The first patch adds printing a warning in v4l2_get_link_freq() if V4L2_CID_LINK_FREQ isn't implemented (this is a mandatory control for CSI-2 transmitter drivers [1], but many sensor drivers don't have it currently). The second patch is the start of the work discussed in the "[RFC] Repurpose V4L2_CID_PIXEL_RATE for the sampling rate in the pixel array" thread [2]. I plan to send a few other similar patches for other CSI receiver drivers, and if the current patchset needs to wait for those before it can be merged, that's fine for me. The reason I decided to post the camss patch first is the patch [3] by Vladimir Lypak. The third patch in this series is the Vladimir's patch rebased onto the changes done by the second patch. By replacing getting the pixel clock with v4l2_get_link_freq() the second patch also fixes the integer overflow which Vladimir's patch addresses. So the third patch only needs to fix drivers/media/platform/qcom/camss/camss-vfe.c which the second patch doesn't touch. The resulting patchset is free from the "undefined reference to `__udivdi3'" issue [4] as the u64 value is only divided by a power of 2, which doesn't need do_div(). [1] https://linuxtv.org/downloads/v4l-dvb-apis-new/driver-api/csi2.html [2] https://www.spinics.net/lists/linux-media/msg183183.html [3] https://www.spinics.net/lists/linux-media/msg186875.html [4] https://www.spinics.net/lists/linux-media/msg186918.html Changes in v2: * Added [PATCH 1/3] v4l: common: v4l2_get_link_freq: add printing a warning * camss_get_link_freq() changed to take the actual number of lanes as the third arg vs the number of lanes multiplied by 2 in the first version * Fixed checkpatch warnings and bad indentation
