diff options
Diffstat (limited to 'drivers/iio/trigger/iio-trig-interrupt.c')
-rw-r--r-- | drivers/iio/trigger/iio-trig-interrupt.c | 121 |
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"); |