linux/drivers/irqchip/irq-renesas-irqc.c
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   1/*
   2 * Renesas IRQC Driver
   3 *
   4 *  Copyright (C) 2013 Magnus Damm
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write to the Free Software
  17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 */
  19
  20#include <linux/init.h>
  21#include <linux/platform_device.h>
  22#include <linux/spinlock.h>
  23#include <linux/interrupt.h>
  24#include <linux/ioport.h>
  25#include <linux/io.h>
  26#include <linux/irq.h>
  27#include <linux/irqdomain.h>
  28#include <linux/err.h>
  29#include <linux/slab.h>
  30#include <linux/module.h>
  31#include <linux/platform_data/irq-renesas-irqc.h>
  32
  33#define IRQC_IRQ_MAX 32 /* maximum 32 interrupts per driver instance */
  34
  35#define IRQC_REQ_STS 0x00
  36#define IRQC_EN_STS 0x04
  37#define IRQC_EN_SET 0x08
  38#define IRQC_INT_CPU_BASE(n) (0x000 + ((n) * 0x10))
  39#define DETECT_STATUS 0x100
  40#define IRQC_CONFIG(n) (0x180 + ((n) * 0x04))
  41
  42struct irqc_irq {
  43        int hw_irq;
  44        int requested_irq;
  45        int domain_irq;
  46        struct irqc_priv *p;
  47};
  48
  49struct irqc_priv {
  50        void __iomem *iomem;
  51        void __iomem *cpu_int_base;
  52        struct irqc_irq irq[IRQC_IRQ_MAX];
  53        struct renesas_irqc_config config;
  54        unsigned int number_of_irqs;
  55        struct platform_device *pdev;
  56        struct irq_chip irq_chip;
  57        struct irq_domain *irq_domain;
  58};
  59
  60static void irqc_dbg(struct irqc_irq *i, char *str)
  61{
  62        dev_dbg(&i->p->pdev->dev, "%s (%d:%d:%d)\n",
  63                str, i->requested_irq, i->hw_irq, i->domain_irq);
  64}
  65
  66static void irqc_irq_enable(struct irq_data *d)
  67{
  68        struct irqc_priv *p = irq_data_get_irq_chip_data(d);
  69        int hw_irq = irqd_to_hwirq(d);
  70
  71        irqc_dbg(&p->irq[hw_irq], "enable");
  72        iowrite32(BIT(hw_irq), p->cpu_int_base + IRQC_EN_SET);
  73}
  74
  75static void irqc_irq_disable(struct irq_data *d)
  76{
  77        struct irqc_priv *p = irq_data_get_irq_chip_data(d);
  78        int hw_irq = irqd_to_hwirq(d);
  79
  80        irqc_dbg(&p->irq[hw_irq], "disable");
  81        iowrite32(BIT(hw_irq), p->cpu_int_base + IRQC_EN_STS);
  82}
  83
  84#define INTC_IRQ_SENSE_VALID 0x10
  85#define INTC_IRQ_SENSE(x) (x + INTC_IRQ_SENSE_VALID)
  86
  87static unsigned char irqc_sense[IRQ_TYPE_SENSE_MASK + 1] = {
  88        [IRQ_TYPE_LEVEL_LOW] = INTC_IRQ_SENSE(0x01),
  89        [IRQ_TYPE_LEVEL_HIGH] = INTC_IRQ_SENSE(0x02),
  90        [IRQ_TYPE_EDGE_FALLING] = INTC_IRQ_SENSE(0x04), /* Synchronous */
  91        [IRQ_TYPE_EDGE_RISING] = INTC_IRQ_SENSE(0x08), /* Synchronous */
  92        [IRQ_TYPE_EDGE_BOTH] = INTC_IRQ_SENSE(0x0c),  /* Synchronous */
  93};
  94
  95static int irqc_irq_set_type(struct irq_data *d, unsigned int type)
  96{
  97        struct irqc_priv *p = irq_data_get_irq_chip_data(d);
  98        int hw_irq = irqd_to_hwirq(d);
  99        unsigned char value = irqc_sense[type & IRQ_TYPE_SENSE_MASK];
 100        unsigned long tmp;
 101
 102        irqc_dbg(&p->irq[hw_irq], "sense");
 103
 104        if (!(value & INTC_IRQ_SENSE_VALID))
 105                return -EINVAL;
 106
 107        tmp = ioread32(p->iomem + IRQC_CONFIG(hw_irq));
 108        tmp &= ~0x3f;
 109        tmp |= value ^ INTC_IRQ_SENSE_VALID;
