iio: gyro: Add itg3200
This patch adds support for the InvenSense itg3200.
The itg3200 is a three-axis gyro with 16-bit ADC and
I2C interface.
Signed-off-by: Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/gyro/itg3200_buffer.c b/drivers/iio/gyro/itg3200_buffer.c
new file mode 100644
index 0000000..f667d2c
--- /dev/null
+++ b/drivers/iio/gyro/itg3200_buffer.c
@@ -0,0 +1,156 @@
+/*
+ * 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;
+
+ if (indio_dev->scan_timestamp)
+ memcpy(buf + indio_dev->scan_bytes - sizeof(s64),
+ &pf->timestamp, sizeof(pf->timestamp));
+
+ iio_push_to_buffers(indio_dev, (u8 *)buf);
+ 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 = trig->private_data;
+ 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;
+ st->trig->private_data = indio_dev;
+ ret = iio_trigger_register(st->trig);
+ if (ret)
+ goto error_free_irq;
+
+ /* select default trigger */
+ indio_dev->trig = 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);
+}