| Message ID | 20180517085405.10104-7-maxime.ripard@bootlin.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c index 77864a1a5eb0..e9bd0aa55409 100644 --- a/drivers/media/i2c/ov5640.c +++ b/drivers/media/i2c/ov5640.c @@ -1886,7 +1886,8 @@ static int ov5640_set_mode(struct ov5640_dev *sensor, * which is 8 bits per pixel. */ bpp = sensor->fmt.code == MEDIA_BUS_FMT_JPEG_1X8 ? 8 : 16; - rate = mode->pixel_clock * bpp; + rate = mode->vtot * mode->htot * bpp; + rate *= ov5640_framerates[sensor->current_fr]; if (sensor->ep.bus_type == V4L2_MBUS_CSI2) { rate = rate / sensor->ep.bus.mipi_csi2.num_data_lanes; ret = ov5640_set_mipi_pclk(sensor, rate);
The clock rate, while hardcoded until now, is actually a function of the resolution, framerate and bytes per pixel. Now that we have an algorithm to adjust our clock rate, we can select it dynamically when we change the mode. This changes a bit the clock rate being used, with the following effect: +------+------+------+------+-----+-----------------+----------------+-----------+ | Hact | Vact | Htot | Vtot | FPS | Hardcoded clock | Computed clock | Deviation | +------+------+------+------+-----+-----------------+----------------+-----------+ | 640 | 480 | 1896 | 1080 | 15 | 56000000 | 61430400 | 8.84 % | | 640 | 480 | 1896 | 1080 | 30 | 112000000 | 122860800 | 8.84 % | | 1024 | 768 | 1896 | 1080 | 15 | 56000000 | 61430400 | 8.84 % | | 1024 | 768 | 1896 | 1080 | 30 | 112000000 | 122860800 | 8.84 % | | 320 | 240 | 1896 | 984 | 15 | 56000000 | 55969920 | 0.05 % | | 320 | 240 | 1896 | 984 | 30 | 112000000 | 111939840 | 0.05 % | | 176 | 144 | 1896 | 984 | 15 | 56000000 | 55969920 | 0.05 % | | 176 | 144 | 1896 | 984 | 30 | 112000000 | 111939840 | 0.05 % | | 720 | 480 | 1896 | 984 | 15 | 56000000 | 55969920 | 0.05 % | | 720 | 480 | 1896 | 984 | 30 | 112000000 | 111939840 | 0.05 % | | 720 | 576 | 1896 | 984 | 15 | 56000000 | 55969920 | 0.05 % | | 720 | 576 | 1896 | 984 | 30 | 112000000 | 111939840 | 0.05 % | | 1280 | 720 | 1892 | 740 | 15 | 42000000 | 42002400 | 0.01 % | | 1280 | 720 | 1892 | 740 | 30 | 84000000 | 84004800 | 0.01 % | | 1920 | 1080 | 2500 | 1120 | 15 | 84000000 | 84000000 | 0.00 % | | 1920 | 1080 | 2500 | 1120 | 30 | 168000000 | 168000000 | 0.00 % | | 2592 | 1944 | 2844 | 1944 | 15 | 84000000 | 165862080 | 49.36 % | +------+------+------+------+-----+-----------------+----------------+-----------+ Only the 640x480, 1024x768 and 2592x1944 modes are significantly affected by the new formula. In this case, 640x480 and 1024x768 are actually fixed by this change. Indeed, the sensor was sending data at, for example, 27.33fps instead of 30fps. This is -9%, which is roughly what we're seeing in the array. Testing these modes with the new clock setup actually fix that error, and data are now sent at around 30fps. 2592x1944, on the other hand, is probably due to the fact that this mode can only be used using MIPI-CSI2, in a two lane mode, and never really tested with a DVP bus. Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com> --- drivers/media/i2c/ov5640.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)