linux_i2c.c revision 1.2.10.3
1 1.2.10.2 tls /* $NetBSD: linux_i2c.c,v 1.2.10.3 2017/12/03 11:38:00 jdolecek Exp $ */ 2 1.2.10.2 tls 3 1.2.10.2 tls /*- 4 1.2.10.3 jdolecek * Copyright (c) 2015 The NetBSD Foundation, Inc. 5 1.2.10.2 tls * All rights reserved. 6 1.2.10.2 tls * 7 1.2.10.2 tls * This code is derived from software contributed to The NetBSD Foundation 8 1.2.10.2 tls * by Taylor R. Campbell. 9 1.2.10.2 tls * 10 1.2.10.2 tls * Redistribution and use in source and binary forms, with or without 11 1.2.10.2 tls * modification, are permitted provided that the following conditions 12 1.2.10.2 tls * are met: 13 1.2.10.2 tls * 1. Redistributions of source code must retain the above copyright 14 1.2.10.2 tls * notice, this list of conditions and the following disclaimer. 15 1.2.10.2 tls * 2. Redistributions in binary form must reproduce the above copyright 16 1.2.10.2 tls * notice, this list of conditions and the following disclaimer in the 17 1.2.10.2 tls * documentation and/or other materials provided with the distribution. 18 1.2.10.2 tls * 19 1.2.10.2 tls * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 1.2.10.2 tls * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 1.2.10.2 tls * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 1.2.10.2 tls * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 1.2.10.2 tls * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 1.2.10.2 tls * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 1.2.10.2 tls * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 1.2.10.2 tls * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 1.2.10.2 tls * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 1.2.10.2 tls * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 1.2.10.2 tls * POSSIBILITY OF SUCH DAMAGE. 30 1.2.10.2 tls */ 31 1.2.10.2 tls 32 1.2.10.2 tls #include <sys/cdefs.h> 33 1.2.10.2 tls __KERNEL_RCSID(0, "$NetBSD: linux_i2c.c,v 1.2.10.3 2017/12/03 11:38:00 jdolecek Exp $"); 34 1.2.10.2 tls 35 1.2.10.2 tls #include <sys/types.h> 36 1.2.10.2 tls #include <sys/errno.h> 37 1.2.10.3 jdolecek #include <sys/kmem.h> 38 1.2.10.2 tls #include <sys/queue.h> /* XXX include order botch: i2cvar.h needs */ 39 1.2.10.2 tls 40 1.2.10.2 tls #include <dev/i2c/i2cvar.h> 41 1.2.10.2 tls #include <dev/i2c/i2c_bitbang.h> /* XXX include order botch */ 42 1.2.10.2 tls 43 1.2.10.2 tls #include <linux/i2c.h> 44 1.2.10.2 tls #include <linux/i2c-algo-bit.h> 45 1.2.10.2 tls 46 1.2.10.2 tls static int netbsd_i2c_transfer(i2c_tag_t, struct i2c_msg *, int); 47 1.2.10.2 tls static i2c_op_t linux_i2c_flags_op(uint16_t, bool); 48 1.2.10.2 tls static int linux_i2c_flags_flags(uint16_t); 