drivers/spi/spi_imx.c

   1 /*
   2  * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   3  * Copyright (C) 2008 Juergen Beisert
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the
  16  * Free Software Foundation
  17  * 51 Franklin Street, Fifth Floor
  18  * Boston, MA  02110-1301, USA.
  19  */
  20
  21 #include <linux/clk.h>
  22 #include <linux/completion.h>
  23 #include <linux/delay.h>
  24 #include <linux/err.h>
  25 #include <linux/gpio.h>
  26 #include <linux/init.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/io.h>
  29 #include <linux/irq.h>
  30 #include <linux/kernel.h>
  31 #include <linux/module.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/spi/spi.h>
  34 #include <linux/spi/spi_bitbang.h>
  35 #include <linux/types.h>
  36
  37 #include <mach/spi.h>
  38
  39 #define DRIVER_NAME "spi_imx"
  40
  41 #define MXC_CSPIRXDATA          0x00
  42 #define MXC_CSPITXDATA          0x04
  43 #define MXC_CSPICTRL            0x08
  44 #define MXC_CSPIINT             0x0c
  45 #define MXC_RESET               0x1c
  46
  47 /* generic defines to abstract from the different register layouts */
  48 #define MXC_INT_RR      (1 << 0) /* Receive data ready interrupt */
  49 #define MXC_INT_TE      (1 << 1) /* Transmit FIFO empty interrupt */
  50
  51 struct spi_imx_config {
  52         unsigned int speed_hz;
  53         unsigned int bpw;
  54         unsigned int mode;
  55         int cs;
  56 };
  57
  58 struct spi_imx_data {
  59         struct spi_bitbang bitbang;
  60
  61         struct completion xfer_done;
  62         void *base;
  63         int irq;
  64         struct clk *clk;
  65         unsigned long spi_clk;
  66         int *chipselect;
  67
  68         unsigned int count;
  69         void (*tx)(struct spi_imx_data *);
  70         void (*rx)(struct spi_imx_data *);
  71         void *rx_buf;
  72         const void *tx_buf;
  73         unsigned int txfifo; /* number of words pushed in tx FIFO */
  74
  75         /* SoC specific functions */
  76         void (*intctrl)(struct spi_imx_data *, int);
  77         int (*config)(struct spi_imx_data *, struct spi_imx_config *);
  78         void (*trigger)(struct spi_imx_data *);
  79         int (*rx_available)(struct spi_imx_data *);
  80 };
  81
  82 #define MXC_SPI_BUF_RX(type)                                            \
  83 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)         \
  84 {                                                                       \
  85         unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);       \
  86                                                                         \
  87         if (spi_imx->rx_buf) {                                          \
  88                 *(type *)spi_imx->rx_buf = val;                         \
  89                 spi_imx->rx_buf += sizeof(type);                        \
  90         }                                                               \
  91 }
  92
  93 #define MXC_SPI_BUF_TX(type)                                            \
  94 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)         \
  95 {                                                                       \
  96         type val = 0;                                                   \
  97                                                                         \
  98         if (spi_imx->tx_buf) {                                          \
  99                 val = *(type *)spi_imx->tx_buf;                         \
 100                 spi_imx->tx_buf += sizeof(type);                        \
 101         }                                                               \
 102                                                                         \
 103         spi_imx->count -= sizeof(type);                                 \
 104                                                                         \
 105         writel(val, spi_imx->base + MXC_CSPITXDATA);                    \
