i2cvar.h revision 1.26 1 /* $NetBSD: i2cvar.h,v 1.26 2022/10/24 10:17:27 riastradh Exp $ */
2
3 /*
4 * Copyright (c) 2003 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Steve C. Woodford and Jason R. Thorpe for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed for the NetBSD Project by
20 * Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 * or promote products derived from this software without specific prior
23 * written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38 #ifndef _DEV_I2C_I2CVAR_H_
39 #define _DEV_I2C_I2CVAR_H_
40
41 #include <sys/device.h>
42 #include <sys/mutex.h>
43 #include <dev/i2c/i2c_io.h>
44 #include <prop/proplib.h>
45
46 /* Flags passed to i2c routines. */
47 #define I2C_F_WRITE 0 /* new transfer is a write */
48 #define I2C_F_READ __BIT(0) /* new transfer is a read */
49 #define I2C_F_LAST __BIT(1) /* last byte of read */
50 #define I2C_F_STOP __BIT(2) /* send stop after byte */
51 #define I2C_F_POLL __BIT(3) /* poll, don't sleep */
52 #define I2C_F_PEC __BIT(4) /* smbus packet error checking */
53 #define I2C_F_SPEED __BITS(28,31) /* I2C transfer speed selector */
54
55 #define I2C_SPEED_SM 0 /* standard mode (100Kb/s) */
56 #define I2C_SPEED_FM 1 /* fast mode (400Kb/s) */
57 #define I2C_SPEED_FMPLUS 2 /* fast mode+ (1Mb/s) */
58 #define I2C_SPEED_HS 3 /* high speed (3.4Mb/s) */
59
60 /* i2c bus instance properties */
61 #define I2C_PROP_INDIRECT_PROBE_STRATEGY \
62 "i2c-indirect-probe-strategy"
63 #define I2C_PROBE_STRATEGY_QUICK_WRITE \
64 "smbus-quick-write"
65 #define I2C_PROBE_STRATEGY_RECEIVE_BYTE \
66 "smbus-receive-byte"
67 #define I2C_PROBE_STRATEGY_NONE \
68 "none"
69
70 #define I2C_PROP_INDIRECT_DEVICE_PERMITLIST \
71 "i2c-indirect-device-permitlist"
72 /* value is a prop_array of prop_strings */
73
74 struct ic_intr_list {
75 LIST_ENTRY(ic_intr_list) il_next;
76 int (*il_intr)(void *);
77 void *il_intrarg;
78 };
79
80 /*
81 * This structure provides the interface between the i2c framework
82 * and the underlying i2c controller.
83 *
84 * Note that this structure is designed specifically to allow us
85 * to either use the autoconfiguration framework or not. This
86 * allows a driver for a board with a private i2c bus use generic
87 * i2c client drivers for chips that might be on that board.
88 */
89 typedef struct i2c_controller {
90 void *ic_cookie; /* controller private */
91
92 /*
93 * These provide synchronization in the presence of
94 * multiple users of the i2c bus. When a device
95 * driver wishes to perform transfers on the i2c
96 * bus, the driver should acquire the bus. When
97 * the driver is finished, it should release the
98 * bus.
99 *
100 * The main synchronization logic is handled by the
101 * generic i2c layer, but optional hooks to back-end
102 * drivers are provided in case additional processing
103 * is needed (e.g. enabling the i2c controller).
104 */
105 kmutex_t ic_bus_lock;
106 int (*ic_acquire_bus)(void *, int);
107 void (*ic_release_bus)(void *, int);
108
109 /*
110 * The preferred API for clients of the i2c interface
111 * is the scripted API. This handles i2c controllers
112 * that do not provide raw access to the i2c signals.
113 */
114 int (*ic_exec)(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
115 void *, size_t, int);
116
117 int (*ic_send_start)(void *, int);
118 int (*ic_send_stop)(void *, int);
119 int (*ic_initiate_xfer)(void *, i2c_addr_t, int);
120 int (*ic_read_byte)(void *, uint8_t *, int);
121 int (*ic_write_byte)(void *, uint8_t, int);
122
123 struct i2c_tag_private *ic_tag_private;
124 } *i2c_tag_t;
125
126 /* Used to attach the i2c framework to the controller. */
127 struct i2cbus_attach_args {
128 i2c_tag_t iba_tag; /* the controller */
129 prop_array_t iba_child_devices; /* child devices (direct config) */
130 };
131
132 /* Type of value stored in "ia_cookie" */
133 enum i2c_cookie_type {
134 I2C_COOKIE_NONE, /* Cookie is not valid */
135 I2C_COOKIE_OF, /* Cookie is an OF node phandle */
136 I2C_COOKIE_ACPI, /* Cookie is an ACPI handle */
137 };
138
139 /* Used to attach devices on the i2c bus. */
140 struct i2c_attach_args {
141 i2c_tag_t ia_tag; /* our controller */
142 i2c_addr_t ia_addr; /* address of device */
143 int ia_type; /* bus type */
144 /* only set if using direct config */
145 const char * ia_name; /* name of the device */
146 int ia_ncompat; /* number of pointers in the
147 ia_compat array */
148 const char ** ia_compat; /* chip names */
149 prop_dictionary_t ia_prop; /* dictionary for this device */
150 /*
151 * The following is of limited usefulness and should only be used
152 * in rare cases where we really know what we are doing. Example:
153 * a machine dependent i2c driver (located in sys/arch/$arch/dev)
154 * needing to access some firmware properties.
