drivers/gpio/pch_gpio.c

   1 /*
   2  * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
  16  */
  17 #include <linux/kernel.h>
  18 #include <linux/pci.h>
  19 #include <linux/gpio.h>
  20
  21 #define PCH_GPIO_ALL_PINS       0xfff /* Mask for GPIO pins 0 to 11 */
  22 #define GPIO_NUM_PINS   12      /* Specifies number of GPIO PINS GPIO0-GPIO11 */
  23
  24 struct pch_regs {
  25         u32     ien;
  26         u32     istatus;
  27         u32     idisp;
  28         u32     iclr;
  29         u32     imask;
  30         u32     imaskclr;
  31         u32     po;
  32         u32     pi;
  33         u32     pm;
  34         u32     im0;
  35         u32     im1;
  36         u32     reserved[4];
  37         u32     reset;
  38 };
  39
  40 /**
  41  * struct pch_gpio_reg_data - The register store data.
  42  * @po_reg:     To store contents of PO register.
  43  * @pm_reg:     To store contents of PM register.
  44  */
  45 struct pch_gpio_reg_data {
  46         u32 po_reg;
  47         u32 pm_reg;
  48 };
  49
  50 /**
  51  * struct pch_gpio - GPIO private data structure.
  52  * @base:                       PCI base address of Memory mapped I/O register.
  53  * @reg:                        Memory mapped PCH GPIO register list.
  54  * @dev:                        Pointer to device structure.
  55  * @gpio:                       Data for GPIO infrastructure.
  56  * @pch_gpio_reg:               Memory mapped Register data is saved here
  57  *                              when suspend.
  58  */
  59 struct pch_gpio {
  60         void __iomem *base;
  61         struct pch_regs __iomem *reg;
  62         struct device *dev;
  63         struct gpio_chip gpio;
  64         struct pch_gpio_reg_data pch_gpio_reg;
  65         struct mutex lock;
  66 };
  67
  68 static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
  69 {
  70         u32 reg_val;
  71         struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
  72
  73         mutex_lock(&chip->lock);
  74         reg_val = ioread32(&chip->reg->po);
  75         if (val)
  76                 reg_val |= (1 << nr);
  77         else
  78                 reg_val &= ~(1 << nr);
  79
  80         iowrite32(reg_val, &chip->reg->po);
  81         mutex_unlock(&chip->lock);
  82 }
  83
  84 static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
  85 {
  86         struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
  87
  88         return ioread32(&chip->reg->pi) & (1 << nr);
  89 }
  90
  91 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
  92                                      int val)
  93 {
  94         struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
  95         u32 pm;
  96         u32 reg_val;
  97
  98         mutex_lock(&chip->lock);
  99         pm = ioread32(&chip->reg->pm) & PCH_GPIO_ALL_PINS;
 100         pm |= (1 << nr);
 101         iowrite32(pm, &chip->reg->pm);
 102
 103         reg_val = ioread32(&chip->reg->po);
 104         if (val)
 105                 reg_val |= (1 << nr);
 106         else
 107                 reg_val &= ~(1 << nr);
 108
 109         mutex_unlock(&chip->lock);
 110
 111         return 0;
 112 }
 113
 114 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
 115 {
 116         struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
 117         u32 pm;
 118
 119         mutex_lock(&chip->lock);
 120         pm = ioread32(&chip->reg->pm) & PCH_GPIO_ALL_PINS; /*bits 0-11*/
 121         pm &= ~(1 << nr);
 122         iowrite32(pm, &chip->reg->pm);
 123         mutex_unlock(&chip->lock);
 124
 125         return 0;
 126 }
 127
 128 /*
 129  * Save register configuration and disable interrupts.
 130  */
 131 static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
 132 {
 133         chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
 134         chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
 135 }
 136
 137 /*
 138  * This function restores the register configuration of the GPIO device.
