1 /* 2 * Copyright (c) 2014 Google, Inc 3 * 4 * SPDX-License-Identifier: GPL-2.0+ 5 */ 6 7 #include <common.h> 8 #include <dm.h> 9 #include <errno.h> 10 #include <fdtdec.h> 11 #include <malloc.h> 12 #include <spi.h> 13 #include <dm/device-internal.h> 14 #include <dm/uclass-internal.h> 15 #include <dm/root.h> 16 #include <dm/lists.h> 17 #include <dm/util.h> 18 19 DECLARE_GLOBAL_DATA_PTR; 20 21 static int spi_set_speed_mode(struct udevice *bus, int speed, int mode) 22 { 23 struct dm_spi_ops *ops; 24 int ret; 25 26 ops = spi_get_ops(bus); 27 if (ops->set_speed) 28 ret = ops->set_speed(bus, speed); 29 else 30 ret = -EINVAL; 31 if (ret) { 32 printf("Cannot set speed (err=%d)\n", ret); 33 return ret; 34 } 35 36 if (ops->set_mode) 37 ret = ops->set_mode(bus, mode); 38 else 39 ret = -EINVAL; 40 if (ret) { 41 printf("Cannot set mode (err=%d)\n", ret); 42 return ret; 43 } 44 45 return 0; 46 } 47 48 int spi_claim_bus(struct spi_slave *slave) 49 { 50 struct udevice *dev = slave->dev; 51 struct udevice *bus = dev->parent; 52 struct dm_spi_ops *ops = spi_get_ops(bus); 53 struct dm_spi_bus *spi = dev_get_uclass_priv(bus); 54 int speed; 55 int ret; 56 57 speed = slave->max_hz; 58 if (spi->max_hz) { 59 if (speed) 60 speed = min(speed, (int)spi->max_hz); 61 else 62 speed = spi->max_hz; 63 } 64 if (!speed) 65 speed = 100000; 66 if (speed != slave->speed) { 67 ret = spi_set_speed_mode(bus, speed, slave->mode); 68 if (ret) 69 return ret; 70 slave->speed = speed; 71 } 72 73 return ops->claim_bus ? ops->claim_bus(dev) : 0; 74 } 75 76 void spi_release_bus(struct spi_slave *slave) 77 { 78 struct udevice *dev = slave->dev; 79 struct udevice *bus = dev->parent; 80 struct dm_spi_ops *ops = spi_get_ops(bus); 81 82 if (ops->release_bus) 83 ops->release_bus(dev); 84 } 85 86 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, 87 const void *dout, void *din, unsigned long flags) 88 { 89 struct udevice *dev = slave->dev; 90 struct udevice *bus = dev->parent; 91 92 if (bus->uclass->uc_drv->id != UCLASS_SPI) 93 return -EOPNOTSUPP; 94 95 return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags); 96 } 97 98 static int spi_post_bind(struct udevice *dev) 99 { 100 /* Scan the bus for devices */ 101 return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false); 102 } 103 104 static int spi_child_post_bind(struct udevice *dev) 105 { 106 struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev); 107 108 if (dev->of_offset == -1) 109 return 0; 110 111 return spi_slave_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, plat); 112 } 113 114 static int spi_post_probe(struct udevice *bus) 115 { 116 struct dm_spi_bus *spi = dev_get_uclass_priv(bus); 117 118 spi->max_hz = fdtdec_get_int(gd->fdt_blob, bus->of_offset, 119 "spi-max-frequency", 0); 120 121 #if defined(CONFIG_NEEDS_MANUAL_RELOC) 122 struct dm_spi_ops *ops = spi_get_ops(bus); 123 124 125 if (ops->claim_bus) 126 ops->claim_bus += gd->reloc_off; 127 if (ops->release_bus) 128 ops->release_bus += gd->reloc_off; 129 if (ops->set_wordlen) 130 ops->set_wordlen += gd->reloc_off; 131 if (ops->xfer) 132 ops->xfer += gd->reloc_off; 133 if (ops->set_speed) 134 ops->set_speed += gd->reloc_off; 135 if (ops->set_mode) 136 ops->set_mode += gd->reloc_off; 137 if (ops->cs_info) 138 ops->cs_info += gd->reloc_off; 139 #endif 140 141 return 0; 142 } 143 144 static int spi_child_pre_probe(struct udevice *dev) 145 { 146 struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev); 147 struct spi_slave *slave = dev_get_parent_priv(dev); 148 149 /* 150 * This is needed because we pass struct spi_slave around the place 151 * instead slave->dev (a struct udevice). So we have to have some 152 * way to access the slave udevice given struct spi_slave. Once we 153 * change the SPI API to use udevice instead of spi_slave, we can 154 * drop this. 155 */ 156 slave->dev = dev; 157 158 slave->max_hz = plat->max_hz; 159 slave->mode = plat->mode; 160 161 return 0; 162 } 163 164 int spi_chip_select(struct udevice *dev) 165 { 166 struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev); 167 168 return plat ? plat->cs : -ENOENT; 169 } 170 171 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp) 172 { 173 struct udevice *dev; 174 175 for (device_find_first_child(bus, &dev); dev; 176 device_find_next_child(&dev)) { 177 struct dm_spi_slave_platdata *plat; 178 179 plat = dev_get_parent_platdata(dev); 180 debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs); 181 if (plat->cs == cs) { 182 *devp = dev; 183 return 0; 184 } 185 } 186 187 return -ENODEV; 188 } 189 190 int spi_cs_is_valid(unsigned int busnum, unsigned int cs) 191 { 192 struct spi_cs_info info; 193 struct udevice *bus; 194 int ret; 195 196 ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus); 197 if (ret) { 198 debug("%s: No bus %d\n", __func__, busnum); 199 return ret; 200 } 201 202 return spi_cs_info(bus, cs, &info); 203 } 204 205 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info) 206 { 207 struct spi_cs_info local_info; 208 struct dm_spi_ops *ops; 209 int ret; 210 211 if (!info) 212 info = &local_info; 213 214 /* If there is a device attached, return it */ 215 info->dev = NULL; 216 ret = spi_find_chip_select(bus, cs, &info->dev); 217 if (!ret) 218 return 0; 219 220 /* 221 * Otherwise ask the driver. For the moment we don't have CS info. 222 * When we do we could provide the driver with a helper function 223 * to figure out what chip selects are valid, or just handle the 224 * request. 225 */ 226 ops = spi_get_ops(bus); 227 if (ops->cs_info) 228 return ops->cs_info(bus, cs, info); 229 230 /* 231 * We could assume there is at least one valid chip select, but best 232 * to be sure and return an error in this case. The driver didn't 233 * care enough to tell us. 234 */ 235 return -ENODEV; 236 } 237 238 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 239 struct udevice **devp) 240 { 241 struct udevice *bus, *dev; 242 int ret; 243 244 ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus); 245 if (ret) { 246 debug("%s: No bus %d\n", __func__, busnum); 247 return ret; 248 } 249 ret = spi_find_chip_select(bus, cs, &dev); 250 if (ret) { 251 debug("%s: No cs %d\n", __func__, cs); 252 return ret; 253 } 254 *busp = bus; 255 *devp = dev; 256 257 return ret; 258 } 259 260 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 261 const char *drv_name, const char *dev_name, 262 struct udevice **busp, struct spi_slave **devp) 263 { 264 struct udevice *bus, *dev; 265 bool created = false; 266 int ret; 267 268 ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus); 269 if (ret) { 270 printf("Invalid bus %d (err=%d)\n", busnum, ret); 271 return ret; 272 } 273 ret = spi_find_chip_select(bus, cs, &dev); 274 275 /* 276 * If there is no such device, create one automatically. This means 277 * that we don't need a device tree node or platform data for the 278 * SPI flash chip - we will bind to the correct driver. 