1 /* $NetBSD: i2cvar.h,v 1.31 2025/09/20 21:24:29 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 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 }; 130 131 /* Type of value stored in "ia_cookie" */ 132 enum i2c_cookie_type { 133 I2C_COOKIE_NONE, /* Cookie is not valid */ 134 I2C_COOKIE_OF, /* Cookie is an OF node phandle */ 135 I2C_COOKIE_ACPI, /* Cookie is an ACPI handle */ 136 }; 137 138 /* Used to attach devices on the i2c bus. */ 139 struct i2c_attach_args { 140 i2c_tag_t ia_tag; /* our controller */ 141 i2c_addr_t ia_addr; /* address of device */ 142 int ia_type; /* bus type */ 143 /* only set if using direct config */ 144 const char * ia_name; /* name of the device */ 145 int ia_ncompat; /* number of pointers in the 146 ia_compat array */ 147 const char ** ia_compat; /* chip names */ 148 prop_dictionary_t ia_prop; /* dictionary for this device */ 149 /* 150 * XXX These fields are deprecated; all of the necessary information 151 * XXX is available in the device's devhandle. The remain for 152 * XXX ABI compatbility until other changes requring an ABI version 153 * XXX bump are performed. 154 * 155 * The following is of limited usefulness and should only be used 156 * in rare cases where we really know what we are doing. Example: 157 * a machine dependent i2c driver (located in sys/arch/$arch/dev) 158 * needing to access some firmware properties. 159 * Depending on the firmware in use, an identifier for the device 160 * may be present. Example: on OpenFirmware machines the device 161 * tree OF node - if available. This info is hard to transport 162 * down to MD drivers through the MI i2c bus otherwise. 163 * 164 * On ACPI platforms this is the ACPI_HANDLE of the device. 165 */ 166 uintptr_t __xxx_ia_cookie; 167 enum i2c_cookie_type __xxx_ia_cookietype; 168 }; 169 170 /* 171 * API presented to i2c controllers. 172 */ 173 int iicbus_print(void *, const char *); 174 void iic_tag_init(i2c_tag_t); 175 void iic_tag_fini(i2c_tag_t); 176 177 int iic_acquire_bus_lock(kmutex_t *, int); 178 void iic_release_bus_lock(kmutex_t *); 179 180 static inline device_t 181 iicbus_attach_with_devhandle(device_t dev, i2c_tag_t tag, devhandle_t devhandle) 182 { 183 struct i2cbus_attach_args iba = { 184 .iba_tag = tag, 185 }; 186 return config_found(dev, &iba, iicbus_print, 187 CFARGS(.iattr = "i2cbus", 188 .devhandle = devhandle)); 189 } 190 191 static inline device_t 192 iicbus_attach(device_t dev, i2c_tag_t tag) 193 { 194 return iicbus_attach_with_devhandle(dev, tag, device_handle(dev)); 195 } 196 197 /* 198 * API presented to i2c devices. 199 */ 200 int iic_compatible_match(const struct i2c_attach_args *, 201 const struct device_compatible_entry *); 202 bool iic_use_direct_match(const struct i2c_attach_args *, const cfdata_t, 203 const struct device_compatible_entry *, int *); 204 const struct device_compatible_entry * 205 iic_compatible_lookup(const struct i2c_attach_args *, 206 const struct device_compatible_entry *); 207 208 /* 209 * Constants to indicate the quality of a match made by a driver's 210 * match routine, from lowest to highest: 211 * 212 * -- Address only; no other checks were made. 213 * 214 * -- Address + device probed and recognized. 215 * 216 * -- Direct-config match by "compatible" string. 217 * 218 * -- Direct-config match by specific driver name. 219 */ 220 #define I2C_MATCH_ADDRESS_ONLY 1 221 #define I2C_MATCH_ADDRESS_AND_PROBE 2 222 #define I2C_MATCH_DIRECT_COMPATIBLE 10 223 #define I2C_MATCH_DIRECT_COMPATIBLE_MAX 99 224 #define I2C_MATCH_DIRECT_SPECIFIC 100 225 226 #ifdef _I2C_PRIVATE 227 /* 228 * Macros used internally by the i2c framework. 229 */ 230 #define iic_send_start(ic, flags) \ 231 (*(ic)->ic_send_start)((ic)->ic_cookie, (flags)) 232 #define iic_send_stop(ic, flags) \ 233 (*(ic)->ic_send_stop)((ic)->ic_cookie, (flags)) 234 #define iic_initiate_xfer(ic, addr, flags) \ 235 (*(ic)->ic_initiate_xfer)((ic)->ic_cookie, (addr), (flags)) 236 237 #define iic_read_byte(ic, bytep, flags) \ 238 (*(ic)->ic_read_byte)((ic)->ic_cookie, (bytep), (flags)) 239 #define iic_write_byte(ic, byte, flags) \ 240 (*(ic)->ic_write_byte)((ic)->ic_cookie, (byte), (flags)) 241 #endif /* _I2C_PRIVATE */ 242 243 /* 244 * Simplified API for clients of the i2c framework. Definitions 245 * in <dev/i2c/i2c_io.h>. 246 */ 247 int iic_acquire_bus(i2c_tag_t, int); 248 void iic_release_bus(i2c_tag_t, int); 249 int iic_exec(i2c_tag_t, i2c_op_t, i2c_addr_t, const void *, 250 size_t, void *, size_t, int); 251 252 int iic_smbus_write_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t, int); 253 int iic_smbus_write_word(i2c_tag_t, i2c_addr_t, uint8_t, uint16_t, int); 254 int iic_smbus_read_byte(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, int); 255 int iic_smbus_read_word(i2c_tag_t, i2c_addr_t, uint8_t, uint16_t *, int); 256 int iic_smbus_receive_byte(i2c_tag_t, i2c_addr_t, uint8_t *, int); 257 int iic_smbus_send_byte(i2c_tag_t, i2c_addr_t, uint8_t, int); 258 int iic_smbus_quick_read(i2c_tag_t, i2c_addr_t, int); 259 int iic_smbus_quick_write(i2c_tag_t, i2c_addr_t, int); 260 int iic_smbus_block_read(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, 261 size_t, int); 262 int iic_smbus_block_write(i2c_tag_t, i2c_addr_t, uint8_t, uint8_t *, 263 size_t, int); 264 265 #endif /* _DEV_I2C_I2CVAR_H_ */ 266