drivers/irqchip/irq-renesas-irqc.c

   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
  42 struct irqc_irq {
  43         int hw_irq;
  44         int requested_irq;
  45         int domain_irq;
  46         struct irqc_priv *p;
  47 };
  48
  49 struct 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
  60 static 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
  66 static 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
  75 static 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 static unsigned char irqc_sense[IRQ_TYPE_SENSE_MASK + 1] = {
  85         [IRQ_TYPE_LEVEL_LOW]    = 0x01,
  86         [IRQ_TYPE_LEVEL_HIGH]   = 0x02,
  87         [IRQ_TYPE_EDGE_FALLING] = 0x04, /* Synchronous */
  88         [IRQ_TYPE_EDGE_RISING]  = 0x08, /* Synchronous */
  89         [IRQ_TYPE_EDGE_BOTH]    = 0x0c, /* Synchronous */
  90 };
  91
  92 static int irqc_irq_set_type(struct irq_data *d, unsigned int type)
  93 {
  94         struct irqc_priv *p = irq_data_get_irq_chip_data(d);
  95         int hw_irq = irqd_to_hwirq(d);
  96         unsigned char value = irqc_sense[type & IRQ_TYPE_SENSE_MASK];
  97         unsigned long tmp;
  98
  99         irqc_dbg(&p->irq[hw_irq], "sense");
 100
 101         if (!value)
 102                 return -EINVAL;
 103
 104         tmp = ioread32(p->iomem + IRQC_CONFIG(hw_irq));
 105         tmp &= ~0x3f;
 106         tmp |= value;
 107         iowrite32(tmp, p->iomem + IRQC_CONFIG(hw_irq));
 108         return 0;
 109 }
 110
 111 static irqreturn_t irqc_irq_handler(int irq, void *dev_id)
 112 {
 113         struct irqc_irq *i = dev_id;
 114         struct irqc_priv *p = i->p;
 115         unsigned long bit = BIT(i->hw_irq);
 116
 117         irqc_dbg(i, "demux1");
 118
 119         if (ioread32(p->iomem + DETECT_STATUS) & bit) {
 120                 iowrite32(bit, p->iomem + DETECT_STATUS);
 121                 irqc_dbg(i, "demux2");
 122                 generic_handle_irq(i->domain_irq);
 123                 return IRQ_HANDLED;
 124         }
 125         return IRQ_NONE;
 126 }
 127
 128 static int irqc_irq_domain_map(struct irq_domain *h, unsigned int virq,
 129                                irq_hw_number_t hw)
 130 {
 131         struct irqc_priv *p = h->host_data;
 132
 133         p->irq[hw].domain_irq = virq;
 134         p->irq[hw].hw_irq = hw;
 135
 136         irqc_dbg(&p->irq[hw], "map");
 137         irq_set_chip_data(virq, h->host_data);
 138         irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
 139         set_irq_flags(virq, IRQF_VALID); /* kill me now */
 140         return 0;
 141 }
 142
 143 static struct irq_domain_ops irqc_irq_domain_ops = {
 144         .map    = irqc_irq_domain_map,
 145         .xlate  = irq_domain_xlate_twocell,
 146 };
 147
 148 static int irqc_probe(struct platform_device *pdev)
 149 {
 150         struct renesas_irqc_config *pdata = pdev->dev.platform_data;
 151         struct irqc_priv *p;
 152         struct resource *io;
 153         struct resource *irq;
 154         struct irq_chip *irq_chip;
 155         const char *name = dev_name(&pdev->dev);
 156         int ret;
 157         int k;
 158
 159         p = kzalloc(sizeof(*p), GFP_KERNEL);
 160         if (!p) {
 161                 dev_err(&pdev->dev, "failed to allocate driver data\n");
 162                 ret = -ENOMEM;
 163                 goto err0;
 164         }
 165
 166         /* deal with driver instance configuration */
 167         if (pdata)
 168                 memcpy(&p->config, pdata, sizeof(*pdata));
 169
 170         p->pdev = pdev;
 171         platform_set_drvdata(pdev, p);
 172
 173         /* get hold of manadatory IOMEM */
 174         io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 175         if (!io) {
 176                 dev_err(&pdev->dev, "not enough IOMEM resources\n");
 177                 ret = -EINVAL;
 178                 goto err1;
 179         }
 180
 181         /* allow any number of IRQs between 1 and IRQC_IRQ_MAX */
 182         for (k = 0; k < IRQC_IRQ_MAX; k++) {
 183                 irq = platform_get_resource(pdev, IORESOURCE_IRQ, k);
 184                 if (!irq)
