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