package/kernel/gpio-nct5104d/src/gpio-nct5104d.c

   1 /*
   2  * GPIO driver for NCT5104D
   3  *
   4  * Author: Tasanakorn Phaipool <tasanakorn@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/io.h>
  16 #include <linux/gpio.h>
  17 #include <linux/version.h>
  18 #include <linux/dmi.h>
  19 #include <linux/string.h>
  20
  21 #define DRVNAME "gpio-nct5104d"
  22
  23 /*
  24  * Super-I/O registers
  25  */
  26 #define SIO_LDSEL               0x07    /* Logical device select */
  27 #define SIO_CHIPID              0x20    /* Chaip ID (2 bytes) */
  28 #define SIO_GPIO_ENABLE 0x30    /* GPIO enable */
  29 #define SIO_GPIO1_MODE          0xE0    /* GPIO1 Mode OpenDrain/Push-Pull */
  30 #define SIO_GPIO2_MODE          0xE1    /* GPIO2 Mode OpenDrain/Push-Pull */
  31
  32 #define SIO_LD_GPIO             0x07    /* GPIO logical device */
  33 #define SIO_LD_GPIO_MODE        0x0F    /* GPIO mode control device */
  34 #define SIO_UNLOCK_KEY          0x87    /* Key to enable Super-I/O */
  35 #define SIO_LOCK_KEY            0xAA    /* Key to disable Super-I/O */
  36
  37 #define SIO_NCT5104D_ID                                 0x1061  /* Chip ID */
  38 #define SIO_PCENGINES_APU_NCT5104D_ID1  0xc452  /* Chip ID */
  39 #define SIO_PCENGINES_APU_NCT5104D_ID2  0xc453  /* Chip ID */
  40
  41 enum chips { nct5104d };
  42
  43 static const char * const nct5104d_names[] = {
  44         "nct5104d"
  45 };
  46
  47 struct nct5104d_sio {
  48         int addr;
  49         enum chips type;
  50 };
  51
  52 struct nct5104d_gpio_bank {
  53         struct gpio_chip chip;
  54         unsigned int regbase;
  55         struct nct5104d_gpio_data *data;
  56 };
  57
  58 struct nct5104d_gpio_data {
  59         struct nct5104d_sio *sio;
  60         int nr_bank;
  61         struct nct5104d_gpio_bank *bank;
  62 };
  63
  64 /*
  65  * Super-I/O functions.
  66  */
  67
  68 static inline int superio_inb(int base, int reg)
  69 {
  70         outb(reg, base);
  71         return inb(base + 1);
  72 }
  73
  74 static int superio_inw(int base, int reg)
  75 {
  76         int val;
  77
  78         outb(reg++, base);
  79         val = inb(base + 1) << 8;
  80         outb(reg, base);
  81         val |= inb(base + 1);
  82
  83         return val;
  84 }
  85
  86 static inline void superio_outb(int base, int reg, int val)
  87 {
  88         outb(reg, base);
  89         outb(val, base + 1);
  90 }
  91
  92 static inline int superio_enter(int base)
  93 {
  94         /* Don't step on other drivers' I/O space by accident. */
  95         if (!request_muxed_region(base, 2, DRVNAME)) {
  96                 pr_err(DRVNAME "I/O address 0x%04x already in use\n", base);
  97                 return -EBUSY;
  98         }
  99
 100         /* According to the datasheet the key must be send twice. */
 101         outb(SIO_UNLOCK_KEY, base);
 102         outb(SIO_UNLOCK_KEY, base);
 103
 104         return 0;
 105 }
 106
 107 static inline void superio_select(int base, int ld)
 108 {
 109         outb(SIO_LDSEL, base);
 110         outb(ld, base + 1);
 111 }
 112
 113 static inline void superio_exit(int base)
 114 {
 115         outb(SIO_LOCK_KEY, base);
 116         release_region(base, 2);
 117 }
 118
 119 /*
 120  * GPIO chip.
