linux/drivers/gpio/gpio-pch.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
   4 */
   5#include <linux/bits.h>
   6#include <linux/gpio/driver.h>
   7#include <linux/interrupt.h>
   8#include <linux/irq.h>
   9#include <linux/kernel.h>
  10#include <linux/module.h>
  11#include <linux/pci.h>
  12#include <linux/slab.h>
  13
  14#define PCH_EDGE_FALLING        0
  15#define PCH_EDGE_RISING         1
  16#define PCH_LEVEL_L             2
  17#define PCH_LEVEL_H             3
  18#define PCH_EDGE_BOTH           4
  19#define PCH_IM_MASK             GENMASK(2, 0)
  20
  21#define PCH_IRQ_BASE            24
  22
  23struct pch_regs {
  24        u32     ien;
  25        u32     istatus;
  26        u32     idisp;
  27        u32     iclr;
  28        u32     imask;
  29        u32     imaskclr;
  30        u32     po;
  31        u32     pi;
  32        u32     pm;
  33        u32     im0;
  34        u32     im1;
  35        u32     reserved[3];
  36        u32     gpio_use_sel;
  37        u32     reset;
  38};
  39
  40enum pch_type_t {
  41        INTEL_EG20T_PCH,
  42        OKISEMI_ML7223m_IOH, /* LAPIS Semiconductor ML7223 IOH PCIe Bus-m */
  43        OKISEMI_ML7223n_IOH  /* LAPIS Semiconductor ML7223 IOH PCIe Bus-n */
  44};
  45
  46/* Specifies number of GPIO PINS */
  47static int gpio_pins[] = {
  48        [INTEL_EG20T_PCH] = 12,
  49        [OKISEMI_ML7223m_IOH] = 8,
  50        [OKISEMI_ML7223n_IOH] = 8,
  51};
  52
  53/**
  54 * struct pch_gpio_reg_data - The register store data.
  55 * @ien_reg:    To store contents of IEN register.
  56 * @imask_reg:  To store contents of IMASK register.
  57 * @po_reg:     To store contents of PO register.
  58 * @pm_reg:     To store contents of PM register.
  59 * @im0_reg:    To store contents of IM0 register.
  60 * @im1_reg:    To store contents of IM1 register.
  61 * @gpio_use_sel_reg : To store contents of GPIO_USE_SEL register.
  62 *                     (Only ML7223 Bus-n)
  63 */
  64struct pch_gpio_reg_data {
  65        u32 ien_reg;
  66        u32 imask_reg;
  67        u32 po_reg;
  68        u32 pm_reg;
  69        u32 im0_reg;
  70        u32 im1_reg;
  71        u32 gpio_use_sel_reg;
  72};
  73
  74/**
  75 * struct pch_gpio - GPIO private data structure.
  76 * @base:                       PCI base address of Memory mapped I/O register.
  77 * @reg:                        Memory mapped PCH GPIO register list.
  78 * @dev:                        Pointer to device structure.
  79 * @gpio:                       Data for GPIO infrastructure.
  80 * @pch_gpio_reg:               Memory mapped Register data is saved here
  81 *                              when suspend.
