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authorHans de Goede <hdegoede@redhat.com>2010-02-17 11:59:19 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2010-02-26 15:11:09 -0300
commit5fb2dde28122e74bbab9dae3cc04bcbc8c08b332 (patch)
treeaaea47e29bf8a3783d5112c5000b3d4974f27e67 /drivers/media/video/gspca/pac7302.c
parent0e4b91c30605ae030d4ff63c5160e54c1bc2682c (diff)
V4L/DVB: gspca_pac7302: much improved exposure control
My experience with fixing up the controls for the PAS sensors in sonixb, has lead me to re-investigate the exposure control for the pac7302. I've now found a regular exposure register in register bank 3 (which seems to be the sensor registers bank), and with this added a proper fine grained exposure control. This patch also updates the do_autogain function to work properly with this new finer grained control. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/video/gspca/pac7302.c')
-rw-r--r--drivers/media/video/gspca/pac7302.c105
1 files changed, 50 insertions, 55 deletions
diff --git a/drivers/media/video/gspca/pac7302.c b/drivers/media/video/gspca/pac7302.c
index 19f0cd892db..2a68220d1ad 100644
--- a/drivers/media/video/gspca/pac7302.c
+++ b/drivers/media/video/gspca/pac7302.c
@@ -24,33 +24,26 @@
*/
/* Some documentation about various registers as determined by trial and error.
- When the register addresses differ between the 7202 and the 7311 the 2
- different addresses are written as 7302addr/7311addr, when one of the 2
- addresses is a - sign that register description is not valid for the
- matching IC.
Register page 1:
Address Description
- -/0x08 Unknown compressor related, must always be 8 except when not
- in 640x480 resolution and page 4 reg 2 <= 3 then set it to 9 !
- -/0x1b Auto white balance related, bit 0 is AWB enable (inverted)
- bits 345 seem to toggle per color gains on/off (inverted)
0x78 Global control, bit 6 controls the LED (inverted)
- -/0x80 JPEG compression ratio ? Best not touched
- Register page 3/4:
+ Register page 3:
Address Description
- 0x02 Clock divider 2-63, fps =~ 60 / val. Must be a multiple of 3 on
+ 0x02 Clock divider 3-63, fps = 90 / val. Must be a multiple of 3 on
the 7302, so one of 3, 6, 9, ..., except when between 6 and 12?
- -/0x0f Master gain 1-245, low value = high gain
- 0x10/- Master gain 0-31
- -/0x10 Another gain 0-15, limited influence (1-2x gain I guess)
+ 0x03 Variable framerate ctrl reg2==3: 0 -> ~30 fps, 255 -> ~22fps
+ 0x04 Another var framerate ctrl reg2==3, reg3==0: 0 -> ~30 fps,
+ 63 -> ~27 fps, the 2 msb's must always be 1 !!
+ 0x05 Another var framerate ctrl reg2==3, reg3==0, reg4==0xc0:
+ 1 -> ~30 fps, 2 -> ~20 fps
+ 0x0e Exposure bits 0-7, 0-448, 0 = use full frame time
+ 0x0f Exposure bit 8, 0-448, 448 = no exposure at all
+ 0x10 Master gain 0-31
0x21 Bitfield: 0-1 unused, 2-3 vflip/hflip, 4-5 unknown, 6-7 unused
- -/0x27 Seems to toggle various gains on / off, Setting bit 7 seems to
- completely disable the analog amplification block. Set to 0x68
- for max gain, 0x14 for minimal gain.
