4.4-stable review patch. If anyone has any objections, please let me know.
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From: "H. Nikolaus Schaller" hns@goldelico.com
[ Upstream commit 934df23171e7c5b71d937104d4957891c39748ff ]
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 Signed-off-by: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/input/touchscreen/tsc2007.c | 8 ++++++++ 1 file changed, 8 insertions(+)
--- a/drivers/input/touchscreen/tsc2007.c +++ b/drivers/input/touchscreen/tsc2007.c @@ -455,6 +455,14 @@ static int tsc2007_probe(struct i2c_clie
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,