linux/drivers/gpio/gpio-xlp.c
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   1/*
   2 * Copyright (C) 2003-2015 Broadcom Corporation
   3 * All Rights Reserved
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License version 2 as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 */
  14
  15#include <linux/gpio.h>
  16#include <linux/platform_device.h>
  17#include <linux/of_device.h>
  18#include <linux/module.h>
  19#include <linux/irq.h>
  20#include <linux/interrupt.h>
  21#include <linux/irqchip/chained_irq.h>
  22
  23/*
  24 * XLP GPIO has multiple 32 bit registers for each feature where each register
  25 * controls 32 pins. So, pins up to 64 require 2 32-bit registers and up to 96
  26 * require 3 32-bit registers for each feature.
  27 * Here we only define offset of the first register for each feature. Offset of
  28 * the registers for pins greater than 32 can be calculated as following(Use
  29 * GPIO_INT_STAT as example):
  30 *
  31 * offset = (gpio / XLP_GPIO_REGSZ) * 4;
  32 * reg_addr = addr + offset;
  33 *
  34 * where addr is base address of the that feature register and gpio is the pin.
  35 */
  36#define GPIO_OUTPUT_EN          0x00
  37#define GPIO_PADDRV             0x08
  38#define GPIO_INT_EN00           0x18
  39#define GPIO_INT_EN10           0x20
  40#define GPIO_INT_EN20           0x28
  41#define GPIO_INT_EN30           0x30
  42#define GPIO_INT_POL            0x38
  43#define GPIO_INT_TYPE           0x40
  44#define GPIO_INT_STAT           0x48
  45
  46#define GPIO_9XX_BYTESWAP       0X00
  47#define GPIO_9XX_CTRL           0X04
  48#define GPIO_9XX_OUTPUT_EN      0x14
  49#define GPIO_9XX_PADDRV         0x24
  50/*
  51 * Only for 4 interrupt enable reg are defined for now,
  52 * total reg available are 12.
  53 */
  54#define GPIO_9XX_INT_EN00       0x44
  55#define GPIO_9XX_INT_EN10       0x54
  56#define GPIO_9XX_INT_EN20       0x64
  57#define GPIO_9XX_INT_EN30       0x74
  58#define GPIO_9XX_INT_POL        0x104
  59#define GPIO_9XX_INT_TYPE       0x114
  60#define GPIO_9XX_INT_STAT       0x124
  61
  62#define GPIO_3XX_INT_EN00       0x18
  63#define GPIO_3XX_INT_EN10       0x20
  64#define GPIO_3XX_INT_EN20       0x28
  65#define GPIO_3XX_INT_EN30       0x30
  66#define GPIO_3XX_INT_POL        0x78
  67#define GPIO_3XX_INT_TYPE       0x80
  68#define GPIO_3XX_INT_STAT       0x88
  69
  70/* Interrupt type register mask */
  71#define XLP_GPIO_IRQ_TYPE_LVL   0x0
  72#define XLP_GPIO_IRQ_TYPE_EDGE  0x1
  73
  74/* Interrupt polarity register mask */
  75#define XLP_GPIO_IRQ_POL_HIGH   0x0
  76#define XLP_GPIO_IRQ_POL_LOW    0x1
  77
  78#define XLP_GPIO_REGSZ          32
  79#define XLP_GPIO_IRQ_BASE       768
  80#define XLP_MAX_NR_GPIO         96
  81
  82/* XLP variants supported by this driver */
  83enum {
  84        XLP_GPIO_VARIANT_XLP832 = 1,
  85        XLP_GPIO_VARIANT_XLP316,
  86        XLP_GPIO_VARIANT_XLP208,
  87        XLP_GPIO_VARIANT_XLP980,
  88        XLP_GPIO_VARIANT_XLP532
  89};
  90
  91struct xlp_gpio_priv {
  92        struct gpio_chip chip;
  93        DECLARE_BITMAP(gpio_enabled_mask, XLP_MAX_NR_GPIO);
  94        void __iomem *gpio_intr_en;     /* pointer to first intr enable reg */
  95        void __iomem *gpio_intr_stat;   /* pointer to first intr status reg */
  96        void __iomem *gpio_intr_type;   /* pointer to first intr type reg */
  97        void __iomem *gpio_intr_pol;    /* pointer to first intr polarity reg */
  98        void __iomem *gpio_out_en;      /* pointer to first output enable reg */
  99        void __iomem *gpio_paddrv;      /* pointer to first pad drive reg */
 100        spinlock_t lock;
 101};
 102
 103static int xlp_gpio_get_reg(void __iomem *addr, unsigned gpio)
 104{
 105        u32 pos, regset;
 106
 107        pos = gpio % XLP_GPIO_REGSZ;
 108        regset = (gpio / XLP_GPIO_REGSZ) * 4;
