diff options
| author | Brett T. Warden <brett.warden@gmail.com> | 2008-01-10 04:33:31 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@infradead.org> | 2008-01-25 19:04:51 -0200 |
| commit | d685a483b8c92e3d0580b6c28e2ed531391c8c46 (patch) | |
| tree | 65781891f244654f884cf18cdcd077b28f93bbac | |
| parent | a19602f26a24c32e491108b49790b106a6351f24 (diff) | |
V4L/DVB (7013): bw-qcam: add module parameter 'force_init' to skip polite auto-detection prior to direct initialization
Setting force_init=1 bypasses the friendly auto-detection by polling the
status register, and instead attempts to initialize the qcam directly. Not
friendly to other parallel devices, but much more reliable than the
auto-detection.
Signed-off-by: Brett T. Warden <brett.warden@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
| -rw-r--r-- | drivers/media/video/bw-qcam.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c index 58423525591..032265383df 100644 --- a/drivers/media/video/bw-qcam.c +++ b/drivers/media/video/bw-qcam.c @@ -82,11 +82,16 @@ OTHER DEALINGS IN THE SOFTWARE. static unsigned int maxpoll=250; /* Maximum busy-loop count for qcam I/O */ static unsigned int yieldlines=4; /* Yield after this many during capture */ static int video_nr = -1; +static unsigned int force_init; /* Whether to probe aggressively */ module_param(maxpoll, int, 0); module_param(yieldlines, int, 0); module_param(video_nr, int, 0); +/* Set force_init=1 to avoid detection by polling status register and + * immediately attempt to initialize qcam */ +module_param(force_init, int, 0); + static inline int read_lpstatus(struct qcam_device *q) { return parport_read_status(q->pport); @@ -331,6 +336,9 @@ static int qc_detect(struct qcam_device *q) int count = 0; int i; + if (force_init) + return 1; + lastreg = reg = read_lpstatus(q) & 0xf0; for (i = 0; i < 500; i++) @@ -354,12 +362,12 @@ static int qc_detect(struct qcam_device *q) /* Be (even more) liberal in what you accept... */ -/* if (count > 30 && count < 200) */ if (count > 20 && count < 400) { return 1; /* found */ } else { printk(KERN_ERR "No Quickcam found on port %s\n", q->pport->name); + printk(KERN_DEBUG "Quickcam detection counter: %u\n", count); return 0; /* not found */ } } |