On Wed, Dec 28, 2016 at 03:53:17PM +0100, H. Nikolaus Schaller wrote: > 1. check if chip is really present and don't succeed if it isn't. > 2. if it succeeds, power down the chip until accessed > > Signed-off-by: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> Applied, thank you. > --- > drivers/input/touchscreen/tsc2007.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c > index c1d9593..76b462b 100644 > --- a/drivers/input/touchscreen/tsc2007.c > +++ b/drivers/input/touchscreen/tsc2007.c > @@ -529,6 +529,14 @@ static int tsc2007_probe(struct i2c_client *client, > > tsc2007_stop(ts); > > + /* power down the chip (TSC2007_SETUP does not ACK on I2C) */ > + err = tsc2007_xfer(ts, PWRDOWN); > + if (err < 0) { > + dev_err(&client->dev, > + "Failed to setup chip: %d\n", err); > + return err; /* usually, chip does not respond */ > + } > + > err = input_register_device(input_dev); > if (err) { > dev_err(&client->dev, > -- > 2.7.3 > -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html