This is a note to let you know that I've just added the patch titled staging: comedi: s626: fix continuous acquisition to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From e4317ce877a31dbb9d96375391c1c4ad2210d637 Mon Sep 17 00:00:00 2001 From: Ian Abbott <abbotti@xxxxxxxxx> Date: Fri, 22 Mar 2013 15:16:29 +0000 Subject: staging: comedi: s626: fix continuous acquisition For the s626 driver, there is a bug in the handling of asynchronous commands on the AI subdevice when the stop source is `TRIG_NONE`. The command should run continuously until cancelled, but the interrupt handler stops the command running after the first scan. The command set-up function `s626_ai_cmd()` contains this code: switch (cmd->stop_src) { case TRIG_COUNT: /* data arrives as one packet */ devpriv->ai_sample_count = cmd->stop_arg; devpriv->ai_continous = 0; break; case TRIG_NONE: /* continous acquisition */ devpriv->ai_continous = 1; devpriv->ai_sample_count = 0; break; } The interrupt handler `s626_irq_handler()` contains this code: if (!(devpriv->ai_continous)) devpriv->ai_sample_count--; if (devpriv->ai_sample_count <= 0) { devpriv->ai_cmd_running = 0; /* ... */ } So `devpriv->ai_sample_count` is only decremented for the `TRIG_COUNT` case, but `devpriv->ai_cmd_running` is set to 0 (and the command stopped) regardless. Fix this in `s626_ai_cmd()` by setting `devpriv->ai_sample_count = 1` for the `TRIG_NONE` case. The interrupt handler will not decrement it so it will remain greater than 0 and the check for stopping the acquisition will fail. Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/comedi/drivers/s626.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/s626.c b/drivers/staging/comedi/drivers/s626.c index 81a1fe6..71a73ec 100644 --- a/drivers/staging/comedi/drivers/s626.c +++ b/drivers/staging/comedi/drivers/s626.c @@ -1483,7 +1483,7 @@ static int s626_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s) case TRIG_NONE: /* continous acquisition */ devpriv->ai_continous = 1; - devpriv->ai_sample_count = 0; + devpriv->ai_sample_count = 1; break; } -- 1.8.1.rc1.5.g7e0651a -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html