drivers/irqchip/irq-mtk-sysirq.c

   1 /*
   2  * Copyright (c) 2014 MediaTek Inc.
   3  * Author: Joe.C <yingjoe.chen@mediatek.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <linux/irq.h>
  16 #include <linux/irqchip.h>
  17 #include <linux/irqdomain.h>
  18 #include <linux/of.h>
  19 #include <linux/of_irq.h>
  20 #include <linux/of_address.h>
  21 #include <linux/io.h>
  22 #include <linux/slab.h>
  23 #include <linux/spinlock.h>
  24
  25 struct mtk_sysirq_chip_data {
  26         spinlock_t lock;
  27         void __iomem *intpol_base;
  28 };
  29
  30 static int mtk_sysirq_set_type(struct irq_data *data, unsigned int type)
  31 {
  32         irq_hw_number_t hwirq = data->hwirq;
  33         struct mtk_sysirq_chip_data *chip_data = data->chip_data;
  34         u32 offset, reg_index, value;
  35         unsigned long flags;
  36         int ret;
  37
  38         offset = hwirq & 0x1f;
  39         reg_index = hwirq >> 5;
  40
  41         spin_lock_irqsave(&chip_data->lock, flags);
  42         value = readl_relaxed(chip_data->intpol_base + reg_index * 4);
  43         if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING) {
  44                 if (type == IRQ_TYPE_LEVEL_LOW)
  45                         type = IRQ_TYPE_LEVEL_HIGH;
  46                 else
  47                         type = IRQ_TYPE_EDGE_RISING;
  48                 value |= (1 << offset);
  49         } else {
  50                 value &= ~(1 << offset);
  51         }
  52         writel(value, chip_data->intpol_base + reg_index * 4);
  53
  54         data = data->parent_data;
  55         ret = data->chip->irq_set_type(data, type);
  56         spin_unlock_irqrestore(&chip_data->lock, flags);
  57         return ret;
  58 }
  59
  60 static struct irq_chip mtk_sysirq_chip = {
  61         .name                   = "MT_SYSIRQ",
  62         .irq_mask               = irq_chip_mask_parent,
  63         .irq_unmask             = irq_chip_unmask_parent,
  64         .irq_eoi                = irq_chip_eoi_parent,
  65         .irq_set_type           = mtk_sysirq_set_type,
  66         .irq_retrigger          = irq_chip_retrigger_hierarchy,
  67         .irq_set_affinity       = irq_chip_set_affinity_parent,
  68 };
  69
  70 static int mtk_sysirq_domain_xlate(struct irq_domain *d,
  71                                    struct device_node *controller,
  72                                    const u32 *intspec, unsigned int intsize,
  73                                    unsigned long *out_hwirq,
  74                                    unsigned int *out_type)
  75 {
  76         if (intsize != 3)
  77                 return -EINVAL;
  78
  79         /* sysirq doesn't support PPI */
  80         if (intspec[0])
  81                 return -EINVAL;
  82
  83         *out_hwirq = intspec[1];
  84         *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
  85         return 0;
  86 }
  87
  88 static int mtk_sysirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
  89                                    unsigned int nr_irqs, void *arg)
  90 {
  91         int i;
  92         irq_hw_number_t hwirq;
  93         struct of_phandle_args *irq_data = arg;
  94         struct of_phandle_args gic_data = *irq_data;
  95
  96         if (irq_data->args_count != 3)
  97                 return -EINVAL;
  98
  99         /* sysirq doesn't support PPI */
 100         if (irq_data->args[0])
 101                 return -EINVAL;
 102
 103         hwirq = irq_data->args[1];
 104         for (i = 0; i < nr_irqs; i++)
 105                 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
 106                                               &mtk_sysirq_chip,
 107                                               domain->host_data);
 108
 109         gic_data.np = domain->parent->of_node;
 110         return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &gic_data);
 111 }
 112
 113 static const struct irq_domain_ops sysirq_domain_ops = {
 114         .xlate = mtk_sysirq_domain_xlate,
 115         .alloc = mtk_sysirq_domain_alloc,
 116         .free = irq_domain_free_irqs_common,
 117 };
 118
 119 static int __init mtk_sysirq_of_init(struct device_node *node,
 120                                      struct device_node *parent)
 121 {
 122         struct irq_domain *domain, *domain_parent;
 123         struct mtk_sysirq_chip_data *chip_data;
 124         int ret, size, intpol_num;
 125         struct resource res;
 126
 127         domain_parent = irq_find_host(parent);
 128         if (!domain_parent) {
 129                 pr_err("mtk_sysirq: interrupt-parent not found\n");
 130                 return -EINVAL;
 131         }
 132
 133         ret = of_address_to_resource(node, 0, &res);
 134         if (ret)
 135                 return ret;
 136
 137         chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
 138         if (!chip_data)
 139                 return -ENOMEM;
 140
 141         size = resource_size(&res);
 142         intpol_num = size * 8;
 143         chip_data->intpol_base = ioremap(res.start, size);
 144         if (!chip_data->intpol_base) {
 145                 pr_err("mtk_sysirq: unable to map sysirq register\n");
 146                 ret = -ENXIO;
 147                 goto out_free;
 148         }
 149
 150         domain = irq_domain_add_hierarchy(domain_parent, 0, intpol_num, node,
 151                                           &sysirq_domain_ops, chip_data);
 152         if (!domain) {
 153                 ret = -ENOMEM;
 154                 goto out_unmap;
 155         }
 156         spin_lock_init(&chip_data->lock);
 157
 158         return 0;
 159
 160 out_unmap:
 161         iounmap(chip_data->intpol_base);
 162 out_free:
 163         kfree(chip_data);
 164         return ret;
 165 }
 166 IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);