drivers/gpio/gpio-intel-mid.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Intel MID GPIO driver
   4  *
   5  * Copyright (c) 2008-2014,2016 Intel Corporation.
   6  */
   7
   8 /* Supports:
   9  * Moorestown platform Langwell chip.
  10  * Medfield platform Penwell chip.
  11  * Clovertrail platform Cloverview chip.
  12  */
  13
  14 #include <linux/delay.h>
  15 #include <linux/gpio/driver.h>
  16 #include <linux/init.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/io.h>
  19 #include <linux/kernel.h>
  20 #include <linux/pci.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/pm_runtime.h>
  23 #include <linux/slab.h>
  24 #include <linux/stddef.h>
  25
  26 #define INTEL_MID_IRQ_TYPE_EDGE         (1 << 0)
  27 #define INTEL_MID_IRQ_TYPE_LEVEL        (1 << 1)
  28
  29 /*
  30  * Langwell chip has 64 pins and thus there are 2 32bit registers to control
  31  * each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
  32  * registers to control them, so we only define the order here instead of a
  33  * structure, to get a bit offset for a pin (use GPDR as an example):
  34  *
  35  * nreg = ngpio / 32;
  36  * reg = offset / 32;
  37  * bit = offset % 32;
  38  * reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
  39  *
  40  * so the bit of reg_addr is to control pin offset's GPDR feature
  41 */
  42
  43 enum GPIO_REG {
  44         GPLR = 0,       /* pin level read-only */
  45         GPDR,           /* pin direction */
  46         GPSR,           /* pin set */
  47         GPCR,           /* pin clear */
  48         GRER,           /* rising edge detect */
  49         GFER,           /* falling edge detect */
  50         GEDR,           /* edge detect result */
  51         GAFR,           /* alt function */
  52 };
  53
  54 /* intel_mid gpio driver data */
  55 struct intel_mid_gpio_ddata {
  56         u16 ngpio;              /* number of gpio pins */
  57         u32 chip_irq_type;      /* chip interrupt type */
  58 };
  59
  60 struct intel_mid_gpio {
  61         struct gpio_chip                chip;
  62         void __iomem                    *reg_base;
  63         spinlock_t                      lock;
  64         struct pci_dev                  *pdev;
  65 };
  66
  67 static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
  68                               enum GPIO_REG reg_type)
  69 {
  70         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
  71         unsigned nreg = chip->ngpio / 32;
  72         u8 reg = offset / 32;
  73
  74         return priv->reg_base + reg_type * nreg * 4 + reg * 4;
  75 }
  76
  77 static void __iomem *gpio_reg_2bit(struct gpio_chip *chip, unsigned offset,
  78                                    enum GPIO_REG reg_type)
  79 {
  80         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
  81         unsigned nreg = chip->ngpio / 32;
  82         u8 reg = offset / 16;
  83
  84         return priv->reg_base + reg_type * nreg * 4 + reg * 4;
  85 }
  86
  87 static int intel_gpio_request(struct gpio_chip *chip, unsigned offset)
  88 {
  89         void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
  90         u32 value = readl(gafr);
  91         int shift = (offset % 16) << 1, af = (value >> shift) & 3;
  92
  93         if (af) {
  94                 value &= ~(3 << shift);
  95                 writel(value, gafr);
  96         }
  97         return 0;
  98 }
  99
 100 static int intel_gpio_get(struct gpio_chip *chip, unsigned offset)
 101 {
 102         void __iomem *gplr = gpio_reg(chip, offset, GPLR);
 103
 104         return !!(readl(gplr) & BIT(offset % 32));
 105 }
 106
 107 static void intel_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 108 {
 109         void __iomem *gpsr, *gpcr;
 110
 111         if (value) {
 112                 gpsr = gpio_reg(chip, offset, GPSR);
 113                 writel(BIT(offset % 32), gpsr);
 114         } else {
 115                 gpcr = gpio_reg(chip, offset, GPCR);
 116                 writel(BIT(offset % 32), gpcr);
 117         }
 118 }
 119
 120 static int intel_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 121 {
 122         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
 123         void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 124         u32 value;
 125         unsigned long flags;
 126
 127         if (priv->pdev)
 128                 pm_runtime_get(&priv->pdev->dev);
 129
 130         spin_lock_irqsave(&priv->lock, flags);
 131         value = readl(gpdr);
 132         value &= ~BIT(offset % 32);
 133         writel(value, gpdr);
 134         spin_unlock_irqrestore(&priv->lock, flags);
 135
 136         if (priv->pdev)
 137                 pm_runtime_put(&priv->pdev->dev);
 138
 139         return 0;
 140 }
 141
 142 static int intel_gpio_direction_output(struct gpio_chip *chip,
 143                         unsigned offset, int value)
 144 {
 145         struct intel_mid_gpio *priv = gpiochip_get_data(chip);
