drivers/irqchip/irq-renesas-irqc.c

   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
  39 struct irqc_irq {
  40         int hw_irq;
  41         int requested_irq;
  42         struct irqc_priv *p;
  43 };
  44
  45 struct 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
  56 static struct irqc_priv *irq_data_to_priv(struct irq_data *data)
  57 {
  58         return data->domain->host_data;
  59 }
  60
  61 static 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
  66 static 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
  74 static 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
  93 static 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
 107 static 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_irq(irq_find_mapping(p->irq_domain, i->hw_irq));
 119                 return IRQ_HANDLED;
 120         }
 121         return IRQ_NONE;
 122 }
 123
 124 static 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
 211 err_remove_domain:
 212         irq_domain_remove(p->irq_domain);
 213 err_runtime_pm_disable:
 214         pm_runtime_put(dev);
 215         pm_runtime_disable(dev);
 216         return ret;
 217 }
 218
 219 static 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
 229 static 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
 239 static SIMPLE_DEV_PM_OPS(irqc_pm_ops, irqc_suspend, NULL);
 240
 241 static const struct of_device_id irqc_dt_ids[] = {
 242         { .compatible = "renesas,irqc", },
 243         {},
 244 };
 245 MODULE_DEVICE_TABLE(of, irqc_dt_ids);
 246
 247 static 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
 257 static int __init irqc_init(void)
 258 {
 259         return platform_driver_register(&irqc_device_driver);
 260 }
 261 postcore_initcall(irqc_init);
 262
 263 static void __exit irqc_exit(void)
 264 {
 265         platform_driver_unregister(&irqc_device_driver);
 266 }
 267 module_exit(irqc_exit);
 268
 269 MODULE_AUTHOR("Magnus Damm");
 270 MODULE_DESCRIPTION("Renesas IRQC Driver");
 271 MODULE_LICENSE("GPL v2");