEAD(hdmi_notifiers); > +static DEFINE_MUTEX(hdmi_notifiers_lock); > + > +struct hdmi_notifier *hdmi_notifier_get(struct device *dev) > +{ > + struct hdmi_notifier *n; > + > + mutex_lock(&hdmi_notifiers_lock); > + list_for_each_entry(n, &hdmi_notifiers, head) { > + if (n->dev == dev) { > + mutex_unlock(&hdmi_notifiers_lock); > + kref_get(&n->kref); > + return n; > + } > + } > + n = kzalloc(sizeof(*n), GFP_KERNEL); > + if (!n) > + goto unlock; > + n->dev = dev; > + mutex_init(&n->lock); > + BLOCKING_INIT_NOTIFIER_HEAD(&n->notifiers); > + kref_init(&n->kref); > + list_add_tail(&n->head, &hdmi_notifiers); > +unlock: > + mutex_unlock(&hdmi_notifiers_lock); > + return n; > +} > +EXPORT_SYMBOL_GPL(hdmi_notifier_get); > + > +static void hdmi_notifier_release(struct kref *kref) > +{ > + struct hdmi_notifier *n = > + container_of(kref, struct hdmi_notifier, kref); > + > + mutex_lock(&hdmi_notifiers_lock); > + list_del(&n->head); > + mutex_unlock(&hdmi_notifiers_lock); > + kfree(n->edid); > + kfree(n); > +} > + > +void hdmi_notifier_put(struct hdmi_notifier *n) > +{ > + kref_put(&n->kref, hdmi_notifier_release); > +} > +EXPORT_SYMBOL_GPL(hdmi_notifier_put); > + > +int hdmi_notifier_register(struct hdmi_notifier *n, struct notifier_block *nb) > +{ > + int ret = blocking_notifier_chain_register(&n->notifiers, nb); > + > + if (ret) > + return ret; > + kref_get(&n->kref); > + mutex_lock(&n->lock); > + if (n->connected) { > + blocking_notifier_call_chain(&n->notifiers, HDMI_CONNECTED, n); > + if (n->edid_size) > + blocking_notifier_call_chain(&n->notifiers, HDMI_NEW_EDID, n); > + if (n->has_eld) > + blocking_notifier_call_chain(&n->notifiers, HDMI_NEW_ELD, n); > + } > + mutex_unlock(&n->lock); > + return 0; > +} > +EXPORT_SYMBOL_GPL(hdmi_notifier_register); > + > +int hdmi_notifier_unregister(struct hdmi_notifier *n, struct notifier_block *nb) > +{ > + int ret = blocking_notifier_chain_unregister(&n->notifiers, nb); > + > + if (ret == 0) > + hdmi_notifier_put(n); > + return ret; > +} > +EXPORT_SYMBOL_GPL(hdmi_notifier_unregister); > + > +void hdmi_event_connect(struct hdmi_notifier *n) > +{ > + mutex_lock(&n->lock); > + n->connected = true; > + blocking_notifier_call_chain(&n->notifiers, HDMI_CONNECTED, n); > + mutex_unlock(&n->lock); > +} > +EXPORT_SYMBOL_GPL(hdmi_event_connect); > + > +void hdmi_event_disconnect(struct hdmi_notifier *n) > +{ > + mutex_lock(&n->lock); > + n->connected = false; > + n->has_eld = false; > + n->edid_size = 0; > + blocking_notifier_call_chain(&n->notifiers, HDMI_DISCONNECTED, n); > + mutex_unlock(&n->lock); > +} > +EXPORT_SYMBOL_GPL(hdmi_event_disconnect); > + > +int hdmi_event_new_edid(struct hdmi_notifier *n, const void *edid, size_t size) > +{ > + mutex_lock(&n->lock); > + if (n->edid_allocated_size < size) { > + void *p = kmalloc(size, GFP_KERNEL); > + > + if (p == NULL) { > + mutex_unlock(&n->lock); > + return -ENOMEM; > + } > + kfree(n->edid); > + n->edid = p; > + n->edid_allocated_size = size; > + } > + memcpy(n->edid, edid, size); > + n->edid_size = size; > + blocking_notifier_call_chain(&n->notifiers, HDMI_NEW_EDID, n); > + mutex_unlock(&n->lock); > + return 0; > +} > +EXPORT_SYMBOL_GPL(hdmi_event_new_edid); > + > +void hdmi_event_new_eld(struct hdmi_notifier *n, const