3 files changed, 131 insertions, 0 deletions

diff --git a/drivers/iio/trigger/Kconfig b/drivers/iio/trigger/Kconfig
index a4e68db2f23f..360fd508b088 100644
--- a/drivers/iio/trigger/Kconfig
+++ b/drivers/iio/trigger/Kconfig
@@ -3,6 +3,15 @@
 #
 menu "Triggers - standalone"
 
+config IIO_INTERRUPT_TRIGGER
+        tristate "Generic interrupt trigger"
+        help
+          Provides support for using an interrupt of any type as an IIO
+          trigger.  This may be provided by a gpio driver for example.
+
+          To compile this driver as a module, choose M here: the
+          module will be called iio-trig-interrupt.
+
 config IIO_SYSFS_TRIGGER
         tristate "SYSFS trigger"
         depends on SYSFS
diff --git a/drivers/iio/trigger/Makefile b/drivers/iio/trigger/Makefile
index e0b21831072f..ce319a51b6af 100644
--- a/drivers/iio/trigger/Makefile
+++ b/drivers/iio/trigger/Makefile
@@ -2,4 +2,5 @@
 # Makefile for triggers not associated with iio-devices
 #
 
+obj-$(CONFIG_IIO_INTERRUPT_TRIGGER) += iio-trig-interrupt.o
 obj-$(CONFIG_IIO_SYSFS_TRIGGER) += iio-trig-sysfs.o
diff --git a/drivers/iio/trigger/iio-trig-interrupt.c b/drivers/iio/trigger/iio-trig-interrupt.c
new file mode 100644
index 000000000000..84bf397ec465
--- /dev/null
+++ b/drivers/iio/trigger/iio-trig-interrupt.c
@@ -0,0 +1,121 @@
+/*
+ * Industrial I/O - generic interrupt based trigger support
+ *
+ * Copyright (c) 2008-2013 Jonathan Cameron
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+
+
+struct iio_interrupt_trigger_info {
+        unsigned int irq;
+};
+
+static irqreturn_t iio_interrupt_trigger_poll(int irq, void *private)
+{
+        /* Timestamp not currently provided */
+        iio_trigger_poll(private, 0);
+        return IRQ_HANDLED;
+}
+
+static const struct iio_trigger_ops iio_interrupt_trigger_ops = {
+        .owner = THIS_MODULE,
+};
+
+static int iio_interrupt_trigger_probe(struct platform_device *pdev)
+{
+        struct iio_interrupt_trigger_info *trig_info;
+        struct iio_trigger *trig;
+        unsigned long irqflags;
+        struct resource *irq_res;
+        int irq, ret = 0;
+
+        irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+
+        if (irq_res == NULL)
+                return -ENODEV;
+
+        irqflags = (irq_res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
+
+        irq = irq_res->start;
+
+        trig = iio_trigger_alloc("irqtrig%d", irq_res->start);
+        if (!trig) {
+                ret = -ENOMEM;
+                goto error_ret;
+        }
+
+        trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
+        if (!trig_info) {
+                ret = -ENOMEM;
+                goto error_put_trigger;
+        }
+        iio_trigger_set_drvdata(trig, trig_info);
+        trig_info->irq = irq;
+        trig->ops = &iio_interrupt_trigger_ops;
+        ret = request_irq(irq, iio_interrupt_trigger_poll,
+                          irqflags, trig->name, trig);
+        if (ret) {
+                dev_err(&pdev->dev,
+                        "request IRQ-%d failed", irq);
+                goto error_free_trig_info;
+        }
+
+        ret = iio_trigger_register(trig);
+        if (ret)
+                goto error_release_irq;
+        platform_set_drvdata(pdev, trig);
+
+        return 0;
+
+/* First clean up the partly allocated trigger */
+error_release_irq:
+        free_irq(irq, trig);
+error_free_trig_info:
+        kfree(trig_info);
+error_put_trigger:
+        iio_trigger_put(trig);
+error_ret:
+        return ret;
+}
+
+static int iio_interrupt_trigger_remove(struct platform_device *pdev)
+{
+        struct iio_trigger *trig;
+        struct iio_interrupt_trigger_info *trig_info;
+
+        trig = platform_get_drvdata(pdev);
+        trig_info = iio_trigger_get_drvdata(trig);
+        iio_trigger_unregister(trig);
+        free_irq(trig_info->irq, trig);
+        kfree(trig_info);
+        iio_trigger_put(trig);
+
+        return 0;
+}
+
+static struct platform_driver iio_interrupt_trigger_driver = {
+        .probe = iio_interrupt_trigger_probe,
+        .remove = iio_interrupt_trigger_remove,
+        .driver = {
+                .name = "iio_interrupt_trigger",
+                .owner = THIS_MODULE,
+        },
+};
+
+module_platform_driver(iio_interrupt_trigger_driver);
+
+MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
+MODULE_DESCRIPTION("Interrupt trigger for the iio subsystem");
+MODULE_LICENSE("GPL v2");