linux/drivers/gpio/gpio-langwell.c
<<
>>
Prefs
   1/*
   2 * Moorestown platform Langwell chip GPIO driver
   3 *
   4 * Copyright (c) 2008 - 2009,  Intel Corporation.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 */
  19
  20/* Supports:
  21 * Moorestown platform Langwell chip.
  22 * Medfield platform Penwell chip.
  23 * Whitney point.
  24 */
  25
  26#include <linux/module.h>
  27#include <linux/pci.h>
  28#include <linux/platform_device.h>
  29#include <linux/kernel.h>
  30#include <linux/delay.h>
  31#include <linux/stddef.h>
  32#include <linux/interrupt.h>
  33#include <linux/init.h>
  34#include <linux/irq.h>
  35#include <linux/io.h>
  36#include <linux/gpio.h>
  37#include <linux/slab.h>
  38#include <linux/pm_runtime.h>
  39
  40/*
  41 * Langwell chip has 64 pins and thus there are 2 32bit registers to control
  42 * each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
  43 * registers to control them, so we only define the order here instead of a
  44 * structure, to get a bit offset for a pin (use GPDR as an example):
  45 *
  46 * nreg = ngpio / 32;
  47 * reg = offset / 32;
  48 * bit = offset % 32;
  49 * reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
  50 *
  51 * so the bit of reg_addr is to control pin offset's GPDR feature
  52*/
  53
  54enum GPIO_REG {
  55        GPLR = 0,       /* pin level read-only */
  56        GPDR,           /* pin direction */
  57        GPSR,           /* pin set */
  58        GPCR,           /* pin clear */
  59        GRER,           /* rising edge detect */
  60        GFER,           /* falling edge detect */
  61        GEDR,           /* edge detect result */
  62        GAFR,           /* alt function */
  63};
  64
  65struct lnw_gpio {
  66        struct gpio_chip                chip;
  67        void                            *reg_base;
  68        spinlock_t                      lock;
  69        unsigned                        irq_base;
  70        struct pci_dev                  *pdev;
  71};
  72
  73static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
  74                        enum GPIO_REG reg_type)
  75{
  76        struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
  77        unsigned nreg = chip->ngpio / 32;
  78        u8 reg = offset / 32;
  79        void __iomem *ptr;
  80
  81        ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
  82        return ptr;
  83}
  84
  85static void __iomem *gpio_reg_2bit(struct gpio_chip *chip, unsigned offset,
  86                                   enum GPIO_REG reg_type)
  87{
  88        struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
  89        unsigned nreg = chip->ngpio / 32;
  90        u8 reg = offset / 16;
  91        void __iomem *ptr;
  92
  93        ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
  94        return ptr;
  95}
  96
  97static int lnw_gpio_request(struct gpio_chip *chip, unsigned offset)
  98{
  99        void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
 100        u32 value = readl(gafr);
 101        int shift = (offset % 16) << 1, af = (value >> shift) & 3;
 102
 103        if (af) {
 104                value &= ~(3 << shift);
 105                writel(value, gafr);
 106        }
 107        return 0;
 108}
 109
 110static int lnw_gpio_get(struct gpio_chip *chip, unsigned offset)
 111{
 112        void __iomem *gplr = gpio_reg(chip, offset, GPLR);
 113
 114        return readl(gplr) & BIT(offset % 32);
 115}
 116
 117static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 118{
 119        void __iomem *gpsr, *gpcr;
 120
 121        if (value) {
 122                gpsr = gpio_reg(chip, offset, GPSR);
 123                writel(BIT(offset % 32), gpsr);
 124        } else {
 125                gpcr = gpio_reg(chip, offset, GPCR);
 126                writel(BIT(offset % 32), gpcr);
 127        }
 128}
 129
 130static int lnw_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 131{
