linux/drivers/gpio/gpio-mxs.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2//
   3// MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
   4// Copyright 2008 Juergen Beisert, kernel@pengutronix.de
   5//
   6// Based on code from Freescale,
   7// Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
   8
   9#include <linux/err.h>
  10#include <linux/init.h>
  11#include <linux/interrupt.h>
  12#include <linux/io.h>
  13#include <linux/irq.h>
  14#include <linux/irqdomain.h>
  15#include <linux/of.h>
  16#include <linux/of_address.h>
  17#include <linux/of_device.h>
  18#include <linux/platform_device.h>
  19#include <linux/slab.h>
  20#include <linux/gpio/driver.h>
  21#include <linux/module.h>
  22
  23#define MXS_SET         0x4
  24#define MXS_CLR         0x8
  25
  26#define PINCTRL_DOUT(p)         ((is_imx23_gpio(p) ? 0x0500 : 0x0700) + (p->id) * 0x10)
  27#define PINCTRL_DIN(p)          ((is_imx23_gpio(p) ? 0x0600 : 0x0900) + (p->id) * 0x10)
  28#define PINCTRL_DOE(p)          ((is_imx23_gpio(p) ? 0x0700 : 0x0b00) + (p->id) * 0x10)
  29#define PINCTRL_PIN2IRQ(p)      ((is_imx23_gpio(p) ? 0x0800 : 0x1000) + (p->id) * 0x10)
  30#define PINCTRL_IRQEN(p)        ((is_imx23_gpio(p) ? 0x0900 : 0x1100) + (p->id) * 0x10)
  31#define PINCTRL_IRQLEV(p)       ((is_imx23_gpio(p) ? 0x0a00 : 0x1200) + (p->id) * 0x10)
  32#define PINCTRL_IRQPOL(p)       ((is_imx23_gpio(p) ? 0x0b00 : 0x1300) + (p->id) * 0x10)
  33#define PINCTRL_IRQSTAT(p)      ((is_imx23_gpio(p) ? 0x0c00 : 0x1400) + (p->id) * 0x10)
  34
  35#define GPIO_INT_FALL_EDGE      0x0
  36#define GPIO_INT_LOW_LEV        0x1
  37#define GPIO_INT_RISE_EDGE      0x2
  38#define GPIO_INT_HIGH_LEV       0x3
  39#define GPIO_INT_LEV_MASK       (1 << 0)
  40#define GPIO_INT_POL_MASK       (1 << 1)
  41
  42enum mxs_gpio_id {
  43        IMX23_GPIO,
  44        IMX28_GPIO,
  45};
  46
  47struct mxs_gpio_port {
  48        void __iomem *base;
  49        int id;
  50        int irq;
  51        struct irq_domain *domain;
  52        struct gpio_chip gc;
  53        struct device *dev;
  54        enum mxs_gpio_id devid;
  55        u32 both_edges;
  56};
  57
  58static inline int is_imx23_gpio(struct mxs_gpio_port *port)
  59{
  60        return port->devid == IMX23_GPIO;
  61}
  62
  63/* Note: This driver assumes 32 GPIOs are handled in one register */
  64
  65static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
  66{
  67        u32 val;
  68        u32 pin_mask = 1 << d->hwirq;
  69        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  70        struct irq_chip_type *ct = irq_data_get_chip_type(d);
  71        struct mxs_gpio_port *port = gc->private;
  72        void __iomem *pin_addr;
  73        int edge;
  74
  75        if (!(ct->type & type))
  76                if (irq_setup_alt_chip(d, type))
  77                        return -EINVAL;
  78
  79        port->both_edges &= ~pin_mask;
  80        switch (type) {
  81        case IRQ_TYPE_EDGE_BOTH:
  82                val = readl(port->base + PINCTRL_DIN(port)) & pin_mask;
  83                if (val)
  84                        edge = GPIO_INT_FALL_EDGE;
  85                else
  86                        edge = GPIO_INT_RISE_EDGE;
  87                port->both_edges |= pin_mask;
  88                break;
  89        case IRQ_TYPE_EDGE_RISING:
  90                edge = GPIO_INT_RISE_EDGE;
  91                break;
  92        case IRQ_TYPE_EDGE_FALLING:
  93                edge = GPIO_INT_FALL_EDGE;
  94                break;
  95        case IRQ_TYPE_LEVEL_LOW:
  96                edge = GPIO_INT_LOW_LEV;
  97                break;
  98        case IRQ_TYPE_LEVEL_HIGH:
  99                edge = GPIO_INT_HIGH_LEV;
 100                break;
 101        default:
 102                return -EINVAL;
 103        }
 104
 105        /* set level or edge */
 106        pin_addr = port->base + PINCTRL_IRQLEV(port);
 107        if (edge & GPIO_INT_LEV_MASK) {
 108                writel(pin_mask, pin_addr + MXS_SET);
 109                writel(pin_mask, port->base + PINCTRL_IRQEN(port) + MXS_SET);
 110        } else {
 111                writel(pin_mask, pin_addr + MXS_CLR);
 112                writel(pin_mask, port->base + PINCTRL_PIN2IRQ(port) + MXS_SET);
 113        }
 114
 115        /* set polarity */
 116        pin_addr = port->base + PINCTRL_IRQPOL(port);
 117        if (edge & GPIO_INT_POL_MASK)
 118                writel(pin_mask, pin_addr + MXS_SET);
 119        else
 120                writel(pin_mask, pin_addr + MXS_CLR);
 121
