ubuntu-linux-kernel/include/media/cec-pin.h

84 lines
3.1 KiB
C

/*
* cec-pin.h - low-level CEC pin control
*
* Copyright 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_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. Return true if high, false if low.
* @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: read the HPD pin. Return true if high, false if low or
* an error if negative. If NULL or -ENOTTY is returned,
* then this is not supported.
*
* These operations are used by the cec pin framework to manipulate
* the CEC pin.
*/
struct cec_pin_ops {
bool (*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);
};
/**
* 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