 110        iowrite32(tmp, p->iomem + IRQC_CONFIG(hw_irq));
 111        return 0;
 112}
 113
 114static irqreturn_t irqc_irq_handler(int irq, void *dev_id)
 115{
 116        struct irqc_irq *i = dev_id;
 117        struct irqc_priv *p = i->p;
 118        unsigned long bit = BIT(i->hw_irq);
 119
 120        irqc_dbg(i, "demux1");
 121
 122        if (ioread32(p->iomem + DETECT_STATUS) & bit) {
 123                iowrite32(bit, p->iomem + DETECT_STATUS);
 124                irqc_dbg(i, "demux2");
 125                generic_handle_irq(i->domain_irq);
 126                return IRQ_HANDLED;
 127        }
 128        return IRQ_NONE;
 129}
 130
 131static int irqc_irq_domain_map(struct irq_domain *h, unsigned int virq,
 132                               irq_hw_number_t hw)
 133{
 134        struct irqc_priv *p = h->host_data;
 135
 136        p->irq[hw].domain_irq = virq;
 137        p->irq[hw].hw_irq = hw;
 138
 139        irqc_dbg(&p->irq[hw], "map");
 140        irq_set_chip_data(virq, h->host_data);
 141        irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
 142        set_irq_flags(virq, IRQF_VALID); /* kill me now */
 143        return 0;
 144}
 145
 146static struct irq_domain_ops irqc_irq_domain_ops = {
 147        .map    = irqc_irq_domain_map,
 148        .xlate  = irq_domain_xlate_twocell,
 149};
 150
 151static int irqc_probe(struct platform_device *pdev)
 152{
 153        struct renesas_irqc_config *pdata = pdev->dev.platform_data;
 154        struct irqc_priv *p;
 155        struct resource *io;
 156        struct resource *irq;
 157        struct irq_chip *irq_chip;
 158        const char *name = dev_name(&pdev->dev);
 159        int ret;
 160        int k;
 161
 162        p = kzalloc(sizeof(*p), GFP_KERNEL);
 163        if (!p) {
 164                dev_err(&pdev->dev, "failed to allocate driver data\n");
 165                ret = -ENOMEM;
 166                goto err0;
 167        }
 168
 169        /* deal with driver instance configuration */
 170        if (pdata)
 171                memcpy(&p->config, pdata, sizeof(*pdata));
 172
 173        p->pdev = pdev;
 174        platform_set_drvdata(pdev, p);
 175
 176        /* get hold of manadatory IOMEM */
 177        io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 178        if (!io) {
 179                dev_err(&pdev->dev, "not enough IOMEM resources\n");
 180                ret = -EINVAL;
 181                goto err1;
 182        }
 183
 184        /* allow any number of IRQs between 1 and IRQC_IRQ_MAX */
 185        for (k = 0; k < IRQC_IRQ_MAX; k++) {
 186                irq = platform_get_resource(pdev, IORESOURCE_IRQ, k);
 187                if (!irq)
 188                        break;
 189
 190                p->irq[k].p = p;
 191                p->irq[k].requested_irq = irq->start;
 192        }
 193
 194        p->number_of_irqs = k;
 195        if (p->number_of_irqs < 1) {
 196                dev_err(&pdev->dev, "not enough IRQ resources\n");
 197                ret = -EINVAL;
 198                goto err1;
 199        }
 200
 201        /* ioremap IOMEM and setup read/write callbacks */
 202        p->iomem = ioremap_nocache(io->start, resource_size(io));
 203        if (!p->iomem) {
 204                dev_err(&pdev->dev, "failed to remap IOMEM\n");
 205                ret = -ENXIO;
 206                goto err2;
 207        }
 208
 209        p->cpu_int_base = p->iomem + IRQC_INT_CPU_BASE(0); /* SYS-SPI */
