target/linux/s3c24xx/files-2.6.30/drivers/mfd/glamo/glamo-gpio.c

   1 /* Smedia Glamo 336x/337x gpio driver
   2  *
   3  * (C) 2009 Lars-Peter Clausen
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation; either version 2 of
   8  * the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  18  * MA 02111-1307 USA
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/io.h>
  26 #include <linux/platform_device.h>
  27
  28 #include <linux/gpio.h>
  29 #include <linux/mfd/glamo.h>
  30
  31 #include "glamo-core.h"
  32 #include "glamo-regs.h"
  33
  34 #define GLAMO_NR_GPIO 21
  35 #define GLAMO_NR_GPIO_REGS DIV_ROUND_UP(GLAMO_NR_GPIO, 4)
  36
  37 #define GLAMO_REG_GPIO(x) (((x) * 2) + GLAMO_REG_GPIO_GEN1)
  38
  39 struct glamo_gpio {
  40         struct glamo_core *glamo;
  41         struct gpio_chip chip;
  42         uint16_t saved_regs[GLAMO_NR_GPIO_REGS];
  43 };
  44
  45 #define REG_OF_GPIO(gpio)   (GLAMO_REG_GPIO(gpio >> 2))
  46 #define NUM_OF_GPIO(gpio)       (gpio & 0x3)
  47 #define DIRECTION_BIT(gpio)     (1 << (NUM_OF_GPIO(gpio) + 0))
  48 #define OUTPUT_BIT(gpio)        (1 << (NUM_OF_GPIO(gpio) + 4))
  49 #define INPUT_BIT(gpio)         (1 << (NUM_OF_GPIO(gpio) + 8))
  50 #define FUNC_BIT(gpio)          (1 << (NUM_OF_GPIO(gpio) + 12))
  51
  52
  53 static inline struct glamo_core *chip_to_glamo(struct gpio_chip *chip)
  54 {
  55         return container_of(chip, struct glamo_gpio, chip)->glamo;
  56 }
  57
  58 static void glamo_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  59 {
  60         struct glamo_core *glamo = chip_to_glamo(chip);
  61         unsigned int reg = REG_OF_GPIO(offset);
  62         u_int16_t tmp;
  63
  64         spin_lock(&glamo->lock);
  65         tmp = readw(glamo->base + reg);
  66         if (value)
  67                 tmp |= OUTPUT_BIT(offset);
  68         else
  69                 tmp &= ~OUTPUT_BIT(offset);
  70         writew(tmp, glamo->base + reg);
  71         spin_unlock(&glamo->lock);
  72 }
  73
  74 static int glamo_gpio_get(struct gpio_chip *chip, unsigned offset)
  75 {
  76         struct glamo_core *glamo = chip_to_glamo(chip);
  77         return readw(glamo->base + REG_OF_GPIO(offset)) & INPUT_BIT(offset) ? 1 : 0;
  78 }
  79
  80 static int glamo_gpio_request(struct gpio_chip *chip, unsigned offset)
  81 {
  82         struct glamo_core *glamo = chip_to_glamo(chip);
  83         unsigned int reg = REG_OF_GPIO(offset);
  84         u_int16_t tmp;
  85
  86         spin_lock(&glamo->lock);
  87         tmp = readw(glamo->base + reg);
  88         if ((tmp & FUNC_BIT(offset)) == 0) {
  89                 tmp |= FUNC_BIT(offset);
  90                 writew(tmp, glamo->base + reg);
  91         }
  92         spin_unlock(&glamo->lock);
  93
  94         return 0;
  95 }
  96
  97 static void glamo_gpio_free(struct gpio_chip *chip, unsigned offset)
  98 {
  99         struct glamo_core *glamo = chip_to_glamo(chip);
 100         unsigned int reg = REG_OF_GPIO(offset);
 101         u_int16_t tmp;
 102
 103         spin_lock(&glamo->lock);
 104         tmp = readw(glamo->base + reg);
 105         if ((tmp & FUNC_BIT(offset)) == 1) {
 106                 tmp &= ~FUNC_BIT(offset);
 107                 writew(tmp, glamo->base + reg);
 108         }
 109         spin_unlock(&glamo->lock);
 110 }
 111
 112 static int glamo_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 113                                                 int value)
 114 {
 115         struct glamo_core *glamo = chip_to_glamo(chip);
 116         unsigned int reg = REG_OF_GPIO(offset);
 117         u_int16_t tmp;
 118
 119         spin_lock(&glamo->lock);
 120         tmp = readw(glamo->base + reg);
 121     tmp &= ~DIRECTION_BIT(offset);
 122
 123         if (value)
 124                 tmp |= OUTPUT_BIT(offset);
 125         else
 126                 tmp &= ~OUTPUT_BIT(offset);
 127
 128         writew(tmp, glamo->base + reg);
 129         spin_unlock(&glamo->lock);
 130
 131         return 0;
 132 }
 133
 134 static int glamo_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 135 {
 136         struct glamo_core *glamo = chip_to_glamo(chip);
 137         unsigned int reg = REG_OF_GPIO(offset);
 138         u_int16_t tmp;
 139
 140         spin_lock(&glamo->lock);
 141         tmp = readw(glamo->base + reg);
 142         if ((tmp & DIRECTION_BIT(offset)) == 0) {
 143                 tmp |= DIRECTION_BIT(offset);
 144                 writew(tmp, glamo->base + reg);
 145         }
