/* * 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