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 = bus->uclass_priv; 54 int speed; 55 int ret; 56 57 speed = slave->max_hz; 58 if (spi->max_hz) { 59 if (speed) 60 speed = min(speed, spi->max_hz); 61 else 62 speed = spi->max_hz; 63 } 64 if (!speed) 65 speed = 100000; 66 ret = spi_set_speed_mode(bus, speed, slave->mode); 67 if (ret) 68 return ret; 69 70 return ops->claim_bus ? ops->claim_bus(bus) : 0; 71 } 72 73 void spi_release_bus(struct spi_slave *slave) 74 { 75 struct udevice *dev = slave->dev; 76 struct udevice *bus = dev->parent; 77 struct dm_spi_ops *ops = spi_get_ops(bus); 78 79 if (ops->release_bus) 80 ops->release_bus(bus); 81 } 82 83 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, 84 const void *dout, void *din, unsigned long flags) 85 { 86 struct udevice *dev = slave->dev; 87 struct udevice *bus = dev->parent; 88 89 if (bus->uclass->uc_drv->id != UCLASS_SPI) 90 return -EOPNOTSUPP; 91 92 return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags); 93 } 94 95 int spi_post_bind(struct udevice *dev) 96 { 97 /* Scan the bus for devices */ 98 return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false); 99 } 100 101 int spi_post_probe(struct udevice *dev) 102 { 103 struct dm_spi_bus *spi = dev->uclass_priv; 104 105 spi->max_hz = fdtdec_get_int(gd->fdt_blob, dev->of_offset, 106 "spi-max-frequency", 0); 107 108 return 0; 109 } 110 111 int spi_chip_select(struct udevice *dev) 112 { 113 struct spi_slave *slave = dev_get_parentdata(dev); 114 115 return slave ? slave->cs : -ENOENT; 116 } 117 118 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp) 119 { 120 struct udevice *dev; 121 122 for (device_find_first_child(bus, &dev); dev; 123 device_find_next_child(&dev)) { 124 struct spi_slave store; 125 struct spi_slave *slave = dev_get_parentdata(dev); 126 127 if (!slave) { 128 slave = &store; 129 spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, 130 slave); 131 } 132 debug("%s: slave=%p, cs=%d\n", __func__, slave, 133 slave ? slave->cs : -1); 134 if (slave && slave->cs == cs) { 135 *devp = dev; 136 return 0; 137 } 138 } 139 140 return -ENODEV; 141 } 142 143 int spi_cs_is_valid(unsigned int busnum, unsigned int cs) 144 { 145 struct spi_cs_info info; 146 struct udevice *bus; 147 int ret; 148 149 ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus); 150 if (ret) { 151 debug("%s: No bus %d\n", __func__, busnum); 152 return ret; 153 } 154 155 return spi_cs_info(bus, cs, &info); 156 } 157 158 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info) 159 { 160 struct spi_cs_info local_info; 161 struct dm_spi_ops *ops; 162 int ret; 163 164 if (!info) 165 info = &local_info; 166 167 /* If there is a device attached, return it */ 168 info->dev = NULL; 169 ret = spi_find_chip_select(bus, cs, &info->dev); 170 if (!ret) 171 return 0; 172 173 /* 174 * Otherwise ask the driver. For the moment we don't have CS info. 175 * When we do we could provide the driver with a helper function 176 * to figure out what chip selects are valid, or just handle the 177 * request. 178 */ 179 ops = spi_get_ops(bus); 180 if (ops->cs_info) 181 return ops->cs_info(bus, cs, info); 182 183 /* 184 * We could assume there is at least one valid chip select, but best 185 * to be sure and return an error in this case. The driver didn't 186 * care enough to tell us. 187 */ 188 return -ENODEV; 189 } 190 191 int spi_bind_device(struct udevice *bus, int cs, const char *drv_name, 192 const char *dev_name, struct udevice **devp) 193 { 194 struct driver *drv; 195 int ret; 196 197 drv = lists_driver_lookup_name(drv_name); 198 if (!drv) { 199 printf("Cannot find driver '%s'\n", drv_name); 200 return -ENOENT; 201 } 202 ret = device_bind(bus, drv, dev_name, NULL, -1, devp); 203 if (ret) { 204 printf("Cannot create device named '%s' (err=%d)\n", 205 dev_name, ret); 206 return ret; 207 } 208 209 return 0; 210 } 211 212 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 213 struct udevice **devp) 214 { 215 struct udevice *bus, *dev; 216 int ret; 217 218 ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus); 219 if (ret) { 220 debug("%s: No bus %d\n", __func__, busnum); 221 return ret; 222 } 223 ret = spi_find_chip_select(bus, cs, &dev); 224 if (ret) { 225 debug("%s: No cs %d\n", __func__, cs); 226 return ret; 227 } 228 *busp = bus; 229 *devp = dev; 230 231 return ret; 232 } 233 234 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 235 const char *drv_name, const char *dev_name, 236 struct udevice **busp, struct spi_slave **devp) 237 { 238 struct udevice *bus, *dev; 239 struct spi_slave *slave; 240 bool created = false; 241 int ret; 242 243 ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus); 244 if (ret) { 245 printf("Invalid bus %d (err=%d)\n", busnum, ret); 246 return ret; 247 } 248 ret = spi_find_chip_select(bus, cs, &dev); 249 250 /* 251 * If there is no such device, create one automatically. This means 252 * that we don't need a device tree node or platform data for the 253 * SPI flash chip - we will bind to the correct driver. 254 */ 255 if (ret == -ENODEV && drv_name) { 256 debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n", 257 __func__, dev_name, busnum, cs, drv_name); 258 ret = spi_bind_device(bus, cs, drv_name, dev_name, &dev); 259 if (ret) 260 return ret; 261 created = true; 262 } else if (ret) { 263 printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs, 264 ret); 265 return ret; 266 } 267 268 if (!device_active(dev)) { 269 slave = (struct spi_slave *)calloc(1, 270 sizeof(struct spi_slave)); 271 if (!slave) { 272 ret = -ENOMEM; 273 goto err; 274 } 275 276 ret = spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, 277 slave); 278 if (ret) 279 goto err; 280 slave->cs = cs; 281 slave->dev = dev; 282 ret = device_probe_child(dev, slave); 283 free(slave); 284 if (ret) 285 goto err; 286 } 287 288 ret = spi_set_speed_mode(bus, speed, mode); 289 if (ret) 290 goto err; 291 292 *busp = bus; 293 *devp = dev_get_parentdata(dev); 294 debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp); 295 296 return 0; 297 298 err: 299 if (created) { 300 device_remove(dev); 301 device_unbind(dev); 302 } 303 304 return ret; 305 } 306 307 /* Compatibility function - to be removed */ 308 struct spi_slave *spi_setup_slave_fdt(const void *blob, int node, 309 int bus_node) 310 { 311 struct udevice *bus, *dev; 312 int ret; 313 314 ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus); 315 if (ret) 316 return NULL; 317 ret = device_get_child_by_of_offset(bus, node, &dev); 318 if (ret) 319 return NULL; 320 return dev_get_parentdata(dev); 321 } 322 323 /* Compatibility function - to be removed */ 324 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs, 325 unsigned int speed, unsigned int mode) 326 { 327 struct spi_slave *slave; 328 struct udevice *dev; 329 int ret; 330 331 ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev, 332 &slave); 333 if (ret) 334 return NULL; 335 336 return slave; 337 } 338 339 void spi_free_slave(struct spi_slave *slave) 340 { 341 device_remove(slave->dev); 342 slave->dev = NULL; 343 } 344 345 int spi_ofdata_to_platdata(const void *blob, int node, 346 struct spi_slave *spi) 347 { 348 int mode = 0; 349 350 spi->cs = fdtdec_get_int(blob, node, "reg", -1); 351 spi->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0); 352 if (fdtdec_get_bool(blob, node, "spi-cpol")) 353 mode |= SPI_CPOL; 354 if (fdtdec_get_bool(blob, node, "spi-cpha")) 355 mode |= SPI_CPHA; 356 if (fdtdec_get_bool(blob, node, "spi-cs-high")) 357 mode |= SPI_CS_HIGH; 358 if (fdtdec_get_bool(blob, node, "spi-half-duplex")) 359 mode |= SPI_PREAMBLE; 360 spi->mode = mode; 361 362 return 0; 363 } 364 365 UCLASS_DRIVER(spi) = { 366 .id = UCLASS_SPI, 367 .name = "spi", 368 .post_bind = spi_post_bind, 369 .post_probe = spi_post_probe, 370 .per_device_auto_alloc_size = sizeof(struct dm_spi_bus), 371 }; 372 373 UCLASS_DRIVER(spi_generic) = { 374 .id = UCLASS_SPI_GENERIC, 375 .name = "spi_generic", 376 }; 377 378 U_BOOT_DRIVER(spi_generic_drv) = { 379 .name = "spi_generic_drv", 380 .id = UCLASS_SPI_GENERIC, 381 }; 382