This is extracted from Russell's food for thought HDMI notification prototype [1]. I've put it into drivers/video for the time being because my kernels don't have drivers/cec yet.
The current use case for the notifications on MediaTek MT8173 is to let the (dis)connection notifications control an ALSA jack object.
No Signed-off-by yet since this is not my code, and up for discussion.
[1] https://patchwork.kernel.org/patch/7339011/ --- drivers/video/Makefile | 2 +- drivers/video/hdmi-not.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/hdmi-not.h | 39 +++++++++++++++++++++++++++++++ 3 files changed, 101 insertions(+), 1 deletion(-) create mode 100644 drivers/video/hdmi-not.c create mode 100644 include/linux/hdmi-not.h
diff --git a/drivers/video/Makefile b/drivers/video/Makefile index 9ad3c17..bf25760 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -1,5 +1,5 @@ obj-$(CONFIG_VGASTATE) += vgastate.o -obj-$(CONFIG_HDMI) += hdmi.o +obj-$(CONFIG_HDMI) += hdmi.o hdmi-not.o
obj-$(CONFIG_VT) += console/ obj-$(CONFIG_LOGO) += logo/ diff --git a/drivers/video/hdmi-not.c b/drivers/video/hdmi-not.c new file mode 100644 index 0000000..ba3be8a --- /dev/null +++ b/drivers/video/hdmi-not.c @@ -0,0 +1,61 @@ +#include <linux/export.h> +#include <linux/hdmi-not.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 void *eld) +{ + 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-not.h b/include/linux/hdmi-not.h new file mode 100644 index 0000000..940ece45 --- /dev/null +++ b/include/linux/hdmi-not.h @@ -0,0 +1,39 @@ +#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 void *eld);