49 1.2.10.2 tls static uint32_t linux_i2cbb_functionality(struct i2c_adapter *); 50 1.2.10.2 tls static int linux_i2cbb_xfer(struct i2c_adapter *, struct i2c_msg *, int); 51 1.2.10.2 tls static void linux_i2cbb_set_bits(void *, uint32_t); 52 1.2.10.2 tls static uint32_t linux_i2cbb_read_bits(void *); 53 1.2.10.2 tls static void linux_i2cbb_set_dir(void *, uint32_t); 54 1.2.10.2 tls static int linux_i2cbb_send_start(void *, int); 55 1.2.10.2 tls static int linux_i2cbb_send_stop(void *, int); 56 1.2.10.2 tls static int linux_i2cbb_initiate_xfer(void *, i2c_addr_t, int); 57 1.2.10.2 tls static int linux_i2cbb_read_byte(void *, uint8_t *, int); 58 1.2.10.2 tls static int linux_i2cbb_write_byte(void *, uint8_t, int); 59 1.2.10.2 tls 60 1.2.10.3 jdolecek /* 62 1.2.10.3 jdolecek * Client operations: operations with a particular i2c slave device. 63 1.2.10.3 jdolecek */ 64 1.2.10.3 jdolecek 65 1.2.10.3 jdolecek struct i2c_client * 66 1.2.10.3 jdolecek i2c_new_device(struct i2c_adapter *adapter, const struct i2c_board_info *info) 67 1.2.10.3 jdolecek { 68 1.2.10.3 jdolecek struct i2c_client *client; 69 1.2.10.3 jdolecek 70 1.2.10.3 jdolecek client = kmem_alloc(sizeof(*client), KM_SLEEP); 71 1.2.10.3 jdolecek client->adapter = adapter; 72 1.2.10.3 jdolecek client->addr = info->addr; 73 1.2.10.3 jdolecek client->flags = info->flags; 74 1.2.10.3 jdolecek 75 1.2.10.3 jdolecek return client; 76 1.2.10.3 jdolecek } 77 1.2.10.3 jdolecek 78 1.2.10.3 jdolecek void 79 1.2.10.3 jdolecek i2c_unregister_device(struct i2c_client *client) 80 1.2.10.3 jdolecek { 81 1.2.10.3 jdolecek 82 1.2.10.3 jdolecek kmem_free(client, sizeof(*client)); 83 1.2.10.3 jdolecek } 84 1.2.10.3 jdolecek 85 1.2.10.3 jdolecek int 86 1.2.10.3 jdolecek i2c_master_send(const struct i2c_client *client, const char *buf, int count) 87 1.2.10.3 jdolecek { 88 1.2.10.3 jdolecek struct i2c_msg msg = { 89 1.2.10.3 jdolecek .addr = client->addr, 90 1.2.10.3 jdolecek .flags = client->flags & I2C_M_TEN, 91 1.2.10.3 jdolecek .len = count, 92 1.2.10.3 jdolecek .buf = __UNCONST(buf), 93 1.2.10.3 jdolecek }; 94 1.2.10.3 jdolecek int ret; 95 1.2.10.3 jdolecek 96 1.2.10.3 jdolecek KASSERT(0 <= count); 97 1.2.10.3 jdolecek 98 1.2.10.3 jdolecek ret = i2c_transfer(client->adapter, &msg, 1); 99 1.2.10.3 jdolecek if (ret <= 0) 100 1.2.10.3 jdolecek return ret; 101 1.2.10.3 jdolecek 102 1.2.10.3 jdolecek return count; 103 1.2.10.3 jdolecek } 104 1.2.10.3 jdolecek 105 1.2.10.3 jdolecek int 106 1.2.10.3 jdolecek i2c_master_recv(const struct i2c_client *client, char *buf, int count) 107 1.2.10.3 jdolecek { 108 1.2.10.3 jdolecek struct i2c_msg msg = { 109 