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