 122        writel(pin_mask, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
 123
 124        return 0;
 125}
 126
 127static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio)
 128{
 129        u32 bit, val, edge;
 130        void __iomem *pin_addr;
 131
 132        bit = 1 << gpio;
 133
 134        pin_addr = port->base + PINCTRL_IRQPOL(port);
 135        val = readl(pin_addr);
 136        edge = val & bit;
 137
 138        if (edge)
 139                writel(bit, pin_addr + MXS_CLR);
 140        else
 141                writel(bit, pin_addr + MXS_SET);
 142}
 143
 144/* MXS has one interrupt *per* gpio port */
 145static void mxs_gpio_irq_handler(struct irq_desc *desc)
 146{
 147        u32 irq_stat;
 148        struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);
 149
 150        desc->irq_data.chip->irq_ack(&desc->irq_data);
 151
 152        irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
 153                        readl(port->base + PINCTRL_IRQEN(port));
 154
 155        while (irq_stat != 0) {
 156                int irqoffset = fls(irq_stat) - 1;
 157                if (port->both_edges & (1 << irqoffset))
 158                        mxs_flip_edge(port, irqoffset);
 159
 160                generic_handle_domain_irq(port->domain, irqoffset);
 161                irq_stat &= ~(1 << irqoffset);
 162        }
 163}
 164
 165/*
 166 * Set interrupt number "irq" in the GPIO as a wake-up source.
 167 * While system is running, all registered GPIO interrupts need to have
 168 * wake-up enabled. When system is suspended, only selected GPIO interrupts
 169 * need to have wake-up enabled.
 170 * @param  irq          interrupt source number
 171 * @param  enable       enable as wake-up if equal to non-zero
 172 * @return       This function returns 0 on success.
 173 */
 174static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable)
 175{
 176        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 177        struct mxs_gpio_port *port = gc->private;
 178
 179        if (enable)
 180                enable_irq_wake(port->irq);
 181        else
 182                disable_irq_wake(port->irq);
 183
 184        return 0;
 185}
 186
 187static int mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
 188{
 189        struct irq_chip_generic *gc;
 190        struct irq_chip_type *ct;
 191        int rv;
 192
 193        gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxs", 2, irq_base,
 194                                         port->base, handle_level_irq);
 195        if (!gc)
 196                return -ENOMEM;
 197
 198        gc->private = port;
 199
 200        ct = &gc->chip_types[0];
 201        ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
 202        ct->chip.irq_ack = irq_gc_ack_set_bit;
 203        ct->chip.irq_mask = irq_gc_mask_disable_reg;
 204        ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
 205        ct->chip.irq_set_type = mxs_gpio_set_irq_type;
 206        ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
 207        ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
 208        ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
 209        ct->regs.enable = PINCTRL_PIN2IRQ(port) + MXS_SET;
 210        ct->regs.disable = PINCTRL_PIN2IRQ(port) + MXS_CLR;
 211
 212        ct = &gc->chip_types[1];
 213        ct->type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING;
 214        ct->chip.irq_ack = irq_gc_ack_set_bit;
 215        ct->chip.irq_mask = irq_gc_mask_disable_reg;
 216        ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
 217        ct->chip.irq_set_type = mxs_gpio_set_irq_type;
 218        ct->chip.irq_set_wake = mxs_gpio_set_wake_irq;
 219        ct->chip.flags = IRQCHIP_SET_TYPE_MASKED;
 220        ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR;
 221        ct->regs.enable = PINCTRL_IRQEN(port) + MXS_SET;
 222        ct->regs.disable = PINCTRL_IRQEN(port) + MXS_CLR;
 223        ct->handler = handle_level_irq;
 224
 225        rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32),
 226                                         IRQ_GC_INIT_NESTED_LOCK,
 227                                         IRQ_NOREQUEST, 0);
 228
 229        return rv;
 230}
 231
 232static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
 233{
 234        struct mxs_gpio_port *port = gpiochip_get_data(gc);
 235
 236        return irq_find_mapping(port->domain, offset);
 237}
 238
 239static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
 240{
