drivers/gpio/langwell_gpio.c

   1 /* langwell_gpio.c Moorestown platform Langwell chip GPIO driver
   2  * Copyright (c) 2008 - 2009,  Intel Corporation.
   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 version 2 as
   6  * published by the Free Software Foundation.
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
  16  */
  17
  18 /* Supports:
  19  * Moorestown platform Langwell chip.
  20  * Medfield platform Penwell chip.
  21  * Whitney point.
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/pci.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/kernel.h>
  28 #include <linux/delay.h>
  29 #include <linux/stddef.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/init.h>
  32 #include <linux/irq.h>
  33 #include <linux/io.h>
  34 #include <linux/gpio.h>
  35 #include <linux/slab.h>
  36 #include <linux/pm_runtime.h>
  37
  38 /*
  39  * Langwell chip has 64 pins and thus there are 2 32bit registers to control
  40  * each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
  41  * registers to control them, so we only define the order here instead of a
  42  * structure, to get a bit offset for a pin (use GPDR as an example):
  43  *
  44  * nreg = ngpio / 32;
  45  * reg = offset / 32;
  46  * bit = offset % 32;
  47  * reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
  48  *
  49  * so the bit of reg_addr is to control pin offset's GPDR feature
  50 */
  51
  52 enum GPIO_REG {
  53         GPLR = 0,       /* pin level read-only */
  54         GPDR,           /* pin direction */
  55         GPSR,           /* pin set */
  56         GPCR,           /* pin clear */
  57         GRER,           /* rising edge detect */
  58         GFER,           /* falling edge detect */
  59         GEDR,           /* edge detect result */
  60 };
  61
  62 struct lnw_gpio {
  63         struct gpio_chip                chip;
  64         void                            *reg_base;
  65         spinlock_t                      lock;
  66         unsigned                        irq_base;
  67         struct pci_dev                  *pdev;
  68 };
  69
  70 static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
  71                         enum GPIO_REG reg_type)
  72 {
  73         struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
  74         unsigned nreg = chip->ngpio / 32;
  75         u8 reg = offset / 32;
  76         void __iomem *ptr;
  77
  78         ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
  79         return ptr;
  80 }
  81
  82 static int lnw_gpio_get(struct gpio_chip *chip, unsigned offset)
  83 {
  84         void __iomem *gplr = gpio_reg(chip, offset, GPLR);
  85
  86         return readl(gplr) & BIT(offset % 32);
  87 }
  88
  89 static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  90 {
  91         void __iomem *gpsr, *gpcr;
  92
  93         if (value) {
  94                 gpsr = gpio_reg(chip, offset, GPSR);
  95                 writel(BIT(offset % 32), gpsr);
  96         } else {
  97                 gpcr = gpio_reg(chip, offset, GPCR);
  98                 writel(BIT(offset % 32), gpcr);
  99         }
 100 }
 101
 102 static int lnw_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 103 {
 104         struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 105         void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 106         u32 value;
 107         unsigned long flags;
 108
 109         if (lnw->pdev)
 110                 pm_runtime_get(&lnw->pdev->dev);
 111
 112         spin_lock_irqsave(&lnw->lock, flags);
 113         value = readl(gpdr);
 114         value &= ~BIT(offset % 32);
 115         writel(value, gpdr);
 116         spin_unlock_irqrestore(&lnw->lock, flags);
 117
 118         if (lnw->pdev)
 119                 pm_runtime_put(&lnw->pdev->dev);
 120
 121         return 0;
 122 }
 123
 124 static int lnw_gpio_direction_output(struct gpio_chip *chip,
