i2cvar.h revision 1.32
1 /* $NetBSD: i2cvar.h,v 1.32 2025/09/21 14:43:19 thorpej 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 /* 75 * This structure provides the interface between the i2c framework 76 * and the underlying i2c controller. 77 * 78 * Note that this structure is designed specifically to allow us 79 * to either use the autoconfiguration framework or not. This 80 * allows a driver for a board with a private i2c bus use generic 81 * i2c client drivers for chips that might be on that board. 82 */ 83 typedef struct i2c_controller { 84 void *ic_cookie; /* controller private */ 85 86 /* 87 * Multi-channel i2c controllers and i2c muxes allow 88 * for multiple busses to be driven by a single block 89 * of controller logic. Each of these busses is 90 * represented by a logical controller with its own 91 * i2c_tag_t. By default, each i2c_tag_t is initialized 92 * indicating a single-bus controller, but multi-channel 93 * controllers and muxes should initialize this field to 94 * indicate which logical bus number this i2c_tag_t is 95 * associated with. 96 */ 97 int ic_channel; 98 99 /* 100 * These provide synchronization in the presence of 101 * multiple users of the i2c bus. When a device 102 * driver wishes to perform transfers on the i2c 103 * bus, the driver should acquire the bus. When 104 * the driver is finished, it should release the 105 * bus. 106 * 107 * The main synchronization logic is handled by the 108 * generic i2c layer, but optional hooks to back-end 109 * drivers are provided in case additional processing 110 * is needed (e.g. enabling the i2c controller). 111 */ 112 kmutex_t ic_bus_lock; 113 int (*ic_acquire_bus)(void *, int); 114 void (*ic_release_bus)(void *, int); 115 116 /* 117 * The preferred API for clients of the i2c interface 118 * is the scripted API. This handles i2c controllers 119 * that do not provide raw access to the i2c signals. 120 */ 121 int (*ic_exec)(void *, i2c_op_t, i2c_addr_t, const void *, size_t, 122 void *, size_t, int); 123 124 int (*ic_send_start)(void *, int); 125 int (*ic_send_stop)(void *, int); 126 int (*ic_initiate_xfer)(void *, i2c_addr_t, int); 127 int (*ic_read_byte)(void *, uint8_t *, int); 128 int (*ic_write_byte)(void *, uint8_t, int); 129 130 /* For future expansion; do not remove. */ 131 struct i2c_tag_private *ic_tag_private; 132 } *i2c_tag_t; 133 134 #define I2C_CHANNEL_DEFAULT -1 135 136 static inline int 137 i2c_tag_channel(i2c_tag_t tag) 138 { 139 return tag->ic_channel == I2C_CHANNEL_DEFAULT ? 0 140 : tag->ic_channel; 141 } 142 143 /* Used to attach the i2c framework to the controller. */ 144 struct i2cbus_attach_args { 145 i2c_tag_t iba_tag; /* the controller */ 146 }; 147 148 /* Used to attach devices on the i2c bus. */ 149 struct i2c_attach_args { 150 i2c_tag_t ia_tag; /* our controller */ 151 i2c_addr_t ia_addr; /* address of device */ 152 153 /* only set if using direct config */ 154 const char * ia_name; /* name of the device */ 155 const char * ia_clist; /* compatible strlist */ 156 size_t ia_clist_size; /* size of compatible strlist */ 157 devhandle_t ia_devhandle; /* device handle for the device */ 158 }; 159 160 /* 161 * API presented to i2c controllers. 