drivers/gpio/gpio-intel-mid.c

   1 /*
   2  * Intel MID GPIO driver
   3  *
   4  * Copyright (c) 2008-2014,2016 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
  16 /* Supports:
  17  * Moorestown platform Langwell chip.
  18  * Medfield platform Penwell chip.
  19  * Clovertrail platform Cloverview chip.
  20  */
  21
  22 #include <linux/delay.h>
  23 #include <linux/init.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/io.h>
  26 #include <linux/gpio/driver.h>
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/pci.h>
  30 #include <linux/platform_device.h>
  31 #include <linux/pm_runtime.h>
  32 #include <linux/slab.h>
  33 #include <linux/stddef.h>
  34
  35 #define INTEL_MID_IRQ_TYPE_EDGE         (1 << 0)
  36 #define INTEL_MID_IRQ_TYPE_LEVEL        (1 << 1)
  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         GAFR,           /* alt function */
  61 };
  62
  63 /* intel_mid gpio driver data */
  64 struct intel_mid_gpio_ddata {
  65         u16 ngpio;              /* number of gpio pins */
  66         u32 chip_irq_type;      /* chip interrupt type */
  67 };
  68
  69 struct intel_mid_gpio {
  70         struct gpio_chip                chip;
  71         void __iomem                    *reg_base;
  72         spinlock_t                      lock;
  73         struct pci_dev                  *pdev;
  74 };
  75
  76 static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
  77                               enum GPIO_REG reg_type)
  78 {
  79         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
  80         unsigned nreg = chip->ngpio / 32;
  81         u8 reg = offset / 32;
  82
  83         return priv->reg_base + reg_type * nreg * 4 + reg * 4;
  84 }
  85
  86 static void __iomem *gpio_reg_2bit(struct gpio_chip *chip, unsigned offset,
  87                                    enum GPIO_REG reg_type)
  88 {
  89         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
  90         unsigned nreg = chip->ngpio / 32;
  91         u8 reg = offset / 16;
  92
  93         return priv->reg_base + reg_type * nreg * 4 + reg * 4;
  94 }
  95
  96 static int intel_gpio_request(struct gpio_chip *chip, unsigned offset)
  97 {
  98         void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
  99         u32 value = readl(gafr);
 100         int shift = (offset % 16) << 1, af = (value >> shift) & 3;
 101
 102         if (af) {
 103                 value &= ~(3 << shift);
 104                 writel(value, gafr);
 105         }
 106         return 0;
 107 }
 108
 109 static int intel_gpio_get(struct gpio_chip *chip, unsigned offset)
 110 {
 111         void __iomem *gplr = gpio_reg(chip, offset, GPLR);
 112
 113         return !!(readl(gplr) & BIT(offset % 32));
 114 }
 115
 116 static void intel_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 117 {
 118         void __iomem *gpsr, *gpcr;
 119
 120         if (value) {
 121                 gpsr = gpio_reg(chip, offset, GPSR);
 122                 writel(BIT(offset % 32), gpsr);
 123         } else {
 124                 gpcr = gpio_reg(chip, offset, GPCR);
 125                 writel(BIT(offset % 32), gpcr);
 126         }
 127 }
 128
 129 static int intel_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 130 {
 131         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
 132         void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 133         u32 value;
 134         unsigned long flags;
 135
 136         if (priv->pdev)
 137                 pm_runtime_get(&priv->pdev->dev);
 138
 139         spin_lock_irqsave(&priv->lock, flags);
 140         value = readl(gpdr);
 141         value &= ~BIT(offset % 32);
 142         writel(value, gpdr);
 143         spin_unlock_irqrestore(&priv->lock, flags);
 144
 145         if (priv->pdev)
 146                 pm_runtime_put(&priv->pdev->dev);
 147
 148         return 0;
 149 }
 150
 151 static int intel_gpio_direction_output(struct gpio_chip *chip,
 152                         unsigned offset, int value)
 153 {
 154         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
 155         void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 156         unsigned long flags;
 157
 158         intel_gpio_set(chip, offset, value);
 159
 160         if (priv->pdev)
 161                 pm_runtime_get(&priv->pdev->dev);
 162
 163         spin_lock_irqsave(&priv->lock, flags);
 164         value = readl(gpdr);
 165         value |= BIT(offset % 32);
 166         writel(value, gpdr);
 167         spin_unlock_irqrestore(&priv->lock, flags);
 168
 169         if (priv->pdev)
 170                 pm_runtime_put(&priv->pdev->dev);
 171
 172         return 0;
 173 }
 174
 175 static int intel_mid_irq_type(struct irq_data *d, unsigned type)
