drivers/mmc/host/sdhci-tegra.c

   1 /*
   2  * Copyright (C) 2010 Google, Inc.
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/err.h>
  17 #include <linux/module.h>
  18 #include <linux/init.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/clk.h>
  21 #include <linux/io.h>
  22 #include <linux/of.h>
  23 #include <linux/of_device.h>
  24 #include <linux/mmc/card.h>
  25 #include <linux/mmc/host.h>
  26 #include <linux/mmc/mmc.h>
  27 #include <linux/mmc/slot-gpio.h>
  28 #include <linux/gpio/consumer.h>
  29
  30 #include "sdhci-pltfm.h"
  31
  32 /* Tegra SDHOST controller vendor register definitions */
  33 #define SDHCI_TEGRA_VENDOR_CLOCK_CTRL                   0x100
  34 #define SDHCI_CLOCK_CTRL_TAP_MASK                       0x00ff0000
  35 #define SDHCI_CLOCK_CTRL_TAP_SHIFT                      16
  36 #define SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE          BIT(5)
  37 #define SDHCI_CLOCK_CTRL_PADPIPE_CLKEN_OVERRIDE         BIT(3)
  38 #define SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE        BIT(2)
  39
  40 #define SDHCI_TEGRA_VENDOR_MISC_CTRL            0x120
  41 #define SDHCI_MISC_CTRL_ENABLE_SDR104           0x8
  42 #define SDHCI_MISC_CTRL_ENABLE_SDR50            0x10
  43 #define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300   0x20
  44 #define SDHCI_MISC_CTRL_ENABLE_DDR50            0x200
  45
  46 #define SDHCI_TEGRA_AUTO_CAL_CONFIG             0x1e4
  47 #define SDHCI_AUTO_CAL_START                    BIT(31)
  48 #define SDHCI_AUTO_CAL_ENABLE                   BIT(29)
  49
  50 #define NVQUIRK_FORCE_SDHCI_SPEC_200    BIT(0)
  51 #define NVQUIRK_ENABLE_BLOCK_GAP_DET    BIT(1)
  52 #define NVQUIRK_ENABLE_SDHCI_SPEC_300   BIT(2)
  53 #define NVQUIRK_ENABLE_SDR50            BIT(3)
  54 #define NVQUIRK_ENABLE_SDR104           BIT(4)
  55 #define NVQUIRK_ENABLE_DDR50            BIT(5)
  56 #define NVQUIRK_HAS_PADCALIB            BIT(6)
  57
  58 struct sdhci_tegra_soc_data {
  59         const struct sdhci_pltfm_data *pdata;
  60         u32 nvquirks;
  61 };
  62
  63 struct sdhci_tegra {
  64         const struct sdhci_tegra_soc_data *soc_data;
  65         struct gpio_desc *power_gpio;
  66         bool ddr_signaling;
  67         bool pad_calib_required;
  68 };
  69
  70 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
  71 {
  72         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  73         struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
  74         const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
  75
  76         if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
  77                         (reg == SDHCI_HOST_VERSION))) {
  78                 /* Erratum: Version register is invalid in HW. */
  79                 return SDHCI_SPEC_200;
  80         }
  81
  82         return readw(host->ioaddr + reg);
  83 }
  84
  85 static void tegra_sdhci_writew(struct sdhci_host *host, u16 val, int reg)
  86 {
  87         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  88
  89         switch (reg) {
  90         case SDHCI_TRANSFER_MODE:
  91                 /*
  92                  * Postpone this write, we must do it together with a
  93                  * command write that is down below.
  94                  */
  95                 pltfm_host->xfer_mode_shadow = val;
  96                 return;
  97         case SDHCI_COMMAND:
  98                 writel((val << 16) | pltfm_host->xfer_mode_shadow,
  99                         host->ioaddr + SDHCI_TRANSFER_MODE);
 100                 return;
 101         }
 102
 103         writew(val, host->ioaddr + reg);
 104 }
 105
 106 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
 107 {
 108         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 109         struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
 110         const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
 111
 112         /* Seems like we're getting spurious timeout and crc errors, so
 113          * disable signalling of them. In case of real errors software
 114          * timers should take care of eventually detecting them.
