iio: gyro: itg3200: add suspend/resume support.

Unless we put the device to sleep when not it use, it wastes
6mA.

If the device is asleep on probe, the 'id' register
sometimes mis-reads - so reset first.  If the device responds
at all a command sent to the address, it is almost certainly
the correct device already.

Acked-by: Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
Acked-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This commit is contained in:
NeilBrown 2015-02-24 13:24:41 +11:00 committed by Jonathan Cameron
parent d1bd4867b0
commit 60d3e3bbd5

View file

@ -223,6 +223,10 @@ static int itg3200_initial_setup(struct iio_dev *indio_dev)
int ret; int ret;
u8 val; u8 val;
ret = itg3200_reset(indio_dev);
if (ret)
goto err_ret;
ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val); ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val);
if (ret) if (ret)
goto err_ret; goto err_ret;
@ -233,10 +237,6 @@ static int itg3200_initial_setup(struct iio_dev *indio_dev)
goto err_ret; goto err_ret;
} }
ret = itg3200_reset(indio_dev);
if (ret)
goto err_ret;
ret = itg3200_enable_full_scale(indio_dev); ret = itg3200_enable_full_scale(indio_dev);
err_ret: err_ret:
return ret; return ret;
@ -351,6 +351,26 @@ static int itg3200_remove(struct i2c_client *client)
return 0; return 0;
} }
static int __maybe_unused itg3200_suspend(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct itg3200 *st = iio_priv(indio_dev);
dev_dbg(&st->i2c->dev, "suspend device");
return itg3200_write_reg_8(indio_dev, ITG3200_REG_POWER_MANAGEMENT,
ITG3200_SLEEP);
}
static int __maybe_unused itg3200_resume(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
return itg3200_initial_setup(indio_dev);
}
static SIMPLE_DEV_PM_OPS(itg3200_pm_ops, itg3200_suspend, itg3200_resume);
static const struct i2c_device_id itg3200_id[] = { static const struct i2c_device_id itg3200_id[] = {
{ "itg3200", 0 }, { "itg3200", 0 },
{ } { }
@ -361,6 +381,7 @@ static struct i2c_driver itg3200_driver = {
.driver = { .driver = {
.owner = THIS_MODULE, .owner = THIS_MODULE,
.name = "itg3200", .name = "itg3200",
.pm = &itg3200_pm_ops,
}, },
.id_table = itg3200_id, .id_table = itg3200_id,
.probe = itg3200_probe, .probe = itg3200_probe,