 146         void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
 147         unsigned long flags;
 148
 149         intel_gpio_set(chip, offset, value);
 150
 151         if (priv->pdev)
 152                 pm_runtime_get(&priv->pdev->dev);
 153
 154         spin_lock_irqsave(&priv->lock, flags);
 155         value = readl(gpdr);
 156         value |= BIT(offset % 32);
 157         writel(value, gpdr);
 158         spin_unlock_irqrestore(&priv->lock, flags);
 159
 160         if (priv->pdev)
 161                 pm_runtime_put(&priv->pdev->dev);
 162
 163         return 0;
 164 }
 165
 166 static int intel_mid_irq_type(struct irq_data *d, unsigned type)
 167 {
 168         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
 169         struct intel_mid_gpio *priv = gpiochip_get_data(gc);
 170         u32 gpio = irqd_to_hwirq(d);
 171         unsigned long flags;
 172         u32 value;
 173         void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
 174         void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
 175
 176         if (gpio >= priv->chip.ngpio)
 177                 return -EINVAL;
 178
 179         if (priv->pdev)
 180                 pm_runtime_get(&priv->pdev->dev);
 181
 182         spin_lock_irqsave(&priv->lock, flags);
 183         if (type & IRQ_TYPE_EDGE_RISING)
 184                 value = readl(grer) | BIT(gpio % 32);
 185         else
 186                 value = readl(grer) & (~BIT(gpio % 32));
 187         writel(value, grer);
 188
 189         if (type & IRQ_TYPE_EDGE_FALLING)
 190                 value = readl(gfer) | BIT(gpio % 32);
 191         else
 192                 value = readl(gfer) & (~BIT(gpio % 32));
 193         writel(value, gfer);
 194         spin_unlock_irqrestore(&priv->lock, flags);
 195
 196         if (priv->pdev)
 197                 pm_runtime_put(&priv->pdev->dev);
 198
 199         return 0;
 200 }
 201
 202 static void intel_mid_irq_unmask(struct irq_data *d)
 203 {
 204 }
 205
 206 static void intel_mid_irq_mask(struct irq_data *d)
 207 {
 208 }
 209
 210 static struct irq_chip intel_mid_irqchip = {
 211         .name           = "INTEL_MID-GPIO",
 212         .irq_mask       = intel_mid_irq_mask,
 213         .irq_unmask     = intel_mid_irq_unmask,
 214         .irq_set_type   = intel_mid_irq_type,
 215 };
 216
 217 static const struct intel_mid_gpio_ddata gpio_lincroft = {
 218         .ngpio = 64,
 219 };
 220
 221 static const struct intel_mid_gpio_ddata gpio_penwell_aon = {
 222         .ngpio = 96,
 223         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 224 };
 225
 226 static const struct intel_mid_gpio_ddata gpio_penwell_core = {
 227         .ngpio = 96,
 228         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 229 };
 230
 231 static const struct intel_mid_gpio_ddata gpio_cloverview_aon = {
 232         .ngpio = 96,
 233         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE | INTEL_MID_IRQ_TYPE_LEVEL,
 234 };
 235
 236 static const struct intel_mid_gpio_ddata gpio_cloverview_core = {
 237         .ngpio = 96,
 238         .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
 239 };
 240
 241 static const struct pci_device_id intel_gpio_ids[] = {
 242         {
 243                 /* Lincroft */
 244                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f),
 245                 .driver_data = (kernel_ulong_t)&gpio_lincroft,
 246         },
 247         {
 248                 /* Penwell AON */
 249                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f),
 250                 .driver_data = (kernel_ulong_t)&gpio_penwell_aon,
 251         },
 252         {
 253                 /* Penwell Core */
 254                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a),
 255                 .driver_data = (kernel_ulong_t)&gpio_penwell_core,
 256         },
 257         {
 258                 /* Cloverview Aon */
 259                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08eb),
 260                 .driver_data = (kernel_ulong_t)&gpio_cloverview_aon,
 261         },
 262         {
 263                 /* Cloverview Core */
 264                 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08f7),
 265                 .driver_data = (kernel_ulong_t)&gpio_cloverview_core,
 266         },
 267         { }
 268 };
 269
 270 static void intel_mid_irq_handler(struct irq_desc *desc)
 271 {
 272         struct gpio_chip *gc = irq_desc_get_handler_data(desc);
 273         struct intel_mid_gpio *priv = gpiochip_get_data(gc);
 274         struct irq_data *data = irq_desc_get_irq_data(desc);
 275         struct irq_chip *chip = irq_data_get_irq_chip(data);
 276         u32 base, gpio, mask;
 277         unsigned long pending;
 278         void __iomem *gedr;
 279
 280         /* check GPIO controller to check which pin triggered the interrupt */
 281         for (base = 0; base < priv->chip.ngpio; base += 32) {
 282                 gedr = gpio_reg(&priv->chip, base, GEDR);