  82 * @lock:                       Used for register access protection
  83 * @irq_base:           Save base of IRQ number for interrupt
  84 * @ioh:                IOH ID
  85 * @spinlock:           Used for register access protection
  86 */
  87struct pch_gpio {
  88        void __iomem *base;
  89        struct pch_regs __iomem *reg;
  90        struct device *dev;
  91        struct gpio_chip gpio;
  92        struct pch_gpio_reg_data pch_gpio_reg;
  93        int irq_base;
  94        enum pch_type_t ioh;
  95        spinlock_t spinlock;
  96};
  97
  98static void pch_gpio_set(struct gpio_chip *gpio, unsigned int nr, int val)
  99{
 100        u32 reg_val;
 101        struct pch_gpio *chip = gpiochip_get_data(gpio);
 102        unsigned long flags;
 103
 104        spin_lock_irqsave(&chip->spinlock, flags);
 105        reg_val = ioread32(&chip->reg->po);
 106        if (val)
 107                reg_val |= BIT(nr);
 108        else
 109                reg_val &= ~BIT(nr);
 110
 111        iowrite32(reg_val, &chip->reg->po);
 112        spin_unlock_irqrestore(&chip->spinlock, flags);
 113}
 114
 115static int pch_gpio_get(struct gpio_chip *gpio, unsigned int nr)
 116{
 117        struct pch_gpio *chip = gpiochip_get_data(gpio);
 118
 119        return !!(ioread32(&chip->reg->pi) & BIT(nr));
 120}
 121
 122static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned int nr,
 123                                     int val)
 124{
 125        struct pch_gpio *chip = gpiochip_get_data(gpio);
 126        u32 pm;
 127        u32 reg_val;
 128        unsigned long flags;
 129
 130        spin_lock_irqsave(&chip->spinlock, flags);
 131
 132        reg_val = ioread32(&chip->reg->po);
 133        if (val)
 134                reg_val |= BIT(nr);
 135        else
 136                reg_val &= ~BIT(nr);
 137        iowrite32(reg_val, &chip->reg->po);
 138
 139        pm = ioread32(&chip->reg->pm);
 140        pm &= BIT(gpio_pins[chip->ioh]) - 1;
 141        pm |= BIT(nr);
 142        iowrite32(pm, &chip->reg->pm);
 143
 144        spin_unlock_irqrestore(&chip->spinlock, flags);
 145
 146        return 0;
 147}
 148
 149static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned int nr)
 150{
 151        struct pch_gpio *chip = gpiochip_get_data(gpio);
 152        u32 pm;
 153        unsigned long flags;
 154
 155        spin_lock_irqsave(&chip->spinlock, flags);
 156        pm = ioread32(&chip->reg->pm);
 157        pm &= BIT(gpio_pins[chip->ioh]) - 1;
 158        pm &= ~BIT(nr);
 159        iowrite32(pm, &chip->reg->pm);
 160        spin_unlock_irqrestore(&chip->spinlock, flags);
 161
 162        return 0;
 163}
 164
 165/*
 166 * Save register configuration and disable interrupts.
 167 */
 168static void __maybe_unused pch_gpio_save_reg_conf(struct pch_gpio *chip)
 169{
 170        chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
 171        chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
 172        chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
 173        chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
 174        chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
 175        if (chip->ioh == INTEL_EG20T_PCH)
 176                chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
 177        if (chip->ioh == OKISEMI_ML7223n_IOH)
 178                chip->pch_gpio_reg.gpio_use_sel_reg = ioread32(&chip->reg->gpio_use_sel);
 179}
 180
 181/*
 182 * This function restores the register configuration of the GPIO device.
 183 */
 184static void __maybe_unused pch_gpio_restore_reg_conf(struct pch_gpio *chip)
 185{
 186        iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
 187        iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
 188        /* to store contents of PO register */
 189        iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
 190        /* to store contents of PM register */
 191        iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
 192        iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
 193        if (chip->ioh == INTEL_EG20T_PCH)
 194                iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
 195        if (chip->ioh == OKISEMI_ML7223n_IOH)
 196                iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg, &chip->reg->gpio_use_sel);
 197}
 198
 199static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned int offset)
 200{
 201        struct pch_gpio *chip = gpiochip_get_data(gpio);
 202
 203        return chip->irq_base + offset;
 204}
 205
