Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / iio / gyro / itg3200_buffer.c

diff --git a/kernel/drivers/iio/gyro/itg3200_buffer.c b/kernel/drivers/iio/gyro/itg3200_buffer.c
new file mode 100644 (file)
index 0000000..eef50e9
--- /dev/null
+++ b/kernel/drivers/iio/gyro/itg3200_buffer.c
@@ -0,0 +1,153 @@
+/*
+ * itg3200_buffer.c -- support InvenSense ITG3200
+ *                     Digital 3-Axis Gyroscope driver
+ *
+ * Copyright (c) 2011 Christian Strobel <christian.strobel@iis.fraunhofer.de>
+ * Copyright (c) 2011 Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
+ * Copyright (c) 2012 Thorsten Nowak <thorsten.nowak@iis.fraunhofer.de>
+ *
+ * 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/slab.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/gyro/itg3200.h>
+
+
+static int itg3200_read_all_channels(struct i2c_client *i2c, __be16 *buf)
+{
+       u8 tx = 0x80 | ITG3200_REG_TEMP_OUT_H;
+       struct i2c_msg msg[2] = {
+               {
+                       .addr = i2c->addr,
+                       .flags = i2c->flags,
+                       .len = 1,
+                       .buf = &tx,
+               },
+               {
+                       .addr = i2c->addr,
+                       .flags = i2c->flags | I2C_M_RD,
+                       .len = ITG3200_SCAN_ELEMENTS * sizeof(s16),
+                       .buf = (char *)&buf,
+               },
+       };
+
+       return i2c_transfer(i2c->adapter, msg, 2);
+}
+
+static irqreturn_t itg3200_trigger_handler(int irq, void *p)
+{
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct itg3200 *st = iio_priv(indio_dev);
+       __be16 buf[ITG3200_SCAN_ELEMENTS + sizeof(s64)/sizeof(u16)];
+
+       int ret = itg3200_read_all_channels(st->i2c, buf);
+       if (ret < 0)
+               goto error_ret;
+
+       iio_push_to_buffers_with_timestamp(indio_dev, buf, pf->timestamp);
+
+       iio_trigger_notify_done(indio_dev->trig);
+
+error_ret:
+       return IRQ_HANDLED;
+}
+
+int itg3200_buffer_configure(struct iio_dev *indio_dev)
+{
+       return iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
+               itg3200_trigger_handler, NULL);
+}
+
+void itg3200_buffer_unconfigure(struct iio_dev *indio_dev)
+{
+       iio_triggered_buffer_cleanup(indio_dev);
+}
+
+
+static int itg3200_data_rdy_trigger_set_state(struct iio_trigger *trig,
+               bool state)
+{
+       struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+       int ret;
+       u8 msc;
+
+       ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_IRQ_CONFIG, &msc);
+       if (ret)
+               goto error_ret;
+
+       if (state)
+               msc |= ITG3200_IRQ_DATA_RDY_ENABLE;
+       else
+               msc &= ~ITG3200_IRQ_DATA_RDY_ENABLE;
+
+       ret = itg3200_write_reg_8(indio_dev, ITG3200_REG_IRQ_CONFIG, msc);
+       if (ret)
+               goto error_ret;
+
+error_ret:
+       return ret;
+
+}
+
+static const struct iio_trigger_ops itg3200_trigger_ops = {
+       .owner = THIS_MODULE,
+       .set_trigger_state = &itg3200_data_rdy_trigger_set_state,
+};
+
+int itg3200_probe_trigger(struct iio_dev *indio_dev)
+{
+       int ret;
+       struct itg3200 *st = iio_priv(indio_dev);
+
+       st->trig = iio_trigger_alloc("%s-dev%d", indio_dev->name,
+                                    indio_dev->id);
+       if (!st->trig)
+               return -ENOMEM;
+
+       ret = request_irq(st->i2c->irq,
+                         &iio_trigger_generic_data_rdy_poll,
+                         IRQF_TRIGGER_RISING,
+                         "itg3200_data_rdy",
+                         st->trig);
+       if (ret)
+               goto error_free_trig;
+
+
+       st->trig->dev.parent = &st->i2c->dev;
+       st->trig->ops = &itg3200_trigger_ops;
+       iio_trigger_set_drvdata(st->trig, indio_dev);
+       ret = iio_trigger_register(st->trig);
+       if (ret)
+               goto error_free_irq;
+
+       /* select default trigger */
+       indio_dev->trig = iio_trigger_get(st->trig);
+
+       return 0;
+
+error_free_irq:
+       free_irq(st->i2c->irq, st->trig);
+error_free_trig:
+       iio_trigger_free(st->trig);
+       return ret;
+}
+
+void itg3200_remove_trigger(struct iio_dev *indio_dev)
+{
+       struct itg3200 *st = iio_priv(indio_dev);
+
+       iio_trigger_unregister(st->trig);
+       free_irq(st->i2c->irq, st->trig);
+       iio_trigger_free(st->trig);
+}