[PATCH RFC 1/5] video: add HDMI state notifier support

[Hans Verkuil]

On 08/12/2016 04:14 PM, Russell King wrote:
> Add support for HDMI hotplug and EDID notifiers, which is used to convey
> information from HDMI drivers to their CEC and audio counterparts.
>
> Acked-by: Philipp Zabel <p.zabel at pengutronix.de>

I still don't really like the void *, but not enough to block this, so:

Acked-by: Hans Verkuil <hans.verkuil at cisco.com>

Regards,

	Hans

> Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
> ---
>  drivers/video/Kconfig         |  3 +++
>  drivers/video/Makefile        |  1 +
>  drivers/video/hdmi-notifier.c | 61 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/hdmi-notifier.h | 44 +++++++++++++++++++++++++++++++
>  4 files changed, 109 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 3c20af999893..1ee7b9f9bb25 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 9ad3c17d6456..65f564906fb4 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 000000000000..f3b16552b0fe
> --- /dev/null
> +++ b/drivers/video/hdmi-notifier.c
> @@ -0,0 +1,61 @@
> +#include <linux/export.h>
> +#include <linux/hdmi-notifier.h>
> +#include <linux/notifier.h>
> +#include <linux/string.h>
> +
> +static BLOCKING_NOTIFIER_HEAD(hdmi_notifier);
> +
> +int hdmi_register_notifier(struct notifier_block *nb)
> +{
> +	return blocking_notifier_chain_register(&hdmi_notifier, nb);
> +}
> +EXPORT_SYMBOL_GPL(hdmi_register_notifier);
> +
> +int hdmi_unregister_notifier(struct notifier_block *nb)
> +{
> +	return blocking_notifier_chain_unregister(&hdmi_notifier, nb);
> +}
> +EXPORT_SYMBOL_GPL(hdmi_unregister_notifier);
> +
> +void hdmi_event_connect(struct device *dev)
> +{
> +	struct hdmi_event_base base;
> +
> +	base.source = dev;
> +
> +	blocking_notifier_call_chain(&hdmi_notifier, HDMI_CONNECTED, &base);
> +}
> +EXPORT_SYMBOL_GPL(hdmi_event_connect);
> +
> +void hdmi_event_disconnect(struct device *dev)
> +{
> +	struct hdmi_event_base base;
> +
> +	base.source = dev;
> +
> +	blocking_notifier_call_chain(&hdmi_notifier, HDMI_DISCONNECTED, &base);
> +}
> +EXPORT_SYMBOL_GPL(hdmi_event_disconnect);
> +
> +void hdmi_event_new_edid(struct device *dev, const void *edid, size_t size)
> +{
> +	struct hdmi_event_new_edid new_edid;
> +
> +	new_edid.base.source = dev;
> +	new_edid.edid = edid;
> +	new_edid.size = size;
> +
> +	blocking_notifier_call_chain(&hdmi_notifier, HDMI_NEW_EDID, &new_edid);
> +}
> +EXPORT_SYMBOL_GPL(hdmi_event_new_edid);
> +
> +void hdmi_event_new_eld(struct device *dev, const u8 eld[128])
> +{
> +	struct hdmi_event_new_eld new_eld;
> +
> +	new_eld.base.source = dev;
> +	memcpy(new_eld.eld, eld, sizeof(new_eld.eld));
> +
> +	blocking_notifier_call_chain(&hdmi_notifier, HDMI_NEW_ELD, &new_eld);
> +}
> +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 000000000000..5fb710e5d68a
> --- /dev/null
> +++ b/include/linux/hdmi-notifier.h
> @@ -0,0 +1,44 @@
> +#ifndef LINUX_HDMI_NOTIFIER_H
> +#define LINUX_HDMI_NOTIFIER_H
> +
> +#include <linux/types.h>
> +
> +enum {
> +	HDMI_CONNECTED,
> +	HDMI_DISCONNECTED,
> +	HDMI_NEW_EDID,
> +	HDMI_NEW_ELD,
> +};
> +
> +struct hdmi_event_base {
> +	struct device *source;
> +};
> +
> +struct hdmi_event_new_edid {
> +	struct hdmi_event_base base;
> +	const void *edid;
> +	size_t size;
> +};
> +
> +struct hdmi_event_new_eld {
> +	struct hdmi_event_base base;
> +	unsigned char eld[128];
> +};
> +
> +union hdmi_event {
> +	struct hdmi_event_base base;
> +	struct hdmi_event_new_edid edid;
> +	struct hdmi_event_new_eld eld;
> +};
> +
> +struct notifier_block;
> +
> +int hdmi_register_notifier(struct notifier_block *nb);
> +int hdmi_unregister_notifier(struct notifier_block *nb);
> +
> +void hdmi_event_connect(struct device *dev);
> +void hdmi_event_disconnect(struct device *dev);
> +void hdmi_event_new_edid(struct device *dev, const void *edid, size_t size);
> +void hdmi_event_new_eld(struct device *dev, const u8 eld[128]);
> +
> +#endif
>