1 /*
2 * chnl.c
3 *
4 * DSP-BIOS Bridge driver support functions for TI OMAP processors.
5 *
6 * DSP API channel interface: multiplexes data streams through the single
7 * physical link managed by a Bridge Bridge driver.
8 *
9 * Copyright (C) 2005-2006 Texas Instruments, Inc.
10 *
11 * This package is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 *
15 * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
17 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
18 */
19
20 #include <linux/types.h>
21 /* ----------------------------------- Host OS */
22 #include <dspbridge/host_os.h>
23
24 /* ----------------------------------- DSP/BIOS Bridge */
25 #include <dspbridge/dbdefs.h>
26
27 /* ----------------------------------- Trace & Debug */
28 #include <dspbridge/dbc.h>
29
30 /* ----------------------------------- OS Adaptation Layer */
31 #include <dspbridge/sync.h>
32
33 /* ----------------------------------- Platform Manager */
34 #include <dspbridge/proc.h>
35 #include <dspbridge/dev.h>
36
37 /* ----------------------------------- Others */
38 #include <dspbridge/chnlpriv.h>
39 #include <chnlobj.h>
40
41 /* ----------------------------------- This */
42 #include <dspbridge/chnl.h>
43
44 /* ----------------------------------- Globals */
45 static u32 refs;
46
47 /*
48 * ======== chnl_create ========
49 * Purpose:
50 * Create a channel manager object, responsible for opening new channels
51 * and closing old ones for a given 'Bridge board.
52 */
chnl_create(struct chnl_mgr ** channel_mgr,struct dev_object * hdev_obj,const struct chnl_mgrattrs * mgr_attrts)53 int chnl_create(struct chnl_mgr **channel_mgr,
54 struct dev_object *hdev_obj,
55 const struct chnl_mgrattrs *mgr_attrts)
56 {
57 int status;
58 struct chnl_mgr *hchnl_mgr;
59 struct chnl_mgr_ *chnl_mgr_obj = NULL;
60
61 DBC_REQUIRE(refs > 0);
62 DBC_REQUIRE(channel_mgr != NULL);
63 DBC_REQUIRE(mgr_attrts != NULL);
64
65 *channel_mgr = NULL;
66
67 /* Validate args: */
68 if ((0 < mgr_attrts->max_channels) &&
69 (mgr_attrts->max_channels <= CHNL_MAXCHANNELS))
70 status = 0;
71 else if (mgr_attrts->max_channels == 0)
72 status = -EINVAL;
73 else
74 status = -ECHRNG;
75
76 if (mgr_attrts->word_size == 0)
77 status = -EINVAL;
78
79 if (!status) {
80 status = dev_get_chnl_mgr(hdev_obj, &hchnl_mgr);
81 if (!status && hchnl_mgr != NULL)
82 status = -EEXIST;
83
84 }
85
86 if (!status) {
87 struct bridge_drv_interface *intf_fxns;
88 dev_get_intf_fxns(hdev_obj, &intf_fxns);
89 /* Let Bridge channel module finish the create: */
90 status = (*intf_fxns->chnl_create) (&hchnl_mgr, hdev_obj,
91 mgr_attrts);
92 if (!status) {
93 /* Fill in DSP API channel module's fields of the
94 * chnl_mgr structure */
95 chnl_mgr_obj = (struct chnl_mgr_ *)hchnl_mgr;
96 chnl_mgr_obj->intf_fxns = intf_fxns;
97 /* Finally, return the new channel manager handle: */
98 *channel_mgr = hchnl_mgr;
99 }
100 }
101
102 DBC_ENSURE(status || chnl_mgr_obj);
103
104 return status;
105 }
106
107 /*
108 * ======== chnl_destroy ========
109 * Purpose:
110 * Close all open channels, and destroy the channel manager.
111 */
chnl_destroy(struct chnl_mgr * hchnl_mgr)112 int chnl_destroy(struct chnl_mgr *hchnl_mgr)
113 {
114 struct chnl_mgr_ *chnl_mgr_obj = (struct chnl_mgr_ *)hchnl_mgr;
115 struct bridge_drv_interface *intf_fxns;
116 int status;
117
118 DBC_REQUIRE(refs > 0);
119
120 if (chnl_mgr_obj) {
121 intf_fxns = chnl_mgr_obj->intf_fxns;
122 /* Let Bridge channel module destroy the chnl_mgr: */
123 status = (*intf_fxns->chnl_destroy) (hchnl_mgr);
124 } else {
125 status = -EFAULT;
126 }
127
128 return status;
129 }
130
131 /*
132 * ======== chnl_exit ========
133 * Purpose:
134 * Discontinue usage of the CHNL module.
135 */
chnl_exit(void)136 void chnl_exit(void)
137 {
138 DBC_REQUIRE(refs > 0);
139
140 refs--;
141
142 DBC_ENSURE(refs >= 0);
143 }
144
145 /*
146 * ======== chnl_init ========
147 * Purpose:
148 * Initialize the CHNL module's private state.
149 */
chnl_init(void)150 bool chnl_init(void)
151 {
152 bool ret = true;
153
154 DBC_REQUIRE(refs >= 0);
155
156 if (ret)
157 refs++;
158
159 DBC_ENSURE((ret && (refs > 0)) || (!ret && (refs >= 0)));
160
161 return ret;
162 }
163