linux/drivers/irqchip/irq-stm32-exti.c

310 lines
7.6 KiB
C

/*
* Copyright (C) Maxime Coquelin 2015
* Author: Maxime Coquelin <mcoquelin.stm32@gmail.com>
* License terms: GNU General Public License (GPL), version 2
*/
#include <linux/bitops.h>
#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/of_address.h>
#include <linux/of_irq.h>
#define IRQS_PER_BANK 32
struct stm32_exti_bank {
u32 imr_ofst;
u32 emr_ofst;
u32 rtsr_ofst;
u32 ftsr_ofst;
u32 swier_ofst;
u32 pr_ofst;
};
static const struct stm32_exti_bank stm32f4xx_exti_b1 = {
.imr_ofst = 0x00,
.emr_ofst = 0x04,
.rtsr_ofst = 0x08,
.ftsr_ofst = 0x0C,
.swier_ofst = 0x10,
.pr_ofst = 0x14,
};
static const struct stm32_exti_bank *stm32f4xx_exti_banks[] = {
&stm32f4xx_exti_b1,
};
static const struct stm32_exti_bank stm32h7xx_exti_b1 = {
.imr_ofst = 0x80,
.emr_ofst = 0x84,
.rtsr_ofst = 0x00,
.ftsr_ofst = 0x04,
.swier_ofst = 0x08,
.pr_ofst = 0x88,
};
static const struct stm32_exti_bank stm32h7xx_exti_b2 = {
.imr_ofst = 0x90,
.emr_ofst = 0x94,
.rtsr_ofst = 0x20,
.ftsr_ofst = 0x24,
.swier_ofst = 0x28,
.pr_ofst = 0x98,
};
static const struct stm32_exti_bank stm32h7xx_exti_b3 = {
.imr_ofst = 0xA0,
.emr_ofst = 0xA4,
.rtsr_ofst = 0x40,
.ftsr_ofst = 0x44,
.swier_ofst = 0x48,
.pr_ofst = 0xA8,
};
static const struct stm32_exti_bank *stm32h7xx_exti_banks[] = {
&stm32h7xx_exti_b1,
&stm32h7xx_exti_b2,
&stm32h7xx_exti_b3,
};
static unsigned long stm32_exti_pending(struct irq_chip_generic *gc)
{
const struct stm32_exti_bank *stm32_bank = gc->private;
return irq_reg_readl(gc, stm32_bank->pr_ofst);
}
static void stm32_exti_irq_ack(struct irq_chip_generic *gc, u32 mask)
{
const struct stm32_exti_bank *stm32_bank = gc->private;
irq_reg_writel(gc, mask, stm32_bank->pr_ofst);
}
static void stm32_irq_handler(struct irq_desc *desc)
{
struct irq_domain *domain = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned int virq, nbanks = domain->gc->num_chips;
struct irq_chip_generic *gc;
const struct stm32_exti_bank *stm32_bank;
unsigned long pending;
int n, i, irq_base = 0;
chained_irq_enter(chip, desc);
for (i = 0; i < nbanks; i++, irq_base += IRQS_PER_BANK) {
gc = irq_get_domain_generic_chip(domain, irq_base);
stm32_bank = gc->private;
while ((pending = stm32_exti_pending(gc))) {
for_each_set_bit(n, &pending, IRQS_PER_BANK) {
virq = irq_find_mapping(domain, irq_base + n);
generic_handle_irq(virq);
stm32_exti_irq_ack(gc, BIT(n));
}
}
}
chained_irq_exit(chip, desc);
}
static int stm32_irq_set_type(struct irq_data *data, unsigned int type)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
const struct stm32_exti_bank *stm32_bank = gc->private;
int pin = data->hwirq % IRQS_PER_BANK;
u32 rtsr, ftsr;
irq_gc_lock(gc);
rtsr = irq_reg_readl(gc, stm32_bank->rtsr_ofst);
ftsr = irq_reg_readl(gc, stm32_bank->ftsr_ofst);
switch (type) {
case IRQ_TYPE_EDGE_RISING:
rtsr |= BIT(pin);
ftsr &= ~BIT(pin);
break;
case IRQ_TYPE_EDGE_FALLING:
rtsr &= ~BIT(pin);
ftsr |= BIT(pin);
break;
case IRQ_TYPE_EDGE_BOTH:
rtsr |= BIT(pin);
ftsr |= BIT(pin);
break;
default:
irq_gc_unlock(gc);
return -EINVAL;
}
irq_reg_writel(gc, rtsr, stm32_bank->rtsr_ofst);
irq_reg_writel(gc, ftsr, stm32_bank->ftsr_ofst);
irq_gc_unlock(gc);
return 0;
}
static int stm32_irq_set_wake(struct irq_data *data, unsigned int on)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
const struct stm32_exti_bank *stm32_bank = gc->private;
int pin = data->hwirq % IRQS_PER_BANK;
u32 imr;
irq_gc_lock(gc);
imr = irq_reg_readl(gc, stm32_bank->imr_ofst);
if (on)
imr |= BIT(pin);
else
imr &= ~BIT(pin);
irq_reg_writel(gc, imr, stm32_bank->imr_ofst);
irq_gc_unlock(gc);
return 0;
}