 106 }
 107
 108 MXC_SPI_BUF_RX(u8)
 109 MXC_SPI_BUF_TX(u8)
 110 MXC_SPI_BUF_RX(u16)
 111 MXC_SPI_BUF_TX(u16)
 112 MXC_SPI_BUF_RX(u32)
 113 MXC_SPI_BUF_TX(u32)
 114
 115 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
 116  * (which is currently not the case in this driver)
 117  */
 118 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
 119         256, 384, 512, 768, 1024};
 120
 121 /* MX21, MX27 */
 122 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
 123                 unsigned int fspi)
 124 {
 125         int i, max;
 126
 127         if (cpu_is_mx21())
 128                 max = 18;
 129         else
 130                 max = 16;
 131
 132         for (i = 2; i < max; i++)
 133                 if (fspi * mxc_clkdivs[i] >= fin)
 134                         return i;
 135
 136         return max;
 137 }
 138
 139 /* MX1, MX31, MX35 */
 140 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
 141                 unsigned int fspi)
 142 {
 143         int i, div = 4;
 144
 145         for (i = 0; i < 7; i++) {
 146                 if (fspi * div >= fin)
 147                         return i;
 148                 div <<= 1;
 149         }
 150
 151         return 7;
 152 }
 153
 154 #define MX31_INTREG_TEEN        (1 << 0)
 155 #define MX31_INTREG_RREN        (1 << 3)
 156
 157 #define MX31_CSPICTRL_ENABLE    (1 << 0)
 158 #define MX31_CSPICTRL_MASTER    (1 << 1)
 159 #define MX31_CSPICTRL_XCH       (1 << 2)
 160 #define MX31_CSPICTRL_POL       (1 << 4)
 161 #define MX31_CSPICTRL_PHA       (1 << 5)
 162 #define MX31_CSPICTRL_SSCTL     (1 << 6)
 163 #define MX31_CSPICTRL_SSPOL     (1 << 7)
 164 #define MX31_CSPICTRL_BC_SHIFT  8
 165 #define MX35_CSPICTRL_BL_SHIFT  20
 166 #define MX31_CSPICTRL_CS_SHIFT  24
 167 #define MX35_CSPICTRL_CS_SHIFT  12
 168 #define MX31_CSPICTRL_DR_SHIFT  16
 169
 170 #define MX31_CSPISTATUS         0x14
 171 #define MX31_STATUS_RR          (1 << 3)
 172
 173 /* These functions also work for the i.MX35, but be aware that
 174  * the i.MX35 has a slightly different register layout for bits
 175  * we do not use here.
 176  */
 177 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
 178 {
 179         unsigned int val = 0;
 180
 181         if (enable & MXC_INT_TE)
 182                 val |= MX31_INTREG_TEEN;
 183         if (enable & MXC_INT_RR)
 184                 val |= MX31_INTREG_RREN;
 185
 186         writel(val, spi_imx->base + MXC_CSPIINT);
 187 }
 188
 189 static void mx31_trigger(struct spi_imx_data *spi_imx)
 190 {
 191         unsigned int reg;
 192
 193         reg = readl(spi_imx->base + MXC_CSPICTRL);
 194         reg |= MX31_CSPICTRL_XCH;
 195         writel(reg, spi_imx->base + MXC_CSPICTRL);
 196 }
 197
 198 static int mx31_config(struct spi_imx_data *spi_imx,
 199                 struct spi_imx_config *config)
 200 {
 201         unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
 202
 203         reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 204                 MX31_CSPICTRL_DR_SHIFT;
 205
 206         if (cpu_is_mx31())
 207                 reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
 208         else if (cpu_is_mx35()) {
 209                 reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
 210                 reg |= MX31_CSPICTRL_SSCTL;
 211         }
 212
 213         if (config->mode & SPI_CPHA)
 214                 reg |= MX31_CSPICTRL_PHA;
 215         if (config->mode & SPI_CPOL)
 216                 reg |= MX31_CSPICTRL_POL;
 217         if (config->mode & SPI_CS_HIGH)
 218                 reg |= MX31_CSPICTRL_SSPOL;
 219         if (config->cs < 0) {
 220                 if (cpu_is_mx31())
 221                         reg |= (config->cs + 32) << MX31_CSPICTRL_CS_SHIFT;
 222                 else if (cpu_is_mx35())
 223                         reg |= (config->cs + 32) << MX35_CSPICTRL_CS_SHIFT;
 224         }
 225
 226         writel(reg, spi_imx->base + MXC_CSPICTRL);
