/*
* Texas Instruments Keystone IRQ controller IP driver
*
* Copyright (C) 2014 Texas Instruments, Inc.
* Author: Sajesh Kumar Saran <sajesh@ti.com>
* Grygorii Strashko <grygorii.strashko@ti.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/irq.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/irqdomain.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include "irqchip.h"
/* The source ID bits start from 4 to 31 (total 28 bits)*/
#define BIT_OFS 4
#define KEYSTONE_N_IRQ (32 - BIT_OFS)
struct keystone_irq_device {
struct device *dev;
struct irq_chip chip;
u32 mask;
int irq;
struct irq_domain *irqd;
struct regmap *devctrl_regs;
u32 devctrl_offset;
};
static inline u32 keystone_irq_readl(struct keystone_irq_device *kirq)
{
int ret;
u32 val = 0;
ret = regmap_read(kirq->devctrl_regs, kirq->devctrl_offset, &val);
if (ret < 0)
dev_dbg(kirq->dev, "irq read failed ret(%d)\n", ret);
return val;
}
static inline void
keystone_irq_writel(struct keystone_irq_device *kirq, u32 value)
{
int ret;
ret = regmap_write(kirq->devctrl_regs, kirq->devctrl_offset, value);
if (ret < 0)
dev_dbg(kirq->dev, "irq write failed ret(%d)\n", ret);
}
static void keystone_irq_setmask(struct irq_data *d)
{
struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
kirq->mask |= BIT(d->hwirq);
dev_dbg(kirq->dev, "mask %lu [%x]\n", d->hwirq, kirq->mask);
}
static void keystone_irq_unmask(struct irq_data *d)
{
struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
kirq->mask &= ~BIT(d->hwirq);
dev_dbg(kirq->dev, "unmask %lu [%x]\n", d->hwirq, kirq->mask);
}
static void keystone_irq_ack(struct irq_data *d)
{
/* nothing to do here */
}
static void keystone_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct keystone_irq_device *kirq = irq_desc_get_handler_data(desc);
unsigned long pending;
int src, virq;
dev_dbg(kirq->dev, "start irq %d\n", irq);
chained_irq_enter(irq_desc_get_chip(desc), desc);
pending = keystone_irq_readl(kirq);
keystone_irq_writel(kirq, pending);
dev_dbg(kirq->dev, "pending 0x%lx, mask 0x%x\n", pending, kirq->mask);
pending = (pending >> BIT_OFS) & ~kirq->mask;
dev_dbg(kirq->dev, "pending after mask 0x%lx\n", pending);
for (src = 0; src < KEYSTONE_N_IRQ; src++) {
if (BIT(src) & pending) {
virq = irq_find_mapping(kirq->irqd, src);
dev_dbg(kirq->dev, "dispatch bit %d, virq %d\n",
src, virq);
if (!virq)
dev_warn(kirq->dev, "sporious irq detected hwirq %d, virq %d\n",
src, virq);
generic_handle_irq(virq);
}
}
chained_irq_exit(irq_desc_get_chip(desc), desc);
dev_dbg(kirq->dev, "end irq %d\n", irq);
}
static int keystone_irq_map(struct irq_domain *h, unsigned int virq,
irq_hw_number_t hw)
{
struct keystone_irq_device *kirq = h->host_data;
irq_set_chip_data(virq, kirq);
irq_set_chip_and_handler(virq, &kirq->chip, handle_level_irq);
set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
return 0;
}
static struct irq_domain_ops keystone_irq_ops = {
.map = keystone_irq_map,
.xlate = irq_domain_xlate_onecell,
};
static int keystone_irq_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct keystone_irq_device *kirq;
int ret;
if (np == NULL)
return -EINVAL;
kirq = devm_kzalloc(dev, sizeof(*kirq), GFP_KERNEL);
if (!kirq)
return -ENOMEM;
kirq->devctrl_regs =
syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
if (IS_ERR(kirq->devctrl_regs))
return PTR_ERR(kirq->devctrl_regs);
ret = of_property_read_u32_index(np, "ti,syscon-dev", 1,
&kirq->devctrl_offset);
if (ret) {
dev_err(dev, "couldn't read the devctrl_offset offset!\n");
return ret;
}
kirq->irq = platform_get_irq(pdev, 0);
if (kirq->irq < 0) {
dev_err(dev, "no irq resource %d\n", kirq->irq);
return kirq->irq;
}
kirq->dev = dev;
kirq->mask = ~0x0;
kirq->chip.name = "keystone-irq";
kirq->chip.irq_ack = keystone_irq_ack;
kirq->chip.irq_mask = keystone_irq_setmask;
kirq->chip.irq_unmask = keystone_irq_unmask;
kirq->irqd = irq_domain_add_linear(np, KEYSTONE_N_IRQ,
&keystone_irq_ops, kirq);
if (!kirq->irqd) {
dev_err(dev, "IRQ domain registration failed\n");
return -ENODEV;
}
platform_set_drvdata(pdev, kirq);
irq_set_chained_handler(kirq->irq, keystone_irq_handler);
irq_set_handler_data(kirq->irq, kirq);
/* clear all source bits */
keystone_irq_writel(kirq, ~0x0);
dev_info(dev, "irqchip registered, nr_irqs %u\n", KEYSTONE_N_IRQ);
return 0;
}
static int keystone_irq_remove(struct platform_device *pdev)
{
struct keystone_irq_device *kirq = platform_get_drvdata(pdev);
int hwirq;
for (hwirq = 0; hwirq < KEYSTONE_N_IRQ; hwirq++)
irq_dispose_mapping(irq_find_mapping(kirq->irqd, hwirq));
irq_domain_remove(kirq->irqd);
return 0;
}
static const struct of_device_id keystone_irq_dt_ids[] = {
{ .compatible = "ti,keystone-irq", },
{},
};
MODULE_DEVICE_TABLE(of, keystone_irq_dt_ids);
static struct platform_driver keystone_irq_device_driver = {
.probe = keystone_irq_probe,
.remove = keystone_irq_remove,
.driver = {
.name = "keystone_irq",
.of_match_table = of_match_ptr(keystone_irq_dt_ids),
}
};
module_platform_driver(keystone_irq_device_driver);
MODULE_AUTHOR("Texas Instruments");
MODULE_AUTHOR("Sajesh Kumar Saran");
MODULE_AUTHOR("Grygorii Strashko");
MODULE_DESCRIPTION("Keystone IRQ chip");
MODULE_LICENSE("GPL v2");