 109        return !!(readl(addr + regset) & BIT(pos));
 110}
 111
 112static void xlp_gpio_set_reg(void __iomem *addr, unsigned gpio, int state)
 113{
 114        u32 value, pos, regset;
 115
 116        pos = gpio % XLP_GPIO_REGSZ;
 117        regset = (gpio / XLP_GPIO_REGSZ) * 4;
 118        value = readl(addr + regset);
 119
 120        if (state)
 121                value |= BIT(pos);
 122        else
 123                value &= ~BIT(pos);
 124
 125        writel(value, addr + regset);
 126}
 127
 128static void xlp_gpio_irq_disable(struct irq_data *d)
 129{
 130        struct gpio_chip *gc  = irq_data_get_irq_chip_data(d);
 131        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 132        unsigned long flags;
 133
 134        spin_lock_irqsave(&priv->lock, flags);
 135        xlp_gpio_set_reg(priv->gpio_intr_en, d->hwirq, 0x0);
 136        __clear_bit(d->hwirq, priv->gpio_enabled_mask);
 137        spin_unlock_irqrestore(&priv->lock, flags);
 138}
 139
 140static void xlp_gpio_irq_mask_ack(struct irq_data *d)
 141{
 142        struct gpio_chip *gc  = irq_data_get_irq_chip_data(d);
 143        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 144        unsigned long flags;
 145
 146        spin_lock_irqsave(&priv->lock, flags);
 147        xlp_gpio_set_reg(priv->gpio_intr_en, d->hwirq, 0x0);
 148        xlp_gpio_set_reg(priv->gpio_intr_stat, d->hwirq, 0x1);
 149        __clear_bit(d->hwirq, priv->gpio_enabled_mask);
 150        spin_unlock_irqrestore(&priv->lock, flags);
 151}
 152
 153static void xlp_gpio_irq_unmask(struct irq_data *d)
 154{
 155        struct gpio_chip *gc  = irq_data_get_irq_chip_data(d);
 156        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 157        unsigned long flags;
 158
 159        spin_lock_irqsave(&priv->lock, flags);
 160        xlp_gpio_set_reg(priv->gpio_intr_en, d->hwirq, 0x1);
 161        __set_bit(d->hwirq, priv->gpio_enabled_mask);
 162        spin_unlock_irqrestore(&priv->lock, flags);
 163}
 164
 165static int xlp_gpio_set_irq_type(struct irq_data *d, unsigned int type)
 166{
 167        struct gpio_chip *gc  = irq_data_get_irq_chip_data(d);
 168        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 169        int pol, irq_type;
 170
 171        switch (type) {
 172        case IRQ_TYPE_EDGE_RISING:
 173                irq_type = XLP_GPIO_IRQ_TYPE_EDGE;
 174                pol = XLP_GPIO_IRQ_POL_HIGH;
 175                break;
 176        case IRQ_TYPE_EDGE_FALLING:
 177                irq_type = XLP_GPIO_IRQ_TYPE_EDGE;
 178                pol = XLP_GPIO_IRQ_POL_LOW;
 179                break;
 180        case IRQ_TYPE_LEVEL_HIGH:
 181                irq_type = XLP_GPIO_IRQ_TYPE_LVL;
 182                pol = XLP_GPIO_IRQ_POL_HIGH;
 183                break;
 184        case IRQ_TYPE_LEVEL_LOW:
 185                irq_type = XLP_GPIO_IRQ_TYPE_LVL;
 186                pol = XLP_GPIO_IRQ_POL_LOW;
 187                break;
 188        default:
 189                return -EINVAL;
 190        }
 191
 192        xlp_gpio_set_reg(priv->gpio_intr_type, d->hwirq, irq_type);
 193        xlp_gpio_set_reg(priv->gpio_intr_pol, d->hwirq, pol);
 194
 195        return 0;
 196}
 197
 198static struct irq_chip xlp_gpio_irq_chip = {
 199        .name           = "XLP-GPIO",
 200        .irq_mask_ack   = xlp_gpio_irq_mask_ack,
 201        .irq_disable    = xlp_gpio_irq_disable,
 202        .irq_set_type   = xlp_gpio_set_irq_type,
 203        .irq_unmask     = xlp_gpio_irq_unmask,
 204        .flags          = IRQCHIP_ONESHOT_SAFE,
 205};
 206
 207static void xlp_gpio_generic_handler(struct irq_desc *desc)
 208{
 209        struct xlp_gpio_priv *priv = irq_desc_get_handler_data(desc);
 210        struct irq_chip *irqchip = irq_desc_get_chip(desc);
 211        int gpio, regoff;
 212        u32 gpio_stat;
 213
 214        regoff = -1;
 215        gpio_stat = 0;
 216
 217        chained_irq_enter(irqchip, desc);
