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                 bank->chip.parent = &pdev->dev;
 280                 bank->data = data;
 281
 282                 err = gpiochip_add(&bank->chip);
 283                 if (err) {
 284                         dev_err(&pdev->dev,
 285                                 "Failed to register gpiochip %d: %d\n",
 286                                 i, err);
 287                         goto err_gpiochip;
 288                 }
 289         }
 290
 291         return 0;
 292
 293 err_gpiochip:
 294         for (i = i - 1; i >= 0; i--) {
 295                 struct nct5104d_gpio_bank *bank = &data->bank[i];
 296
 297                 gpiochip_remove (&bank->chip);
 298         }
 299
 300         return err;
 301 }
 302
 303 static int nct5104d_gpio_remove(struct platform_device *pdev)
 304 {
 305         int i;
 306         struct nct5104d_gpio_data *data = platform_get_drvdata(pdev);
 307
 308         for (i = 0; i < data->nr_bank; i++) {
 309                 struct nct5104d_gpio_bank *bank = &data->bank[i];
 310
 311                 gpiochip_remove (&bank->chip);
 312         }
 313
 314         return 0;
 315 }
 316
 317 static int __init nct5104d_find(int addr, struct nct5104d_sio *sio)
 318 {
 319         int err;
 320         u16 devid;
 321         u8 gpio_cfg;
 322
 323         err = superio_enter(addr);
 324         if (err)
 325                 return err;
 326
 327         err = -ENODEV;
 328
 329         devid = superio_inw(addr, SIO_CHIPID);
 330         switch (devid) {
 331         case SIO_NCT5104D_ID:
 332         case SIO_PCENGINES_APU_NCT5104D_ID1:
 333         case SIO_PCENGINES_APU_NCT5104D_ID2:
 334                 sio->type = nct5104d;
 335                 /* enable GPIO0 and GPIO1 */
 336                 superio_select(addr, SIO_LD_GPIO);
 337                 gpio_cfg = superio_inb(addr, SIO_GPIO_ENABLE);
 338                 gpio_cfg |= 0x03;
 339                 superio_outb(addr, SIO_GPIO_ENABLE, gpio_cfg);
 340                 break;
 341         default:
 342                 pr_info(DRVNAME ": Unsupported device 0x%04x\n", devid);
 343                 goto err;
 344         }
 345         sio->addr = addr;
 346         err = 0;
 347
 348         pr_info(DRVNAME ": Found %s at %#x chip id 0x%04x\n",
 349                 nct5104d_names[sio->type],
 350                 (unsigned int) addr,
 351                 (int) superio_inw(addr, SIO_CHIPID));
 352
 353         superio_select(sio->addr, SIO_LD_GPIO_MODE);
 354         superio_outb(sio->addr, SIO_GPIO1_MODE, 0x0);
 355         superio_outb(sio->addr, SIO_GPIO2_MODE, 0x0);
 356
 357 err:
 358         superio_exit(addr);
 359         return err;
 360 }
 361
 362 static struct platform_device *nct5104d_gpio_pdev;
 363
 364 static int __init
 365 nct5104d_gpio_device_add(const struct nct5104d_sio *sio)
 366 {
 367         int err;
 368
 369         nct5104d_gpio_pdev = platform_device_alloc(DRVNAME, -1);
 370         if (!nct5104d_gpio_pdev)
 371                 pr_err(DRVNAME ": Error platform_device_alloc\n");
 372         if (!nct5104d_gpio_pdev)
 373                 return -ENOMEM;
 374
 375         err = platform_device_add_data(nct5104d_gpio_pdev,
 376                                        sio, sizeof(*sio));
 377         if (err) {
 378                 pr_err(DRVNAME "Platform data allocation failed\n");
 379                 goto err;
 380         }
 381
 382         err = platform_device_add(nct5104d_gpio_pdev);
 383         if (err) {
 384                 pr_err(DRVNAME "Device addition failed\n");
 385                 goto err;
 386         }
 387         pr_info(DRVNAME ": Device added\n");
 388         return 0;
 389
 390 err:
 391         platform_device_put(nct5104d_gpio_pdev);
 392
 393         return err;
 394 }
 395
 396 /*
 397  */
 398
 399 static struct platform_driver nct5104d_gpio_driver = {
 400         .driver = {
 401                 .owner  = THIS_MODULE,
 402                 .name   = DRVNAME,
 403         },
 404         .probe          = nct5104d_gpio_probe,
 405         .remove         = nct5104d_gpio_remove,
 406 };
 407
 408 static int __init nct5104d_gpio_init(void)
 409 {
 410         int err;
 411         struct nct5104d_sio sio;
 412         const char *board_vendor = dmi_get_system_info(DMI_BOARD_VENDOR);
 413         const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
 414
 415         if (nct5104d_find(0x2e, &sio) &&
 416             nct5104d_find(0x4e, &sio))
 417                 return -ENODEV;
 418
 419         err = platform_driver_register(&nct5104d_gpio_driver);
 420         if (!err) {
 421                 pr_info(DRVNAME ": platform_driver_register\n");
 422                 err = nct5104d_gpio_device_add(&sio);
 423                 if (err)
 424                         platform_driver_unregister(&nct5104d_gpio_driver);
 425         }
 426
 427         return err;
 428 }
 429 subsys_initcall(nct5104d_gpio_init);
 430
 431 static void __exit nct5104d_gpio_exit(void)
 432 {
 433         platform_device_unregister(nct5104d_gpio_pdev);
 434         platform_driver_unregister(&nct5104d_gpio_driver);
 435 }
 436 module_exit(nct5104d_gpio_exit);
 437
 438 MODULE_DESCRIPTION("GPIO driver for Super-I/O chips NCT5104D");
 439 MODULE_AUTHOR("Tasanakorn Phaipool <tasanakorn@gmail.com>");
 440 MODULE_LICENSE("GPL");