drivers/gpio/sch_gpio.c

   1 /*
   2  *  sch_gpio.c - GPIO interface for Intel Poulsbo SCH
   3  *
   4  *  Copyright (c) 2010 CompuLab Ltd
   5  *  Author: Denis Turischev <denis@compulab.co.il>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License 2 as published
   9  *  by the Free Software Foundation.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; see the file COPYING.  If not, write to
  18  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/io.h>
  25 #include <linux/errno.h>
  26 #include <linux/acpi.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/pci_ids.h>
  29
  30 #include <linux/gpio.h>
  31
  32 static DEFINE_SPINLOCK(gpio_lock);
  33
  34 #define CGEN    (0x00)
  35 #define CGIO    (0x04)
  36 #define CGLV    (0x08)
  37
  38 #define RGEN    (0x20)
  39 #define RGIO    (0x24)
  40 #define RGLV    (0x28)
  41
  42 static unsigned short gpio_ba;
  43
  44 static int sch_gpio_core_direction_in(struct gpio_chip *gc, unsigned  gpio_num)
  45 {
  46         u8 curr_dirs;
  47         unsigned short offset, bit;
  48
  49         spin_lock(&gpio_lock);
  50
  51         offset = CGIO + gpio_num / 8;
  52         bit = gpio_num % 8;
  53
  54         curr_dirs = inb(gpio_ba + offset);
  55
  56         if (!(curr_dirs & (1 << bit)))
  57                 outb(curr_dirs | (1 << bit), gpio_ba + offset);
  58
  59         spin_unlock(&gpio_lock);
  60         return 0;
  61 }
  62
  63 static int sch_gpio_core_get(struct gpio_chip *gc, unsigned gpio_num)
  64 {
  65         int res;
  66         unsigned short offset, bit;
  67
  68         offset = CGLV + gpio_num / 8;
  69         bit = gpio_num % 8;
  70
  71         res = !!(inb(gpio_ba + offset) & (1 << bit));
  72         return res;
  73 }
  74
  75 static void sch_gpio_core_set(struct gpio_chip *gc, unsigned gpio_num, int val)
  76 {
  77         u8 curr_vals;
  78         unsigned short offset, bit;
  79
  80         spin_lock(&gpio_lock);
  81
  82         offset = CGLV + gpio_num / 8;
  83         bit = gpio_num % 8;
  84
  85         curr_vals = inb(gpio_ba + offset);
  86
  87         if (val)
  88                 outb(curr_vals | (1 << bit), gpio_ba + offset);
  89         else
  90                 outb((curr_vals & ~(1 << bit)), gpio_ba + offset);
  91         spin_unlock(&gpio_lock);
  92 }
  93
  94 static int sch_gpio_core_direction_out(struct gpio_chip *gc,
  95                                         unsigned gpio_num, int val)
  96 {
  97         u8 curr_dirs;
  98         unsigned short offset, bit;
  99
 100         sch_gpio_core_set(gc, gpio_num, val);
 101
 102         spin_lock(&gpio_lock);
 103
 104         offset = CGIO + gpio_num / 8;
 105         bit = gpio_num % 8;
 106
 107         curr_dirs = inb(gpio_ba + offset);
 108         if (curr_dirs & (1 << bit))
 109                 outb(curr_dirs & ~(1 << bit), gpio_ba + offset);
 110
 111         spin_unlock(&gpio_lock);
 112         return 0;
 113 }
 114
 115 static struct gpio_chip sch_gpio_core = {
 116         .label                  = "sch_gpio_core",
 117         .owner                  = THIS_MODULE,
 118         .direction_input        = sch_gpio_core_direction_in,
 119         .get                    = sch_gpio_core_get,
 120         .direction_output       = sch_gpio_core_direction_out,
 121         .set                    = sch_gpio_core_set,
 122 };
 123
 124 static int sch_gpio_resume_direction_in(struct gpio_chip *gc,
 125                                         unsigned gpio_num)
 126 {
 127         u8 curr_dirs;
 128
 129         spin_lock(&gpio_lock);
 130
 131         curr_dirs = inb(gpio_ba + RGIO);
 132
 133         if (!(curr_dirs & (1 << gpio_num)))
 134                 outb(curr_dirs | (1 << gpio_num) , gpio_ba + RGIO);
 135
 136         spin_unlock(&gpio_lock);
 137         return 0;
 138 }
 139
 140 static int sch_gpio_resume_get(struct gpio_chip *gc, unsigned gpio_num)
 141 {
 142         return !!(inb(gpio_ba + RGLV) & (1 << gpio_num));
 143 }
 144
 145 static void sch_gpio_resume_set(struct gpio_chip *gc,
 146                                 unsigned gpio_num, int val)
 147 {
 148         u8 curr_vals;
 149
 150         spin_lock(&gpio_lock);
 151
 152         curr_vals = inb(gpio_ba + RGLV);
 153
 154         if (val)
 155                 outb(curr_vals | (1 << gpio_num), gpio_ba + RGLV);
 156         else
 157                 outb((curr_vals & ~(1 << gpio_num)), gpio_ba + RGLV);
 158
 159         spin_unlock(&gpio_lock);
 160 }
 161
 162 static int sch_gpio_resume_direction_out(struct gpio_chip *gc,
 163                                         unsigned gpio_num, int val)
 164 {
 165         u8 curr_dirs;
 166
 167         sch_gpio_resume_set(gc, gpio_num, val);
 168
 169         spin_lock(&gpio_lock);
 170
 171         curr_dirs = inb(gpio_ba + RGIO);
 172         if (curr_dirs & (1 << gpio_num))
 173                 outb(curr_dirs & ~(1 << gpio_num), gpio_ba + RGIO);