 139  */
 140 static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
 141 {
 142         /* to store contents of PO register */
 143         iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
 144         /* to store contents of PM register */
 145         iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
 146 }
 147
 148 static void pch_gpio_setup(struct pch_gpio *chip)
 149 {
 150         struct gpio_chip *gpio = &chip->gpio;
 151
 152         gpio->label = dev_name(chip->dev);
 153         gpio->owner = THIS_MODULE;
 154         gpio->direction_input = pch_gpio_direction_input;
 155         gpio->get = pch_gpio_get;
 156         gpio->direction_output = pch_gpio_direction_output;
 157         gpio->set = pch_gpio_set;
 158         gpio->dbg_show = NULL;
 159         gpio->base = -1;
 160         gpio->ngpio = GPIO_NUM_PINS;
 161         gpio->can_sleep = 0;
 162 }
 163
 164 static int __devinit pch_gpio_probe(struct pci_dev *pdev,
 165                                     const struct pci_device_id *id)
 166 {
 167         s32 ret;
 168         struct pch_gpio *chip;
 169
 170         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 171         if (chip == NULL)
 172                 return -ENOMEM;
 173
 174         chip->dev = &pdev->dev;
 175         ret = pci_enable_device(pdev);
 176         if (ret) {
 177                 dev_err(&pdev->dev, "%s : pci_enable_device FAILED", __func__);
 178                 goto err_pci_enable;
 179         }
 180
 181         ret = pci_request_regions(pdev, KBUILD_MODNAME);
 182         if (ret) {
 183                 dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
 184                 goto err_request_regions;
 185         }
 186
 187         chip->base = pci_iomap(pdev, 1, 0);
 188         if (chip->base == 0) {
 189                 dev_err(&pdev->dev, "%s : pci_iomap FAILED", __func__);
 190                 ret = -ENOMEM;
 191                 goto err_iomap;
 192         }
 193
 194         chip->reg = chip->base;
 195         pci_set_drvdata(pdev, chip);
 196         mutex_init(&chip->lock);
 197         pch_gpio_setup(chip);
 198         ret = gpiochip_add(&chip->gpio);
 199         if (ret) {
 200                 dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
 201                 goto err_gpiochip_add;
 202         }
 203
 204         return 0;
 205
 206 err_gpiochip_add:
 207         pci_iounmap(pdev, chip->base);
 208
 209 err_iomap:
 210         pci_release_regions(pdev);
 211
 212 err_request_regions:
 213         pci_disable_device(pdev);
 214
 215 err_pci_enable:
 216         kfree(chip);
 217         dev_err(&pdev->dev, "%s Failed returns %d\n", __func__, ret);
 218         return ret;
 219 }
 220
 221 static void __devexit pch_gpio_remove(struct pci_dev *pdev)
 222 {
 223         int err;
 224         struct pch_gpio *chip = pci_get_drvdata(pdev);
 225
 226         err = gpiochip_remove(&chip->gpio);
 227         if (err)
 228                 dev_err(&pdev->dev, "Failed gpiochip_remove\n");
 229
 230         pci_iounmap(pdev, chip->base);
 231         pci_release_regions(pdev);
 232         pci_disable_device(pdev);
 233         kfree(chip);
 234 }
 235
 236 #ifdef CONFIG_PM
 237 static int pch_gpio_suspend(struct pci_dev *pdev, pm_message_t state)
 238 {
 239         s32 ret;
 240         struct pch_gpio *chip = pci_get_drvdata(pdev);
 241
 242         pch_gpio_save_reg_conf(chip);
 243         pch_gpio_restore_reg_conf(chip);
 244
 245         ret = pci_save_state(pdev);
 246         if (ret) {
 247                 dev_err(&pdev->dev, "pci_save_state Failed-%d\n", ret);
 248                 return ret;
 249         }
 250         pci_disable_device(pdev);
 251         pci_set_power_state(pdev, PCI_D0);
 252         ret = pci_enable_wake(pdev, PCI_D0, 1);
 253         if (ret)
 254                 dev_err(&pdev->dev, "pci_enable_wake Failed -%d\n", ret);
 255
 256         return 0;
 257 }
 258
 259 static int pch_gpio_resume(struct pci_dev *pdev)
 260 {
 261         s32 ret;
 262         struct pch_gpio *chip = pci_get_drvdata(pdev);
 263
 264         ret = pci_enable_wake(pdev, PCI_D0, 0);
 265
 266         pci_set_power_state(pdev, PCI_D0);
 267         ret = pci_enable_device(pdev);
 268         if (ret) {
 269                 dev_err(&pdev->dev, "pci_enable_device Failed-%d ", ret);
 270                 return ret;
 271         }
 272         pci_restore_state(pdev);
 273
 274         iowrite32(0x01, &chip->reg->reset);
 275         iowrite32(0x00, &chip->reg->reset);
 276         pch_gpio_restore_reg_conf(chip);
 277
 278         return 0;
 279 }
 280 #else
 281 #define pch_gpio_suspend NULL
 282 #define pch_gpio_resume NULL
 283 #endif
 284
 285 static DEFINE_PCI_DEVICE_TABLE(pch_gpio_pcidev_id) = {
 286         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
 287         { 0, }
 288 };
 289
 290 static struct pci_driver pch_gpio_driver = {
 291         .name = "pch_gpio",
 292         .id_table = pch_gpio_pcidev_id,
 293         .probe = pch_gpio_probe,
 294         .remove = __devexit_p(pch_gpio_remove),
 295         .suspend = pch_gpio_suspend,
 296         .resume = pch_gpio_resume
 297 };
 298
 299 static int __init pch_gpio_pci_init(void)
 300 {
 301         return pci_register_driver(&pch_gpio_driver);
 302 }
 303 module_init(pch_gpio_pci_init);
 304
 305 static void __exit pch_gpio_pci_exit(void)
 306 {
 307         pci_unregister_driver(&pch_gpio_driver);
 308 }
 309 module_exit(pch_gpio_pci_exit);
 310
 311 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
 312 MODULE_LICENSE("GPL");