[media] v4l: Add AUTO option for the V4L2_CID_POWER_LINE_FREQUENCY co…

…ntrol V4L2_CID_POWER_LINE_FREQUENCY control allows applications to instruct a driver what is the power line frequency so an appropriate filter can be used by the device to cancel flicker by compensating the light intensity ripple. Currently in the menu we have entries for 50 Hz and 60 Hz and for entirely disabling the anti-flicker filter. However some devices are capable of automatically detecting the frequency, so add V4L2_CID_POWER_LINE_FREQUENCY_AUTO entry for them. Signed-off-by: Sylwester Nawrocki <[email protected]> Signed-off-by: Kyungmin Park <[email protected]> Acked-by: Laurent Pinchart <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]>
zuai · Nov 3, 2011 · d26a663 · d26a663
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commit d26a663
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Showing 3 changed files with 5 additions and 2 deletions.
diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml
@@ -232,8 +232,9 @@ control is deprecated. New drivers and applications should use the
 	    <entry>Enables a power line frequency filter to avoid
 flicker. Possible values for <constant>enum v4l2_power_line_frequency</constant> are:
 <constant>V4L2_CID_POWER_LINE_FREQUENCY_DISABLED</constant> (0),
-<constant>V4L2_CID_POWER_LINE_FREQUENCY_50HZ</constant> (1) and
-<constant>V4L2_CID_POWER_LINE_FREQUENCY_60HZ</constant> (2).</entry>
+<constant>V4L2_CID_POWER_LINE_FREQUENCY_50HZ</constant> (1),
+<constant>V4L2_CID_POWER_LINE_FREQUENCY_60HZ</constant> (2) and
+<constant>V4L2_CID_POWER_LINE_FREQUENCY_AUTO</constant> (3).</entry>
 	  </row>
 	  <row>
 	    <entry><constant>V4L2_CID_HUE_AUTO</constant></entry>

diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c
@@ -210,6 +210,7 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
 		"Disabled",
 		"50 Hz",
 		"60 Hz",
+		"Auto",
 		NULL
 	};
 	static const char * const camera_exposure_auto[] = {

diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
@@ -1169,6 +1169,7 @@ enum v4l2_power_line_frequency {
 	V4L2_CID_POWER_LINE_FREQUENCY_DISABLED	= 0,
 	V4L2_CID_POWER_LINE_FREQUENCY_50HZ	= 1,
 	V4L2_CID_POWER_LINE_FREQUENCY_60HZ	= 2,
+	V4L2_CID_POWER_LINE_FREQUENCY_AUTO	= 3,
 };
 #define V4L2_CID_HUE_AUTO			(V4L2_CID_BASE+25)
 #define V4L2_CID_WHITE_BALANCE_TEMPERATURE	(V4L2_CID_BASE+26)