Hi Javier, On Tue, Oct 9, 2012 at 8:16 AM, javier Martin <javier.martin@xxxxxxxxxxxxxxxxx> wrote: > This patch doesn't fix the BUG it claims to, since I have it working > properly in our Visstrim M10 platform without it. Look: Yes, it does fix a real bug. Without this patch the ov2640 cannot be probed, as it fails to read the product/vendor ID via I2C. I measure with the scope and do not get mclk at all without this patch. Again, camera probe does work fine on kernel 3.4. Does the mx27 feed the mclk to your camera? Which frequency do you get if you measure it with a scope. > > soc-camera-pdrv soc-camera-pdrv.0: Probing soc-camera-pdrv.0 > mx2-camera mx2-camera.0: Camera driver attached to camera 0 > ov7670 0-0021: chip found @ 0x42 (imx-i2c) > [..] > mx2-camera mx2-camera.0: Camera driver detached from camera 0 > mx2-camera mx2-camera.0: MX2 Camera (CSI) driver probed, clock > frequency: 66500000 This 66.5MHz is wrong. > > Furthermore, it's not correct, since there isn't such "per" clock for > the CSI in 3.5 [1], 3.6 [2], linux-next-20121008[3], or > next-20121009[4]. Well, you are looking to all git trees after the conversion to the common clock framework. Please look at 3.4 kernel instead and you will see that per4 is indeed used for csi. "DEFINE_CLOCK1(csi_clk, 0, NULL, 0, parent, &csi_clk1, &per4_clk);" In fact, the mx27 reference manual is the correct source for such information. Please check "Table 39-9. CSI Control Register 1 Field Descriptions (continued)": "Sensor Master Clock (MCLK) Divider. This field contains the divisor MCLK. The MCLK is derived from the PERCLK4." Can you let me know if this patch breaks things for you? Or what exactly you think is wrong with it? It seems that you are camera works by pure luck without this patch. Maybe you are turning per4 in the bootloader or you get the clock to your camera from somewhere else. Regards, Fabio Estevam -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
