The analog input subdevice supports Comedi asynchronous commands that
use Comedi's 16-bit sample format. However, the calls to
`comedi_buf_write_samples()` are passing the address of a 32-bit integer
variable. On bigendian machines, this will copy 2 bytes from the wrong
end of the 32-bit value. Fix it by changing the type of the variables
holding the sample value to `unsigned short`. The type of the `val`
parameter of `pci1710_ai_read_sample()` is changed to `unsigned short *`
accordingly. The type of the `val` variable in `pci1710_ai_insn_read()`
is also changed to `unsigned short` since its address is passed to
`pci1710_ai_read_sample()`.
Fixes: a9c3a015c12f ("staging: comedi: adv_pci1710: use comedi_buf_write_samples()")
Cc: <stable@xxxxxxxxxxxxxxx> # 4.0+
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
---
drivers/staging/comedi/drivers/adv_pci1710.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c
index 692893c7e5c3..090607760be6 100644
--- a/drivers/staging/comedi/drivers/adv_pci1710.c
+++ b/drivers/staging/comedi/drivers/adv_pci1710.c
@@ -300,11 +300,11 @@ static int pci1710_ai_eoc(struct comedi_device *dev,
static int pci1710_ai_read_sample(struct comedi_device *dev,
struct comedi_subdevice *s,
unsigned int cur_chan,
- unsigned int *val)
+ unsigned short *val)
{
const struct boardtype *board = dev->board_ptr;
struct pci1710_private *devpriv = dev->private;
- unsigned int sample;
+ unsigned short sample;
unsigned int chan;
sample = inw(dev->iobase + PCI171X_AD_DATA_REG);
@@ -345,7 +345,7 @@ static int pci1710_ai_insn_read(struct comedi_device *dev,
pci1710_ai_setup_chanlist(dev, s, &insn->chanspec, 1, 1);
for (i = 0; i < insn->n; i++) {
- unsigned int val;
+ unsigned short val;
/* start conversion */
outw(0, dev->iobase + PCI171X_SOFTTRG_REG);
@@ -395,7 +395,7 @@ static void pci1710_handle_every_sample(struct comedi_device *dev,
{
struct comedi_cmd *cmd = &s->async->cmd;
unsigned int status;
- unsigned int val;
+ unsigned short val;
int ret;
status = inw(dev->iobase + PCI171X_STATUS_REG);
@@ -455,7 +455,7 @@ static void pci1710_handle_fifo(struct comedi_device *dev,
}
for (i = 0; i < devpriv->max_samples; i++) {
- unsigned int val;
+ unsigned short val;
int ret;
ret = pci1710_ai_read_sample(dev, s, s->async->cur_chan, &val);
--
2.30.0