 121  */
 122
 123 static int nct5104d_gpio_direction_in(struct gpio_chip *chip, unsigned offset);
 124 static int nct5104d_gpio_get(struct gpio_chip *chip, unsigned offset);
 125 static int nct5104d_gpio_direction_out(struct gpio_chip *chip,
 126                                      unsigned offset, int value);
 127 static void nct5104d_gpio_set(struct gpio_chip *chip, unsigned offset, int value);
 128
 129 #define NCT5104D_GPIO_BANK(_base, _ngpio, _regbase)                     \
 130         {                                                               \
 131                 .chip = {                                               \
 132                         .label            = DRVNAME,                    \
 133                         .owner            = THIS_MODULE,                \
 134                         .direction_input  = nct5104d_gpio_direction_in, \
 135                         .get              = nct5104d_gpio_get,          \
 136                         .direction_output = nct5104d_gpio_direction_out,        \
 137                         .set              = nct5104d_gpio_set,          \
 138                         .base             = _base,                      \
 139                         .ngpio            = _ngpio,                     \
 140                         .can_sleep        = true,                       \
 141                 },                                                      \
 142                 .regbase = _regbase,                                    \
 143         }
 144
 145 #define gpio_dir(base) (base + 0)
 146 #define gpio_data(base) (base + 1)
 147
 148 static struct nct5104d_gpio_bank nct5104d_gpio_bank[] = {
 149         NCT5104D_GPIO_BANK(0 , 8, 0xE0),
 150         NCT5104D_GPIO_BANK(10, 8, 0xE4)
 151 };
 152
 153 static int nct5104d_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 154 {
 155         int err;
 156         struct nct5104d_gpio_bank *bank =
 157                 container_of(chip, struct nct5104d_gpio_bank, chip);
 158         struct nct5104d_sio *sio = bank->data->sio;
 159         u8 dir;
 160
 161         err = superio_enter(sio->addr);
 162         if (err)
 163                 return err;
 164         superio_select(sio->addr, SIO_LD_GPIO);
 165
 166         dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
 167         dir |= (1 << offset);
 168         superio_outb(sio->addr, gpio_dir(bank->regbase), dir);
 169
 170         superio_exit(sio->addr);
 171
 172         return 0;
 173 }
 174
 175 static int nct5104d_gpio_get(struct gpio_chip *chip, unsigned offset)
 176 {
 177         int err;
 178         struct nct5104d_gpio_bank *bank =
 179                 container_of(chip, struct nct5104d_gpio_bank, chip);
 180         struct nct5104d_sio *sio = bank->data->sio;
 181         u8 data;
 182
 183         err = superio_enter(sio->addr);
 184         if (err)
 185                 return err;
 186         superio_select(sio->addr, SIO_LD_GPIO);
 187
 188         data = superio_inb(sio->addr, gpio_data(bank->regbase));
 189
 190         superio_exit(sio->addr);
 191
 192         return !!(data & 1 << offset);
 193 }
 194
 195 static int nct5104d_gpio_direction_out(struct gpio_chip *chip,
 196                                      unsigned offset, int value)
 197 {
 198         int err;
 199         struct nct5104d_gpio_bank *bank =
 200                 container_of(chip, struct nct5104d_gpio_bank, chip);
 201         struct nct5104d_sio *sio = bank->data->sio;
 202         u8 dir, data_out;
 203
 204         err = superio_enter(sio->addr);
 205         if (err)
 206                 return err;
 207         superio_select(sio->addr, SIO_LD_GPIO);
 208
 209         data_out = superio_inb(sio->addr, gpio_data(bank->regbase));
 210         if (value)
 211                 data_out |= (1 << offset);
 212         else
 213                 data_out &= ~(1 << offset);
 214         superio_outb(sio->addr, gpio_data(bank->regbase), data_out);
 215
 216         dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
 217         dir &= ~(1 << offset);
 218         superio_outb(sio->addr, gpio_dir(bank->regbase), dir);
 219
 220         superio_exit(sio->addr);
 221
 222         return 0;
 223 }
 224
 225 static void nct5104d_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 226 {
 227         int err;
 228         struct nct5104d_gpio_bank *bank =
 229                 container_of(chip, struct nct5104d_gpio_bank, chip);
 230         struct nct5104d_sio *sio = bank->data->sio;
 231         u8 data_out;
 232
 233         err = superio_enter(sio->addr);
 234         if (err)
 235                 return;
 236         superio_select(sio->addr, SIO_LD_GPIO);
 237
 238         data_out = superio_inb(sio->addr, gpio_data(bank->regbase));
 239         if (value)
 240                 data_out |= (1 << offset);
 241         else
 242                 data_out &= ~(1 << offset);
 243         superio_outb(sio->addr, gpio_data(bank->regbase), data_out);
 244
 245         superio_exit(sio->addr);
 246 }
 247
 248 /*
 249  * Platform device and driver.
