| Message ID | 1364986219-8588-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/staging/comedi/drivers/s626.c b/drivers/staging/comedi/drivers/s626.c index e68e474..9c6b758 100644 --- a/drivers/staging/comedi/drivers/s626.c +++ b/drivers/staging/comedi/drivers/s626.c @@ -1823,7 +1823,7 @@ 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; }
This is a note to let you know that I have just added a patch titled staging: comedi: s626: fix continuous acquisition to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 48467539d71e1dabca1ab26855dfbaf35f061284 Mon Sep 17 00:00:00 2001 From: Ian Abbott <abbotti@mev.co.uk> Date: Fri, 22 Mar 2013 15:16:29 +0000 Subject: [PATCH] staging: comedi: s626: fix continuous acquisition commit e4317ce877a31dbb9d96375391c1c4ad2210d637 upstream. 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. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/staging/comedi/drivers/s626.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 1.8.1.2