 176 {
 177         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 178         struct intel_mid_gpio *priv = gpiochip_get_data(gc);
 179         u32 gpio = irqd_to_hwirq(d);
 180         unsigned long flags;
 181         u32 value;
 182         void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
 183         void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
 184
 185         if (gpio >= priv->chip.ngpio)
 186                 return -EINVAL;
 187
 188         if (priv->pdev)
 189                 pm_runtime_get(&priv->pdev->dev);
 190
 191         spin_lock_irqsave(&priv->lock, flags);
 192         if (type & IRQ_TYPE_EDGE_RISING)
 193                 value = readl(grer) | BIT(gpio % 32);
 194         else
 195                 value = readl(grer) & (~BIT(gpio % 32));
 196         writel(value, grer);
 197
 198         if (type & IRQ_TYPE_EDGE_FALLING)
 199                 value = readl(gfer) | BIT(gpio % 32);
 200         else
 201                 value = readl(gfer) & (~BIT(gpio % 32));
 202         writel(value, gfer);
 203         spin_unlock_irqrestore(&priv->lock, flags);
 204
 205         if (priv->pdev)
 206                 pm_runtime_put(&priv->pdev->dev);
 207
 208         return 0;
 209 }
 210
 211 static void intel_mid_irq_unmask(struct irq_data *d)
 212 {
 213 }
 214
 215 static void intel_mid_irq_mask(struct irq_data *d)
 216 {
 217 }
 218
 219 static struct irq_chip intel_mid_irqchip = {
 220         .name           = "INTEL_MID-GPIO",
 221         .irq_mask       = intel_mid_irq_mask,
 222         .irq_unmask     = intel_mid_irq_unmask,
 223         .irq_set_type   = intel_mid_irq_type,
 224 };
 225
 226 static const struct intel_mid_gpio_ddata gpio_lincroft = {
 227         .ngpio = 64,
 228 };
 229
 230 static const struct intel_mid_gpio_ddata gpio_penwell_aon = {
 231         .ngpio = 96,
 232         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 233 };
 234
 235 static const struct intel_mid_gpio_ddata gpio_penwell_core = {
 236         .ngpio = 96,
 237         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 238 };
 239
 240 static const struct intel_mid_gpio_ddata gpio_cloverview_aon = {
 241         .ngpio = 96,
 242         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE | INTEL_MID_IRQ_TYPE_LEVEL,
 243 };
 244
 245 static const struct intel_mid_gpio_ddata gpio_cloverview_core = {
 246         .ngpio = 96,
 247         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 248 };
 249
 250 static const struct pci_device_id intel_gpio_ids[] = {
 251         {
 252                 /* Lincroft */
 253                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f),
 254                 .driver_data = (kernel_ulong_t)&gpio_lincroft,
 255         },
 256         {
 257                 /* Penwell AON */
 258                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f),
 259                 .driver_data = (kernel_ulong_t)&gpio_penwell_aon,
 260         },
 261         {
 262                 /* Penwell Core */
 263                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a),
 264                 .driver_data = (kernel_ulong_t)&gpio_penwell_core,
 265         },
 266         {
 267                 /* Cloverview Aon */
 268                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08eb),
 269                 .driver_data = (kernel_ulong_t)&gpio_cloverview_aon,
 270         },
 271         {
 272                 /* Cloverview Core */
 273                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08f7),
 274                 .driver_data = (kernel_ulong_t)&gpio_cloverview_core,
 275         },
 276         { 0 }
 277 };
 278 MODULE_DEVICE_TABLE(pci, intel_gpio_ids);
 279
 280 static void intel_mid_irq_handler(struct irq_desc *desc)
 281 {
 282         struct gpio_chip *gc = irq_desc_get_handler_data(desc);
 283         struct intel_mid_gpio *priv = gpiochip_get_data(gc);
 284         struct irq_data *data = irq_desc_get_irq_data(desc);
 285         struct irq_chip *chip = irq_data_get_irq_chip(data);
 286         u32 base, gpio, mask;
 287         unsigned long pending;
 288         void __iomem *gedr;
 289
 290         /* check GPIO controller to check which pin triggered the interrupt */
 291         for (base = 0; base < priv->chip.ngpio; base += 32) {
 292                 gedr = gpio_reg(&priv->chip, base, GEDR);
 293                 while ((pending = readl(gedr))) {
 294                         gpio = __ffs(pending);
 295                         mask = BIT(gpio);
 296                         /* Clear before handling so we can't lose an edge */
 297                         writel(mask, gedr);