 185                         break;
 186
 187                 p->irq[k].p = p;
 188                 p->irq[k].requested_irq = irq->start;
 189         }
 190
 191         p->number_of_irqs = k;
 192         if (p->number_of_irqs < 1) {
 193                 dev_err(&pdev->dev, "not enough IRQ resources\n");
 194                 ret = -EINVAL;
 195                 goto err1;
 196         }
 197
 198         /* ioremap IOMEM and setup read/write callbacks */
 199         p->iomem = ioremap_nocache(io->start, resource_size(io));
 200         if (!p->iomem) {
 201                 dev_err(&pdev->dev, "failed to remap IOMEM\n");
 202                 ret = -ENXIO;
 203                 goto err2;
 204         }
 205
 206         p->cpu_int_base = p->iomem + IRQC_INT_CPU_BASE(0); /* SYS-SPI */
 207
 208         irq_chip = &p->irq_chip;
 209         irq_chip->name = name;
 210         irq_chip->irq_mask = irqc_irq_disable;
 211         irq_chip->irq_unmask = irqc_irq_enable;
 212         irq_chip->irq_set_type = irqc_irq_set_type;
 213         irq_chip->flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND;
 214
 215         p->irq_domain = irq_domain_add_simple(pdev->dev.of_node,
 216                                               p->number_of_irqs,
 217                                               p->config.irq_base,
 218                                               &irqc_irq_domain_ops, p);
 219         if (!p->irq_domain) {
 220                 ret = -ENXIO;
 221                 dev_err(&pdev->dev, "cannot initialize irq domain\n");
 222                 goto err2;
 223         }
 224
 225         /* request interrupts one by one */
 226         for (k = 0; k < p->number_of_irqs; k++) {
 227                 if (request_irq(p->irq[k].requested_irq, irqc_irq_handler,
 228                                 0, name, &p->irq[k])) {
 229                         dev_err(&pdev->dev, "failed to request IRQ\n");
 230                         ret = -ENOENT;
 231                         goto err3;
 232                 }
 233         }
 234
 235         dev_info(&pdev->dev, "driving %d irqs\n", p->number_of_irqs);
 236
 237         /* warn in case of mismatch if irq base is specified */
 238         if (p->config.irq_base) {
 239                 if (p->config.irq_base != p->irq[0].domain_irq)
 240                         dev_warn(&pdev->dev, "irq base mismatch (%d/%d)\n",
 241                                  p->config.irq_base, p->irq[0].domain_irq);
 242         }
 243
 244         return 0;
 245 err3:
 246         while (--k >= 0)
 247                 free_irq(p->irq[k].requested_irq, &p->irq[k]);
 248
 249         irq_domain_remove(p->irq_domain);
 250 err2:
 251         iounmap(p->iomem);
 252 err1:
 253         kfree(p);
 254 err0:
 255         return ret;
 256 }
 257
 258 static int irqc_remove(struct platform_device *pdev)
 259 {
 260         struct irqc_priv *p = platform_get_drvdata(pdev);
 261         int k;
 262
 263         for (k = 0; k < p->number_of_irqs; k++)
 264                 free_irq(p->irq[k].requested_irq, &p->irq[k]);
 265
 266         irq_domain_remove(p->irq_domain);
 267         iounmap(p->iomem);
 268         kfree(p);
 269         return 0;
 270 }
 271
 272 static const struct of_device_id irqc_dt_ids[] = {
 273         { .compatible = "renesas,irqc", },
 274         {},
 275 };
 276 MODULE_DEVICE_TABLE(of, irqc_dt_ids);
 277
 278 static struct platform_driver irqc_device_driver = {
 279         .probe          = irqc_probe,
 280         .remove         = irqc_remove,
 281         .driver         = {
 282                 .name   = "renesas_irqc",
 283                 .of_match_table = irqc_dt_ids,
 284                 .owner  = THIS_MODULE,
 285         }
 286 };
 287
 288 static int __init irqc_init(void)
 289 {
 290         return platform_driver_register(&irqc_device_driver);
 291 }
 292 postcore_initcall(irqc_init);
 293
 294 static void __exit irqc_exit(void)
 295 {
 296         platform_driver_unregister(&irqc_device_driver);
 297 }
 298 module_exit(irqc_exit);
 299
 300 MODULE_AUTHOR("Magnus Damm");
 301 MODULE_DESCRIPTION("Renesas IRQC Driver");
 302 MODULE_LICENSE("GPL v2");