162 */ 163 int iicbus_print(void *, const char *); 164 void iic_tag_init(i2c_tag_t); 165 void iic_tag_fini(i2c_tag_t); 166 167 int iic_acquire_bus_lock(kmutex_t *, int); 168 void iic_release_bus_lock(kmutex_t *); 169 170 static inline device_t 171 iicbus_attach_with_devhandle(device_t dev, i2c_tag_t tag, devhandle_t devhandle) 172 { 173 struct i2cbus_attach_args iba = { 174 .iba_tag = tag, 175 }; 176 return config_found(dev, &iba, iicbus_print, 177 CFARGS(.iattr = "i2cbus", 178 .devhandle = devhandle)); 179 } 180 181 static inline device_t 182 iicbus_attach(device_t dev, i2c_tag_t tag) 183 { 184 return iicbus_attach_with_devhandle(dev, tag, device_handle(dev)); 185 } 186 187 /* 188 * API presented to i2c devices. 189 */ 190 int iic_compatible_match(const struct i2c_attach_args *, 191 const struct device_compatible_entry *); 192 bool iic_use_direct_match(const struct i2c_attach_args *, const cfdata_t, 193 const struct device_compatible_entry *, int *); 194 const struct device_compatible_entry * 195 iic_compatible_lookup(const struct i2c_attach_args *, 196 const struct device_compatible_entry *); 197 198 /* 199 * Constants to indicate the quality of a match made by a driver's 200 * match routine, from lowest to highest: 201 * 202 * -- Address only; no other checks were made. 203 * 204 * -- Address + device probed and recognized. 205 * 206 * -- Direct-config match by "compatible" string. 207 * 208 * -- Direct-config match by specific driver name. 209 */ 210 #define I2C_MATCH_ADDRESS_ONLY 1 211 #define I2C_MATCH_ADDRESS_AND_PROBE 2 212 #define I2C_MATCH_DIRECT_COMPATIBLE 10 213 #define I2C_MATCH_DIRECT_COMPATIBLE_MAX 99 214 #define I2C_MATCH_DIRECT_SPECIFIC 100 215 216 #ifdef _I2C_PRIVATE 217 /* 218 * Macros used internally by the i2c framework. 219 */ 220 #define iic_send_start(ic, flags) \ 221 (*(ic)->ic_send_start)((ic)->ic_cookie, (flags)) 222 #define iic_send_stop(ic, flags) \ 223 (*(ic)->ic_send_stop)((ic)->ic_cookie, (flags)) 224 #define iic_initiate_xfer(ic, addr, flags) \ 225 (*(ic)->ic_initiate_xfer)((ic)->ic_cookie, (addr), (flags)) 226 227 #define iic_read_byte(ic, bytep, flags) \ 228 (*(ic)->ic_read_byte)((ic)->ic_cookie, (bytep), (flags)) 229 #define iic_write_byte(ic, byte, flags) \ 230 (*(ic)->ic_write_byte)((ic)->ic_cookie, (byte), (flags)) 231 #endif /* _I2C_PRIVATE */ 232 233 /* 234 * Simplified API for clients of the i2c framework. Definitions 235 * in <dev/i2c/i2c_io.h>. 236 */ 237 int iic_acquire_bus(i2c_tag_t, int); 238 void iic_release_bus(i2c_tag_t, int); 239 int iic_exec(i2c_tag_t, i2c_op_t, i2c_addr_t, const void *, 240 size_t, void *, size_t, int); 241 242 int iic_smbus_write_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t, int); 243 int iic_smbus_write_word(i2c_tag_t, i2c_addr_t, uint8_t, uint16_t, int); 244 int iic_smbus_read_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, int); 245 int iic_smbus_read_word(i2c_tag_t, i2c_addr_t, uint8_t, uint16_t *, int); 246 int iic_smbus_receive_byte(i2c_tag_t, i2c_addr_t, uint8_t *, int); 247 int iic_smbus_send_byte(i2c_tag_t, i2c_addr_t, uint8_t, int); 248 int iic_smbus_quick_read(i2c_tag_t, i2c_addr_t, int); 249 int iic_smbus_quick_write(i2c_tag_t, i2c_addr_t, int); 250 int iic_smbus_block_read(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, 251 size_t, int); 252 int iic_smbus_block_write(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, 253 size_t, int); 254 255 #endif /* _DEV_I2C_I2CVAR_H_ */ 256
Indexes created Tue Sep 23 14:10:03 GMT 2025