 298                         generic_handle_irq(irq_find_mapping(gc->irqdomain,
 299                                                             base + gpio));
 300                 }
 301         }
 302
 303         chip->irq_eoi(data);
 304 }
 305
 306 static void intel_mid_irq_init_hw(struct intel_mid_gpio *priv)
 307 {
 308         void __iomem *reg;
 309         unsigned base;
 310
 311         for (base = 0; base < priv->chip.ngpio; base += 32) {
 312                 /* Clear the rising-edge detect register */
 313                 reg = gpio_reg(&priv->chip, base, GRER);
 314                 writel(0, reg);
 315                 /* Clear the falling-edge detect register */
 316                 reg = gpio_reg(&priv->chip, base, GFER);
 317                 writel(0, reg);
 318                 /* Clear the edge detect status register */
 319                 reg = gpio_reg(&priv->chip, base, GEDR);
 320                 writel(~0, reg);
 321         }
 322 }
 323
 324 static int intel_gpio_runtime_idle(struct device *dev)
 325 {
 326         int err = pm_schedule_suspend(dev, 500);
 327         return err ?: -EBUSY;
 328 }
 329
 330 static const struct dev_pm_ops intel_gpio_pm_ops = {
 331         SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle)
 332 };
 333
 334 static int intel_gpio_probe(struct pci_dev *pdev,
 335                           const struct pci_device_id *id)
 336 {
 337         void __iomem *base;
 338         struct intel_mid_gpio *priv;
 339         u32 gpio_base;
 340         u32 irq_base;
 341         int retval;
 342         struct intel_mid_gpio_ddata *ddata =
 343                                 (struct intel_mid_gpio_ddata *)id->driver_data;
 344
 345         retval = pcim_enable_device(pdev);
 346         if (retval)
 347                 return retval;
 348
 349         retval = pcim_iomap_regions(pdev, 1 << 0 | 1 << 1, pci_name(pdev));
 350         if (retval) {
 351                 dev_err(&pdev->dev, "I/O memory mapping error\n");
 352                 return retval;
 353         }
 354
 355         base = pcim_iomap_table(pdev)[1];
 356
 357         irq_base = readl(base);
 358         gpio_base = readl(sizeof(u32) + base);
 359
 360         /* release the IO mapping, since we already get the info from bar1 */
 361         pcim_iounmap_regions(pdev, 1 << 1);
 362
 363         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 364         if (!priv) {
 365                 dev_err(&pdev->dev, "can't allocate chip data\n");
 366                 return -ENOMEM;
 367         }
 368
 369         priv->reg_base = pcim_iomap_table(pdev)[0];
 370         priv->chip.label = dev_name(&pdev->dev);
 371         priv->chip.parent = &pdev->dev;
 372         priv->chip.request = intel_gpio_request;
 373         priv->chip.direction_input = intel_gpio_direction_input;
 374         priv->chip.direction_output = intel_gpio_direction_output;
 375         priv->chip.get = intel_gpio_get;
 376         priv->chip.set = intel_gpio_set;
 377         priv->chip.base = gpio_base;
 378         priv->chip.ngpio = ddata->ngpio;
 379         priv->chip.can_sleep = false;
 380         priv->pdev = pdev;
 381
 382         spin_lock_init(&priv->lock);
 383
 384         pci_set_drvdata(pdev, priv);
 385         retval = devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
 386         if (retval) {
 387                 dev_err(&pdev->dev, "gpiochip_add error %d\n", retval);
 388                 return retval;
 389         }
 390
 391         retval = gpiochip_irqchip_add(&priv->chip,
 392                                       &intel_mid_irqchip,
 393                                       irq_base,
 394                                       handle_simple_irq,
 395                                       IRQ_TYPE_NONE);
 396         if (retval) {
 397                 dev_err(&pdev->dev,
 398                         "could not connect irqchip to gpiochip\n");
 399                 return retval;
 400         }
 401
 402         intel_mid_irq_init_hw(priv);
 403
 404         gpiochip_set_chained_irqchip(&priv->chip,
 405                                      &intel_mid_irqchip,
 406                                      pdev->irq,
 407                                      intel_mid_irq_handler);
 408
 409         pm_runtime_put_noidle(&pdev->dev);
 410         pm_runtime_allow(&pdev->dev);
 411
 412         return 0;
 413 }
 414
 415 static struct pci_driver intel_gpio_driver = {
 416         .name           = "intel_mid_gpio",
 417         .id_table       = intel_gpio_ids,
 418         .probe          = intel_gpio_probe,
 419         .driver         = {
 420                 .pm     = &intel_gpio_pm_ops,
 421         },
 422 };
 423
 424 builtin_pci_driver(intel_gpio_driver);