 218        for_each_set_bit(gpio, priv->gpio_enabled_mask, XLP_MAX_NR_GPIO) {
 219                if (regoff != gpio / XLP_GPIO_REGSZ) {
 220                        regoff = gpio / XLP_GPIO_REGSZ;
 221                        gpio_stat = readl(priv->gpio_intr_stat + regoff * 4);
 222                }
 223
 224                if (gpio_stat & BIT(gpio % XLP_GPIO_REGSZ))
 225                        generic_handle_irq(irq_find_mapping(
 226                                                priv->chip.irqdomain, gpio));
 227        }
 228        chained_irq_exit(irqchip, desc);
 229}
 230
 231static int xlp_gpio_dir_output(struct gpio_chip *gc, unsigned gpio, int state)
 232{
 233        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 234
 235        BUG_ON(gpio >= gc->ngpio);
 236        xlp_gpio_set_reg(priv->gpio_out_en, gpio, 0x1);
 237
 238        return 0;
 239}
 240
 241static int xlp_gpio_dir_input(struct gpio_chip *gc, unsigned gpio)
 242{
 243        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 244
 245        BUG_ON(gpio >= gc->ngpio);
 246        xlp_gpio_set_reg(priv->gpio_out_en, gpio, 0x0);
 247
 248        return 0;
 249}
 250
 251static int xlp_gpio_get(struct gpio_chip *gc, unsigned gpio)
 252{
 253        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 254
 255        BUG_ON(gpio >= gc->ngpio);
 256        return xlp_gpio_get_reg(priv->gpio_paddrv, gpio);
 257}
 258
 259static void xlp_gpio_set(struct gpio_chip *gc, unsigned gpio, int state)
 260{
 261        struct xlp_gpio_priv *priv = gpiochip_get_data(gc);
 262
 263        BUG_ON(gpio >= gc->ngpio);
 264        xlp_gpio_set_reg(priv->gpio_paddrv, gpio, state);
 265}
 266
 267static const struct of_device_id xlp_gpio_of_ids[] = {
 268        {
 269                .compatible = "netlogic,xlp832-gpio",
 270                .data       = (void *)XLP_GPIO_VARIANT_XLP832,
 271        },
 272        {
 273                .compatible = "netlogic,xlp316-gpio",
 274                .data       = (void *)XLP_GPIO_VARIANT_XLP316,
 275        },
 276        {
 277                .compatible = "netlogic,xlp208-gpio",
 278                .data       = (void *)XLP_GPIO_VARIANT_XLP208,
 279        },
 280        {
 281                .compatible = "netlogic,xlp980-gpio",
 282                .data       = (void *)XLP_GPIO_VARIANT_XLP980,
 283        },
 284        {
 285                .compatible = "netlogic,xlp532-gpio",
 286                .data       = (void *)XLP_GPIO_VARIANT_XLP532,
 287        },
 288        { /* sentinel */ },
 289};
 290MODULE_DEVICE_TABLE(of, xlp_gpio_of_ids);
 291
 292static int xlp_gpio_probe(struct platform_device *pdev)
 293{
 294        struct gpio_chip *gc;
 295        struct resource *iores;
 296        struct xlp_gpio_priv *priv;
 297        const struct of_device_id *of_id;
 298        void __iomem *gpio_base;
 299        int irq_base, irq, err;
 300        int ngpio;
 301        u32 soc_type;
 302
 303        iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 304        if (!iores)
 305                return -ENODEV;
 306
 307        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 308        if (!priv)
 309                return -ENOMEM;
 310
 311        gpio_base = devm_ioremap_resource(&pdev->dev, iores);
 312        if (IS_ERR(gpio_base))
 313                return PTR_ERR(gpio_base);
 314
 315        irq = platform_get_irq(pdev, 0);
 316        if (irq < 0)
 317                return irq;
 318
 319        of_id = of_match_device(xlp_gpio_of_ids, &pdev->dev);
 320        if (!of_id) {
 321                dev_err(&pdev->dev, "Failed to get soc type!\n");
 322                return -ENODEV;
 323        }
 324
 325        soc_type = (uintptr_t) of_id->data;
 326
 327        switch (soc_type) {
 328        case XLP_GPIO_VARIANT_XLP832:
 329                priv->gpio_out_en = gpio_base + GPIO_OUTPUT_EN;