 125                         unsigned offset, int value)
 126 {
 127         struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 128         void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 129         unsigned long flags;
 130
 131         lnw_gpio_set(chip, offset, value);
 132
 133         if (lnw->pdev)
 134                 pm_runtime_get(&lnw->pdev->dev);
 135
 136         spin_lock_irqsave(&lnw->lock, flags);
 137         value = readl(gpdr);
 138         value |= BIT(offset % 32);
 139         writel(value, gpdr);
 140         spin_unlock_irqrestore(&lnw->lock, flags);
 141
 142         if (lnw->pdev)
 143                 pm_runtime_put(&lnw->pdev->dev);
 144
 145         return 0;
 146 }
 147
 148 static int lnw_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 149 {
 150         struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 151         return lnw->irq_base + offset;
 152 }
 153
 154 static int lnw_irq_type(struct irq_data *d, unsigned type)
 155 {
 156         struct lnw_gpio *lnw = irq_data_get_irq_chip_data(d);
 157         u32 gpio = d->irq - lnw->irq_base;
 158         unsigned long flags;
 159         u32 value;
 160         void __iomem *grer = gpio_reg(&lnw->chip, gpio, GRER);
 161         void __iomem *gfer = gpio_reg(&lnw->chip, gpio, GFER);
 162
 163         if (gpio >= lnw->chip.ngpio)
 164                 return -EINVAL;
 165
 166         if (lnw->pdev)
 167                 pm_runtime_get(&lnw->pdev->dev);
 168
 169         spin_lock_irqsave(&lnw->lock, flags);
 170         if (type & IRQ_TYPE_EDGE_RISING)
 171                 value = readl(grer) | BIT(gpio % 32);
 172         else
 173                 value = readl(grer) & (~BIT(gpio % 32));
 174         writel(value, grer);
 175
 176         if (type & IRQ_TYPE_EDGE_FALLING)
 177                 value = readl(gfer) | BIT(gpio % 32);
 178         else
 179                 value = readl(gfer) & (~BIT(gpio % 32));
 180         writel(value, gfer);
 181         spin_unlock_irqrestore(&lnw->lock, flags);
 182
 183         if (lnw->pdev)
 184                 pm_runtime_put(&lnw->pdev->dev);
 185
 186         return 0;
 187 }
 188
 189 static void lnw_irq_unmask(struct irq_data *d)
 190 {
 191 }
 192
 193 static void lnw_irq_mask(struct irq_data *d)
 194 {
 195 }
 196
 197 static struct irq_chip lnw_irqchip = {
 198         .name           = "LNW-GPIO",
 199         .irq_mask       = lnw_irq_mask,
 200         .irq_unmask     = lnw_irq_unmask,
 201         .irq_set_type   = lnw_irq_type,
 202 };
 203
 204 static DEFINE_PCI_DEVICE_TABLE(lnw_gpio_ids) = {   /* pin number */
 205         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f), .driver_data = 64 },
 206         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f), .driver_data = 96 },
 207         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a), .driver_data = 96 },
 208         { 0, }
 209 };
 210 MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);
 211
 212 static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
 213 {
 214         struct irq_data *data = irq_desc_get_irq_data(desc);
 215         struct lnw_gpio *lnw = irq_data_get_irq_handler_data(data);
 216         struct irq_chip *chip = irq_data_get_irq_chip(data);
 217         u32 base, gpio, mask;
 218         unsigned long pending;
 219         void __iomem *gedr;
 220
 221         /* check GPIO controller to check which pin triggered the interrupt */
 222         for (base = 0; base < lnw->chip.ngpio; base += 32) {
 223                 gedr = gpio_reg(&lnw->chip, base, GEDR);
 224                 pending = readl(gedr);
 225                 while (pending) {
 226                         gpio = __ffs(pending) - 1;
 227                         mask = BIT(gpio);
 228                         pending &= ~mask;
 229                         /* Clear before handling so we can't lose an edge */
