https://github.com/torvalds/linux
Tip revision: 3123109284176b1532874591f7c81f3837bbdc17 authored by Linus Torvalds on 03 April 2022, 21:08:21 UTC
Linux 5.18-rc1
Linux 5.18-rc1
Tip revision: 3123109
cec-pin.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* cec-pin.h - low-level CEC pin control
*
* Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
*/
#ifndef LINUX_CEC_PIN_H
#define LINUX_CEC_PIN_H
#include <linux/types.h>
#include <media/cec.h>
/**
* struct cec_pin_ops - low-level CEC pin operations
* @read: read the CEC pin. Returns > 0 if high, 0 if low, or an error
* if negative.
* @low: drive the CEC pin low.
* @high: stop driving the CEC pin. The pull-up will drive the pin
* high, unless someone else is driving the pin low.
* @enable_irq: optional, enable the interrupt to detect pin voltage changes.
* @disable_irq: optional, disable the interrupt.
* @free: optional. Free any allocated resources. Called when the
* adapter is deleted.
* @status: optional, log status information.
* @read_hpd: optional. Read the HPD pin. Returns > 0 if high, 0 if low or
* an error if negative.
* @read_5v: optional. Read the 5V pin. Returns > 0 if high, 0 if low or
* an error if negative.
* @received: optional. High-level CEC message callback. Allows the driver
* to process CEC messages.
*
* These operations (except for the @received op) are used by the
* cec pin framework to manipulate the CEC pin.
*/
struct cec_pin_ops {
int (*read)(struct cec_adapter *adap);
void (*low)(struct cec_adapter *adap);
void (*high)(struct cec_adapter *adap);
bool (*enable_irq)(struct cec_adapter *adap);
void (*disable_irq)(struct cec_adapter *adap);
void (*free)(struct cec_adapter *adap);
void (*status)(struct cec_adapter *adap, struct seq_file *file);
int (*read_hpd)(struct cec_adapter *adap);
int (*read_5v)(struct cec_adapter *adap);
/* High-level CEC message callback */
int (*received)(struct cec_adapter *adap, struct cec_msg *msg);
};
/**
* cec_pin_changed() - update pin state from interrupt
*
* @adap: pointer to the cec adapter
* @value: when true the pin is high, otherwise it is low
*
* If changes of the CEC voltage are detected via an interrupt, then
* cec_pin_changed is called from the interrupt with the new value.
*/
void cec_pin_changed(struct cec_adapter *adap, bool value);
/**
* cec_pin_allocate_adapter() - allocate a pin-based cec adapter
*
* @pin_ops: low-level pin operations
* @priv: will be stored in adap->priv and can be used by the adapter ops.
* Use cec_get_drvdata(adap) to get the priv pointer.
* @name: the name of the CEC adapter. Note: this name will be copied.
* @caps: capabilities of the CEC adapter. This will be ORed with
* CEC_CAP_MONITOR_ALL and CEC_CAP_MONITOR_PIN.
*
* Allocate a cec adapter using the cec pin framework.
*
* Return: a pointer to the cec adapter or an error pointer
*/
struct cec_adapter *cec_pin_allocate_adapter(const struct cec_pin_ops *pin_ops,
void *priv, const char *name, u32 caps);
#endif