 283                 while ((pending = readl(gedr))) {
 284                         gpio = __ffs(pending);
 285                         mask = BIT(gpio);
 286                         /* Clear before handling so we can't lose an edge */
 287                         writel(mask, gedr);
 288                         generic_handle_irq(irq_find_mapping(gc->irq.domain,
 289                                                             base + gpio));
 290                 }
 291         }
 292
 293         chip->irq_eoi(data);
 294 }
 295
 296 static void intel_mid_irq_init_hw(struct intel_mid_gpio *priv)
 297 {
 298         void __iomem *reg;
 299         unsigned base;
 300
 301         for (base = 0; base < priv->chip.ngpio; base += 32) {
 302                 /* Clear the rising-edge detect register */
 303                 reg = gpio_reg(&priv->chip, base, GRER);
 304                 writel(0, reg);
 305                 /* Clear the falling-edge detect register */
 306                 reg = gpio_reg(&priv->chip, base, GFER);
 307                 writel(0, reg);
 308                 /* Clear the edge detect status register */
 309                 reg = gpio_reg(&priv->chip, base, GEDR);
 310                 writel(~0, reg);
 311         }
 312 }
 313
 314 static int __maybe_unused intel_gpio_runtime_idle(struct device *dev)
 315 {
 316         int err = pm_schedule_suspend(dev, 500);
 317         return err ?: -EBUSY;
 318 }
 319
 320 static const struct dev_pm_ops intel_gpio_pm_ops = {
 321         SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle)
 322 };
 323
 324 static int intel_gpio_probe(struct pci_dev *pdev,
 325                           const struct pci_device_id *id)
 326 {
 327         void __iomem *base;
 328         struct intel_mid_gpio *priv;
 329         u32 gpio_base;
 330         u32 irq_base;
 331         int retval;
 332         struct intel_mid_gpio_ddata *ddata =
 333                                 (struct intel_mid_gpio_ddata *)id->driver_data;
 334
 335         retval = pcim_enable_device(pdev);
 336         if (retval)
 337                 return retval;
 338
 339         retval = pcim_iomap_regions(pdev, 1 << 0 | 1 << 1, pci_name(pdev));
 340         if (retval) {
 341                 dev_err(&pdev->dev, "I/O memory mapping error\n");
 342                 return retval;
 343         }
 344
 345         base = pcim_iomap_table(pdev)[1];
 346
 347         irq_base = readl(base);
 348         gpio_base = readl(sizeof(u32) + base);
 349
 350         /* release the IO mapping, since we already get the info from bar1 */
 351         pcim_iounmap_regions(pdev, 1 << 1);
 352
 353         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 354         if (!priv)
 355                 return -ENOMEM;
 356
 357         priv->reg_base = pcim_iomap_table(pdev)[0];
 358         priv->chip.label = dev_name(&pdev->dev);
 359         priv->chip.parent = &pdev->dev;
 360         priv->chip.request = intel_gpio_request;
 361         priv->chip.direction_input = intel_gpio_direction_input;
 362         priv->chip.direction_output = intel_gpio_direction_output;
 363         priv->chip.get = intel_gpio_get;
 364         priv->chip.set = intel_gpio_set;
 365         priv->chip.base = gpio_base;
 366         priv->chip.ngpio = ddata->ngpio;
 367         priv->chip.can_sleep = false;
 368         priv->pdev = pdev;
 369
 370         spin_lock_init(&priv->lock);
 371
 372         pci_set_drvdata(pdev, priv);
 373         retval = devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
 374         if (retval) {
 375                 dev_err(&pdev->dev, "gpiochip_add error %d\n", retval);
 376                 return retval;
 377         }
 378
 379         retval = gpiochip_irqchip_add(&priv->chip,
 380                                       &intel_mid_irqchip,
 381                                       irq_base,
 382                                       handle_simple_irq,
 383                                       IRQ_TYPE_NONE);
 384         if (retval) {
 385                 dev_err(&pdev->dev,
 386                         "could not connect irqchip to gpiochip\n");
 387                 return retval;
 388         }
 389
 390         intel_mid_irq_init_hw(priv);
 391
 392         gpiochip_set_chained_irqchip(&priv->chip,
 393                                      &intel_mid_irqchip,
 394                                      pdev->irq,
 395                                      intel_mid_irq_handler);
 396
 397         pm_runtime_put_noidle(&pdev->dev);
 398         pm_runtime_allow(&pdev->dev);
 399
 400         return 0;
 401 }
 402
 403 static struct pci_driver intel_gpio_driver = {
 404         .name           = "intel_mid_gpio",
 405         .id_table       = intel_gpio_ids,
 406         .probe          = intel_gpio_probe,
 407         .driver         = {
 408                 .pm     = &intel_gpio_pm_ops,
 409         },
 410 };
 411
 412 builtin_pci_driver(intel_gpio_driver);