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 static inline struct sch311x_gpio_block *
  97 to_sch311x_gpio_block(struct gpio_chip *chip)
  98 {
  99         return container_of(chip, struct sch311x_gpio_block, chip);
 100 }
 101
 102
 103 /*
 104  *      Super-IO functions
 105  */
 106
 107 static inline int sch311x_sio_enter(int sio_config_port)
 108 {
 109         /* Don't step on other drivers' I/O space by accident. */
 110         if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
 111                 pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
 112                        sio_config_port);
 113                 return -EBUSY;
 114         }
 115
 116         outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
 117         return 0;
 118 }
 119
 120 static inline void sch311x_sio_exit(int sio_config_port)
 121 {
 122         outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
 123         release_region(sio_config_port, 2);
 124 }
 125
 126 static inline int sch311x_sio_inb(int sio_config_port, int reg)
 127 {
 128         outb(reg, sio_config_port);
 129         return inb(sio_config_port + 1);
 130 }
 131
 132 static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
 133 {
 134         outb(reg, sio_config_port);
 135         outb(val, sio_config_port + 1);
 136 }
 137
 138
 139 /*
 140  *      GPIO functions
 141  */
 142
 143 static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
 144 {
 145         struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
 146
 147         if (block->config_regs[offset] == 0) /* GPIO is not available */
 148                 return -ENODEV;
 149
 150         if (!request_region(block->runtime_reg + block->config_regs[offset],
 151                             1, DRV_NAME)) {
 152                 dev_err(chip->dev, "Failed to request region 0x%04x.\n",
 153                         block->runtime_reg + block->config_regs[offset]);
 154                 return -EBUSY;
 155         }
 156         return 0;
 157 }
 158
 159 static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
 160 {
 161         struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
 162
 163         if (block->config_regs[offset] == 0) /* GPIO is not available */
 164                 return;
 165
 166         release_region(block->runtime_reg + block->config_regs[offset], 1);
 167 }
 168
 169 static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
 170 {
 171         struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
 172         unsigned char data;
 173
 174         spin_lock(&block->lock);
 175         data = inb(block->runtime_reg + block->data_reg);
 176         spin_unlock(&block->lock);
 177
 178         return !!(data & BIT(offset));
 179 }
 180
 181 static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
 182                                unsigned offset, int value)
 183 {
 184         unsigned char data = inb(block->runtime_reg + block->data_reg);
 185         if (value)
 186                 data |= BIT(offset);
 187         else
 188                 data &= ~BIT(offset);
 189         outb(data, block->runtime_reg + block->data_reg);
 190 }
 191
 192 static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
 193                              int value)
 194 {
 195         struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
 196
 197         spin_lock(&block->lock);
 198          __sch311x_gpio_set(block, offset, value);
 199         spin_unlock(&block->lock);
 200 }
 201
 202 static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 203 {
 204         struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
 205
 206         spin_lock(&block->lock);
 207         outb(SCH311X_GPIO_CONF_IN, block->runtime_reg +
 208              block->config_regs[offset]);
 209         spin_unlock(&block->lock);
 210
 211         return 0;
 212 }
 213
 214 static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
 215                                       int value)
 216 {
 217         struct sch311x_gpio_block *block = to_sch311x_gpio_block(chip);
 218
 219         spin_lock(&block->lock);
 220
 221         outb(SCH311X_GPIO_CONF_OUT, block->runtime_reg +
 222              block->config_regs[offset]);
 223
 224         __sch311x_gpio_set(block, offset, value);
 225
 226         spin_unlock(&block->lock);
 227         return 0;
 228 }
 229
 230 static int sch311x_gpio_probe(struct platform_device *pdev)
 231 {
 232         struct sch311x_pdev_data *pdata = pdev->dev.platform_data;
 233         struct sch311x_gpio_priv *priv;
 234         struct sch311x_gpio_block *block;
 235         int err, i;
 236
 237         /* we can register all GPIO data registers at once */
 238         if (!request_region(pdata->runtime_reg + GP1, 6, DRV_NAME)) {
 239                 dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
 240                         pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
 241                 return -EBUSY;
 242         }
 243
 244         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 245         if (!priv)
 246                 return -ENOMEM;
 247
 248         platform_set_drvdata(pdev, priv);
 249
 250         for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
 251                 block = &priv->blocks[i];
 252
 253                 spin_lock_init(&block->lock);
 254
 255                 block->chip.label = DRV_NAME;
 256                 block->chip.owner = THIS_MODULE;
 257                 block->chip.request = sch311x_gpio_request;
 258                 block->chip.free = sch311x_gpio_free;
 259                 block->chip.direction_input = sch311x_gpio_direction_in;
 260                 block->chip.direction_output = sch311x_gpio_direction_out;
 261                 block->chip.get = sch311x_gpio_get;
 262                 block->chip.set = sch311x_gpio_set;
 263                 block->chip.ngpio = 8;
