1 1.1 brad 2 1.3 thorpej /* $NetBSD: scmdi2c.c,v 1.3 2025/09/12 13:48:26 thorpej Exp $ */ 3 1.1 brad 4 1.1 brad /* 5 1.1 brad * Copyright (c) 2021 Brad Spencer <brad (at) anduin.eldar.org> 6 1.1 brad * 7 1.1 brad * Permission to use, copy, modify, and distribute this software for any 8 1.1 brad * purpose with or without fee is hereby granted, provided that the above 9 1.1 brad * copyright notice and this permission notice appear in all copies. 10 1.1 brad * 11 1.1 brad * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 1.1 brad * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 1.1 brad * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 1.1 brad * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 1.1 brad * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 1.1 brad * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 1.1 brad * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 1.1 brad */ 19 1.1 brad 20 1.1 brad #include <sys/cdefs.h> 21 1.3 thorpej __KERNEL_RCSID(0, "$NetBSD: scmdi2c.c,v 1.3 2025/09/12 13:48:26 thorpej Exp $"); 22 1.1 brad 23 1.1 brad /* 24 1.1 brad * I2C driver for the Sparkfun Serial motor controller. 25 1.1 brad * Uses the common code to do the actual work. 26 1.1 brad */ 27 1.1 brad 28 1.1 brad #include <sys/param.h> 29 1.1 brad #include <sys/systm.h> 30 1.1 brad #include <sys/kernel.h> 31 1.1 brad #include <sys/device.h> 32 1.1 brad #include <sys/module.h> 33 1.1 brad #include <sys/conf.h> 34 1.1 brad #include <sys/sysctl.h> 35 1.1 brad #include <sys/mutex.h> 36 1.1 brad #include <sys/condvar.h> 37 1.1 brad #include <sys/pool.h> 38 1.1 brad #include <sys/kmem.h> 39 1.1 brad 40 1.1 brad #include <dev/i2c/i2cvar.h> 41 1.1 brad #include <dev/spi/spivar.h> 42 1.1 brad #include <dev/ic/scmdreg.h> 43 1.1 brad #include <dev/ic/scmdvar.h> 44 1.1 brad 45 1.3 thorpej static const struct device_compatible_entry compat_data[] = { 46 1.3 thorpej { .compat = "sparkfun,scmd-motor-driver" }, 47 1.3 thorpej 48 1.3 thorpej DEVICE_COMPAT_EOL 49 1.3 thorpej }; 50 1.3 thorpej 51 1.1 brad extern struct cdevsw scmd_cdevsw; 52 1.1 brad 53 1.1 brad extern void scmd_attach(struct scmd_sc *); 54 1.1 brad 55 1.1 brad static int scmdi2c_poke(i2c_tag_t, i2c_addr_t, bool); 56 1.1 brad static int scmdi2c_match(device_t, cfdata_t, void *); 57 1.1 brad static void scmdi2c_attach(device_t, device_t, void *); 58 1.1 brad static int scmdi2c_detach(device_t, int); 59 1.1 brad static int scmdi2c_activate(device_t, enum devact); 60 1.1 brad 61 1.1 brad #define SCMD_DEBUG 62 1.1 brad #ifdef SCMD_DEBUG 63 1.1 brad #define DPRINTF(s, l, x) \ 64 1.1 brad do { \ 65 1.1 brad if (l <= s->sc_scmddebug) \ 66 1.1 brad printf x; \ 67 1.1 brad } while (/*CONSTCOND*/0) 68 1.1 brad #else 69 1.1 brad #define DPRINTF(s, l, x) 70 1.1 brad #endif 71 1.1 brad 72 1.1 brad CFATTACH_DECL_NEW(scmdi2c, sizeof(struct scmd_sc), 