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@goldelico.com --- 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 e9d5086..5e3c4bf 100644 --- a/drivers/input/touchscreen/tsc2007.c +++ b/drivers/input/touchscreen/tsc2007.c @@ -538,6 +538,14 @@ 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,