drivers/gpio/gpio-sch311x.c

   1 /*
   2  * GPIO driver for the SMSC SCH311x Super-I/O chips
   3  *
   4  * Copyright (C) 2013 Bruno Randolf <br1@einfach.org>
   5  *
   6  * SuperIO functions and chip detection:
   7  * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/gpio.h>
  20 #include <linux/bitops.h>
  21 #include <linux/io.h>
  22
  23 #define DRV_NAME                        "gpio-sch311x"
  24
  25 #define SCH311X_GPIO_CONF_OUT           0x00
  26 #define SCH311X_GPIO_CONF_IN            0x01
  27 #define SCH311X_GPIO_CONF_INVERT        0x02
  28 #define SCH311X_GPIO_CONF_OPEN_DRAIN    0x80
  29
  30 #define SIO_CONFIG_KEY_ENTER            0x55
  31 #define SIO_CONFIG_KEY_EXIT             0xaa
  32
  33 #define GP1                             0x4b
  34
  35 static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };
  36
  37 static struct platform_device *sch311x_gpio_pdev;
  38
  39 struct sch311x_pdev_data {              /* platform device data */
  40         unsigned short runtime_reg;     /* runtime register base address */
  41 };
  42
  43 struct sch311x_gpio_block {             /* one GPIO block runtime data */
  44         struct gpio_chip chip;
  45         unsigned short data_reg;        /* from definition below */
  46         unsigned short *config_regs;    /* pointer to definition below */
  47         unsigned short runtime_reg;     /* runtime register */
  48         spinlock_t lock;                /* lock for this GPIO block */
  49 };
  50
  51 struct sch311x_gpio_priv {              /* driver private data */
  52         struct sch311x_gpio_block blocks[6];
  53 };
  54
  55 struct sch311x_gpio_block_def {         /* register address definitions */
  56         unsigned short data_reg;
  57         unsigned short config_regs[8];
  58         unsigned short base;
  59 };
  60
  61 /* Note: some GPIOs are not available, these are marked with 0x00 */
  62
  63 static struct sch311x_gpio_block_def sch311x_gpio_blocks[] = {
  64         {
  65                 .data_reg = 0x4b,       /* GP1 */
  66                 .config_regs = {0x23, 0x24, 0x25, 0x26, 0x27, 0x29, 0x2a, 0x2b},
  67                 .base = 10,
  68         },
  69         {
  70                 .data_reg = 0x4c,       /* GP2 */
  71                 .config_regs = {0x00, 0x2c, 0x2d, 0x00, 0x00, 0x00, 0x00, 0x32},
  72                 .base = 20,
  73         },
  74         {
  75                 .data_reg = 0x4d,       /* GP3 */
  76                 .config_regs = {0x33, 0x34, 0x35, 0x36, 0x37, 0x00, 0x39, 0x3a},
  77                 .base = 30,
  78         },
  79         {
  80                 .data_reg = 0x4e,       /* GP4 */
  81                 .config_regs = {0x3b, 0x00, 0x3d, 0x00, 0x6e, 0x6f, 0x72, 0x73},
  82                 .base = 40,
  83         },
  84         {
  85                 .data_reg = 0x4f,       /* GP5 */
  86                 .config_regs = {0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46},
  87                 .base = 50,
  88         },
  89         {
  90                 .data_reg = 0x50,       /* GP6 */
  91                 .config_regs = {0x47, 0x48, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59},
  92                 .base = 60,
  93         },
  94 };
  95
  96 /*
  97  *      Super-IO functions
  98  */
  99
 100 static inline int sch311x_sio_enter(int sio_config_port)
 101 {
 102         /* Don't step on other drivers' I/O space by accident. */
 103         if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
 104                 pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
 105                        sio_config_port);
 106                 return -EBUSY;
 107         }
 108
 109         outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
 110         return 0;
 111 }
 112
 113 static inline void sch311x_sio_exit(int sio_config_port)
 114 {
 115         outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
 116         release_region(sio_config_port, 2);
 117 }
 118
 119 static inline int sch311x_sio_inb(int sio_config_port, int reg)
 120 {
 121         outb(reg, sio_config_port);
 122         return inb(sio_config_port + 1);
 123 }
 124
 125 static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
 126 {
 127         outb(reg, sio_config_port);
 128         outb(val, sio_config_port + 1);
 129 }
 130
 131
 132 /*
 133  *      GPIO functions
 134  */
 135
 136 static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
 137 {
 138         struct sch311x_gpio_block *block = gpiochip_get_data(chip);
 139
 140         if (block->config_regs[offset] == 0) /* GPIO is not available */
 141                 return -ENODEV;
 142
 143         if (!request_region(block->runtime_reg + block->config_regs[offset],
 144                             1, DRV_NAME)) {
 145                 dev_err(chip->parent, "Failed to request region 0x%04x.\n",
 146                         block->runtime_reg + block->config_regs[offset]);