 115          */
 116         if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
 117                 val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
 118
 119         writel(val, host->ioaddr + reg);
 120
 121         if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
 122                         (reg == SDHCI_INT_ENABLE))) {
 123                 /* Erratum: Must enable block gap interrupt detection */
 124                 u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
 125                 if (val & SDHCI_INT_CARD_INT)
 126                         gap_ctrl |= 0x8;
 127                 else
 128                         gap_ctrl &= ~0x8;
 129                 writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
 130         }
 131 }
 132
 133 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
 134 {
 135         return mmc_gpio_get_ro(host->mmc);
 136 }
 137
 138 static void tegra_sdhci_reset(struct sdhci_host *host, u8 mask)
 139 {
 140         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 141         struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
 142         const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
 143         u32 misc_ctrl, clk_ctrl;
 144
 145         sdhci_reset(host, mask);
 146
 147         if (!(mask & SDHCI_RESET_ALL))
 148                 return;
 149
 150         misc_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
 151         /* Erratum: Enable SDHCI spec v3.00 support */
 152         if (soc_data->nvquirks & NVQUIRK_ENABLE_SDHCI_SPEC_300)
 153                 misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300;
 154         /* Advertise UHS modes as supported by host */
 155         if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR50)
 156                 misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR50;
 157         else
 158                 misc_ctrl &= ~SDHCI_MISC_CTRL_ENABLE_SDR50;
 159         if (soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
 160                 misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_DDR50;
 161         else
 162                 misc_ctrl &= ~SDHCI_MISC_CTRL_ENABLE_DDR50;
 163         if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR104)
 164                 misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR104;
 165         else
 166                 misc_ctrl &= ~SDHCI_MISC_CTRL_ENABLE_SDR104;
 167         sdhci_writel(host, misc_ctrl, SDHCI_TEGRA_VENDOR_MISC_CTRL);
 168
 169         clk_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
 170         clk_ctrl &= ~SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE;
 171         if (soc_data->nvquirks & SDHCI_MISC_CTRL_ENABLE_SDR50)
 172                 clk_ctrl |= SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE;
 173         sdhci_writel(host, clk_ctrl, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
 174
 175         if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB)
 176                 tegra_host->pad_calib_required = true;
 177
 178         tegra_host->ddr_signaling = false;
 179 }
 180
 181 static void tegra_sdhci_set_bus_width(struct sdhci_host *host, int bus_width)
 182 {
 183         u32 ctrl;
 184
 185         ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
 186         if ((host->mmc->caps & MMC_CAP_8_BIT_DATA) &&
 187             (bus_width == MMC_BUS_WIDTH_8)) {
 188                 ctrl &= ~SDHCI_CTRL_4BITBUS;
 189                 ctrl |= SDHCI_CTRL_8BITBUS;
 190         } else {
 191                 ctrl &= ~SDHCI_CTRL_8BITBUS;
 192                 if (bus_width == MMC_BUS_WIDTH_4)
 193                         ctrl |= SDHCI_CTRL_4BITBUS;
 194                 else
 195                         ctrl &= ~SDHCI_CTRL_4BITBUS;
 196         }
 197         sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 198 }
 199
 200 static void tegra_sdhci_pad_autocalib(struct sdhci_host *host)
 201 {
 202         u32 val;
 203
 204         mdelay(1);
 205
 206         val = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
 207         val |= SDHCI_AUTO_CAL_ENABLE | SDHCI_AUTO_CAL_START;
 208         sdhci_writel(host,val, SDHCI_TEGRA_AUTO_CAL_CONFIG);
 209 }
 210
 211 static void tegra_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
 212 {
 213         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 214         struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
 215         unsigned long host_clk;
 216
 217         if (!clock)
 218                 return sdhci_set_clock(host, clock);
 219
 220         host_clk = tegra_host->ddr_signaling ? clock * 2 : clock;
 221         clk_set_rate(pltfm_host->clk, host_clk);
 222         host->max_clk = clk_get_rate(pltfm_host->clk);
 223
 224         sdhci_set_clock(host, clock);
 225
 226         if (tegra_host->pad_calib_required) {
 227                 tegra_sdhci_pad_autocalib(host);
 228                 tegra_host->pad_calib_required = false;
 229         }
 230 }
 231
 232 static void tegra_sdhci_set_uhs_signaling(struct sdhci_host *host,
 233                                           unsigned timing)
 234 {
 235         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 236         struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
 237
 238         if (timing == MMC_TIMING_UHS_DDR50)
 239                 tegra_host->ddr_signaling = true;
 240
 241         return sdhci_set_uhs_signaling(host, timing);
 242 }
 243
 244 static unsigned int tegra_sdhci_get_max_clock(struct sdhci_host *host)
 245 {
 246         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 247
 248         /*
 249          * DDR modes require the host to run at double the card frequency, so
 250          * the maximum rate we can support is half of the module input clock.