 132        struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 133        void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 134        u32 value;
 135        unsigned long flags;
 136
 137        if (lnw->pdev)
 138                pm_runtime_get(&lnw->pdev->dev);
 139
 140        spin_lock_irqsave(&lnw->lock, flags);
 141        value = readl(gpdr);
 142        value &= ~BIT(offset % 32);
 143        writel(value, gpdr);
 144        spin_unlock_irqrestore(&lnw->lock, flags);
 145
 146        if (lnw->pdev)
 147                pm_runtime_put(&lnw->pdev->dev);
 148
 149        return 0;
 150}
 151
 152static int lnw_gpio_direction_output(struct gpio_chip *chip,
 153                        unsigned offset, int value)
 154{
 155        struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 156        void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 157        unsigned long flags;
 158
 159        lnw_gpio_set(chip, offset, value);
 160
 161        if (lnw->pdev)
 162                pm_runtime_get(&lnw->pdev->dev);
 163
 164        spin_lock_irqsave(&lnw->lock, flags);
 165        value = readl(gpdr);
 166        value |= BIT(offset % 32);
 167        writel(value, gpdr);
 168        spin_unlock_irqrestore(&lnw->lock, flags);
 169
 170        if (lnw->pdev)
 171                pm_runtime_put(&lnw->pdev->dev);
 172
 173        return 0;
 174}
 175
 176static int lnw_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 177{
 178        struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
 179        return lnw->irq_base + offset;
 180}
 181
 182static int lnw_irq_type(struct irq_data *d, unsigned type)
 183{
 184        struct lnw_gpio *lnw = irq_data_get_irq_chip_data(d);
 185        u32 gpio = d->irq - lnw->irq_base;
 186        unsigned long flags;
 187        u32 value;
 188        void __iomem *grer = gpio_reg(&lnw->chip, gpio, GRER);
 189        void __iomem *gfer = gpio_reg(&lnw->chip, gpio, GFER);
 190
 191        if (gpio >= lnw->chip.ngpio)
 192                return -EINVAL;
 193
 194        if (lnw->pdev)
 195                pm_runtime_get(&lnw->pdev->dev);
 196
 197        spin_lock_irqsave(&lnw->lock, flags);
 198        if (type & IRQ_TYPE_EDGE_RISING)
 199                value = readl(grer) | BIT(gpio % 32);
 200        else
 201                value = readl(grer) & (~BIT(gpio % 32));
 202        writel(value, grer);
 203
 204        if (type & IRQ_TYPE_EDGE_FALLING)
 205                value = readl(gfer) | BIT(gpio % 32);
 206        else
 207                value = readl(gfer) & (~BIT(gpio % 32));
 208        writel(value, gfer);
 209        spin_unlock_irqrestore(&lnw->lock, flags);
 210
 211        if (lnw->pdev)
 212                pm_runtime_put(&lnw->pdev->dev);
 213
 214        return 0;
 215}
 216
 217static void lnw_irq_unmask(struct irq_data *d)
 218{
 219}
 220
 221static void lnw_irq_mask(struct irq_data *d)
 222{
 223}
 224
 225static struct irq_chip lnw_irqchip = {
 226        .name           = "LNW-GPIO",
 227        .irq_mask       = lnw_irq_mask,
 228        .irq_unmask     = lnw_irq_unmask,
 229        .irq_set_type   = lnw_irq_type,
 230};
 231
 232static DEFINE_PCI_DEVICE_TABLE(lnw_gpio_ids) = {   /* pin number */
 233        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f), .driver_data = 64 },
 234        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f), .driver_data = 96 },
 235        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a), .driver_data = 96 },
 236        { 0, }
 237};
 238MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);
 239
 240static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
 241{
 242        struct irq_data *data = irq_desc_get_irq_data(desc);
 243        struct lnw_gpio *lnw = irq_data_get_irq_handler_data(data);
 244        struct irq_chip *chip = irq_data_get_irq_chip(data);
 245        u32 base, gpio, mask;
 246        unsigned long pending;
 247        void __iomem *gedr;
 248
 249        /* check GPIO controller to check which pin triggered the interrupt */