 227
 228         return 0;
 229 }
 230
 231 static int mx31_rx_available(struct spi_imx_data *spi_imx)
 232 {
 233         return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
 234 }
 235
 236 #define MX27_INTREG_RR          (1 << 4)
 237 #define MX27_INTREG_TEEN        (1 << 9)
 238 #define MX27_INTREG_RREN        (1 << 13)
 239
 240 #define MX27_CSPICTRL_POL       (1 << 5)
 241 #define MX27_CSPICTRL_PHA       (1 << 6)
 242 #define MX27_CSPICTRL_SSPOL     (1 << 8)
 243 #define MX27_CSPICTRL_XCH       (1 << 9)
 244 #define MX27_CSPICTRL_ENABLE    (1 << 10)
 245 #define MX27_CSPICTRL_MASTER    (1 << 11)
 246 #define MX27_CSPICTRL_DR_SHIFT  14
 247 #define MX27_CSPICTRL_CS_SHIFT  19
 248
 249 static void mx27_intctrl(struct spi_imx_data *spi_imx, int enable)
 250 {
 251         unsigned int val = 0;
 252
 253         if (enable & MXC_INT_TE)
 254                 val |= MX27_INTREG_TEEN;
 255         if (enable & MXC_INT_RR)
 256                 val |= MX27_INTREG_RREN;
 257
 258         writel(val, spi_imx->base + MXC_CSPIINT);
 259 }
 260
 261 static void mx27_trigger(struct spi_imx_data *spi_imx)
 262 {
 263         unsigned int reg;
 264
 265         reg = readl(spi_imx->base + MXC_CSPICTRL);
 266         reg |= MX27_CSPICTRL_XCH;
 267         writel(reg, spi_imx->base + MXC_CSPICTRL);
 268 }
 269
 270 static int mx27_config(struct spi_imx_data *spi_imx,
 271                 struct spi_imx_config *config)
 272 {
 273         unsigned int reg = MX27_CSPICTRL_ENABLE | MX27_CSPICTRL_MASTER;
 274
 275         reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz) <<
 276                 MX27_CSPICTRL_DR_SHIFT;
 277         reg |= config->bpw - 1;
 278
 279         if (config->mode & SPI_CPHA)
 280                 reg |= MX27_CSPICTRL_PHA;
 281         if (config->mode & SPI_CPOL)
 282                 reg |= MX27_CSPICTRL_POL;
 283         if (config->mode & SPI_CS_HIGH)
 284                 reg |= MX27_CSPICTRL_SSPOL;
 285         if (config->cs < 0)
 286                 reg |= (config->cs + 32) << MX27_CSPICTRL_CS_SHIFT;
 287
 288         writel(reg, spi_imx->base + MXC_CSPICTRL);
 289
 290         return 0;
 291 }
 292
 293 static int mx27_rx_available(struct spi_imx_data *spi_imx)
 294 {
 295         return readl(spi_imx->base + MXC_CSPIINT) & MX27_INTREG_RR;
 296 }
 297
 298 #define MX1_INTREG_RR           (1 << 3)
 299 #define MX1_INTREG_TEEN         (1 << 8)
 300 #define MX1_INTREG_RREN         (1 << 11)
 301
 302 #define MX1_CSPICTRL_POL        (1 << 4)
 303 #define MX1_CSPICTRL_PHA        (1 << 5)
 304 #define MX1_CSPICTRL_XCH        (1 << 8)
 305 #define MX1_CSPICTRL_ENABLE     (1 << 9)
 306 #define MX1_CSPICTRL_MASTER     (1 << 10)
 307 #define MX1_CSPICTRL_DR_SHIFT   13
 308
 309 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
 310 {
 311         unsigned int val = 0;
 312
 313         if (enable & MXC_INT_TE)
 314                 val |= MX1_INTREG_TEEN;
 315         if (enable & MXC_INT_RR)
 316                 val |= MX1_INTREG_RREN;
 317
 318         writel(val, spi_imx->base + MXC_CSPIINT);
 319 }
 320
 321 static void mx1_trigger(struct spi_imx_data *spi_imx)
 322 {
 323         unsigned int reg;
 324
 325         reg = readl(spi_imx->base + MXC_CSPICTRL);
 326         reg |= MX1_CSPICTRL_XCH;
 327         writel(reg, spi_imx->base + MXC_CSPICTRL);
 328 }
 329
 330 static int mx1_config(struct spi_imx_data *spi_imx,
 331                 struct spi_imx_config *config)
 332 {
 333         unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
 334
 335         reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
 336                 MX1_CSPICTRL_DR_SHIFT;
 337         reg |= config->bpw - 1;
 338
 339         if (config->mode & SPI_CPHA)
 340                 reg |= MX1_CSPICTRL_PHA;
 341         if (config->mode & SPI_CPOL)
 342                 reg |= MX1_CSPICTRL_POL;
 343
 344         writel(reg, spi_imx->base + MXC_CSPICTRL);
 345
 346         return 0;