 210
 211        irq_chip = &p->irq_chip;
 212        irq_chip->name = name;
 213        irq_chip->irq_mask = irqc_irq_disable;
 214        irq_chip->irq_unmask = irqc_irq_enable;
 215        irq_chip->irq_enable = irqc_irq_enable;
 216        irq_chip->irq_disable = irqc_irq_disable;
 217        irq_chip->irq_set_type = irqc_irq_set_type;
 218        irq_chip->flags = IRQCHIP_SKIP_SET_WAKE;
 219
 220        p->irq_domain = irq_domain_add_simple(pdev->dev.of_node,
 221                                              p->number_of_irqs,
 222                                              p->config.irq_base,
 223                                              &irqc_irq_domain_ops, p);
 224        if (!p->irq_domain) {
 225                ret = -ENXIO;
 226                dev_err(&pdev->dev, "cannot initialize irq domain\n");
 227                goto err2;
 228        }
 229
 230        /* request interrupts one by one */
 231        for (k = 0; k < p->number_of_irqs; k++) {
 232                if (request_irq(p->irq[k].requested_irq, irqc_irq_handler,
 233                                0, name, &p->irq[k])) {
 234                        dev_err(&pdev->dev, "failed to request IRQ\n");
 235                        ret = -ENOENT;
 236                        goto err3;
 237                }
 238        }
 239
 240        dev_info(&pdev->dev, "driving %d irqs\n", p->number_of_irqs);
 241
 242        /* warn in case of mismatch if irq base is specified */
 243        if (p->config.irq_base) {
 244                if (p->config.irq_base != p->irq[0].domain_irq)
 245                        dev_warn(&pdev->dev, "irq base mismatch (%d/%d)\n",
 246                                 p->config.irq_base, p->irq[0].domain_irq);
 247        }
 248
 249        return 0;
 250err3:
 251        for (; k >= 0; k--)
 252                free_irq(p->irq[k - 1].requested_irq, &p->irq[k - 1]);
 253
 254        irq_domain_remove(p->irq_domain);
 255err2:
 256        iounmap(p->iomem);
 257err1:
 258        kfree(p);
 259err0:
 260        return ret;
 261}
 262
 263static int irqc_remove(struct platform_device *pdev)
 264{
 265        struct irqc_priv *p = platform_get_drvdata(pdev);
 266        int k;
 267
 268        for (k = 0; k < p->number_of_irqs; k++)
 269                free_irq(p->irq[k].requested_irq, &p->irq[k]);
 270
 271        irq_domain_remove(p->irq_domain);
 272        iounmap(p->iomem);
 273        kfree(p);
 274        return 0;
 275}
 276
 277static const struct of_device_id irqc_dt_ids[] = {
 278        { .compatible = "renesas,irqc", },
 279        {},
 280};
 281MODULE_DEVICE_TABLE(of, irqc_dt_ids);
 282
 283static struct platform_driver irqc_device_driver = {
 284        .probe          = irqc_probe,
 285        .remove         = irqc_remove,
 286        .driver         = {
 287                .name   = "renesas_irqc",
 288                .of_match_table = irqc_dt_ids,
 289                .owner  = THIS_MODULE,
 290        }
 291};
 292
 293static int __init irqc_init(void)
 294{
 295        return platform_driver_register(&irqc_device_driver);
 296}
 297postcore_initcall(irqc_init);
 298
 299static void __exit irqc_exit(void)
 300{
 301        platform_driver_unregister(&irqc_device_driver);
 302}
 303module_exit(irqc_exit);
 304
 305MODULE_AUTHOR("Magnus Damm");
 306MODULE_DESCRIPTION("Renesas IRQC Driver");
 307MODULE_LICENSE("GPL v2");
 308
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