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path: root/drivers/irqchip/irq-vt8500.c
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Diffstat (limited to 'drivers/irqchip/irq-vt8500.c')
-rw-r--r--drivers/irqchip/irq-vt8500.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-vt8500.c b/drivers/irqchip/irq-vt8500.c
new file mode 100644
index 00000000000..d97059550a2
--- /dev/null
+++ b/drivers/irqchip/irq-vt8500.c
@@ -0,0 +1,259 @@
+/*
+ * arch/arm/mach-vt8500/irq.c
+ *
+ * Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*
+ * This file is copied and modified from the original irq.c provided by
+ * Alexey Charkov. Minor changes have been made for Device Tree Support.
+ */
+
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+#include <asm/irq.h>
+#include <asm/exception.h>
+#include <asm/mach/irq.h>
+
+#include "irqchip.h"
+
+#define VT8500_ICPC_IRQ 0x20
+#define VT8500_ICPC_FIQ 0x24
+#define VT8500_ICDC 0x40 /* Destination Control 64*u32 */
+#define VT8500_ICIS 0x80 /* Interrupt status, 16*u32 */
+
+/* ICPC */
+#define ICPC_MASK 0x3F
+#define ICPC_ROTATE BIT(6)
+
+/* IC_DCTR */
+#define ICDC_IRQ 0x00
+#define ICDC_FIQ 0x01
+#define ICDC_DSS0 0x02
+#define ICDC_DSS1 0x03
+#define ICDC_DSS2 0x04
+#define ICDC_DSS3 0x05
+#define ICDC_DSS4 0x06
+#define ICDC_DSS5 0x07
+
+#define VT8500_INT_DISABLE 0
+#define VT8500_INT_ENABLE BIT(3)
+
+#define VT8500_TRIGGER_HIGH 0
+#define VT8500_TRIGGER_RISING BIT(5)
+#define VT8500_TRIGGER_FALLING BIT(6)
+#define VT8500_EDGE ( VT8500_TRIGGER_RISING \
+ | VT8500_TRIGGER_FALLING)
+
+/* vt8500 has 1 intc, wm8505 and wm8650 have 2 */
+#define VT8500_INTC_MAX 2
+
+struct vt8500_irq_data {
+ void __iomem *base; /* IO Memory base address */
+ struct irq_domain *domain; /* Domain for this controller */
+};
+
+/* Global variable for accessing io-mem addresses */
+static struct vt8500_irq_data intc[VT8500_INTC_MAX];
+static u32 active_cnt = 0;
+
+static void vt8500_irq_mask(struct irq_data *d)
+{
+ struct vt8500_irq_data *priv = d->domain->host_data;
+ void __iomem *base = priv->base;
+ void __iomem *stat_reg = base + VT8500_ICIS + (d->hwirq < 32 ? 0 : 4);
+ u8 edge, dctr;
+ u32 status;
+
+ edge = readb(base + VT8500_ICDC + d->hwirq) & VT8500_EDGE;
+ if (edge) {
+ status = readl(stat_reg);
+
+ status |= (1 << (d->hwirq & 0x1f));
+ writel(status, stat_reg);
+ } else {
+ dctr = readb(base + VT8500_ICDC + d->hwirq);
+ dctr &= ~VT8500_INT_ENABLE;
+ writeb(dctr, base + VT8500_ICDC + d->hwirq);
+ }
+}
+
+static void vt8500_irq_unmask(struct irq_data *d)
+{
+ struct vt8500_irq_data *priv = d->domain->host_data;
+ void __iomem *base = priv->base;
+ u8 dctr;
+
+ dctr = readb(base + VT8500_ICDC + d->hwirq);
+ dctr |= VT8500_INT_ENABLE;
+ writeb(dctr, base + VT8500_ICDC + d->hwirq);
+}
+
+static int vt8500_irq_set_type(struct irq_data *d, unsigned int flow_type)
+{
+ struct vt8500_irq_data *priv = d->domain->host_data;
+ void __iomem *base = priv->base;
+ u8 dctr;
+
+ dctr = readb(base + VT8500_ICDC + d->hwirq);
+ dctr &= ~VT8500_EDGE;
+
+ switch (flow_type) {
+ case IRQF_TRIGGER_LOW:
+ return -EINVAL;
+ case IRQF_TRIGGER_HIGH:
+ dctr |= VT8500_TRIGGER_HIGH;