1.2.10.3 jdolecek .addr = client->addr, 110 1.2.10.3 jdolecek .flags = (client->flags & I2C_M_TEN) | I2C_M_RD, 111 1.2.10.3 jdolecek .len = count, 112 1.2.10.3 jdolecek .buf = buf, 113 1.2.10.3 jdolecek }; 114 1.2.10.3 jdolecek int ret; 115 1.2.10.3 jdolecek 116 1.2.10.3 jdolecek ret = i2c_transfer(client->adapter, &msg, 1); 117 1.2.10.3 jdolecek if (ret <= 0) 118 1.2.10.3 jdolecek return ret; 119 1.2.10.3 jdolecek 120 1.2.10.3 jdolecek return count; 121 1.2.10.3 jdolecek } 122 1.2.10.3 jdolecek 123 1.2.10.3 jdolecek /* 125 1.2.10.3 jdolecek * Adapter operations: operations over an i2c bus via a particular 126 1.2.10.3 jdolecek * controller. 127 1.2.10.2 tls */ 128 1.2.10.2 tls 129 1.2.10.2 tls int 130 1.2.10.2 tls i2c_transfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int n) 131 1.2.10.2 tls { 132 1.2.10.2 tls 133 1.2.10.2 tls return (*adapter->algo->master_xfer)(adapter, msgs, n); 134 1.2.10.2 tls } 135 1.2.10.2 tls 136 1.2.10.2 tls static int 137 1.2.10.2 tls netbsd_i2c_transfer(i2c_tag_t i2c, struct i2c_msg *msgs, int n) 138 1.2.10.2 tls { 139 1.2.10.2 tls int i; 140 1.2.10.2 tls int error; 141 1.2.10.2 tls 142 1.2.10.2 tls for (i = 0; i < n; i++) { 143 1.2.10.2 tls const i2c_op_t op = linux_i2c_flags_op(msgs[i].flags, 144 1.2.10.2 tls ((i + 1) == n)); 145 1.2.10.2 tls const int flags = linux_i2c_flags_flags(msgs[i].flags); 146 1.2.10.2 tls 147 1.2.10.2 tls switch (op) { 148 1.2.10.2 tls case I2C_OP_READ: 149 1.2.10.2 tls case I2C_OP_READ_WITH_STOP: 150 1.2.10.2 tls error = iic_exec(i2c, op, msgs[i].addr, 151 1.2.10.2 tls NULL, 0, msgs[i].buf, msgs[i].len, flags); 152 1.2.10.2 tls break; 153 1.2.10.2 tls 154 1.2.10.2 tls case I2C_OP_WRITE: 155 1.2.10.2 tls case I2C_OP_WRITE_WITH_STOP: 156 1.2.10.2 tls error = iic_exec(i2c, op, msgs[i].addr, 157 1.2.10.2 tls msgs[i].buf, msgs[i].len, NULL, 0, flags); 158 1.2.10.2 tls break; 159 1.2.10.2 tls 160 1.2.10.2 tls default: 161 1.2.10.2 tls error = EINVAL; 162 1.2.10.2 tls } 163 1.2.10.2 tls 164 1.2.10.2 tls if (error) 165 1.2.10.2 tls /* XXX errno NetBSD->Linux */ 166 1.2.10.2 tls return -error; 167 1.2.10.2 tls } 168 1.2.10.2 tls 169 1.2.10.2 tls return n; 170 1.2.10.2 tls } 171 1.2.10.2 tls 172 1.2.10.2 tls static i2c_op_t 173 1.2.10.2 tls linux_i2c_flags_op(uint16_t flags, bool stop) 174 1.2.10.2 tls { 175 1.2.10.2 tls 176 1.2.10.2 tls if (ISSET(flags, I2C_M_RD)) 177 1.2.10.2 tls return (stop? I2C_OP_READ_WITH_STOP : I2C_OP_READ); 178 1.2.10.2 tls else 179 1.2.10.2 tls return (stop? I2C_OP_WRITE_WITH_STOP : I2C_OP_WRITE); 180 1.2.10.2 tls } 181 1.2.10.2 tls 182 1.2.10.2 tls static int 183 1.2.10.2 tls linux_i2c_flags_flags(uint16_t