 206static void pch_gpio_setup(struct pch_gpio *chip)
 207{
 208        struct gpio_chip *gpio = &chip->gpio;
 209
 210        gpio->label = dev_name(chip->dev);
 211        gpio->parent = chip->dev;
 212        gpio->owner = THIS_MODULE;
 213        gpio->direction_input = pch_gpio_direction_input;
 214        gpio->get = pch_gpio_get;
 215        gpio->direction_output = pch_gpio_direction_output;
 216        gpio->set = pch_gpio_set;
 217        gpio->base = -1;
 218        gpio->ngpio = gpio_pins[chip->ioh];
 219        gpio->can_sleep = false;
 220        gpio->to_irq = pch_gpio_to_irq;
 221}
 222
 223static int pch_irq_type(struct irq_data *d, unsigned int type)
 224{
 225        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 226        struct pch_gpio *chip = gc->private;
 227        u32 im, im_pos, val;
 228        u32 __iomem *im_reg;
 229        unsigned long flags;
 230        int ch, irq = d->irq;
 231
 232        ch = irq - chip->irq_base;
 233        if (irq < chip->irq_base + 8) {
 234                im_reg = &chip->reg->im0;
 235                im_pos = ch - 0;
 236        } else {
 237                im_reg = &chip->reg->im1;
 238                im_pos = ch - 8;
 239        }
 240        dev_dbg(chip->dev, "irq=%d type=%d ch=%d pos=%d\n", irq, type, ch, im_pos);
 241
 242        switch (type) {
 243        case IRQ_TYPE_EDGE_RISING:
 244                val = PCH_EDGE_RISING;
 245                break;
 246        case IRQ_TYPE_EDGE_FALLING:
 247                val = PCH_EDGE_FALLING;
 248                break;
 249        case IRQ_TYPE_EDGE_BOTH:
 250                val = PCH_EDGE_BOTH;
 251                break;
 252        case IRQ_TYPE_LEVEL_HIGH:
 253                val = PCH_LEVEL_H;
 254                break;
 255        case IRQ_TYPE_LEVEL_LOW:
 256                val = PCH_LEVEL_L;
 257                break;
 258        default:
 259                return 0;
 260        }
 261
 262        spin_lock_irqsave(&chip->spinlock, flags);
 263
 264        /* Set interrupt mode */
 265        im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
 266        iowrite32(im | (val << (im_pos * 4)), im_reg);
 267
 268        /* And the handler */
 269        if (type & IRQ_TYPE_LEVEL_MASK)
 270                irq_set_handler_locked(d, handle_level_irq);
 271        else if (type & IRQ_TYPE_EDGE_BOTH)
 272                irq_set_handler_locked(d, handle_edge_irq);
 273
 274        spin_unlock_irqrestore(&chip->spinlock, flags);
 275        return 0;
 276}
 277
 278static void pch_irq_unmask(struct irq_data *d)
 279{
 280        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 281        struct pch_gpio *chip = gc->private;
 282
 283        iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imaskclr);
 284}
 285
 286static void pch_irq_mask(struct irq_data *d)
 287{
 288        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 289        struct pch_gpio *chip = gc->private;
 290
 291        iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->imask);
 292}
 293
 294static void pch_irq_ack(struct irq_data *d)
 295{
 296        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 297        struct pch_gpio *chip = gc->private;
 298
 299        iowrite32(BIT(d->irq - chip->irq_base), &chip->reg->iclr);
 300}
 301
 302static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
 303{
 304        struct pch_gpio *chip = dev_id;
 305        unsigned long reg_val = ioread32(&chip->reg->istatus);
 306        int i;
 307
 308        dev_vdbg(chip->dev, "irq=%d  status=0x%lx\n", irq, reg_val);
 309
 310        reg_val &= BIT(gpio_pins[chip->ioh]) - 1;
 311
 312        for_each_set_bit(i, &reg_val, gpio_pins[chip->ioh])
 313                generic_handle_irq(chip->irq_base + i);
 314
 315        return IRQ_RETVAL(reg_val);
 316}
 317
 318static int pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
 319                                       unsigned int irq_start,
 320                                       unsigned int num)
 321{
 322        struct irq_chip_generic *gc;
 323        struct irq_chip_type *ct;
 324        int rv;
 325
 326        gc = devm_irq_alloc_generic_chip(chip->dev, "pch_gpio", 1, irq_start,
 327                                         chip->base, handle_simple_irq);
 328        if (!gc)
 329                return -ENOMEM;
 330
 331        gc->private = chip;
 332        ct = gc->chip_types;
 333
 334        ct->chip.irq_ack = pch_irq_ack;
 335        ct->chip.irq_mask = pch_irq_mask;
 336        ct->chip.irq_unmask = pch_irq_unmask;
