From: Ian Abbott Date: Tue, 30 Oct 2018 14:44:16 +0000 (+0000) Subject: staging: comedi: cb_pcidda: Use insn->n in AO insn_write handler X-Git-Tag: Ubuntu-5.0.0-8.9~908^2~352 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=43818b03c518b7aed6bbe95ce2bcd4c5aaed2473;p=mirror_ubuntu-disco-kernel.git staging: comedi: cb_pcidda: Use insn->n in AO insn_write handler The `insn_write` handler for the AO subdevice (`cb_pcidda_ao_insn_write()`) currently ignores `insn->n` (the number of samples to write) and assumes a single sample is to be written. But `insn->n` could be 0, meaning no samples should be written, in which case `data[0]` is invalid. Follow the usual Comedi guidelines and change `cb_pcidda_ao_insn_write()` to write the specified number of samples. This fixes the assumption that `data[0]` is valid. Signed-off-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/comedi/drivers/cb_pcidda.c b/drivers/staging/comedi/drivers/cb_pcidda.c index 807a31e75883..1d09dd265ab7 100644 --- a/drivers/staging/comedi/drivers/cb_pcidda.c +++ b/drivers/staging/comedi/drivers/cb_pcidda.c @@ -291,6 +291,7 @@ static int cb_pcidda_ao_insn_write(struct comedi_device *dev, unsigned int channel = CR_CHAN(insn->chanspec); unsigned int range = CR_RANGE(insn->chanspec); unsigned int ctrl; + unsigned int i; if (range != devpriv->ao_range[channel]) cb_pcidda_calibrate(dev, channel, range); @@ -317,7 +318,8 @@ static int cb_pcidda_ao_insn_write(struct comedi_device *dev, outw(ctrl, devpriv->daqio + CB_DDA_DA_CTRL_REG); - outw(data[0], devpriv->daqio + CB_DDA_DA_DATA_REG(channel)); + for (i = 0; i < insn->n; i++) + outw(data[i], devpriv->daqio + CB_DDA_DA_DATA_REG(channel)); return insn->n; }