[PATCH v4 5/7] ARM: mediatek: Add sysirq interrupt polarity support

Yingjoe Chen
2014-10-23T15:55:22Z

Mediatek SoCs have interrupt polarity in sysirq which allows
to swap the polarity for given interrupts. Add this support
using hierarchy irq domain.

Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
---
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-mtk-sysirq.c | 168 +++++++++++++++++++++++++++++++++++++++
2 files changed, 169 insertions(+)
create mode 100644 drivers/irqchip/irq-mtk-sysirq.c

diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 73052ba..5a4dd73 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -34,3 +34,4 @@ obj-$(CONFIG_XTENSA) += irq-xtensa-pic.o
obj-$(CONFIG_XTENSA_MX) += irq-xtensa-mx.o
obj-$(CONFIG_IRQ_CROSSBAR) += irq-crossbar.o
obj-$(CONFIG_BRCMSTB_L2_IRQ) += irq-brcmstb-l2.o
+obj-$(CONFIG_ARCH_MEDIATEK) += irq-mtk-sysirq.o
diff --git a/drivers/irqchip/irq-mtk-sysirq.c b/drivers/irqchip/irq-mtk-sysirq.c
new file mode 100644
index 0000000..4403bcf
--- /dev/null
+++ b/drivers/irqchip/irq-mtk-sysirq.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright (c) 2014 MediaTek Inc.
+ * Author: Joe.C <yingjoe.chen@mediatek.com>
+ *
+ * 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.
+ *
+ * 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.
+ */
+
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "irqchip.h"
+
+#define MT6577_SYS_INTPOL_NUM (224)
+
+struct mtk_sysirq_chip_data {
+ spinlock_t lock;
+ void __iomem *intpol_base;
+};
+
+static int mtk_sysirq_set_type(struct irq_data *data, unsigned int type)
+{
+ irq_hw_number_t hwirq = data->hwirq;
+ struct mtk_sysirq_chip_data *chip_data = data->chip_data;
+ u32 offset, reg_index, value;
+ unsigned long flags;
+ int ret;
+
+ offset = hwirq & 0x1f;
+ reg_index = hwirq >> 5;
+
+ spin_lock_irqsave(&chip_data->lock, flags);
+ value = readl_relaxed(chip_data->intpol_base + reg_index * 4);
+ if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING) {
+ if (type == IRQ_TYPE_LEVEL_LOW)
+ type = IRQ_TYPE_LEVEL_HIGH;
+ else
+ type = IRQ_TYPE_EDGE_RISING;
+ value |= (1 << offset);
+ } else
+ value &= ~(1 << offset);
+ writel(value, chip_data->intpol_base + reg_index * 4);
+
+ data = data->parent_data;
+ ret = data->chip->irq_set_type(data, type);
+ spin_unlock_irqrestore(&chip_data->lock, flags);
+ return ret;
+}
+
+static struct irq_chip mtk_sysirq_chip = {
+ .name = "MT_SYSIRQ",
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_set_type = mtk_sysirq_set_type,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+};
+
+static int mtk_sysirq_domain_xlate(struct irq_domain *d,
+ struct device_node *controller,
+ const u32 *intspec, unsigned int intsize,
+ unsigned long *out_hwirq,
+ unsigned int *out_type)
+{
+ if (intsize < 3)
+ return -EINVAL;
+
+ /* sysirq doesn't support PPI */
+ if (intspec[0])
+ return -EINVAL;
+
+ *out_hwirq = intspec[1];
+ *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
+ return 0;
+}
+
+static int mtk_sysirq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ int i;
+ irq_hw_number_t hwirq;
+ struct of_phandle_args *irq_data = arg;
+
+ if (irq_data->args_count < 3)
+ return -EINVAL;
+
+ hwirq = irq_data->args[1];
+ for (i = 0; i < nr_irqs; i++)
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &mtk_sysirq_chip,
+ domain->host_data);
+
+ return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
+}
+
+static void mtk_sysirq_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ int i;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irq_set_handler(virq + i, NULL);
+ irq_domain_set_hwirq_and_chip(domain, virq + i, 0, NULL, NULL);
+ }
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+}
+
+static struct irq_domain_ops sysirq_domain_ops = {
+ .xlate = mtk_sysirq_domain_xlate,
+ .alloc = mtk_sysirq_domain_alloc,
+ .free = mtk_sysirq_domain_free,
+};
+
+static int __init mtk_sysirq_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_domain *domain, *domain_parent;
+ struct mtk_sysirq_chip_data *chip_data;
+ int ret = 0;
+
+ domain_parent = irq_find_host(parent);
+ if (!domain_parent) {
+ pr_err("mtk_sysirq: interrupt-parent not found\n");
+ return -EINVAL;
+ }
+
+ chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
+ if (!chip_data)
+ return -ENOMEM;
+
+ chip_data->intpol_base = of_io_request_and_map(node, 0, "intpol");
+ if (!chip_data->intpol_base) {
+ pr_err("mtk_sysirq: unable to map sysirq register\n");
+ ret = -ENOMEM;
+ goto out_free;
+ }
+
+ domain = irq_domain_add_linear(node, MT6577_SYS_INTPOL_NUM,
+ &sysirq_domain_ops, chip_data);
+ if (!domain) {
+ ret = -ENOMEM;
+ goto out_unmap;
+ }
+ domain->parent = domain_parent;
+ spin_lock_init(&chip_data->lock);
+
+ return 0;
+
+out_unmap:
+ iounmap(chip_data->intpol_base);
+out_free:
+ kfree(chip_data);
+ return ret;
+}
+IRQCHIP_DECLARE(mtk_sysirq, "mediatek,mt6577-sysirq", mtk_sysirq_of_init);
--
1.8.1.1.dirty