From 7c00782b1d4b9073ae38891d636302b1267285af Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 26 Mar 2013 10:27:33 -0700 Subject: [PATCH] staging: comedi: ni_labpc: fix labpc_calib_insn_write() The comedi core expects the (*insn_write) operations to write insn->n values and return the number of values actually wrote. Make this function work like the core expects. As Ian Abbott pointed out for the eeprom writes, we really only need to write the last value to the caldac. The preceding data would be overwritten anyway. Signed-off-by: H Hartley Sweeten Cc: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/ni_labpc.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/staging/comedi/drivers/ni_labpc.c b/drivers/staging/comedi/drivers/ni_labpc.c index bae72eb73451..22f8d45ae6d5 100644 --- a/drivers/staging/comedi/drivers/ni_labpc.c +++ b/drivers/staging/comedi/drivers/ni_labpc.c @@ -1539,10 +1539,16 @@ static int labpc_calib_insn_write(struct comedi_device *dev, struct comedi_insn *insn, unsigned int *data) { - int channel = CR_CHAN(insn->chanspec); + unsigned int chan = CR_CHAN(insn->chanspec); - write_caldac(dev, channel, data[0]); - return 1; + /* + * Only write the last data value to the caldac. Preceding + * data would be overwritten anyway. + */ + if (insn->n > 0) + write_caldac(dev, chan, data[insn->n - 1]); + + return insn->n; } static int labpc_calib_insn_read(struct comedi_device *dev, -- 2.30.2