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_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_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 192 struct udevice **devp) 193 { 194 struct udevice *bus, *dev; 195 int ret; 196 197 ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus); 198 if (ret) { 199 debug("%s: No bus %d\n", __func__, busnum); 200 return ret; 201 } 202 ret = spi_find_chip_select(bus, cs, &dev); 203 if (ret) { 204 debug("%s: No cs %d\n", __func__, cs); 205 return ret; 206 } 207 *busp = bus; 208 *devp = dev; 209 210 return ret; 211 } 212 213 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 214 const char *drv_name, const char *dev_name, 215 struct udevice **busp, struct spi_slave **devp) 216 { 217 struct udevice *bus, *dev; 218 struct spi_slave *slave; 219 bool created = false; 220 int ret; 221 222 ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus); 223 if (ret) { 224 printf("Invalid bus %d (err=%d)\n", busnum, ret); 225 return ret; 226 } 227 ret = spi_find_chip_select(bus, cs, &dev); 228 229 /* 230 * If there is no such device, create one automatically. This means 231 * that we don't need a device tree node or platform data for the 232 * SPI flash chip - we will bind to the correct driver. 233 */ 234 if (ret == -ENODEV && drv_name) { 235 debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n", 236 __func__, dev_name, busnum, cs, drv_name); 237 ret = device_bind_driver(bus, drv_name, dev_name, &dev); 238 if (ret) 239 return ret; 240 created = true; 241 } else if (ret) { 242 printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs, 243 ret); 244 return ret; 245 } 246 247 if (!device_active(dev)) { 248 slave = (struct spi_slave *)calloc(1, 249 sizeof(struct spi_slave)); 250 if (!slave) { 251 ret = -ENOMEM; 252 goto err; 253 } 254 255 ret = spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, 256 slave); 257 if (ret) 258 goto err; 259 slave->cs = cs; 260 slave->dev = dev; 261 ret = device_probe_child(dev, slave); 262 free(slave); 263 if (ret) 264 goto err; 265 } 266 267 ret = spi_set_speed_mode(bus, speed, mode); 268 if (ret) 269 goto err; 270 271 *busp = bus; 272 *devp = dev_get_parentdata(dev); 273 debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp); 274 275 return 0; 276 277 err: 278 if (created) { 279 device_remove(dev); 280 device_unbind(dev); 281 } 282 283 return ret; 284 } 285 286 /* Compatibility function - to be removed */ 287 struct spi_slave *spi_setup_slave_fdt(const void *blob, int node, 288 int bus_node) 289 { 290 struct udevice *bus, *dev; 291 int ret; 292 293 ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus); 294 if (ret) 295 return NULL; 296 ret = device_get_child_by_of_offset(bus, node, &dev); 297 if (ret) 298 return NULL; 299 return dev_get_parentdata(dev); 300 } 301 302 /* Compatibility function - to be removed */ 303 struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs, 304 unsigned int speed, unsigned int mode) 305 { 306 struct spi_slave *slave; 307 struct udevice *dev; 308 int ret; 309 310 ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev, 311 &slave); 312 if (ret) 313 return NULL; 314 315 return slave; 316 } 317 318 void spi_free_slave(struct spi_slave *slave) 319 { 320 device_remove(slave->dev); 321 slave->dev = NULL; 322 } 323 324 int spi_ofdata_to_platdata(const void *blob, int node, 325 struct spi_slave *spi) 326 { 327 int mode = 0; 328 329 spi->cs = fdtdec_get_int(blob, node, "reg", -1); 330 spi->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0); 331 if (fdtdec_get_bool(blob, node, "spi-cpol")) 332 mode |= SPI_CPOL; 333 if (fdtdec_get_bool(blob, node, "spi-cpha")) 334 mode |= SPI_CPHA; 335 if (fdtdec_get_bool(blob, node, "spi-cs-high")) 336 mode |= SPI_CS_HIGH; 337 if (fdtdec_get_bool(blob, node, "spi-half-duplex")) 338 mode |= SPI_PREAMBLE; 339 spi->mode = mode; 340 341 return 0; 342 } 343 344 UCLASS_DRIVER(spi) = { 345 .id = UCLASS_SPI, 346 .name = "spi", 347 .post_bind = spi_post_bind, 348 .post_probe = spi_post_probe, 349 .per_device_auto_alloc_size = sizeof(struct dm_spi_bus), 350 }; 351 352 UCLASS_DRIVER(spi_generic) = { 353 .id = UCLASS_SPI_GENERIC, 354 .name = "spi_generic", 355 }; 356 357 U_BOOT_DRIVER(spi_generic_drv) = { 358 .name = "spi_generic_drv", 359 .id = UCLASS_SPI_GENERIC, 360 }; 361