The registers are accessed in the following functions:
@@ -89,8 +82,8 @@ struct sd {
unsigned char red_balance;
unsigned char blue_balance;
unsigned char gain;
- unsigned char exposure;
unsigned char autogain;
+ unsigned short exposure;
__u8 hflip;
__u8 vflip;
u8 flags;
@@ -128,7 +121,6 @@ static int sd_setexposure(struct gspca_dev *gspca_dev, __s32 val);
static int sd_getexposure(struct gspca_dev *gspca_dev, __s32 *val);
static const struct ctrl sd_ctrls[] = {
-/* This control is pac7302 only */
{
{
.id = V4L2_CID_BRIGHTNESS,
@@ -144,7 +136,6 @@ static const struct ctrl sd_ctrls[] = {
.set = sd_setbrightness,
.get = sd_getbrightness,
},
-/* This control is for both the 7302 and the 7311 */
{
{
.id = V4L2_CID_CONTRAST,
@@ -160,7 +151,6 @@ static const struct ctrl sd_ctrls[] = {
.set = sd_setcontrast,
.get = sd_getcontrast,
},
-/* This control is pac7302 only */
{
{
.id = V4L2_CID_SATURATION,
@@ -218,7 +208,6 @@ static const struct ctrl sd_ctrls[] = {
.set = sd_setbluebalance,
.get = sd_getbluebalance,
},
-/* All controls below are for both the 7302 and the 7311 */
{
{
.id = V4L2_CID_GAIN,
@@ -241,11 +230,10 @@ static const struct ctrl sd_ctrls[] = {
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Exposure",
.minimum = 0,
-#define EXPOSURE_MAX 255
- .maximum = EXPOSURE_MAX,
+ .maximum = 1023,
.step = 1,
-#define EXPOSURE_DEF 16 /* 32 ms / 30 fps */
-#define EXPOSURE_KNEE 50 /* 100 ms / 10 fps */
+#define EXPOSURE_DEF 66 /* 33 ms / 30 fps */
+#define EXPOSURE_KNEE 133 /* 66 ms / 15 fps */
.default_value = EXPOSURE_DEF,
},
.set = sd_setexposure,
@@ -381,7 +369,7 @@ static const __u8 start_7302[] = {
#define SKIP 0xaa
/* page 3 - the value SKIP says skip the index - see reg_w_page() */
static const __u8 page3_7302[] = {
- 0x90, 0x40, 0x03, 0x50, 0xc2, 0x01, 0x14, 0x16,
+ 0x90, 0x40, 0x03, 0x00, 0xc0, 0x01, 0x14, 0x16,
0x14, 0x12, 0x00, 0x00, 0x00, 0x02, 0x33, 0x00,
0x0f, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x47, 0x01, 0xb3, 0x01, 0x00,
@@ -653,23 +641,39 @@ static void setgain(struct gspca_dev *gspca_dev)
static void setexposure(struct gspca_dev *gspca_dev)
{
struct sd *sd = (struct sd *) gspca_dev;
- __u8 reg;
-
- /* register 2 of frame 3/4 contains the clock divider configuring the
- no fps according to the formula: 60 / reg. sd->exposure is the
- desired exposure time in ms. */
- reg = 120 * sd->exposure / 1000;
- if (reg < 2)
- reg = 2;
- else if (reg > 63)
- reg = 63;
-
- /* On the pac7302 reg2 MUST be a multiple of 3, so round it to
- the nearest multiple of 3, except when between 6 and 12? */
- if (reg < 6 || reg > 12)
- reg = ((reg + 1) / 3) * 3;
+ __u8 clockdiv;
+ __u16 exposure;
+
+ /* register 2 of frame 3 contains the clock divider configuring the
+ no fps according to the formula: 90 / reg. sd->exposure is the
+ desired exposure time in 0.5 ms. */
+ clockdiv = (90 * sd->exposure + 1999) / 2000;
+
+ /* Note clockdiv = 3 also works, but when running at 30 fps, depending
+ on the scene being recorded, the camera switches to another
+ quantization table for certain JPEG blocks, and we don't know how
+ to decompress these blocks. So we cap the framerate at 15 fps */
+ if (clockdiv < 6)
+ clockdiv = 6;
+ else if (clockdiv > 63)
+ clockdiv = 63;
+
+ /* reg2 MUST be a multiple of 3, except when between 6 and 12?
+ Always round up, otherwise we cannot get the desired frametime
+ using the partial frame time exposure control */
+ if (clockdiv < 6 || clockdiv > 12)
+ clockdiv = ((clockdiv + 2) / 3) * 3;
+
+ /* frame exposure time in ms = 1000 * clockdiv / 90 ->
+ exposure = (sd->exposure / 2) * 448 / (1000 * clockdiv / 90) */
+ exposure = (sd->exposure * 45 * 448) / (1000 * clockdiv);
+ /* 0 = use full frametime, 448 = no exposure, reverse it */
+ exposure = 448 - exposure;
+
reg_w(gspca_dev, 0xff, 0x03); /* page 3 */
- reg_w(gspca_dev, 0x02, reg);
+ reg_w(gspca_dev, 0x02, clockdiv);
+ reg_w(gspca_dev, 0x0e, exposure & 0xff);
+ reg_w(gspca_dev, 0x0f, exposure >> 8);
/* load registers to sensor (Bit 0, auto clear) */
reg_w(gspca_dev, 0x11, 0x01);
@@ -756,22 +760,13 @@ static void do_autogain(struct gspca_dev *gspca_dev)
{
struct sd *sd = (struct sd *) gspca_dev;
int avg_lum = atomic_read(&sd->avg_lum);
- int desired_lum, deadzone;
+ int desired_lum;
+ const int deadzone = 30;
if (avg_lum == -1)
return;
- desired_lum = 270 + sd->brightness * 4;
- /* Hack hack, with the 7202 the first exposure step is
- pretty large, so if we're about to make the first
- exposure increase make the deadzone large to avoid
- oscilating */
- if (desired_lum > avg_lum && sd->gain == GAIN_DEF &&
- sd->exposure > EXPOSURE_DEF &&
- sd->exposure < 42)
- deadzone = 90;
- else
- deadzone = 30;
+ desired_lum = 270 + sd->brightness;
if (sd->autogain_ignore_frames > 0)
sd->autogain_ignore_frames--;