static int stm32_exti_alloc(struct irq_domain *d, unsigned int virq,
unsigned int nr_irqs, void *data)
{
struct irq_chip_generic *gc;
struct irq_fwspec *fwspec = data;
irq_hw_number_t hwirq;
hwirq = fwspec->param[0];
gc = irq_get_domain_generic_chip(d, hwirq);
irq_map_generic_chip(d, virq, hwirq);
irq_domain_set_info(d, virq, hwirq, &gc->chip_types->chip, gc,
handle_simple_irq, NULL, NULL);
return 0;
}
static void stm32_exti_free(struct irq_domain *d, unsigned int virq,
unsigned int nr_irqs)
{
struct irq_data *data = irq_domain_get_irq_data(d, virq);
irq_domain_reset_irq_data(data);
}
struct irq_domain_ops irq_exti_domain_ops = {
.map = irq_map_generic_chip,
.xlate = irq_domain_xlate_onetwocell,
.alloc = stm32_exti_alloc,
.free = stm32_exti_free,
};
static int
__init stm32_exti_init(const struct stm32_exti_bank **stm32_exti_banks,
int bank_nr, struct device_node *node)
{
unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
int nr_irqs, nr_exti, ret, i;
struct irq_chip_generic *gc;
struct irq_domain *domain;
void *base;
base = of_iomap(node, 0);
if (!base) {
pr_err("%pOF: Unable to map registers\n", node);
return -ENOMEM;
}
domain = irq_domain_add_linear(node, bank_nr * IRQS_PER_BANK,
&irq_exti_domain_ops, NULL);
if (!domain) {
pr_err("%s: Could not register interrupt domain.\n",
node->name);
ret = -ENOMEM;
goto out_unmap;
}
ret = irq_alloc_domain_generic_chips(domain, IRQS_PER_BANK, 1, "exti",
handle_edge_irq, clr, 0, 0);
if (ret) {
pr_err("%pOF: Could not allocate generic interrupt chip.\n",
node);
goto out_free_domain;
}
for (i = 0; i < bank_nr; i++) {
const struct stm32_exti_bank *stm32_bank = stm32_exti_banks[i];
u32 irqs_mask;
gc = irq_get_domain_generic_chip(domain, i * IRQS_PER_BANK);
gc->reg_base = base;
gc->chip_types->type = IRQ_TYPE_EDGE_BOTH;
gc->chip_types->chip.irq_ack = irq_gc_ack_set_bit;
gc->chip_types->chip.irq_mask = irq_gc_mask_clr_bit;
gc->chip_types->chip.irq_unmask = irq_gc_mask_set_bit;
gc->chip_types->chip.irq_set_type = stm32_irq_set_type;
gc->chip_types->chip.irq_set_wake = stm32_irq_set_wake;
gc->chip_types->regs.ack = stm32_bank->pr_ofst;
gc->chip_types->regs.mask = stm32_bank->imr_ofst;
gc->private = (void *)stm32_bank;
/* Determine number of irqs supported */
writel_relaxed(~0UL, base + stm32_bank->rtsr_ofst);
irqs_mask = readl_relaxed(base + stm32_bank->rtsr_ofst);
nr_exti = fls(readl_relaxed(base + stm32_bank->rtsr_ofst));
/*
* This IP has no reset, so after hot reboot we should
* clear registers to avoid residue
*/
writel_relaxed(0, base + stm32_bank->imr_ofst);
writel_relaxed(0, base + stm32_bank->emr_ofst);
writel_relaxed(0, base + stm32_bank->rtsr_ofst);
writel_relaxed(0, base + stm32_bank->ftsr_ofst);
writel_relaxed(~0UL, base + stm32_bank->pr_ofst);
pr_info("%s: bank%d, External IRQs available:%#x\n",
node->full_name, i, irqs_mask);
}
nr_irqs = of_irq_count(node);
for (i = 0; i < nr_irqs; i++) {
unsigned int irq = irq_of_parse_and_map(node, i);
irq_set_handler_data(irq, domain);
irq_set_chained_handler(irq, stm32_irq_handler);
}
return 0;
out_free_domain:
irq_domain_remove(domain);
out_unmap:
iounmap(base);
return ret;
}
static int __init stm32f4_exti_of_init(struct device_node *np,
struct device_node *parent)
{
return stm32_exti_init(stm32f4xx_exti_banks,
ARRAY_SIZE(stm32f4xx_exti_banks), np);
}
IRQCHIP_DECLARE(stm32f4_exti, "st,stm32-exti", stm32f4_exti_of_init);
static int __init stm32h7_exti_of_init(struct device_node *np,
struct device_node *parent)
{
return stm32_exti_init(stm32h7xx_exti_banks,
ARRAY_SIZE(stm32h7xx_exti_banks), np);
}
IRQCHIP_DECLARE(stm32h7_exti, "st,stm32h7-exti", stm32h7_exti_of_init);