 251          */
 252         return clk_round_rate(pltfm_host->clk, UINT_MAX) / 2;
 253 }
 254
 255 static void tegra_sdhci_set_tap(struct sdhci_host *host, unsigned int tap)
 256 {
 257         u32 reg;
 258
 259         reg = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
 260         reg &= ~SDHCI_CLOCK_CTRL_TAP_MASK;
 261         reg |= tap << SDHCI_CLOCK_CTRL_TAP_SHIFT;
 262         sdhci_writel(host, reg, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
 263 }
 264
 265 static int tegra_sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
 266 {
 267         unsigned int min, max;
 268
 269         /*
 270          * Start search for minimum tap value at 10, as smaller values are
 271          * may wrongly be reported as working but fail at higher speeds,
 272          * according to the TRM.
 273          */
 274         min = 10;
 275         while (min < 255) {
 276                 tegra_sdhci_set_tap(host, min);
 277                 if (!mmc_send_tuning(host->mmc, opcode, NULL))
 278                         break;
 279                 min++;
 280         }
 281
 282         /* Find the maximum tap value that still passes. */
 283         max = min + 1;
 284         while (max < 255) {
 285                 tegra_sdhci_set_tap(host, max);
 286                 if (mmc_send_tuning(host->mmc, opcode, NULL)) {
 287                         max--;
 288                         break;
 289                 }
 290                 max++;
 291         }
 292
 293         /* The TRM states the ideal tap value is at 75% in the passing range. */
 294         tegra_sdhci_set_tap(host, min + ((max - min) * 3 / 4));
 295
 296         return mmc_send_tuning(host->mmc, opcode, NULL);
 297 }
 298
 299 static void tegra_sdhci_voltage_switch(struct sdhci_host *host)
 300 {
 301         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 302         struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
 303         const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
 304
 305         if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB)
 306                 tegra_host->pad_calib_required = true;
 307 }
 308
 309 static const struct sdhci_ops tegra_sdhci_ops = {
 310         .get_ro     = tegra_sdhci_get_ro,
 311         .read_w     = tegra_sdhci_readw,
 312         .write_l    = tegra_sdhci_writel,
 313         .set_clock  = tegra_sdhci_set_clock,
 314         .set_bus_width = tegra_sdhci_set_bus_width,
 315         .reset      = tegra_sdhci_reset,
 316         .platform_execute_tuning = tegra_sdhci_execute_tuning,
 317         .set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
 318         .voltage_switch = tegra_sdhci_voltage_switch,
 319         .get_max_clock = tegra_sdhci_get_max_clock,
 320 };
 321
 322 static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
 323         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 324                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 325                   SDHCI_QUIRK_NO_HISPD_BIT |
 326                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
 327                   SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
 328         .ops  = &tegra_sdhci_ops,
 329 };
 330
 331 static const struct sdhci_tegra_soc_data soc_data_tegra20 = {
 332         .pdata = &sdhci_tegra20_pdata,
 333         .nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
 334                     NVQUIRK_ENABLE_BLOCK_GAP_DET,
 335 };
 336
 337 static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
 338         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 339                   SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 340                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 341                   SDHCI_QUIRK_NO_HISPD_BIT |
 342                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
 343                   SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
 344         .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
 345         .ops  = &tegra_sdhci_ops,
 346 };
 347
 348 static const struct sdhci_tegra_soc_data soc_data_tegra30 = {
 349         .pdata = &sdhci_tegra30_pdata,
 350         .nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300 |
 351                     NVQUIRK_ENABLE_SDR50 |
 352                     NVQUIRK_ENABLE_SDR104 |
 353                     NVQUIRK_HAS_PADCALIB,
 354 };
 355
 356 static const struct sdhci_ops tegra114_sdhci_ops = {
 357         .get_ro     = tegra_sdhci_get_ro,
 358         .read_w     = tegra_sdhci_readw,
 359         .write_w    = tegra_sdhci_writew,
 360         .write_l    = tegra_sdhci_writel,
 361         .set_clock  = tegra_sdhci_set_clock,
 362         .set_bus_width = tegra_sdhci_set_bus_width,
 363         .reset      = tegra_sdhci_reset,
 364         .platform_execute_tuning = tegra_sdhci_execute_tuning,
 365         .set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
 366         .voltage_switch = tegra_sdhci_voltage_switch,
 367         .get_max_clock = tegra_sdhci_get_max_clock,
 368 };
