You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
115 lines
3.0 KiB
115 lines
3.0 KiB
/*
|
|
* Aspeed 24XX/25XX I2C Interrupt Controller.
|
|
*
|
|
* Copyright (C) 2012-2017 ASPEED Technology Inc.
|
|
* Copyright 2017 IBM Corporation
|
|
* Copyright 2017 Google, Inc.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/irq.h>
|
|
#include <linux/irqchip.h>
|
|
#include <linux/irqchip/chained_irq.h>
|
|
#include <linux/irqdomain.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/io.h>
|
|
|
|
|
|
#define ASPEED_I2C_IC_NUM_BUS 14
|
|
|
|
struct aspeed_i2c_ic {
|
|
void __iomem *base;
|
|
int parent_irq;
|
|
struct irq_domain *irq_domain;
|
|
};
|
|
|
|
/*
|
|
* The aspeed chip provides a single hardware interrupt for all of the I2C
|
|
* busses, so we use a dummy interrupt chip to translate this single interrupt
|
|
* into multiple interrupts, each associated with a single I2C bus.
|
|
*/
|
|
static void aspeed_i2c_ic_irq_handler(struct irq_desc *desc)
|
|
{
|
|
struct aspeed_i2c_ic *i2c_ic = irq_desc_get_handler_data(desc);
|
|
struct irq_chip *chip = irq_desc_get_chip(desc);
|
|
unsigned long bit, status;
|
|
unsigned int bus_irq;
|
|
|
|
chained_irq_enter(chip, desc);
|
|
status = readl(i2c_ic->base);
|
|
for_each_set_bit(bit, &status, ASPEED_I2C_IC_NUM_BUS) {
|
|
bus_irq = irq_find_mapping(i2c_ic->irq_domain, bit);
|
|
generic_handle_irq(bus_irq);
|
|
}
|
|
chained_irq_exit(chip, desc);
|
|
}
|
|
|
|
/*
|
|
* Set simple handler and mark IRQ as valid. Nothing interesting to do here
|
|
* since we are using a dummy interrupt chip.
|
|
*/
|
|
static int aspeed_i2c_ic_map_irq_domain(struct irq_domain *domain,
|
|
unsigned int irq, irq_hw_number_t hwirq)
|
|
{
|
|
irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
|
|
irq_set_chip_data(irq, domain->host_data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct irq_domain_ops aspeed_i2c_ic_irq_domain_ops = {
|
|
.map = aspeed_i2c_ic_map_irq_domain,
|
|
};
|
|
|
|
static int __init aspeed_i2c_ic_of_init(struct device_node *node,
|
|
struct device_node *parent)
|
|
{
|
|
struct aspeed_i2c_ic *i2c_ic;
|
|
int ret = 0;
|
|
|
|
i2c_ic = kzalloc(sizeof(*i2c_ic), GFP_KERNEL);
|
|
if (!i2c_ic)
|
|
return -ENOMEM;
|
|
|
|
i2c_ic->base = of_iomap(node, 0);
|
|
if (IS_ERR(i2c_ic->base)) {
|
|
ret = PTR_ERR(i2c_ic->base);
|
|
goto err_free_ic;
|
|
}
|
|
|
|
i2c_ic->parent_irq = irq_of_parse_and_map(node, 0);
|
|
if (i2c_ic->parent_irq < 0) {
|
|
ret = i2c_ic->parent_irq;
|
|
goto err_iounmap;
|
|
}
|
|
|
|
i2c_ic->irq_domain = irq_domain_add_linear(node, ASPEED_I2C_IC_NUM_BUS,
|
|
&aspeed_i2c_ic_irq_domain_ops,
|
|
NULL);
|
|
if (!i2c_ic->irq_domain) {
|
|
ret = -ENOMEM;
|
|
goto err_iounmap;
|
|
}
|
|
|
|
i2c_ic->irq_domain->name = "aspeed-i2c-domain";
|
|
|
|
irq_set_chained_handler_and_data(i2c_ic->parent_irq,
|
|
aspeed_i2c_ic_irq_handler, i2c_ic);
|
|
|
|
pr_info("i2c controller registered, irq %d\n", i2c_ic->parent_irq);
|
|
|
|
return 0;
|
|
|
|
err_iounmap:
|
|
iounmap(i2c_ic->base);
|
|
err_free_ic:
|
|
kfree(i2c_ic);
|
|
return ret;
|
|
}
|
|
|
|
IRQCHIP_DECLARE(ast2400_i2c_ic, "aspeed,ast2400-i2c-ic", aspeed_i2c_ic_of_init);
|
|
IRQCHIP_DECLARE(ast2500_i2c_ic, "aspeed,ast2500-i2c-ic", aspeed_i2c_ic_of_init);
|
|
|