 337        ct->chip.irq_set_type = pch_irq_type;
 338
 339        rv = devm_irq_setup_generic_chip(chip->dev, gc, IRQ_MSK(num),
 340                                         IRQ_GC_INIT_MASK_CACHE,
 341                                         IRQ_NOREQUEST | IRQ_NOPROBE, 0);
 342
 343        return rv;
 344}
 345
 346static int pch_gpio_probe(struct pci_dev *pdev,
 347                                    const struct pci_device_id *id)
 348{
 349        s32 ret;
 350        struct pch_gpio *chip;
 351        int irq_base;
 352
 353        chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
 354        if (chip == NULL)
 355                return -ENOMEM;
 356
 357        chip->dev = &pdev->dev;
 358        ret = pcim_enable_device(pdev);
 359        if (ret) {
 360                dev_err(&pdev->dev, "pci_enable_device FAILED");
 361                return ret;
 362        }
 363
 364        ret = pcim_iomap_regions(pdev, BIT(1), KBUILD_MODNAME);
 365        if (ret) {
 366                dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
 367                return ret;
 368        }
 369
 370        chip->base = pcim_iomap_table(pdev)[1];
 371
 372        if (pdev->device == 0x8803)
 373                chip->ioh = INTEL_EG20T_PCH;
 374        else if (pdev->device == 0x8014)
 375                chip->ioh = OKISEMI_ML7223m_IOH;
 376        else if (pdev->device == 0x8043)
 377                chip->ioh = OKISEMI_ML7223n_IOH;
 378
 379        chip->reg = chip->base;
 380        pci_set_drvdata(pdev, chip);
 381        spin_lock_init(&chip->spinlock);
 382        pch_gpio_setup(chip);
 383
 384        ret = devm_gpiochip_add_data(&pdev->dev, &chip->gpio, chip);
 385        if (ret) {
 386                dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
 387                return ret;
 388        }
 389
 390        irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0,
 391                                        gpio_pins[chip->ioh], NUMA_NO_NODE);
 392        if (irq_base < 0) {
 393                dev_warn(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
 394                chip->irq_base = -1;
 395                return 0;
 396        }
 397        chip->irq_base = irq_base;
 398
 399        /* Mask all interrupts, but enable them */
 400        iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->imask);
 401        iowrite32(BIT(gpio_pins[chip->ioh]) - 1, &chip->reg->ien);
 402
 403        ret = devm_request_irq(&pdev->dev, pdev->irq, pch_gpio_handler,
 404                               IRQF_SHARED, KBUILD_MODNAME, chip);
 405        if (ret) {
 406                dev_err(&pdev->dev, "request_irq failed\n");
 407                return ret;
 408        }
 409
 410        return pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
 411}
 412
 413static int __maybe_unused pch_gpio_suspend(struct device *dev)
 414{
 415        struct pch_gpio *chip = dev_get_drvdata(dev);
 416        unsigned long flags;
 417
 418        spin_lock_irqsave(&chip->spinlock, flags);
 419        pch_gpio_save_reg_conf(chip);
 420        spin_unlock_irqrestore(&chip->spinlock, flags);
 421
 422        return 0;
 423}
 424
 425static int __maybe_unused pch_gpio_resume(struct device *dev)
 426{
 427        struct pch_gpio *chip = dev_get_drvdata(dev);
 428        unsigned long flags;
 429
 430        spin_lock_irqsave(&chip->spinlock, flags);
 431        iowrite32(0x01, &chip->reg->reset);
 432        iowrite32(0x00, &chip->reg->reset);
 433        pch_gpio_restore_reg_conf(chip);
 434        spin_unlock_irqrestore(&chip->spinlock, flags);
 435
 436        return 0;
 437}
 438
 439static SIMPLE_DEV_PM_OPS(pch_gpio_pm_ops, pch_gpio_suspend, pch_gpio_resume);
 440
 441static const struct pci_device_id pch_gpio_pcidev_id[] = {
 442        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
 443        { PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
 444        { PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043) },
 445        { PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803) },
 446        { 0, }
 447};
 448MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
 449
 450static struct pci_driver pch_gpio_driver = {
 451        .name = "pch_gpio",
 452        .id_table = pch_gpio_pcidev_id,
 453        .probe = pch_gpio_probe,
 454        .driver = {
 455                .pm = &pch_gpio_pm_ops,
 456        },
 457};
 458
 459module_pci_driver(pch_gpio_driver);
 460
 461MODULE_DESCRIPTION("PCH GPIO PCI Driver");
 462MODULE_LICENSE("GPL v2");
 463