[media] gspca/autogain_functions.h: Allow users to declare what they want

Allow users of gspca/autogain_functions.h to declare which of the autogain
algoritms they are going to use. This allows us to remove the hacks from
drivers which don't use coarse_grained_expo_autogain.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/gspca/autogain_functions.h

@@ -18,6 +18,7 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#ifdef WANT_REGULAR_AUTOGAIN
 /* auto gain and exposure algorithm based on the knee algorithm described here:
    http://ytse.tricolour.net/docs/LowLightOptimization.html
 
@@ -91,7 +92,9 @@ static inline int auto_gain_n_exposure(
 			gain, exposure);
 	return retval;
 }
+#endif
 
+#ifdef WANT_COARSE_EXPO_AUTOGAIN
 /* Autogain + exposure algorithm for cameras with a coarse exposure control
    (usually this means we can only control the clockdiv to change exposure)
    As changing the clockdiv so that the fps drops from 30 to 15 fps for
@@ -103,7 +106,7 @@ static inline int auto_gain_n_exposure(
    which leads to oscilating as one exposure step is huge.
 
    Note this assumes that the sd struct for the cam in question has
-   exp_too_high_cnt and exp_too_high_cnt int members for use by this function.
+   exp_too_low_cnt and exp_too_high_cnt int members for use by this function.
 
    Returns 0 if no changes were made, 1 if the gain and or exposure settings
    where changed. */
@@ -177,3 +180,4 @@ static inline int coarse_grained_expo_autogain(
 			gain, exposure);
 	return retval;
 }
+#endif

drivers/media/video/gspca/nw80x.c

@@ -2001,6 +2001,8 @@ static int sd_setautogain(struct gspca_dev *gspca_dev, __s32 val)
 	return gspca_dev->usb_err;
 }
 
+#define WANT_REGULAR_AUTOGAIN
+#define WANT_COARSE_EXPO_AUTOGAIN
 #include "autogain_functions.h"
 
 static void do_autogain(struct gspca_dev *gspca_dev)

drivers/media/video/gspca/pac7302.c

@@ -729,9 +729,7 @@ static void sd_stop0(struct gspca_dev *gspca_dev)
 	reg_w(gspca_dev, 0x78, 0x40);
 }
 
-/* !! coarse_grained_expo_autogain is not used !! */
-#define exp_too_low_cnt flags
-#define exp_too_high_cnt sof_read
+#define WANT_REGULAR_AUTOGAIN
 #include "autogain_functions.h"
 
 static void do_autogain(struct gspca_dev *gspca_dev)

drivers/media/video/gspca/sonixb.c

@@ -1000,6 +1000,8 @@ static void setfreq(struct gspca_dev *gspca_dev)
 	}
 }
 
+#define WANT_REGULAR_AUTOGAIN
+#define WANT_COARSE_EXPO_AUTOGAIN
 #include "autogain_functions.h"
 
 static void do_autogain(struct gspca_dev *gspca_dev)

drivers/media/video/gspca/sonixj.c

@@ -2800,10 +2800,7 @@ static void sd_stop0(struct gspca_dev *gspca_dev)
 	}
 }
 
-/* !! coarse_grained_expo_autogain is not used !! */
-#define exp_too_low_cnt bridge
-#define exp_too_high_cnt sensor
-
+#define WANT_REGULAR_AUTOGAIN
 #include "autogain_functions.h"
 
 static void do_autogain(struct gspca_dev *gspca_dev)

drivers/media/video/gspca/topro.c

@@ -4675,11 +4675,9 @@ static void sd_pkt_scan(struct gspca_dev *gspca_dev,
 /* -- do autogain -- */
 /* gain setting is done in setexposure() for tp6810 */
 static void setgain(struct gspca_dev *gspca_dev) {}
-/* !! coarse_grained_expo_autogain is not used !! */
-#define exp_too_low_cnt bridge
-#define exp_too_high_cnt sensor
-
+#define WANT_REGULAR_AUTOGAIN
 #include "autogain_functions.h"
+
 static void sd_dq_callback(struct gspca_dev *gspca_dev)
 {
 	struct sd *sd = (struct sd *) gspca_dev;