 174
 175         spin_unlock(&gpio_lock);
 176         return 0;
 177 }
 178
 179 static struct gpio_chip sch_gpio_resume = {
 180         .label                  = "sch_gpio_resume",
 181         .owner                  = THIS_MODULE,
 182         .direction_input        = sch_gpio_resume_direction_in,
 183         .get                    = sch_gpio_resume_get,
 184         .direction_output       = sch_gpio_resume_direction_out,
 185         .set                    = sch_gpio_resume_set,
 186 };
 187
 188 static int __devinit sch_gpio_probe(struct platform_device *pdev)
 189 {
 190         struct resource *res;
 191         int err, id;
 192
 193         id = pdev->id;
 194         if (!id)
 195                 return -ENODEV;
 196
 197         res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 198         if (!res)
 199                 return -EBUSY;
 200
 201         if (!request_region(res->start, resource_size(res), pdev->name))
 202                 return -EBUSY;
 203
 204         gpio_ba = res->start;
 205
 206         switch (id) {
 207                 case PCI_DEVICE_ID_INTEL_SCH_LPC:
 208                         sch_gpio_core.base = 0;
 209                         sch_gpio_core.ngpio = 10;
 210
 211                         sch_gpio_resume.base = 10;
 212                         sch_gpio_resume.ngpio = 4;
 213
 214                         /*
 215                          * GPIO[6:0] enabled by default
 216                          * GPIO7 is configured by the CMC as SLPIOVR
 217                          * Enable GPIO[9:8] core powered gpios explicitly
 218                          */
 219                         outb(0x3, gpio_ba + CGEN + 1);
 220                         /*
 221                          * SUS_GPIO[2:0] enabled by default
 222                          * Enable SUS_GPIO3 resume powered gpio explicitly
 223                          */
 224                         outb(0x8, gpio_ba + RGEN);
 225                         break;
 226
 227                 case PCI_DEVICE_ID_INTEL_ITC_LPC:
 228                         sch_gpio_core.base = 0;
 229                         sch_gpio_core.ngpio = 5;
 230
 231                         sch_gpio_resume.base = 5;
 232                         sch_gpio_resume.ngpio = 9;
 233                         break;
 234
 235                 default:
 236                         return -ENODEV;
 237         }
 238
 239         sch_gpio_core.dev = &pdev->dev;
 240         sch_gpio_resume.dev = &pdev->dev;
 241
 242         err = gpiochip_add(&sch_gpio_core);
 243         if (err < 0)
 244                 goto err_sch_gpio_core;
 245
 246         err = gpiochip_add(&sch_gpio_resume);
 247         if (err < 0)
 248                 goto err_sch_gpio_resume;
 249
 250         return 0;
 251
 252 err_sch_gpio_resume:
 253         err = gpiochip_remove(&sch_gpio_core);
 254         if (err)
 255                 dev_err(&pdev->dev, "%s failed, %d\n",
 256                                 "gpiochip_remove()", err);
 257
 258 err_sch_gpio_core:
 259         release_region(res->start, resource_size(res));
 260         gpio_ba = 0;
 261
 262         return err;
 263 }
 264
 265 static int __devexit sch_gpio_remove(struct platform_device *pdev)
 266 {
 267         struct resource *res;
 268         if (gpio_ba) {
 269                 int err;
 270
 271                 err  = gpiochip_remove(&sch_gpio_core);
 272                 if (err)
 273                         dev_err(&pdev->dev, "%s failed, %d\n",
 274                                 "gpiochip_remove()", err);
 275                 err = gpiochip_remove(&sch_gpio_resume);
 276                 if (err)
 277                         dev_err(&pdev->dev, "%s failed, %d\n",
 278                                 "gpiochip_remove()", err);
 279
 280                 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
 281
 282                 release_region(res->start, resource_size(res));
 283                 gpio_ba = 0;
 284
 285                 return err;
 286         }
 287
 288         return 0;
 289 }
 290
 291 static struct platform_driver sch_gpio_driver = {
 292         .driver = {
 293                 .name = "sch_gpio",
 294                 .owner = THIS_MODULE,
 295         },
 296         .probe          = sch_gpio_probe,
 297         .remove         = __devexit_p(sch_gpio_remove),
 298 };
 299
 300 static int __init sch_gpio_init(void)
 301 {
 302         return platform_driver_register(&sch_gpio_driver);
 303 }
 304
 305 static void __exit sch_gpio_exit(void)
 306 {
 307         platform_driver_unregister(&sch_gpio_driver);
 308 }
 309
 310 module_init(sch_gpio_init);
 311 module_exit(sch_gpio_exit);
 312
 313 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
 314 MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH");
 315 MODULE_LICENSE("GPL");
 316 MODULE_ALIAS("platform:sch_gpio");