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path: root/drivers/iio/trigger/iio-trig-interrupt.c
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Diffstat (limited to 'drivers/iio/trigger/iio-trig-interrupt.c')
-rw-r--r--drivers/iio/trigger/iio-trig-interrupt.c121
1 files changed, 121 insertions, 0 deletions
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");