 264                 block->chip.dev = &pdev->dev;
 265                 block->chip.base = sch311x_gpio_blocks[i].base;
 266                 block->config_regs = sch311x_gpio_blocks[i].config_regs;
 267                 block->data_reg = sch311x_gpio_blocks[i].data_reg;
 268                 block->runtime_reg = pdata->runtime_reg;
 269
 270                 err = gpiochip_add(&block->chip);
 271                 if (err < 0) {
 272                         dev_err(&pdev->dev,
 273                                 "Could not register gpiochip, %d\n", err);
 274                         goto exit_err;
 275                 }
 276                 dev_info(&pdev->dev,
 277                          "SMSC SCH311x GPIO block %d registered.\n", i);
 278         }
 279
 280         return 0;
 281
 282 exit_err:
 283         release_region(pdata->runtime_reg + GP1, 6);
 284         /* release already registered chips */
 285         for (--i; i >= 0; i--)
 286                 gpiochip_remove(&priv->blocks[i].chip);
 287         return err;
 288 }
 289
 290 static int sch311x_gpio_remove(struct platform_device *pdev)
 291 {
 292         struct sch311x_pdev_data *pdata = pdev->dev.platform_data;
 293         struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
 294         int err, i;
 295
 296         release_region(pdata->runtime_reg + GP1, 6);
 297
 298         for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
 299                 err = gpiochip_remove(&priv->blocks[i].chip);
 300                 if (err)
 301                         return err;
 302                 dev_info(&pdev->dev,
 303                          "SMSC SCH311x GPIO block %d unregistered.\n", i);
 304         }
 305         return 0;
 306 }
 307
 308 static struct platform_driver sch311x_gpio_driver = {
 309         .driver.name    = DRV_NAME,
 310         .driver.owner   = THIS_MODULE,
 311         .probe          = sch311x_gpio_probe,
 312         .remove         = sch311x_gpio_remove,
 313 };
 314
 315
 316 /*
 317  *      Init & exit routines
 318  */
 319
 320 static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
 321 {
 322         int err = 0, reg;
 323         unsigned short base_addr;
 324         unsigned char dev_id;
 325
 326         err = sch311x_sio_enter(sio_config_port);
 327         if (err)
 328                 return err;
 329
 330         /* Check device ID. We currently know about:
 331          * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */
 332         reg = sch311x_sio_inb(sio_config_port, 0x20);
 333         if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
 334                 err = -ENODEV;
 335                 goto exit;
 336         }
 337         dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6;
 338
 339         /* Select logical device A (runtime registers) */
 340         sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
 341
 342         /* Check if Logical Device Register is currently active */
 343         if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
 344                 pr_info("Seems that LDN 0x0a is not active...\n");
 345
 346         /* Get the base address of the runtime registers */
 347         base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
 348                            sch311x_sio_inb(sio_config_port, 0x61);
 349         if (!base_addr) {
 350                 pr_err("Base address not set\n");
 351                 err = -ENODEV;
 352                 goto exit;
 353         }
 354         *addr = base_addr;
 355
 356         pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
 357
 358 exit:
 359         sch311x_sio_exit(sio_config_port);
 360         return err;
 361 }
 362
 363 static int __init sch311x_gpio_pdev_add(const unsigned short addr)
 364 {
 365         struct sch311x_pdev_data pdata;
 366         int err;
 367
 368         pdata.runtime_reg = addr;
 369
 370         sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
 371         if (!sch311x_gpio_pdev)
 372                 return -ENOMEM;
 373
 374         err = platform_device_add_data(sch311x_gpio_pdev,
 375                                        &pdata, sizeof(pdata));
 376         if (err) {
 377                 pr_err(DRV_NAME "Platform data allocation failed\n");
 378                 goto err;
 379         }
 380
 381         err = platform_device_add(sch311x_gpio_pdev);
 382         if (err) {
 383                 pr_err(DRV_NAME "Device addition failed\n");
 384                 goto err;
 385         }
 386         return 0;
 387
 388 err:
 389         platform_device_put(sch311x_gpio_pdev);
 390         return err;
 391 }
 392
 393 static int __init sch311x_gpio_init(void)
 394 {
 395         int err, i;
 396         unsigned short addr = 0;
 397
 398         for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
 399                 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
 400                         break;
 401
 402         if (!addr)
 403                 return -ENODEV;
 404
 405         err = platform_driver_register(&sch311x_gpio_driver);
 406         if (err)
 407                 return err;
 408
 409         err = sch311x_gpio_pdev_add(addr);
 410         if (err)
 411                 goto unreg_platform_driver;
 412
 413         return 0;
 414
 415 unreg_platform_driver:
 416         platform_driver_unregister(&sch311x_gpio_driver);
 417         return err;
 418 }
 419
 420 static void __exit sch311x_gpio_exit(void)
 421 {
 422         platform_device_unregister(sch311x_gpio_pdev);
 423         platform_driver_unregister(&sch311x_gpio_driver);
 424 }
 425
 426 module_init(sch311x_gpio_init);
 427 module_exit(sch311x_gpio_exit);
 428
 429 MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
 430 MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
 431 MODULE_LICENSE("GPL");
 432 MODULE_ALIAS("platform:gpio-sch311x");