1/*- 2 * Copyright (c) 2011, Aleksandr Rybalko <ray@dlink.ua> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * 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 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD: releng/11.0/sys/dev/gpio/gpiospi.c 300715 2016-05-26 07:20:33Z adrian $"); 30 31#include "opt_gpio.h" 32 33#include <sys/param.h> 34#include <sys/systm.h> 35 36#include <sys/bus.h> 37#include <sys/kernel.h> 38#include <sys/module.h> 39#include <sys/rman.h> 40#include <sys/sysctl.h> 41 42#include <sys/gpio.h> 43#include "gpiobus_if.h" 44 45#include <dev/gpio/gpiobusvar.h> 46 47#include <dev/spibus/spi.h> 48#include <dev/spibus/spibusvar.h> 49#include "spibus_if.h" 50 51#ifdef GPIO_SPI_DEBUG 52#define dprintf printf 53#else 54#define dprintf(x, arg...) 55#endif /* GPIO_SPI_DEBUG */ 56 57struct gpio_spi_softc { 58 device_t sc_dev; 59 device_t sc_busdev; 60 int sc_freq; 61 uint8_t sc_sclk; 62 uint8_t sc_miso; 63 uint8_t sc_mosi; 64 uint8_t sc_cs0; 65 uint8_t sc_cs1; 66 uint8_t sc_cs2; 67 uint8_t sc_cs3; 68}; 69 70static void gpio_spi_chip_activate(struct gpio_spi_softc *, int); 71static void gpio_spi_chip_deactivate(struct gpio_spi_softc *, int); 72 73static int 74gpio_spi_probe(device_t dev) 75{ 76 device_set_desc(dev, "GPIO SPI bit-banging driver"); 77 return (0); 78} 79 80static void 81gpio_delay(struct gpio_spi_softc *sc) 82{ 83 int d; 84 85 d = sc->sc_freq / 1000000; 86 if (d == 0) 87 d = 1; 88 89 DELAY(d); 90} 91 92static int 93gpio_spi_attach(device_t dev) 94{ 95 uint32_t value; 96 struct gpio_spi_softc *sc; 97 98 sc = device_get_softc(dev); 99 sc->sc_dev = dev; 100 sc->sc_busdev = device_get_parent(dev); 101 102 /* Required variables */ 103 if (resource_int_value(device_get_name(dev), 104 device_get_unit(dev), "sclk", &value)) 105 return (ENXIO); 106 sc->sc_sclk = value & 0xff; 107 108 if (resource_int_value(device_get_name(dev), 109 device_get_unit(dev), "mosi", &value)) 110 return (ENXIO); 111 sc->sc_mosi = value & 0xff; 112 113 /* Handle no miso; we just never read back from the device */ 114 if (resource_int_value(device_get_name(dev), 115 device_get_unit(dev), "miso", &value)) 116 value = 0xff; 117 sc->sc_miso = value & 0xff; 118 119 if (resource_int_value(device_get_name(dev), 120 device_get_unit(dev), "cs0", &value)) 121 return (ENXIO); 122 sc->sc_cs0 = value & 0xff; 123 124 /* Optional variables */ 125 if (resource_int_value(device_get_name(dev), 126 device_get_unit(dev), "cs1", &value)) 127 value = 0xff; 128 sc->sc_cs1 = value & 0xff; 129 130 if (resource_int_value(device_get_name(dev), 131 device_get_unit(dev), "cs2", &value)) 132 value = 0xff; 133 sc->sc_cs2 = value & 0xff; 134 135 if (resource_int_value(device_get_name(dev), 136 device_get_unit(dev), "cs3", &value)) 137 value = 0xff; 138 sc->sc_cs3 = value & 0xff; 139 140 /* Default to 100KHz */ 141 if (resource_int_value(device_get_name(dev), 142 device_get_unit(dev), "freq", &value)) { 143 value = 100000; 144 } 145 sc->sc_freq = value; 146 147 if (bootverbose) { 148 device_printf(dev, "frequency: %d Hz\n", 149 sc->sc_freq); 150 device_printf(dev, 151 "Use GPIO pins: sclk=%d, mosi=%d, miso=%d, " 152 "cs0=%d, cs1=%d, cs2=%d, cs3=%d\n", 153 sc->sc_sclk, sc->sc_mosi, sc->sc_miso, 154 sc->sc_cs0, sc->sc_cs1, sc->sc_cs2, sc->sc_cs3); 155 } 156 157 /* Set directions */ 158 GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, sc->sc_sclk, 159 GPIO_PIN_OUTPUT|GPIO_PIN_PULLDOWN); 160 GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, sc->sc_mosi, 161 GPIO_PIN_OUTPUT|GPIO_PIN_PULLDOWN); 162 if (sc->sc_miso != 0xff) { 163 GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, sc->sc_miso, 164 GPIO_PIN_INPUT|GPIO_PIN_PULLDOWN); 165 } 166 167 GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, sc->sc_cs0, 168 GPIO_PIN_OUTPUT|GPIO_PIN_PULLUP); 169 170 if (sc->sc_cs1 != 0xff) 171 GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, sc->sc_cs1, 172 GPIO_PIN_OUTPUT|GPIO_PIN_PULLUP); 173 if (sc->sc_cs2 != 0xff) 174 GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, sc->sc_cs2, 175 GPIO_PIN_OUTPUT|GPIO_PIN_PULLUP); 176 if (sc->sc_cs3 != 0xff) 177 GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, sc->sc_cs3, 178 GPIO_PIN_OUTPUT|GPIO_PIN_PULLUP); 179 180 gpio_spi_chip_deactivate(sc, -1); 181 182 device_add_child(dev, "spibus", -1); 183 return (bus_generic_attach(dev)); 184} 185 186static int 187gpio_spi_detach(device_t dev) 188{ 189 190 return (0); 191} 192 193static void 194gpio_spi_chip_activate(struct gpio_spi_softc *sc, int cs) 195{ 196 197 /* called with locked gpiobus */ 198 switch (cs) { 199 case 0: 200 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 201 sc->sc_cs0, 0); 202 break; 203 case 1: 204 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 205 sc->sc_cs1, 0); 206 break; 207 case 2: 208 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 209 sc->sc_cs2, 0); 210 break; 211 case 3: 212 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 213 sc->sc_cs3, 0); 214 break; 215 default: 216 device_printf(sc->sc_dev, "don't have CS%d\n", cs); 217 } 218 219 gpio_delay(sc); 220} 221 222static void 223gpio_spi_chip_deactivate(struct gpio_spi_softc *sc, int cs) 224{ 225 226 /* called wth locked gpiobus */ 227 /* 228 * Put CSx to high 229 */ 230 switch (cs) { 231 case -1: 232 /* All CS */ 233 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 234 sc->sc_cs0, 1); 235 if (sc->sc_cs1 == 0xff) break; 236 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 237 sc->sc_cs1, 1); 238 if (sc->sc_cs2 == 0xff) break; 239 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 240 sc->sc_cs2, 1); 241 if (sc->sc_cs3 == 0xff) break; 242 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 243 sc->sc_cs3, 1); 244 break; 245 case 0: 246 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 247 sc->sc_cs0, 1); 248 break; 249 case 1: 250 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 251 sc->sc_cs1, 1); 252 break; 253 case 2: 254 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 255 sc->sc_cs2, 1); 256 break; 257 case 3: 258 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 259 sc->sc_cs3, 1); 260 break; 261 default: 262 device_printf(sc->sc_dev, "don't have CS%d\n", cs); 263 } 264} 265 266static uint8_t 267gpio_spi_txrx(struct gpio_spi_softc *sc, int cs, int mode, uint8_t data) 268{ 269 uint32_t mask, out = 0; 270 unsigned int bit; 271 272 273 /* called with locked gpiobus */ 274 275 for (mask = 0x80; mask > 0; mask >>= 1) { 276 if ((mode == SPIBUS_MODE_CPOL) || 277 (mode == SPIBUS_MODE_CPHA)) { 278 /* If mode 1 or 2 */ 279 280 /* first step */ 281 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 282 sc->sc_mosi, (data & mask)?1:0); 283 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 284 sc->sc_sclk, 0); 285 gpio_delay(sc); 286 /* second step */ 287 if (sc->sc_miso != 0xff) { 288 GPIOBUS_PIN_GET(sc->sc_busdev, sc->sc_dev, 289 sc->sc_miso, &bit); 290 out |= bit?mask:0; 291 } 292 /* Data captured */ 293 gpio_delay(sc); 294 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 295 sc->sc_sclk, 1); 296 } else { 297 /* If mode 0 or 3 */ 298 299 /* first step */ 300 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 301 sc->sc_mosi, (data & mask)?1:0); 302 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 303 sc->sc_sclk, 1); 304 gpio_delay(sc); 305 /* second step */ 306 if (sc->sc_miso != 0xff) { 307 GPIOBUS_PIN_GET(sc->sc_busdev, sc->sc_dev, 308 sc->sc_miso, &bit); 309 out |= bit?mask:0; 310 } 311 /* Data captured */ 312 gpio_delay(sc); 313 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 314 sc->sc_sclk, 0); 315 } 316 } 317 318 return (out & 0xff); 319} 320 321static int 322gpio_spi_transfer(device_t dev, device_t child, struct spi_command *cmd) 323{ 324 struct gpio_spi_softc *sc; 325 uint8_t *buf_in, *buf_out; 326 struct spibus_ivar *devi = SPIBUS_IVAR(child); 327 int i; 328 329 sc = device_get_softc(dev); 330 331 KASSERT(cmd->tx_cmd_sz == cmd->rx_cmd_sz, 332 ("TX/RX command sizes should be equal")); 333 KASSERT(cmd->tx_data_sz == cmd->rx_data_sz, 334 ("TX/RX data sizes should be equal")); 335 336 gpio_spi_chip_activate(sc, devi->cs); 337 338 /* Preset pins */ 339 if ((devi->mode == SPIBUS_MODE_CPOL) || 340 (devi->mode == SPIBUS_MODE_CPHA)) { 341 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 342 sc->sc_sclk, 1); 343 } else { 344 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 345 sc->sc_sclk, 0); 346 } 347 348 /* 349 * Transfer command 350 */ 351 buf_out = (uint8_t *)cmd->tx_cmd; 352 buf_in = (uint8_t *)cmd->rx_cmd; 353 354 for (i = 0; i < cmd->tx_cmd_sz; i++) 355 buf_in[i] = gpio_spi_txrx(sc, devi->cs, devi->mode, buf_out[i]); 356 357 /* 358 * Receive/transmit data (depends on command) 359 */ 360 buf_out = (uint8_t *)cmd->tx_data; 361 buf_in = (uint8_t *)cmd->rx_data; 362 for (i = 0; i < cmd->tx_data_sz; i++) 363 buf_in[i] = gpio_spi_txrx(sc, devi->cs, devi->mode, buf_out[i]); 364 365 /* Return pins to mode default */ 366 if ((devi->mode == SPIBUS_MODE_CPOL) || 367 (devi->mode == SPIBUS_MODE_CPHA)) { 368 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 369 sc->sc_sclk, 1); 370 } else { 371 GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, 372 sc->sc_sclk, 0); 373 } 374 375 gpio_spi_chip_deactivate(sc, devi->cs); 376 377 return (0); 378} 379 380static device_method_t gpio_spi_methods[] = { 381 /* Device interface */ 382 DEVMETHOD(device_probe, gpio_spi_probe), 383 DEVMETHOD(device_attach, gpio_spi_attach), 384 DEVMETHOD(device_detach, gpio_spi_detach), 385 386 DEVMETHOD(spibus_transfer, gpio_spi_transfer), 387 388 {0, 0} 389}; 390 391static driver_t gpio_spi_driver = { 392 "gpiospi", 393 gpio_spi_methods, 394 sizeof(struct gpio_spi_softc), 395}; 396 397static devclass_t gpio_spi_devclass; 398 399DRIVER_MODULE(gpiospi, gpiobus, gpio_spi_driver, gpio_spi_devclass, 0, 0); 400DRIVER_MODULE(spibus, gpiospi, spibus_driver, spibus_devclass, 0, 0); 401MODULE_DEPEND(spi, gpiospi, 1, 1, 1); 402MODULE_DEPEND(gpiobus, gpiospi, 1, 1, 1); 403