 230                         writel(mask, gedr);
 231                         generic_handle_irq(lnw->irq_base + base + gpio);
 232                 }
 233         }
 234
 235         chip->irq_eoi(data);
 236 }
 237
 238 #ifdef CONFIG_PM
 239 static int lnw_gpio_runtime_resume(struct device *dev)
 240 {
 241         return 0;
 242 }
 243
 244 static int lnw_gpio_runtime_suspend(struct device *dev)
 245 {
 246         return 0;
 247 }
 248
 249 static int lnw_gpio_runtime_idle(struct device *dev)
 250 {
 251         int err = pm_schedule_suspend(dev, 500);
 252
 253         if (!err)
 254                 return 0;
 255
 256         return -EBUSY;
 257 }
 258
 259 #else
 260 #define lnw_gpio_runtime_suspend        NULL
 261 #define lnw_gpio_runtime_resume         NULL
 262 #define lnw_gpio_runtime_idle           NULL
 263 #endif
 264
 265 static const struct dev_pm_ops lnw_gpio_pm_ops = {
 266         .runtime_suspend = lnw_gpio_runtime_suspend,
 267         .runtime_resume = lnw_gpio_runtime_resume,
 268         .runtime_idle = lnw_gpio_runtime_idle,
 269 };
 270
 271 static int __devinit lnw_gpio_probe(struct pci_dev *pdev,
 272                         const struct pci_device_id *id)
 273 {
 274         void *base;
 275         int i;
 276         resource_size_t start, len;
 277         struct lnw_gpio *lnw;
 278         u32 irq_base;
 279         u32 gpio_base;
 280         int retval = 0;
 281
 282         retval = pci_enable_device(pdev);
 283         if (retval)
 284                 goto done;
 285
 286         retval = pci_request_regions(pdev, "langwell_gpio");
 287         if (retval) {
 288                 dev_err(&pdev->dev, "error requesting resources\n");
 289                 goto err2;
 290         }
 291         /* get the irq_base from bar1 */
 292         start = pci_resource_start(pdev, 1);
 293         len = pci_resource_len(pdev, 1);
 294         base = ioremap_nocache(start, len);
 295         if (!base) {
 296                 dev_err(&pdev->dev, "error mapping bar1\n");
 297                 goto err3;
 298         }
 299         irq_base = *(u32 *)base;
 300         gpio_base = *((u32 *)base + 1);
 301         /* release the IO mapping, since we already get the info from bar1 */
 302         iounmap(base);
 303         /* get the register base from bar0 */
 304         start = pci_resource_start(pdev, 0);
 305         len = pci_resource_len(pdev, 0);
 306         base = ioremap_nocache(start, len);
 307         if (!base) {
 308                 dev_err(&pdev->dev, "error mapping bar0\n");
 309                 retval = -EFAULT;
 310                 goto err3;
 311         }
 312
 313         lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
 314         if (!lnw) {
 315                 dev_err(&pdev->dev, "can't allocate langwell_gpio chip data\n");
 316                 retval = -ENOMEM;
 317                 goto err4;
 318         }
 319         lnw->reg_base = base;
 320         lnw->irq_base = irq_base;
 321         lnw->chip.label = dev_name(&pdev->dev);
 322         lnw->chip.direction_input = lnw_gpio_direction_input;
 323         lnw->chip.direction_output = lnw_gpio_direction_output;
 324         lnw->chip.get = lnw_gpio_get;
 325         lnw->chip.set = lnw_gpio_set;
 326         lnw->chip.to_irq = lnw_gpio_to_irq;
 327         lnw->chip.base = gpio_base;
 328         lnw->chip.ngpio = id->driver_data;
 329         lnw->chip.can_sleep = 0;
 330         lnw->pdev = pdev;
 331         pci_set_drvdata(pdev, lnw);
 332         retval = gpiochip_add(&lnw->chip);
 333         if (retval) {
 334                 dev_err(&pdev->dev, "langwell gpiochip_add error %d\n", retval);
 335                 goto err5;
 336         }
 337         irq_set_handler_data(pdev->irq, lnw);
 338         irq_set_chained_handler(pdev->irq, lnw_irq_handler);
 339         for (i = 0; i < lnw->chip.ngpio; i++) {
