xref: /netbsd-src/sys/dev/fdt/fdt_port.h (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: fdt_port.h,v 1.1 2018/04/03 12:40:20 bouyer Exp $	*/
2 
3 /*-
4  * Copyright (c) 2018 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Manuel Bouyer.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * ports and endpoints management. from
34  * linux/Documentation/devicetree/bindings/graph.txt
35  * 2 endpoints can be connected together in the device tree. In this case
36  * an endpoint will have a remote endpoint.
37  * A pair of connected endpoints can be activated by a driver; when it choose
38  * to use this path.
39  * A pair of active endpoints can be enabled; when a driver starts to send
40  * a signal. Disabling a pair of endpoints can cause appropriate actions
41  * to save power (stop clocks, disable output buffers, turn on/off power, ...)
42  */
43 
44 #ifndef _DEV_FDT_FDT_PORT_H_
45 #define _DEV_FDT_FDT_PORT_H_
46 
47 struct fdt_port;
48 struct fdt_endpoint;
49 
50 struct fdt_device_ports {
51 	struct fdt_port *dp_port; /* this device's ports */
52 	int		dp_nports; /* number of ports for this device */
53 	device_t	dp_dev;
54 	/* callbacks to device drivers owning endpoints */
55 	void		(*dp_ep_connect)(device_t, struct fdt_endpoint *, bool);
56 	int		(*dp_ep_activate)(device_t, struct fdt_endpoint *, bool);
57 	int		(*dp_ep_enable)(device_t, struct fdt_endpoint *, bool);
58 	void *		(*dp_ep_get_data)(device_t, struct fdt_endpoint *);
59 	SLIST_ENTRY(fdt_device_ports) dp_list;
60 };
61 
62 enum endpoint_type {
63 	EP_OTHER = 0,
64 	EP_CONNECTOR,
65 	EP_PANEL,
66 };
67 
68 
69 /*
70  * register a device's ports and enpoints into the provided fdt_device_ports.
71  * when and endpoint is connected to a remote endpoint, dp_ep_connect
72  * is called for the devices associated to both endpoints
73  */
74 int fdt_ports_register(struct fdt_device_ports *, device_t,
75 					int, enum endpoint_type);
76 
77 /* various methods to retrive an enpoint descriptor */
78 struct fdt_endpoint *fdt_endpoint_get_from_phandle(int);
79 struct fdt_endpoint *fdt_endpoint_get_from_index(struct fdt_device_ports *,
80 							int, int);
81 struct fdt_endpoint *fdt_endpoint_remote(struct fdt_endpoint *);
82 
83 /*
84  * get informations/data for a given endpoint
85  */
86 int fdt_endpoint_port_index(struct fdt_endpoint *);
87 int fdt_endpoint_index(struct fdt_endpoint *);
88 device_t fdt_endpoint_device(struct fdt_endpoint *);
89 bool fdt_endpoint_is_active(struct fdt_endpoint *);
90 bool fdt_endpoint_is_enabled(struct fdt_endpoint *);
91 /*
92  * call dp_ep_get_data() for the endpoint. The returned pointer is
93  * type of driver-specific.
94  */
95 void * fdt_endpoint_get_data(struct fdt_endpoint *);
96 
97 /*
98  * Activate/deactivate an endpoint. This causes dp_ep_activate() to be
99  * called for the remote endpoint
100  */
101 int fdt_endpoint_activate(struct fdt_endpoint *, bool);
102 /*
103  * Enable/disable an endpoint. This causes dp_ep_enable() to be called for
104  * the remote endpoint
105  */
106 int fdt_endpoint_enable(struct fdt_endpoint *, bool);
107 
108 #endif /* _DEV_FDT_FDT_PORT_H_ */
109