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