1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2001 Tsubai Masanari. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 * NetBSD: ki2c.c,v 1.11 2007/12/06 17:00:33 ad Exp 30 * Id: ki2c.c,v 1.7 2002/10/05 09:56:05 tsubai Exp 31 */ 32 33 /* 34 * Support routines for the Keywest I2C controller. 35 */ 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/kernel.h> 40 #include <sys/module.h> 41 #include <sys/bus.h> 42 #include <sys/lock.h> 43 #include <sys/mutex.h> 44 #include <machine/resource.h> 45 #include <machine/bus.h> 46 #include <sys/rman.h> 47 48 #include <dev/iicbus/iicbus.h> 49 #include <dev/iicbus/iiconf.h> 50 #include <dev/ofw/ofw_bus.h> 51 #include "iicbus_if.h" 52 53 /* Keywest I2C Register offsets */ 54 #define MODE 0 55 #define CONTROL 1 56 #define STATUS 2 57 #define ISR 3 58 #define IER 4 59 #define ADDR 5 60 #define SUBADDR 6 61 #define DATA 7 62 #define REV 8 63 64 /* MODE */ 65 #define I2C_SPEED 0x03 /* Speed mask */ 66 #define I2C_100kHz 0x00 67 #define I2C_50kHz 0x01 68 #define I2C_25kHz 0x02 69 #define I2C_MODE 0x0c /* Mode mask */ 70 #define I2C_DUMBMODE 0x00 /* Dumb mode */ 71 #define I2C_STDMODE 0x04 /* Standard mode */ 72 #define I2C_STDSUBMODE 0x08 /* Standard mode + sub address */ 73 #define I2C_COMBMODE 0x0c /* Combined mode */ 74 #define I2C_PORT 0xf0 /* Port mask */ 75 76 /* CONTROL */ 77 #define I2C_CT_AAK 0x01 /* Send AAK */ 78 #define I2C_CT_ADDR 0x02 /* Send address(es) */ 79 #define I2C_CT_STOP 0x04 /* Send STOP */ 80 #define I2C_CT_START 0x08 /* Send START */ 81 82 /* STATUS */ 83 #define I2C_ST_BUSY 0x01 /* Busy */ 84 #define I2C_ST_LASTAAK 0x02 /* Last AAK */ 85 #define I2C_ST_LASTRW 0x04 /* Last R/W */ 86 #define I2C_ST_SDA 0x08 /* SDA */ 87 #define I2C_ST_SCL 0x10 /* SCL */ 88 89 /* ISR/IER */ 90 #define I2C_INT_DATA 0x01 /* Data byte sent/received */ 91 #define I2C_INT_ADDR 0x02 /* Address sent */ 92 #define I2C_INT_STOP 0x04 /* STOP condition sent */ 93 #define I2C_INT_START 0x08 /* START condition sent */ 94 95 /* I2C flags */ 96 #define I2C_BUSY 0x01 97 #define I2C_READING 0x02 98 #define I2C_ERROR 0x04 99 #define I2C_SELECTED 0x08 100 101 struct kiic_softc { 102 device_t sc_dev; 103 phandle_t sc_node; 104 struct mtx sc_mutex; 105 struct resource *sc_reg; 106 int sc_irqrid; 107 struct resource *sc_irq; 108 void *sc_ih; 109 u_int sc_regstep; 110 u_int sc_flags; 111 u_char *sc_data; 112 int sc_resid; 113 uint16_t sc_i2c_base; 114 device_t sc_iicbus; 115 }; 116 117 static int kiic_probe(device_t dev); 118 static int kiic_attach(device_t dev); 119 static void kiic_writereg(struct kiic_softc *sc, u_int, u_int); 120 static u_int kiic_readreg(struct kiic_softc *, u_int); 121 static void kiic_setport(struct kiic_softc *, u_int); 122 static void kiic_setmode(struct kiic_softc *, u_int); 123 static void kiic_setspeed(struct kiic_softc *, u_int); 124 static void kiic_intr(void *xsc); 125 static int kiic_transfer(device_t dev, struct iic_msg *msgs, 126 uint32_t nmsgs); 127 static phandle_t kiic_get_node(device_t bus, device_t dev); 128 129 static device_method_t kiic_methods[] = { 130 /* device interface */ 131 DEVMETHOD(device_probe, kiic_probe), 132 DEVMETHOD(device_attach, kiic_attach), 133 134 /* iicbus interface */ 135 DEVMETHOD(iicbus_callback, iicbus_null_callback), 136 DEVMETHOD(iicbus_transfer, kiic_transfer), 137 138 /* ofw_bus interface */ 139 DEVMETHOD(ofw_bus_get_node, kiic_get_node), 140 { 0, 0 } 141 }; 142 143 static driver_t kiic_driver = { 144 "iichb", 145 kiic_methods, 146 sizeof(struct kiic_softc) 147 }; 148 static devclass_t kiic_devclass; 149 150 DRIVER_MODULE(kiic, macio, kiic_driver, kiic_devclass, 0, 0); 151 DRIVER_MODULE(kiic, unin, kiic_driver, kiic_devclass, 0, 0); 152 153 static int 154 kiic_probe(device_t self) 155 { 156 const char *name; 157 158 name = ofw_bus_get_name(self); 159 if (name && strcmp(name, "i2c") == 0) { 160 device_set_desc(self, "Keywest I2C controller"); 161 return (0); 162 } 163 164 return (ENXIO); 165 } 166 167 static int 168 kiic_attach(device_t self) 169 { 170 struct kiic_softc *sc = device_get_softc(self); 171 int rid, rate; 172 phandle_t node; 173 char name[64]; 174 175 bzero(sc, sizeof(*sc)); 176 sc->sc_dev = self; 177 178 node = ofw_bus_get_node(self); 179 if (node == 0 || node == -1) { 180 return (EINVAL); 181 } 182 183 rid = 0; 184 sc->sc_reg = bus_alloc_resource_any(self, SYS_RES_MEMORY, 185 &rid, RF_ACTIVE); 186 if (sc->sc_reg == NULL) { 187 return (ENOMEM); 188 } 189 190 if (OF_getencprop(node, "AAPL,i2c-rate", &rate, 4) != 4) { 191 device_printf(self, "cannot get i2c-rate\n"); 192 return (ENXIO); 193 } 194 if (OF_getencprop(node, "AAPL,address-step", &sc->sc_regstep, 4) != 4) { 195 device_printf(self, "unable to find i2c address step\n"); 196 return (ENXIO); 197 } 198 199 /* 200 * Some Keywest I2C devices have their children attached directly 201 * underneath them. Some have a single 'iicbus' child with the 202 * devices underneath that. Sort this out, and make sure that the 203 * OFW I2C layer has the correct node. 204 * 205 * Note: the I2C children of the Uninorth bridges have two ports. 