 369
 370 static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
 371         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 372                   SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 373                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 374                   SDHCI_QUIRK_NO_HISPD_BIT |
 375                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
 376                   SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
 377         .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
 378         .ops  = &tegra114_sdhci_ops,
 379 };
 380
 381 static const struct sdhci_tegra_soc_data soc_data_tegra114 = {
 382         .pdata = &sdhci_tegra114_pdata,
 383 };
 384
 385 static const struct sdhci_tegra_soc_data soc_data_tegra124 = {
 386         .pdata = &sdhci_tegra114_pdata,
 387         .nvquirks = NVQUIRK_ENABLE_SDR50 |
 388                     NVQUIRK_ENABLE_DDR50 |
 389                     NVQUIRK_ENABLE_SDR104 |
 390                     NVQUIRK_HAS_PADCALIB,
 391 };
 392
 393 static const struct sdhci_pltfm_data sdhci_tegra210_pdata = {
 394         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 395                   SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 396                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 397                   SDHCI_QUIRK_NO_HISPD_BIT |
 398                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
 399                   SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
 400         .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
 401         .ops  = &tegra114_sdhci_ops,
 402 };
 403
 404 static const struct sdhci_tegra_soc_data soc_data_tegra210 = {
 405         .pdata = &sdhci_tegra210_pdata,
 406 };
 407
 408 static const struct of_device_id sdhci_tegra_dt_match[] = {
 409         { .compatible = "nvidia,tegra210-sdhci", .data = &soc_data_tegra210 },
 410         { .compatible = "nvidia,tegra124-sdhci", .data = &soc_data_tegra124 },
 411         { .compatible = "nvidia,tegra114-sdhci", .data = &soc_data_tegra114 },
 412         { .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
 413         { .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
 414         {}
 415 };
 416 MODULE_DEVICE_TABLE(of, sdhci_tegra_dt_match);
 417
 418 static int sdhci_tegra_probe(struct platform_device *pdev)
 419 {
 420         const struct of_device_id *match;
 421         const struct sdhci_tegra_soc_data *soc_data;
 422         struct sdhci_host *host;
 423         struct sdhci_pltfm_host *pltfm_host;
 424         struct sdhci_tegra *tegra_host;
 425         struct clk *clk;
 426         int rc;
 427
 428         match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
 429         if (!match)
 430                 return -EINVAL;
 431         soc_data = match->data;
 432
 433         host = sdhci_pltfm_init(pdev, soc_data->pdata, sizeof(*tegra_host));
 434         if (IS_ERR(host))
 435                 return PTR_ERR(host);
 436         pltfm_host = sdhci_priv(host);
 437
 438         tegra_host = sdhci_pltfm_priv(pltfm_host);
 439         tegra_host->ddr_signaling = false;
 440         tegra_host->pad_calib_required = false;
 441         tegra_host->soc_data = soc_data;
 442
 443         rc = mmc_of_parse(host->mmc);
 444         if (rc)
 445                 goto err_parse_dt;
 446
 447         if (tegra_host->soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
 448                 host->mmc->caps |= MMC_CAP_1_8V_DDR;
 449
 450         tegra_host->power_gpio = devm_gpiod_get_optional(&pdev->dev, "power",
 451                                                          GPIOD_OUT_HIGH);
 452         if (IS_ERR(tegra_host->power_gpio)) {
 453                 rc = PTR_ERR(tegra_host->power_gpio);
 454                 goto err_power_req;
 455         }
 456
 457         clk = devm_clk_get(mmc_dev(host->mmc), NULL);
 458         if (IS_ERR(clk)) {
 459                 dev_err(mmc_dev(host->mmc), "clk err\n");
 460                 rc = PTR_ERR(clk);
 461                 goto err_clk_get;
 462         }
 463         clk_prepare_enable(clk);
 464         pltfm_host->clk = clk;
 465
 466         rc = sdhci_add_host(host);
 467         if (rc)
 468                 goto err_add_host;
 469
 470         return 0;
 471
 472 err_add_host:
 473         clk_disable_unprepare(pltfm_host->clk);
 474 err_clk_get:
 475 err_power_req:
 476 err_parse_dt:
 477         sdhci_pltfm_free(pdev);
 478         return rc;
 479 }
 480
 481 static struct platform_driver sdhci_tegra_driver = {
 482         .driver         = {
 483                 .name   = "sdhci-tegra",
 484                 .of_match_table = sdhci_tegra_dt_match,
 485                 .pm     = SDHCI_PLTFM_PMOPS,
 486         },
 487         .probe          = sdhci_tegra_probe,
 488         .remove         = sdhci_pltfm_unregister,
 489 };
 490
 491 module_platform_driver(sdhci_tegra_driver);
 492
 493 MODULE_DESCRIPTION("SDHCI driver for Tegra");
 494 MODULE_AUTHOR("Google, Inc.");
 495 MODULE_LICENSE("GPL v2");