flags __unused) 184 1.2.10.2 tls { 185 1.2.10.2 tls 186 1.2.10.2 tls return 0; 187 1.2.10.3 jdolecek } 188 1.2.10.3 jdolecek 189 1.2.10.2 tls /* Bit-banging */ 191 1.2.10.2 tls 192 1.2.10.2 tls const struct i2c_algorithm i2c_bit_algo = { 193 1.2.10.2 tls .master_xfer = linux_i2cbb_xfer, 194 1.2.10.2 tls .functionality = linux_i2cbb_functionality, 195 1.2.10.2 tls }; 196 1.2.10.2 tls 197 1.2.10.2 tls static uint32_t 198 1.2.10.2 tls linux_i2cbb_functionality(struct i2c_adapter *adapter __unused) 199 1.2.10.2 tls { 200 1.2.10.2 tls uint32_t functions = 0; 201 1.2.10.2 tls 202 1.2.10.2 tls functions |= I2C_FUNC_I2C; 203 1.2.10.2 tls functions |= I2C_FUNC_NOSTART; 204 1.2.10.2 tls functions |= I2C_FUNC_SMBUS_EMUL; 205 1.2.10.2 tls functions |= I2C_FUNC_SMBUS_READ_BLOCK_DATA; 206 1.2.10.2 tls functions |= I2C_FUNC_SMBUS_BLOCK_PROC_CALL; 207 1.2.10.2 tls #if 0 208 1.2.10.2 tls functions |= I2C_FUNC_10BIT_ADDR; 209 1.2.10.2 tls functions |= I2C_FUNC_PROTOCOL_MANGLING; 210 1.2.10.2 tls #endif 211 1.2.10.2 tls 212 1.2.10.2 tls return functions; 213 1.2.10.2 tls } 214 1.2.10.2 tls 215 1.2.10.2 tls static int 216 1.2.10.2 tls linux_i2cbb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int n) 217 1.2.10.2 tls { 218 1.2.10.2 tls struct i2c_algo_bit_data *const abd = adapter->algo_data; 219 1.2.10.2 tls struct i2c_controller controller = { 220 1.2.10.2 tls .ic_cookie = abd, 221 1.2.10.2 tls .ic_send_start = linux_i2cbb_send_start, 222 1.2.10.2 tls .ic_send_stop = linux_i2cbb_send_stop, 223 1.2.10.2 tls .ic_initiate_xfer = linux_i2cbb_initiate_xfer, 224 1.2.10.2 tls .ic_read_byte = linux_i2cbb_read_byte, 225 1.2.10.2 tls .ic_write_byte = linux_i2cbb_write_byte, 226 1.2.10.2 tls }; 227 1.2.10.2 tls i2c_tag_t i2c = &controller; 228 1.2.10.2 tls int error; 229 1.2.10.2 tls 230 1.2.10.2 tls if (abd->pre_xfer) { 231 1.2.10.2 tls error = (*abd->pre_xfer)(adapter); 232 1.2.10.2 tls if (error) 233 1.2.10.2 tls return error; 234 1.2.10.2 tls } 235 1.2.10.2 tls 236 1.2.10.2 tls error = netbsd_i2c_transfer(i2c, msgs, n); 237 1.2.10.2 tls 238 1.2.10.2 tls if (abd->post_xfer) 239 1.2.10.2 tls (*abd->post_xfer)(adapter); 240 1.2.10.2 tls 241 1.2.10.2 tls return error; 242 1.2.10.2 tls } 243 1.2.10.2 tls 244 1.2.10.2 tls #define LI2CBB_SDA 0x01 246 1.2.10.2 tls #define LI2CBB_SCL 0x02 247 1.2.10.2 tls #define LI2CBB_INPUT 0x04 248 1.2.10.2 tls #define LI2CBB_OUTPUT 0x08 249 1.2.10.2 tls 250 1.2.10.2 tls static struct i2c_bitbang_ops linux_i2cbb_ops = { 251 1.2.10.2 tls .ibo_set_bits = linux_i2cbb_set_bits, 252 1.2.10.2 tls .ibo_set_dir = linux_i2cbb_set_dir, 253 1.2.10.2 tls .ibo_read_bits = linux_i2cbb_read_bits, 254 