 347 }
 348
 349 static int mx1_rx_available(struct spi_imx_data *spi_imx)
 350 {
 351         return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
 352 }
 353
 354 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 355 {
 356         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 357         int gpio = spi_imx->chipselect[spi->chip_select];
 358         int active = is_active != BITBANG_CS_INACTIVE;
 359         int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
 360
 361         if (gpio < 0)
 362                 return;
 363
 364         gpio_set_value(gpio, dev_is_lowactive ^ active);
 365 }
 366
 367 static void spi_imx_push(struct spi_imx_data *spi_imx)
 368 {
 369         while (spi_imx->txfifo < 8) {
 370                 if (!spi_imx->count)
 371                         break;
 372                 spi_imx->tx(spi_imx);
 373                 spi_imx->txfifo++;
 374         }
 375
 376         spi_imx->trigger(spi_imx);
 377 }
 378
 379 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
 380 {
 381         struct spi_imx_data *spi_imx = dev_id;
 382
 383         while (spi_imx->rx_available(spi_imx)) {
 384                 spi_imx->rx(spi_imx);
 385                 spi_imx->txfifo--;
 386         }
 387
 388         if (spi_imx->count) {
 389                 spi_imx_push(spi_imx);
 390                 return IRQ_HANDLED;
 391         }
 392
 393         if (spi_imx->txfifo) {
 394                 /* No data left to push, but still waiting for rx data,
 395                  * enable receive data available interrupt.
 396                  */
 397                 spi_imx->intctrl(spi_imx, MXC_INT_RR);
 398                 return IRQ_HANDLED;
 399         }
 400
 401         spi_imx->intctrl(spi_imx, 0);
 402         complete(&spi_imx->xfer_done);
 403
 404         return IRQ_HANDLED;
 405 }
 406
 407 static int spi_imx_setupxfer(struct spi_device *spi,
 408                                  struct spi_transfer *t)
 409 {
 410         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 411         struct spi_imx_config config;
 412
 413         config.bpw = t ? t->bits_per_word : spi->bits_per_word;
 414         config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
 415         config.mode = spi->mode;
 416         config.cs = spi_imx->chipselect[spi->chip_select];
 417
 418         if (!config.speed_hz)
 419                 config.speed_hz = spi->max_speed_hz;
 420         if (!config.bpw)
 421                 config.bpw = spi->bits_per_word;
 422         if (!config.speed_hz)
 423                 config.speed_hz = spi->max_speed_hz;
 424
 425         /* Initialize the functions for transfer */
 426         if (config.bpw <= 8) {
 427                 spi_imx->rx = spi_imx_buf_rx_u8;
 428                 spi_imx->tx = spi_imx_buf_tx_u8;
 429         } else if (config.bpw <= 16) {
 430                 spi_imx->rx = spi_imx_buf_rx_u16;
 431                 spi_imx->tx = spi_imx_buf_tx_u16;
 432         } else if (config.bpw <= 32) {
 433                 spi_imx->rx = spi_imx_buf_rx_u32;
 434                 spi_imx->tx = spi_imx_buf_tx_u32;
 435         } else
 436                 BUG();
 437
 438         spi_imx->config(spi_imx, &config);
 439
 440         return 0;
 441 }
 442
 443 static int spi_imx_transfer(struct spi_device *spi,
 444                                 struct spi_transfer *transfer)
 445 {
 446         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 447
 448         spi_imx->tx_buf = transfer->tx_buf;
 449         spi_imx->rx_buf = transfer->rx_buf;
 450         spi_imx->count = transfer->len;
 451         spi_imx->txfifo = 0;
 452
 453         init_completion(&spi_imx->xfer_done);
 454
 455         spi_imx_push(spi_imx);
 456
 457         spi_imx->intctrl(spi_imx, MXC_INT_TE);
 458
 459         wait_for_completion(&spi_imx->xfer_done);
 460
 461         return transfer->len;
 462 }
 463
 464 static int spi_imx_setup(struct spi_device *spi)
 465 {
