diff options
author | Brett T. Warden <brett.warden@gmail.com> | 2008-01-10 02:33:31 -0500 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@infradead.org> | 2008-01-25 16:04:51 -0500 |
commit | d685a483b8c92e3d0580b6c28e2ed531391c8c46 (patch) | |
tree | 65781891f244654f884cf18cdcd077b28f93bbac /drivers | |
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>
Diffstat (limited to 'drivers')
-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 58423525591f..032265383df2 100644 --- a/drivers/media/video/bw-qcam.c +++ b/drivers/media/video/bw-qcam.c | |||
@@ -82,11 +82,16 @@ OTHER DEALINGS IN THE SOFTWARE. | |||
82 | static unsigned int maxpoll=250; /* Maximum busy-loop count for qcam I/O */ | 82 | static unsigned int maxpoll=250; /* Maximum busy-loop count for qcam I/O */ |
83 | static unsigned int yieldlines=4; /* Yield after this many during capture */ | 83 | static unsigned int yieldlines=4; /* Yield after this many during capture */ |
84 | static int video_nr = -1; | 84 | static int video_nr = -1; |
85 | static unsigned int force_init; /* Whether to probe aggressively */ | ||
85 | 86 | ||
86 | module_param(maxpoll, int, 0); | 87 | module_param(maxpoll, int, 0); |
87 | module_param(yieldlines, int, 0); | 88 | module_param(yieldlines, int, 0); |
88 | module_param(video_nr, int, 0); | 89 | module_param(video_nr, int, 0); |
89 | 90 | ||
91 | /* Set force_init=1 to avoid detection by polling status register and | ||
92 | * immediately attempt to initialize qcam */ | ||
93 | module_param(force_init, int, 0); | ||
94 | |||
90 | static inline int read_lpstatus(struct qcam_device *q) | 95 | static inline int read_lpstatus(struct qcam_device *q) |
91 | { | 96 | { |
92 | return parport_read_status(q->pport); | 97 | return parport_read_status(q->pport); |
@@ -331,6 +336,9 @@ static int qc_detect(struct qcam_device *q) | |||
331 | int count = 0; | 336 | int count = 0; |
332 | int i; | 337 | int i; |
333 | 338 | ||
339 | if (force_init) | ||
340 | return 1; | ||
341 | |||
334 | lastreg = reg = read_lpstatus(q) & 0xf0; | 342 | lastreg = reg = read_lpstatus(q) & 0xf0; |
335 | 343 | ||
336 | for (i = 0; i < 500; i++) | 344 | for (i = 0; i < 500; i++) |
@@ -354,12 +362,12 @@ static int qc_detect(struct qcam_device *q) | |||
354 | 362 | ||
355 | /* Be (even more) liberal in what you accept... */ | 363 | /* Be (even more) liberal in what you accept... */ |
356 | 364 | ||
357 | /* if (count > 30 && count < 200) */ | ||
358 | if (count > 20 && count < 400) { | 365 | if (count > 20 && count < 400) { |
359 | return 1; /* found */ | 366 | return 1; /* found */ |
360 | } else { | 367 | } else { |
361 | printk(KERN_ERR "No Quickcam found on port %s\n", | 368 | printk(KERN_ERR "No Quickcam found on port %s\n", |
362 | q->pport->name); | 369 | q->pport->name); |
370 | printk(KERN_DEBUG "Quickcam detection counter: %u\n", count); | ||
363 | return 0; /* not found */ | 371 | return 0; /* not found */ |
364 | } | 372 | } |
365 | } | 373 | } |