On 2014-04-15 18:37, H Hartley Sweeten wrote:
Step 5 of the (*do_cmdtest) validates that the chanlist, chan/range/aref/etc,
is compatible with the actual hardware. At this point in the (*do_cmdtest)
the chanlist is valid, due to checks in the core, so the sanity check is not
needed.
For aesthetics, factor the step 5 code into a helper functions. Tidy up the
factored out code.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/cb_pcidas64.c | 106 ++++++++++++++++-----------
1 file changed, 62 insertions(+), 44 deletions(-)
diff --git a/drivers/staging/comedi/drivers/cb_pcidas64.c b/drivers/staging/comedi/drivers/cb_pcidas64.c
index 032bafe..a0756c5 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas64.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas64.c
@@ -1995,14 +1995,49 @@ static void check_adc_timing(struct comedi_device *dev, struct comedi_cmd *cmd)
return;
}
+static int cb_pcidas64_ai_check_chanlist(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_cmd *cmd)
+{
+ const struct pcidas64_board *board = comedi_board(dev);
+ unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
+ unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
+ int i;
+
+ for (i = 1; i < cmd->chanlist_len; i++) {
+ unsigned int aref = CR_AREF(cmd->chanlist[i]);
+
+ if (aref != aref0) {
+ dev_err(dev->class_dev,
+ "chanlist must use the same analog reference\n");
+ return -EINVAL;
+ }
+ }
+
+ if (board->layout == LAYOUT_4020) {
+ for (i = 1; i < cmd->chanlist_len; i++) {
+ unsigned int chan = CR_CHAN(cmd->chanlist[i]);
+ if (chan != chan0 + i) {
+ dev_err(dev->class_dev,
+ "chanlist must use consecutive channels\n");
+ return -EINVAL;
+ }
+ }
+ if (cmd->chanlist_len == 3) {
+ dev_err(dev->class_dev,
+ "chanlist cannot be 3 channels long, use 1, 2, or 4 channels\n");
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
static int ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
struct comedi_cmd *cmd)
{
const struct pcidas64_board *thisboard = comedi_board(dev);
int err = 0;
unsigned int tmp_arg, tmp_arg2;
- int i;
- int aref;
unsigned int triggers;
/* Step 1 : check if triggers are trivially valid */
@@ -2097,36 +2132,9 @@ static int ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
if (err)
return 4;
- /* make sure user is doesn't change analog reference mid chanlist */
- if (cmd->chanlist) {
- aref = CR_AREF(cmd->chanlist[0]);
- for (i = 1; i < cmd->chanlist_len; i++) {
- if (aref != CR_AREF(cmd->chanlist[i])) {
- comedi_error(dev,
- "all elements in chanlist must use the same analog reference");
- err++;
- break;
- }
- }
- /* check 4020 chanlist */
- if (thisboard->layout == LAYOUT_4020) {
- unsigned int first_channel = CR_CHAN(cmd->chanlist[0]);
- for (i = 1; i < cmd->chanlist_len; i++) {
- if (CR_CHAN(cmd->chanlist[i]) !=
- first_channel + i) {
- comedi_error(dev,
- "chanlist must use consecutive channels");
- err++;
- break;
- }
- }
- if (cmd->chanlist_len == 3) {
- comedi_error(dev,
- "chanlist cannot be 3 channels long, use 1, 2, or 4 channels");
- err++;
- }
- }
- }
+ /* Step 5: check channel list */
+
+ err |= cb_pcidas64_ai_check_chanlist(dev, s, cmd);
if (err)
return 5;
As for the remarks in patch 02, it's possible for chanlist to be NULL or
for chanlist_len to be 0, so cb_pcidas64_ai_check_chanlist() should only
be called if chanlist is non-NULL and chanlist_len is non-0.
But if chanlist is forced to be NULL by __comedi_get_user_chanlist()
when chanlist_len is 0, it would be sufficient to check that chanlist is
non-NULL before calling cb_pcidas64_ai_check_chanlist().
The original code is buggy as well because it accesses cmd->chanlist[0]
without checking cmd->chanlist_len.
@@ -3246,13 +3254,31 @@ static int ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
return 0;
}
+static int cb_pcidas64_ao_check_chanlist(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_cmd *cmd)
+{
+ unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
+ int i;
+
+ for (i = 1; i < cmd->chanlist_len; i++) {
+ unsigned int chan = CR_CHAN(cmd->chanlist[i]);
+
+ if (chan != chan0 + i) {
+ dev_err(dev->class_dev,
+ "chanlist must use consecutive channels");
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
static int ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
struct comedi_cmd *cmd)
{
const struct pcidas64_board *thisboard = comedi_board(dev);
int err = 0;
unsigned int tmp_arg;
- int i;
/* Step 1 : check if triggers are trivially valid */
@@ -3313,17 +3339,9 @@ static int ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
if (err)
return 4;
- if (cmd->chanlist) {
- unsigned int first_channel = CR_CHAN(cmd->chanlist[0]);
- for (i = 1; i < cmd->chanlist_len; i++) {
- if (CR_CHAN(cmd->chanlist[i]) != first_channel + i) {
- comedi_error(dev,
- "chanlist must use consecutive channels");
- err++;
- break;
- }
- }
- }
+ /* Step 5: check channel list */
+
+ err |= cb_pcidas64_ao_check_chanlist(dev, s, cmd);
if (err)
return 5;
Ditto for calling cb_pcidas64_ao_check_chanlist().
--
-=( Ian Abbott @ MEV Ltd. E-mail: <abbotti@xxxxxxxxx> )=-
-=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=-
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