linux/drivers/irqchip/irq-renesas-irqc.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Renesas IRQC Driver
   4 *
   5 *  Copyright (C) 2013 Magnus Damm
   6 */
   7
   8#include <linux/init.h>
   9#include <linux/platform_device.h>
  10#include <linux/interrupt.h>
  11#include <linux/ioport.h>
  12#include <linux/io.h>
  13#include <linux/irq.h>
  14#include <linux/irqdomain.h>
  15#include <linux/err.h>
  16#include <linux/slab.h>
  17#include <linux/module.h>
  18#include <linux/pm_runtime.h>
  19
  20#define IRQC_IRQ_MAX    32      /* maximum 32 interrupts per driver instance */
  21
  22#define IRQC_REQ_STS    0x00    /* Interrupt Request Status Register */
  23#define IRQC_EN_STS     0x04    /* Interrupt Enable Status Register */
  24#define IRQC_EN_SET     0x08    /* Interrupt Enable Set Register */
  25#define IRQC_INT_CPU_BASE(n) (0x000 + ((n) * 0x10))
  26                                /* SYS-CPU vs. RT-CPU */
  27#define DETECT_STATUS   0x100   /* IRQn Detect Status Register */
  28#define MONITOR         0x104   /* IRQn Signal Level Monitor Register */
  29#define HLVL_STS        0x108   /* IRQn High Level Detect Status Register */
  30#define LLVL_STS        0x10c   /* IRQn Low Level Detect Status Register */
  31#define S_R_EDGE_STS    0x110   /* IRQn Sync Rising Edge Detect Status Reg. */
  32#define S_F_EDGE_STS    0x114   /* IRQn Sync Falling Edge Detect Status Reg. */
  33#define A_R_EDGE_STS    0x118   /* IRQn Async Rising Edge Detect Status Reg. */
  34#define A_F_EDGE_STS    0x11c   /* IRQn Async Falling Edge Detect Status Reg. */
  35#define CHTEN_STS       0x120   /* Chattering Reduction Status Register */
  36#define IRQC_CONFIG(n) (0x180 + ((n) * 0x04))
  37                                /* IRQn Configuration Register */
  38
  39struct irqc_irq {
  40        int hw_irq;
  41        int requested_irq;
  42        struct irqc_priv *p;
  43};
  44
  45struct irqc_priv {
  46        void __iomem *iomem;
  47        void __iomem *cpu_int_base;
  48        struct irqc_irq irq[IRQC_IRQ_MAX];
  49        unsigned int number_of_irqs;
  50        struct device *dev;
  51        struct irq_chip_generic *gc;
  52        struct irq_domain *irq_domain;
  53        atomic_t wakeup_path;
  54};
  55
  56static struct irqc_priv *irq_data_to_priv(struct irq_data *data)
  57{
  58        return data->domain->host_data;
  59}
  60
  61static void irqc_dbg(struct irqc_irq *i, char *str)
  62{
  63        dev_dbg(i->p->dev, "%s (%d:%d)\n", str, i->requested_irq, i->hw_irq);
  64}
  65
  66static unsigned char irqc_sense[IRQ_TYPE_SENSE_MASK + 1] = {
  67        [IRQ_TYPE_LEVEL_LOW]    = 0x01,
  68        [IRQ_TYPE_LEVEL_HIGH]   = 0x02,
  69        [IRQ_TYPE_EDGE_FALLING] = 0x04, /* Synchronous */
  70        [IRQ_TYPE_EDGE_RISING]  = 0x08, /* Synchronous */
  71        [IRQ_TYPE_EDGE_BOTH]    = 0x0c, /* Synchronous */
  72};
  73
  74static int irqc_irq_set_type(struct irq_data *d, unsigned int type)
  75{
  76        struct irqc_priv *p = irq_data_to_priv(d);
  77        int hw_irq = irqd_to_hwirq(d);
  78        unsigned char value = irqc_sense[type & IRQ_TYPE_SENSE_MASK];
  79        u32 tmp;
  80
  81        irqc_dbg(&p->irq[hw_irq], "sense");
  82
  83        if (!value)
  84                return -EINVAL;
  85
  86        tmp = ioread32(p->iomem + IRQC_CONFIG(hw_irq));
  87        tmp &= ~0x3f;
  88        tmp |= value;
  89        iowrite32(tmp, p->iomem + IRQC_CONFIG(hw_irq));
  90        return 0;
  91}
  92
  93static int irqc_irq_set_wake(struct irq_data *d, unsigned int on)
  94{
  95        struct irqc_priv *p = irq_data_to_priv(d);
  96        int hw_irq = irqd_to_hwirq(d);
  97
  98        irq_set_irq_wake(p->irq[hw_irq].requested_irq, on);
  99        if (on)
 100                atomic_inc(&p->wakeup_path);
 101        else
 102                atomic_dec(&p->wakeup_path);
 103
 104        return 0;
 105}
 106
 107static irqreturn_t irqc_irq_handler(int irq, void *dev_id)
 108{
 109        struct irqc_irq *i = dev_id;
 110        struct irqc_priv *p = i->p;
 111        u32 bit = BIT(i->hw_irq);
 112
 113        irqc_dbg(i, "demux1");
 114
 115        if (ioread32(p->iomem + DETECT_STATUS) & bit) {
 116                iowrite32(bit, p->iomem + DETECT_STATUS);
 117                irqc_dbg(i, "demux2");
 118                generic_handle_domain_irq(p->irq_domain, i->hw_irq);
 119                return IRQ_HANDLED;
 120        }
 121        return IRQ_NONE;
 122}
 123
 124static int irqc_probe(struct platform_device *pdev)
 125{
 126        struct device *dev = &pdev->dev;
 127        const char *name = dev_name(dev);
 128        struct irqc_priv *p;
 129        struct resource *irq;
 130        int ret;
 131        int k;
 132
 133        p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
 134        if (!p)
 135                return -ENOMEM;
 136
 137        p->dev = dev;
