summaryrefslogtreecommitdiffstats
path: root/include/media/cec-pin.h
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--include/media/cec-pin.h75
1 files changed, 75 insertions, 0 deletions
diff --git a/include/media/cec-pin.h b/include/media/cec-pin.h
new file mode 100644
index 000000000..604e79cb6
--- /dev/null
+++ b/include/media/cec-pin.h
@@ -0,0 +1,75 @@
+/* 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. 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.
+ * @read_5v: read the 5V 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);
+ int (*read_5v)(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