 250  */
 251
 252 static int nct5104d_gpio_probe(struct platform_device *pdev)
 253 {
 254         int err;
 255         int i;
 256         struct nct5104d_sio *sio = pdev->dev.platform_data;
 257         struct nct5104d_gpio_data *data;
 258
 259         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
 260         if (!data)
 261                 return -ENOMEM;
 262
 263         switch (sio->type) {
 264         case nct5104d:
 265                 data->nr_bank = ARRAY_SIZE(nct5104d_gpio_bank);
 266                 data->bank = nct5104d_gpio_bank;
 267                 break;
 268         default:
 269                 return -ENODEV;
 270         }
 271         data->sio = sio;
 272
 273         platform_set_drvdata(pdev, data);
 274
 275         /* For each GPIO bank, register a GPIO chip. */
 276         for (i = 0; i < data->nr_bank; i++) {
 277                 struct nct5104d_gpio_bank *bank = &data->bank[i];
 278
 279 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,5,0)
 280                 bank->chip.dev = &pdev->dev;
 281 #else
 282                 bank->chip.parent = &pdev->dev;
 283 #endif
 284                 bank->data = data;
 285
 286                 err = gpiochip_add(&bank->chip);
 287                 if (err) {
 288                         dev_err(&pdev->dev,
 289                                 "Failed to register gpiochip %d: %d\n",
 290                                 i, err);
 291                         goto err_gpiochip;
 292                 }
 293         }
 294
 295         return 0;
 296
 297 err_gpiochip:
 298         for (i = i - 1; i >= 0; i--) {
 299                 struct nct5104d_gpio_bank *bank = &data->bank[i];
 300
 301 #if LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0)
 302                 int rm_err = gpiochip_remove(&bank->chip);
 303                 if (rm_err < 0)
 304                         dev_err(&pdev->dev,
 305                                 "Failed to remove gpiochip %d: %d\n",
 306                                 i, rm_err);
 307 #else /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */
 308                 gpiochip_remove (&bank->chip);
 309 #endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */
 310         }
 311
 312         return err;
 313 }
 314
 315 static int nct5104d_gpio_remove(struct platform_device *pdev)
 316 {
 317         int i;
 318         struct nct5104d_gpio_data *data = platform_get_drvdata(pdev);
 319
 320         for (i = 0; i < data->nr_bank; i++) {
 321                 struct nct5104d_gpio_bank *bank = &data->bank[i];
 322
 323 #if LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0)
 324                 int err = gpiochip_remove(&bank->chip);
 325                 if (err) {
 326                         dev_err(&pdev->dev,
 327                                 "Failed to remove GPIO gpiochip %d: %d\n",
 328                                 i, err);
 329                         return err;
 330                 }
 331 #else /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */
 332                 gpiochip_remove (&bank->chip);
 333 #endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3,18,0) */
 334         }
 335
 336         return 0;
 337 }
 338
 339 static int __init nct5104d_find(int addr, struct nct5104d_sio *sio)
 340 {
 341         int err;
 342         u16 devid;
 343         u8 gpio_cfg;
 344
 345         err = superio_enter(addr);
 346         if (err)
 347                 return err;
 348
 349         err = -ENODEV;
 350
 351         devid = superio_inw(addr, SIO_CHIPID);
 352         switch (devid) {
 353         case SIO_NCT5104D_ID:
 354         case SIO_PCENGINES_APU_NCT5104D_ID1:
 355         case SIO_PCENGINES_APU_NCT5104D_ID2:
 356                 sio->type = nct5104d;
 357                 /* enable GPIO0 and GPIO1 */