73 1.1 brad scmdi2c_match, scmdi2c_attach, scmdi2c_detach, scmdi2c_activate); 74 1.1 brad 75 1.1 brad static int 76 1.1 brad scmdi2c_read_reg_direct(i2c_tag_t tag, i2c_addr_t addr, uint8_t reg, 77 1.1 brad uint8_t *buf) 78 1.1 brad { 79 1.1 brad return iic_exec(tag, I2C_OP_READ_WITH_STOP, addr, ®, 1, buf, 80 1.1 brad 1, 0); 81 1.1 brad } 82 1.1 brad 83 1.1 brad static int 84 1.1 brad scmdi2c_read_reg(struct scmd_sc *sc, uint8_t reg, uint8_t *buf) 85 1.1 brad { 86 1.1 brad return scmdi2c_read_reg_direct(sc->sc_tag, sc->sc_addr, reg, buf); 87 1.1 brad } 88 1.1 brad 89 1.1 brad static int 90 1.1 brad scmdi2c_write_reg_direct(i2c_tag_t tag, i2c_addr_t addr, uint8_t reg, 91 1.1 brad uint8_t buf) 92 1.1 brad { 93 1.1 brad return iic_exec(tag, I2C_OP_WRITE_WITH_STOP, addr, ®, 1, &buf, 94 1.1 brad 1, 0); 95 1.1 brad } 96 1.1 brad 97 1.1 brad static int 98 1.1 brad scmdi2c_write_reg(struct scmd_sc *sc, uint8_t reg, uint8_t buf) 99 1.1 brad { 100 1.1 brad return scmdi2c_write_reg_direct(sc->sc_tag, sc->sc_addr, reg, buf); 101 1.1 brad } 102 1.1 brad 103 1.1 brad static int 104 1.1 brad scmdi2c_acquire_bus(struct scmd_sc *sc) 105 1.1 brad { 106 1.1 brad return(iic_acquire_bus(sc->sc_tag, 0)); 107 1.1 brad } 108 1.1 brad 109 1.1 brad static void 110 1.1 brad scmdi2c_release_bus(struct scmd_sc *sc) 111 1.1 brad { 112 1.1 brad iic_release_bus(sc->sc_tag, 0); 113 1.1 brad } 114 1.1 brad 115 1.1 brad static int 116 1.1 brad scmdi2c_poke(i2c_tag_t tag, i2c_addr_t addr, bool matchdebug) 117 1.1 brad { 118 1.1 brad uint8_t reg = SCMD_REG_ID; 119 1.1 brad uint8_t buf; 120 1.1 brad int error; 121 1.1 brad 122 1.1 brad error = scmdi2c_read_reg_direct(tag, addr, reg, &buf); 123 1.1 brad if (matchdebug) { 124 1.1 brad printf("poke X 1: %d %02x %d\n", addr, buf, error); 125 1.1 brad } 126 1.1 brad return error; 127 1.1 brad } 128 1.1 brad 129 1.1 brad static int 130 1.3 thorpej scmdi2c_match(device_t parent, cfdata_t cf, void *aux) 131 1.1 brad { 132 1.1 brad struct i2c_attach_args *ia = aux; 133 1.1 brad int error, match_result; 134 1.1 brad const bool matchdebug = false; 135 1.1 brad 136 1.3 thorpej if (iic_use_direct_match(ia, cf, compat_data, &match_result)) 137 1.1 brad return match_result; 138 1.1 brad 139 1.1 brad if (matchdebug) { 140 1.1 brad printf("Looking at ia_addr: %x\n",ia->ia_addr); 141 1.1 brad } 142 1.1 brad 143 1.1 brad /* indirect config - check for configured address */ 144 1.1 brad if (!(ia->ia_addr >= SCMD_LOW_I2C_ADDR && 145 1.1 brad ia->ia_addr <= SCMD_HIGH_I2C_ADDR)) 146 1.1 brad return 0; 147 1.1 brad 148 1.1 brad /* 149 1.1 brad * Check to see if something is really at this i2c address. 