 147                 return -EBUSY;
 148         }
 149         return 0;
 150 }
 151
 152 static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
 153 {
 154         struct sch311x_gpio_block *block = gpiochip_get_data(chip);
 155
 156         if (block->config_regs[offset] == 0) /* GPIO is not available */
 157                 return;
 158
 159         release_region(block->runtime_reg + block->config_regs[offset], 1);
 160 }
 161
 162 static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
 163 {
 164         struct sch311x_gpio_block *block = gpiochip_get_data(chip);
 165         unsigned char data;
 166
 167         spin_lock(&block->lock);
 168         data = inb(block->runtime_reg + block->data_reg);
 169         spin_unlock(&block->lock);
 170
 171         return !!(data & BIT(offset));
 172 }
 173
 174 static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
 175                                unsigned offset, int value)
 176 {
 177         unsigned char data = inb(block->runtime_reg + block->data_reg);
 178         if (value)
 179                 data |= BIT(offset);
 180         else
 181                 data &= ~BIT(offset);
 182         outb(data, block->runtime_reg + block->data_reg);
 183 }
 184
 185 static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
 186                              int value)
 187 {
 188         struct sch311x_gpio_block *block = gpiochip_get_data(chip);
 189
 190         spin_lock(&block->lock);
 191          __sch311x_gpio_set(block, offset, value);
 192         spin_unlock(&block->lock);
 193 }
 194
 195 static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 196 {
 197         struct sch311x_gpio_block *block = gpiochip_get_data(chip);
 198
 199         spin_lock(&block->lock);
 200         outb(SCH311X_GPIO_CONF_IN, block->runtime_reg +
 201              block->config_regs[offset]);
 202         spin_unlock(&block->lock);
 203
 204         return 0;
 205 }
 206
 207 static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
 208                                       int value)
 209 {
 210         struct sch311x_gpio_block *block = gpiochip_get_data(chip);
 211
 212         spin_lock(&block->lock);
 213
 214         outb(SCH311X_GPIO_CONF_OUT, block->runtime_reg +
 215              block->config_regs[offset]);
 216
 217         __sch311x_gpio_set(block, offset, value);
 218
 219         spin_unlock(&block->lock);
 220         return 0;
 221 }
 222
 223 static int sch311x_gpio_probe(struct platform_device *pdev)
 224 {
 225         struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
 226         struct sch311x_gpio_priv *priv;
 227         struct sch311x_gpio_block *block;
 228         int err, i;
 229
 230         /* we can register all GPIO data registers at once */
 231         if (!request_region(pdata->runtime_reg + GP1, 6, DRV_NAME)) {
 232                 dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
 233                         pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
 234                 return -EBUSY;
 235         }
 236
 237         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 238         if (!priv)
 239                 return -ENOMEM;
 240
 241         platform_set_drvdata(pdev, priv);
 242
 243         for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
 244                 block = &priv->blocks[i];
 245
 246                 spin_lock_init(&block->lock);
 247
 248                 block->chip.label = DRV_NAME;
 249                 block->chip.owner = THIS_MODULE;
 250                 block->chip.request = sch311x_gpio_request;
 251                 block->chip.free = sch311x_gpio_free;
 252                 block->chip.direction_input = sch311x_gpio_direction_in;
 253                 block->chip.direction_output = sch311x_gpio_direction_out;
 254                 block->chip.get = sch311x_gpio_get;
 255                 block->chip.set = sch311x_gpio_set;
 256                 block->chip.ngpio = 8;
 257                 block->chip.parent = &pdev->dev;
 258                 block->chip.base = sch311x_gpio_blocks[i].base;
 259                 block->config_regs = sch311x_gpio_blocks[i].config_regs;
 260                 block->data_reg = sch311x_gpio_blocks[i].data_reg;
 261                 block->runtime_reg = pdata->runtime_reg;
 262
 263                 err = gpiochip_add_data(&block->chip, block);
 264                 if (err < 0) {
 265                         dev_err(&pdev->dev,
 266                                 "Could not register gpiochip, %d\n", err);
 267                         goto exit_err;
 268                 }
 269                 dev_info(&pdev->dev,
 270                          "SMSC SCH311x GPIO block %d registered.\n", i);
 271         }
 272
 273         return 0;
 274
 275 exit_err:
 276         release_region(pdata->runtime_reg + GP1, 6);
 277         /* release already registered chips */
 278         for (--i; i >= 0; i--)