 340                 irq_set_chip_and_handler_name(i + lnw->irq_base, &lnw_irqchip,
 341                                               handle_simple_irq, "demux");
 342                 irq_set_chip_data(i + lnw->irq_base, lnw);
 343         }
 344
 345         spin_lock_init(&lnw->lock);
 346
 347         pm_runtime_put_noidle(&pdev->dev);
 348         pm_runtime_allow(&pdev->dev);
 349
 350         goto done;
 351 err5:
 352         kfree(lnw);
 353 err4:
 354         iounmap(base);
 355 err3:
 356         pci_release_regions(pdev);
 357 err2:
 358         pci_disable_device(pdev);
 359 done:
 360         return retval;
 361 }
 362
 363 static struct pci_driver lnw_gpio_driver = {
 364         .name           = "langwell_gpio",
 365         .id_table       = lnw_gpio_ids,
 366         .probe          = lnw_gpio_probe,
 367         .driver         = {
 368                 .pm     = &lnw_gpio_pm_ops,
 369         },
 370 };
 371
 372
 373 static int __devinit wp_gpio_probe(struct platform_device *pdev)
 374 {
 375         struct lnw_gpio *lnw;
 376         struct gpio_chip *gc;
 377         struct resource *rc;
 378         int retval = 0;
 379
 380         rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 381         if (!rc)
 382                 return -EINVAL;
 383
 384         lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
 385         if (!lnw) {
 386                 dev_err(&pdev->dev,
 387                         "can't allocate whitneypoint_gpio chip data\n");
 388                 return -ENOMEM;
 389         }
 390         lnw->reg_base = ioremap_nocache(rc->start, resource_size(rc));
 391         if (lnw->reg_base == NULL) {
 392                 retval = -EINVAL;
 393                 goto err_kmalloc;
 394         }
 395         spin_lock_init(&lnw->lock);
 396         gc = &lnw->chip;
 397         gc->label = dev_name(&pdev->dev);
 398         gc->owner = THIS_MODULE;
 399         gc->direction_input = lnw_gpio_direction_input;
 400         gc->direction_output = lnw_gpio_direction_output;
 401         gc->get = lnw_gpio_get;
 402         gc->set = lnw_gpio_set;
 403         gc->to_irq = NULL;
 404         gc->base = 0;
 405         gc->ngpio = 64;
 406         gc->can_sleep = 0;
 407         retval = gpiochip_add(gc);
 408         if (retval) {
 409                 dev_err(&pdev->dev, "whitneypoint gpiochip_add error %d\n",
 410                                                                 retval);
 411                 goto err_ioremap;
 412         }
 413         platform_set_drvdata(pdev, lnw);
 414         return 0;
 415 err_ioremap:
 416         iounmap(lnw->reg_base);
 417 err_kmalloc:
 418         kfree(lnw);
 419         return retval;
 420 }
 421
 422 static int __devexit wp_gpio_remove(struct platform_device *pdev)
 423 {
 424         struct lnw_gpio *lnw = platform_get_drvdata(pdev);
 425         int err;
 426         err = gpiochip_remove(&lnw->chip);
 427         if (err)
 428                 dev_err(&pdev->dev, "failed to remove gpio_chip.\n");
 429         iounmap(lnw->reg_base);
 430         kfree(lnw);
 431         platform_set_drvdata(pdev, NULL);
 432         return 0;
 433 }
 434
 435 static struct platform_driver wp_gpio_driver = {
 436         .probe          = wp_gpio_probe,
 437         .remove         = __devexit_p(wp_gpio_remove),
 438         .driver         = {
 439                 .name   = "wp_gpio",
 440                 .owner  = THIS_MODULE,
 441         },
 442 };
 443
 444 static int __init lnw_gpio_init(void)
 445 {
 446         int ret;
 447         ret =  pci_register_driver(&lnw_gpio_driver);
 448         if (ret < 0)
 449                 return ret;
 450         ret = platform_driver_register(&wp_gpio_driver);
 451         if (ret < 0)
 452                 pci_unregister_driver(&lnw_gpio_driver);
 453         return ret;
 454 }
 455
 456 device_initcall(lnw_gpio_init);