spivar.h revision 1.17 1 /* $NetBSD: spivar.h,v 1.17 2025/09/10 02:06:26 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2006 Urbana-Champaign Independent Media Center.
5 * Copyright (c) 2006 Garrett D'Amore.
6 * All rights reserved.
7 *
8 * Portions of this code were written by Garrett D'Amore for the
9 * Champaign-Urbana Community Wireless Network Project.
10 *
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
13 * conditions are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above
17 * copyright notice, this list of conditions and the following
18 * disclaimer in the documentation and/or other materials provided
19 * with the distribution.
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgements:
22 * This product includes software developed by the Urbana-Champaign
23 * Independent Media Center.
24 * This product includes software developed by Garrett D'Amore.
25 * 4. Urbana-Champaign Independent Media Center's name and Garrett
26 * D'Amore's name may not be used to endorse or promote products
27 * derived from this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE URBANA-CHAMPAIGN INDEPENDENT
30 * MEDIA CENTER AND GARRETT D'AMORE ``AS IS'' AND ANY EXPRESS OR
31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
32 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE URBANA-CHAMPAIGN INDEPENDENT
34 * MEDIA CENTER OR GARRETT D'AMORE BE LIABLE FOR ANY DIRECT, INDIRECT,
35 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
38 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
41 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 */
43
44 #ifndef _DEV_SPI_SPIVAR_H_
45 #define _DEV_SPI_SPIVAR_H_
46
47 #include <sys/queue.h>
48
49 /*
50 * Serial Peripheral Interface bus. This is a 4-wire bus common for
51 * connecting flash, clocks, sensors, and various other low-speed
52 * peripherals.
53 */
54
55 struct spi_handle;
56 struct spi_transfer;
57
58 #define SPI_MODE_CPHA __BIT(0)
59 #define SPI_MODE_CPOL __BIT(1)
60
61 /*
62 * De facto standard latching modes.
63 */
64 #define SPI_MODE_0 0
65 #define SPI_MODE_1 SPI_MODE_CPHA
66 #define SPI_MODE_2 SPI_MODE_CPOL
67 #define SPI_MODE_3 (SPI_MODE_CPHA | SPI_MODE_CPOL)
68
69 /* Philips' Microwire is just Mode 0 */
70 #define SPI_MODE_MICROWIRE SPI_MODE_0
71
72 /* SPI transfer speed helper macros -- converts to Hz for spi_configure(). */
73 #define SPI_FREQ_kHz(x) ((x) * 1000)
74 #define SPI_FREQ_MHz(x) ((x) * 1000000)
75
76 struct spi_controller {
77 void *sct_cookie; /* controller private data */
78 int sct_nslaves;
79 int (*sct_configure)(void *, int, int, int);
80 int (*sct_transfer)(void *, struct spi_transfer *);
81 };
82
83 int spibus_print(void *, const char *);
84
85 /* one per chip select */
86 struct spibus_attach_args {
87 struct spi_controller *sba_controller;
88 prop_array_t sba_child_devices;
89 };
90
91 struct spi_attach_args {
92 struct spi_handle *sa_handle;
93 /* only set if using direct config */
94 int sa_ncompat; /* number of pointers in the
95 ia_compat array */
96 const char ** sa_compat; /* chip names */
97 prop_dictionary_t sa_prop; /* dictionary for this device */
98
99 uintptr_t sa_cookie; /* OF node in openfirmware machines */
100 };
101
102 /*
103 * This is similar in some respects to struct buf, but we cannot use
104 * that structure because it was not designed to support full-duplex
105 * IO.
106 */
107 struct spi_chunk {
108 struct spi_chunk *chunk_next;
109 int chunk_count;
110 uint8_t *chunk_read;
111 const uint8_t *chunk_write;
112 /* for private use by framework and bus driver */
113 uint8_t *chunk_rptr;
114 const uint8_t *chunk_wptr;
115 int chunk_rresid;
116 int chunk_wresid;
117 };
118
119 struct spi_transfer {
120 struct spi_chunk *st_chunks; /* chained bufs */
121 SIMPLEQ_ENTRY(spi_transfer) st_chain; /* chain of submitted jobs */
122 volatile int st_flags;
123 int st_errno;
124 int st_slave;
125 void *st_private;
126 void (*st_done)(struct spi_transfer *);
127 kmutex_t st_lock;
128 kcondvar_t st_cv;
129 void *st_busprivate;
130 void *st_spiprivate;
131 };
132
133 /* declare a list of transfers */
134 SIMPLEQ_HEAD(spi_transq, spi_transfer);
135
136 #define spi_transq_init(q) \
137 SIMPLEQ_INIT(q)
138
139 #define spi_transq_enqueue(q, trans) \
140 SIMPLEQ_INSERT_TAIL(q, trans, st_chain)
141
142 #define spi_transq_dequeue(q) \
143 SIMPLEQ_REMOVE_HEAD(q, st_chain)
144
145 #define spi_transq_first(q) \
146 SIMPLEQ_FIRST(q)
147
148 #define SPI_F_DONE 0x0001
149 #define SPI_F_ERROR 0x0002
150
151 static inline device_t
152 spibus_attach(device_t dev, struct spi_controller *sct)
153 {
154 struct spibus_attach_args sba = {
155 .sba_controller = sct,
156 };
157 return config_found(dev, &sba, spibus_print,
158 CFARGS(.iattr = "spibus",
159 .devhandle = device_handle(dev)));
160 }
161
162 int spi_compatible_match(const struct spi_attach_args *, const cfdata_t,
163 const struct device_compatible_entry *);
164 const struct device_compatible_entry *
165 spi_compatible_lookup(const struct spi_attach_args *,
166 const struct device_compatible_entry *);
167 int spi_configure(device_t, struct spi_handle *, int, int);
168 int spi_transfer(struct spi_handle *, struct spi_transfer *);
169 void spi_transfer_init(struct spi_transfer *);
170 void spi_chunk_init(struct spi_chunk *, int, const uint8_t *, uint8_t *);
171 void spi_transfer_add(struct spi_transfer *, struct spi_chunk *);
172 void spi_wait(struct spi_transfer *);
173 void spi_done(struct spi_transfer *, int);
174
175 /* convenience wrappers */
176 int spi_send(struct spi_handle *, int, const uint8_t *);
177 int spi_recv(struct spi_handle *, int, uint8_t *);
178 int spi_send_recv(struct spi_handle *, int, const uint8_t *, int,
179 uint8_t *);
180
181 #endif /* _DEV_SPI_SPIVAR_H_ */
182