150 1.1 brad * This will keep phantom devices from appearing 151 1.1 brad */ 152 1.1 brad if (iic_acquire_bus(ia->ia_tag, 0) != 0) { 153 1.1 brad if (matchdebug) 154 1.1 brad printf("in match acquire bus failed\n"); 155 1.1 brad return 0; 156 1.1 brad } 157 1.1 brad 158 1.1 brad error = scmdi2c_poke(ia->ia_tag, ia->ia_addr, matchdebug); 159 1.1 brad iic_release_bus(ia->ia_tag, 0); 160 1.1 brad 161 1.1 brad return error == 0 ? I2C_MATCH_ADDRESS_AND_PROBE : 0; 162 1.1 brad } 163 1.1 brad 164 1.1 brad static void 165 1.1 brad scmdi2c_attach(device_t parent, device_t self, void *aux) 166 1.1 brad { 167 1.1 brad struct scmd_sc *sc; 168 1.1 brad struct i2c_attach_args *ia; 169 1.1 brad 170 1.1 brad ia = aux; 171 1.1 brad sc = device_private(self); 172 1.1 brad 173 1.1 brad sc->sc_dev = self; 174 1.1 brad sc->sc_tag = ia->ia_tag; 175 1.1 brad sc->sc_addr = ia->ia_addr; 176 1.1 brad sc->sc_scmddebug = 0; 177 1.1 brad sc->sc_topaddr = 0xff; 178 1.1 brad sc->sc_opened = false; 179 1.1 brad sc->sc_dying = false; 180 1.1 brad sc->sc_func_acquire_bus = &scmdi2c_acquire_bus; 181 1.1 brad sc->sc_func_release_bus = &scmdi2c_release_bus; 182 1.1 brad sc->sc_func_read_register = &scmdi2c_read_reg; 183 1.1 brad sc->sc_func_write_register = &scmdi2c_write_reg; 184 1.1 brad 185 1.1 brad mutex_init(&sc->sc_mutex, MUTEX_DEFAULT, IPL_NONE); 186 1.1 brad mutex_init(&sc->sc_condmutex, MUTEX_DEFAULT, IPL_NONE); 187 1.1 brad mutex_init(&sc->sc_dying_mutex, MUTEX_DEFAULT, IPL_NONE); 188 1.1 brad cv_init(&sc->sc_condvar, "scmdi2ccv"); 189 1.1 brad cv_init(&sc->sc_cond_dying, "scmdi2cdc"); 190 1.1 brad 191 1.1 brad scmd_attach(sc); 192 1.1 brad 193 1.1 brad return; 194 1.1 brad } 195 1.1 brad 196 1.1 brad static int 197 1.1 brad scmdi2c_detach(device_t self, int flags) 198 1.1 brad { 199 1.1 brad struct scmd_sc *sc; 200 1.1 brad 201 1.1 brad sc = device_private(self); 202 1.1 brad 203 1.1 brad mutex_enter(&sc->sc_mutex); 204 1.1 brad sc->sc_dying = true; 205 1.1 brad /* If this is true we are still open, destroy the condvar */ 206 1.1 brad if (sc->sc_opened) { 207 1.1 brad mutex_enter(&sc->sc_dying_mutex); 208 1.1 brad DPRINTF(sc, 2, ("%s: Will wait for anything to exit\n", 209 1.1 brad device_xname(sc->sc_dev))); 210 1.1 brad /* In the worst case this will time out after 5 seconds. 211 1.1 brad * It really should not take that long for the drain / whatever 212 1.1 brad * to happen 213 1.1 brad */ 214 1.1 brad cv_timedwait_sig(&sc->sc_cond_dying, 215 1.1 brad &sc->sc_dying_mutex, mstohz(5000)); 216 1.1 brad mutex_exit(&sc->sc_dying_mutex); 217 1.1 brad cv_destroy(&sc->sc_cond_dying); 218 1.1 brad } 219 1.1 brad cv_destroy(&sc->sc_condvar); 220 1.1 brad mutex_exit(&sc->sc_mutex); 221 1.1 brad 222 1.1 brad mutex_destroy(&sc->sc_mutex); 223 1.1 brad mutex_destroy(&sc->sc_condmutex); 224 1.1 brad 225 1.1 brad return 0; 226 1.1 brad } 227 1.1 brad 228 1.1 brad int 229 1.1 brad scmdi2c_activate(device_t self, enum devact act) 230 1.1 brad { 231 1.1 brad struct scmd_sc *sc = device_private(self); 232 1.1 brad 233 1.1 brad switch (act) { 234 1.1 brad case DVACT_DEACTIVATE: 235 1.1 brad sc->sc_dying = true; 236 1.1 brad return 0; 237 1.1 brad default: 238 1.1 brad return EOPNOTSUPP; 239 1.1 brad } 240 1.1 brad } 241 1.1 brad 242 1.2 pgoyette MODULE(MODULE_CLASS_DRIVER, scmdi2c, "iic,scmd"); 243 1.1 brad 244 1.1 brad #ifdef _MODULE 245 1.1 brad /* Like other drivers, we do this because the scmd common 246 1.1 brad * driver has the definitions already. 