 250        for (base = 0; base < lnw->chip.ngpio; base += 32) {
 251                gedr = gpio_reg(&lnw->chip, base, GEDR);
 252                pending = readl(gedr);
 253                while (pending) {
 254                        gpio = __ffs(pending);
 255                        mask = BIT(gpio);
 256                        pending &= ~mask;
 257                        /* Clear before handling so we can't lose an edge */
 258                        writel(mask, gedr);
 259                        generic_handle_irq(lnw->irq_base + base + gpio);
 260                }
 261        }
 262
 263        chip->irq_eoi(data);
 264}
 265
 266#ifdef CONFIG_PM
 267static int lnw_gpio_runtime_resume(struct device *dev)
 268{
 269        return 0;
 270}
 271
 272static int lnw_gpio_runtime_suspend(struct device *dev)
 273{
 274        return 0;
 275}
 276
 277static int lnw_gpio_runtime_idle(struct device *dev)
 278{
 279        int err = pm_schedule_suspend(dev, 500);
 280
 281        if (!err)
 282                return 0;
 283
 284        return -EBUSY;
 285}
 286
 287#else
 288#define lnw_gpio_runtime_suspend        NULL
 289#define lnw_gpio_runtime_resume         NULL
 290#define lnw_gpio_runtime_idle           NULL
 291#endif
 292
 293static const struct dev_pm_ops lnw_gpio_pm_ops = {
 294        .runtime_suspend = lnw_gpio_runtime_suspend,
 295        .runtime_resume = lnw_gpio_runtime_resume,
 296        .runtime_idle = lnw_gpio_runtime_idle,
 297};
 298
 299static int __devinit lnw_gpio_probe(struct pci_dev *pdev,
 300                        const struct pci_device_id *id)
 301{
 302        void *base;
 303        int i;
 304        resource_size_t start, len;
 305        struct lnw_gpio *lnw;
 306        u32 irq_base;
 307        u32 gpio_base;
 308        int retval = 0;
 309
 310        retval = pci_enable_device(pdev);
 311        if (retval)
 312                goto done;
 313
 314        retval = pci_request_regions(pdev, "langwell_gpio");
 315        if (retval) {
 316                dev_err(&pdev->dev, "error requesting resources\n");
 317                goto err2;
 318        }
 319        /* get the irq_base from bar1 */
 320        start = pci_resource_start(pdev, 1);
 321        len = pci_resource_len(pdev, 1);
 322        base = ioremap_nocache(start, len);
 323        if (!base) {
 324                dev_err(&pdev->dev, "error mapping bar1\n");
 325                goto err3;
 326        }
 327        irq_base = *(u32 *)base;
 328        gpio_base = *((u32 *)base + 1);
 329        /* release the IO mapping, since we already get the info from bar1 */
 330        iounmap(base);
 331        /* get the register base from bar0 */
 332        start = pci_resource_start(pdev, 0);
 333        len = pci_resource_len(pdev, 0);
 334        base = ioremap_nocache(start, len);
 335        if (!base) {
 336                dev_err(&pdev->dev, "error mapping bar0\n");
 337                retval = -EFAULT;
 338                goto err3;
 339        }
 340
 341        lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
 342        if (!lnw) {
 343                dev_err(&pdev->dev, "can't allocate langwell_gpio chip data\n");
 344                retval = -ENOMEM;
 345                goto err4;
 346        }
 347        lnw->reg_base = base;
 348        lnw->irq_base = irq_base;
 349        lnw->chip.label = dev_name(&pdev->dev);
 350        lnw->chip.request = lnw_gpio_request;
 351        lnw->chip.direction_input = lnw_gpio_direction_input;
 352        lnw->chip.direction_output = lnw_gpio_direction_output;
 353        lnw->chip.get = lnw_gpio_get;
 354        lnw->chip.set = lnw_gpio_set;
 355        lnw->chip.to_irq = lnw_gpio_to_irq;
 356        lnw->chip.base = gpio_base;
 357        lnw->chip.ngpio = id->driver_data;
 358        lnw->chip.can_sleep = 0;
 359        lnw->pdev = pdev;
 360        pci_set_drvdata(pdev, lnw);
 361        retval = gpiochip_add(&lnw->chip);
 362        if (retval) {
 363                dev_err(&pdev->dev, "langwell gpiochip_add error %d\n", retval);