 138        platform_set_drvdata(pdev, p);
 139
 140        pm_runtime_enable(dev);
 141        pm_runtime_get_sync(dev);
 142
 143        /* allow any number of IRQs between 1 and IRQC_IRQ_MAX */
 144        for (k = 0; k < IRQC_IRQ_MAX; k++) {
 145                irq = platform_get_resource(pdev, IORESOURCE_IRQ, k);
 146                if (!irq)
 147                        break;
 148
 149                p->irq[k].p = p;
 150                p->irq[k].hw_irq = k;
 151                p->irq[k].requested_irq = irq->start;
 152        }
 153
 154        p->number_of_irqs = k;
 155        if (p->number_of_irqs < 1) {
 156                dev_err(dev, "not enough IRQ resources\n");
 157                ret = -EINVAL;
 158                goto err_runtime_pm_disable;
 159        }
 160
 161        /* ioremap IOMEM and setup read/write callbacks */
 162        p->iomem = devm_platform_ioremap_resource(pdev, 0);
 163        if (IS_ERR(p->iomem)) {
 164                ret = PTR_ERR(p->iomem);
 165                goto err_runtime_pm_disable;
 166        }
 167
 168        p->cpu_int_base = p->iomem + IRQC_INT_CPU_BASE(0); /* SYS-SPI */
 169
 170        p->irq_domain = irq_domain_add_linear(dev->of_node, p->number_of_irqs,
 171                                              &irq_generic_chip_ops, p);
 172        if (!p->irq_domain) {
 173                ret = -ENXIO;
 174                dev_err(dev, "cannot initialize irq domain\n");
 175                goto err_runtime_pm_disable;
 176        }
 177
 178        ret = irq_alloc_domain_generic_chips(p->irq_domain, p->number_of_irqs,
 179                                             1, "irqc", handle_level_irq,
 180                                             0, 0, IRQ_GC_INIT_NESTED_LOCK);
 181        if (ret) {
 182                dev_err(dev, "cannot allocate generic chip\n");
 183                goto err_remove_domain;
 184        }
 185
 186        p->gc = irq_get_domain_generic_chip(p->irq_domain, 0);
 187        p->gc->reg_base = p->cpu_int_base;
 188        p->gc->chip_types[0].regs.enable = IRQC_EN_SET;
 189        p->gc->chip_types[0].regs.disable = IRQC_EN_STS;
 190        p->gc->chip_types[0].chip.parent_device = dev;
 191        p->gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
 192        p->gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
 193        p->gc->chip_types[0].chip.irq_set_type  = irqc_irq_set_type;
 194        p->gc->chip_types[0].chip.irq_set_wake  = irqc_irq_set_wake;
 195        p->gc->chip_types[0].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
 196
 197        /* request interrupts one by one */
 198        for (k = 0; k < p->number_of_irqs; k++) {
 199                if (devm_request_irq(dev, p->irq[k].requested_irq,
 200                                     irqc_irq_handler, 0, name, &p->irq[k])) {
 201                        dev_err(dev, "failed to request IRQ\n");
 202                        ret = -ENOENT;
 203                        goto err_remove_domain;
 204                }
 205        }
 206
 207        dev_info(dev, "driving %d irqs\n", p->number_of_irqs);
 208
 209        return 0;
 210
 211err_remove_domain:
 212        irq_domain_remove(p->irq_domain);
 213err_runtime_pm_disable:
 214        pm_runtime_put(dev);
 215        pm_runtime_disable(dev);
 216        return ret;
 217}
 218
 219static int irqc_remove(struct platform_device *pdev)
 220{
 221        struct irqc_priv *p = platform_get_drvdata(pdev);
 222
 223        irq_domain_remove(p->irq_domain);
 224        pm_runtime_put(&pdev->dev);
 225        pm_runtime_disable(&pdev->dev);
 226        return 0;
 227}
 228
 229static int __maybe_unused irqc_suspend(struct device *dev)
 230{
 231        struct irqc_priv *p = dev_get_drvdata(dev);
 232
 233        if (atomic_read(&p->wakeup_path))
 234                device_set_wakeup_path(dev);
 235
 236        return 0;
 237}
 238
 239static SIMPLE_DEV_PM_OPS(irqc_pm_ops, irqc_suspend, NULL);
 240
 241static const struct of_device_id irqc_dt_ids[] = {
 242        { .compatible = "renesas,irqc", },
 243        {},
 244};
 245MODULE_DEVICE_TABLE(of, irqc_dt_ids);
 246
 247static struct platform_driver irqc_device_driver = {
 248        .probe          = irqc_probe,
 249        .remove         = irqc_remove,
 250        .driver         = {
 251                .name   = "renesas_irqc",
 252                .of_match_table = irqc_dt_ids,
 253                .pm     = &irqc_pm_ops,
 254        }
 255};
 256
 257static int __init irqc_init(void)
 258{
 259        return platform_driver_register(&irqc_device_driver);
 260}
 261postcore_initcall(irqc_init);
 262
 263static void __exit irqc_exit(void)
 264{
 265        platform_driver_unregister(&irqc_device_driver);
 266}
 267module_exit(irqc_exit);
 268
 269MODULE_AUTHOR("Magnus Damm");
 270MODULE_DESCRIPTION("Renesas IRQC Driver");
 271MODULE_LICENSE("GPL v2");
 272