155 * Depending on the firmware in use, an identifier for the device
156 * may be present. Example: on OpenFirmware machines the device
157 * tree OF node - if available. This info is hard to transport
158 * down to MD drivers through the MI i2c bus otherwise.
159 *
160 * On ACPI platforms this is the ACPI_HANDLE of the device.
161 */
162 uintptr_t ia_cookie; /* OF node in openfirmware machines */
163 enum i2c_cookie_type ia_cookietype; /* Value type of cookie */
164 };
165
166 /*
167 * API presented to i2c controllers.
168 */
169 int iicbus_print(void *, const char *);
170 void iic_tag_init(i2c_tag_t);
171 void iic_tag_fini(i2c_tag_t);
172
173 /*
174 * API presented to i2c devices.
175 */
176 int iic_compatible_match(const struct i2c_attach_args *,
177 const struct device_compatible_entry *);
178 bool iic_use_direct_match(const struct i2c_attach_args *, const cfdata_t,
179 const struct device_compatible_entry *, int *);
180 const struct device_compatible_entry *
181 iic_compatible_lookup(const struct i2c_attach_args *,
182 const struct device_compatible_entry *);
183
184 /*
185 * Constants to indicate the quality of a match made by a driver's
186 * match routine, from lowest to highest:
187 *
188 * -- Address only; no other checks were made.
189 *
190 * -- Address + device probed and recognized.
191 *
192 * -- Direct-config match by "compatible" string.
193 *
194 * -- Direct-config match by specific driver name.
195 */
196 #define I2C_MATCH_ADDRESS_ONLY 1
197 #define I2C_MATCH_ADDRESS_AND_PROBE 2
198 #define I2C_MATCH_DIRECT_COMPATIBLE 10
199 #define I2C_MATCH_DIRECT_COMPATIBLE_MAX 99
200 #define I2C_MATCH_DIRECT_SPECIFIC 100
201
202 #ifdef _I2C_PRIVATE
203 /*
204 * Macros used internally by the i2c framework.
205 */
206 #define iic_send_start(ic, flags) \
207 (*(ic)->ic_send_start)((ic)->ic_cookie, (flags))
208 #define iic_send_stop(ic, flags) \
209 (*(ic)->ic_send_stop)((ic)->ic_cookie, (flags))
210 #define iic_initiate_xfer(ic, addr, flags) \
211 (*(ic)->ic_initiate_xfer)((ic)->ic_cookie, (addr), (flags))
212
213 #define iic_read_byte(ic, bytep, flags) \
214 (*(ic)->ic_read_byte)((ic)->ic_cookie, (bytep), (flags))
215 #define iic_write_byte(ic, byte, flags) \
216 (*(ic)->ic_write_byte)((ic)->ic_cookie, (byte), (flags))
217 #endif /* _I2C_PRIVATE */
218
219 /*
220 * Simplified API for clients of the i2c framework. Definitions
221 * in <dev/i2c/i2c_io.h>.
222 */
223 int iic_acquire_bus(i2c_tag_t, int);
224 void iic_release_bus(i2c_tag_t, int);
225 int iic_exec(i2c_tag_t, i2c_op_t, i2c_addr_t, const void *,
226 size_t, void *, size_t, int);
227
228 int iic_smbus_write_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t, int);
229 int iic_smbus_write_word(i2c_tag_t, i2c_addr_t, uint8_t, uint16_t, int);
230 int iic_smbus_read_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, int);
231 int iic_smbus_read_word(i2c_tag_t, i2c_addr_t, uint8_t, uint16_t *, int);
232 int iic_smbus_receive_byte(i2c_tag_t, i2c_addr_t, uint8_t *, int);
233 int iic_smbus_send_byte(i2c_tag_t, i2c_addr_t, uint8_t, int);
234 int iic_smbus_quick_read(i2c_tag_t, i2c_addr_t, int);
235 int iic_smbus_quick_write(i2c_tag_t, i2c_addr_t, int);
236 int iic_smbus_block_read(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *,
237 size_t, int);
238 int iic_smbus_block_write(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *,
239 size_t, int);
240
241 #endif /* _DEV_I2C_I2CVAR_H_ */
242