u8 eld[128]) > +{ > + mutex_lock(&n->lock); > + memcpy(n->eld, eld, sizeof(n->eld)); > + n->has_eld = true; > + blocking_notifier_call_chain(&n->notifiers, HDMI_NEW_ELD, n); > + mutex_unlock(&n->lock); > +} > +EXPORT_SYMBOL_GPL(hdmi_event_new_eld); > diff --git a/include/linux/hdmi-notifier.h b/include/linux/hdmi-notifier.h > new file mode 100644 > index 0000000..1d88db0 > --- /dev/null > +++ b/include/linux/hdmi-notifier.h > @@ -0,0 +1,109 @@ > +/* > + * hdmi-notifier.h - notify interested parties of (dis)connect and EDID > + * events > + * > + * Copyright 2016 Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> > + * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved. > + */ > + > +#ifndef LINUX_HDMI_NOTIFIER_H > +#define LINUX_HDMI_NOTIFIER_H > + > +#include <linux/types.h> > +#include <linux/notifier.h> > +#include <linux/kref.h> > + > +enum { > + HDMI_CONNECTED, > + HDMI_DISCONNECTED, > + HDMI_NEW_EDID, > + HDMI_NEW_ELD, > +}; > + > +struct device; > + > +struct hdmi_notifier { > + struct mutex lock; > + struct list_head head; > + struct kref kref; > + struct blocking_notifier_head notifiers; > + struct device *dev; > + > + /* Current state */ > + bool connected; > + bool has_eld; > + unsigned char eld[128]; > + void *edid; > + size_t edid_size; > + size_t edid_allocated_size; > +}; > + > +/** > + * hdmi_notifier_get - find or create a new hdmi_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 hdmi_notifier *hdmi_notifier_get(struct device *dev); > + > +/** > + * hdmi_notifier_put - decrease refcount and delete when the refcount reaches 0. > + * @n: notifier > + */ > +void hdmi_notifier_put(struct hdmi_notifier *n); > + > +/** > + * hdmi_notifier_register - register the notifier with the notifier_block. > + * @n: the HDMI notifier > + * @nb: the notifier_block > + */ > +int hdmi_notifier_register(struct hdmi_notifier *n, struct notifier_block *nb); > + > +/** > + * hdmi_notifier_unregister - unregister the notifier with the notifier_block. > + * @n: the HDMI notifier > + * @nb: the notifier_block > + */ > +int hdmi_notifier_unregister(struct hdmi_notifier *n, struct notifier_block *nb); > + > +/** > + * hdmi_event_connect - send a connect event. > + * @n: the HDMI notifier > + * > + * Send an HDMI_CONNECTED event to any registered parties. > + */ > +void hdmi_event_connect(struct hdmi_notifier *n); > + > +/** > + * hdmi_event_disconnect - send a disconnect event. > + * @n: the HDMI notifier > + * > + * Send an HDMI_DISCONNECTED event to any registered parties. > + */ > +void hdmi_event_disconnect(struct hdmi_notifier *n); > + > +/** > + * hdmi_event_new_edid - send a new EDID event. > + * @n: the HDMI notifier > + * > + * Send an HDMI_NEW_EDID event to any registered parties. > + * This function will make a copy the EDID so it can return -ENOMEM if > + * no memory could be allocated. > + */ > +int hdmi_event_new_edid(struct hdmi_notifier *n, const void *edid, size_t size); > + > +/** > + * hdmi_event_new_eld - send a new ELD event. > + * @n: the HDMI notifier > + * > + * Send an HDMI_NEW_ELD event to any registered parties. > + */ > +void hdmi_event_new_eld(struct hdmi_notifier *n, const u8 eld[128]); > + > +#endif -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