247 1.1 brad */ 248 1.1 brad #undef CFDRIVER_DECL 249 1.1 brad #define CFDRIVER_DECL(name, class, attr) 250 1.1 brad #include "ioconf.c" 251 1.1 brad #endif 252 1.1 brad 253 1.1 brad static int 254 1.1 brad scmdi2c_modcmd(modcmd_t cmd, void *opaque) 255 1.1 brad { 256 1.1 brad #ifdef _MODULE 257 1.1 brad int error = 0; 258 1.1 brad static struct cfdriver * const no_cfdriver_vec[] = { NULL }; 259 1.1 brad #endif 260 1.1 brad 261 1.1 brad switch (cmd) { 262 1.1 brad case MODULE_CMD_INIT: 263 1.1 brad #ifdef _MODULE 264 1.1 brad /* I really do not understand why I had to do this this way. 265 1.1 brad * If I did not then the module would either not install when 266 1.1 brad * the SPI driver and hence the scmd dependent driver was compiled 267 1.1 brad * into the kernel, or it would not install if it was not. 268 1.1 brad * I suspect something is still not set up correctly somewhere, but 269 1.1 brad * I am at a lose to see what. 270 1.1 brad * 271 1.1 brad * The first config_init_component will fail if the SPI driver and the 272 1.1 brad * scmd dependent is in the kernel already, but the second one will work. 273 1.1 brad * Otherwise the other way around. 274 1.1 brad * 275 1.1 brad * This all manages to get this module set up in any situation. 276 1.1 brad */ 277 1.1 brad error = config_init_component(cfdriver_ioconf_scmdi2c, 278 1.1 brad cfattach_ioconf_scmdi2c, cfdata_ioconf_scmdi2c); 279 1.1 brad if (error) { 280 1.1 brad aprint_error("%s: Trying no_cfdriver_vec method: %d\n", 281 1.1 brad scmd_cd.cd_name, error); 282 1.1 brad error = config_init_component(no_cfdriver_vec, 283 1.1 brad cfattach_ioconf_scmdi2c, cfdata_ioconf_scmdi2c); 284 1.1 brad } 285 1.1 brad 286 1.1 brad return error; 287 1.1 brad #else 288 1.1 brad return 0; 289 1.1 brad #endif 290 1.1 brad case MODULE_CMD_FINI: 291 1.1 brad #ifdef _MODULE 292 1.1 brad /* See above.. same thing */ 293 1.1 brad error = config_fini_component(cfdriver_ioconf_scmdi2c, 294 1.1 brad cfattach_ioconf_scmdi2c, cfdata_ioconf_scmdi2c); 295 1.1 brad if (error) { 296 1.1 brad aprint_error("%s: Trying no_cfdriver_vec method: %d\n", 297 1.1 brad scmd_cd.cd_name, error); 298 1.1 brad error = config_fini_component(no_cfdriver_vec, 299 1.1 brad cfattach_ioconf_scmdi2c, cfdata_ioconf_scmdi2c); 300 1.1 brad } 301 1.1 brad 302 1.1 brad return error; 303 1.1 brad #else 304 1.1 brad return 0; 305 1.1 brad #endif 306 1.1 brad default: 307 1.1 brad return ENOTTY; 308 1.1 brad } 309 1.1 brad } 310