 358                 superio_select(addr, SIO_LD_GPIO);
 359                 gpio_cfg = superio_inb(addr, SIO_GPIO_ENABLE);
 360                 gpio_cfg |= 0x03;
 361                 superio_outb(addr, SIO_GPIO_ENABLE, gpio_cfg);
 362                 break;
 363         default:
 364                 pr_info(DRVNAME ": Unsupported device 0x%04x\n", devid);
 365                 goto err;
 366         }
 367         sio->addr = addr;
 368         err = 0;
 369
 370         pr_info(DRVNAME ": Found %s at %#x chip id 0x%04x\n",
 371                 nct5104d_names[sio->type],
 372                 (unsigned int) addr,
 373                 (int) superio_inw(addr, SIO_CHIPID));
 374
 375         superio_select(sio->addr, SIO_LD_GPIO_MODE);
 376         superio_outb(sio->addr, SIO_GPIO1_MODE, 0x0);
 377         superio_outb(sio->addr, SIO_GPIO2_MODE, 0x0);
 378
 379 err:
 380         superio_exit(addr);
 381         return err;
 382 }
 383
 384 static struct platform_device *nct5104d_gpio_pdev;
 385
 386 static int __init
 387 nct5104d_gpio_device_add(const struct nct5104d_sio *sio)
 388 {
 389         int err;
 390
 391         nct5104d_gpio_pdev = platform_device_alloc(DRVNAME, -1);
 392         if (!nct5104d_gpio_pdev)
 393                 pr_err(DRVNAME ": Error platform_device_alloc\n");
 394         if (!nct5104d_gpio_pdev)
 395                 return -ENOMEM;
 396
 397         err = platform_device_add_data(nct5104d_gpio_pdev,
 398                                        sio, sizeof(*sio));
 399         if (err) {
 400                 pr_err(DRVNAME "Platform data allocation failed\n");
 401                 goto err;
 402         }
 403
 404         err = platform_device_add(nct5104d_gpio_pdev);
 405         if (err) {
 406                 pr_err(DRVNAME "Device addition failed\n");
 407                 goto err;
 408         }
 409         pr_info(DRVNAME ": Device added\n");
 410         return 0;
 411
 412 err:
 413         platform_device_put(nct5104d_gpio_pdev);
 414
 415         return err;
 416 }
 417
 418 /*
 419  */
 420
 421 static struct platform_driver nct5104d_gpio_driver = {
 422         .driver = {
 423                 .owner  = THIS_MODULE,
 424                 .name   = DRVNAME,
 425         },
 426         .probe          = nct5104d_gpio_probe,
 427         .remove         = nct5104d_gpio_remove,
 428 };
 429
 430 static int __init nct5104d_gpio_init(void)
 431 {
 432         int err;
 433         struct nct5104d_sio sio;
 434         const char *board_vendor = dmi_get_system_info(DMI_BOARD_VENDOR);
 435         const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
 436
 437         /* Make sure we only run on PC Engine APU boards */
 438         if (!board_name || !board_vendor || strcasecmp(board_vendor, "PC Engines") || strncasecmp(board_name, "apu", 3)) {
 439                 return -ENODEV;
 440         }
 441
 442         if (nct5104d_find(0x2e, &sio) &&
 443             nct5104d_find(0x4e, &sio))
 444                 return -ENODEV;
 445
 446         err = platform_driver_register(&nct5104d_gpio_driver);
 447         if (!err) {
 448                 pr_info(DRVNAME ": platform_driver_register\n");
 449                 err = nct5104d_gpio_device_add(&sio);
 450                 if (err)
 451                         platform_driver_unregister(&nct5104d_gpio_driver);
 452         }
 453
 454         return err;
 455 }
 456 subsys_initcall(nct5104d_gpio_init);
 457
 458 static void __exit nct5104d_gpio_exit(void)
 459 {
 460         platform_device_unregister(nct5104d_gpio_pdev);
 461         platform_driver_unregister(&nct5104d_gpio_driver);
 462 }
 463 module_exit(nct5104d_gpio_exit);
 464
 465 MODULE_DESCRIPTION("GPIO driver for Super-I/O chips NCT5104D");
 466 MODULE_AUTHOR("Tasanakorn Phaipool <tasanakorn@gmail.com>");
 467 MODULE_LICENSE("GPL");