 279                 gpiochip_remove(&priv->blocks[i].chip);
 280         return err;
 281 }
 282
 283 static int sch311x_gpio_remove(struct platform_device *pdev)
 284 {
 285         struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
 286         struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
 287         int i;
 288
 289         release_region(pdata->runtime_reg + GP1, 6);
 290
 291         for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
 292                 gpiochip_remove(&priv->blocks[i].chip);
 293                 dev_info(&pdev->dev,
 294                          "SMSC SCH311x GPIO block %d unregistered.\n", i);
 295         }
 296         return 0;
 297 }
 298
 299 static struct platform_driver sch311x_gpio_driver = {
 300         .driver.name    = DRV_NAME,
 301         .driver.owner   = THIS_MODULE,
 302         .probe          = sch311x_gpio_probe,
 303         .remove         = sch311x_gpio_remove,
 304 };
 305
 306
 307 /*
 308  *      Init & exit routines
 309  */
 310
 311 static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
 312 {
 313         int err = 0, reg;
 314         unsigned short base_addr;
 315         unsigned char dev_id;
 316
 317         err = sch311x_sio_enter(sio_config_port);
 318         if (err)
 319                 return err;
 320
 321         /* Check device ID. */
 322         reg = sch311x_sio_inb(sio_config_port, 0x20);
 323         switch (reg) {
 324         case 0x7c: /* SCH3112 */
 325                 dev_id = 2;
 326                 break;
 327         case 0x7d: /* SCH3114 */
 328                 dev_id = 4;
 329                 break;
 330         case 0x7f: /* SCH3116 */
 331                 dev_id = 6;
 332                 break;
 333         default:
 334                 err = -ENODEV;
 335                 goto exit;
 336         }
 337
 338         /* Select logical device A (runtime registers) */
 339         sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
 340
 341         /* Check if Logical Device Register is currently active */
 342         if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
 343                 pr_info("Seems that LDN 0x0a is not active...\n");
 344
 345         /* Get the base address of the runtime registers */
 346         base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
 347                            sch311x_sio_inb(sio_config_port, 0x61);
 348         if (!base_addr) {
 349                 pr_err("Base address not set\n");
 350                 err = -ENODEV;
 351                 goto exit;
 352         }
 353         *addr = base_addr;
 354
 355         pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
 356
 357 exit:
 358         sch311x_sio_exit(sio_config_port);
 359         return err;
 360 }
 361
 362 static int __init sch311x_gpio_pdev_add(const unsigned short addr)
 363 {
 364         struct sch311x_pdev_data pdata;
 365         int err;
 366
 367         pdata.runtime_reg = addr;
 368
 369         sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
 370         if (!sch311x_gpio_pdev)
 371                 return -ENOMEM;
 372
 373         err = platform_device_add_data(sch311x_gpio_pdev,
 374                                        &pdata, sizeof(pdata));
 375         if (err) {
 376                 pr_err(DRV_NAME "Platform data allocation failed\n");
 377                 goto err;
 378         }
 379
 380         err = platform_device_add(sch311x_gpio_pdev);
 381         if (err) {
 382                 pr_err(DRV_NAME "Device addition failed\n");
 383                 goto err;
 384         }
 385         return 0;
 386
 387 err:
 388         platform_device_put(sch311x_gpio_pdev);
 389         return err;
 390 }
 391
 392 static int __init sch311x_gpio_init(void)
 393 {
 394         int err, i;
 395         unsigned short addr = 0;
 396
 397         for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
 398                 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
 399                         break;
 400
 401         if (!addr)
 402                 return -ENODEV;
 403
 404         err = platform_driver_register(&sch311x_gpio_driver);
 405         if (err)
 406                 return err;
 407
 408         err = sch311x_gpio_pdev_add(addr);
 409         if (err)
 410                 goto unreg_platform_driver;
 411
 412         return 0;
 413
 414 unreg_platform_driver:
 415         platform_driver_unregister(&sch311x_gpio_driver);
 416         return err;
 417 }
 418
 419 static void __exit sch311x_gpio_exit(void)
 420 {
 421         platform_device_unregister(sch311x_gpio_pdev);
 422         platform_driver_unregister(&sch311x_gpio_driver);
 423 }
 424
 425 module_init(sch311x_gpio_init);
 426 module_exit(sch311x_gpio_exit);
 427
 428 MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
 429 MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
 430 MODULE_LICENSE("GPL");
 431 MODULE_ALIAS("platform:gpio-sch311x");