 146         spin_unlock(&glamo->lock);
 147
 148         return 0;
 149 }
 150
 151 static const struct __devinit gpio_chip glamo_gpio_chip = {
 152         .label                          = "glamo",
 153         .request                        = glamo_gpio_request,
 154         .free                           = glamo_gpio_free,
 155         .direction_input        = glamo_gpio_direction_input,
 156         .get                            = glamo_gpio_get,
 157         .direction_output       = glamo_gpio_direction_output,
 158         .set                            = glamo_gpio_set,
 159         .base                           = -1,
 160         .ngpio                          = GLAMO_NR_GPIO,
 161         .can_sleep                      = 0,
 162         .owner             = THIS_MODULE,
 163 };
 164
 165 static int __devinit glamo_gpio_probe(struct platform_device *pdev)
 166 {
 167         struct glamo_platform_data *pdata = pdev->dev.parent->platform_data;
 168         struct glamo_gpio *glamo_gpio;
 169         int ret;
 170
 171         glamo_gpio = kzalloc(sizeof(struct glamo_gpio), GFP_KERNEL);
 172         if (!glamo_gpio)
 173                 return -ENOMEM;
 174
 175         glamo_gpio->glamo = dev_get_drvdata(pdev->dev.parent);
 176         glamo_gpio->chip = glamo_gpio_chip;
 177         glamo_gpio->chip.dev = &pdev->dev;
 178         if (pdata)
 179                 glamo_gpio->chip.base = pdata->gpio_base;
 180
 181         ret = gpiochip_add(&glamo_gpio->chip);
 182
 183         if (ret) {
 184                 dev_err(&pdev->dev, "Could not register gpio chip: %d\n", ret);
 185                 goto err;
 186         }
 187
 188         platform_set_drvdata(pdev, glamo_gpio);
 189         return 0;
 190 err:
 191         kfree(glamo_gpio);
 192         return ret;
 193 }
 194
 195 static int __devexit glamo_gpio_remove(struct platform_device *pdev)
 196 {
 197         struct glamo_gpio *glamo_gpio = platform_get_drvdata(pdev);
 198         int ret;
 199
 200         ret = gpiochip_remove(&glamo_gpio->chip);
 201         if (!ret)
 202                 goto done;
 203
 204         platform_set_drvdata(pdev, NULL);
 205         kfree(glamo_gpio);
 206
 207 done:
 208         return ret;
 209 }
 210
 211 #ifdef CONFIG_PM
 212
 213 static int glamo_gpio_suspend(struct device *dev)
 214 {
 215         struct glamo_gpio *glamo_gpio = dev_get_drvdata(dev);
 216         struct glamo_core *glamo = glamo_gpio->glamo;
 217         uint16_t *saved_regs = glamo_gpio->saved_regs;
 218         int i;
 219
 220         spin_lock(&glamo->lock);
 221         for (i = 0; i < GLAMO_NR_GPIO / 4; ++i)
 222                 saved_regs[i] = readw(glamo->base + GLAMO_REG_GPIO(i));
 223         spin_unlock(&glamo->lock);
 224
 225         return 0;
 226 }
 227
 228 static int glamo_gpio_resume(struct device *dev)
 229 {
 230         struct glamo_gpio *glamo_gpio = dev_get_drvdata(dev);
 231         struct glamo_core *glamo = glamo_gpio->glamo;
 232         uint16_t *saved_regs = glamo_gpio->saved_regs;
 233         int i;
 234
 235         spin_lock(&glamo->lock);
 236         for (i = 0; i < GLAMO_NR_GPIO_REGS; ++i)
 237                 writew(saved_regs[i], glamo->base + GLAMO_REG_GPIO(i));
 238         spin_unlock(&glamo->lock);
 239         return 0;
 240 }
 241
 242 static const struct dev_pm_ops glamo_pm_ops = {
 243         .suspend = glamo_gpio_suspend,
 244         .resume  = glamo_gpio_resume,
 245         .freeze  = glamo_gpio_suspend,
 246         .thaw    = glamo_gpio_resume,
 247 };
 248
 249 #define GLAMO_GPIO_PM_OPS (&glamo_pm_ops)
 250
 251 #else
 252 #define GLAMO_GPIO_OPS NULL
 253 #endif
 254
 255 static struct platform_driver glamo_gpio_driver = {
 256         .driver = {
 257                 .name  = "glamo-gpio",
 258                 .owner = THIS_MODULE,
 259                 .pm    = GLAMO_GPIO_PM_OPS,
 260         },
 261         .probe = glamo_gpio_probe,
 262         .remove = __devexit_p(glamo_gpio_remove),
 263 };
 264
 265 static int __devinit glamo_gpio_init(void)
 266 {
 267         return platform_driver_register(&glamo_gpio_driver);
 268 }
 269
 270 static void __exit glamo_gpio_exit(void)
 271 {
 272         platform_driver_unregister(&glamo_gpio_driver);
 273 }
 274
 275 module_init(glamo_gpio_init);
 276 module_exit(glamo_gpio_exit);
 277
 278 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 279 MODULE_DESCRIPTION("GPIO interface for the Glamo multimedia device");
 280 MODULE_LICENSE("GPL");
 281 MODULE_ALIAS("platform:glamo-gpio");