 466         struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 467         int gpio = spi_imx->chipselect[spi->chip_select];
 468
 469         pr_debug("%s: mode %d, %u bpw, %d hz\n", __func__,
 470                  spi->mode, spi->bits_per_word, spi->max_speed_hz);
 471
 472         if (gpio >= 0)
 473                 gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
 474
 475         spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
 476
 477         return 0;
 478 }
 479
 480 static void spi_imx_cleanup(struct spi_device *spi)
 481 {
 482 }
 483
 484 static int __init spi_imx_probe(struct platform_device *pdev)
 485 {
 486         struct spi_imx_master *mxc_platform_info;
 487         struct spi_master *master;
 488         struct spi_imx_data *spi_imx;
 489         struct resource *res;
 490         int i, ret;
 491
 492         mxc_platform_info = (struct spi_imx_master *)pdev->dev.platform_data;
 493         if (!mxc_platform_info) {
 494                 dev_err(&pdev->dev, "can't get the platform data\n");
 495                 return -EINVAL;
 496         }
 497
 498         master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data));
 499         if (!master)
 500                 return -ENOMEM;
 501
 502         platform_set_drvdata(pdev, master);
 503
 504         master->bus_num = pdev->id;
 505         master->num_chipselect = mxc_platform_info->num_chipselect;
 506
 507         spi_imx = spi_master_get_devdata(master);
 508         spi_imx->bitbang.master = spi_master_get(master);
 509         spi_imx->chipselect = mxc_platform_info->chipselect;
 510
 511         for (i = 0; i < master->num_chipselect; i++) {
 512                 if (spi_imx->chipselect[i] < 0)
 513                         continue;
 514                 ret = gpio_request(spi_imx->chipselect[i], DRIVER_NAME);
 515                 if (ret) {
 516                         i--;
 517                         while (i > 0)
 518                                 if (spi_imx->chipselect[i] >= 0)
 519                                         gpio_free(spi_imx->chipselect[i--]);
 520                         dev_err(&pdev->dev, "can't get cs gpios");
 521                         goto out_master_put;
 522                 }
 523         }
 524
 525         spi_imx->bitbang.chipselect = spi_imx_chipselect;
 526         spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
 527         spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
 528         spi_imx->bitbang.master->setup = spi_imx_setup;
 529         spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
 530         spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 531
 532         init_completion(&spi_imx->xfer_done);
 533
 534         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 535         if (!res) {
 536                 dev_err(&pdev->dev, "can't get platform resource\n");
 537                 ret = -ENOMEM;
 538                 goto out_gpio_free;
 539         }
 540
 541         if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
 542                 dev_err(&pdev->dev, "request_mem_region failed\n");
 543                 ret = -EBUSY;
 544                 goto out_gpio_free;
 545         }
 546
 547         spi_imx->base = ioremap(res->start, resource_size(res));
 548         if (!spi_imx->base) {
 549                 ret = -EINVAL;
 550                 goto out_release_mem;
 551         }
 552
 553         spi_imx->irq = platform_get_irq(pdev, 0);
 554         if (!spi_imx->irq) {
 555                 ret = -EINVAL;
 556                 goto out_iounmap;
 557         }
 558
 559         ret = request_irq(spi_imx->irq, spi_imx_isr, 0, DRIVER_NAME, spi_imx);
 560         if (ret) {
 561                 dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret);
 562                 goto out_iounmap;
 563         }
 564
 565         if (cpu_is_mx31() || cpu_is_mx35()) {
 566                 spi_imx->intctrl = mx31_intctrl;