+ __irq_set_handler_locked(d->irq, handle_level_irq);
+ break;
+ case IRQF_TRIGGER_FALLING:
+ dctr |= VT8500_TRIGGER_FALLING;
+ __irq_set_handler_locked(d->irq, handle_edge_irq);
+ break;
+ case IRQF_TRIGGER_RISING:
+ dctr |= VT8500_TRIGGER_RISING;
+ __irq_set_handler_locked(d->irq, handle_edge_irq);
+ break;
+ }
+ writeb(dctr, base + VT8500_ICDC + d->hwirq);
+
+ return 0;
+}
+
+static struct irq_chip vt8500_irq_chip = {
+ .name = "vt8500",
+ .irq_ack = vt8500_irq_mask,
+ .irq_mask = vt8500_irq_mask,
+ .irq_unmask = vt8500_irq_unmask,
+ .irq_set_type = vt8500_irq_set_type,
+};
+
+static void __init vt8500_init_irq_hw(void __iomem *base)
+{
+ u32 i;
+
+ /* Enable rotating priority for IRQ */
+ writel(ICPC_ROTATE, base + VT8500_ICPC_IRQ);
+ writel(0x00, base + VT8500_ICPC_FIQ);
+
+ /* Disable all interrupts and route them to IRQ */
+ for (i = 0; i < 64; i++)
+ writeb(VT8500_INT_DISABLE | ICDC_IRQ, base + VT8500_ICDC + i);
+}
+
+static int vt8500_irq_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ irq_set_chip_and_handler(virq, &vt8500_irq_chip, handle_level_irq);
+ set_irq_flags(virq, IRQF_VALID);
+
+ return 0;
+}
+
+static struct irq_domain_ops vt8500_irq_domain_ops = {
+ .map = vt8500_irq_map,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+asmlinkage void __exception_irq_entry vt8500_handle_irq(struct pt_regs *regs)
+{
+ u32 stat, i;
+ int irqnr, virq;
+ void __iomem *base;
+
+ /* Loop through each active controller */
+ for (i=0; i<active_cnt; i++) {
+ base = intc[i].base;
+ irqnr = readl_relaxed(base) & 0x3F;
+ /*
+ Highest Priority register default = 63, so check that this
+ is a real interrupt by checking the status register
+ */
+ if (irqnr == 63) {
+ stat = readl_relaxed(base + VT8500_ICIS + 4);
+ if (!(stat & BIT(31)))
+ continue;
+ }
+
+ virq = irq_find_mapping(intc[i].domain, irqnr);
+ handle_IRQ(virq, regs);
+ }
+}
+
+int __init vt8500_irq_init(struct device_node *node, struct device_node *parent)
+{
+ int irq, i;
+ struct device_node *np = node;
+
+ if (active_cnt == VT8500_INTC_MAX) {
+ pr_err("%s: Interrupt controllers > VT8500_INTC_MAX\n",
+ __func__);
+ goto out;
+ }
+
+ intc[active_cnt].base = of_iomap(np, 0);
+ intc[active_cnt].domain = irq_domain_add_linear(node, 64,
+ &vt8500_irq_domain_ops, &intc[active_cnt]);
+
+ if (!intc[active_cnt].base) {
+ pr_err("%s: Unable to map IO memory\n", __func__);
+ goto out;
+ }
+
+ if (!intc[active_cnt].domain) {
+ pr_err("%s: Unable to add irq domain!\n", __func__);
+ goto out;
+ }
+
+ set_handle_irq(vt8500_handle_irq);
+
+ vt8500_init_irq_hw(intc[active_cnt].base);
+
+ pr_info("vt8500-irq: Added interrupt controller\n");
+
+ active_cnt++;
+
+ /* check if this is a slaved controller */
+ if (of_irq_count(np) != 0) {
+ /* check that we have the correct number of interrupts */
+ if (of_irq_count(np) != 8) {
+ pr_err("%s: Incorrect IRQ map for slaved controller\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < 8; i++) {
+ irq = irq_of_parse_and_map(np, i);
+ enable_irq(irq);
+ }
+
+ pr_info("vt8500-irq: Enabled slave->parent interrupts\n");
+ }
+out:
+ return 0;
+}
+
+IRQCHIP_DECLARE(vt8500_irq, "via,vt8500-intc", vt8500_irq_init);