 241        struct mxs_gpio_port *port = gpiochip_get_data(gc);
 242        u32 mask = 1 << offset;
 243        u32 dir;
 244
 245        dir = readl(port->base + PINCTRL_DOE(port));
 246        if (dir & mask)
 247                return GPIO_LINE_DIRECTION_OUT;
 248
 249        return GPIO_LINE_DIRECTION_IN;
 250}
 251
 252static const struct of_device_id mxs_gpio_dt_ids[] = {
 253        { .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, },
 254        { .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, },
 255        { /* sentinel */ }
 256};
 257MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids);
 258
 259static int mxs_gpio_probe(struct platform_device *pdev)
 260{
 261        struct device_node *np = pdev->dev.of_node;
 262        struct device_node *parent;
 263        static void __iomem *base;
 264        struct mxs_gpio_port *port;
 265        int irq_base;
 266        int err;
 267
 268        port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
 269        if (!port)
 270                return -ENOMEM;
 271
 272        port->id = of_alias_get_id(np, "gpio");
 273        if (port->id < 0)
 274                return port->id;
 275        port->devid = (enum mxs_gpio_id)of_device_get_match_data(&pdev->dev);
 276        port->dev = &pdev->dev;
 277        port->irq = platform_get_irq(pdev, 0);
 278        if (port->irq < 0)
 279                return port->irq;
 280
 281        /*
 282         * map memory region only once, as all the gpio ports
 283         * share the same one
 284         */
 285        if (!base) {
 286                parent = of_get_parent(np);
 287                base = of_iomap(parent, 0);
 288                of_node_put(parent);
 289                if (!base)
 290                        return -EADDRNOTAVAIL;
 291        }
 292        port->base = base;
 293
 294        /* initially disable the interrupts */
 295        writel(0, port->base + PINCTRL_PIN2IRQ(port));
 296        writel(0, port->base + PINCTRL_IRQEN(port));
 297
 298        /* clear address has to be used to clear IRQSTAT bits */
 299        writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
 300
 301        irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id());
 302        if (irq_base < 0) {
 303                err = irq_base;
 304                goto out_iounmap;
 305        }
 306
 307        port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
 308                                             &irq_domain_simple_ops, NULL);
 309        if (!port->domain) {
 310                err = -ENODEV;
 311                goto out_iounmap;
 312        }
 313
 314        /* gpio-mxs can be a generic irq chip */
 315        err = mxs_gpio_init_gc(port, irq_base);
 316        if (err < 0)
 317                goto out_irqdomain_remove;
 318
 319        /* setup one handler for each entry */
 320        irq_set_chained_handler_and_data(port->irq, mxs_gpio_irq_handler,
 321                                         port);
 322
 323        err = bgpio_init(&port->gc, &pdev->dev, 4,
 324                         port->base + PINCTRL_DIN(port),
 325                         port->base + PINCTRL_DOUT(port) + MXS_SET,
 326                         port->base + PINCTRL_DOUT(port) + MXS_CLR,
 327                         port->base + PINCTRL_DOE(port), NULL, 0);
 328        if (err)
 329                goto out_irqdomain_remove;
 330
 331        port->gc.to_irq = mxs_gpio_to_irq;
 332        port->gc.get_direction = mxs_gpio_get_direction;
 333        port->gc.base = port->id * 32;
 334
 335        err = gpiochip_add_data(&port->gc, port);
 336        if (err)
 337                goto out_irqdomain_remove;
 338
 339        return 0;
 340
 341out_irqdomain_remove:
 342        irq_domain_remove(port->domain);
 343out_iounmap:
 344        iounmap(port->base);
 345        return err;
 346}
 347
 348static struct platform_driver mxs_gpio_driver = {
 349        .driver         = {
 350                .name   = "gpio-mxs",
 351                .of_match_table = mxs_gpio_dt_ids,
 352                .suppress_bind_attrs = true,
 353        },
 354        .probe          = mxs_gpio_probe,
 355};
 356
 357static int __init mxs_gpio_init(void)
 358{
 359        return platform_driver_register(&mxs_gpio_driver);
 360}
 361postcore_initcall(mxs_gpio_init);
 362
 363MODULE_AUTHOR("Freescale Semiconductor, "
 364              "Daniel Mack <danielncaiaq.de>, "
 365              "Juergen Beisert <kernel@pengutronix.de>");
 366MODULE_DESCRIPTION("Freescale MXS GPIO");
 367MODULE_LICENSE("GPL");
 368