/*
* Abilis Systems interrupt controller driver
*
* Copyright (C) Abilis Systems 2012
*
* Author: Christian Ruppert <christian.ruppert@abilis.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/bitops.h>
#define AB_IRQCTL_INT_ENABLE 0x00
#define AB_IRQCTL_INT_STATUS 0x04
#define AB_IRQCTL_SRC_MODE 0x08
#define AB_IRQCTL_SRC_POLARITY 0x0C
#define AB_IRQCTL_INT_MODE 0x10
#define AB_IRQCTL_INT_POLARITY 0x14
#define AB_IRQCTL_INT_FORCE 0x18
#define AB_IRQCTL_MAXIRQ 32
static inline void ab_irqctl_writereg(struct irq_chip_generic *gc, u32 reg,
u32 val)
{
irq_reg_writel(gc, val, reg);
}
static inline u32 ab_irqctl_readreg(struct irq_chip_generic *gc, u32 reg)
{
return irq_reg_readl(gc, reg);
}
static int tb10x_irq_set_type(struct irq_data *data, unsigned int flow_type)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
uint32_t im, mod, pol;
im = data->mask;
irq_gc_lock(gc);
mod = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_MODE) | im;
pol = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_POLARITY) | im;
switch (flow_type & IRQF_TRIGGER_MASK) {
case IRQ_TYPE_EDGE_FALLING:
pol ^= im;
break;
case IRQ_TYPE_LEVEL_HIGH:
mod ^= im;
break;
case IRQ_TYPE_NONE:
flow_type = IRQ_TYPE_LEVEL_LOW;
case IRQ_TYPE_LEVEL_LOW:
mod ^= im;
pol ^= im;
break;
case IRQ_TYPE_EDGE_RISING:
break;
default:
irq_gc_unlock(gc);
pr_err("%s: Cannot assign multiple trigger modes to IRQ %d.\n",
__func__, data->irq);
return -EBADR;
}
irqd_set_trigger_type(data, flow_type);
irq_setup_alt_chip(data, flow_type);
ab_irqctl_writereg(gc, AB_IRQCTL_SRC_MODE, mod);
ab_irqctl_writereg(gc, AB_IRQCTL_SRC_POLARITY, pol);
ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, im);
irq_gc_unlock(gc);
return IRQ_SET_MASK_OK;
}
static void tb10x_irq_cascade(struct irq_desc *desc)
{
struct irq_domain *domain = irq_desc_get_handler_data(desc);
unsigned int irq = irq_desc_get_irq(desc);
generic_handle_irq(irq_find_mapping(domain, irq));
}
static int __init of_tb10x_init_irq(struct device_node *ictl,
struct device_node *parent)
{
int i, ret, nrirqs = of_irq_count(ictl);
struct resource mem;
struct irq_chip_generic *gc;
struct irq_domain *domain;
void __iomem *reg_base;
if (of_address_to_resource(ictl, 0, &mem)) {
pr_err("%pOFn: No registers declared in DeviceTree.\n",
ictl);
return -EINVAL;
}
if (!request_mem_region(mem.start, resource_size(&mem),
ictl->full_name)) {
pr_err("%pOFn: Request mem region failed.\n", ictl);
return -EBUSY;
}
reg_base = ioremap(mem.start, resource_size(&mem));
if (!reg_base) {
ret = -EBUSY;
pr_err("%pOFn: ioremap failed.\n", ictl);
goto ioremap_fail;
}
domain = irq_domain_add_linear(ictl, AB_IRQCTL_MAXIRQ,
&irq_generic_chip_ops, NULL);
if (!domain) {
ret = -ENOMEM;
pr_err("%pOFn: Could not register interrupt domain.\n",
ictl);
goto irq_domain_add_fail;
}
ret = irq_alloc_domain_generic_chips(domain, AB_IRQCTL_MAXIRQ,
2, ictl->name, handle_level_irq,
IRQ_NOREQUEST, IRQ_NOPROBE,
IRQ_GC_INIT_MASK_CACHE);
if (ret) {
pr_err("%pOFn: Could not allocate generic interrupt chip.\n",
ictl);
goto gc_alloc_fail;
}
gc = domain->gc->gc[0];
gc->reg_base = reg_base;
gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK;
gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
gc->chip_types[0].chip.irq_set_type = tb10x_irq_set_type;
gc->chip_types[0].regs.mask = AB_IRQCTL_INT_ENABLE;
gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH;
gc->chip_types[1].chip.name = gc->chip_types[0].chip.name;
gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit;
gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit;
gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit;
gc->chip_types[1].chip.irq_set_type = tb10x_irq_set_type;
gc->chip_types[1].regs.ack = AB_IRQCTL_INT_STATUS;
gc->chip_types[1].regs.mask = AB_IRQCTL_INT_ENABLE;
gc->chip_types[1].handler = handle_edge_irq;
for (i = 0; i < nrirqs; i++) {
unsigned int irq = irq_of_parse_and_map(ictl, i);
irq_set_chained_handler_and_data(irq, tb10x_irq_cascade,
domain);
}
ab_irqctl_writereg(gc, AB_IRQCTL_INT_ENABLE, 0);
ab_irqctl_writereg(gc, AB_IRQCTL_INT_MODE, 0);
ab_irqctl_writereg(gc, AB_IRQCTL_INT_POLARITY, 0);
ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, ~0UL);
return 0;
gc_alloc_fail:
irq_domain_remove(domain);
irq_domain_add_fail:
iounmap(reg_base);
ioremap_fail:
release_mem_region(mem.start, resource_size(&mem));
return ret;
}
IRQCHIP_DECLARE(tb10x_intc, "abilis,tb10x-ictl", of_tb10x_init_irq);