279 */ 280 if (ret == -ENODEV && drv_name) { 281 struct dm_spi_slave_platdata *plat; 282 283 debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n", 284 __func__, dev_name, busnum, cs, drv_name); 285 ret = device_bind_driver(bus, drv_name, dev_name, &dev); 286 if (ret) 287 return ret; 288 plat = dev_get_parent_platdata(dev); 289 plat->cs = cs; 290 plat->max_hz = speed; 291 plat->mode = mode; 292 created = true; 293 } else if (ret) { 294 printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs, 295 ret); 296 return ret; 297 } 298 299 if (!device_active(dev)) { 300 struct spi_slave *slave; 301 302 ret = device_probe(dev); 303 if (ret) 304 goto err; 305 slave = dev_get_parent_priv(dev); 306 slave->dev = dev; 307 } 308 309 ret = spi_set_speed_mode(bus, speed, mode); 310 if (ret) 311 goto err; 312 313 *busp = bus; 314 *devp = dev_get_parent_priv(dev); 315 debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp); 316 317 return 0; 318 319 err: 320 debug("%s: Error path, credted=%d, device '%s'\n", __func__, 321 created, dev->name); 322 if (created) { 323 device_remove(dev); 324 device_unbind(dev); 325 } 326 327 return ret; 328 } 329 330 /* Compatibility function - to be removed */ 331 struct spi_slave *spi_setup_slave_fdt(const void *blob, int node, 332 int bus_node) 333 { 334 struct udevice *bus, *dev; 335 int ret; 336 337 ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus); 338 if (ret) 339 return NULL; 340 ret = device_get_child_by_of_offset(bus, node, &dev); 341 if (ret) 342 return NULL; 343 return dev_get_parent_priv(dev); 344 } 345 346 /* Compatibility function - to be removed */ 347 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs, 348 unsigned int speed, unsigned int mode) 349 { 350 struct spi_slave *slave; 351 struct udevice *dev; 352 int ret; 353 354 ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev, 355 &slave); 356 if (ret) 357 return NULL; 358 359 return slave; 360 } 361 362 void spi_free_slave(struct spi_slave *slave) 363 { 364 device_remove(slave->dev); 365 slave->dev = NULL; 366 } 367 368 int spi_slave_ofdata_to_platdata(const void *blob, int node, 369 struct dm_spi_slave_platdata *plat) 370 { 371 int mode = 0; 372 373 plat->cs = fdtdec_get_int(blob, node, "reg", -1); 374 plat->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0); 375 if (fdtdec_get_bool(blob, node, "spi-cpol")) 376 mode |= SPI_CPOL; 377 if (fdtdec_get_bool(blob, node, "spi-cpha")) 378 mode |= SPI_CPHA; 379 if (fdtdec_get_bool(blob, node, "spi-cs-high")) 380 mode |= SPI_CS_HIGH; 381 if (fdtdec_get_bool(blob, node, "spi-half-duplex")) 382 mode |= SPI_PREAMBLE; 383 plat->mode = mode; 384 385 return 0; 386 } 387 388 UCLASS_DRIVER(spi) = { 389 .id = UCLASS_SPI, 390 .name = "spi", 391 .flags = DM_UC_FLAG_SEQ_ALIAS, 392 .post_bind = spi_post_bind, 393 .post_probe = spi_post_probe, 394 .child_pre_probe = spi_child_pre_probe, 395 .per_device_auto_alloc_size = sizeof(struct dm_spi_bus), 396 .per_child_auto_alloc_size = sizeof(struct spi_slave), 397 .per_child_platdata_auto_alloc_size = 398 sizeof(struct dm_spi_slave_platdata), 399 .child_post_bind = spi_child_post_bind, 400 }; 401 402 UCLASS_DRIVER(spi_generic) = { 403 .id = UCLASS_SPI_GENERIC, 404 .name = "spi_generic", 405 }; 406 407 U_BOOT_DRIVER(spi_generic_drv) = { 408 .name = "spi_generic_drv", 409 .id = UCLASS_SPI_GENERIC, 410 }; 411