170 lines
4.0 KiB
C
170 lines
4.0 KiB
C
/*
|
|
* Multiplexed-IRQs driver for TS-4800's FPGA
|
|
*
|
|
* Copyright (c) 2015 - Savoir-faire Linux
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
|
|
#include <linux/interrupt.h>
|
|
#include <linux/io.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/irqchip.h>
|
|
#include <linux/irqchip/chained_irq.h>
|
|
#include <linux/irqdomain.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/seq_file.h>
|
|
|
|
#define IRQ_MASK 0x4
|
|
#define IRQ_STATUS 0x8
|
|
|
|
struct ts4800_irq_data {
|
|
void __iomem *base;
|
|
struct platform_device *pdev;
|
|
struct irq_domain *domain;
|
|
};
|
|
|
|
static void ts4800_irq_mask(struct irq_data *d)
|
|
{
|
|
struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
|
|
u16 reg = readw(data->base + IRQ_MASK);
|
|
u16 mask = 1 << d->hwirq;
|
|
|
|
writew(reg | mask, data->base + IRQ_MASK);
|
|
}
|
|
|
|
static void ts4800_irq_unmask(struct irq_data *d)
|
|
{
|
|
struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
|
|
u16 reg = readw(data->base + IRQ_MASK);
|
|
u16 mask = 1 << d->hwirq;
|
|
|
|
writew(reg & ~mask, data->base + IRQ_MASK);
|
|
}
|
|
|
|
static void ts4800_irq_print_chip(struct irq_data *d, struct seq_file *p)
|
|
{
|
|
struct ts4800_irq_data *data = irq_data_get_irq_chip_data(d);
|
|
|
|
seq_printf(p, "%s", dev_name(&data->pdev->dev));
|
|
}
|
|
|
|
static const struct irq_chip ts4800_chip = {
|
|
.irq_mask = ts4800_irq_mask,
|
|
.irq_unmask = ts4800_irq_unmask,
|
|
.irq_print_chip = ts4800_irq_print_chip,
|
|
};
|
|
|
|
static int ts4800_irqdomain_map(struct irq_domain *d, unsigned int irq,
|
|
irq_hw_number_t hwirq)
|
|
{
|
|
struct ts4800_irq_data *data = d->host_data;
|
|
|
|
irq_set_chip_and_handler(irq, &ts4800_chip, handle_simple_irq);
|
|
irq_set_chip_data(irq, data);
|
|
irq_set_noprobe(irq);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct irq_domain_ops ts4800_ic_ops = {
|
|
.map = ts4800_irqdomain_map,
|
|
.xlate = irq_domain_xlate_onecell,
|
|
};
|
|
|
|
static void ts4800_ic_chained_handle_irq(struct irq_desc *desc)
|
|
{
|
|
struct ts4800_irq_data *data = irq_desc_get_handler_data(desc);
|
|
struct irq_chip *chip = irq_desc_get_chip(desc);
|
|
u16 status = readw(data->base + IRQ_STATUS);
|
|
|
|
chained_irq_enter(chip, desc);
|
|
|
|
if (unlikely(status == 0)) {
|
|
handle_bad_irq(desc);
|
|
goto out;
|
|
}
|
|
|
|
do {
|
|
unsigned int bit = __ffs(status);
|
|
|
|
generic_handle_domain_irq(data->domain, bit);
|
|
status &= ~(1 << bit);
|
|
} while (status);
|
|
|
|
out:
|
|
chained_irq_exit(chip, desc);
|
|
}
|
|
|
|
static int ts4800_ic_probe(struct platform_device *pdev)
|
|
{
|
|
struct device_node *node = pdev->dev.of_node;
|
|
struct ts4800_irq_data *data;
|
|
int parent_irq;
|
|
|
|
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
|
|
if (!data)
|
|
return -ENOMEM;
|
|
|
|
data->pdev = pdev;
|
|
data->base = devm_platform_ioremap_resource(pdev, 0);
|
|
if (IS_ERR(data->base))
|
|
return PTR_ERR(data->base);
|
|
|
|
writew(0xFFFF, data->base + IRQ_MASK);
|
|
|
|
parent_irq = irq_of_parse_and_map(node, 0);
|
|
if (!parent_irq) {
|
|
dev_err(&pdev->dev, "failed to get parent IRQ\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
data->domain = irq_domain_add_linear(node, 8, &ts4800_ic_ops, data);
|
|
if (!data->domain) {
|
|
dev_err(&pdev->dev, "cannot add IRQ domain\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
irq_set_chained_handler_and_data(parent_irq,
|
|
ts4800_ic_chained_handle_irq, data);
|
|
|
|
platform_set_drvdata(pdev, data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ts4800_ic_remove(struct platform_device *pdev)
|
|
{
|
|
struct ts4800_irq_data *data = platform_get_drvdata(pdev);
|
|
|
|
irq_domain_remove(data->domain);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id ts4800_ic_of_match[] = {
|
|
{ .compatible = "technologic,ts4800-irqc", },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, ts4800_ic_of_match);
|
|
|
|
static struct platform_driver ts4800_ic_driver = {
|
|
.probe = ts4800_ic_probe,
|
|
.remove = ts4800_ic_remove,
|
|
.driver = {
|
|
.name = "ts4800-irqc",
|
|
.of_match_table = ts4800_ic_of_match,
|
|
},
|
|
};
|
|
module_platform_driver(ts4800_ic_driver);
|
|
|
|
MODULE_AUTHOR("Damien Riegel <damien.riegel@savoirfairelinux.com>");
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_ALIAS("platform:ts4800_irqc");
|