40.3.5 Power Saving
To save power consumption, the sensor can stop the image stream. In this case, proceed as
follows to enter the image subsystem in Low-power mode:
- Disable capture in ISC:
- ISC_CTRLDIS.DISABLE = 1 (to end capture at next vertical synchronization detection)
- Check ISC_CTRLSR.CAPTURE = 0
- Power down DPHY:
- CSI –> CSI2_RESETN = 0
- CSI –> CSI2_PHY_SHUTDOWNZ = 0
- CSI –> CSI2_DPHY_RSTZ = 0
- Reset CSI2DC software:
- CSI2DC –> CSI2DC_GCTLR = 1
The image subsystem is now in Low-power mode. Proceed as follows to restart the capture:
- Enable capture in ISC:
- With color profile update:
- Write all required configuration registers.
- ISC_CTRLEN = 0x3 (CAPTURE =1 and UPPRO =1)
- Without color profile update:
- ISC_CTRLDIS.CAPTURE = 1
- With color profile update:
- Release CSI2DC software reset:
- CSI2DC –> CSI2DC_GCTLR = 0
- Enable image pipe:
- CSI2DC –> CSI2DC_VPER = 1
- CSI2DC –> CSI2DC_DPER = 1
- CSI2DC –> CSI2DC_PUR = 0x3
- Bring DPHY out of power down:
- CSI –> CSI2_PHY_SHUTDOWNZ = 1
- CSI –> CSI2_DPHY_RSTZ = 1
- CSI –> CSI2_RESETN = 1
- Wait for LP-11 on the clock lane and activate data lanes by probing the CSI2_PHY_STOPSTATE register.
The image datapath can now start streaming frames.