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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-04 05:10:15 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-04 05:10:15 +0300
commit999dcbe2414e15e19cdc1f91497d01f262c6e1cf (patch)
tree5ad7cfa7d337f4a38be8045130c7f1a213bbe925 /drivers/irqchip/irq-stm32-exti.c
parent5e1b834b27fb2c27cde33a0752425f11d10c0b2d (diff)
parent4cd13c21b207e80ddb1144c576500098f2d5f882 (diff)
downloadlinux-999dcbe2414e15e19cdc1f91497d01f262c6e1cf.tar.xz
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner: "The irq departement proudly presents: - A rework of the core infrastructure to optimally spread interrupt for multiqueue devices. The first version was a bit naive and failed to take thread siblings and other details into account. Developed in cooperation with Christoph and Keith. - Proper delegation of softirqs to ksoftirqd, so if ksoftirqd is active then no further softirq processsing on interrupt return happens. Otherwise we try to delegate and still run another batch of network packets in the irq return path, which then tries to delegate to ksoftirqd ..... - A proper machine parseable sysfs based alternative for /proc/interrupts. - ACPI support for the GICV3-ITS and ARM interrupt remapping - Two new irq chips from the ARM SoC zoo: STM32-EXTI and MVEBU-PIC - A new irq chip for the JCore (SuperH) - The usual pile of small fixlets in core and irqchip drivers" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits) softirq: Let ksoftirqd do its job genirq: Make function __irq_do_set_handler() static ARM/dts: Add EXTI controller node to stm32f429 ARM/STM32: Select external interrupts controller drivers/irqchip: Add STM32 external interrupts support Documentation/dt-bindings: Document STM32 EXTI controller bindings irqchip/mips-gic: Use for_each_set_bit to iterate over local IRQs pci/msi: Retrieve affinity for a vector genirq/affinity: Remove old irq spread infrastructure genirq/msi: Switch to new irq spreading infrastructure genirq/affinity: Provide smarter irq spreading infrastructure genirq/msi: Add cpumask allocation to alloc_msi_entry genirq: Expose interrupt information through sysfs irqchip/gicv3-its: Use MADT ITS subtable to do PCI/MSI domain initialization irqchip/gicv3-its: Factor out PCI-MSI part that might be reused for ACPI irqchip/gicv3-its: Probe ITS in the ACPI way irqchip/gicv3-its: Refactor ITS DT init code to prepare for ACPI irqchip/gicv3-its: Cleanup for ITS domain initialization PCI/MSI: Setup MSI domain on a per-device basis using IORT ACPI table ACPI: Add new IORT functions to support MSI domain handling ...
Diffstat (limited to 'drivers/irqchip/irq-stm32-exti.c')
-rw-r--r--drivers/irqchip/irq-stm32-exti.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-stm32-exti.c b/drivers/irqchip/irq-stm32-exti.c
new file mode 100644
index 000000000000..491568c95aa5
--- /dev/null
+++ b/drivers/irqchip/irq-stm32-exti.c
@@ -0,0 +1,201 @@
+/*
+ * 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 EXTI_IMR 0x0
+#define EXTI_EMR 0x4
+#define EXTI_RTSR 0x8
+#define EXTI_FTSR 0xc
+#define EXTI_SWIER 0x10
+#define EXTI_PR 0x14
+
+static void stm32_irq_handler(struct irq_desc *desc)
+{
+ struct irq_domain *domain = irq_desc_get_handler_data(desc);
+ struct irq_chip_generic *gc = domain->gc->gc[0];
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ unsigned long pending;
+ int n;
+
+ chained_irq_enter(chip, desc);
+
+ while ((pending = irq_reg_readl(gc, EXTI_PR))) {
+ for_each_set_bit(n, &pending, BITS_PER_LONG) {
+ generic_handle_irq(irq_find_mapping(domain, n));
+ irq_reg_writel(gc, BIT(n), EXTI_PR);
+ }
+ }
+
+ 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);
+ int pin = data->hwirq;
+ u32 rtsr, ftsr;
+
+ irq_gc_lock(gc);
+
+ rtsr = irq_reg_readl(gc, EXTI_RTSR);
+ ftsr = irq_reg_readl(gc, EXTI_FTSR);
+
+ 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, EXTI_RTSR);
+ irq_reg_writel(gc, ftsr, EXTI_FTSR);
+
+ 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);
+ int pin = data->hwirq;
+ u32 emr;
+
+ irq_gc_lock(gc);
+
+ emr = irq_reg_readl(gc, EXTI_EMR);
+ if (on)
+ emr |= BIT(pin);
+ else
+ emr &= ~BIT(pin);
+ irq_reg_writel(gc, emr, EXTI_EMR);
+
+ 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 = d->gc->gc[0];
+ struct irq_fwspec *fwspec = data;
+ irq_hw_number_t hwirq;
+
+ hwirq = fwspec->param[0];
+
+ 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(struct device_node *node,
+ struct device_node *parent)
+{
+ 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("%s: Unable to map registers\n", node->full_name);
+ return -ENOMEM;
+ }
+
+ /* Determine number of irqs supported */
+ writel_relaxed(~0UL, base + EXTI_RTSR);
+ nr_exti = fls(readl_relaxed(base + EXTI_RTSR));
+ writel_relaxed(0, base + EXTI_RTSR);
+
+ pr_info("%s: %d External IRQs detected\n", node->full_name, nr_exti);
+
+ domain = irq_domain_add_linear(node, nr_exti,
+ &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, nr_exti, 1, "exti",
+ handle_edge_irq, clr, 0, 0);
+ if (ret) {
+ pr_err("%s: Could not allocate generic interrupt chip.\n",
+ node->full_name);
+ goto out_free_domain;
+ }
+
+ gc = domain->gc->gc[0];
+ gc->reg_base = base;
+ gc->chip_types->type = IRQ_TYPE_EDGE_BOTH;
+ gc->chip_types->chip.name = gc->chip_types[0].chip.name;
+ 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 = EXTI_PR;
+ gc->chip_types->regs.mask = EXTI_IMR;
+ gc->chip_types->handler = handle_edge_irq;
+
+ 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;
+}
+
+IRQCHIP_DECLARE(stm32_exti, "st,stm32-exti", stm32_exti_init);