1.2.10.2 tls .ibo_bits = { 255 1.2.10.2 tls [I2C_BIT_SDA] = LI2CBB_SDA, 256 1.2.10.2 tls [I2C_BIT_SCL] = LI2CBB_SCL, 257 1.2.10.2 tls [I2C_BIT_INPUT] = LI2CBB_INPUT, 258 1.2.10.2 tls [I2C_BIT_OUTPUT] = LI2CBB_OUTPUT, 259 1.2.10.2 tls }, 260 1.2.10.2 tls }; 261 1.2.10.2 tls 262 1.2.10.2 tls static void 263 1.2.10.2 tls linux_i2cbb_set_bits(void *cookie, uint32_t bits) 264 1.2.10.2 tls { 265 1.2.10.2 tls struct i2c_algo_bit_data *const abd = cookie; 266 1.2.10.2 tls 267 1.2.10.2 tls (*abd->setsda)(abd->data, (ISSET(bits, LI2CBB_SDA)? 1 : 0)); 268 1.2.10.2 tls (*abd->setscl)(abd->data, (ISSET(bits, LI2CBB_SCL)? 1 : 0)); 269 1.2.10.2 tls } 270 1.2.10.2 tls 271 1.2.10.2 tls static uint32_t 272 1.2.10.2 tls linux_i2cbb_read_bits(void *cookie) 273 1.2.10.2 tls { 274 1.2.10.2 tls struct i2c_algo_bit_data *const abd = cookie; 275 1.2.10.2 tls uint32_t bits = 0; 276 1.2.10.2 tls 277 1.2.10.2 tls if ((*abd->getsda)(abd->data)) 278 1.2.10.2 tls bits |= LI2CBB_SDA; 279 1.2.10.2 tls if ((*abd->getscl)(abd->data)) 280 1.2.10.2 tls bits |= LI2CBB_SCL; 281 1.2.10.2 tls 282 1.2.10.2 tls return bits; 283 1.2.10.2 tls } 284 1.2.10.2 tls 285 1.2.10.2 tls static void 286 1.2.10.2 tls linux_i2cbb_set_dir(void *cookie __unused, uint32_t bits __unused) 287 1.2.10.2 tls { 288 1.2.10.2 tls /* Linux doesn't do anything here... */ 289 1.2.10.2 tls } 290 1.2.10.2 tls 291 1.2.10.2 tls static int 293 1.2.10.2 tls linux_i2cbb_send_start(void *cookie, int flags) 294 1.2.10.2 tls { 295 1.2.10.2 tls 296 1.2.10.2 tls return i2c_bitbang_send_start(cookie, flags, &linux_i2cbb_ops); 297 1.2.10.2 tls } 298 1.2.10.2 tls 299 1.2.10.2 tls static int 300 1.2.10.2 tls linux_i2cbb_send_stop(void *cookie, int flags) 301 1.2.10.2 tls { 302 1.2.10.2 tls 303 1.2.10.2 tls return i2c_bitbang_send_stop(cookie, flags, &linux_i2cbb_ops); 304 1.2.10.2 tls } 305 1.2.10.2 tls 306 1.2.10.2 tls static int 307 1.2.10.2 tls linux_i2cbb_initiate_xfer(void *cookie, i2c_addr_t addr, int flags) 308 1.2.10.2 tls { 309 1.2.10.2 tls 310 1.2.10.2 tls return i2c_bitbang_initiate_xfer(cookie, addr, flags, 311 1.2.10.2 tls &linux_i2cbb_ops); 312 1.2.10.2 tls } 313 1.2.10.2 tls 314 1.2.10.2 tls static int 315 1.2.10.2 tls linux_i2cbb_read_byte(void *cookie, uint8_t *bytep, int flags) 316 1.2.10.2 tls { 317 1.2.10.2 tls 318 1.2.10.2 tls return i2c_bitbang_read_byte(cookie, bytep, flags, &linux_i2cbb_ops); 319 1.2.10.2 tls } 320 1.2.10.2 tls 321 1.2.10.2 tls static int 322 linux_i2cbb_write_byte(void *cookie, uint8_t byte, int flags) 323 { 324 325 return i2c_bitbang_write_byte(cookie, byte, flags, &linux_i2cbb_ops); 326 } 327
Indexes created Tue Sep 30 20:09:53 GMT 2025