206 * In general, the port is designated in the 9th bit of the I2C 207 * address. However, for kiic devices with children attached below 208 * an i2c-bus node, the port is indicated in the 'reg' property 209 * of the i2c-bus node. 210 */ 211 212 sc->sc_node = node; 213 214 node = OF_child(node); 215 if (OF_getprop(node, "name", name, sizeof(name)) > 0) { 216 if (strcmp(name,"i2c-bus") == 0) { 217 phandle_t reg; 218 if (OF_getprop(node, "reg", ®, sizeof(reg)) > 0) 219 sc->sc_i2c_base = reg << 8; 220 221 sc->sc_node = node; 222 } 223 } 224 225 mtx_init(&sc->sc_mutex, "kiic", NULL, MTX_DEF); 226 227 sc->sc_irq = bus_alloc_resource_any(self, SYS_RES_IRQ, &sc->sc_irqrid, 228 RF_ACTIVE); 229 bus_setup_intr(self, sc->sc_irq, INTR_TYPE_MISC | INTR_MPSAFE, NULL, 230 kiic_intr, sc, &sc->sc_ih); 231 232 kiic_writereg(sc, ISR, kiic_readreg(sc, ISR)); 233 kiic_writereg(sc, STATUS, 0); 234 kiic_writereg(sc, IER, 0); 235 236 kiic_setmode(sc, I2C_STDMODE); 237 kiic_setspeed(sc, I2C_100kHz); /* XXX rate */ 238 239 kiic_writereg(sc, IER, I2C_INT_DATA | I2C_INT_ADDR | I2C_INT_STOP); 240 241 if (bootverbose) 242 device_printf(self, "Revision: %02X\n", kiic_readreg(sc, REV)); 243 244 /* Add the IIC bus layer */ 245 sc->sc_iicbus = device_add_child(self, "iicbus", -1); 246 247 return (bus_generic_attach(self)); 248 } 249 250 static void 251 kiic_writereg(struct kiic_softc *sc, u_int reg, u_int val) 252 { 253 bus_write_4(sc->sc_reg, sc->sc_regstep * reg, val); 254 DELAY(100); /* register access delay */ 255 } 256 257 static u_int 258 kiic_readreg(struct kiic_softc *sc, u_int reg) 259 { 260 return bus_read_4(sc->sc_reg, sc->sc_regstep * reg) & 0xff; 261 } 262 263 static void 264 kiic_setmode(struct kiic_softc *sc, u_int mode) 265 { 266 u_int x; 267 268 KASSERT((mode & ~I2C_MODE) == 0, ("bad mode")); 269 x = kiic_readreg(sc, MODE); 270 x &= ~I2C_MODE; 271 x |= mode; 272 kiic_writereg(sc, MODE, x); 273 } 274 275 static void 276 kiic_setport(struct kiic_softc *sc, u_int port) 277 { 278 u_int x; 279 280 KASSERT(port == 1 || port == 0, ("bad port")); 281 x = kiic_readreg(sc, MODE); 282 x &= ~I2C_PORT; 283 x |= (port << 4); 284 kiic_writereg(sc, MODE, x); 285 } 286 287 static void 288 kiic_setspeed(struct kiic_softc *sc, u_int speed) 289 { 290 u_int x; 291 292 KASSERT((speed & ~I2C_SPEED) == 0, ("bad speed")); 293 x = kiic_readreg(sc, MODE); 294 x &= ~I2C_SPEED; 295 x |= speed; 296 kiic_writereg(sc, MODE, x); 297 } 298 299 static void 300 kiic_intr(void *xsc) 301 { 302 struct kiic_softc *sc = xsc; 303 u_int isr; 304 uint32_t x; 305 306 mtx_lock(&sc->sc_mutex); 307 isr = kiic_readreg(sc, ISR); 308 309 if (isr & I2C_INT_ADDR) { 310 sc->sc_flags |= I2C_SELECTED; 311 312 if (sc->sc_flags & I2C_READING) { 313 if (sc->sc_resid > 1) { 314 x = kiic_readreg(sc, CONTROL); 315 x |= I2C_CT_AAK; 316 kiic_writereg(sc, CONTROL, x); 317 } 318 } else { 319 kiic_writereg(sc, DATA, *sc->sc_data++); 320 sc->sc_resid--; 321 } 322 } 323 324 if (isr & I2C_INT_DATA) { 325 if (sc->sc_flags & I2C_READING) { 326 if (sc->sc_resid > 0) { 327 *sc->sc_data++ = kiic_readreg(sc, DATA); 328 sc->sc_resid--; 329 } 330 if (sc->sc_resid == 0) /* done */ 331 kiic_writereg(sc, CONTROL, 0); 332 } else { 333 if (sc->sc_resid == 0) { 334 x = kiic_readreg(sc, CONTROL); 335 x |= I2C_CT_STOP; 336 kiic_writereg(sc, CONTROL, x); 337 } else { 338 kiic_writereg(sc, DATA, *sc->sc_data++); 339 sc->sc_resid--; 340 } 341 } 342 } 343 344 if (isr & I2C_INT_STOP) { 345 kiic_writereg(sc, CONTROL, 0); 346 sc->sc_flags &= ~I2C_SELECTED; 347 wakeup(sc->sc_dev); 348 } 349 350 kiic_writereg(sc, ISR, isr); 351 mtx_unlock(&sc->sc_mutex); 352 } 353 354 static int 355 kiic_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs) 356 { 357 struct kiic_softc *sc; 358 int i, x, timo, err; 359 uint16_t addr; 360 uint8_t subaddr; 361 362 sc = device_get_softc(dev); 363 timo = 100; 364 subaddr = 0; 365 366 mtx_lock(&sc->sc_mutex); 367 368 if (sc->sc_flags & I2C_BUSY) 369 mtx_sleep(dev, &sc->sc_mutex, 0, "kiic", timo); 370 371 if (sc->sc_flags & I2C_BUSY) { 372 mtx_unlock(&sc->sc_mutex); 373 return (ETIMEDOUT); 374 } 375 376 sc->sc_flags = I2C_BUSY; 377 378 /* Clear pending interrupts, and reset controller */ 379 kiic_writereg(sc, ISR, kiic_readreg(sc, ISR)); 380 kiic_writereg(sc, STATUS, 0); 381 382 for (i = 0; i < nmsgs; i++) { 383 if (msgs[i].flags & IIC_M_NOSTOP) { 384 if (msgs[i+1].flags & IIC_M_RD) 385 kiic_setmode(sc, I2C_COMBMODE); 386 else 387 kiic_setmode(sc, I2C_STDSUBMODE); 388 KASSERT(msgs[i].len == 1, ("oversize I2C message")); 389 subaddr = msgs[i].buf[0]; 390 i++; 391 } else { 392 kiic_setmode(sc, I2C_STDMODE); 393 } 394 395 sc->sc_data = msgs[i].buf; 396 sc->sc_resid = msgs[i].len; 397 sc->sc_flags = I2C_BUSY; 398 addr = msgs[i].slave; 399 timo = 1000 + sc->sc_resid * 200; 400 timo += 100000; 401 402 if (msgs[i].flags & IIC_M_RD) { 403 sc->sc_flags |= I2C_READING; 404 addr |= 1; 405 } 406 407 addr |= sc->sc_i2c_base; 408 409 kiic_setport(sc, (addr & 0x100) >> 8); 410 kiic_writereg(sc, ADDR, addr & 0xff); 411 kiic_writereg(sc, SUBADDR, subaddr); 412 413 x = kiic_readreg(sc, CONTROL) | I2C_CT_ADDR; 414 kiic_writereg(sc, CONTROL, x); 415 416 err = mtx_sleep(dev, &sc->sc_mutex, 0, "kiic", timo); 417 418 msgs[i].len -= sc->sc_resid; 419 420 if ((sc->sc_flags & I2C_ERROR) || err == EWOULDBLOCK) { 421 device_printf(sc->sc_dev, "I2C error\n"); 422 sc->sc_flags = 0; 423 mtx_unlock(&sc->sc_mutex); 424 return (EIO); 425 } 426 } 427 428 sc->sc_flags = 0; 429 430 mtx_unlock(&sc->sc_mutex); 431 432 return (0); 433 } 434 435 static phandle_t 436 kiic_get_node(device_t bus, device_t dev) 437 { 438 struct kiic_softc *sc; 439 440 sc = device_get_softc(bus); 441 /* We only have one child, the I2C bus, which needs our own node. */ 442 443 return sc->sc_node; 444 } 445