 567                 spi_imx->config = mx31_config;
 568                 spi_imx->trigger = mx31_trigger;
 569                 spi_imx->rx_available = mx31_rx_available;
 570         } else  if (cpu_is_mx27() || cpu_is_mx21()) {
 571                 spi_imx->intctrl = mx27_intctrl;
 572                 spi_imx->config = mx27_config;
 573                 spi_imx->trigger = mx27_trigger;
 574                 spi_imx->rx_available = mx27_rx_available;
 575         } else if (cpu_is_mx1()) {
 576                 spi_imx->intctrl = mx1_intctrl;
 577                 spi_imx->config = mx1_config;
 578                 spi_imx->trigger = mx1_trigger;
 579                 spi_imx->rx_available = mx1_rx_available;
 580         } else
 581                 BUG();
 582
 583         spi_imx->clk = clk_get(&pdev->dev, NULL);
 584         if (IS_ERR(spi_imx->clk)) {
 585                 dev_err(&pdev->dev, "unable to get clock\n");
 586                 ret = PTR_ERR(spi_imx->clk);
 587                 goto out_free_irq;
 588         }
 589
 590         clk_enable(spi_imx->clk);
 591         spi_imx->spi_clk = clk_get_rate(spi_imx->clk);
 592
 593         if (!cpu_is_mx31() || !cpu_is_mx35())
 594                 writel(1, spi_imx->base + MXC_RESET);
 595
 596         spi_imx->intctrl(spi_imx, 0);
 597
 598         ret = spi_bitbang_start(&spi_imx->bitbang);
 599         if (ret) {
 600                 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
 601                 goto out_clk_put;
 602         }
 603
 604         dev_info(&pdev->dev, "probed\n");
 605
 606         return ret;
 607
 608 out_clk_put:
 609         clk_disable(spi_imx->clk);
 610         clk_put(spi_imx->clk);
 611 out_free_irq:
 612         free_irq(spi_imx->irq, spi_imx);
 613 out_iounmap:
 614         iounmap(spi_imx->base);
 615 out_release_mem:
 616         release_mem_region(res->start, resource_size(res));
 617 out_gpio_free:
 618         for (i = 0; i < master->num_chipselect; i++)
 619                 if (spi_imx->chipselect[i] >= 0)
 620                         gpio_free(spi_imx->chipselect[i]);
 621 out_master_put:
 622         spi_master_put(master);
 623         kfree(master);
 624         platform_set_drvdata(pdev, NULL);
 625         return ret;
 626 }
 627
 628 static int __exit spi_imx_remove(struct platform_device *pdev)
 629 {
 630         struct spi_master *master = platform_get_drvdata(pdev);
 631         struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 632         struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
 633         int i;
 634
 635         spi_bitbang_stop(&spi_imx->bitbang);
 636
 637         writel(0, spi_imx->base + MXC_CSPICTRL);
 638         clk_disable(spi_imx->clk);
 639         clk_put(spi_imx->clk);
 640         free_irq(spi_imx->irq, spi_imx);
 641         iounmap(spi_imx->base);
 642
 643         for (i = 0; i < master->num_chipselect; i++)
 644                 if (spi_imx->chipselect[i] >= 0)
 645                         gpio_free(spi_imx->chipselect[i]);
 646
 647         spi_master_put(master);
 648
 649         release_mem_region(res->start, resource_size(res));
 650
 651         platform_set_drvdata(pdev, NULL);
 652
 653         return 0;
 654 }
 655
 656 static struct platform_driver spi_imx_driver = {
 657         .driver = {
 658                    .name = DRIVER_NAME,
 659                    .owner = THIS_MODULE,
 660                    },
 661         .probe = spi_imx_probe,
 662         .remove = __exit_p(spi_imx_remove),
 663 };
 664
 665 static int __init spi_imx_init(void)
 666 {
 667         return platform_driver_register(&spi_imx_driver);
 668 }
 669
 670 static void __exit spi_imx_exit(void)
 671 {
 672         platform_driver_unregister(&spi_imx_driver);
 673 }
 674
 675 module_init(spi_imx_init);
 676 module_exit(spi_imx_exit);
 677
 678 MODULE_DESCRIPTION("SPI Master Controller driver");
 679 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
 680 MODULE_LICENSE("GPL");