 330                priv->gpio_paddrv = gpio_base + GPIO_PADDRV;
 331                priv->gpio_intr_stat = gpio_base + GPIO_INT_STAT;
 332                priv->gpio_intr_type = gpio_base + GPIO_INT_TYPE;
 333                priv->gpio_intr_pol = gpio_base + GPIO_INT_POL;
 334                priv->gpio_intr_en = gpio_base + GPIO_INT_EN00;
 335                ngpio = 41;
 336                break;
 337        case XLP_GPIO_VARIANT_XLP208:
 338        case XLP_GPIO_VARIANT_XLP316:
 339                priv->gpio_out_en = gpio_base + GPIO_OUTPUT_EN;
 340                priv->gpio_paddrv = gpio_base + GPIO_PADDRV;
 341                priv->gpio_intr_stat = gpio_base + GPIO_3XX_INT_STAT;
 342                priv->gpio_intr_type = gpio_base + GPIO_3XX_INT_TYPE;
 343                priv->gpio_intr_pol = gpio_base + GPIO_3XX_INT_POL;
 344                priv->gpio_intr_en = gpio_base + GPIO_3XX_INT_EN00;
 345
 346                ngpio = (soc_type == XLP_GPIO_VARIANT_XLP208) ? 42 : 57;
 347                break;
 348        case XLP_GPIO_VARIANT_XLP980:
 349        case XLP_GPIO_VARIANT_XLP532:
 350                priv->gpio_out_en = gpio_base + GPIO_9XX_OUTPUT_EN;
 351                priv->gpio_paddrv = gpio_base + GPIO_9XX_PADDRV;
 352                priv->gpio_intr_stat = gpio_base + GPIO_9XX_INT_STAT;
 353                priv->gpio_intr_type = gpio_base + GPIO_9XX_INT_TYPE;
 354                priv->gpio_intr_pol = gpio_base + GPIO_9XX_INT_POL;
 355                priv->gpio_intr_en = gpio_base + GPIO_9XX_INT_EN00;
 356
 357                ngpio = (soc_type == XLP_GPIO_VARIANT_XLP980) ? 66 : 67;
 358                break;
 359        default:
 360                dev_err(&pdev->dev, "Unknown Processor type!\n");
 361                return -ENODEV;
 362        }
 363
 364        bitmap_zero(priv->gpio_enabled_mask, XLP_MAX_NR_GPIO);
 365
 366        gc = &priv->chip;
 367
 368        gc->owner = THIS_MODULE;
 369        gc->label = dev_name(&pdev->dev);
 370        gc->base = 0;
 371        gc->parent = &pdev->dev;
 372        gc->ngpio = ngpio;
 373        gc->of_node = pdev->dev.of_node;
 374        gc->direction_output = xlp_gpio_dir_output;
 375        gc->direction_input = xlp_gpio_dir_input;
 376        gc->set = xlp_gpio_set;
 377        gc->get = xlp_gpio_get;
 378
 379        spin_lock_init(&priv->lock);
 380        irq_base = irq_alloc_descs(-1, XLP_GPIO_IRQ_BASE, gc->ngpio, 0);
 381        if (irq_base < 0) {
 382                dev_err(&pdev->dev, "Failed to allocate IRQ numbers\n");
 383                return -ENODEV;
 384        }
 385
 386        err = gpiochip_add_data(gc, priv);
 387        if (err < 0)
 388                goto out_free_desc;
 389
 390        err = gpiochip_irqchip_add(gc, &xlp_gpio_irq_chip, irq_base,
 391                                handle_level_irq, IRQ_TYPE_NONE);
 392        if (err) {
 393                dev_err(&pdev->dev, "Could not connect irqchip to gpiochip!\n");
 394                goto out_gpio_remove;
 395        }
 396
 397        gpiochip_set_chained_irqchip(gc, &xlp_gpio_irq_chip, irq,
 398                        xlp_gpio_generic_handler);
 399
 400        dev_info(&pdev->dev, "registered %d GPIOs\n", gc->ngpio);
 401
 402        return 0;
 403
 404out_gpio_remove:
 405        gpiochip_remove(gc);
 406out_free_desc:
 407        irq_free_descs(irq_base, gc->ngpio);
 408        return err;
 409}
 410
 411static struct platform_driver xlp_gpio_driver = {
 412        .driver         = {
 413                .name   = "xlp-gpio",
 414                .of_match_table = xlp_gpio_of_ids,
 415        },
 416        .probe          = xlp_gpio_probe,
 417};
 418module_platform_driver(xlp_gpio_driver);
 419
 420MODULE_AUTHOR("Kamlakant Patel <kamlakant.patel@broadcom.com>");
 421MODULE_AUTHOR("Ganesan Ramalingam <ganesanr@broadcom.com>");
 422MODULE_DESCRIPTION("Netlogic XLP GPIO Driver");
 423MODULE_LICENSE("GPL v2");
 424