 364                goto err5;
 365        }
 366        irq_set_handler_data(pdev->irq, lnw);
 367        irq_set_chained_handler(pdev->irq, lnw_irq_handler);
 368        for (i = 0; i < lnw->chip.ngpio; i++) {
 369                irq_set_chip_and_handler_name(i + lnw->irq_base, &lnw_irqchip,
 370                                              handle_simple_irq, "demux");
 371                irq_set_chip_data(i + lnw->irq_base, lnw);
 372        }
 373
 374        spin_lock_init(&lnw->lock);
 375
 376        pm_runtime_put_noidle(&pdev->dev);
 377        pm_runtime_allow(&pdev->dev);
 378
 379        goto done;
 380err5:
 381        kfree(lnw);
 382err4:
 383        iounmap(base);
 384err3:
 385        pci_release_regions(pdev);
 386err2:
 387        pci_disable_device(pdev);
 388done:
 389        return retval;
 390}
 391
 392static struct pci_driver lnw_gpio_driver = {
 393        .name           = "langwell_gpio",
 394        .id_table       = lnw_gpio_ids,
 395        .probe          = lnw_gpio_probe,
 396        .driver         = {
 397                .pm     = &lnw_gpio_pm_ops,
 398        },
 399};
 400
 401
 402static int __devinit wp_gpio_probe(struct platform_device *pdev)
 403{
 404        struct lnw_gpio *lnw;
 405        struct gpio_chip *gc;
 406        struct resource *rc;
 407        int retval = 0;
 408
 409        rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 410        if (!rc)
 411                return -EINVAL;
 412
 413        lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
 414        if (!lnw) {
 415                dev_err(&pdev->dev,
 416                        "can't allocate whitneypoint_gpio chip data\n");
 417                return -ENOMEM;
 418        }
 419        lnw->reg_base = ioremap_nocache(rc->start, resource_size(rc));
 420        if (lnw->reg_base == NULL) {
 421                retval = -EINVAL;
 422                goto err_kmalloc;
 423        }
 424        spin_lock_init(&lnw->lock);
 425        gc = &lnw->chip;
 426        gc->label = dev_name(&pdev->dev);
 427        gc->owner = THIS_MODULE;
 428        gc->direction_input = lnw_gpio_direction_input;
 429        gc->direction_output = lnw_gpio_direction_output;
 430        gc->get = lnw_gpio_get;
 431        gc->set = lnw_gpio_set;
 432        gc->to_irq = NULL;
 433        gc->base = 0;
 434        gc->ngpio = 64;
 435        gc->can_sleep = 0;
 436        retval = gpiochip_add(gc);
 437        if (retval) {
 438                dev_err(&pdev->dev, "whitneypoint gpiochip_add error %d\n",
 439                                                                retval);
 440                goto err_ioremap;
 441        }
 442        platform_set_drvdata(pdev, lnw);
 443        return 0;
 444err_ioremap:
 445        iounmap(lnw->reg_base);
 446err_kmalloc:
 447        kfree(lnw);
 448        return retval;
 449}
 450
 451static int __devexit wp_gpio_remove(struct platform_device *pdev)
 452{
 453        struct lnw_gpio *lnw = platform_get_drvdata(pdev);
 454        int err;
 455        err = gpiochip_remove(&lnw->chip);
 456        if (err)
 457                dev_err(&pdev->dev, "failed to remove gpio_chip.\n");
 458        iounmap(lnw->reg_base);
 459        kfree(lnw);
 460        platform_set_drvdata(pdev, NULL);
 461        return 0;
 462}
 463
 464static struct platform_driver wp_gpio_driver = {
 465        .probe          = wp_gpio_probe,
 466        .remove         = __devexit_p(wp_gpio_remove),
 467        .driver         = {
 468                .name   = "wp_gpio",
 469                .owner  = THIS_MODULE,
 470        },
 471};
 472
 473static int __init lnw_gpio_init(void)
 474{
 475        int ret;
 476        ret =  pci_register_driver(&lnw_gpio_driver);
 477        if (ret < 0)
 478                return ret;
 479        ret = platform_driver_register(&wp_gpio_driver);
 480        if (ret < 0)
 481                pci_unregister_driver(&lnw_gpio_driver);
 482        return ret;
 483}
 484
 485device_initcall(lnw_gpio_init);
 486