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Diffstat (limited to 'include/media/cec-pin.h')
| -rw-r--r-- | include/media/cec-pin.h | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/include/media/cec-pin.h b/include/media/cec-pin.h new file mode 100644 index 000000000..483bc4769 --- /dev/null +++ b/include/media/cec-pin.h @@ -0,0 +1,79 @@ +/* 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 |